SADASIVA RAO, K(MAJOR)SESHAGIRI RAO, ARAGHAVENDER, K.B.PMUNEER AHMAD ANSARI, SHAIK2018-10-052018-10-052007-03http://krishikosh.egranth.ac.in/handle/1/5810074823ABSTRACT : Studies on postpartum anestrum with special emphasis on induction of estrous in cross bred cows were undertaken at Military dairy farm, Bowenpally, Hyderabad. A total of 676 crossbred cows were studied to investigate the reproductive disorders and the incidence of smooth ovaries, post service anestrum, postpartum anestrum, silent ovulations, anovulatory heat, luteal persistency, luteal cysts, follicular cysts and repeat breeder were found to be 8.88, 6.66, 13.31, 2.66, 3.25, 4.88, 4.44, 3.25 and 21.30 per cent, respectively. The incidence of postpartum anestrum was found to be 13.31 per cent among cross bred cows, as per the data available at Military Dairy Farm, Bowenpally, Hyderabad during the period 2001-02 to 2005-06. The body condition score of the 80 postpartum anestrus crossbred cows selected for different treatment groups was evaluated and found to be more number (66) of cows were in the range of 3.0-3.5 body condition score. The mean values of serum calcium (9.73 ± 0.30 mg%), serum phosphorus (6.20 ± 0.25 mg%), serum cholesterol (94.35 ± 6.44 mg%) and serum glucose (52.25 ± 3.25 mg%) were found to be significantly lower in postpartum anestrus cows than the mean values of serum calcium (14.53 ± 0.38 mg%), serum phosphorus (7.88 ± 0.20 mg%), serum cholesterol (140.58 ± 8.68 mg%) and serum glucose (70.25 ± 2.31mg%) in cycling cross bred cows. Among 80 postpartum anestrus crossbred cows treated with various treatment protocols, the estrus response was found to be 100 per cent in all the three treatment groups and 90 per cent in control group. The days taken for the onset of estrus in PMSG (59.3 ± 1.76 days) group was found to be shorter than in GnRH-PGF2α -GnRH (69.05 ± 1.67 days), in PMSG (68.1 ± 2.46 days) and in control (79.55 ± 2.47 days) groups. The percentage of occurrence of estrus was found to be higher (80 per cent) during night time than during day time. The intensity of induced estrus was observed to be better in PMSG and PMSG + hCG groups than in GnRH-PGF2α-GnRH and in control groups. The intense estrus symptoms were observed to be 0, 70, 60 and 11.11 per cent in GnRH-PGF2α-GnRH PMSG, PMSG + hCG and control groups, respectively. The duration of estrus was found to be significantly longer (45.80 hrs) in cows treated with PMSG group. Similarly, the interval between treatment and onset of estrus was observed to be significantly earlier (2.75 days) in PMSG group, than in GnRH-PGF2α-GnRH (7.00 days) group, in PMSG + hCG (3.90 days) group and in control (16.45 days ) group. The first service conception rate and overall conception rate were observed to be better in GnRH-PGF2α-GnRH (60 and 90 per cent, respectively) group than in PMSG (30 and 70 per cent, respectively) and in PMSG + hCG (40 and 80 per cent, respectively) groups. Similarly, service per conception was also observed to be better in GnRH-PGF2α-GnRH (1.44) group than in PMSG (1.71), PMSG + hCG (1.75) and control (1.66) groups. The service period was observed to be longer in GnRH-PGF2α-GnRH (81.33 days) group than in PMSG (70.5 days), in PMSG + hCG (73.37 days) and in control (69.50 days) groups.ennullThesis