Starvation 1 93 



B. Starvation 



Starvation exerts an influence parallel to that of acute 

 disease. In the young animal the development of the sex 

 functions is advanced or delayed according to the state of 

 nutrition. In highly fed, vigorous heifer calves, ovulation 

 and estrum may occur at six months, or even earlier. In 

 countries where cattle are reared in a semi-wild state, con- 

 stantly running at large where herbage is scanty, they 

 rarely ovulate until nearly two years old, so that, although 

 the bulls run in the herd, the heifers do not conceive until 

 well grown. The nutritive supply beyond the necessities of 

 the individual do not suffice for reproduction. In cattle 

 more highly domesticated, if they are underfed or otherwise 

 badly handled, ovulation or estrum frequently fails. I have 

 observed two-year-old heifers, badly kept, though not ex- 

 tremely poor, which failed to come in estrum because of 

 poverty, but bred promptly when the food supply was in- 

 creased. Semi-wild cattle generally conceive in early sum- 

 mer, at the time when grazing is at its best and the animal 

 has recovered its vigor after the privations of winter. The 

 same rule applies to cattle stabled in winter and grazed 

 during the summer. Animals which do not come in estrum 

 in the stable or, doing so, do not conceive, frequently breed 

 when increased vigor has been gained after grazing on 

 good pasture. 



A high state of nutrition does not necessarily accompany 

 an abundance of food. Any food may be so damaged that 

 its nutritive value may be lowered or destroyed, or, con- 

 taminated by various bacteria or fungi, it may become toxic. 

 Mere quantity of food, and even of technical nutritive ele- 

 ments in the food, does not mean good nutrition. I observed 

 a stable of cows and heifers whicfe were getting an abun- 

 dance of hay and grain of excellent quality, but all were un- 

 thrifty and emaciated. The non-pregnant animals did not 

 come in estrum. One cow could scarcely get up when down. 

 They were in charge of a lazy attendant, who gave them 

 plenty of food with fair regularity, but did not keep them 



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