AGRICULTURAL RESEARCH IN NEW HAMPSHIRE 59 



cent fat in 348 days. Another produced 10380 in 272 days, and the third 

 produced 7396 in 248 days. 



The practical significance of present results lies in the possibilities of 

 savings by reduced purchases of high protein concentrates without ma- 

 terial decline in production. 



As nutrition studies with lactating cows will involve at least two 

 complete lactations for each animal, publication of the results will be de- 

 ferred until tests with the second lactation period are completed. How- 

 ever, a manuscript on the growth phase, which was completed last year, 

 has been prepared for publication as a bulletin from this station. 



E. G. RiTZMAN, N. F. CoLovos, A. D. Littlehale 



The Effect of Vitamin A on the Utilization 

 Of Energy and Protein by Calves 



This study concerns the effect of vitamin A on the utilization of 

 energy and protein in the ration of young calves from birth to six months 

 of age. Three heifer calves were used, each of which was placed on a 

 vitamin A controlled intake practically from birth to six months of age. 

 One calf was receiving what is accepted as the normal requirement of 

 vitamin A in the form of cod liver oil, another five times the normal, and 

 the third one-twentieth of the normal, or practically a vitamin A deficient 

 ration. 



Three complete balances of energy and protein were obtained with 

 the calf fed the optimum amount of cod liver oil and three with the calf 

 receiving the deficient ration. Seventeen respiration experiments were 

 carried out periodically to determine the basal metabolism. Blood samples 

 were taken every two weeks from all three calves and analyzed for sugar, 

 calcium, and phosphorus. 



Calves receiving the optimum amounts of cod liver oil showed a high- 

 er percentage utilization of food than did the calf on the deficient ration. 

 The basal metabolism of the calf on the deficient ration was nearly 15 

 per cent higher than that of the other calves. Furthermore, this calf went 

 totally blind during the fifth month and high dosages of cod fiver oil 

 failed to restore sight. The blood analysis shows a low content of cal- 

 cium between the time milk feeding was stopped and the time the defi- 

 cient ration was fed. Utilization of energy from the ration was affected 

 long before any deficiency symptoms appeared. The basal metabolism 

 increased progressively as the deficient ration was fed. 



While this experiment is of a preliminary nature and with too few 

 calves, the findings warrant continuance with a larger number and with a 

 slight revision in the procedure. 



N. F. CoLovos, E. G. Ritzmax, H. A. Keener 



Nutritive Values of Fruits and Vegetables 



This project is concerned with a determination of the factors affect- 

 ing the nutritive values of New Hampshire grown fruits and vegetables 

 and is a phase of the national cooperative project entitled "Conservation 

 of Nutritive Value of Foods." This station's contribution to this national 



