14 MASS. EXPERIMENT STATION BULLETIN 428 



DEPARTMENT OF ANIMAL HUSBANDRY 

 Victor A. Rice in Charge 



A Study of the Mineral Elements of Cow's Mill<. (J. G. Archibald and C. H. 

 Parsons.) The work with cobalt is still in progress. Extreme difficulties have 

 been encountered in developing a method sufficiently refined to determine the 

 very minute traces of this element present naturally in milk. All of the time 

 devoted to the project this year has been spent in trying out different methods 

 none of which have so far yielded reproducible results. 



Investigation of the Merits of Legume and Grass Silage for Massachusetts 

 Agriculture. (J. G. Archibald and C. H. Parsons.) A good grade of silage has 

 been produced this past year by mixing corn meal with various grasses at the 

 rate of 150 pounds of meal per ton of grass. The silage kept very well, had a 

 pleasing, mildly acid odor, and has been very palatable to cows. Considerable 

 differences have been noted in the suitability of different grasses for ensilage. 

 Reed's canary grass made only a fair quality of silage; bluegrass alone has not 

 been at all satisfactory; but bluegrass mixed with other grasses has made good 

 silage. In general, silage from a mixture of grasses or of grasses and legumes has 

 been more satisfactory than silage made from single species. 



Two technical articles based on this project have been accepted for publica- 

 tion during the past year. One, entitled "Seepage losses from a silo," appeared 

 in the Journal of Dairy Science, Vol. 28, No. 4, April, 1945, pages 321-324. The 

 other, entitled, "Studies in the chemistry of grass silage," will appear in the 

 Journal of Agricultural Research presumably within the next three or four months. 

 Conclusions of the first-mentioned article were that seepage losses in silage are 

 not as serious as losses from other causes, and with good management can be 

 reduced to a very insignificant figure. The most important conclusion in the 

 second paper was that variations in silage quality due to the kind of crop ensiled 

 were more significant than those due to the action of the preservative. 



In addition to this work on the formal project, some time has been devoted to 

 checking by observation and analysis the results obtained by a group of farmers 

 who ensiled surplus potatoes furnished to them by the War Food Administration. 

 In general a fair to good grade of silage was obtained, although a few failures 

 have been noted. 



Analyses of four lots of potato silage, one ensiled with alfalfa, two with oat hay, 

 and one with sweet corn fodder, show that these silages were higher in protein, 

 carbohydrate, and minerals than corn silage; lower in crude fat and fiber; and 

 much lower in carotene. This last is what would be expected, for potato tubers 

 do not contain carotene; and what little was found came from the relatively 

 small amount of roughage mixed with the potatoes when they were chopped. 



The quality of the silages made by mixing alfalfa or sweet corn fodder with the 

 potatoes was excellent; when oat hay was used, the quality was only fair the 

 rather high pH (4.9) indicating an unsatisfactory and insufficient fermentation. 

 More serious than any failure to obtain good silage, however, has been the damage 

 to cutter knives by stones mixed in with the potatoes during harvesting. 



The Effect of Feeding Synthetic Thyroprotein to Milking Cows. (J. G. Archi- 

 bald.) For a period of approximately seven months (April to November, 1944) 

 this project was conducted in the Holstein herd of the Medfield State Hospital. 

 Ten cows fed the hormone continuously for a period of twenty-one weeks, start- 

 ing about midway of their lactation periods, showed a definite response in milk 

 yield. In general this response took the form not of marked or sudden increase 

 in milk jield, but of greater persistency in milk flow than was to be expected 



