This study compared the responses shown by lactating dairy cows to four different P4-based protocols for AI at estrus. Cows with no estrous signs 96 h after progesterone intravaginal device (PRID) removal were subjected to fixed-time AI (FTAI), and their data were also included in the study. In Experiment I, follicular/luteal and endometrial dynamics were assessed every 12 h from the beginning ...

An accurate method of predicting the date of parturition in the bitch is clinically useful to minimize or prevent reproductive losses by timely intervention. Similarly, an accurate method of timing canine ovulation and gestation is critical for development of assisted reproductive technologies, e.g. estrous synchronization and embryo transfer. This review discusses present methods for accuratel...

and Implications To increase utilization of artificial insemination by beef producers, estrous and ovulation synchronization protocols must be re-evaluated in an attempt to reduce labor, cost, number of handlings, or a combination thereof without negatively impacting pregnancy rates. One potential way to reduce cost in these systems is through the strategic removal of hormones, such as the cont...

Introduction Bovine Viral Diarrhea (BVD) virus and Infectious Bovine Rhinotracheitis (IBR) virus are two of the major viral pathogens responsible for respiratory disease in cattle. These viral agents can be associated with pathology in the respiratory, immunologic, neurologic, hematologic, lymphatic, and reproductive organ systems (Grooms et al., 1998). Infections of cattle with BVD virus and/o...

A similar proportion of beef cows and heifers exposed to estrous synchronization (ES) and artificial insemination (AI) became pregnant during the breeding season, compared with females bred via natural service breeding. Females in a breeding system that included ES and AI calved earlier in the calving season, compared with females bred with natural service, but no advantage was present for weig...

Two experiments were performed to determine the effectiveness of different progestogens contained in intravaginal devices, different doses of eCG and subsequent hCG treatment on the reproductive performance of estrus-induced mature Lori ewes. In the first experiment, 88 ewes were allocated into two groups, and were treated with either fluorogestone acetate (FGA) sponges or Controlled Internal D...

Abstract The objective of this study was to evaluate the uterine microbiota composition cows on day 15 estrous cycle. Non-pregnant Bos taurus beef (n = 23) were exposed a pre-synchronization step followed by 7-d CO-Synch estrus synchronization protocol. On days -10, -3, 0 (exogenously induced ovulation), 7 and 14, transrectal ultrasonography performed ovarian structures, ensure synchrony, deter...

Five experiments were conducted on commercial farms in Brazil designed to develop the basis for an estrus synchronization protocol using melengestrol acetate (MGA) in Bos indicus cattle. These studies resulted in the development of the following protocol: 0.5 mg x d(-1) of MGA between d -14 and -1; 2.0 mg i.m. injection of estradiol cypionate on d -9; 48 h temporary weaning between d 0 and 2; a...