Our objective was to study the effects of housing conditions and the amount of boar contact in a protocol for estrus detection on estrus detection rate, timing of onset of estrus, duration of estrus, and timing of ovulation. After weaning, 130 multiparous sows were assigned to three treatments: HI, in which 52 sows were housed individually in crates and received a high amount of boar contact du...

This study was planned to determine the physical and chemical properties of cervical mucus collected during normal and induced estrus of Ossimi ewes. Estrus of 14 Ossimi ewes were induced by intravaginal sponges for 14 days. Estrus was observed one to two times in ewes after estrus induction with a range of 17-21 days. Cervical mucus samples were collected from all ewes (14 each for induced and...

The objectives of this study were to determine estrus behavior, interval to estrus, duration of estrus and time of ovulation of Boran, and Boran × Holstein Friesian (HF) breeds. A total of 113 cows and heifers from the two breeds were synchronized with two estrus synchronization protocols: 1) estradiol benzoate (EB) + controlled internal drug release (CIDR) + prostaglandin (PGF2α); and 2) gonad...

Based on studies of vaginal smears from wild-caught Swedish wood mice, females with three types of estrous cycles were identified: females with a continuous estrus; females with an estrous cycle between 6 and 11 days in length; and females that only rarely showed signs of estrus. We tested the pregnancy rates and how stable the estrus patterns were among the females. Ninety-one percent of the f...

Successful reproductive management in buffaloes depends on effective estrus detection. Urinary pheromones identified from natural estrous cycle have been reported to decipher estrus phase. However, its presence has not been analyzed in the urine after synchronization. Thus, our present investigation was to investigate the influence of synchronized estrus urine in bulls and to examine the presen...

This study determined whether the interval from estrus to ovulation was altered by giving P.G. 600 to sows at weaning. Mixed-parity sows received P.G. 600 i.m. (n = 72) or no treatment (n = 65) at weaning (d 0). Beginning on d 0, sows were observed for estrus twice daily. At the onset of estrus and thereafter, ultrasound was performed twice daily to determine the average size of the largest fol...

Cows exhibiting estrus near fixed-time artificial insemination (AI) had greater pregnancy success than cows not showing estrus. The objective of this study was to determine the relationship between follicle size and peak estradiol concentration between cows that did or did not exhibit estrus during a fixed-time AI protocol. Ovulation was synchronized in beef cows by applying the CO-Synch protoc...

Reproductive performance in cows following synchronization of estrus with intravaginal progesterone releasing devices (IVD) has varied with the length of treatment, cyclic status and prolonged return to estrus intervals in some cows following first AI. The objective of this study was to compare two methods of synchronizing and resynchronizing estrus on the reproductive performance of lactating ...

Recently, weak estrous behavior was assumed to be the cause of a decline in breeding efficiency in cattle. The present study investigated the effect of measuring the vaginal temperature on the detection of estrus in Japanese Black cows. First, the effect of hormone administration to cows with a functional corpus luteum on the vaginal temperature was evaluated by continuous measurement using a t...