PROGESTERONE AND ESTRADIOL PROFILES DURING ESTROUS CYCLE AND GESTATION IN DWARF GOATS (CAPRA HIRCUS)

Serum progesterone and estradiol profiles during estrous cycle, gestation and parturition in four Dwarf goat females (Capra hircus) were monitored. Blood sampling was carried out daily during estrous cycle and on alternate days during gestation till parturition. Observations regarding length of estrous cycle, gestation length, litter size and birth weight of kids were recorded. With the initiation of cyclicity, estradiol attained higher levels (7.7 ± 1.7 pg/ml) at estrus phase and dropped down to the lower levels within 3 to 4 days post-estrus. Concomitantly, progesterone started to increase from the mean basal value of 0.1 ± 0.03 ng/ml on day-0 to 3.0 ± 0.9 ng/ml on day-6 of estrous cycle and reached the peak value of 7.7 ± 0.6 ng/ml on day-12. From day-15, a decline was observed in progesterone values till the end of the cycle. A second estradiol rise of 14.0 ± 1.2pg/ml was observed on day-18 of the cycle. The mean estrous cycle length was 18.2 ± 2.1 days. During gestation, higher progesterone levels were maintained in the range of 4.3–11.0 ng/ml. Estradiol remained at lower concentrations for 30-50 days of gestation, then gradually increased and reached 270 ± 13.0 pg/ml a few days before parturition. It dropped again to basal values within 1-2 days postpartum. The mean gestation length in Dwarf goats was 144.8 ± 3.9 days and the litter size was 1.8 ± 0.5. It was concluded that Dwarf goat is a prolific breed, having a short gestation length with multiple births being common

CHARACTERIZATION OF ENDOCRINE EVENTS AT OESTRUS IN DWARF GOAT (CAPRA HIRCUS)

This study was conducted to characterize the profiles of LH, estradiol and progesterone hormones during oestrus in Dwarf goats. Five does were synchronized into oestrus with 2 intramuscular injections of PGF2 at an interval of 10 days. Blood samples were drawn at 8 h intervals from 0 to 77 h after second injection and hormones were estimated by radioimmunoassay (RIA). One of the does did not show oestrus. In two goats, LH rises were observed from hours 25-45 and attained peak levels at h-70 after second PGF2 injection. In two other does the rise in LH was significantly earlier and reached peak levels at 24-30 h. The concentration of LH ranged between 7.5 and 30 ng/ml (mean 19 ng/ml). The estradiol peaks in does were noticed at the same time as that of the LH. Estradiol concentrations varied between 9 and 16 pg/ml (mean 12 pg/ml). The progesterone remained at basal levels (0.1-0.2 ng/ml) throughout the oestrus in all animals. These results indicate that the estradiol and LH rises have temporal relationship with each other, rising almost at the same time and LH fall was earlier than estradiol

REPRODUCTIVE EFFICIENCY AND PROGESTERONE PROFILE FROM PARTURITION TO PARTURITION IN DW ARF GOAT

A study was undertaken to look into the reproductive performance of female Dwarf goat. The serum progesterone profile was used to monitor various reproductive parameters including length of postpartum period, the resumption of cyclicity, gestation period, pre-partum period, parturition, litter size and kidding interval. Most of the animals conceived within 20-65 days of postpartum period. During gestation period, higher levels of progesterone were maintained with wide variations falling in the range of3-13 ng/ml. Notable feature was the fluctuation of progesterone level in the higher limits (> 3 ng/ml) throughout the gestation. However, a few days before parturition a decline was noticed in all the animals. This decline started at 6 + 0.4 days of prepartum and dropped to the lowest level of 0.1 ng/ml after the completion of parturition process. The length of gestation period was found to be 145.5+1.1 days. A very short kidding interval (204 + 19 days) and a big litter size was observed. All the parturitions were normal and a considerable weight gain (8.2 + 0.3 kg) was recorded during pregnancy. The initial birth weight of kids was 2.1 + 0.53 kg. All the animals of the lot conceived at first or second oestrous, indicating the high prolificacy of the breed