56 SCIENCE AND PRACTICE OF DAIRYING. 



yearly, the amount that is obtained, on an average, is only about 50 to 

 70 kilos. (110 to 154 Ibs.). If the average weight of a sheep be taken at 

 40 kilos. (88 Ibs.), and the yield of milk annually at 60 kilos. (132 Ibs.), 

 the sheep may be said to give a half more milk than its live weight. 

 Sheep carry their young, on an average, 154 days. The lactation period 

 may last about four months, and the time during which the sheep yields 

 milk from four to six months in the year. Examination has shown that 

 sheep's milk is, on an average, of the following composition : 



Water, 83*0 



Fat, 5-3 



Caseous matter, 4'6 



Albumin, 17 



Milk-sugar, 4*6 



Mineral matter, -8 



100-00 

 Total solids, 17*00% 



The specific gravity of sheep's milk probably lies between 1*035 and 

 T041 at 15 C. The tables, which are suitable for reducing the specific 

 gravity of cows' milk at any temperature to 15 C., are not available in the 

 case of sheep's milk. The results of seven years' consecutive examination 

 of sheep's milk of old milking (of the Boldebucker) breed, at Raden, by 

 the author, gave an average specific gravity of 1*0369 at a temperature 

 between 12 and 18 C. The average composition was as follows: 



Water, 75*400 



Fat, 11-773 



Caseous matter, 6*475 



Albumin, 1*639 



Milk-sugar, 3*651 



Mineral matter, 1*062 



100-000 

 Total solids, "24*600% 



It is well known that the most celebrated of French cheeses the Roque- 

 fort is made from sheep's milk. 



24. Mares' Milk and Buffalo Milk. Mares' milk has been made 

 the subject of searching investigations, because some nomadic 

 horse-rearing tribes inhabiting the steppes of the south of Russia 

 and the interior of Asia prepare Koumiss from it a beverage 

 which has been thought to have a good effect in certain diseases. 

 In Germany, mares' milk is never obtained or used, because Koumiss, 



