Influenza del periodo, dell'età e della distanza del parto sull'anaestro primaverile della bufala

70 cow buffalo showed 325 total heats during the period from December to April. Buffoloes have been tested for studying the spring anaestrous without the influence of pre and post partum. The cyclic status was also studied after introduction in the herd of 3 bulls (on April 16). The 33.85% of heats observed revealed levels of milk progesterone lesser than 4 ng/ml (10 days after estrous). By the end of January the incidence of acyclic heats up to 56.76% of March-April. Spring anestrous occur independently of parturition and beginning of milk production. Data showed that spring anestrous is strictly dependent to the seasonal period, to the age of the animals as well as to the interval after parturition. The restoration of sexual promiscuity bring about the disappearance of acyclic status in the 40% and 50% of cow buffaloes after respectively 1 and 3 months showing the importance of the bull effect.