Baixa fertilidade em touros no interior centro e sul de Portugal (Resultados de exames andrológicos em bovinos)

Abstract

Reproductive efficiency in cattle is important in the economic viability of farms. Currently, this efficiency is evident in determining the amount of aid to be received by producers. Between January 2012 and September 2015 were evaluated 223 breeding bulls through breeding soundness examination with ages between 13 and 156 months in 35 beef cattle farms in the center and south of Portugal. About 57% of the examinations were performed from September to December, due to higher demand for this service by producers, in order to prepare the time of mating. Bulls of breeds Limousin, Charolais, Alentejana, Mertolenga and their Crosses were evaluated and 72.6% were approved, 14.8% disapproved and recommended a reassessment to 12.6%. In sperm evaluation scope, for mass and individual motility, more than 50% of the sample sperm have a very good quality (grades 4 and 5 motility); 91% of reprobates have poor quality sperm. In 95% of approved bulls, body condition is adequate. And among those who failed, 15% had inadequate body condition. Considering age, 36% of approved bulls were less than 24 months old. Among the bulls that failed to be approved, only 6% were younger than 24 months and 56% were older than 5 years of age. Among the bulls qualified for revaluation (n=28), only 12 were reassessed and of these 50% was reclassified as approved. 21% of the bulls have low fertility and consequently an economic loss, and in this case, affecting up to 1,645 cows, which results in a € 770.000 potential loss.