Aravinda Ghosh, K NLeeba ChackoKAU2019-05-312019-05-312003172177http://krishikosh.egranth.ac.in/handle/1/5810105990PGWith the objective of studying the occurrence, onset, duration and intensity of metoestrual bleeding and its effect on fertility in natural and induced oestrus in cattle, detailed data of animals belonging to University Livestock Farm and those presented at Artificial Insemination Centre and Bull Station, attached to the Department of Animal Reproduction, College of Veterinary and Animal Sciences, Mannuthy, were collected using a suitable proforma. Animals with the history of metoestrual bleeding were randomly selected and allotted to the following groups. Group I consisted of 16 animals, comprising- of eight cows and eight heifers, with the history of metoestrual bleeding that were inseminated at natural oestrus. Sixteen animals in group II (eight cows and eight heifers) with the history of metoestrual bleeding were subjected to induction of oestrus on tenth day using 25 mg PGF2 alpha (Lutalyse), which were inseminated at 72 and 96 h after the administration of Lutalyse. Sixteen animals (eight cows and eight heifers) which did not show metoestrual bleeding formed the group Ill. Out of 1626 animals screened, 99 (6.09 per cent) animals exhibited signs of metoestrual bleeding in one or more oestrous cycles. The occurrence was found to be higher in heifers (9.87 per cent) than in cows (4.52 per cent). Higher percentage of Brown Swiss cross bred cattle (9.88 per cent) exhibited signs of metoestrual bleeding, followed by Holstein-Friesian cross bred (7.66 per cent) and Jersey cross breds (7.4 7 per cent). Out of 99 animals with metoestrual bleeding, eight (8.08 per cent) animals showed bleeding on the day of oestrus (day 0), 44 (44.44 per cent) on day 1 of oestrus, 26 (26.26 per cent) on day 2 of oestrus and 21 (21.21) on day 3 of oestrus. Duration of metoestrual bleeding ranged from 6-36 h with a mean of 13.38 ± 2.64 h. Thirteen (13.13 per cent), 57 (57.58 per cent) and 29 (29.30 per cent) animals exhibited scanty, moderate and profuse bleeding, respectively. Thick mucus blood tinged discharge was observed in 60 per cent of cases, which on microscopic examination revealed fern pattern, that lay scattered in disintegrated form with presence of RBCs, in stained smears. Thin mucus blood tinged discharge was noticed in 40 per cent of cases with presence of RBCs in stained smears, without fern pattern. Microbial growth was not detected when metoestrual discharge was inoculated on the culture media and incubated at 37°C for 24 h. Gram positive bacilli were detected as the contaminants after 48 h. Out of eight cows and eight heifers in group II subjected to PGF2alpha administration, seven (87.5 per cent) and eight (100 per cent) responded to treatment, respectively. The overall oestrus response was 93.75 per cent. The time taken for the induction of oestrus in cows was 66.14 ± 1.55 h as against 59.88 ± 1.66 h in group II heifers. Average duration of oestrus in cows and heifers was 25.13 ± 0.99 and 18.75 ± 0.53; 31.43 ± 1.13 and 28.75 ± 2.00, and 23.63 ± 2.27 and 19.38 ± 0.65 h for groups I, 11 and III, respectively. Analysis of data revealed significant difference in the duration of oestrus in cows and heifers in group II from that of cows and heifers in groups I and III (P37.5 per cent of cows and 12.5,37.5 and 50 per cent heifers showed high, medium and low intensity of oestrus, respectively. In group II the corresponding values were 57.14, 28.57 and 14.28 per cent in cows and 62.5, 25 and 12.5 per cent in heifers. In group III 12.5, 37.5 and 50 per cent cows and 25, 37.5 and 37.5 per cent heifers exhibited high, medium and low intensity of oestrus, respectively. Out . of eight cows and eight heifers induced, none exhibited metoestrual bleeding in the induced heat. The overall conception rate in groups I, Il and III were 18.75, 66.66 and 43.75 per cent, respectively. It can be recommended that induction of oestrus using prostaglandin can be employed for enhancing the conception rate in animals with the history of met oestrual bleeding.ennullThesis