Common Diseases of Farm Animals

by Robert Alexander Craig

The quantity of urine secreted within a given time varies in the different species and at different times in the same individual. In the horse the quantity secreted in twenty-four hours varies from twelve to fifteen pints; in cattle from ten to forty pints; in sheep from one-half to one and three-quarter pints. The normal color of the urine varies. In the horse it is yellow or yellowish-red; in cattle and sheep yellowish; and in the dog a straw yellow. The specific gravity varies with the quantity secreted and the ration fed. When the quantity of urine secreted is above the average, the specific gravity is usually low.

THE NECESSITY OF EXAMINING THE URINE.—In diseases of the urinary apparatus, a careful examination of the urine is very necessary in order to be able to form a correct diagnosis. In domestic animals it is impractical to attempt to determine the exact amount of urine passed within a certain time, but we can make a general estimate of the quantity passed by carefully observing the animal and noting the condition of the bedding in the stall. The sample of urine to be examined is best taken from urine collected at different periods during the day. We should note its color and consistency. The different substances in the urine can be determined only by determining the specific gravity, testing with certain chemical reagents and by making a microscopic examination of the sediment. Normal urine from the horse may be turbid or cloudy and more or less slimy, because of the presence of mucin. This is less true of other species. In disease the color of the urine may be changed to a pale yellow, red or brown. For example, in congestion of the kidneys the urine is light in color and rather transparent; in southern cattle fever it may be red; and in azoturia it may be brown.

EXCESSIVE URINATION.—The horse is the most common sufferer from excessive secretion of urine. The most common causes are musty feeds, such as hay, grain and shipped feeds. New oats, succulent feeds and acrid plants may sometimes cause it. In the fall of the year, when the season is changing from warm to cool weather and the horse eliminates less water from the body by way of the skin, the kidneys may become more active and the quantity of urine secreted be greatly increased. This, however, is a normal physiological condition and should not be confused with this disease.

The first symptom noted is the frequent passing of a large quantity of urine. The animal drinks more water than usual and the appetite is poor. Dulness and a weak, emaciated condition are prominent symptoms. Death occurs unless the cause of the disease is removed. If the poisonous substance has been acting for some time, it is difficult to cure the animal.

This disease can be prevented by eliminating spoiled feeds from the ration fed to animals in our care. Early in the attack the necessary attention to the ration and the feeding of a clean, nourishing ration is sufficient to correct the disease. The quantity of water drunk by the animal should be limited. Complete rest is indicated. Laxatives, stimulants and tonics should be given if necessary.

NEPHRITIS.—Congestion and inflammation of the kidneys commonly occur in mixed and specific infectious diseases, such as septicaemia, pyaemia and influenza. The toxic effect of spoiled feeds, impure drinking water, and irritating drugs like cantharides and turpentine may so irritate the kidneys as to cause them to become inflamed. Chilling of the skin and nervousness or extreme fear may sometimes cause a congestion of these organs. Inflammation of the kidneys is a common complication of azoturia. Irritation from parasites should be included among the causes of this disease.

The symptoms vary in the different stages of the disease. During the period of active congestion the quantity of urine secreted is increased. The scant secretion of urine, dark in color and thick or turbid, is suggestive of an inflammation of the kidneys. The animal moves stiffly, the back may be arched, urination is painful and the urine is passed in very small amounts. The appetite is irregular or suppressed, the pulse strong at first but later small and weak, and the body temperature is elevated. On making a rectal examination we find the bladder empty and the kidneys enlarged and sensitive.

When the kidneys become so badly diseased that they can no longer perform their function of separating from the blood the nitrogenous end-products of digestion, uraemic poisoning occurs. In this later stage of the disease the animal staggers about if moved, and finally goes down in the stall and is unable to get up. Death is usually preceded by convulsions and coma.

The prognosis is very unfavorable, death occurring in the majority of cases. In azoturia of horses and in infectious diseases, the inflammation is nearly always acute. The color of the urine, its high specific gravity and the small quantity passed are valuable symptoms to consider in the recognition of this disease. Chronic inflammation generally develops slowly and may not give rise to any very prominent symptoms at first.

The preventive treatment of nephritis consists in careful nursing of animals affected with acute infectious diseases, a clean water supply and avoiding the feeding of spoiled feeds. The curative treatment is largely careful nursing. The animal should be given comfortable, well-ventilated quarters and complete rest. Chilling of the skin should be especially guarded against by protecting the body with heavy blankets and applying roller bandages to the limbs when necessary. The diet must be of such a nature as not to increase the work of the kidneys. For the first few days the animal should receive very little feed or water. Later a sloppy diet of sweet milk, green feed and mashes should be fed. Such purgatives as aloes and Glauber's salts are indicated at a very early stage in the disease. We must encourage the elimination of waste products by way of the skin in the larger animals by vigorous rubbing, blanketing and the administration of such drugs as pilocarpine. If the animal becomes weak, general and heart tonics may be given.