DAIRYING 



45 



PLATE 5 THE MAMMARY GLAND 



udders, a development of the fore udder by selection and breeding 

 will undoubtedly have a tendency to increase the yield of milk. 



Z. Milk Secretion. 



204. The secretion of milk is a process that is not thoroughly 

 understood in all its details. It is known however, that there are 

 only two mammary glands in all mammals. The number of lobes 

 or teats on each gland varies however, with different animals from 

 a large number, as in the case of the sow, to one teat on each 

 gland as in the goat's udder. The cow usually has two teats on 

 the right and two on the left gland. Occasionally a tliird, smaller 

 teat occurs on the udder of some cows. The two glands of f he 

 cow are separated by a membrane or partition, the ligamentum 

 suspensorium mammarum* which helps to support the udder and 



* Kirchner Milchwirtschaft. 



