Surgical transfer of the cysticerci of Taenia hydatigena.

Unattached immature cysticerci of Taenia hydatigena were transferred surgically to the peritoneal cavities of 4 sheep. Mature infective cysticerci were recovered from the recipient sheep 3 and 5,8 months later. A fully developed live cysticercus was present in the muscle layers surrounding the scar of the laparotomy site in 2 of the animals.

Immunization of sheep against the larval stage of Taenia multiceps.

A trial with 200 ewes and 127 lambs showed that vaccination of lambs with 2 doses of Oncosphere Secretory Antigen (OSA) 4 weeks apart, at either 4-8 and 8-12 weeks or at 12-16 and 16-20 weeks of age, was equally effective in protecting them against infestation with the larval stage of Taenia multiceps. In this trial, the lambs of ewes, vaccinated with OSA when they were 90 and again 120 days pregnant, were as susceptible to infestation as the lambs of untreated control ewes. Another trial to provoke passive immunity in lambs gave inconclusive results. In a 3rd trial 2 doses of regular OSA and 2 doses of freeze-dried OSA protected all the lambs in each group, while a single dose of regular OSA protected 9 out of 10 lambs against cerebral lesions.

Aetiology of jaagsiekte: experimental transmission to lambs by means of cultured cells and cell homogenates.

Studies on the transmission of jaagsiekte (ovine pulmonary adenomatosis) both by subinoculation of cells of known sex and by cell homogenates into male and female lambs are reported. The results obtained indicate a thymocyte-dependent rejection of male cells in female recipients in contrast to the successful transplantation of male cells in male animals and female cells in both sexes. This suggests the presence of a surface antigen determined by the gamma-chromosome in the tumour cells. A second mechanism of transmission, dependent on the transformation of the recipient's cells, was demonstrated by 2 cases of heterologous transplantation and confirmed by inoculation of cellular homogenates.

Experimental transmission of jaagsiekte (ovine pulmonary adenomatosis) to goats.

Jaagsiekte was successfully transmitted to at least 2 out of 6 goats inoculated intratracheally with partially purified jaagsiekte retrovirus. Multiple, small, well circumscribed nodules found in the lungs consisted of typical papilliform proliferations of neoplastic Type II epithelial cells. Histological evidence of a mild interstitial pneumonia in 4 of the experimental animals can probably be attributed to a contaminating lentivirus in the jaagsiekte retrovirus preparation, as suggested by the seroconversion of the animals.

The pathology of chronic Drechslera campanulata toxicosis in inbred rats.

Cultures on autoclaved maize of the phytopathogenic fungus, Drechslera campanulata, were incorporated into diets and fed to male inbred BDIX rats. In a pilot trial, a diet containing 30% D. campanulata culture material killed 5 out of 5 rats in 15-25 days. Lesions included gastric corpus erosions, gastrorrhagia and ulcerative typhlitis. Diets containing 5% or 10% culture material induced erosive to ulcerative typhlitis and oedema and hyperplasia of the ileocaecal lymph nodes in 40 out of 40 rats. Other changes included: mass loss; normocytic, hyperchromic anaemia; leukocytosis with neutrophilia; reductions in plasma proteins, creatinine, calcium and cholesterol; elevated serum enzymes; hepatosis, nephrosis and mycoplasma-like interstitial pneumonia. No lesions were present in control rats, and their profiles were normal. Ulcerative typhlitis induced by D. campanulata in rats resembles that seen in chronic piperonyl butoxide intoxication as well as that due to single treatments of indomethacid, although small intestinal ulcers are more frequent in the latter. Overgrowth of intestinal flora may be involved in ulcer pathogenesis. The pathology of drechsleratoxicosis in rats is compared to that in sheep and goats where necrotic lesions in the forestomach and, to a lesser extent, in the caecum are characteristic findings.

Notes on the toxicity and carcinogenicity of some South African cycad species with special reference to that of Encephalartos lanatus.

The South African Encephalartos species which are known or have been shown experimentally to be toxic and/or carcinogenic are reviewed briefly. The kernel of E. lanatus, the toxic and carcinogenic principle of which is macrozamin, is a potent hepatotoxin and carcinogen when fed to rats. Renal mesenchymal tumours were the most common neoplasm to be induced but hepatocellular carcinoma also developed in one animal. The potential danger to man and animals of ingestion of the seeds of Encephalartos species is emphasized.

Treatment of cerebral coenuriosis in sheep with praziquantel.

Sheep (n = 14) with coenuriosis were treated with praziquantel in single or divided doses at total dosage rates of 50 to 500 mg kg-1 live mass. Nine of the sheep also received corticosteroid, diuretic and analgesic supportive therapy. Stress was avoided as far as practically possible. Treatment of one sheep with acute coenuriosis at a total dosage rate of 500 mg kg-1 praziquantel, was unsuccessful. Eight sheep were successfully treated at total dosages ranging from 100 to 500 mg kg-1 live mass, whereas dosages of 50 mg kg-1 were successful in 2 sheep only. Dosages of 50 mg kg-1 in 2 other sheep with multiple cerebral coenuri, were unsuccessful or only partially successful in killing parasites.

Treatment of the larval stage of Taenia multiceps with praziquantel.

