Ovary response and embryonic mortality in buffaloes treated with GnRH or hCG

The aim of the present study was to examine whether treatment with a GnRH agonist or hCG in pregnant buffaloes on Day 25 after AI induce ovulation and increased P4 concentrations. The trial was carried out on 98 pluriparous buffaloes (DIM = 163 ± 75 days) diagnosed pregnant by ultrasound on day 25 after AI, and randomly assigned in two treatment groups GnRH (12 μg of Buserelin Acetate i.m) and hCG (1500 I.U. i.m.) after measurements of follicular diameter and evaluated ovulation. Milk samples were collected on Days 30 and 45 after AI, to assess P4 concentrations in whey. Differences between the follicular diameters of ovulation and P4 were tested by ANOVA. The incidences of animals which responded to the two treatments were analysed by Chi square test. The treatments on day 25 after AI induced ovulation respectively in 68.6% (GnRH) and 57.4% (hCG) of the buffaloes. No differences were found between diameter of follicle ovulated. Ovulation increased milk whey progesterone levels and reduced embryonic mortality in buffalo cows.