Effects of Antibiotics Injected into Hatching Eggs on the Growth of Chickens

1. Two antiboitics were injected into the hatching eggs to study the effect to the hatchability and growth of chickens. 2. A minute hole was bored in the egg shell with a gimlet, and 0.2cc of the antibiotics, which was shown in Table 1, was injected into the egg through the hole. The eggs were then incubated to be hatched after sealing the hole with paraffin. 3. The chickens were kept-in cages up to the age of 150 days, and the increase in body-weight, food-intake and general condition of the chickens were surveyed. 4. Although the hafchability was low, the treated eggs showed the noticeable increase in body-weight uo to the age of 13 weeks (Tables 2 and 3). 5. In these chickens, no remarkable fluctuation of the number of erythrocytes was observed, while the increase of the number of leukocytes was observed after the age of 3 months. It was suggested that the latter phenomenon indicated increase of resistance to the diseases (Fig.1).