Postpartum uterine health, energy metabolism, and fertility of primiparous and multiparous crossbred dairy cows raised in the Amazon biome

Abstract This study aimed to compare the biological activity of the uterus and the metabolism between primiparous and multiparous crossbred dairy cows. Eighteen crossbred dairy cows (B. indicus x B. taurus) were divided by parity order into primiparous (n = 8), and multiparous (n = 10) cows. These cows were evaluated from parturition to 50 days in milk (DIM) for milk production, body weight, body condition score, subcutaneous fat thickness, seric β-hydroxybutyrate, and presence of purulent vaginal discharge. Also, uterine tissue was collected using the cytobrush technique to assess the proportion of polymorphonuclear cells and the abundance of IL-1B, IL-6, IL-8, TNFα, PGR, ESR1, ESR2, and PTCH2 transcripts. By 50 DIM, the cows were included in a timed artificial insemination (TAI) protocol. Multiparous cows tended to have greater milk production (P < 0.08). Primiparous cows had a higher (P ≤ 0.05) relative abundance of IL6, PTCH2, and PGR mRNA. In contrast, Multiparous cows had a higher relative abundance of IL10 mRNA. All cows ovulated after the TAI protocol. The proportion of primiparous cows ovulating from calving to 50 DIM tended (P = 0.08) to be greater. Overall, the findings indicated that parity does not significantly affect energy metabolism and that multiparous cows have lower uterine inflammatory response associated with lower relative expression of IL6 and higher relative expression of IL10. These results led us to conclude that parity had little effect on puerperium, and according to the postpartum uterine condition, crossbred dairy cows can be considered healthy by 40 DIM.