Mare. In the mare in addition to the lesions of the internal organs and blood, the following may be noted in connection with the generative system. Phlegmonous or œdematous swellings, sores or ulcers on the lips of the vulva, and on the vulvar and vaginal mucosæ. The parts become variously distorted, and the vulva, habitually open may expose the swollen and ulcerated clitoris. A crop of papules or vesicles, running into sores or ulcers may appear on the urethral orifice, the vulva and adjacent skin, and even though overlooked, their seats are marked later by loss of cutaneous pigment and the formation of small white spots. The mammæ are sometimes inflamed, œdematous and tender, with suppurative or necrotic foci and the adjacent lymph glands are enlarged by infiltration or contracted by sclerosis.
Dog. These resemble those in horses. In the bitch genito-urinary congestion, inflammation and catarrh, subcutaneous infiltration under the belly and inside the thighs, swelling of the inguinal lymph glands, emaciation, and pallor and atrophy of the voluntary muscles are marked features.
Symptoms. Horse. Incubation may last from one to eight weeks (Maresch), but is usually 11 days from the infecting service. It may be abridged by a special susceptibility, and by repeated infections and hence the more acute cases are especially seen in the male in daily service. In some such subjects local genital infiltrations are speedily followed by paralysis or vertigo which cuts off the patient in a few days.
More commonly the malady is chronic though varying in different countries, epizoötics or even in particular cases.
The first symptom is slight swelling of the anterior border and raphe of the sheath, which gradually extends backward to the scrotum and inguinal region and forward on the abdomen it may be as far as the brisket. This may be hot and painful, but is usually œdematous, cool and painless. The infiltration affects the end of the penis, the meatus may be red and angry with a slight muco-purulent discharge, and red spots vesicles and ulcers may stand out clearly on the pigmented surface. Williams never saw such eruptions in the American cases and doubts their existence except as the result of injuries. There are frequent semierections and service is still possible. Later the engorgement extends to the specially pendent testicles, inguinal glands and others adjacent. Paraphymosis is occasionally seen or, more commonly, the penis hangs out of the sheath soft and flaccid and erection seems impossible. The local swelling may become excessive, pressing the testicles up against the inguinal ring, or suppuration and extensive abscess may follow. Appetite is retained and the temperature remains moderate (100° to 102° F.).
The local swellings may almost completely subside, except a slight tumefaction of the end of the penis, hence some (Fischer) have held that the cutaneous lesions are the primary ones, yet the start of infection at the generative organs and the fact that a stallion often infects a number of mares before there is any suspicion of his own infirmity is evidence enough of the genital seat of the earliest lesions.
The cutaneous lesions, which are essentially secondary, but highly characteristic, appear from forty to sixty days after the infection (Schneider and Buffard). They are from a quarter of a dollar and upward in size (in some old horses much smaller), and rise abruptly from the healthy skin, becoming the more marked that the hairs upon them stand erect. These may arise suddenly and subside again in one day, or give out a serous exudate which mats the hairs into a tuft. They may, however, last four or five days. These are more patent after a full drink of water, or after sprinkling or sponging with water. Even when they have been overlooked these results may often be seen later on colored skins, in the presence of many circular white spots entirely devoid of pigment. The most common seat of these cutaneous lesions is the hind parts (anus, tail, croup, quarters), but they may appear on the sides, neck, shoulder or thighs.
Tenderness of the loins may now be shown, with frequent, painful micturition, but the penis becomes more and more paretic, so that coition becomes encreasingly difficult or impossible. Paresis also shows in the hind limbs, the animal remains recumbent a great part of the time, rises with difficulty, starts suddenly forward at the fetlock, and drags the toe on the ground in walking. Swelling of the joints and tendinous sheaths, with attendant lameness, is not uncommon. The appetite remains good, yet emaciation and weakness make marked progress.
The advanced stages are characterised by marked anæmia, paraplegia and dementia. The visible mucosæ are pale, emaciation advanced, the patient stubs his toes and sways in walking, and finally drops unable to rise; or he stands with hind legs straddled and semi-bent, and largely oblivious of all around him. He may be too stupid to eat unless the food is placed in his mouth, and yet the neigh of another horse or a mare may draw forth a feeble retort, as if the deranged generic instincts remained. Swelling, or even abscess of the lymph glands, axillary, submaxillary or inguinal, is usually present, and muco-purulent discharge with ulceration of the nose or eyes is not uncommon. The joints crack when moved and fractures are common.
The duration of the disease is two or three months, the progress being more rapid in winter.