{"paper_id":"4a6a45cd-3705-4e3c-b402-c5333e2579b9","body_text":"1 \n \nProvisioning polyethylene glycol (PEG) to large herbivores in nutrient poor savannas can break food \nlimitation \nBRADLEY SCHRODER, 1 Wildlife Ecology and Conservation Group, Wageningen University, \nDroevendaalsesteeg 3a, 6708 PB Wageningen, the Netherlands  \nFRANK VAN LANGEVELDE,  Wildlife Ecology and Conservation Group, Wageningen University, \nDroevendaalsesteeg 3a, 6708 PB Wageningen, the Netherlands \nNICOLA-ANNE HAWKINS SCHRODER, No 13 Upper Waterkloof, 173 Regulus Street, Waterkloof, 0181, \nPretoria, South Africa \nHERBERT H. T. PRINS, Animal Sciences Group, Wageningen University, De Elst 1, 6708 WD Wageningen, \nthe Netherlands \nAbstract \nReproduction and survival of herbivores in nutrient poor savannas is low due to low nutrient and energy \navailability, partly caused by high levels of tannins. Polyethylene glycol (PEG) increases the availability of \nproteins for herbivores by binding tannins. The effect of PEG on the diet of free-roaming herbivores has not \nbeen tested. Our hypothesis was deploying lick blocks with the addition of PEG in a nutrient poor savanna, will \nresult in a broadening of the diet of free-roaming herbivores with higher percentages of browse species and \nhigher utilisation per browse species, with higher tannin levels. We further hypothesised that the mineral content \nin the faeces, once exposed to PEG would increase. We collected faecal samples of five herbivore species with \nvarious feeding methods (grazers, browsers or mixed feeders). The study used a Before-After-Control-Impact \n(BACI) design. The results show that the addition of PEG promotes a change in the browse dietary choices of \nfour of the five herbivore species, and are expressed as a broader choice of diet, coupled with higher numbers of \nbrowse species with low edibility and higher tannin levels. The addition of PEG had no noteworthy effect on the \nconcentration of minerals found in the faeces. \nKeywords: diet selection, food quality, game lick blocks, Polyethylene glycol (PEG), secondary compounds  \n \n \n \n \n \n \n \n1 Corresponding author: Dr Bradley Schroder - email: bradley.schroder@gmail.com \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n2 \n \nIntroduction \nNutrient poor savannas are dominated by broadleaved trees, having leaves with low nutritional value due to high \nlevels of secondary compounds, such as condensed tannin and other carbon-based secondary metabolites \n(Parker 2004; Mucina and Rutherford 2006; Hattas 2014). The secondary compounds are thought to be the \nplant’s evolutionary defence response to herbivore utilisation (Cooper and Owen-Smith 1985; Hattas 2014; \nScogings et al. 2014). Plants with high levels of secondary compounds can have relatively high nutrient \nconcentrations in their leaves (Tomlinson et al. 2016). It is well documented that condensed tannins occur in a \nwide range of plant species in nutrient poor savannas (Salawu et al. 1997) and that tannins bind with proteins \nand often suppress the food intake and digestion by mammalian herbivores (McLeod 1974; Cooper and Owen-\nSmith 1985; Smit 2013; Scogings et al. 2014; Mkhize et al. 2015). Browsers and mixed feeders’ foraging \npreferences are strongly shaped by secondary compounds (Scogings et al. 2014). \nPolyethylene glycol (PEG) (with commercial names such as Browse Plus or Movicol) is an inert and \nunabsorbed molecule, which binds with tannins to form a stable complex, preventing the binding between \ntannins and proteins (Badran and Jones 1965; Makkar et al. 1995; Majuva-Masafu and Linington 2006) \nincreasing the availability of proteins. PEG may increase the availability of macronutrients for herbivores and \ndecrease malaise (Provenza et al. 2000). To date, several studies have shown the effect of chemical defences and \nPEG on the diet of mammalian herbivores, such as goats ( Capra aegagrus hircus), sheep (Ovis aries) and cattle \n(Bos taurus africanus) (Salawu et al. 1997; Decandia et al. 2000; Moujahed et al. 2000; Landau et al. 2003; \nMkhize et al. 2015). Experiments have been undertaken on penned sheep and goats, with results showing that \ntannins not only act as digestibility reducers, but also as feeding deterrents that affect intake, feeding behaviour \nand diet choice of these herbivores (Foley and Hume 1987; Marsh et al. 2003; Jansen et al. 2007; Mkhize et al. \n2015; Mkhize et al. 2016). PEG has been shown to reduce these adverse effects of dietary tannins in these \ndomestic animal’s diets (Salawu et al. 1997; Moujahed et al. 2000; Mkhize et al. 2018). However, little is \nknown about the effect of PEG on free-roaming mammalian herbivores in nutrient poor savannas. Free-roaming \nherbivores encounter plant species that largely differ in concentrations of nutrients and plant secondary \ncompounds and they have the opportunity to select their diet to counteract the differences in forage quality and \nplant defences (Prins and Van Langevelde 2008). According to Prins and Van Langevelde (2008) and Provenza \net al. (2007), the fitness of herbivores increases when they have access to a variety of plant species with \ndifferent concentrations of nutrients and secondary compounds, than when constrained to a single food source. \nIn many game reserves in South Africa, especially on nutrient poor soils, nutrient lick blocks (standard game \nlick blocks) have been used, originally devised for domestic animals and now designed to supplement the diet of \nwild animals (Langman 1978; Makkar et al. 2007; SAFARI Feeds 2019; WES Feeds 2019) (see Supporting \nInformation A for the mineral composition of the standard game lick block in South Africa). Putman and Staines \n(2004) reviewed a number of studies that show experimentally that supplementary feeding free-roaming \nherbivores with game lick blocks resulted in an improvement of the wild animal’s health and reproductive life \ncycle. With the addition of PEG to game lick blocks, we expect that large herbivores are able to access \npreviously unusable proteins, indigestible fibres and other sources of energy, locked in plants which would \notherwise be unpalatable. This allows the herbivores to include additional plant species in their diet that have \nlevels of condensed tannins that are so high that they would not normally be consumed by herbivores without \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n3 \n \nPEG supplementation, especially during the dry winter months when good quality food is scarce. Our study \nanalyses the change in the diet of free-roaming mammalian herbivore species in response to game lick blocks \nwith and without the addition of PEG. Our hypothesis is that deploying game lick blocks with PEG compared to \nthe standard game lick blocks in a nutrient poor savanna will result in a broadening of the diet of herbivores \nwith a higher percentages of browse species and higher amounts of utilisation per browse species that have low \npalatability and generally have higher levels of condensed tannins. We further hypothesised that the mineral \ncontent within the faeces exposed to the game lick blocks with PEG would have an increase in mineral \nconcentrations. To test for differences in the quality of the diet after exposure to the game lick blocks, the \nminerals were compared in the faeces of mammalian herbivores exposed to standard game lick blocks versus \nthose exposed to the game lick blocks with the addition of PEG. An increase in the concentration of minerals in \nthe faeces would potentially show an increase in the quality of minerals obtained from the increase in diet range \nand quantity. \nMaterial and methods \nStudy area \nThe study was conducted in the Welgevonden Game Reserve (348 km²), situated on the Waterberg Plateau in \nSouth Africa (24°10'S; 27°45'E to 24°25'S; 27°56'E), over a period of three years (2016 – 2018). The area is \nclassified as warm and temperate, with summer rainfall, having distinct wet and dry seasons that stretch from \nOctober to March and April to September respectively, with a mean annual rainfall off 665 mm. The mean \nannual maximum temperature is 27.4°C (reaching 40°C) and the mean annual minimum temperature is 14.5°C \n(reaching -4°C). Welgevonden Game Reserve is situated in two biomes, the Savanna Biome and Grassland \nBiome, and falls mainly within the Waterberg Mountain Bushveld vegetation type (Mucina and Rutherford \n2006). The area is characterised primarily by the soil types dystrophic to mesotrophic yellow-brown apedal \ncoarse sands (Parker 2004), with ferruginous soils with a low pH. Accordingly, the vegetation type is dominated \nby nutritionally poor broadleaved savanna. Mucina and Rutherford (2006) classify this area as a nutrient poor \nsavanna ecosystem (locally termed ‘sour veld’, a.k.a. ‘dystrophic savanna’). The study area comprises \nmountainous terrain that is dissected by deep valleys, with occasional old agricultural lands. Flat plateaus \ncharacterise most of the hilltops, and the elevation varies from 1050 m to 1800 m above sea level. The previous \nland use included agriculture, cattle ranching and hunting, with the area now only being utilised for conservation \nand eco-tourism. Sixty-three species of free-roaming mammals have been identified in the study area, including \nvarious antelope species, mega-herbivores and predators.  \nMethods \nWe studied five mammalian herbivore species to establish the utilisation of PEG and the effect on herbivore \ndiets: one mixed feeder, viz., impala (Aepyceros melampus), two browsers, viz., greater kudu (Tragelaphus \nstrepsiceros) and the common eland (Taurotragus oryx), and two grazers, viz., Burchell’s zebra (Equus quagga \nburchellii) and the blue wildebeest (Connochaetes taurinus). To test the effect of the standard game lick block \nand the PEG game lick block on the diet of these herbivore species a Before-After-Control-Impact (BACI) \ndesign was used.  \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n4 \n \nThe topography of Welgevonden Game Reserve is determined by its underlying geology ( viz., an uplifted \nsandstone plateau crisscrossed by rifts) which creates valleys flanked by steep hill slopes. Due to the steep \ntopography the normal movement patterns of herbivore species is primarily along the valleys (Mr. J Swart 2017, \npersonal communication) and rarely between them. Six sites were identified within six valleys, which were \nroughly 4 – 5 kms apart, to prevent individual animals visiting more than one site during the study. A ‘transect’ \nof 12 game lick blocks were aligned at 25m intervals running centrally through each valley (Figure 1, shows the \nlayout design of the game lick blocks in the study area). The transect layout maximised the chance that the \nanimals would eat and defecate in the same area ensuring the faecal samples obtained for analysis were from \nanimals which had consumed either the standard or PEG game lick block, post deployment of the lick blocks. \nPrior to the game lick blocks being deployed faecal samples of the five-herbivore species were collected from \nthe six predetermined sites (‘Before Assessment’ analysis). Samples were collected from the area 25m prior to \nwhere the first lick block would be deployed and to 25m after where the last lick block would be deployed and \nat a diameter of 25m either side of the transect. Two types of game lick blocks (each with an individual mass of \n25kg) were then deployed in the study area at the six sites (three sites per game lick block type). The first type \nwas the standard game lick block (of which the nutrient supplements are given in Supporting Information A), \nthe second was the standard game lick blocks with the addition of 35g of PEG per 25kg block (WES Feeds \n2019, personal communication as per our request). The game lick blocks were placed along a transect within \neach site for consumption during the dry months of the year (May through October). The game lick blocks were \nreplaced every two to three weeks until the end of October. A second collection of faecal samples were collected \nin early November (‘After Assessment’ analysis). All the herbivore species could voluntarily choose to consume \nor not to consume the game lick blocks. As dictated by standard practise, the game lick blocks were not \nprovided during the wet season (November through May), as they can negatively affect herbivores. \nDuring this experiment, the health and welfare of the free-roaming animals was observed and checked regularly \nand at no stage during this experiment were any animals harmed. \n \n \n \n \n \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n5 \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \nFigure 1. Map of the Welgevonden Game Reserve showing the grazing lawn experimental sites and layout of \ntreatment plots. WGR = Welgevonden Game Reserve \n \nData Collection \nThe experiment was repeated over a three-year period (2016 to 2018). The faecal sample collection prior to the \ngame lick block application was undertaken in April of each year. The game lick blocks were placed in transects \nat the beginning of May and replaced every two to three weeks until the end of October, which is a period of six \nmonths each year. The faecal sample collection after the game lick block applications was done in early \nNovember of each year. A minimum of five individual faecal samples per animal species were collected (each \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n6 \n \nsample was no less than five pellets), if there were less than five samples per animal species to collect, that \nspecies faeces were not included in the site data analysis for that month. The sample was estimated to be no \nolder than five days based on water retention and colour. Over the three-year period 655 individual faecal \nsamples (different animal droppings from each of the five species) were collected from the five species. The \nfaecal samples collected per species were represented as follows, impala (145), greater kudu (119), common \neland (80), Burchell’s zebra (156) and blue wildebeest (155).  \nEach faeces sample was analysed for mineral concentrations and the presence of individual grass and woody \nplant species. The mineral concentrations of the faeces were analysed after the six-month period of game block \ndeployment/application to compare the mineral concentration between herbivores exposed to the standard verses \nPEG game lick blocks. The minerals analysed in the faeces have important uses for the five large free-roaming \nherbivores (Table 1) and were analysed either as a percentage in the case of (N, Ca, Mg, K, S and P) or as mg/kg \nas with (Na, Fe, Mn, Cu, Zn and B) using the Combustion method (DUMAS test) for N and the Inductively \ncoupled plasma optical emission spectroscopy (ICP-OES) test for the remaining minerals. \nTable 1. Important use of minerals and elements for free-roaming herbivores (Roosendaal 1992; McDowell & \nArthington 2005) which are included in the faeces mineral concentration analysis \nNutrient/Element/Mineral Use in free-roaming herbivores \nSodium (Na) Used by animals in extracellular fluids such as blood plasma  \nNitrogen (N) A major component of protein in animals and used for growth, reproduction \nand survival \nCalcium (Ca) Mineral found in greatest abundances in animals and used for structural \nsupport especially in the bones \nMagnesium (Mg) Important mineral assisting with nerve and muscle function, immune system \nfunction and bone health \nPotassium (K) Necessary for the function of all living cells  \nSulphur (S) Important for ruminants for growth and milk production  \nPhosphorus (P) Essential mineral for cell development and a key component to store energy  \nIron (Fe) Used to produce haemoglobin, which delivers oxygen to the blood and \ncarbon dioxide out of the body \nManganese (Mn) Important trace mineral for enzyme activation and stimulates growth  \nCopper (Cu) Essential trace element required for body, bone and white blood cell function  \nZinc (Zn) Used for cellular respiration, cellular use of oxygen and maintenance of cell \nmembranes \nBoron (B) Used for immune response, antioxidant, bone metabolism and enhancing \nanimal performance \n \nThe faecal mineral content analyses are useful as short-term indicators of diet selection and nutrient status of \nfree-roaming herbivores (Botha and Stock 2005; Codron et al. 2005). \nThe presence of individual grass and woody plant species were analysed using microhistological faecal analysis \nvia observation of plant cuticles or epidermal fragments found in the faeces. The cuticle and epidermis of plants \nhave specific structures and patterns so they can be individually identified using a microscope, to the plant \nspecies level (De Jong et al. 1995). This analysis allowed us to establish the individual species of browse and \ngraze that the animals had been utilising. 