40 MANAGEMENT AND FEEDING OF SHEEP 



protection from rainstorms will result in loss of yolk in 

 the fleece of coarse wool sheep, and a massed and pasty 

 condition of yolk in that of fine wool breeds. Too much 

 protection will unsettle equilibrium in the consistency of 

 the yolk through an excess of heat. Lack of care will, 

 of course, neutralize the effects of good feeding in pro- 

 portion as it exists. 



Breeding, accompanied by careful selection, is more 

 potent in bringing about modifications in wool produc- 

 tion than any other influence. The influence thus ex- 

 erted relates to increase or decrease in the number of 

 the wool fibers, to the length of these and to the size and 

 strength of the fiber. Breeding without selection and 

 selection without breeding will effect such changes, but 

 very much more slowly than when these act in conjunc- 

 tion. Even when acting in conjunction, the changes ef- 

 fected are slow. A few generations of judicious breeding, 

 accompanied by selection, will enable the breeder to 

 change the form to meet the requirements of modification; 

 but many generations may be required to effect the same 

 in regard to wool. The exact method of securing these 

 modifications cannot be discussed here, they are so many 

 and so various. But attention should be called to the 

 modifications in wool production in the evolution of the 

 Rambouillet and Delaine breeds from the American Me- 

 rino, which are now matters of history. 



The trend of the influence exerted by age and size 

 on wool production is the same in all breeds. The differ- 

 ence is one rather of degree than of kind. It would seem 

 correct to say that, as a rule, the heaviest fleece shorn 

 is that first taken from the sheep, and that decrease fol- 

 lows in an increasing ration as age advances. The said 

 decrease is not usually marked in the second shearing. 

 With Merinos it is claimed that in some instances there 

 is no decrease. The decrease extends not only to the 

 weight of the wool, but also to the length and the amount 

 of the yolk produced. In some breeds it is seen in the 



