The reliability of a Korean black goat (Capra hircus coreanae) to detect estrus in Himalayan tahrs (Hemitragus jemlahicus) for an artificial breeding program was investigated. Estrus in six female Himalayan tahrs was synchronized using fluorogestone acetate (FGA) sponges. Thirteen days later, 200 IU of PMSG and 100 IU of hCG were injected before removing the sponges and simultaneously injecting 5 mg of PGF2alpha the next day. Penetration of the cervical canal and the thickness and location of red crayon marks were examined 40~43 h later. Two females treated with sponges containing 60 or 45 mg of FGA had estrogen levels of 8.7 and 11.1 pg/mL, respectively. No red marks were found on the backs of these two tahrs. The remaining females had higher levels of estradiol, and the red crayon marks were clearly shown. The cervical folds of these tahrs were readily penetrated and the insemination gun was smoothly inserted into the uterine body. In conclusion, a Korean domestic goat with its chest crayon-harnessed was successfully used to detect estrus of Himalayan tahrs. This technique might be utilized as a part of breeding programs for wild goats and avoid the need for a vasectomy of conspecific males.
Animals ; Breeding/methods ; Estradiol/blood ; Estrus/physiology ; Estrus Detection/*methods ; Estrus Synchronization/methods ; Female ; Goats/*physiology ; Male ; Progesterone/blood

To compare an injectable progesterone (MAD-4) with an intravaginal device (IPD), and natural O17 with synthetic oestradiol (OB) in a synchronisation protocol, 51 cows were divided into four groups. Each group was treated with one of the two sources of progesterone and one of the two oestradiol formulations. Oestrus behaviour, follicle diameter, and pregnancy rates were evaluated. Oestrus behaviour (p = 0.902), numbers of cows in oestrus (p = 0.917), follicle diameter (p = 0.416), and pregnancy rates (p = 0.873) were similar among the four groups. More cows in the group treated with the IPD and OB scored > 200 oestrus behaviour points compared to the other groups (p = 0.038). A longer interval between the end of treatment and oestrus was observed among cows treated with MAD-4 than cows given the IPD (p = 0.030), but no differences were found between animals receiving the two oestradiol formulations (OB and O17). While the use of MAD-4 requires further testing, similar responses to natural oestradiol observed in the present study could allow the use of this formulation in reproductive protocols because it is not associated with the potential human health risks of OB.
Administration, Intravaginal ; Animals ; Cattle ; Estradiol/administration & dosage/*analogs & derivatives/*pharmacology ; Estrus/drug effects ; Estrus Synchronization/*methods ; Female ; Injections, Subcutaneous/veterinary ; Ovarian Follicle/drug effects ; Postpartum Period/drug effects ; Pregnancy ; Pregnancy Rate ; Progesterone/administration & dosage/*pharmacology ; Reproduction/drug effects

This study was conducted to evaluate the influence of category (heifers, primiparous or multiparous cows) on pregnancy rates in a large scale resynchronization ovulation program. Nelore heifers (n = 903), primiparous lactating cows (n = 338) and multiparous lactating cows (n = 1,223) were synchronized using a conventional protocol of estradiol/P4-based fixed-time artificial insemination (FTAI). Thirty days after ultrasonography, females who failed the first FTAI were resynchronized with the same hormonal protocol prior to a second FTAI. The pregnancy status of each cohort was evaluated by ultrasonography 30 days after each FTAI. The average conception rate after the first FTAI and resynchronization was 80.5%. Heifers had a higher conception rate (85%) than primiparous (76%) or multiparous cows (78%; p = 0.0001). The conception rate after the first FTAI was similar among heifers (57%), primiparous cows (51%) and multiparous cows (56%; p = 0.193). After the second FTAI, heifers exhibited a higher conception rate (66%) than primiparous or multiparous cows (51%; p = 0.0001). These results demonstrate the feasibility of resynchronization in large beef herds for providing consistent pregnancy rates in a short period of time. We also demonstrated that ovulation resynchronization 30 days after FTAI is particularly effective for heifers, providing a conception rate of up to 66%.
Animals ; Brazil ; Cattle ; Estradiol/*pharmacology ; Estrus Synchronization ; Female ; Fertilization/*drug effects ; Insemination, Artificial/*veterinary ; Lactation ; *Parity ; Pregnancy ; Pregnancy Rate ; Progesterone/*pharmacology

