ANIMAL HUSBANDRY. II3 



the cost of feeding in relation to the actual increase of meat 

 secured made the feeding highly uneconomical. 



The proportion of carcase to live weight in these and other 

 animals has been related to certain external measurements made 

 on the live animals. In addition, the carcases were analysed 

 to find where the fat was being deposited, each butcher's joint 

 being analysed separately. From the figures so secured, im- 

 portant data have emerged. . In the first place tentative formulae 

 have been devised for ascertaining live-weight, dead-weight, 

 and percentage, from measurements of the longitudinal and cross 

 girths of the animal. From these formulae it may be possible 

 to ascertain, at any stage of fattening, the weight of the animal 

 and the percentage of carcase, without killing or weighing the 

 beast. Thus the condition of the animal for slaughter will be 

 indicated. Further, the figures will show the development of 

 the process of fattening, which of course has an important bearing 

 on the best time to kill. The figures have not yet been secured 

 for a sufficient number of beasts to justify a definite pronounce- 

 ment, but arrangements have been made with a large firm of 

 butchers in Cambridge under which the required information 

 is being obtained for all animals slaughtered there during the 

 present winter. 



Accurate data regarding the rate of growth and fattening 

 are of fundamental importance in estimating the relative economy 

 of various breeds, and of different systems of management and 

 feeding. Rather more than half the food that an animal eats is 

 used up simply in keeping the animal alive — for example, in 

 maintaining the heart-beat, in the periodic expansion and con- 

 traction of the lungs in breathing, in mastication and digestion,' 

 and in certain other vital functions which do not contribute to the 

 increase of weight which accompanies growth and fattening. 

 This continual requirement of food for maintenance forms a 

 constantly increasing overhead charge on the animal as long as 

 it is alive. The sooner the animal can be made ready for the 

 butcher, the smaller this charge will be. This is the fundamental 

 idea at the root of the Cambridge investigations on growth and 

 fattening. 



