Comparative study of some characteristics of the semen of RR (rose comb) or rr (single comb) cockerels.

Comparative studies were made of semen samples from subfertile RR and normally fertile rr cockerels. These samples were obtained either by abdominal massage or directly from the tip of papillae. The numbers of collected sperm did not differ between genotypes and the sperm from RR cockerels were less motile than those from rr cockerels irrespective of the semen collection method. The uric acid concentration of seminal plasma was influenced by the semen collection method (massage greater than papillae) but no variations were induced by the genotypes. The ATP-ase and acid phosphatase activities found in the seminal plasma were influenced respectively by the genotype (rr greater than RR) and the semen collection method (papillae greater than massage). The fumarase and acrosin activities found in the sperm were not influenced by the semen collection methods while acrosin activity was found to be higher in RR than in rr cockerels. Correlations between these various characteristics are given in detail.