Synchronization of estrus and ovulation are of paramount importance in modern livestock improvement programs. These methods are critical for assisted reproduction technologies, including artificial insemination and embryo transfer, that can increase productivity. In the current study, subcutaneous implants containing norgestomet were placed for long (14 days), medium (9 days), and short (5 days) periods of time in 70 crossbred ewes undergoing fixed-time artificial insemination. The resulting effects on estrus synchronization and conception rates were subsequently evaluated. Among the synchronized ewes, 85.7% (60/70) underwent estrus over a period of 72 h after progestagen treatment ceased. The shortest mean interval between withdrawal of the device and onset of estrus (34.2 +/- 8.9 h) was observed in the G14 days of P4 group (p < 0.05). The conception rate of the G14 days of P4 group was statistically higher than that of the other groups (83.3% vs. 60.9% vs. 47.8%; p < 0.05). In conclusion, 14 days of norgestomet treatment produced higher conception rates and a greater number of pregnancies at the beginning of the breeding season.
Animals ; Drug Implants/therapeutic use ; Estrus Synchronization/drug effects/*methods ; Female ; Fertilization/drug effects ; Insemination, Artificial/methods/*veterinary ; Pregnenediones/administration & dosage/*pharmacology ; Sheep

The objective of this study was to investigate factors that influence the success of resynchronization protocols for bovines with and without progesterone supplementation. Cow synchronized and not found pregnant were randomly assigned to two resynchronization protocols: ovsynch without progesterone (P4) supplementation (n = 66) or with exogenous P4 administered from Days 0 to 7 (n = 67). Progesterone levels were measured on Days 0 and 7 of these protocols as well as 4 and 5 days post-insemination. Progesterone supplementation raised the P4 levels on Day 7 (p < 0.05), but had no overall effect on resynchronization rates (RRs) or pregnancy per artificial insemination (P/AI). However, cows with Body Condition Score (BCS) > 3.5 had increased P/AI values while cows with BCS < 2.75 had decreased P/AI rates after P4 supplementation. Primiparous cows had higher P4 values on Day 7 than pluriparous animals (p = 0.04) and tended to have higher RRs (p = 0.06). Results of this study indicate that progesterone supplementation in resynchronization protocols has minimal effects on outcomes. Parity had an effect on the levels of circulating progesterone at initiation of the protocol, which in turn influenced the RR.
Animals ; Cattle/*physiology ; Dinoprost/administration & dosage/*pharmacology ; Estrus Synchronization/*drug effects/methods ; Female ; Fertility Agents/administration & dosage/pharmacology ; Gonadotropin-Releasing Hormone/administration & dosage/*pharmacology ; Insemination, Artificial/veterinary ; Ovulation/drug effects ; Pregnancy ; Progesterone/administration & dosage/*pharmacology ; Tromethamine/administration & dosage/*pharmacology

The present experiment aims to examine the efficiency of estrus synchronization using progesterone and equine chorionic gonadotrophin (eCG) and to look at luteal function. During the non-breeding and breeding season, 5 adult female Korean native goats were injected intramuscularly with 2.5 ml of physiological saline as the control. A progesterone impregnated intravaginal sponge was then kept in the same goats for 10 days followed, after a week, by an intramuscular injection of 500 IU eCG. Five adult female Nubian goats were mated with a fertile buck during the non-breeding season. During the non-breeding season 2 of the 5 goats showed a normal estrous cycle (ranging from 18 to 21 days) and 3 a short estrous cycle (ranging from 3 to 6 days). During the breeding season the equivalent figures were 1 and 2. The major axes of the corpus luteum (CL) were measured by means of calipers built into the ultrasonography system, and the concentrations of plasma progesterone (P(4)) were determined by double antibody radioimmunoassay. The mean major axes of the CL in goats showing the short cycle (6.1 +/- 0.5 mm) was significantly smaller than in those showing the normal cycle (8.9 +/- 0.5 mm; p < 0.01) and also the value of P4 in goats showing the short cycle (4.2 +/- 2.1 ng/ml) was significantly lower than for those showing the normal cycle (10.3 +/- 4.3 ng/ml; p < 0.05) at day 3 following ovulation. Three out of 5 Nubian goats became pregnant but only one goat carried to full term. The present experiment indicated that a combination of progesterone and eCG was effective in inducing estrus, although it resulted in a high incidence of short luteal lifespan. The low kidding rate and high incidence of embryonic loss may be due to the instability of the luteal lifespan.
Animals ; Chorionic Gonadotropin/*pharmacology ; Corpus Luteum/*drug effects/*physiology ; Estrus Synchronization/*drug effects/physiology ; Female ; Fertility/*drug effects ; Fertility Agents, Female/pharmacology ; Goats/*physiology ; Horses ; Pregnancy ; Progesterone/blood/*pharmacology

