The selection of cocks for reproduction by comb development has been employed usually in the aviculture; however, studies have been necessary to establish the efficiency of this method of selection. The objective of this paper was to compare the seminal characteristics in cocks selected to reproduction by comb development. Sixty-five broiler breeder males (AgRoss strain) were selected to breed at 20th week old and divided in two groups, A: birds without comb (n=33) and B: birds with comb (n=32). To evaluate seminal characteristics, semen was collected weekly between 24 to 71 weeks of age. Group means were compared by the Student's t and Wilcoxon tests while profile analysis were performed for to verify effects of group, age, and group x age. Seminal volume, sperm concentration, motility and vigor were greater (p < 0.01) for group B from 24-31 weeks of age. Percentage of sperm morphological defects was greater in group A during 24-27 (p < 0.01) and 32-35 (p < 0.05) weeks of age. Mean body weight was higher for group B between 24-39 weeks of age (p < 0.05) and for group A between 60-71 weeks of age. There were no main effects of group for seminal characteristics or body weight (p > 0.05), but effects of age (p < 0.001) and group x age interaction were significant (p < 0.05), except for vigor (p > 0.05). Low or no correlations were observed between seminal characteristics and body weight. In conclusion, the method to select cocks by observation of comb development at 20 weeks of age showed efficient.
Cocks; Reproduction; Male; Comb; Semen
