Data from two experiments were used to study the relationship between weaning-to-estrus interval (WEI, varying from 3 to 6 d) and the duration of estrus, the interval from onset of estrus to ovulation and fertilization results at 120 h after ovulation, in 201 multiparous sows. An increase in WEI resulted in a decrease in the duration of estrus (Duration of estrus (h) = [81 (exp1) or 88 (exp2)]-...

The objective of this study was to evaluate two protocols of estrous synchronization in non-lactating Toggenburg goats. Nineteen goats were allocated, according to body condition score and weight, into two groups (A and B) and evaluated utilizing two treatments (T1 and T2). Animals in the T1 and T2 groups received an intravaginal sponge (day 0) containing 60 mg medroxyprogesterone acetate for 6...

BACKGROUND Buffaloes are silent heat animals and lacunae in their estrus detection results a substantial economic loss in developing countries. Many advanced tools to aid heat detection have been developed but are neither affordable nor easily interpretable by marginal farmers. AIM The present investigation was made to develop a cost-effective estrus detection model by combining several known...

Dorsal hippocampal lesions in adult female rats leads to alteration in the estrus cycle with preponderance of estrus phase. The activity of the animals after the lesion increases, but it remains coupled with post lesion estrus cycle.

A study was conducted with 360 gilts and sows from four herds to determine whether fertility was affected when the final of multiple inseminations was performed in late estrus or metestrus (late insemination). Sows and gilts were inseminated at 24-h intervals immediately after the detection of estrus. After receiving a first insemination, females were paired according to parity and estrus statu...

Light-dark (LD) cyclicity contributes to a number of reproductive events in the rat, including estrus cyclicity, and the timing of parturition and postpartum estrus. Constant light (LL) disrupts the female's cyclicity, and fertility is typically diminished. To ascertain whether constant light similarly diminishes the fertility of postpartum females, LL and LD animals were compared over three su...

The objectives of this study were to evaluate estrus response and pregnancy rates resulting from timed artificial insemination (AI) following estrus synchronization using CIDR in postpartum beef cattle. A total of 100 cows were randomly divided into three groups. Groups 1, 2 and 3 were artificially inseminated at 48-50 h (n=30), 53-55 h (n=30) and 58-60 h (n=40) after CIDR removal, respectively...

In 117 weaned sows, changes in estrous behavior and vulvar reddening were related to timing of ovulation. Detection of estrus was performed every 8 h with four levels of boar stimuli to record the change in responsiveness to these stimuli. This resulted in four overlapping phases of estrus, during which a standing response could be evoked: 1) man estrus (standing response to a back pressure tes...

The beef cattle industry has seen rapid gains in economically desirable traits largely due to the selection and expanded use of genetically proven, superior sires made available through artificial insemination (AI). Recent surveys indicate, however less than 5% of the beef cows in the United States are bred by AI, and only half of the cattle producers who practice AI use any form of estrus sync...

Two experiments were conducted to evaluate an accelerometer system (Heatime; SCR Engineers Ltd., Netanya, Israel) to manage reproduction in lactating dairy cows. In experiment 1, lactating Holstein cows (n=112) were fitted with an accelerometer system and were treated with GnRH followed 7d later by PGF(2α) to synchronize estrus. A total of 89 cows that had a follicle >10mm in diameter and a fun...