122 VETERINARY STUDIES 



Bacteria frequently contaminate drinking water, which may 

 thus serve as a source of transmission for many germ diseases; 

 like anthrax, foot and mouth disease, hog cholera, and glanders. 



Animal parasites also contaminate the water supply, which 

 serves to spread parasitic diseases, intestinal parasites, for 

 example. 



Hard water may contain much calcium, magnesium, etc., and 

 is said to cause indigestion, unthrifty conditions, and perhaps 

 calculi. 



Intervals may be wrong. Horses should be watered regu- 

 larly and at as short intervals as convenient. They should not 

 be given large quantities of water sooner than one hour after 

 eating grain. Much cold water interferes with digestion, and 

 when given to a very hot or tired horse may result in founder 

 or indigestion. 



Practical application. — With this lesson in mind, the student 

 should hereafter watch for milk fever cases to see if the cow has 

 not been in good condition and rather heavily fed for a cow not 

 milking, and lacking in exercise. 



He should be on the watch for azoturia (see Lect. XLIV) and 

 learn whether the horse has not been idle and full fed during 

 the day or so prior to illness. Note also whether there had not 

 been a period of regular work on full feed before this idle 

 period. 



He should also watch for cases of heaves among horses to 

 determine whether such horses have been greedy eaters and 

 heavily fed with dusty hay or other bulky food. It will be 

 interesting for the student to be on the lookout for an outbreak 

 of hog cholera in a herd that had access to a small pond or very 

 sluggish stream, to see if there is not an unusually heavy loss 

 in such a case. 



The very hot, very tired, or very Imngry horse should be 

 fed and watered cautiously, with small quantities, until he is 

 in better condition. Sudden and radical changes from old to 

 new feed of the same kind are to be avoided. The quantity and 

 quality should be watched. Too much hay is the most common 

 error made in the feeding of horses. The working horse in good 

 condition should be fed but little on holidays. For the heavily 

 pregnant mare, excessive feeding is injurious and especial care 

 must be taken to prevent colic in such a mare. 



Diseases often associated with overfeeding are: azoturia, 



