| Popis: |
The effects of the age and the breed of chicks on the efficiency of the operation 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 different in the productivity and body constitution types. In the first experiment the operation of ovariotomy was carried out on the chicks of one of two lines of White Leghorn which were grown up to the age of 1-2, 3-4, 5-6 and 7-8 weeks; in the second experiment the same operation was carried out on the chicks of other lines and breeds at 4-6 weeks of age. Before the operation of ovariotomy chicks were starved for 12-18 hours with free access to water. During the operation 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 operation of ovariotomy was performed according to advanced protocol developed earlier by the author. Meanwhile, the curretage of the most caudal part of the ovary is not usually seen behind the oval of the left iliac vein, it 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, thereafter they were killed by the decapitation and autopsy was performed. It was found that the incidence of the full removal of the ovary significantly increases 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%) was achieved exclusively in layer breeds of chicken where the chicks have more delicate body constitution. At the maturity age operated chicks with small ovarian remnants were as sterile as the chicks with the full removal of the ovary; the percentage of sterile individuals in different breeds and ages varied from 61.5 to 100%. |
