1917] ANIMAL PRODUCTION. 369 



Practically all of the 1,000 birds in the contest received the agglutination 

 test for bacillary white diarrhea. Twenty-eight birds in 14 pens reacted posi- 

 tively to the test. In 4 of these 14 pens there were, respectively, 3, 4, 5, and 6 

 reactors. The average individual egg yield of these 4 infected pens was 130 

 eggs. 



There was a loss by death during the contest of 10.4 per cent of the hens. 

 About one-third of the deaths were due to various disorders of the reproductive 

 system, and one-fourth to hypertrophied or enlarged livers. 



In this contest the Plymouth Rock eggs averaged 2G.4 oz. per dozen, the 

 Rhode Island Red eggs 24.4 oz., the White Leghorn eggs 23.8 oz., tlie Wyandotte 

 eggs 23.5 oz., and the remaining breeds 24.3 oz. The average weight of all eggs 

 was 24.3 oz. per dozen. The number of eggs laid per month varied from 5,291 

 in November to 19,986 during May. The average value of all the eggs was 34.54 

 cts. per dozen, and the highest gross receipts for eggs was made in August. 



The percentages of broody hens averaged from 13.6 for the White lieghorns 

 to 65.6 for the Rhode Island Reds, the average for all the breeds being 39.3. 

 Tlie average number of days lost by each broody hen was 52.8. It is estimated 

 that the combined loss in egg yield in this contest due to the 887 broody periods 

 was 688.5 dozen eggs, worth $237.81. 



Tabulated data show the amount and cost of feed consumed, the number of 

 eggs produced with their average weight and total value, and the returns above 

 feed cost for each pen in the contest. The average amount of feed consumed for 

 all breeds was 4.48 lbs. for each pound of eggs laid, or 6.81 lbs. for each dozen. 

 The cost of feed (including grit, shell, and charcoal) per dozen eggs produced 

 was 12.7 cts. for the Leghorns, 13.2 cts. for the Wyandottes, 15.1 cts. for the 

 Rhode Island Reds, 15.5 cts. for the Plymouth Rocks, and an average of 14 

 cts. for all breeds. The cost data are based on a hundredweight valuation of 

 $1.93 for mash, $2.11 for grain, .$0.75 for grit and oyster shells, and $2 for 

 charcoal. The cost of green food is estimated at 10 cts. per bird. 



The text of the rules and regulations governing the contest, together with 

 general information and suggestions, is included. 



Breeding for egg production. — I, A study of annual and total production, 

 E. D. Ball, B. Alder, and A. D. Egrert (Utah Sta. Bui. 1^8 {1916), pp. 3-60, 

 figs. i2).— Continuing previous work (E. S. R., 32, p. 73), this bulletin reports 

 the results of a study of eight years' records of a flock of White Leghorn hens, 

 with a similar study on the production of each successive flock of the unselected 

 descendants. » 



From the data collected it is concluded that " the production of unselected 

 White Leghorns varies widely in different years as influenced by the environ- 

 ment, but from all available records averages about 130 for the first year, 120 

 for the second, and less than 110 for the third, drops to about 85 in the fourth, 

 and falls about 10 eggs a year after this up to the eighth year. Selected flocks 

 have averaged 160 in America and 190 in Australia. The American record 

 corresponds closely to the average of the upper one-half of the unselected flocks 

 and indicates that the selection has been able to eliminate the lower half." 



The first-year production of a flock of White Leghorns Is considered to be no 

 indication oi their total production. If the first year's production is high, the 

 second will be low, and vice versa. The total production in three years, how- 

 ever, will in all cases be about the same. " If the first year record of a flock is 

 high, selection of the high layers will materially improve the later production 

 of the flock. If the first record is low, there will be little value in selection, 

 as even the lowest producer will make a second-year record above the general 

 average. The three-year average is in all cases a much more reliable indica- 

 tion of productivity." 



5750°— No. 4—17 6 



