Dominance rank, fear scores and reproduction in cockerels.

Cockerels were tested for dominance rank (509 tests) and sexual activity (79 tests). Fear responses to a human were estimated using a five-point scale (264 tests). The sexual activity of calm cockerels was 135.5 units, and that of fearful ones 66.6 units (P less than 0.05). There was a tendency to better fertility by cockerels from the first group (86.4% to 81.1%). In addition, eggs from this group showed improved hatchability compared with the fearful ones (88.5% to 77.6%). There was no clear relationship between dominance rank and fear score.

[Genetic polymorphism of poultry blood serum esterases in relation to resistance to bacterial infections]. / Geneticheskii polimorfizm ésteraz syvorotki krovi ptits v sviazi s rezistentnost'iu k bakterial'nym infektsiiam.

The experiments were carried out on White Leghorn, White Rock and Cornish chickens during the 1974--1975 season. The aim of the investigation was to study polymorphism of blood esterases in chickens in relation to their resistance to Salmonella pullorum and S. gallinarum. The data obtained indicate the following: 1) an additional, inheritant alyesterase fraction (A1) Appears in blood serum of resistant chickens after their contamination with Salmonella; 2) most chickens, which are resistant to Salmonella, have heterozygous genotype for blood serum cholinesterase.