Age and breed influence on the efficiency of ovariotomy in chickens
The influence of the age and the breed of chicks on the efficiency of ovariotomy were studied. The experiments were carried out on female chicks of two lines of the breed White Leghorn and also on 7 other breeds. all different in the productivity and body constitution types. During the surgery manipulation chicks were fixed on the special tables, and as the main surgical tools- ophthalmic scissors and tweezers with straight and curved brunches were used. Muscle relaxant rometar was used for the immobilization of the chicks. The abdominal space was penetrated through the last intercostal space on the left. The ovariotomy was performed according to advanced protocol developed earlier by the author. The process of curetage of the very caudal part of the ovary, (usually it isn’t seen because the oval of the left iliac vein), was carried out at first, in the direction from the tail to the head; then the curretage of the other parts of the ovary was carried out, observing the direction from the head to the tail. Survived after the operation chicks were grown up to the age of 20-25 weeks, further they were killed by the decapitation and autopsy was performed. It was found that the incidence of survival after the full removals of the ovary significantly increase from 1-2 weeks of age to 5-6 weeks and then tends to decline to 7-8 weeks of age. The highest efficiency of the operation (over 60.0 % of the full removals of the ovary) was achieved exclusively in layer breeds of chicken where the chicks have more delicate body constitution at 4-6 weeks of age.