Five sheep were infested orally with 5,500 eggs of Taenia multiceps and were treated with praziquantel (Droncit, Bayer) when they showed typical nervous signs of coenuriasis. Two sheep were treated with praziquantel at 100 mg/kg live mass per day for 5 days, 2 sheep at the same dosage for 2 days and one animal at 50 mg/kg per day for 5 days. No viable coenuri were recovered from any of these animals. This is the only anthelmintic that is known to be effective against this parasite, but its cost is such (R200 at the lowest dose rate) that it can be economically used only for the treatment of valuable stud animals.

Preliminary report on the stimulation of immunity to the larval stage of Taenia multiceps.

The efficacy of Oncosphere Secretory Antigen (OSA) in protecting sheep against the larval stage of Taenia multiceps was assessed in 47 sheep in 2 trials. In the pilot trial no cerebral coenuri were found in 3 sheep which were treated with OSA 28 and 14 days before challenge with 6 000 eggs of T. multiceps. Cerebral coenuri were present in 3 untreated controls. In the second experiment 30 sheep were similarly treated with OSA and challenged with 5 000 eggs of T. multiceps, while 11 sheep served as untreated controls. At necropsy either developing coenuri or degenerate lesions were present in the brain of 5 (16,6%) of the 30 vaccinated animals while 8 out of 11 (72,7%) of the untreated animals had cerebral coenuri or degenerate lesions in the brain. It is concluded that OSA may be used to protect animals against cerebral coenuriosis.

Bovine cerebral theileriosis (turning sickness) with spinal cord involvement.

A case of bovine cerebral theileriosis is described in which the principle lesions occurred in the spinal cord and its meninges. These were clogging of vessels with lymphocytes, many of which were parasitised by Theileria sp. schizonts (probably T. mutans), thrombosis and infarction of nervous tissue, and lymphocytic meningomyelitis. Rare cerebral meningeal vessels showed thrombosis. Clinically the animal showed posterior paresis.

Chlamydia-induced septic polyarthritis in a dog.

A systemic disease associated with pyrexia, lymphadenopathy, and arthropathy of several joints of the appendicular skeleton in a dog is described. Chlamydia-like organisms were detected on light-microscopic examination of a smear made from joint fluid aspirated from one of the affected joints. A group-specific lipopolysaccharide antigen shared by all Chlamydia spp. was demonstrated by direct fluorescent antibody staining of joint fluid, which also proved positive for chlamydia by means of the relevant polymerase chain reaction test. An indirect fluorescent antibody test on serum was also positive, although the complement fixation test was negative. Attempts to grow the organism from joint aspirates in the yolk sac of embryonating hens' eggs and on appropriate tissue cultures, however, failed. Chlamydia spp. are considered to have played an aetiological role in this case, making it the first substantiated case of naturally-occurring arthropathy in a dog due to chlamydiosis. The origin of the infection could not be traced.

An outbreak of Cotyledon orbiculata L. poisoning in a flock of Angora goat rams.

An acute outbreak of C. orbiculata L. poisoning in a flock of 16 Angora Goat rams is described. Typical signs of acute bufadienolide cardiac glycoside toxicity were manifested and 6 animals died. In the 2 animals examined histopathologically multiple foci of myocardial degeneration and necrosis were present. Treatment consisted, inter alia, of drenching with a mixture of activated charcoal, potassium chloride and a commercial preparation, Universal Antidote (Centaur) and parenteral administration of atropine sulphate.

[Cervical intervertebral disk prolapse in a horse]. / Servikale intervertebrale diskus prolaps in 'n perd.

A Hansen type I cervical intervertebral disc prolapse was diagnosed in a 16-year-old American Saddler showing clinical signs of paresis and ataxia. An ante-mortem diagnosis was made by means of plain radiographs and a myelogram. The horse was euthanased and the diagnosis confirmed on a post-mortem examination.

Cat bite transmission of Yersinia pestis infection to man.

The transmission of bubonic plague from the kitten of a domestic cat to a man by means of a bite on a finger is described. The human case was complicated by the development of a secondary meningitis, followed, after specific therapy, by protracted recovery. The kitten showed swollen lymph nodes of the head and neck, frothing at the mouth and nostrils, and signs of an acute infectious disease which had a fatal termination. Yersinia pestis was isolated on about the 8th day from the cerebrospinal fluid of the man. The foster mother of the kitten exhibited signs of spinal and cerebral meningitis but recovered following treatment; her serum contained plague antibody levels of 1:512 and 1:1024 on the 22nd and 34th days respectively after the first evidence of illness. Three litter mates of the kitten also died. The outbreak occurred on a farm in the Graaff-Reinet district of the eastern Cape Province, which is situated about 160 km from the nearest known natural plague focus.

Swayback in a blesbok (Damaliscus dorcas phillipsi) and a black wildebeest (Connochaetes gnou).

Ataxia associated with myelopathy and low liver copper concentrations is described in a blesbok (Damaliscus dorcas phillipsi) and black wildebeest (Connochaetes gnou) from the Karoo Nature Reserve, Graaff-Reinet. This syndrome, which occurs in neonatal and delayed forms, has been described in sheep, goats, pigs and domesticated red deer, but reports in other ungulates, including antelope, are very rare and generally unconfirmed by histopathological examination. The 2 animals examined exhibited a typical pattern of Wallerian degeneration in selected tracts of the spinal cord. Many blesbok in the reserve are markedly pale in colour. Fading of the hair is also associated with copper deficiency in ungulates. High lamb mortality occurs as a result of the ataxia and threatens the survival of the blesbok herd in the reserve. Confirmation of low liver copper concentrations in affected animals offers direction towards the solution of the problem.