FARM ANIMALS 83 



jacks are kept and used for no other purpose. 

 The mule breeders of the country have realized 

 the importance of improving the mule as well as 

 other stock and have organized a jack and jennet 

 association with a registry of about 1,400 animals. 

 It has been found that jack colts are best weaned 

 at the age of six months. They are fed plenty of 

 nitrogenous material such as oats and bran with 

 hay and an abundance of green forage. The 

 percentage of mule colts obtained from jack ser- 

 vice is about one half or approximately the same 

 as is the case with horses. In breeding jacks it 

 is always to be remembered that there is some 

 aversion on the part of the mare and in many in- 

 stances the jacks may appear to be afraid of the 

 mares. It is, therefore, desirable to use a pit or 

 chute in which the mare can be confined so as not to 

 injure the jack. As already indicated the market 

 requires a dark colored mule. White, gray and 

 mouse colored mules are not desired and many 

 stories are told by army officers and others to the 

 effect that mules of these undesirable colors are 

 less hardy, more susceptible to disease than dark 

 colored mules. However that may be the public 

 demands a dark mule and this is the end of the mat- 

 ter. It is desirable, therefore, to use dark mares 

 and dark jacks in order to secure the proper re- 

 sults. 



Much controversy has raged around the point 

 of the proper size for jacks. Some breeders 

 would not use a jack above fourteen hands in 

 height, arguing that since jacks have comparatively 

 small legs and transmit these characteristics to the 

 mule colt it is impossible to secure proper pro- 

 portion in mules if too much height is obtained. 

 In other words mules with large bodies inherited 



