26 University of New Hampshire [Sta. Bui. 330 



The alfalfa tests have been carried on since 1937 with 35 strains 

 and numbered varieties of alfalfa seed, together with seven standard 

 varieties for checks. The data collected thus far show that of the 

 standard varieties Grimm, Ladak, Baltic, and Hardistan have stood 

 up very well. Several of the other strains have shown good results, 

 some surpassing the standard varieties in hardiness and yield. The 

 data collected have been forwarded to the United States Department 

 of Agriculture and will be combined with data taken from all alfalfa 

 nurseries in the country. 



The work on soybean testing was completed in 1940, and a sta- 

 tion circular will be published early in 1941. 



(Bankhead-J ones Offset Fund) 



ANIMAL HUSBANDRY 



Nutritional Studies with Dairy Cattle (E. G. Ritzman and N. F. 

 Colovos) 



The studies on the nutritional physiology of dairy cattle have 

 been continued. Between October, 1939 and May, 1940, twenty basal 

 metabolism experiments and twelve complete balances of ingo-outgo 

 of matter and energy were carried out on four Holstein heifers, the 

 animals being four months of age at the beginning of the experimental 

 period. During the period the animals were fed 7.23 pounds of di- 

 gestible nutrients daily, of which only 0.623 pounds was digestible 

 protein. On this ration the average daily gain in weight was two 

 pounds per head, or about 33 per cent higher than the generally ac- 

 cepted standard of 1.5 pounds per day for the first year. 



The basal metabolism of the 4-months old animals at the begin- 

 ning of the experiments was 20,470 calories per 500 kg weight. 

 Seven months later this had fallen to 12,015 calories, demonstrating 

 the extraordinary tissue stimulus that characterizes the rapid growth 

 at this early stage of life. 



Observations of the effect of visual light on basal metabolism 

 and other physiological activities have been continued. One pair of 

 the four animals was kept in darkened stalls for the seven months, 

 while the other pair was exposed to auxilliary illumination in addition 

 to natural daylight. Data on blood constituents showed no differ- 

 ence between the two pairs, nor was there an appreciable difference 

 in the basal metabolism. 



(Purnell Fund) 



Studies on the Energy Expended by a Horse at Work (E. G. Ritz- 

 man) 



A series of experiments have been carried out this year to study 

 the effects of drawing loads of varying resistance and at different 

 speeds on the energy expended by a horse performing the work. The 

 same apparatus which has been described in previous reports was 



