Y4 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



generation of inbreeding. The effects of crossbreeding between dif- 

 ferent inbred families is also being studied extensively, and a stock 

 of normally bred guinea pigs has long been maintained as a control. 



The most certain effect of inbreeding has been found to be the 

 tendency toward uniformity within each inbred stock, with the result- 

 ing differentiation between different stocks. This differentiation can 

 not be put on a basis merely of high or low vigor. In a given family 

 vigor in one respect may be associated with lack of vigor in another. 

 It is, however, true that the inbred stocks have all shown a decline 

 from their original condition in most respects. An appreciable return 

 of vigor takes place on crossing different inbred lines. There are, 

 however, indications that the decline is not so much a necessary as 

 merely a likely result of inbreeding, as of any other rigid system of 

 mating. 



A series of papers has been prepared for the Journal of Heredity, 

 reviewing the present knowledge of inheritance of coat color in mam- 

 mals. 



BEEF CATTLE INVESTIGATIONS. 



BEEF PRODUCTION. 



The experimental cattle-feeding work in Mississippi, North Caro- 

 lina, and West Virginia, in cooperation with the State agricultural 

 colleges, was continued. 



At Canton, Miss., a duplicate of the previous years work was done 

 with three carload lots of steers. A comparison was made of cotton- 

 seed meal with silage as the sole roughage and in combination with 

 corn stover and oat straw. The results of the two years' work showed 

 no advantage in the addition of corn stover or oat straw to silage. 

 Twenty calves from the breeding herd were fattened for records on 

 cost of production. 



At Abbott, Miss., three lots of steers were fed, testing the efficiency 

 of cottonseed meal alone as compared with a combination of cotton- 

 seed meal and corn, the roughage for each lot being the same. This 

 was a duplication of the previous year's work. The results indicated 

 that cottonseed meal alone was the most economical ration. Two lots 

 of short-aged calves were fed to determine if it would be profitable to 

 finish them the following year, and also to compare the efficiency of 

 cottonseed meal alone and in combination with corn. The results 

 indicated that good profits could be made with such calves and that 

 cottonseed meal was the most economical ration. 



At Springdale, N. C, three lots of steers and one of calves were 

 fed in testing different methods of wintering. The cost of wintering 

 on pasture was $7 a head less than the common method of winter- 

 ing on ear corn and hay, and the cattle were in better condition in 

 the spring. The use of silage was also much more economical than 

 the common method. 



At Lewisburg, W. Va., three lots of yearling steers and three 

 lots of calves were wintered, testing the use of silage instead of 

 the common ration of hay and straw. Silage proved to be most 

 economical for both steers and calves. 



