1920.] 



Breeding Dairy Cattle. 



657 



approximately equally in both herds, and if one bull were found 

 to be of great dairy prepotency, he would be kept as long as 

 possible for mating with mature and unrelated cows. Under 

 these conditions, however, judicious in-breeding most probably 

 would give very satisfactory results. Such a scheme could be 

 worked equally well with three participants. The same system 

 could be followed without the risk of differences of opinion 

 where one owner maintains a large herd or has cows at two or 

 more homesteads. Young bulls would be required from time to 

 time for mating with heifers, as is the custom at present. 



The co-operative societies of small holders organised under 

 the Ministry of Agriculture's Live Stock Improvement Scheme 

 could adopt the tested sire system. Bulls could be transferred 

 from one society to another, and the societies would have the 

 advice and assistance of the Live Stock Officer at all stages. 

 The period necessary for a progeny test could also probablv 

 be shortened by good management and feeding of the young 

 stock, and by mating at an earlier age than usual. 



Owners of pedigree herds who have confidence in the bulls 

 they offer for sale might also come to some agreement with 

 purchasers as to the retention of a bull for the necessary time, 

 since, when a specially good bull is found, the family from which 

 he is bred immediately increases in value. 



Progeny Tests of Cows. — Tests of the power of transmission 

 of dairy qualities in cows are not, of course, of the same import- 

 ance as in the case of bulls. A cow will, on the average, have 

 but five or six calves in a breeding herd, and as only half of 

 these may be heifers, individual cows with the maximum power 

 of transmission can, through their female progeny, make only a 

 small contribution to the improvement of the herd. The basis 

 of selection of cows for breeding must, nevertheless, be facts — - 

 not opinions — hence the need for a great development of milk 

 recording to supply information on the degree to which dairy 

 qualities are possessed by cows in the herd. The need for con- 

 stitution must also be kept in mind; and, lastly, " foundation " 

 cows should exemplify to a marked degree the type and 

 characteristics of the breed. 



Registers of Heavy-milking Cows and of Dairy Bulls. — 

 Reference may also be made to the formation of registers of 

 heavy-milking cows in relation to the breeding of dairy bulls. 

 Registers of cows complying with certain conditions as to 

 minimum yield, and other particulars, are now compiled by the 

 Ministry of Agriculture, the Dairy Shorthorn Association, .and 

 at least one Breed Society, and one of the advantages claimed 



