SYNCHRONIZATION OF ESTRUM BY SINGLE AND DOUBLE DOSE OF PROSTAGLANDIN F2a IN CROSS BRED HEIFERS IN SUPEROVULATION PROTOCOLS

Abstract

Estrus was synchronized by the administration of 25 mg each of prostaglandin F2a (PGF2alpha) in 10 cross bred heifers in two doses at 12 days interval. Estrus symptoms and observation as per rectal palpation were recorded at each estrus following administration of each dose of PGF2a. The mean interval between treatment and appearance of estrus following administration of PGF 2alpha was 64.00 ± 10.22 and 52.8 ± 4.07 hours respectively. The percentage of reactors for the first and second dose of PGF2alpha was 60.00 and 100
percent respectively. The prostaglandins were effective in inducing luteolysis of previous cycles in 70.00% Vs 100.00% and the follicular development and CL formation following their ovulation was 60.00% Vs 90.00% and 50.00% Vs 100% in single and double injection groups respectively. Administration of prostaglandin in cattle in two divided doses with interval of 12 days rather than in a single dose, thus, helps in inducing earlier and more intense heat. Development of follicles and CL formation are found in a greater number of cases.