Strategies to reduce embryonic mortality in buffalo cows.

The aim of the present study was to examine whether treatment with a GnRH agonist, hCG or P(4) on Day 25 after AI increased P(4) concentrations and reduced the incidence of embryonic mortality (EM) in pregnant buffaloes mated in mid-winter in a Mediterranean environment. The trial was carried out in two farms characterized, in previous years, by low (LEM Group), 153 buffaloes (DIM=150 +/- 7 days), and high (HEM Group), 284 buffaloes (DIM=163 +/- 5 days), incidence of embryo mortality. Animals were synchronized by Ovsynch-TAI Program and artificially inseminated. On day 25, pregnant buffaloes were randomly assigned to four groups: Control (no treatment), GnRH agonist (buserelin acetate, 12.6 mu g), hCG (1500 IU) and P(4) (341 mg of P4 i.m. every 4 days for three times). Progesterone (pg/ml) was determined in milk whey on Days 10, 20 and 25 after AI in all buffaloes and in Days 30 and 45 only in buffaloes pregnant on day 25 and assigned to four groups of treatment. Pregnancy diagnosis was undertaken on Day 45 by ultrasound. All treatments increased P(4) milk whey and reduced embryonic mortality in buffalo cows bred in the farm characterized by high EM.