Thirty three subestrus buffalo cows and 10-normal cycling females with apparent estrus symptoms were allocated to one of four treatment groups. The lSt group (n=12) received 10 mg of PGF2α pervaginum. The 2nd group (n=10) injected with 10 mg of PGF2α at a depth of 1 cm on the labia majora. The 3rd group (n=ll) treated with 25 mg of PGF2 α injected intramuscularly. The 4th group (n=10) with apparent estrous signs received normal saline and used as control group. Plasma progesterone were estimated in all groups under investigation before treatment at (luteal phase), 1st and 2nd days following treatment and at 5th, 10th, 20th, and 30th after insemination. In all treated groups, the females confirmed in heat mated with good fertile buffalo bulls. Animals failed to exhibit standing estrus were artificially inseminated twice at fixed time (72 and 96 hours after injection of PGF2α). Pregnancy rates were determined by palpation per-rectum between 50 and 60 days following insemination (natural or artificial). The incidence of subestrus buffalo cows exhibited standing estrus was found to be higher after intravalvular and intramuscular injection of PGF2α (72.73-80.00%) than following administration of PGF2α pervaginum (58.33%). The time elapsed until appearance of heat symptoms not varied among all treated subestrus females. All treated animals exhibited standing estrus and 80% of the control group were ovulated. While the ovulation rate was recorded to be 60, 50 and 33.33% of buffalo cows that not exhibited standing estrus following administration of PGF2α pervaginum, intravulvar and intramuscular, respectively. The 1st service conception rate not varied among all subestrus females that exhibited standing estrus (50-62.50%) and control group (60%), while the total conception rate slightly increased in treated groups (75-87.50%), than the control one (70%). In buffalo cows that not exhibited standing estrus after treatment with PGF2α , The 1st service and total conception rates were observed to be 25 and 60%, respectively pervaginum, 50 and 50% intra-vulvar, respectively and 33.33 and 33.33% intramuscular. Low dose of intravulvar or intra-vaginal could be used successfully for improvement fertility of subestrus buffaloes. In addition the plasma progesterone concentration can be used for detection of silent estrus as well as pregnancy diagnosis and anovulatory cycle in buffaloes. |