The use of artificial insemination (AI) in buffalo (Bubalus bubalis) is limited by poor ovarian activity during the hot season, seasonal qualitative patterns in semen, low resistance of sperm cells in the female tract, difficulties in estrus detection, and variable estrus duration. Although AI procedures are commonly used in bovine, use of AI has been limited in buffalo. In the zootechnical field, different studies have been conducted to develop techniques for improvement of fertilizing ability of buffalo spermatozoa after AI. In this study, for the first time, the use of alginate encapsulation and cryopreservation of buffalo spermatozoa is described, and the same procedure was performed with Holstein Friesian (Bos taurus) semen. Results obtained from in vitro analyses indicate that the encapsulation process does not have detrimental effects (compared to controls) on quality parameters (membrane integrity, progressive motility, path average velocity) in either species. Similarly, there were no detrimental effects after cryopreservation in either species. The fertilizing potential of encapsulated and cryopreserved semen was evaluated after AI in 25 buffalo and 113 bovine females. Pregnancy rates were not affected in either species. The results of this study show proof of concept for the use of frozen semen controlled-release devices in buffalo.
Buffaloes* ; Cryopreservation* ; Estrus ; Estrus Detection ; Female ; Humans ; In Vitro Techniques ; Insemination, Artificial ; Pregnancy Rate ; Seasons ; Semen ; Semen Preservation ; Spermatozoa* ; Water*

The objective of this experiment was to assess the relationship between electrical resistance of the vaginal mucosa and plasma progesterone for optimal mating time in the bitch. Eight mature beagle bitches were examined, and we observed eight times of estrus. Vaginal electric resistance was recorded weekly using a Draminski ovulation detector in anestrus, and daily in estrus. Plasma progesterone concentration was estimated by radioimmunoassay. In the bitch, incline in vaginal electric resistance (376.20 +/- 105.63 units) showed a closely association with the onset of proestrus. Ovulation day was determined as the first day when plasma progesterone concentration increased above 5.0 ng/ml (Day 0). On Day 0, vaginal mucous electric resistance was 438 +/- 132 units. Vaginal mucous electric resistance showed a slight decrease or was maintained until Day 0. However, it showed an explosive increase, and peaked on Day 1~3, which was above 600 units. Two of eight cases peaked on Day 1, three of eight cases were revealed on Day 2, and others were revealed on Day 3. After Day 4, resistance showed a rapid drop to below 600 units and reached 200 units on Day 8. The optimal mating time was determined when vaginal mucous electric resistance was above 600 units.
Anestrus ; Electric Impedance ; Estrus ; Female ; Mucous Membrane ; Ovulation ; Plasma ; Proestrus ; Progesterone ; Radioimmunoassay

OBJECTIVE: This study was to investigate the expression of CDK inhibitors, p27(kip1) and p57(kip2) in mouse endometrium during the estrus cycle and pregnant period. METHODS: Total RNA and protein were extracted from endometrium of mouse sacrificed at diestrus, proestrus, estrus, and metestrus cycle, and at day 1-6 post-coitum (p.c.), then semi-quantitative RT-PCR and western blotting of p27(kip1) and p57(kip2) was carried out. RESULTS: p27(kip1) and p57(kip2) mRNA was highly expressed in diestrus and proestrus stage than estrus and metestrus stage. In comparison with estrus cycle, p27(kip1) and p57(kip2) mRNA level was highly maintained in gestational endometrium (except p27(kip1) of day 5 p.c). p57(kip2) protein level was relatively low from day 1 p.c. to day 4 p.c. But it was significantly increased in day 5 p.c. and day 6 p.c. CONCLUSION: These results show that p27(kip1) and p57(kip2) may play a role in endometrial differentiation for regular estrus cycle and implantation, and especially p57(kip2) may play an essential role in endometrial differentiation for maintenance of implantation.
Animals ; Blotting, Western ; Diestrus ; Endometrium* ; Estrus ; Female ; Metestrus ; Mice* ; Proestrus ; RNA ; RNA, Messenger

OBJECTIVE: This study was to investigate the localization of CDK inhibitor, p57(kip2) in mouse endometrium during the estrus cycle and pre- and peri-implantation periods. METHODS: The p57(kip2) protein was immunostained from endometrium of mouse sacrificed at diestrus, proestrus, estrus, and metestrus cycle, and at day 1-6 post-coitum (p.c.). RESULTS: The staining in the luminal epithelium was very weak in comparison with glandular and stromal cells. In diestrus stage, immunoreactivity of p57(kip2) was heterogeneously strong in parts of decidualized or degenerated stromal cells. In proestrus stage, strong immunoreactivity p57(kip2) was largely found in stromal cells. But, p57(kip2) was showed low immunoreactivity in estrus stage. In metestrus stage, immunoreactivity of p57(kip2) was heterogeneously strong in decidualized stromal cells. In day 1-2 p.c., immunoreactivity of p57(kip2) was low in some endometrial stromal cells. In day 3-4 p.c., immunoreactivity of p57(kip2) was strong in some endometrial stromal cells. In day 5-6 p.c., immunoreactivity of p57(kip2) was strong in decidual cells. CONCLUSION: These suggest that p57(kip2) may play an essential role in endometrial differentiation for maintenance of implantation, especially decidualization of endometrial stromal cells.
Animals ; Diestrus ; Endometrium* ; Epithelium ; Estrus* ; Female ; Metestrus ; Mice* ; Phenobarbital ; Proestrus ; Stromal Cells