The term calculus denotes a stone or gravel, or unorganized concretion found in the body, as in the bladder, gall-ducts, kidneys, etc. Biliary calculi are usually formed in the gall-bladder, and their passage down the duct or canal into the intestine is if they are large, attended with the severest pain. The reasons for their formation are not understood; it is presumed that certain constituents of the bile are deposited in consequence of the presence of mucus in the gall-bladder or ducts, as the result of inflammation. Other reasons are assigned, but sufficient evidence to substantiate these theories is yet to be secured.

Symptoms

The presence of calculi in the gall-bladder cannot be determined until their passage out is commenced, and then only when they are of sufficient size to distend the walls of the canal. Pain is the prominent symptom and is of so violent a character in some cases the suffering is extreme. The occurrence of the pain is usually abrupt, no indications of ill health preceding it.

Vomiting sets in early and continues throughout the attack. The expression and manner of the animal are indicative of the great distress he is experiencing. The bowels are constipated, and in many cases if a movement occurs the discharges are clay-colored. Unless the attack is of long continuance the pulse shows but little change from the normal. The pain may be persistent without intermission, or it may take on a paroxysmal form, vary in intensity and finally end as abruptly as it first appeared.

Treatment

Opium in full doses is the only agent to be relied upon. Astonishing quantities of this drug will be borne and little or no effect be observed. Of the solid opium the dose is one grain every two or three hours or until the pain is controlled. If vomiting contra-indicates its use by the mouth, one eighth of a grain of morphine should be given subcu-taneously or double that dose by anal injection. If relief is not secured by this treatment the animal should be etherized and kept so for a time, then allowed to return to consciousness, and if the pain still persists the ether should be re-applied. It must be remembered that opiates need to be given with great care and not too often. While the pain is intense it antagonizes the narcotics and no harm results, but the gall-stone may suddenly pass from the duct into the intestine and then the pain will at once cease. If the system is too heavily loaded with opium, its antidote the pain being no longer present, the result is poisoning by the drug.

Various agents have been suggested to act as a solvent on the calculi and thereby prevent a recurrence of pain, which is almost certain to follow sooner or later, but it has not been proven that their use has resulted in marked success.