BREEDS OF CHICKENS 53 



That such practice, persistently followed, did not (luickly run 

 the stock out was due to these saving circumstances: (1) the 

 natural tendency of tlie stock to improve under the very 

 favorable conditions which small fiocks at liberty on farms 

 enjoyed, and (2) the occasional introduction of blood of 

 improved native stock. 



Now and then a person particularly interested in poultry 

 would breed his flock to one type or color, but the prevailing 

 belief was that the best breeding was that which combined 

 the greatest variety. 



Results of Domestication.— The general efl'ects of domes- 

 tication upon poultry have been four in number, namely: 

 (1) increased size of body, (2) increased fecundity, (3) a 

 tendency toward the suspension of the maternal instinct, 

 and (4) a lowering of the vitality of the race. 



According to Brown,' "the jungle fowl of India is a small 

 bird weighing about 35 pounds, but becomes heavier when 

 brought under domestication, even though not selected for 

 enhanced size. It does not develop much beyond six pounds, 

 unless breeding with that object in view is adopted." 



The jungle fowl usually lays two clutches of eggs a season, 

 totalling from twenty-two to twenty-six eggs. In all the 

 modern breeds there is a marked increase in production, 

 most breeds probably averaging close to a hundred eggs a 

 year. The conditions which have been responsible for this 

 have been (1) selection, (2) supplying stimulating feeds, (3) 

 comfortal)le housing, and (4) the coniparatixeh' frequent 

 gathering of eggs. Of these, the latter has had by far the 

 greatest influence. Pearl- says in this connection: 



"Egg-laying in wild birds is simply one phase of a cyclical 

 process. If the cycle is not disturbed in any way the egg 

 production is simply the minimiun required for the i)er])etua- 

 tion of the race. If, however, the cycle is disturbed, as, for 

 example, by the eggs being removed from the nest as fast 

 as they are laid, a very consideral)le increase in the total 

 number of eggs produced will result. This is, of course, 

 what happens under domestication. . . . Austen shows 



^ Races of Domestic Poultry. 

 2 Maine Bulletin No. 205. 



