From experience gained both in Iceland and Norway, the disease appears to be often localised in certain districts and fields—a fact largely accounted for when we learn that up to the present little or no attempt has been made to prevent the spread of infection from the dead bodies.
Braxy chiefly attacks young animals, and is rare in those over three years of age. Hjaltelin estimates the number of deaths in a single district during the years 1849–1854 at approximately 6,000, made up as follows:—
| Yearling lambs | 2,440 |
| Two-year sheep | 2,460 |
| Three-year sheep | 1,020 |
| Animals older than three years | 80 |
The younger animals suffer most, and in Norway Nielsen directs attention to the heavy fatalities amongst lambs.
Symptoms. The sheep suddenly appears ill, is dull, lies about, and cannot be induced to rise; all movement seems to give pain, and from time to time the animal groans; the posterior parts of the body become swollen, and a little froth often escapes from the mouth. The pulse varies between thirty and thirty-five per minute, and is often imperceptible in the extremities; the temperature may rise to 105° or even 108° Fahr. This condition may last some hours, and always ends with the animal’s death; sheep, which overnight had shown no signs of illness, are often found dead in the morning. The incubation period is from forty-eight to sixty hours, but ordinary cases seldom live longer than from five to eight hours after the symptoms declare themselves.
The striking post-mortem appearances, especially the hæmorrhagic inflammation of the abomasum, were early the subject of remark. This appearance is very characteristic.
If the animals are slaughtered, the most important change is found to be a purplish, dark, somewhat swollen patch in the abomasum; during the course of the disease this increases in size, and if the animal should be allowed to die of braxy the entire abomasum shows hæmorrhagic or sero-hæmorrhagic infiltration; the abomasum and the first part of the small intestine usually contain no food, but may often show a certain amount of bloody fluid. This hæmorrhagic inflammation may extend in a forward direction, implicating the other stomachs, or backward, invading the small or both small and large intestines. The other parts of the intestinal canal are congested. The pleural and peritoneal cavities contain a little serous fluid. The blood is dark in colour, but may be clotted; the spleen is at times somewhat swollen, at others normal. The liver is usually light-coloured, soft, and degenerated; occasionally this degenerative process is extremely marked, but due allowance should always be made for post-mortem change. The kidneys may appear degenerated; in many cases they are enlarged and soft, or almost fluid in consistence. The carcase decomposes very rapidly; within a short time of death the belly is distended with gas, the rectum protrudes at the anus; the skin assumes a bluish colour in places, and the wool falls out; sometimes the skin bursts, revealing the presence in the subcutaneous tissue of a sero-hæmorrhagic fluid.
Fig. 205.—The shaded areas of the above map indicate the distribution of braxy.
Braxy is, then, a primary violent hæmorrhagic inflammation of the abomasum, with or without secondary general infection.