58 THE dairyman's MAKUAL. 



(figure 4), give an excellent idea of v/hat the typical form 

 of a dairy bull and cow should be. That of the Ayrshire 

 cow Flora (figure 3) is excellent, except in one respect, 

 viz., the rather short teats, which are common in this 

 breed. * 



The breeding periods of the cow occur at intervals of 

 twenty to twenty-one days, and usually begin at the age 

 of twelve to fourteen months; some Jersey calves (this 

 breed is naturally precocious) have bred at the age of 

 seven months or even earlier. Fleming, in his excellent 

 work on Veterinary Obstretrics, states that seventy -nine 

 per cent of cows are fertile and twenty-one per cent 

 sterile. My own observations certainly differ from this 

 author, for of twenty-eight herds, including my own, 

 with which I have been intimately acquainted, and in 

 which were altogether nearly 500 cows, there were but 

 three cases of absolute sterility. 



The cow carries its foetus about 280 days, or nine months; 

 the period of pregnancy, however, varies in cases from 

 240 to 301 days. Of 1,062 cases noted at a French agri- 

 cultural school 15 calved m 241 days ; 52 from 241 to 

 270 davs ; 119 from 271 to 280 days ; 544 from 271 to 300 

 days ; *^230 from 281 to 290 days ; 70 from 290 to 300 

 days ; 32 went beyond 301 days. The longest known 

 period is from 330 to 353 days. The averages given by 

 many observers are 283, 286, 2807,, 284, 282 for female 

 and 288 for male calves ; and all these coincide in the 

 belief that a male calf is carried several days longer than 

 a female. 



The cow rarely has multiple births ; but occasionally 

 twms, and even more, are produced. Twin births seem 

 to be hereditary, and it is believed by some prominent 

 veterinary practitioners that this peculiarity may easily 

 be made habitual by a course of selection in breeding. 

 Cases are cited in which the progeny of multiple bearing 

 cows have produced twins, and m one case seven calves 



