Evaluación a la respuesta de un análogo sintético de la PG F2 alfa en un tabajo a tiempo corto de inseminación

Abstract

An anlog of PG F2 alpha was administered in 198 heifers (Holstein – friesian)  for lessen the interval of heat detection and working period of an A.I. programme.

The method "fixed time" insemination at 72 and 96 hours, after two inyections ot the drug, between eleven days interval, was not utilized. Cloprostenol 500 microgrammes per dose was inyected in all animals with vulnerable corpora lutea, according our criterion. Heifers showing not vulnerability at rectal palpation were inyected eleven days later. Standing heat "peaks" were founded 48 and 60 hours after administration of the drug in all cases, representing 60% of aII the heifers with visible oestrus. Silent ovulations were recorded.

The A.I. work was achieved in 13 days, and 81% of all animals were inseminated with a non return of 70% at 45 days over the initially 198 heifers.