Comparison of the Evaluation of Combination of Ultrasonography of the Reproductive Tract With Hormone Administration on Dairy Cow Fertility.

Further optimization of reproduction management programs in dairy cows is a contemporary research topic. In this context, our study aimed to compare a hormone program, named "uterus-ovary monitoring and classified use of hormone program" (M+C), with the Pre-OvSynch program. The M+C was based on regular application of B-mode ultrasonography during a voluntary waiting period to monitor the uterus and ovaries, while using various treatments under different conditions. Results of the 30-33-day and 60-day pregnancy/artificial insemination after the first AI of M+C were significantly better than the Pre-OvSynch ( p < 0.05). The pregnancy rates within 180 days in milk after M+C was significantly higher than that after Pre-OvSynch ( p < 0.05). The total number of inseminations used for M+C was significantly lower than that for Pre-OvSynch ( p < 0.01). The number of open days was fewer after M+C than after the Pre-OvSynch throughout the experimental period with highly significant differences ( p < 0.01). In summary, the use of M+C enhances reproductive benefits and reduces the need for hormone drugs among cows.
Competing Interests: BW was employed by Yangling Nongfu Agriculture and Animal Husbandry Technology Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
(Copyright © 2022 Wang, Xiao, Ma, Gao, Li, Jia, Jin and Lin.)