EFFECT OF INCUBATION-TEMPERATURE ON THE GROSS PATHOLOGY OF TURKEY EMBRYOS

1. Turkey eggs were incubated at 36.5, 37.5 and 38.5-degrees-C. The age of mortality, the incidence of malpositions and the incidence of morphological abnormalities were recorded from all unhatched eggs. 2. Eggs incubated at 36.5-degrees-C hatched later than eggs incubated at 37.5-degrees-C but did not differ in age of mortality or incidence of malpositions and abnormalities. 3. Eggs incubated at 38.5-degrees-C hatched significantly less well than eggs incubated at 37.5-degrees-C and showed significant differences in time of embryo mortality. Overheated embryos had a mortality peak between 15 and 20 d of incubation and an increased mortality after 24 d of incubation. 4. Overheated eggs were characterised by a high incidence of embryos with head in small end, with excess albumen, ruptured yolk sacs, oedematous heads, eye cataracts and swollen down-plumules.