1919] EXPERIMENT STATION RECORD. bll 



DAIRY FARMING— DAIRYING. 



Some factors influencing the rate of growth and the size of dairy heifers 

 at maturity, C. H. Ecki.es and \V. \V. Swett [MiMQuri stu. Research Hul. 

 31 (1918), pp. 8-56, pi. 1, figs. 15).— To serve as standards of growth tor Hol- 

 steins and Jerseys, data are published of the bod; weight ami height at wit, 

 by months of a group of heifers of each breed that wore kept under " normal " 

 conditions, that is, fed on skim milk from 2 weeks in 6 months oi age, With 

 alfalfa, silage, and a small amount of grain in winter, and good blue grass 

 pasture in summer. The plan was to keep the animals In h good thrifty condi- 

 tion hut not fat. The use of height at withers to measure skeletal growth :-■ 

 justified by computations showing that the percentage Increments in height at 

 hips, heart girth, and distance from shoulder point to pin bone in successive 

 ages maintain an approximately uniform ratio to the corresponding increments 

 in height at withers. As was expected, the ratios for hip width Increased with 

 age. 



The weights at birth and the mature heights of 30 HolsteU) and 32 Jersey 

 heifers are tabulated individually, the heights at intermediate ages being also 

 given for some of the animals. Little or no influence of birth weight on adult 

 height was discovered. 



Note is made of a Jersey heifer which at the age of 6 months was put on n 

 diet as low in calcium and phosphorus as could be secured from feeding stuffs 

 likely to be used in practice. The growth in weight and height was normal 

 for 13 months thereafter, when a physical breakdown ensued. 



The rest of this bulletin — the major part — is devoted to the presentation of 

 the complete results of a study, previously reported in its more practical as- 

 pects (E. S. R., 34, p. 378), of the influence of quantity of feed on the chan. - 

 in weight and height of dairy heifers from birth to maturity, and the effect or 

 early calving on their subsequent body development. The promised evidence 

 is produced for the previously expressed view that the check in growth of 

 young animals following parturition is a result of the physiological drain, not 

 of pregnancy, but of lactation. 



Dairy cattle breeding experiments (Hoard's Dairyman, 51 (1919 i, No. 11. 

 pp. 5U, 545, figs. S). — An outline is presented of a cattle breeding project 

 undertaken by the Dairy Division of the U. S. Department of Agriculture, which 

 involves experimental crosses between Jerseys and Holsteins and a study of 

 inbreeding and line breeding. This account was written by one of the editors 

 of Hoard's Dairyman after a visit to the Department's experimental farm at 

 Beltsvllle, Md. 



The feeding of concentrated food to dairy cows on pasture (Jour. lhl. A<ir. 

 [London], 25 (1918), No. 1, pp. 11-11).— This article reviews five experiments 

 conducted in recent years by various agencies l Armstrong Od Ho g n , Bo othc— fr 

 era Agricultural College, Leeds University, and the West of Scotland Agri- 

 cultural College), which provide information as to whether a decreased milk 

 yield was to be expected as a result of the adoption of the war time policy of 

 the British Board of Agriculture and Ministry of Food that milch cows on 

 pasture are not to be fed "cake" before the beginning of August. 



"It is rarely in agricultural experimental work that the results sbtalned in 

 different experiments carried out at such widely-scattered centers are so uni- 

 formly concordant as in the experiments dealt with above. They all agree in 

 Indicating that, so far as milk production is concerned, the feeding of con- 

 centrated food to milch cows on pasture is only required in the later half of 

 the season, say, from mid-July onwards. In the earlier half of the season, cows 

 receiving concentrated food gave no more milk than others that received none." 



