Puberal Characteristics and Early Growth of Charolais Bulls on High Nutrient Allowance

Twenty-seven Charolais weanling purebred bulls, fed concentrate ad libitum, were used to study puberal characteristics and early growth. Three calves were removed from the experiment for inability to protrude the penis and serve the artificial vagina.For the 24 bulls the average age at collection with artificial vagina of the first sperm and first motile sperm was 38 ± 1 and 39 ± 1 weeks, respectively. The first ejaculate meeting the minimum puberal criteria was obtained at a mean age of 41 ± 1 weeks. Body weight at puberty averaged 400 ± 13 kilograms. The ranges in age and body weight were 33 to 53 weeks and 266 to 499 kilograms. Semen characteristics and freezability of the first ejaculate were highly variable. First ejaculates for seven of the 24 bulls, however, satisfactorily withstood freezing and 3 weeks of storage in liquid nitrogen.Body weight at 365 days of age averaged 520 ± 10 kg (range 430 to 615 kg).