VENKATA NAIDU, G(MAJOR)SRINIVAS, MANDARaghunath, MAswani Kumar, KCHANDRA PRASAD, BORRA2021-07-242021-07-242020-10https://krishikosh.egranth.ac.in/handle/1/5810170821THESESTreatment of sub-estrus and true anoestrous high yielding lactating graded Murrah buffaloes (Bubalus bubalis) using estrus and ovulation hormonal protocols, Double PGF2α, Presynch-Ovsynch, Ovsynch and CIDR Ovsynch their influence on fertility in farm and field during breeding and low breeding season was studied. The estrus response following hormonal treatment was 91.30, 85.71, 91.66 and 92.85 per cent in DPG, POVS, OVS and COVS in farm where as in field it was 85.66, 80.43, 80.95, and 86.84, respectively. The onset of estrus (hrs) following hormonal treatment was 52.0, 50.31, 51.31 and 48.20 in DPG, POVS, OVS and COVS, respectively in farm and 50.12, 51.63, 53.52 and 50.31 in DPG, POVS, OVS and COVS, respectively in field. Peak estrus synchrony with incidence of estrus (63.63 to 81.81%) between 48 to 72 hours following the treatment in all the groups was observed both under farm and field conditions. Pre ovulatory follicle (POF) diameter (mm) observed at the time of AI in DPG, POVS, OVS, COVS and control group buffaloes were 12.86, 14.15, 13.16, 11.58, 11.15 and 11.45, 12.47, 11.75, 10.11, 10.15 in pregnant and non-pregnant buffaloes, respectively under farm conditions and 12.44, 14.21, 13.05, 11.32 and 11.65; 11.22, 11.31, 10.92, 9.49 and 9.35 in pregnant and non-pregnant buffaloes, respectively under field conditions. Ovulatory response (%) observed on day 10 post AI in DPG, POVS, OVS, COVS and control group buffaloes were 56.21, 78.57, 75.00, 64.28 and 56.25, respectively in farm, while the same in field was 50.00, 65.21, 61.90, 47.36 and 37.77, respectively. The mean diameter (mm) of the corpus luteum (CL) was recorded on day 10 post AI in order to study the relationship of CL with pregnancy status in treated and control buffaloes. The conception rate in relation to CL diameter (mm) was highest in POVS (17.15 Vs 64.28%) followed with OVS (16.16 Vs 58.33%), COVS (15.97 Vs 50.00%), DPG (15.95 Vs 50.00%) and control (14.65 Vs 43.75%) groups, respectively in farm, while the conception rate with that of CL diameter (mm) in field was highest in POVS (16.65 Vs 54.34%) followed with DPG (15.55 Vs 46.50%), OVS (15.05 Vs 50.00%), COVS (14.75 Vs 36.84%) and control (14.15 Vs 28.88%) groups, respectively. The per cent conception rate at induced/observed estrus were 39.13, 42.85, 41.66, 28.57 and 25.00 in DPG, POVS, OVS, COVS and control group, respectively in farm conditions, while per cent second service conception rate was 8.69, 14.28, 16.66 , 14.28 and 12.50, respectively, whereas per cent third service conception rate was 2.1, 7.14, 00.00, 7.14 and 6.25, respectively. The per cent conception rate at induced/observed estrus were 32.16, 32.60, 33.33, 23.68 and 15.55 in DPG, POVS, OVS, COVS and control group, respectively in field conditions, while per cent second service conception rate was 11.18, 15.21, 11.90, 10.52 and 8.88 respectively, whereas per cent third service conception rate was 3.14, 6.52, 4.76, 2.63 and 4.44, respectively. In the present study no significant difference was observed in serum total cholesterol concentration, mean hemoglobin (gm/dl) level and Mean PCV (%) between days of the treatment with DPG, POVS, OVS, COVS and control groups protocols in farm and field and during seasons also. The mean levels of serum progesterone recorded on different days of treatment day -10, 0, 11, day of A.I and day 21 post AI in postpartum sub estrus buffaloes during breeding and high breeding seasons in farm and field. The difference between BCS groups in farm and field were significant in POVS and OVS treated groups. Higher conception rate was recorded in buffaloes belonging to L2 group (parity) treated with POVS in both farm and field condition. In farm, higher conception rate was recorded in postpartum sub-estrus buffaloes belonging to L2 group treated with DPG during breeding and low breeding season, whereas in field higher conception rate was recorded in L2 group during breeding and L3 group during low breeding season. In the present study the conception rate varied between T1, T2, and T3 (service period) groups. Maximum conception rate was recorded in postpartum true anoestrous buffaloes subjected to OVS protocol in T2 group both at farm and field condition. While in COVS group maximum conception rate was recorded in T2 group both at farm and field condition. Maximum conception rate was observed in T2 and T3 group at farm and T2 in field level in control group. In the present study cost per pregnancy was recorded as Rs-/ 660, 1719, 1346 and 3271 in farm and 710, 2033, 1570 and 3271 in field treated with DPG, POVS, OVS and COVS respectively. It is concluded that estrus and fertility response in postpartum lactating anEnglishThesis