Temporal variation and risk factors associated with reproductive disorders in Hardhenu (Bos taurus x Bos indicus) dairy cattle

This study aimed to investigate the incidence and effect of non-genetic factors on reproductive disorders in the Hardhenu cattle population over a period of 11 years (2010-2021). The study included a total of 1340 cattle for calculating the incidence of reproductive disorders and analysed the occurrence of different reproductive disorders. In the present study, retention of placenta had highest frequency, accounting for approximately 18.36% of the incidence, followed by repeater cows (11.19%), metritis (6.27%), dystocia (0.60%), anestrus (0.45%) and prolapse (0.37%). Chi-square analysis revealed a significant relationship between the year and the incidence of reproductive disorders (p <.05). Logistic regression analysis of temporal variability of reproductive disorders was also analysed, with an increase in the odds from 2014 to 2020, peaking in 2017-2018 and 2018-2019. Logistic regression analysis showed that season and parity did not significantly influence the incidence of reproductive disorders. However, period of calving had a significant impact. Cows calving between 2008 and 2014 had a significantly lower odds ratio (0.13, 95% CI: 0.06-0.30), indicating a decreased risk, while those calving between 2014 and 2017 had a higher odds ratio (0.59, 95% CI: 0.38-0.90), suggesting an increased risk of reproductive disorders. Compared to parity 3, parity 1 (1.344, 95% CI: 0.869-2.08) and parity 2 (1.193, 95% CI: 0.768-1.851) showed highest odds ratio. Similarly, the odds ratio for winter (1.64, 95% CI: 0.93-2.89), summer (1.71, 95% CI: 0.89-3.26) and rainy season (1.64, 95% CI: 0.92-2.91) was higher as compared to autumn. The present results provided valuable insights into the incidence of various reproductive disorders and associated risk factors in Hardhenu cattle. These results can be utilized for targeted interventions to enhance reproductive health and overall productivity in dairy cattle.