BlUn POX VACCIXKS AXI) llAriKUINS 



•ill 



and wattles witli virus IJ. I'ox nodules developed eijilit days later and reaelied 

 a inaxinuuii jirowth in an additional ten days. 



Lot -. Twenty-six days after vaeeination both birds were inoeulated on 

 eonil) and wattles with virus B. A mild ]U)x developed eif^ht days later, hut 

 soon disappeared without further develoi>nient. 



Lot o>. Forty-two days after vaeeination i)oth birds were inoculated on eonib 

 and watHes with virus B. I'ox was pronounced eijrht days later, one bird 

 showinti' dijihtheriiie patches in mouth as well i'.s pox. 



Control: two non-vaccinated liirds inoculated \\i(li \irus B. Incubation 

 period of eight days, maximum (k'vcloiunent four (l,i\,-, later. 



Part B. 



Two injections of a virus B vaccine were given a second grouj) of six birds 

 in the same maimer. The second injection was gi\en six days after the 

 first. Ihe grou]) was likewise divided into three lots of two birds each, and 

 inoculated with \irus B tiftcen, thirty, and forty-two days resj)ectively after 

 the second injection. 



Lot L Incuiiation i)eriod of ten davs, pox becoming pronounced five days 

 latei-. 



Lot 2. Slight pox de\elo]>ed in eight days in t)nly one bird, clearing up 

 within the next seven days. Second bird showed no evidence of the disease. 



Lot o. Pox developed in ten days, persisting for three weeks in a mild form. 



Control: two non-vaccinated, healthy birds inoculated with virus B. Pox 

 developed in eight days, reaching a maxinmm development four days later. 



Part C. 



Three injections of a virus B vaccine were given a third group of six birds 

 at intervals of six days. The group was again divided into three lots of two 

 birds each, and inoculated with virus B sixteen, thirty-one, and forty-two days 

 respectively after the third injection. 



Lot L Pox developed in eleven days and persisted in mild form. 



Lot 2. Pox developed in eiglit days and became pronounced in another 

 week. 



Lot o. Pox developed in twelve days and persisted in mild form for three 

 weeks. 



Control: two non-vaccinated, healthy birds inoculated with virus B. Pox 

 deve]oi)ed in eight days, reaching a maxinnun development three days later. 



Result. 



One, two, and three injections of the vaccine failed to produce an ab.solute 

 protection against artiHcial infection with homologous virus B. 



Experhnent 2. 

 Pari A. 



This experiment was similar to Experiment 1, excei)t that the vaccine was 

 nuide of virus C and the check inocidations were made with virus B. The 

 first group of six birds was given a 1 ec. injection of the vaccine, divided into 

 tliree lots of two birds each, and inoculated with virus B seventeen, twenty- 

 six, and forty days respectively after the vaccine injection. 



Lot 1. Pox developed nine days later, grew worse, and death followed in 

 one bird. 



Lot 2. Pox develoj)ed within eight days, but in weak form, and cleared up 

 in two weeks. 



Lot 3. Pox de\eloped within eight days in one bird and diiihtheritic roup 

 within ten days in the other. 



Control: two non-vaccinated, healthy birds inoculated with virus B. Pox 

 developed in nine days, reaching a maximum develo])ment four days later. 



