coxiJirioxs Ar'i-i£CTi\(, si-:crj-.ti(i\ oi milk 2'.i 



accorflin^ t'> their causes: (i) umdiivm:, which are cuntrolled 

 kirgely In- man. anrl ( 2 1 conditions which are inherent in the cow. 



1. Some of the chief conditions which reduce the secretion oi 

 milli and are lar,<!;el\' controlled hv man are: improper care 

 and treatment of the cow. lack of proper foorl. incomplete and 

 and improper milking, irregularit}-. and long periofls between 

 milkings. Pregnane}-. nerA'ousness, or excitement of any kind 

 affects the proper working of the milk-glands considerably. 

 These latter causes. howe\'er. are not alwa}'.^ cuntrolled by man. 



2. W'ithiiut denying the inlluence of tho.^e condition^ men- 

 tinned aboA'c, the conditions which chief1\- affect the milk- 

 secreting ca])acity are inherent. It does not matter how much 

 g(Xjd care and food a cow receiAX-s, if she floes n(jt possess these 

 inherent necessary riualities. As Avas mentioned before, the 

 milk-secreting capacit\' depends upon the iiumhcr of ^laiid- 

 lobiiles, tlic iimoiDit ol blood iclik/i is supplied to these sceretory 

 parts, and the eapdcitv oj ttie eoie to digest uiul assimilate food. 

 and possibh' upon a stimulating bcxl}- fiuid not A'et well under- 

 stood. 



The number of gland-lobules is belie\'ed to increase until the 

 cow is afj(jut seven \'ears old. The milk-sccretin!.,' glands are 

 present only in a rudimentar_\' form, until the C(jw has had 

 her first calf, or is well ad^-anced in the lirst stage of i)regnanc\\ 

 The gland-l(jfjules then increase in number up io the aL,fe of about 

 seA'en. Ihe relatiA'e number ot lobules in the cow's udder can 

 (Hily be approximateh' ascertained. The size of the urlder in 

 some measure indicates this. A cow with a large flexible udder is 

 usually a good milker, due to the fact that a large Uflder usually 

 contains a large numljcr of gland-lobulo. 



The am(junt of blood which is turned through the cow's udder 

 to supply the milk-secreting cells may be approximately ascer- 

 tained by the size of the blood wssels. The blood from the heart 

 enters the udder near the region of the hips. It then passes down 

 through the udder, along the afxlomen just beneath the skin, 

 until it reaches a point about midway between the flank and the 

 girth. At this place it penetrates the abdominal wall and enters 

 the thorax. The place at which the blood penetrate^ the abdom- 



