Influence of Previous Vaccination Record of Breeding Stocks on The Efficacy of Fowl Pox Vaccine in their Day-Old Chicks

With the progress of mass raising of chicks, the wing-web-stab fowl pox vaccine has been applied more frequently than the feather-follicle vaccine. The stab vaccines have been used for the day-old broiler chicks, but recently the vaccines showed a bad take and poor immunity in some of broiler farms.The present research reported here was carried out to clarify the bad take phenomenon of the stab vaccine.Total 805 day-old male chicks of the Singlecomb White Leghorn were used in these investigations during 2 years from 1972 to 1973.Three vaccines used were: A (attenuated fowl pox virus, strain B.) and B (pigeon pox virus, strain Nakan-K III) by the stab method, and feather-follicle vaccine (pigeon pox virus, strain Nakano).The principal results obtained were as follows:When the breeding stocks were immunized by the feathe-follicle vaccine, the dayold chicks were given a good take by A and B stab vaccines.From the view point of good eruption formation in day-old chicks vaccinated percentage of take seemed to be lower in A stab vaccine than B when B stab vaccine had been applied for the breeding stocks. However, no difference of statistically significant was observed between A and B stab vaccines.On the other hand, when the breeding stocks were immunized by A stab vaccine, the day-old chicks were given a good take by B stab vaccine, and A stab vaccine showed apparently lower percentage of take than B.