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CROSSBREEDS DO NOT PAY AS WELL AS PURE BREEDS. 



(Prof. J. E. Rice, Cornell University.) 



CROSSBREEDING EXPERIMENTS WITH WHITE LEGHORNS AND BARRED PLY- 

 MOUTH ROCKS TO COMPARE WITH PURE BREEDS. 



In connection with the discussion of constitutional vigor some- 

 thing should be said in regard to crossbreeding. We ought not to pass 

 without emphasizing the importance of keeping pure bred poultry, 

 and that very little if anything is to be gained by crossbreeding or 

 grading, and certainly nothing is to be gained by keeping mongrel 

 stock when compared to pure breeds. 



THE RESULT OP OUR FIRST YEAR'S WORK IN CROSSBREEDING. 



There are only one or two points that I will make in this connec- 

 tion. First, in so far as the results on egg production are concerned, 

 we gain nothing in either of the crosses with the Leghorn on Rock or. 

 Rock on Leghorn, when compared to pure bred Leghorns. The Leg- 

 horns laid more eggs than the Barred Rocks or either of the crosses. 

 Moreover, the crosses gain nothing in size or vigor over the Barred 

 Rocks when kept pure. We received from the White Leghorn pullets 

 an average production of 182 eggs apiece, from the Barred Plymouth 

 Rock pullets 129, and the cross of the Rock on Leghorn hens 153 eggs 

 per hen, and the cross of the Leghorn male on the Barred Plymouth 

 Rock hens an egg production about halfway between the Leghorns 

 and Barred Plymouth Rocks. In regard to size, we see that at seven 

 months of age these pullets of pure bred Leghorns weighed 3.42 

 pounds and the Barred Plymouth Rock pullets 5.05 pounds. The 

 crossbred stock of the Barred Plymouth Rock on White Leghorn hens 

 weighed 4.35 pounds, which is a combination of these two, that is to 

 say, that the chickens were larger than Leghorns and smaller than 

 Barred Plymouth Rocks, and in the case of the cross of the White 

 Leghorn male on Barred Plymouth Rock hens, we have a chicken that 

 is larger than Leghorns and smaller than Barred Plymouth Rocks, 

 but larger than the crossbred Barred Plymouth Rock on Leghorn 

 hens. The effect is that in this experiment the size and shape was 

 determined by the male rather than by the female, because all of these 

 chickens on the cross of the Barred Plymouth Rock male on the Whiu- 

 Leghorn hens were Barred Plymouth Rock shape and approached the 

 Barred Plymouth Rock size, whereas all of these chickens, both male 

 and female, in the cross of the White Leghorn male on Barred Ply- 

 mouth Rock hens were Leghorn-shaped and approached the Leghorns 

 in size, and neither of them was as good as a pure bred Barred Rock. 

 We gained nothing in constitutional vigor, egg production or meat 

 production over the pure breds, but we did do this, namely, by bring- 

 ing together two magnificent pure bred varieties single comb White 

 Leghorns and Barred Plymouth Rocks, which has taken somebody from 

 iifty to sixty years to develop in pure breedness, we have in one season 

 undone the careful breeding of half a century. Another fact to be 

 noted is that here we have crosses of violent contrasts. Just what 

 would take place in a cross of fowls that are more closely related in 

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