10 THE REPORT UPON No. 36 



the ever-increasing demand for advanced research with the diseases of fur- 

 bearing animals. An exhibition pen and look-out tower were built at the 

 entrance to the Farm. The pen contains one specimen of animal of each variety 

 kept, so that the general public, other than fur farmers, may have an oppor- 

 tunity of observing them and becoming familiar with their characteristics. 



Inbreeding experiments from previous years were carried on with silver 

 foxes. It has been found that where brother and sister were mated together 

 for the third generation there was a decided decline in prolificacy; the number 

 of pups per litter showing a distinct decrease from year to year. On the other 

 hand, line-breeding, mother to son, father to daughter, produced exceptionally 

 high quality pups. 



Interesting but not conclusive results were obtained in the breeding of cross 

 foxes. With red females mated to silver black males variable results were 

 obtained. In some cases the progeny were well marked high class cross fox, 

 in others the progeny were either red or pointed. In this connection one valuable 

 observation has been made, namely, that cross fox trapped in the open invariably 

 produce pups with the cross marking when mated either with silvers or red 

 foxes. It may be possible through the use of these foxes to establish a true 

 breeding strain of fox. These experiments are being carried on and it is hoped 

 to establish definite data in this respect within a few years. 



Breeding experiments with mink were confined to general observations on 

 their habits and the most satisfactory method of handling them during the 

 breeding season. The polygamous system, whereby the male is introduced to 

 the female daily until she breeds, is considered more satisfactory than pairing 

 them off for the season. Not only can fewer males be kept but definite data 

 can be obtained on the breeding qualities of both the male and female. One 

 vigorous male mink can mate at least with four females. Some males are timid 

 and are frightened if the female is at all vicious. When the polygamous mating 

 is used such males can be eliminated with a consequently higher percentage of 

 producing females. The gestation period with mink is very irregular, ranging 

 from forty-three to sixty-two days with the stock at the Fur Farm. A number 

 of the females will accept the male from the eighth to the eleventh day after the 

 first mating, consequently it is safer to try them out at this date regardless of 

 whether the first mating was successful or not. The females are excellent 

 mothers, attending to their young with great care, and if properly handled 

 show little fear of the attendant. The breeding season with mink appears to 

 commence on the third of March. 



Satisfactory results were obtained with raccoon, thirty-one young were 

 born from five breeding females, one raccoon having a litter of eight. It is 

 necessary to separate the females before the young are born. Raccoons will 

 eat each other's young whenever a chance is provided. One male can be paired 

 off with at least four females during the winter. 



Somewhat radical changes from the customary methods of ^'ceding fox 

 pups were made this year. The prevalent idea that fresh meat should be 

 excluded from the diet of the female when she commences to carry feed to her 

 young was entirely disregarded. Under natural conditions the fox would bring 

 into the den, rabbits, mice and other small carnivore. Consequently fresh 

 meat and small bones would constitute the first meals of the young pup. Follow- 

 ing this line of reasoning, the standard ration consisting of raw meat or fish, 

 ground bone-meal, raw vegetables and cereals was fed through the entire nursing 

 and weaning period to the female. After weaning, the pups were placed on the 

 same ration, with the exception that one egg per day for four pups was added. 



