330 My\SS. EXPERIMENT STATION BULLETIN 247 



In the earlier experiments the rnaxiniuin amount of skim milk powder 

 (31 Vo ounces of the dry powder to 9 quarts of liquid) was fed daily until 

 the calves were four months old. 



During the past year calves have been reared on mucli smaller quanti- 

 ties of the powder, the object being to cut the cost. 



The procedure has been similar to that followed in our earlier work 

 except that when the calves were two months of age their daily allowance 

 of skim milk powder was cut to 21 ounces (6 quarts of liquid) and at 

 three months was again cut to 10y2 ounces (3 quarts of liquid), and u 

 special effort was made all through the experiment to induce the calves 

 to eat heartily of the dry grain mixture and rowen. 



Under present conditions dried skim milk fed as above suggested offers 

 the best substitute for liquid skim milk in the rearing of young calves. 

 Calf meals are fairly satisfactory but are apt to cause digestive disturbances 

 and do not promote as rnpid growth. 



The value of buttermilk powder for calves has lately been investigated. 

 It has produced gains at almost the same rate as did the skim milk powder 

 and rather more economically because of lower market price. Calves 

 do not consume it as readily at first as they do skim milk powder, and it 

 has a decided laxative effect in some cases. 



This work with skim milk substitutes was also reported in the August, 

 1928, issue of the Eastern States Co-operator entitled "Skim Milk the 

 Standard". The article was based on a talk given by Mr. Arcliibald during 

 the 1928 Farm and Home Week at M. A. C. Mimeographed copy of de- 

 tailed method of feeding furnished on reciuest. 



The Value of Calcium Phosphate in the Promotion of Growth and 

 Milk Production. (J. B. Lindsey and J. G. Archibald). This experiment 

 has been in progress for a number of years. The entire herd of cows was 

 fed a basic ration low in mineral matter, and to one-half of the herd 

 Hie mineral supplement consisted of especially prepared bone meal. The 

 results in the main were negative. The experiment was reported in the 

 Proceedings of the American Society for Animal Production. The sup- 

 plement during the last two years has been a mixture of 4 parts of dical- 

 cium phosphate and 1 part calcium carbonate. The accumulated data 

 from this experiment are now being studied and a final publication re- 

 viewing our work with bone meal, and giving in some detail the results 

 from the latter experiment will be ready for the press within a few months. 

 The indications are that the dicalcium phos])hate and calcium carbonate 

 were of some benefit but this is not at all marked. 



The Mineral Constituents of Forage Crops. (J. B. Lindsey and J. G. 

 Archibald). Because of the scarcity of data available showing the mineral 

 constituents of the ordinary roughage grown in Massachusetts, numerous 

 determinations of calcium and phosphorus have been made on botli the 

 roughage and grain fed in connection with our experiment on the need of 

 minerals by dairy animals. In addition, sixty-eight samples of hay and 

 silage were collected in different sections of the State, with the aid of the 

 county agents. The entire analytical work will be published as a part of 

 the publication on the mineral needs of dairy cattle. 



In general, it can be said that while individual samples varied widely 

 the data showed no pronounced deficit of mineral constituents. 



Mineral Requirements for the Growth of Dairy Heifers, (J. 6. Lindsey 

 and J. G. Archibald). Comparatively little information being available 



