Diagnosis. Presumption may arise from the above mentioned symptoms, and especially the bulimia, the polydipsia, the polyuria, the rapidly advancing emaciation, weakness, and prostration and the ocular troubles, but conclusive evidence is only found in the presence of glucose permanently in the urine.
Tests for Sugar in the Urine. For one who can go through it the touching of the tip of the tongue with a drop of the suspected urine will give a prompt and reliable test.
Fehling’s cupric test is the next best for simplicity and availability. Dissolve 34.639 grammes (1⅕ oz.) pure cupric sulphate in 200 cubic centimeters of distilled water: 173 grammes (6 ozs.) of pure neutral sodio-potassic tartrate and 80 grammes of potassium hydrate in 500 cubic centimetres of distilled water. Add the copper solution slowly to the potassium one and dilute the clear mixture to one litre. One cubic centimeter of this fluid will be discolorized by 0.005 gramme of sugar; or 200 grains will be discolorized by 1 grain of sugar.
Trommer’s test is even simpler for a mere qualitative test. Pour the suspected urine, freed from albumen, into a test tube and add a solution of caustic potassa or soda until distinctly alkaline. Should this throw down earthy phosphates or carbonates filter these out. Then add drop by drop a solution of pure cupric sulphate in distilled water (3.5:100) so long as it throws down a yellowish red precipitate of oxide of copper. When the supernatent liquid remains clear and assumes a distinctly bluish tint, the sugar has all been precipitated. The amount of precipitate is a criterion of the quantity of sugar, which may be otherwise estimated by the amount of copper salt used.
The fermentation test is made by adding a teaspoonful of liquid yeast to four ounces of the suspected urine, stopping the flask lightly and placing it in a temperature of 60° to 80° F. for 12 to 24 hours when the sugar will have been converted into alcohol and dioxide of carbon. The loss of weight will indicate the amount of sugar, as also will the lowering of the specific gravity. If before testing the urine was 1060, and after 1035, it contained 15 grains of sugar to the fluid ounce.
Prognosis. This is always rendered more grave in the horse than in man, because of the impossibility of putting him on a purely albuminous diet. The great tendency is to a rapidly fatal issue, especially in cases of irremediable structural lesions in the brain and liver. Where the disorder is largely functional, as in connection with hæmoglobinuria or as the result of poisons ingested the prospect of recovery is often good.
Treatment. In cases due to poisoning the use of antidotes and eliminating agents will be effectual, and in transient and curable diseases like pulmonary disorder, hæmoglobinuria and paralysis the appropriate treatment will restore. In the more inveterate or constitutional cases all treatment is liable to prove ineffectual. At the outset some apparent amelioration may be obtained from salicylic acid, salicylate of soda, bicarbonate, acetate, citrate, sulphate or chloride of soda, nitro-muriatic acid and other cholagogues. Blisters to the perichondrium may also be employed. Later, when degeneration of the liver has reached an extreme point, these will be of no avail. Cadeac recommends acetanilid, antipyrine, and benzo-naphthol largely on their antiseptic merits, and Jong claims a recovery in a horse under daily doses of 12 grains of codeine. Opium has long been employed in man with partially good results, and croton chloral, strychnia, phosphoric acid, iodoform and ergot are recommended in different cases.
One of the most beneficial agents is skim milk or buttermilk as an exclusive diet, and this may be to a large extent adopted for the horse. Under its use the sugar may entirely disappear, and though rheumatoid pains in the joints may be brought on, these usually subside on withdrawing the source of lactic acid. They may further be met by the use of salicylates. The greatest care should be taken of the general health, an open air life, with protection against colds and storms, and a healthy condition of bowels, kidneys and skin being particularly important.
The impaired digestion and assimilation usually demand carminatives, stomachics, bitters, and mineral acids, particularly the nitro-muriatic. With the same intent a fair amount of exercise short of absolute fatigue should be secured. But each case will require a special study and treatment consonant to its special attendant lesions, its causative functional disorders, and its stage. One case may demand attention to bacteridian poisoning, one to a better regimen and diet, one to liver disease, and one to disease of the brain, etc. After this treatment specially directed to the abnormal function or structure, would come the more specific treatment for mellituria which would be more or less applicable to the general glycolytic disorder.