Читать книгу Bovine Reproduction - Группа авторов - Страница 148

The widely accepted minimum proportion of morphologically normal sperm is 70%. Below this threshold it is expected that fertility will be impaired and a bull cannot be classified as a satisfactory potential breeder. Generally, bulls that are at or near this threshold have at least two or three sperm defects; however, as a precaution, it is recommended that the proportion of sperm with nuclear defects or proximal droplets should not exceed 20% and the proportion with acrosome or midpiece abnormalities should not exceed 25%.