A study on the pathogenesis of yolk retention in broiler chicks

Four different experiments were conducted to find out the effect on yolk absorption. In Experiment-1, yolk sac infection was introduced in half of chicks while remaining acted as negative control. In Experiment-2, one- third chicks were housed 24 hours after hatching, one third after 48 hours and remaining one third after 72 hours. In Experiment-3, one-third chicks were offered feed immediately after housing, one third after 24 hours and remaining one-third after 48 hours. Water was offered to all chicks immediately after housing. In Experiment-4, one-third chicks were fed with commercial starter ration, one third with, ground corn during first 24 hours followed by commercial starter ration and remaining one third were offered with 2% sugar solution in first 24 hours followed by, commercial starter rations. Body weight, yolk sac weight, yolk sac/body weight ratio, estimated yolk absorption and composition of yolk was studied for each group. Results of these experiments showed that yolk sac infection led to decrease in rate of yolk absorption. Moisture and protein percentage was increased in infected yolk but fat percentage was not affected by yolk sac infection. On the other hand, post hatch starvation due to delay in housing and delay in first feeding did not affect rate of yolk absorption. Moisture percentage was not affected while fat absorption increased and protein absorption decreased due to fasting. It was also observed that feeding ground corn in early life of chick led to slow absorption of yolk contents as compared to feeding commercial starter ration and 2 % sugar solution. Yolk composition was not affected by feeding commercial starter ration ground corn and 2 % sugar solution in early life of chick. It is concluded that experimental infection with E. coli and ground corn as initial feed leads to slow absorption of yolk sac in young broiler chicks.