ABOMASAL INDIGESTION. 183 



description of this disease to enable it readily to be recognised. On the 

 other hand, it is to be presumed, although final proof has certainly not 

 been furnished, that in cases of gaseous indigestion, or of impaction of 

 the rumen, the abomasum, whose physiological action is predominant, 

 must simultaneously suffer. 



Prnnary abomasal indigestion, on the contrary, is common in young 

 animals before weaning, so that the condition has been given the name 

 of "milk indigestion." It could not very well be otherwise, for the 

 abomasum is the only one of the gastric divisions which in ruminants 

 is active during the first few weeks of life. At this period it is larger 

 than the other gastric reservoirs ; and the rumen, the reticulum, and the 

 omasum do not undergo great development till weaning begins. 



Causation. Milk indigestion attacks young animals under varying 

 conditions. 



In animals suckled by the mother the disease rarely occurs, but yet 

 when the mothers are good milkers, like the Flemish, Norman, Jersey, 

 and Holland breeds, and when there is too long an interval between the 

 feeds, calves, which are naturally greedy, and in addition are hungry, are 

 apt to take too large a quantity of milk — in fact, they often gorge to the 

 fullest possible extent. Owing to its over-distended state the abomasum 

 either fails to secrete sufficient of the rennet ferment necessary for 

 coagulating the milk or secretes an insufficiently active ferment. The 

 first stage of digestion remains incomplete, giving rise to so-called 

 "milk indigestion." 



When the cows are employed in ploughing, etc., or in drawing carts, 

 not only are the calves fed at long intervals, but the milk is not always 

 of proper chemical composition even in the udder. As a result of 

 work, fatigue, over-exertion and irregular feeding, the cow's yield of milk 

 for the time is less digestible than the normal supply, or may even prove 

 irritant to the calf's stomach. Milk indigestion is thus set up. 



"When the cows are fed on factory waste, like beetroot-pulp or brewers' 

 grains, toxic or irritant products may even find their way into the milk, 

 which then irritates the little creature's abomasum and produces gastric 

 indigestion. Just as in the production of congenital alcoholism in man, 

 the young, animal is then ingesting, unknown to those responsible for 

 its well-being, chemical substances which produce various pathological 

 changes. 



But milk indigestion is commonest of all in calves fed by hand. The 

 food usually given is a mixture of milk from the previous night, and 

 skim milk or even butter milk. It contains lactic ferments and various 

 microbes, some capable of producing toxic principles. 



When swallowed and brought directly in contact with the mucous 

 niembrane these cause abomasal indigestion. 