100 fragments per faeces sample were randomly selected and analysed \nand then used to describe the animal’s diet (Van Lieverloo et al. 2009). The number of individual fragments per \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n7 \n \nspecies within the faeces sample, could be used as a proxy for the amount of materials per plant species \nconsumed by the animal (De Jong et al. 1995). The Welgevonden Game Reserve plant species collection list \nwas used as the reference to authenticate the species identified within the faeces samples. Both the woody plant \nspecies and grass species identified in the faeces were ranked according to their estimated palatability \n(Supporting Information B and C). Palatability is difficult to define in terms of the biological processes involved \nin food selection. As commonly used the term implies acceptability but not necessarily desirability (Molyneux \nand Ralphs 1992). Tree species digestibility ratings were established through the use of the Field Guide to \nTREES of Southern Africa (Van Wyk and Van Wyk 1997) and through the independent advice of experts in the \nfield (Supporting Information B). Grazing values of the grasses were obtained from the Guide to Grasses of \nsouthern Africa (Van Oudtshoorn 2002). The faeces were not analysed for herbs (forbs). \nIn Supporting Information D and E, the individual species of browse and grass found in the faeces of the five-\nanimal species during the study period are listed, together with the palatability of plant species and grazing \nratings of grass species, coupled with the diet change per herbivore species.   \nStatistical Analysis \nThe change in diet was analysed when comparing before versus after deployment of the standard game lick \nblocks and the PEG augmented game lick blocks. Therefore, comparing plant species composition in the diets \nusing a Principal Component Analysis (PCA). The PCA allowed for the correlation in the change in diet with \nthe quality of the plant species (palatability of the tree species and grazing values for the grass species). The \nhypothesis was tested using linear mixed models (LMMs) with mineral concentrations of the faeces and the \npercentage of browse species in the diet as response variables, and animal species, before versus after and PEG-\naugmented game lick blocks versus standard game lick blocks as fixed factors and year and site as random \nfactors. The differences between the animal species were analysed using Šidák multiple comparisons tests. If the \nresiduals of the Linear mixed models were not normally distributed transformation of the response variable was \nperformed. Analysis for the PCA were performed in Canoco 5.0 (Šmilauer and Lepš 2014) and all other analysis \nwas performed using SPSS v. 23 (IBM SPSS Inc., Chicago, USA).  \nResults \nPercentage browse in diet \nThe addition of PEG to the standard game lick blocks promotes a change in the dietary choices of four of the \nfive herbivore species namely the common eland, greater kudu, Burchell’s zebra and impala. These changes can \nbe expressed as a broader diet choice, either as a higher percentage of browse species or a higher number of \nindividual species utilised with higher concentrations of secondary compounds and low to average palatability \nin their diet. We found that due to the consumption of the PEG game lick blocks, two of the five herbivore \nspecies, impala and Burchell’s zebra, had statistically significant changes in the percentage of browse utilised in \ntheir diet. (Figure 2, Table 2). There were smaller changes in increased browse utilisation in the common eland \nand greater kudu. There was a decrease in browse utilisation by blue wildebeest after the consumption of the \nPEG game lick block (Table 3). \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n8 \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \nFigure 2. Percentage of total browse species consumption, over a 3-year period, collected in the Welgevonden \nGame Reserve, South Africa, for each herbivore species ( viz. impala (Aepyceros melampus), greater kudu \n(Tragelaphus strepsiceros), common eland (Taurotragus oryx), Burchell’s zebra (Equus quagga burchellii) and \nthe blue wildebeest (Connochaetes taurinus) per game lick block type. Before and After refers to the percentage \nof total browse species in the diet taken before or after the utilisation of either the standard game lick blocks \n(STD) or the game lick block with the addition of Polyethylene glycol (PEG). Error bars represent the standard \nerror of the mean. The stars indicate the statistically significant differences between the STD and PEG game lick \nblocks per species and per treatment based on Šidák multiple comparisons tests using a linear mixed model (see \nTable 2 for the statistics) \n \n \n \n \n \n \n \n \n \n \n \n* * \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n9 \n \nTable 2. Results of the linear mixed model for differences in percentage of browse species in the faeces before \nand after applying the Standard (STD) and Polyethylene glycol (PEG) game lick blocks (“block type”) for the \nfive herbivore species (viz. impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros), common \neland (Taurotragus oryx), Burchell’s zebra (Equus quagga burchellii) and the blue wildebeest (Connochaetes \ntaurinus). Year and site were the random factors, estimation methods were REML and the sample size n = 91 \n(see Figure 3 for the graphs). Akaike Information Criterion (AIC) estimates the prediction error of the amount of \ninformation lost in the model and establishes the quality of the model. This data was collected over a three-year \nperiod, 2016 – 2018, on the Welgevonden Game Reserve, South Africa. N.S. = not significant at the 5% level \n \n \n \n \n \n \n \n \n \n  Browse \nHerbivore Species F 185.6 \n df 124.7 \n P <0.001 \nBlock Type F 0.08 \n df 125.8 \n P N.S. \nBefore - After F 5.5 \n df 126.2 \n P <0.05 \nHerbivore species x Block Type F 1.2 \n df 124.5 \n P N.S. \nHerbivore species x Before - After F 4.0 \n df 124.6 \n P <0.01 \nBefore - After x Block Type F 0.912 \n df 126.2 \n P N.S. \nHerbivore species x Before - After x Block Type F 1.0 \n df 124.5 \n P N.S. \nYear Wald Z 0.8 \n P N.S. \nSite Wald Z 0.4 \n P N.S. \nAIC  1126.2 \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n10 \n \nTable 3. Percentage change in the amount of browse and graze fragments in the diet of each individual free-\nroaming herbivore species (viz. impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros), \ncommon eland (Taurotragus oryx), Burchell’s zebra (Equus quagga burchellii) and the blue wildebeest \n(Connochaetes taurinus), per game lick block type collected over a three-year period, 2016 – 2018, in the \nWelgevonden Game Reserve, South Africa  \n \nThere were particularly large differences in the number of browse species utilised by the impala and Burchell’s \nzebra after the additional of PEG in their diet. The number of browse species utilised increased by 181% in \nimpala and 194% in Burchell’s zebra (supporting information D, E and Table 3). There was an increase in the \ntotal fragments of browse found in the faeces of Burchell’s zebra, kudu, impala and common eland after the \nutilization of PEG, compared with the standard lick block. Wildebeest was the only species with a decrease in \ntotal fragments of browse after the addition of PEG (Table 3).   \nFor Burchell’s zebra we found a significant change in their diet from grass to browse with the utilisation of \nPEG, from a diet of 8% browse to 35% browse with an increase from 16 to 31 different browse species, \nincreasing the use of less palatable species (Supporting Information D, E and Table 3). There was an increase in \nthe utilisation of browse after the use of the standard game lick blocks but not nearly as large as that after the \naddition of PEG. \nDiet composition  \nThe changes in diet composition in terms of the different browse and grass species for the five species of \nherbivores after the introduction of the standard game lick blocks and PEG game lick blocks are shown in \nFigure 3, with ‘Panel a’ encompassing the grass species results and ‘Panel b’ the browse species results. \n  Browse Graze \nSpecies \nLick block type \nNo. Browse species fragments \nbefore lick block deployment \nNo. Browse species fragments \nafter lick block deployment \n% Browse species fragments \nbefore lick block deployment \n% Browse species fragments \nafter lick block deployment \nChange in browse utilisation \nNo. Graze species fragments \nbefore lick block deployment \nNo. Graze species fragments \nafter lick block deployment \n% Graze species fragments \nbefore lick block deployment \n% Graze species fragments after \nlick block deployment  \nChange in graze utilisation \nBurchell's zebra PEG 44 314 8% 35% 27% 519 577 92% 65% -27% \n STD 141 196 16% 32% 17% 757 412 84% 68% -17% \n \nBlue wildebeest PEG 49 31 10% 4% -6% 447 761 90% 96% 6% \n STD 59 50 6% 8% 2% 881 550 94% 92% -2% \n \nGreater kudu PEG 385 779 99% 99% 0% 5 7 1% 1% 0% \n STD 778 513 88% 86% -2% 104 84 12% 14% 2% \n \nImpala PEG 106 316 18% 45% 27% 487 381 82% 55% -27% \n STD 281 220 31% 37% 5% 615 380 69% 63% -5% \n \nCommon eland PEG \nSTD \n397 \n688 \n560 \n591 \n99% \n99% \n93% \n99% \n-6% \n0% \n3 \n9 \n39 \n8 \n1% \n1% \n7% \n1% \n6% \n0% \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n11 \n \nA \n  \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n             B \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n12 \n \nFigure 3. Diagrams of the first two axes of the Principal Components Analysis based on (Panel a) the grass \nspecies and (Panel b) the browse species in the diets of the five free-roaming herbivore species ( viz. impala \n(Aepyceros melampus), greater kudu (Tragelaphus strepsiceros), common eland (Taurotragus oryx), Burchell’s \nzebra (Equus quagga burchellii) and the blue wildebeest (Connochaetes taurinus) before and after the \nutilization of the Standard (STD) game lick blocks or Polyethylene glycol (PEG) game lick blocks. Every dot \nrepresents the combined diet of a herbivore species before or after the addition of the standard game lick blocks \nor the PEG game lick blocks. The location of these dots is determined by the plant species composition of the \ndiet and the abundance of that plant species that was consumed, so dots close to each other have more similar \ndiets than dots further apart. The red arrows show changes in diet following the application of the PEG game \nlick blocks, whereas the green arrows refer to the changes in diet after the deployment of STD blocks. The blue \narrows show the gradients in the foraging ratings (in panel a; classes low and intermediate are merged and \nshown as “LowInter”) and palatability (in panel b; classes low and average are merged and shown as \n“LowAver”) in the diet. Abbreviations: A = After; B = Before; S = STD; P = PEG; E = Eland; I = Impala; K = \nKudu; W = Wildebeest and Z = Zebra. The faecal samples were collected over a three-year period, 2016 – 2018, \nin the Welgevonden Game Reserve, South Africa \n \nAll five-herbivore species had a greater change in browse species utilisation after the addition of PEG when \ncompared to standard game lick blocks, with a noteworthy effect on the diet of Burchell’s zebra and impala \n(Panel b). After the addition of PEG, the number of different browse species utilised in the diet of the common \neland, impala, greater kudu and Burchell’s zebra increased. Before the deployment of the game lick blocks eland \nhad similar diets in the study areas however after the addition of PEG the number of browse species utilised \nsignificantly increased identifying a notable shift in the diet of the eland exposed to PEG. The figure also shows \nthat the changes in the diet after the application of the PEG game lick blocks are more significant than the \nchanges after the deployment of the standard game lick blocks in all five-herbivore species (Panel b).  \nFor the standard game lick blocks, there was no significant change in the percentage of browse diet of the \nimpala (mixed feeder, eating both grass and browse). There was a slight change in favour of the utilisation of \nnormally unpalatable browse species. After the introduction of the PEG game lick blocks, there was a large \nchange in the percentages of browse species utilised and an increase in the utilisation of browse species that had \nlow palatability. \nThe greater kudu and common eland had no major change in their diet of grass and browse with the addition of \nthe standard game lick blocks. After the consumption of PEG there was a major increase in the utilisation of \nbrowse with higher secondary compounds. For blue wildebeest there was no substantial change in their diet \nbetween grass and browse neither with nor without the introduction of the standard game lick blocks or PEG \ngame lick blocks (Figures 2 and 3, and Supporting Information D and E).  \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n13 \n \nMinerals in the faeces \nThere were minor comparative differences found in the mineral concentrations in the faeces of the five species \nof herbivore after utilising either the standard game lick block or the game lick block with the addition of PEG \n(Figure 4, Table 4). The average concentration of N found in the faeces of the common eland, blue wildebeest \nand Burchell’s zebra was higher after the utilization of the PEG game lick block, as was the average \nconcentration of P in the faeces of the common eland, greater kudu and blue wildebeest, compared with the \nstandard lick block (Supporting Information F). However, this difference was only statistically significant in the \nconcentration of P in the faeces of the blue wildebeest. Impala was the only species that showed statistically \nsignificant higher levels of N and P after the utilisation of the standard game lick blocks over the PEG game lick \nblocks (Figure 4, Table 4). The concentration of Ca, S, Cu and B was significantly higher in the common eland \nafter the utilisation of the PEG game lick blocks compared with the standard game lick blocks. \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n14 \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n15 \n \nFigure 4. Mineral values in the faeces of the five-herbivore species ( viz. impala (Aepyceros melampus), greater \nkudu (Tragelaphus strepsiceros), common eland (Taurotragus oryx), Burchell’s zebra (Equus quagga \nburchellii) and the blue wildebeest (Connochaetes taurinus) showing the effect of the availability of \nPolyethylene glycol (PEG) game lick blocks or Standard (STD) game lick blocks. The analysis of the minerals \nin the faeces samples were either recorded as a percentage as in the case of N, Ca, Mg, K, S and P or as mg/kg \nas with Na, Fe, Mn, Cu, Zn and B. Mineral values in the faeces are a measure of nutrient concentrations in the \ndiet. Error bars represent the standard error of the mean. Letters indicate significant differences in \nconcentrations of a mineral between the five herbivore species faeces and the star indicates the statistically \nsignificant differences in the mineral values of the faeces between the PEG and STD game lick blocks within \nthe same herbivore species, in the treatments based on Šidák multiple comparisons tests using a linear mixed \nmodel (Table 4). The faecal samples were collected over a three-year period, 2016 – 2018, in the Welgevonden \nGame Reserve, South Africa \nTable 4. Results of the linear mixed model for differences in minerals in the faeces between the Standard (STD) \nand Polyethylene glycol (PEG) game lick blocks (“block type”) for the five herbivore species ( viz. impala \n(Aepyceros melampus), greater kudu (Tragelaphus strepsiceros), common eland (Taurotragus oryx), Burchell’s \nzebra (Equus burchellii) and the blue wildebeest (Connochaetes taurinus). Year and Site were the random \nfactors, estimation methods were REML and the sample size n = 648 (see Figure 4 for the graphs). Akaike \nInformation Criterion (AIC) estimates the prediction error of the amount of information lost in the model and \nestablishes the quality of the model. This data was collected over a three-year period, 2016 – 2018, on the \nWelgevonden Game Reserve, South Africa. N is nitrogen, P is phosphorus, Ca is calcium, Na is sodium, and \nN.S. is not significant at the 5% level \n  N P Ca Na \nHerbivore species F 163.9 85.0 273.9 12.2 \n df 634.3 634.2 631.2 633.4 \n P <0.001 <0.001 <0.001 <0.001 \nBlock Type F 0.04 0.03 2.3 7.2 \n df 637.7 637.6 617.2 636.3 \n P N.S. N.S. N.S. <0.01 \nHerbivore species x \nBlock Type \nF 3.4 2.3 1.0 0.1 \n df 634.5 634.8 633.0 634.3 \n P <0.01 <0.01 N.S. N.S. \nYear Wald Z 1.0 1.0 0.6 0.9 \n P N.S. N.S. N.S. N.S. \nSite Wald Z 0.7 0.9 1.3 1.0 \n P 0.507 0.388 0.197 N.S. \nAIC  971.7 -1491.5 541.4 9911.7 \n  Mg K S Fe \nHerbivore species F 92.7 121.2 193.1 49.8 \n df 634.6 634.2 633.2 634.6 \n P <0.001 <0.001 <0.001 <0.001 \nBlock Type F 0.09 0.2 0.1 3.1 \n df 636.8 637.9 634.7 637.3 \n P N.S. N.S. N.S. <0.10 \nHerbivore species x \nBlock Type \nF 0.7 2.1 2.2 0.3 \n df 635.1 634.4 633.6 635.2 \n P N.S. <0.10 <0.10 N.S. \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n16 \n \nYear Wald Z 0.9 0.9 0.8 0.9 \n P N.S. N.S. N.S. N.S. \nSite Wald Z 1.2 1.6 1.1 1.1 \n P N.S. N.S. N.S. N.S. \nAIC  -1351.1 159.3 -335.8 10883.7 \n  Mn Cu Zn B \nHerbivore species F 144.4 134.7 20.7 382.4 \n df 633.8 633.5 633.0 634.2 \n P <0.001 <0.001 <0.001 <0.001 \nBlock Type F 0.08 1.3 0.4 7.2 \n df 635.2 635.3 626.4 636.6 \n P N.S. N.S. N.S. <0.01 \nHerbivore species x \nBlock Type \nF 1.2 2.3 1.3 3.7 \n df 634.0 633.2 634.7 635.0 \n P N.S. <0.1 N.S. <0.01 \nYear Wald Z 0.8 1.0 0.7 1.0 \n P N.S. N.S. N.S. N.S. \nSite Wald Z 1.3 0.3 0.9 1.1 \n P N.S. N.S. N.S. N.S. \nAIC  8693.5 3657.9 6050.5 3946.8 \nDiscussion \nLarge herbivores in nutrient poor savannas have to deal with vegetation that generally has low nutrient \nconcentrations, and hence low forage quality (Parker 2004; Mramba et al. 2018). These large herbivores, which \nare subjected to poor forage quality, coupled with high condensed tannins seem to have little access to large \namounts and varieties of food, especially during the dry winter months, and thus are found to have low \nreproduction and survival rates in Welgevonden Game Reserve (Parker 2004; Nguyen et al. 2005; Hassanpour \net al. 2011; Texeira et al. 2012; Mr. J Swart, 2020. Welgevonden Game Reserve, personal communication).  \nThe hypothesis tested that deploying game lick blocks with PEG, compared to the standard game lick blocks, in \na nutrient poor savanna will result in a broadening of herbivore diet, with higher percentages of browse species \nand increased utilisation per browse species that have high levels of condensed tannins and generally low to \naverage palatability. With the addition of PEG, there was an increase in the utilisation of browse species in the \ndiets of the common eland, impala, greater kudu and Burchell’s zebra on Welgevonden Game Reserve. The \nincrease in the percentage of browse utilised was particularly significant in the diet of Burchell’s zebra and \nimpala. The expectation was that the effect on the dietary choices would have had a greater impact on herbivore \nspecies that are browsers than on herbivore species that are grazers, as secondary compound level (tannins) in \nbrowse vegetation is generally higher than grasses (Barroso et al. 2001). However, we show that Burchell’s \nzebra (a grazer) and impala (a mixed feeder) have the largest change in diet selection after the addition of PEG, \nincluding a significant shift in vegetation choice from grass to browse. This change in diet due to PEG has \npotential further repercussions for the vegetation on Welgevonden Game Reserve due to the change in foraging \nbehaviour. The implication is that larger amounts of browse could potentially be utilised, especially during the \ndry months than would normally be, resulting in a potential long-term decrease in closed woodlands to more \nopen woodland system. Blue wildebeest (a grazer) had a decrease in the utilisation of browse after the addition \nof PEG in their diet, alluding to the fact that the effect of PEG may be species specific to the herbivore, specific \nto individual species dietary requirements or a combination of both.  \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n17 \n \nWith the addition of PEG, there is a general increase in the utilisation of vegetation with high tannin contents \nwith medium and lower palatability ratings for the common eland, impala, greater kudu and Burchell’s zebra: \nthe changes in the diets are positively correlated with the low and intermediate grazing rating and the low and \naverage palatability of the individual plant species. It is shown in other studies on domestic animals that the \naddition of PEG to the diet does affect diet choice (Foley and Hume 1987; Marsh et al. 2003; Jansen et al. 2007; \nMkhize et al. 2015; Mkhize et al. 2016), which collaborates with our findings for free-roaming herbivores in a \nnutrient poor savanna. \nIt can be deduced that PEG has a significant effect on the broadening of the diet choices of four of the five free-\nroaming herbivores on Welgevonden Game Reserve. The change in diet of these four free-roaming herbivores \nsupports the findings of studies on penned animals that show that tannins act as both digestibility reducers and \nfeeding deterrents that negatively affect intake (Mkhize et al. 2015) and for which PEG has been shown to \nreduce these adverse effects (Salawu et al. 1997; Landau et al. 2003). For blue wildebeest, classified as a grazer, \nthere was no substantial change in their diet between graze and browse neither with nor without the introduction \nof the standard game lick blocks or PEG game lick blocks (Figures 2 and 3, and Supporting Information D and \nE).  \nWe tested a further hypothesis to analyse if the change in diet, due to the addition of game lick blocks with and \nwithout the addition of PEG, had an effect on the concentration of minerals within the faeces of the five free-\nroaming herbivores. Despite the changes in diet after the utilisation of PEG, there was minimal variation \nbetween the levels of N and P in the faeces for the majority of herbivore species. The exceptions were the \nimpala where N and P in the faeces were lower than the standard lick block after the utilisation of PEG, and for \nblue wildebeest which showed increases in faecal N and P after utilisation of PEG. Faecal nutrient content \nanalyses are useful as short-term indicators of diet selection and nutrient status of free-roaming herbivores \n(Botha and Stock 2005; Codron et al. 2005). Grant et al. (2000) posit that faecal N levels can indicate a dietary \ndeficiency which may precipitate nutritional stress, while faecal P levels indicate a deficiency that may lead to \nlow reproductive rates in herbivores. Although the diet choices for common eland, greater kudu, impala and \nBurchell’s zebra broadened when PEG game lick blocks were introduced, there was no clear differences in the \nminerals in the faeces. Given the nutritional differences between the plant species, a possible explanation for \nthese results is that the animals absorbed and utilised the extra nutrients consumed from their broader diet, \nwhich is necessary for survival in such nutrient poor environments (Parker 2004; Putman and Staines 2004; \nTexeira et al. 2012). Rainfall tends to reduce forage quality and the area becomes dominated by grass species \nwith lower leaf N and P concentrations (Hopcraft et al. 2012). N and P concentrations in dry faeces of ruminants \nbelow the threshold of potential concern values of 1.2% and 0.25%, respectively (Prins 1996; Wrench et al. \n1997; Grant et al. 2011), would constitute an exceedance of these thresholds and would be a concern for animal \nsurvival. Based on the N and P faeces threshold values of Wrench et al. (1997) and Grant et al . (2000), the \nBurchell’s zebra is the only animal with a concern pertaining to N in the study area, and the impala after \nutilising PEG is the only species with no concern pertaining to P (Supporting Information F). This shows that \nthe addition of N and P to a nutrient poor system is imperative for the long-term survival of free-roaming \nherbivore species. Furthermore, when looking at the individual minerals identified in the faecal analysis in the \nfive study animals, the two grazers (Burchell’s zebra and blue wildebeest), have the lowest amount of minerals \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n18 \n \navailable to them suggesting if the addition of minerals into a nutrient poor savanna is considered, the minerals \nshould be applied to grass land areas which would be more accessible to the grazer species. \nPractical implications \nOur study has shown that with the use of polyethylene glycol (PEG), four of the five free-roaming wild \nherbivores (viz. common eland, impala, greater kudu and Burchell’s zebra) in a nutrient poor savanna are able to \nutilise a greater number of otherwise less palatable tree species with higher levels of condensed tannins. This \ncould allow these herbivore species to obtain more nutrients and energy from the nutrient poor diet, especially \nduring the dry season, when many of the female herbivores in this dystrophic savanna are gravid. Alleviating the \neffects of food limitation by providing PEG may have a positive repercussion on fecundity levels. Our study \nconcurs with the findings of Scogings et al. (2014) who stated that browsers and mixed feeders foraging \npreferences are strongly shaped by secondary compounds, however our findings confirms that this is also the \ncase with Burchell’s zebra, which had a significant shift in diet from graze to browse. Our experiments thus \npotentially strengthen the ability of wild free-roaming wild herbivores to forge the critical link in the chain of \nreasoning between individual performance and individual food limitation on the one hand and population \nlimitation and population dynamics on the other hand. This concurs with findings by Decandia et al. (2000) and \nMkhize et al. (2015, 2016, 2018), who used PEG in feed trials with goats, where they concluded that PEG can \nimprove the nutritive value of the feed and hence optimising the goat’s performance. These results lead to the \nconclusion that PEG is a valuable addition to the diet of the free-roaming wild herbivore species we studied. \nThese findings contribute to a better understanding of the diet of large herbivores in nutrient poor savannas and \nhow management can act to improve foraging conditions, more especially in the dry months. In order to \nconclusively prove that PEG can break food limitation, additional information is required through further \nresearch to establish birth and survival rates, coupled with body condition change, of herbivores which have and \nhave not utilised PEG in their diet. \n \n \n \n \n \n \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n19 \n \nSUPPORTING INFORMATION \nSupporting Information A. Standard Game Lick Block Composition (25kg blocks) as reported by the \nmanufacturer WES Feeds (Thabazimbi, South Africa) (WES Feeds 2019) \nNutrient Minimum Maximum Unit \nProtein 150  g/kg \nCalcium 15  g/kg \nPhosphorus 8  g/kg \nMagnesium 6  g/kg \nSulphur 6  g/kg \nManganese 200  mg/kg \nCopper  40 mg/kg \nCobalt  0.5 mg/kg \nIron  100 mg/kg \nIodine  2 mg/kg \nZinc  350 mg/kg \nSelenium  1 mg/kg \nVitamin A 20000  iu/kg \nVitamin E 30  iu/kg \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n20 \n \nSupporting Information B. Browse species located in the faeces with their digestibility ratings. The \ndigestibility ratings were established through the use of the field guide to trees of Southern Africa (Van Wyk \nand Van Wyk 1997) and through the independent advice of experts in the field (Dr R. Grant \n(https://orcid.org/0000-0002-8419-5209), Dr M. Peel (https://orcid.org/0000-0003-1284-3665), Dr H. \nBezuidenhout (http://orcid.org/0000-0002-6519-7321), Professor N. Owen-Smith (https://orcid.org/0000-0001-\n8429-1201), Professor K. Eloff (https://orcid.org/0000-0003-1494-9842), Mr J. Swart (Welgevonden Game \nReserve Ecologist) and Mr G. Canning (https://orcid.org/0000-0001-6100-9541). The “X” in the table refers to \nthe median when referring to the digestibility of these browse species for wild herbivores in the study area as \ndescribed by the independent experts \nBrowse Species Infrequently \nconsumed by a few \nintermediate feeders \nand browsers  \nOften consumed by \nsome intermediate \nfeeders and browsers \nVery often consumed \nby many different \nintermediate feeders \nand browsers  \nSenegalia burkei   X \nVachellia karoo  X  \nApodytes dimidiata X   \nBauhinia petersiana X   \nBerchemia zeyheri   X \nBrachylaena rotundata X   \nBurkea africana X   \nClerodendrum glabrum X   \nClutia pulchella  X   \nCombretum apiculatum  X  \nCombretum hereroense  X  \nCombretum nelsonii X   \nCombretum zeyheri  X  \nCryptolepis oblongifolia X   \nCussonia spicata X   \nDichapetalum cymosum  X   \nDichrostachys cinerea  X  \nDiplorhynchus \ncondylocarpon \n X  \nDombeya rotundifolia X   \nEhretia rigida   X  \nElephantorrhiza burkei X   \nEnglerophytum \nmagalismontanum \nX   \nErythrina lysistemon X   \nEuclea crispa X   \nEuclea linearis X   \nEuclea natalensis X   \nFaurea saligna X   \nFlueggea virosa  X  \nGardenia volkensii   X \nGrewia bicolor   X \nGrewia flavescens  X  \nGymnosporia tenuispina X   \nIndigofera melanadenia X   \nJasminum multipartitum X   \nLannea discolor X   \nLannea edulis X   \nLippea javanica  X  \nMaytenus undata X   \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n21 \n \nMundulea sericea  X  \nOchna pulchra X   \nOzoroa paniculosa X   \nOzoroa sphaerocarpa X   \nParinari capensis  X  \nPavetta gardeniifolia X   \nPellaea calomelanos X   \nPeltophorum africanum X   \nProtea caffra X   \nProtea welwitschii X   \nPseudolachnostylis \nmaprouneifolia \n X  \nPsydrax livida X   \nPterolobium stellatum X   \nRhoicissus tridentata X   \nSearsia pyroides X   \nSpirostachys africana  X  \nStrychnos pungens  X  \nSyzygium cordatum X   \nSyzygium guineense X   \nTarchonanthus camphoratus   X  \nTarenna supra-axillaris X   \nTerminalia brachystemma X   \nTurraea obtusifolia X   \nVangueria infausta  X  \nWaltheria indica X   \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n22 \n \nSupporting Information C. Grass species found in the faeces with their grazing values obtained from the guide \nto grasses of Southern Africa (Van Oudtshoorn 2002). The “X” in the table refers to the median when referring \nto the digestibility of these grass species for wild herbivores in the study area as described by Van Oudtshoorn, \n2002. ‘Grazing value’ is generally not known for wild herbivores with their different physiologies. The reported \ngrazing values in this Table reflect more than a century of experiential knowledge form graziers in Southern \nAfrica. Wildlife managers in Southern Africa have found these assessments generally useful for many of the \nwild grazers \nGrass Species Grazing value low Grazing value \naverage \nGrazing value high \nAndropogon chinensis  X  \nAristida sp X   \nBrachiaria brizantha  X  \nBrachiaria serrata  X  \nCenchrus ciliaris   X \nChloris pycnothrix X   \nChloris virgata  X  \nChrysopogon serrulatus   X \nCynodon dactylon   X \nDactyloctenium aegyptium  X  \nDigitaria eriantha   X \nDiheteropogon amplectens  X  \nEragrostis sp  X  \nHeteropogon contortus  X  \nHyparrhenia filipendula  X  \nHyparrhenia hirta  X  \nHyperthelia dissoluta   X  \nImperata cylindrica  X   \nLeersia hexandra   X \nLoudetia simplex  X  \nMelinis nerviglumis  X  \nMelinis repens X   \nMicrochloa caffra X   \nMonocymbium ceresiiforme  X  \nPanicum dregeanum  X  \nPanicum maximum   X \nPanicum natalense X   \nPaspalum scrobiculatum  X  \nPaspalum urvillei  X  \nPogonarthria squarrosa X   \nSacciolepis typhura X   \nSchizachyrium jeffreysii X   \nSchmidtia pappophoroides   X \nSetaria lindenbergiana   X \nSetaria pumila X   \nSetaria sphacelata   X \nSporobolus pyramidalis X   \nThemeda triandra  X  \nTrachypogon spicatus X   \nTriraphis schinzii X   \nTristachya biseriata  X  \nUrelytrum agropyroides X   \nUrochloa mosambicensis   X \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n23 \n \nSupporting Information D. Diet change in browse after the utilization of game lick blocks with and without the supplementation of Polyethylene Glycol (PEG), for the five-\nherbivore species, impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros), common eland (Taurotragus oryx), Burchell’s zebra (Equus quagga burchellii) \nand blue wildebeest (Connochaetes taurinus). In the Table, PEG refers to game lick blocks supplemented with Polyethylene Glycol. STD (for ‘standard’) refers to game lick \nblocks without PEG. PRE (for ‘prior’) refers to the analysis prior to the supplementation of PEG. POS (for ‘post’) refers to the analysis after the supplementation of PEG. \nThe numbers in the Table refer to the number of each individual plant species found in the faeces of each animal species before or after the utilisation of PEG or STD lick \nblocks \nDigestibility Browse species Burchell's zebra Blue wildebeest Greater kudu Impala Common eland \n  PEG STD PEG STD PEG STD PEG STD PEG STD \n  PR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nHigh Senegalia burkei  2       2 6   1 7 1   17 10 1 \nIntermediate Vachellia karoo          4           \nLow Apodytes dimidiata          3           \nLow Bauhinia petersiana  4                   \nHigh Berchemia zeyheri                   1  \nLow Brachylaena \nrotundata \n         1           \nLow Browse unknown 6 38 19 21 5 4 7 6 37 89 90 46 8 30 24 19 35 51 76 63 \nLow Burkea africana  27 10 4 4 8 1 2 4 25 46 12 2 14 3 5 8 32 22 18 \nLow Clerodendrum \nglabrum \n         1        2  1 \nLow Clutia pulchella  1         8  1      2  3 \nIntermediate Combretum \napiculatum \n         4  4    1   3 2 \nIntermediate Combretum \nhereroense \n         2    6    1 1  \nLow Combretum nelsonii 4 1 1 1   1  9 12 20 17  4 4 2 10 15 33 12 \nIntermediate Combretum zeyheri  2    1   3 19 11 11  3 4 2  27 11 9 \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n24 \n \nLow Cryptolepis \noblongifolia \n 2       31 15 20 24  2   11 37 11 25 \nLow Cussonia spicata                 7    \nLow Dichapetalum \ncymosum (Gifblaar) \n1 5 1 5      6 1 1  4      2 \nIntermediate Dichrostachys \ncinerea \n1 5  7 2   6 32 21 58 35 30 33 116  64 70 19 83 17 \nIntermediate Diplorhynchus \ncondylocarpon \n9 93 60 64  1  1 6 73 16 43  5 2 12 4 13 10 50 \nLow Dombeya \nrotundifolia \n1 1 1 5    1 17 32 8 20 7 12 9 12 18 6 17 24 \nIntermediate Ehretia rigida    5       4 3          \nLow Elephantorrhiza \nburkei \n1 7 2 5 14 6 25 5 20 44 71 16  2  7 24 34 53 33 \nLow Englerophytum \nmagalismontanum \n 7  3      35 2 12 1 18 2 5 4 18  19 \nLow Erythrina lysistemon   1      20 12 35 7  1  1 4 6 15 1 \nLow Euclea crispa 1 1 2 1   3  11 10 11 6  3 6 3  3 7 2 \nLow Euclea linearis         1 4     1  2    \nLow Euclea natalensis         3  3       2   \nLow Faurea saligna 1        2   3         \nIntermediate Flueggea virosa            1         \nHigh Gardenia volkensii             1     3   \nHigh Grewia bicolor  3      1  12  10    1  9 6 11 \nIntermediate Grewia flavescens  3      3 22 24 42 21 13 13 2 5 34 11 42 69 \nLow Gymnosporia \ntenuispina \n 1                   \nLow Indigofera \nmelanadenia \n1 7 2 9 2 6 6 7 41 68 58 28 8 46 17 18 45 74 39 30 \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n25 \n \nLow Jasminum \nmultipartitum \n 1       6 28 26 23 1 5 8 7 18 13 37 12 \nLow Lannea discolor           1       7   \nLow Lannea edulis  1                   \nIntermediate Lippea javanica 3 10 2 5   5 6  9 8 11 6 3 5 3  11 16 8 \nLow Maytenus undata          1 6 2       4  \nIntermediate Mundulea sericea    1      20 5 6  3 7 4  5 4 3 \nLow Ochna pulchra  2 2      1 9 3 2  4 1   3  5 \nLow Ozoroa paniculosa        1  5  7    2   1 1 \nLow Ozoroa \nsphaerocarpa \n         4         8  \nIntermediate