378 EXPEBIMENT STATION KECOED. 



appliances, either designed or modified at the station, are described, including 

 trapnests, hoppers, catching hook and coop, blood can, fattening ci-ate. supply 

 can, egg cabinet, sorting tiible, marking system for eggs, and an electric egg 

 Candler. 



DAIRY FARMING— DAIRYING. 



The ration and age of calving as factors influencing the growth and dairy- 

 qualities of cows, C. H. EcKLEs (Missouri Sta. Bui. 135 (1915), pp. 3-91, figs. 

 27). — From replies to questions sent out by the Missouri Station to dairy cattle 

 breeders it appears that there is a wide range of opinion with reference to such 

 points as relation of age at first calving to type, milking qualities and size, and 

 the effect of heavy grain feeding during the period of growth upon size, milking 

 qualities, and type. With a view to securiug accurate data on these points, an 

 investigation covering eight years' time and including 40 animals was con- 

 ducted. 



The 40 animals were divided into two main groups, one of which received a 

 heavy ration from birth to first calving, the other group receiving a light ration. 

 After the first calving both received a normal ration for dairy cows. The 

 heavy ration consisted of whole milk during the first six mouths, and all the 

 grain and hay the animals would consume up to the first calving. The light- 

 fed group received skim milk during the first si.x months, and hay or pasture 

 only after this age up to the first calving. The factor of age at first calving 

 was introduced by having one-half of each of these two groups calve at an 

 early age for the breed and the other half about a year later. Complete records 

 of the feed received, growth as shown by monthly skeleton measurements and 

 weighing, were kept from birth to maturity. Milk records were kept for each 

 animal covering two or more lactation periods. 



The heavy ration resulted in a more rapid growth of skeleton, especially 

 during the period of most rapid development, but later the heavy ration 

 resulted in the animals becoming much fatter. The animals receiving the 

 light ration grew less rapidly, but growth continued longer, although this 

 group never reached quite the size of those having the heavier ration when 

 young. The difference between a heavy and light ration for growing heifers 

 showed more strongly upon the weight than upon the rate of skeleton growth. 

 It is suggested that one cause of small cows in commercial herds may be the 

 character of the ration during the growing period. 



It was found that age at first calving had a pronounced effect upon size of 

 cows. Milk production is a severe tax upon the cow and checks growth to a 

 marked degree, but gestation does not check the growth to any marked extent. 

 The strongest factor tending to stunt the size of cows is scanty feeding during 

 the growing period combined with early bre»Miing. The time of sexual ma- 

 turity of the animal is Influenced to a considerable extent by the ration. Those 

 receiving the heavy ration matured sexually at an age of from two to four 

 months younger than those receiving the light ration. 



The heifers receiving the heavy ration during growth were slightly Inferior 

 in milk production to those receiving the light ration. Apparently some detri- 

 mental effect upon the milking functions followed the use of the heavy grain 

 ration, but it Is not deemed probable that within the limits ordinarily found 

 under practical conditions Ihis factor would exert sufficient influence to be 

 worth consideration. Some high-producing cows were found in each group and 

 also some medium and some inferior. The data Indicate that the factors which 

 are the result of heredity, such as the influence of ^he sire and individuality 

 of the animal, are the real determining factors with reference to the milking 



