CHAPTER VI. 



DISTURBANCE IN THE MILK SECRETION AND 

 CHANGES IN THE MILK. 



Changes in the milk are so common and play so important a part 

 in the milk industry that it is absolutely necessary to mention the 

 more important, the country veterinary surgeon l)eing frequently con- 

 sulted on this point. 



The udder acts as a natural emunctory, just like the kidney, by 

 which are eliminated, in consequence of special selective i)roperties, 

 certain natural principles (the active principles contained in the forage 

 and other food, vegetable alkaloids, etc.), drugs (alcohol), and poisons 

 (nicotine). This physiological peculiarity explains the influence of 

 changes of diet on the composition of the milk in mothers and on 

 the condition of their offspring. In the human species it also explains 

 congenital alcoholism in children, and a number of diseases whose 

 cause was formerly unknown. 



Agalaxia. — This term implies a temporary or definite arrest of 

 the milk secretion. In many instances it represents nothing more 

 than a disturbance in the physiological function of the gland, but in 

 others it forms a true diseased condition. 



Thus it is beyond dispute that psychical influences may produce 

 disturbance in this respect. Temporary suspension in the secretion as 

 a consequence of removal of the offspring from its mother, especially 

 when the young animal has been sucking for several days or weeks, 

 is a fact very well known to all breeders. 



Under ordinary circumstances, however, the reasons are quite 

 different, and when the secretion of milk is diminished or suppressed 

 it is due to the ingestion of plants, substances, or drugs which check 

 the secretion of milk. All the Solanaceae (belladonna, hyoscyamus, 

 stramonium, woody nightshade, etc.), certain uniljelliferfe (hemlock), 

 colchicum, etc., have this effect. 



As to agalaxia of a true pathological character, it occurs in debili- 

 tating and grave diseases, and sometimes follows certain contagious 

 forms of mammitis complicated with sclerosis of the udder (infectious 

 agalaxia of goats). 



