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VARIATION in weight of tissues which respond to hormone stimulation may arise from: (1) variation prior to hormone stimulation, (2) variation in amount of hormone to which the tissue is exposed, and (3) variation in sensitivity of tissues of different individuals. Both initial variation and that due to hormone stimulation are affected by genetical and environmental differences between individuals. This report is concerned with early identification of genetic effects on the weight responses of the testes and the comb. These may, or may not, characterize the responses expected from each chicken throughout its life span. The small amounts of androgen or gonadotrophin which may be present in the blood stream prior to 11 days after hatching would appear to be below the threshold for stimulation of comb and testis size in large bodied breeds. Although Breneman (1941) obtained evidence of gonadotropic and androgenic effects on the testes and combs of …

IT WOULD be of considerable advantage if a substance could be found which would minimize the deterioration of the interior quality of eggs yet add sufficient strength to the shells to reduce the probability of cracking. The most effective method of maintaining albumen quality of eggs is by coating the shell with a film of some mineral oil such as liquid paraffin, Romanoff and Yushok (1948). The oil film adds nothing to the strength of the shell, Tyler (1961) personal communication, and it takes a considerable time to dry. Yushok and Romanoff (1949), Grotts et al. (1957), have coated egg shells with various plastics attempting to obtain continuous films which would be highly impermeable to carbon dioxide and water vapour and so preserve albumen quality. This approach has been extended in the present work by using several different polymers and examining a number of those already tested in more detail.…

INTRODUCTION MANY workers have shown the effectiveness of oiling eggs in maintaining albumen quality and reducing the weight loss. Recently interest has centred upon the various methods of applying the oil and the best time at which it should be applied (Schwall et al., 1961; and Goodwin et al., 1962). Mueller (1958) showed that the loss of CO2 was independent of the loss of water from the egg. However, he later (1959) studied the other factors which affect the loss of albumen quality and found that the initial albumen quality and the movement of water from albumen to yolk were the most important factors whereas the effect of the loss of CO2 was surprisingly low. Korslund et al. (1956) and Vondell (1961) have shown that the relative humidity of the storage room does not affect albumen quality loss. Following the study of synthetic polymers and alginates for coating eggs and…