PUBERTY IN HEIFERS AND PREMATURE LUTEOLYSIS IN THE FIRST ESTROUS CYCLE

Puberty is the beginning of the reproductive and productive process, and a gradual maturation process that begins during pregnancy and continues until the female reaches puberty. Corresponds to the first oestrus behavior signal heifer accompanied by development luteal phase of normal duration for the species. The 17β estradiol has been seen as the main regulator hormone onset of puberty. The luteolysis process occurs due to the secretion of prostaglandins F 2α by the endometrium in a pulsatile pattern, reaching CL through the venous-arterial local transportation counter-current system, which produces vasoconstriction and thus luteolysis. Usually this process takes place around the 17 th day of the estrous cycle, but if it occurs before the 16 th day, happens the phenomenon called premature luteolysis. In the premature luteolysis, interestros interval is shorter in animals, and is called short cycle, common in the first estrous cycle of the heifer after puberty.