It, therefore, appeared if parentally-iminune chicks are vaccinated by 

 the wing-web method against Newcastle disease, no harm will be done, 

 but at the age of five weeks it is expected they will all be susceptible. While 

 if susceptible chicks are vaccinated at one day of age by the wing-web 

 method, it appears reasonable to expect a heavy mortality seven days later. 



W. R. DUNLOP 



Effect of Nitrophenide (Megasul) Drug When Fed at 

 Different Levels to Birds Through to Maturity 



At housing time each year there are often many stunted birds found 

 v\'hich must be culled out as undesirable. Upon autopsy a reasonable num- 

 ber of these birds present typical post-mortem findings of a thickened in- 

 testinal wall. The area chiefly involved is that commonly termed the duo- 

 denal loop and, to some extent, areas of the free portion of the small in- 

 testine. This condition is commonly called enteritis. Some investigators 

 have the opinion it is precipitated by a coccidiosis infestation. 



Many of these flocks have been fed on a prophylactic level of a coccidio- 

 static drug up to 12 weeks. From 12 weeks to maturity they do not have 

 the protection of such drugs- Therefore, on this project an effort has been 

 made to find out if feeding the drugs to birds through to maturity would 

 have a detrimental efifect on the general health of the bird. Furthermore, 

 it was necessary to determine if the feeding of drugs at various levels would 

 have any effect on the later resistence of the birds to coccidiosis infections. 



The drug which has been used so far has been nitrophenide (Megasul). 

 It has been used at two levels, 0.0125 percent and 0.01875 percent. Dupli- 

 cate groups of 110 birds each have been used at both levels along with 

 duplicate parallel groups on unmedicated feed. According to clinical ex- 

 amination and autopsy, no evidence could be shown where the drug had 

 toxic effect. 



Secondly, during the period of feeding, challenges of E. tenella and E. 

 nccafrix were made on random samples from the pens. Controls were run 

 and while they succumbed or lost weight the medicated, along with the 

 unmedicated, resisted infection by the challenge. Therefore, nitrophenide at 

 0.0125 level or 0.01875 percent level in the feed continued to maturity 

 does not interfere with build up of immunity to E. tcncUa or E. nccafrix 

 under controlled conditions. Furthermore, no evidence of toxicity could be 

 demonstrated in these birds when fed at these levels through to maturity. 



W. R. DUNLOP 



Abnormal (Bulging) Eye in New Hampshires 



The study of a peculiar bulging-eye condition in one line of the Experi- 

 ment Station New Hampshires is being continued. Associated with the 

 bulging, in adult birds, is an enlargement of the anterior chamber of the 

 eye, some impairment of vision, frequent shaking of the head, and in some 

 instances a pronounced curling upward of the outside toe. 



At hatching, distorted and seemingly enlarged pupils have been noted, 

 and at eight weeks of age definite bulging has been observed. The age at 

 which the abnormality manifests itself varies considerably among individ- 

 uals. 



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