LECTURE XXI. 

 CAUSES AND PREVENTION OF DISEASES. 



FOOD. 



Food may be a factor in animal disease when excessive in 

 amount, insufficient, too concentrated, too coarse, bulky and in- 

 nutritious for the animal that receives it ; poor in quality ; when 

 given in a poorly balanced ration or at irregular or improper 

 intervals ; when given a very tired or hot animal ; when carrying 

 vegetable or animal parasites; or when suddenly changed; e. g., 

 poor to rich pasture and when poisonous. 



Excessive amount. — Common tendency to overfeed, results 

 in azoturia, heaves, colic, etc., among horses; milk fever, etc.^ 

 among cows, and favors the development of all febrile diseases. 

 Only a certain amount can be absorbed or used, the remainder 

 causes trouble. 



Deficiency predisposes to all diseases that are favored by a 

 lessened vitality. Glanders and similar diseases are especially 

 apt to occur or to increase in severity among horses that are 

 poorly fed. Deficiency in food mineral matters predisposes to- 

 ward certain diseases of bone. Deficiency of albumin results 

 in loss of energy and strength and animals so fed are apt to be 

 languid and weak. 



Coarse, bulky and innutritions food may cause colic, indi- 

 gestion, heaves and impactions, especially apt to cause trouble 

 with animals with small stomachs; e. g., horse. 



Poor quality, e. g., hay cut too ripe or rained on after cut, 

 light oats, etc. Objections same as deficiency, also favors colic, 

 impactions and anaemia. 



A food may be poorly balanced and dangerous though very 

 nutritious; e. g., beans, wheat, oil meal and cotton seed meal 

 contain alone too much protein and not enough ash, fat and car- 

 bohydrates. When fed in the unbalanced ration such excess of 

 protein may cause febrile disturbances, diarrhoea, congestion of 

 the liver, azoturia and milk fever. A similar excess of carbo- 



