The Assemblitig of Herds 691 



ciency sells only inferior females, while the owner of an effi- 

 cient herd must find a market for superior animals. In a 

 healthy herd the limit for profitably holding cows and heifers 

 is quickly reached, since ideally the female herd increases 

 by one half its number of females of breeding age each year. 

 That is, a herd of one hundred cows should ideally produce 

 fifty heifer calves, and the second year another fifty. Since 

 in the third year the first fifty heifer calves are in breeding, 

 there should be born seventy-five female calves, and the next 

 year one hundred. The progress in numbers goes on with 

 increasing momentum. The actually successful breeder must 

 quickly find a market for his females, and must sell those of 

 good, as well as of poor quality. When, therefore, the owner 

 of an old established herd advertises, "No females for 

 sale," he unwittingly announces very low fertility and a 

 very dangerous herd from which to buy cattle of any age or 

 of either sex for breeding. 



5. In purchasing a foundation herd the entire group of 

 animals should, if possible, be purchased from one breeder. 

 In this manner one avoids the risk of bringing into contact 

 animals from numerous sources, each source possibly fur- 

 nishing a different type of infection of the genital organs. 

 The difficulty of determining the state of health of the pur- 

 chased animals increases as their sources multiply. Pur- 

 chasing the foundation stock from a single herd simplifies 

 the question of warranty. If a heifer or cow fails to con- 

 ceive, the seller of the group cannot shift the blame to the 

 bull, since he has made a warranty on him also. This plan 

 is also best for the seller both in fact and in policy. When a 

 breeder sells a large group of females without depleting his 

 herd, he gives indisputable evidence of the sexual sound- 

 ness of his cattle, which another prospective buyer of a 

 single sire for his established herd may accept as good evi- 

 dence that he is being offered a sound bull. 



6. The best place for a buyer to go to learn of the health 

 of the herd from which he contemplates purchasing stock is 

 to the nursery. If a large number of calves, in proportion 

 to the number of cows in the herd, is present and the calves 



