Vol. 9, Issue 11, Part F (2025)

Maternal factors, hereditary influences, uterine infections, genital tract abnormalities, hormonal imbalances, and several other variables contribute to the occurrence of repeat breeding (RB). Selection of an appropriate therapeutic strategy therefore depends on the underlying etiology. In the present study, RB animals were treated using four different estrus-synchronization protocols with timed artificial insemination (TAI): the CIDR-Ovsynch protocol, the Ovsynch protocol, the Double-PG protocol, and the G6G protocol. Animals diagnosed with clinical endometritis were allocated into two treatment groups. One group received an intrauterine suspension of cephalexin and serratiopeptidase combined with a single intramuscular dose of cloprostenol, while the second group was treated with the intrauterine suspension alone. Similarly, animals diagnosed with subclinical endometritis were divided into two groups: one group received a single dose of cloprostenol (75 µg/ml) following intrauterine saline lavage, whereas the other group underwent saline lavage alone.
The outcomes of the study show that the CIDR-Ovsynch protocol resulted in a significantly higher pregnancy rate (PR) of 70.96% (22/31) compared with the Ovsynch protocol, which achieved a PR of 45.71% (16/35) (t = 2.11, P=0.04). Among animals with delayed ovulation, the G6G protocol yielded the highest PR (65.62%; 21/32), followed closely by the Double-PG + GnRH protocol (62.16%; 23/37). However, this difference was not statistically significant (t = 0.29, P=0.77). In animals with clinical endometritis, treatment combining intrauterine cephalexin and serratiopeptidase with PGF₂α resulted in a higher PR of 46.66% (7/15) compared to treatment without PGF₂α (33.33%; 4/12), though this difference was not statistically significant (t = 0.84, P=0.41). Among animals with subclinical endometritis, the combination of saline lavage and PGF₂α produced a PR of 41.66% (5/12), which was higher than saline lavage alone (11.11%; 1/9), but again statistically non-significant (t = 1.55, P=0.14). In total, 183 animals were included in the study. These findings provide evidence-based guidance for veterinarians in selecting effective treatment strategies to enhance reproductive performance in repeat-breeding cattle and buffaloes.