Agricultural Research in New Hampshire 59 



mortality was too high to allow for significant comparisons. However, 

 the four or five chicks which survived the embryonic separation of the 

 yolk all showed presence of lesions. 



Comparative work with various dietary control measures has been 

 in progress for a year. The two specified rations commonly termed corn 

 base and oat base diets were fed to two groups of 30 mature breeding 

 females for an adjustment period of eight weeks, after which sixteen con- 

 secutive weekly hatches were made. Upon the completion of each hatch, 

 all pedigreed chicks were killed and their gizzards removed for study of 

 the presence and severity of lesions prevailing. 



Detailed reports are available covering each of these hatches, together 

 with a line graph showing the trend of average gizzard lesions severity 

 experienced in the two lots of chicks as produced. Throughout this 

 sixteen-week period the oat base diet was somewhat more protective 

 against gizzard lesion severity than was the corn base diet. Wide varia- 

 tions between hatches were noted, but in every case the chicks hatched 

 from those birds fed the oat base diet averaged to show a less severe lesion. 

 However, it remains doubtful if there is any significant difference between 

 the two lots. 



Tests were carried out supplementing various rations with 0.5 per 

 cent hesperidin, a flavanone glucoside. This supplementary product, as 

 a member of the citrin or vitamin P group of factors, was used to deter- 

 mine its possible action in strengthening gizzard capillaries and thus tends 

 to prevent the occurrence of hemorrhage lesions in day-old chicks. The 

 results indicated little or no effect in reducing the incidence or severity 

 of gizzard lesions. In place of hesperidin a 3 per cent dried cereal grass 

 was used. Again, there was no appreciable effect on the subsequent 

 gizzard score. (A. E. Tepper, E. F. Waller, C. W« Hess, T. B. Charles) 



The Etiology, Pathology, and Prevention 

 Of Contagious Indigestion 



Bluecomb disease as we encounter it is usually accompanied by one 

 of the three following histories: (1) affects young birds of both sexes 

 while they are still on the range, (2) affects only pullets in production 

 soon after they are confined to the laying house, (3) affects mature hens 

 throughout trie entire laying period. In this third group only an occa- 

 sional bird is affected every few days, and the disease does not reach 

 epidemic proportions. There has been some disagreement among poultry 

 pathologists as to whether the symptoms and lesions encountered in these 

 three conditions were all various manifestations of one disease or whether 

 they were different diseases. 



In our investigations we have worked primarily with the highly acute 

 fatal type affecting pullets soon after housing, and the results reported 

 here are those obtained with a virus isolated from such cases. On Sep- 

 tember 10, 1941, a poultry man submitted 3 dead and 2 sick hens to the 

 laboratory. Upon necropsy the dead birds all presented lesions grossly 

 typical of Bluecomb disease. Blood from the sickest of the two live birds 

 was drawn into a sodium citrate solution and was then injected into in- 

 cubating eggs. The hen was destroyed, necropsied, and tissues taken 



