AGRICULTURAL RESEARCH IN NEW HAMPSHIRE 51 



of the entire alimentary tract determined. The gizzard contents were 

 preserved for further analysis. 



The fecal samples collected have been air-dried, ground, and analyzed 

 for total nitrogen. There is no marked difference between the total nitro- 

 gen content of these feces and those of the previous experiment in which 

 birds received animal protein in their diet. However, there were differ- 

 ences in growth, as reported by cooperators of the poultry department. 



Uric acid nitrogen content of the feces samples obtained from the 

 animal protein experiment previously reported have been determined. No 

 definite conclusions on the differences between groups can be made. The 

 variance between birds within a group is as much as between average 

 values of groups. Further nitrogen studies on these feces will be con- 

 ducted in order to determine reasons for variations between birds within 

 a group. Similar analyses will be made on the feces samples collected in 

 the vegetable protein experiment described above. 



In order to get a more uniform basis for the uric acid comparison, the 

 data found were reorganized by calculating the per cent uric acid nitro- 

 gen on the basis of the nitrogen consumed. The results show an apparent 

 rev^ersal of action between the 15 per cent and the 19 per cent levels of the 

 two protein sources; i.e., fish meal and dried skim milk. Work on the 

 enzyme action of the dried gizzard is continuing. 



No new^ feeding trial is contemplated for this year. Analytical work 

 on the fecal samples collected will be continued, and the data of three 

 feeding experiments will be correlated. 



R. C. RiNGROSE, T. B. Charles, S. R. Shimer, H. A. Davis 



The Cause and Prevention of Gizzard Lesions in Chickens 



Current progress on this study is focused on the possible role of in- 

 heritance and comparative work with various dietary control measures. 



Chicks hatched from the third generation of groups giving high and 

 low incidence of lesions follow ed the same trend as the previous genera- 

 tion. The high group was consistently high with an average gizzard score 

 of 1.57 for 173 chicks. Greatest change occurred in the low group where 

 the score for 168 chicks declined to 0.78 from a previous average of 0.91 

 for the second generation. The fourth generation of pedigree chicks is 

 now being raised. 



The eff'ect of diet upon the cause and prevention of the condition 

 has been studied by using a standard diet to which various supplements 

 are added. All chicks were killed at four weeks of age and the gizzard 

 scored for the occurrence of lesions. There is evidence that cod liver oil 

 increases the occurrence of the condition. The reported preventive 

 action of cholic acid has been tested and confirmed. 



The previous annual report suggested the use of the Beckmann spec- 

 trophotometer to determine the enzyme activity of the gizzard, accord- 

 ing to a method previously mentioned. Work during the past year has 

 shown that the Klett-Sum'merson photoelectric colorimeter may be used 

 to good advantage with this method. There are definite indications that 

 it w^ll be possibfe to develop this method to a practical point of opera- 

 tion, so that comparisons between enzymatic activity of gizzards can be 