Parinari capensis         2 1  7    1    3 \nLow Pavetta gardeniifolia      1             4  \nLow Pellaea calomelanos  2  3   2  1  2 4 2 1 6 3   2  \nLow Peltophorum \nafricanum \n 3       5 16 31   5 1 1 13 9 37 5 \nLow Protea caffra                   1  \nLow Protea welwitschii 5 2 5  7  3  13 4 19 10 10  12 1 11 8 11 2 \nIntermediate Pseudolachnostylis \nmaprouneifolia \n         1 20 5     2 5   \nLow Psydrax livida                    3 \nLow Pterolobium \nstellatum \n1 1 2 1 11  2  55 29 70 10   5 2 44 30 53 35 \nLow Rhoicissus tridentata  3                   \nLow Searsia pyroides   6      1            \nIntermediate Spirostachys \nafricana \n        4 4 10 13  14 1 3 1 6 5 17 \nIntermediate Strychnos pungens 5 52 13 52  3  1 5 44 2 50  44 1 16 2 21 3 34 \nLow Syzygium cordatum  12 4   1    1           \nLow Syzygium guineense          1         2  \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n26 \n \nIntermediate Tarchonanthus \ncamphoratus  \n 6 1 5 1  2 2 16 17 49 16 2 5 2 2 9 10 13 13 \nLow Tarenna supra-\naxillaris \n       3 1 8  12  1 3 2  4 6 9 \nLow Terminalia \nbrachystemma \n         1           \nLow Turraea obtusifolia          1           \nIntermediate Vangueria infausta 3 10 1 4 2  1 2 9 30 13 10 5 21 13 8 9 38 17 34 \nLow Waltheria indica   1  1  1 3 5 11 18 7 9 7 25 8 12 8 24 15 \n Total number of \nbrowse species \nconsumed \n16 31 21 18 10 9 13 16 31 48 33 37 16 29 27 30 24 36 37 36 \n Total number of \nindividual species \nbrowsed \n44 314  141 196 49 31 59 50 385  779 778 513 106 316 281 220 397 560 688 591 \n \n \n \n \n \n \n \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n27 \n \nSupporting Information E. Diet change in grass choice after the utilization of game lick blocks with and without the supplementation of Polyethylene Glycol, for the five-\nherbivore species, impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros), common eland (Taurotragus oryx), Burchell’s zebra (Equus quagga burchellii) \nand the blue wildebeest (Connochaetes taurinus). In the Table, PEG refers to game lick blocks supplemented with Polyethylene Glycol. STD (for ‘standard’) refers to game \nlick blocks without PEG. PRE (for ‘prior’) refers to the analysis prior to the supplementation of PEG. POS (for ‘post’) refers to the analysis after the supplementation of PEG. \nThe numbers in the Table refer to the number of each individual plant species found in the faeces of each animal species before or after the utilisation of PEG or STD lick \nblocks \nGrazing \nvalue \nGraze species Burchell's zebra Blue wildebeest Greater kudu Impala Common eland \n  PEG STD PEG STD PEG STD PEG STD PEG STD \n  PR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nPR\nE \nPO\nS \nAverage Andropogon \nchinensis \n37 19 51 18 11 12 12 28    1 17 10 10 7  2   \nLow Aristida sp 90 110 111 95 70 103 101 73 3 1 13 13 58 39 81 53 1 3 4 1 \nAverage Brachiaria \nbrizantha \n  10                  \nAverage Brachiaria \nserrata \n20 3 6 8 1 13 6 7    2 13 3 7 5     \nHigh Cenchrus ciliaris 1 1 1 1 3 2 1              \nLow Chloris \npycnothrix \n12 9 6 7  3 20 7   1  8 5 8 4  5  1 \nAverage Chloris virgata     7  1        2      \nHigh Chrysopogon \nserrulatus \n1  1  1 3 5      5  1      \nHigh Cynodon dactylon 42 55 91 25 51 102 81 63  1 20 13 59 61 70 46 1 4  3 \nAverage Dactyloctenium \naegyptium \n 13 1  3 3 5 1     3 8 6 8     \nHigh Digitaria \neriantha \n20 7 4 12 3 15 2 5     4 4 3 1     \nAverage Diheteropogon \namplectens \n5 2 1  2        2        \nAverage Eragrostis sp 148 196 247 147 189 323 409 224 1 2 34 29 186 185 232 181  11 3 1 \nLow Grass unknown 36 37 52 21 26 36 47 29 1  6 4 18 22 41 18  1 1  \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n28 \n \nAverage Heteropogon \ncontortus \n16 43 27 17 9 39 79 21  2 5 6 3 9 17 8 1 5   \nAverage Hyparrhenia \nfilipendula \n4  1          5        \nAverage Hyparrhenia \nhirta \n   1                 \nAverage Hyperthelia \ndissoluta  \n1            1        \nLow Imperata \ncylindrica  \n  2  4 1 5 2    1 1  1      \nHigh Leersia hexandra  2 3 3  7 5 9    5 1  2 4  1   \nAverage Loudetia simplex 1  1 1 1 1               \nAverage Melinis \nnerviglumis \n  2 1   1    2   1 2      \nLow Melinis repens 22 24 29 23 23 31 24 29  1 5 5 25 9 30 12  3  1 \nLow Microchloa caffra      1 2    1  2        \nAverage Monocymbium \nceresiiforme \n 3 3 1 5 1 3 1     5        \nAverage Panicum \ndregeanum \n  2                  \nHigh Panicum \nmaximum \n27 8 33 6 4 15 21 21   1 3 22 3 28 6  2   \nLow Panicum \nnatalense \n  2   13       1   1     \nAverage Paspalum \nscrobiculatum \n5 10 11 3 3 7 10 3     2 3 6   2   \nAverage Paspalum urvillei  1    2  1    2  1       \nLow Pogonarthria \nsquarrosa \n            1        \nLow Sacciolepis \ntyphura \n 3 1  1 3 2 2       1      \nLow Schizachyrium \njeffreysii \n1  5  2  2      1  4      \nHigh Schmidtia \npappophoroides \n8 6 14 7 3 9 21 7   15  8 1 38 3   1 1 \nHigh Setaria \nlindenbergiana \n 12  1          10       \nLow Setaria pumila 1               2     \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n29 \n \nHigh Setaria \nsphacelata \n8 8 7 2 2 9 1 6     6 2 7 3     \nLow Sporobolus \npyramidalis \n2            1        \nAverage Themeda triandra 41 5 29 9 18 5 11 11     26 5 14 18     \nLow Trachypogon \nspicatus \n3      1              \nLow Triraphis schinzii   1 1 2 1 3        2      \nAverage Tristachya \nbiseriata \n2   2                 \nLow Urelytrum \nagropyroides \n     1               \nHigh Urochloa \nmosambicensis \n2  2  3      1  3  2      \n Total number of \ngrass species \nconsumed \n27 23 32 24 26 28 28 21 3 5 12 12 29 19 25 18 3 11 4 6 \n Total number of \nindividual \nspecies grazed \n583 577 757 412 447 761 881 550 5 7 104 84 487 381 615 380 3 39 9 8 \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n  30 \nSupporting Information F. Average percentage (with the 95% confidence intervals) of N- and P-\nconcentrations found in the faeces for the five-herbivore species, impala ( Aepyceros melampus), greater kudu \n(Tragelaphus strepsiceros), common eland (Taurotragus oryx), Burchell’s zebra (Equus quagga burchellii) and \nblue wildebeest (Connochaetes taurinus), following the use of game lick blocks with PEG (= PEG) or standard \ngame lick blocks (= STD) \nHerbivore species Average N-PEG Average N-STD Average P-PEG Average P-STD \nCommon eland 2.35 (±0.40) 2.17 (±0.14) 0.22 (±0.02) 0.21 (±0.01) \nImpala 2.10 (±0.07) 2.30 (±0.20) 0.27 (±0.02) 0.29 (±0.03) \nGreater kudu 2.20 (±0.11) 2.21 (±0.10) 0.22 (±0.01) 0.21 (±0.01) \nBlue wildebeest 1.62 (±0.10) 1.46 (±0.06) 0.25 (±0.02) 0.22 (±0.01) \nBurchell’s zebra 1.05 (±0.05) 1.00 (±0.03) 0.13 (±0.02) 0.13 (±0.01) \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n \n \n31 \n \nReferences \nAugustine  GJ,  Santamaria  F,  Tanaka  K.  2003.  Local calcium signalling in neurons.  Neuron 40:331-346.  \nBadran  AM,  Jones  DE,  1965.  Polyethylene Glycols – Tannins Interaction in Extracting Enzymes. Nature \nInternational Journal of Science 206:622-624. \nBarroso  FG,  Martinez  TF,  Paz  T,  Parra  A,  AlarcÓn  FJ.  2001.  Tannin content of grazing plants of \nsouthern Spanish arid lands. Journal of Arid Environments 49:301-314. \nBotha  MS,  Stock  WD.  2005.  Stable isotope composition of faeces as an indicator of seasonal diet selection in \nwild herbivores in southern Africa. South African Journal of Science 101:371-374. \nCech  PG,  Kuster  T,  Edwards  PJ,  Venterink  HO.  2008.  Effects of herbivory, Fire and N₂-fixation on \nnutrient limitation in a humid African savanna. Ecosystems 11:991-1004. \nCodron  D,  Codron  J,  Lee-Thorp  JA,  Sponheimer  M,  De Ruiter  D.  2005.  Animal diets in the Waterberg \nbased on stable isotopic composition of faeces. African Journal of Wildlife Research 35:43-52.  \nCooper  SM,  Owen-Smith  N.  1985.  Condensed tannins deter feeding by browsing ruminants in a South \nAfrican savanna. Oecologia Journal 67:142-146. \nDecandia  M,  Sitzia  M,  Cabiddu  A,  Kababya  D,  Molle  G.  2000.  The use of polyethylene glycol to reduce \nthe anti-nutritional effects of tannins in goats fed woody species. Small Ruminant Research 38:157-164. \nDe Jong  CB,  Gill  RMA,  Van Wieren  SE,  Burlton  FEW.  1995.  Diet selection in Kielder Forest by roe deer \nCapreolus in relation to plant cover. Forest Ecology Management 79:91-97. \nFoley  WJ,  Hume  ID.  1987.  Digestion and Metabolism of High-Tannin Eucalyptus Foliage by the Brushtail \nPossum (Trichosurus vulpecula) (Marsupialia, Phalangeridae). Journal of Comparative Physiology B-\nBiochemical Systemic and Environmental Physiology  157:67-76. \nGrant  RCC,  Peel  MJS,  Bezuidenhout  H.  2011.  Evaluating herbivore management outcomes and associated \nvegetation impacts. Koedoe 53:1-15. \nGrant  CC,  Peel  MJS,  Zambatis  N,  Van Ryssen  JBJ.  2000.  Nitrogen and phosphorus concentration in \nfaeces: An indicator of range quality as a practical adjunct to existing range evaluation methods. African Journal \nof Range and Forage Science 17:81–92. \nHassanpour  S,  Maheri-Sis  N,  Eshratkhah  B,  Mehmandar  FB.  2011.  Plants and secondary metabolites \n(Tannins): A Review. International Journal of Forest, Soil and Erosion  1:47-53. \nHattas  D.  2014.  Carbon based secondary metabolites in African savanna woody species in relation to anti-\nherbivore defence. PhD thesis, Department of Biological Sciences, University of Cape Town, South Africa. \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n \n \n32 \n \nHopcraft  JGC,  Anderson  TM,  Pérez-Vila  S,  Mayemba  E,  Olff  H.  2012.  Body size and the division of \nniche space: food and predation differentially shape the distribution of Serengeti grazers. Journal of Animal \nEcology 81:201-213.  \nIBM Corp.  Released 2015.  IBM SPSS Statistics for Windows, Version 23.0. Armonk, New York: IBM Corp.  \nJansen  AWAM,  Van Langevelde  F,  De Boer  WF,  Kirkman  KP.  2007.  Optimisation or satiation, testing \ndiet selection rules in goats. Small Ruminant Research 73:160-168. \nLangman  VA.  1978.  Giraffe Pica Behaviour and Pathology as Indicators of Nutritional Stress. The Journal of \nWildlife Management 42:141-147. \nLandau  S,  Xue  B,  Dvash  L,  Friedman  S,  Mabjeesh  SJ.  2003.  Polyethylene glycol, used to alleviate the \nnegative effects of dietary tannins, can also serve as a marker of fecal output in goats. Small Ruminant Research \n48:37-43. \nMajuva-Masafu  MM,  Linington  MJ.  2006.  The effect of Browse Plus on nutrient intake, rumen pH and \ndigestibility of a sole diet of Leucaena leucocephala forage. African Journal of Range and Forage Science \n23:171-175. \nMakkar  HPS,  Blummel  M,  Becker  K.  1995.  Formation of complexes between polyvinyl pyrrolidones or \npolyethylene glycols and tannins, and their implication in gas production and true digestibility in in vitro \ntechniques. British Journal of Nutrition 73:897-913. \nMakkar  HPS,  Sanchez  M,  Speedy  AW.  2007.  Feed Supplementation Blocks. Urea-molasses multinutrient \nblocks: simple and effective feed supplement technology for ruminant agriculture . Food and Agriculture \nOrganization of the United Nations, Rome. \nMarsh  KJ,  Wallis  IR,  Foley  WJ.  2003.  The effect of inactivating tannins on the intake of Eucalyptus foliage \nby a specialist Eucalyptus folivore (Pseudocheirus peregrinus) and a generalist herbivore (Trichosurus \nvulpecula). Australian Journal of Zoology 51:31-42. \nMcDowell  LR,  Arthington  JD.  2005.  Minerals for Grazing Ruminants in Tropical Regions , Mosaic Feed \nIngredients 4th edition. University of Florida. \nMcLeod  MN.  1974.  Plant tannins – their role in forage quality. Nutrition Abstract Review 44:803-815.  \nMkhize  NR,  Heitkönig  IMA,  Scogings  PF,  Dziba  LE,  Prins  HHT,  De Boer  WF.  2015.  Condensed \ntannins reduce browsing and increase grazing time of free-ranging goats in semi-arid savannas. Journal of \nApplied Animal Behaviour Science 169:33-37. \nMkhize  NR,  Heitkönig  IMA,  Scogings  PF,  Hattas  D,  Dziba  LE,  Prins  HHT,  De Boer  WF.  2016.  \nSupplemental nutrients increase the consumption of chemically defended shrubs by free-ranging herbivores. \nAgriculture, Ecosystems and Environments  235:119-126. \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n \n \n33 \n \nMkhize  NR,  Heitkӧnig  IMA,  Scogings  PF,  Dziba  LE,  Prins  HHT,  De Boer  WF.  2018.  Effects of \ncondensed tannins on live weight, faecal nitrogen and blood metabolites of free-ranging female goats in a semi-\narid African savanna. Small Ruminant Research 166:28-34. \nMolyneux  RJ,  Ralphs  MH.  1992.  Plant toxins and palatability to herbivores. Journal of Range Management, \nJanuary 1992. \nMoujahed  N,  Kayouli  C,  Thewis  A,  Beckers  Y,  Rezgui  S.  2000.  Effects of multinutrient blocks and \npolyethylene glycol 4000 supplies on intake and digestion by sheep fed Acacia cyanophylla Lindl. Foliage-\nbased diets. Animal Feed Science and Technology 88:219-238. \nMramba  RP,  Andreassen  HP,  Mlingi  V,  Skarpe  C.  2018.  Activity patterns of African elephants in nutrient-\nrich and nutrient-poor savannas. Mammalian Biology 94:18-24. \nMucina  L,  Rutherford  MC.  2006.  The vegetation of South Africa, Lesotho and Swaziland , Strelitzia 19. South \nAfrican National Biodiversity Institute, Pretoria. \nNguyen  TM,  Binh  DV,  Ørskov  ER.  2005.  Effect of foliage containing condensed tannins and on \ngastrointestinal parasites. Animal Feed Science and Technology 121:77-87. \nParker  AH.  2004.  The vegetation ecology of Welgevonden Private Nature Reserve in the Waterberg Region of \nSouth Africa. Ms Thesis, Department of Science, University of Witwatersrand, Johannesburg, South Africa. \nPrins  HHT.  1996.  Ecology and Behaviour of the African Buffalo: Social inequality and decision , Chapman \nand Hall. London. \nPrins  HHT,  Van Langevelde  F.  2008.  Assembling a diet from different places. In: H. H. T. Prins and F. Van \nLangevelde (eds.) (2008). Resource Ecology: Spatial and Temporal Dynamics of Foraging . Springer, Dordrecht, \nthe Netherlands. \nProvenza  FD,  Burritt  EA,  Perevolotsky  A,  Silanikove  N.  2000.  Self-regulation of intake of polyethylene \nglycol by sheep fed diets varying in tannin concentrations. Journal of Animal Science 78:1206-1212. \nProvenza  FD,  Villalba  JJ,  Haskell  J,  MacAdam  JW,  Griggs  TC,  Wiedmeier  R.  2007.  The value to \nherbivores of plant physical and chemical diversity in time and space. Crop Science 47:382-398. \nPutman  RJ,  Staines  BW.  2004.  Supplementary winter feeding of wild red deer Cervus elaphus in Europe and \nNorth America: justifications, feeding practice and effectiveness. Journal of Mammal Review 34:285-306. \nRoosendaal  B.  1992.  Wildlife nutrition and feeding. accessed 23 February 2020, from \nhttps://www.alzu.co.za/img/WNutrition.pdf . \nSAFARI Feeds.  2019.  South Africa’s leading manufacturer and supplier of specialised block licks and pellets \nfor exotic game animals. accessed 02 March 2019, from www.safarifeeds.co.za. \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint \n\n \n \n34 \n \nSalawu  MB,  Acamovic  T,  Stewart  CS,  Hovell  FD.  1997.  Quebracho tannins with or without Browse Plus \n(a commercial preparation of polyethylene glycol) in sheep diets: effect on digestibility of nutrients in vivo and \ndegradation of grass hay in sacco and in vitro. Journal of Animal Feed Science Technology 69:67-78. \nScogings  PF,  Hjalten  J,  Skarpe  C,  Hattas  D,  Zobolo  A,  Dziba  L,  Rooke  T.  2014.  Nutrient and \nsecondary metabolite concentrations in a savanna are independently affected by large herbivores and shoot \ngrowth rate. Plant Ecology 215:73-82. \nŠmilauer  P,  Lepš  J.  2014.  Multivariate Analysis of Ecological Data using Canoco 5. Cambridge University \nPress, Cambridge CB2 8BS, United Kingdom. \nSmit  GN.  2013.  Grazing capacity – game - Calculation of grazing capacity and browse capacity for game \nspecies’, Econatics environmental management, paragraph 3.6. visited 15 January 2019, \nhttp://www.wildliferanching.com/content/grazing-capacity-game . \nTexeira  M,  Baldi  G,  Paruelo  J.  2012.  An exploration of direct and indirect drivers of herbivore reproductive \nperformance in arid and semi-arid rangelands by means of structural equation models. Arid Environments 81:26-\n34. \nTomlinson  KW,  Van Langevelde  F,  Ward  D,  Prins  HHT,  De Bie  S,  Vosman  B,  Sampaio  EVSB,  Sterck  \nFJ.  2016.  Defence against vertebrate herbivores trades off into architectural and low nutrient strategies \namongst savanna Fabaceae species. Oikos 125:126–136. \nVan Lieverloo  RJ,  Schuiling  BF,  De Boer  WF,  Lent  PC,  De Jong  CB,  Brown  D,  Prins  HHT.  2009.  A \ncomparison of faecal analysis with backtracking to determine the diet composition and species preference of the \nblack rhinoceros (Diceros bicornis minor). European Journal of Wildlife Research 55:505-515. \nVan Oudtshoorn  F.  2002.  Guide to Grasses of Southern Africa, Briza Publications, Pretoria, South Africa. \nVan Wyk  B,  Van Wyk  P.  1997.  Field Guide to Trees of Southern Africa, Struik Publishers, Cape Town, \nSouth Africa. \nWES Feeds.  2019.  Home of Boskos game feed. accessed 13 September 2018, from www.wesenterprises.co.za. \nWrench  JM,  Meissner  HH,  Grant  CC.  1997.  Assessing diet quality of African ungulates from faecal \nanalyses: the effect of forage quality, intake and herbivore species. Koedoe 40:125-136. \n.CC-BY 4.0 International licenseavailable under a \n(which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made \nThe copyright holder for this preprintthis version posted January 23, 2024. ; https://doi.org/10.1101/2024.01.20.576483doi: bioRxiv preprint","source_license":"CC-BY-4.0","license_restricted":false}