Age at death from natural scrapie in a flock of Suffolk sheep

This study deals with natural scrapie in a flock of Suffolk sheep being bred to maximise the incidence of the disease and shows that with succeeding generations the incubation period of the disease became progressively shorter until the flock died out. The most likely explanation for this phenomenon is considered to be an increase in the load of infection.     

Food aversion learning: ability of lambs to distinguish safe from harmful foods

We studied the ability of lambs to select safe foods in the presence of harmful foods. In a series of feeding experiments, 3- to 6-mo-old lambs were offered a choice between 1) a familiar, safe and a novel, harmful food, 2) a novel, safe and a novel, harmful food and 3) a familiar, harmful and a novel, safe food. All harmful foods were palatable feeds that had been treated with lithium chloride (LiCl), a non-lethal gastrointestinal poison. When lambs ingested a meal composed of a novel food containing LiCl and a familiar, safe food, lambs subsequently avoided the novel food. Lambs avoided the novel food even when the familiar food contained LiCl. The response of lambs varied when lambs were given a choice between a novel, safe food and a novel food containing LiCl. Lambs either avoided the novel food containing LiCl and ingested the safe food or they limited their intake of both novel foods. Their response was dependent on the novelty of the food containing LiCl. When a novel, palatable food contained 2% LiCl, lambs always ate some of the food, even after experiencing illness from ingesting it. Lambs experienced with foods containing LiCl displayed greater food neophobia than lambs naive to LiCl-treated foods. Thus, novelty was the major criterion that lambs used to associate foods with gastrointestinal illness.     

Cytological, Immunocytochemical and Ultrastructural Study of the Adenohypophyseal Pars Distalis of the Kid (Capra hircus): The TSH cell

The structure and ultrastructure of the adenohypophyseal pars distalis in kids of the Murciano-granadiana breed (18 males and 12 females), aged 2-3 months and with an average carcass weight of 8 kg has been studied. Techniques of staining (Tetrachrome Herlant's, and Cleveland-Wolfe) and histochemistry (PAS, PAS-OG and BA-PAS-OG) contrasted with immunolabelling (PAP) have been used. In addition an ultrastructural study has been made and nucleus and cytoplasm, secretory granules, mitochondria and lysosomes have been measured with a semiautomatic image analyzer (IBAS-1). TSH cells are found in sagittal section in the anterior area and in an antero-caudodorsal band, and transversally in the ventral and medial region; they are 6% and their average size is 14.15 microns. Ultrastructurally they are a single cellular type with spherical granules whose size is 195 nm in males and 149 in females; these granules are characterized by a clear halo and a variable electronic density. The rough endoplasmic reticulum is found as slightly enlarged vesicles with a homogeneous and moderately electro-dense content or in concentric stratifications.     

Characteristics of Salmonella isolated from an outbreak of equine salmonellosis in a veterinary teaching hospital

During an outbreak of equine salmonellosis in a veterinary teaching hospital 20 Salmonella isolates were cultured from sick horses (13 isolates) or from the hospital environment (7 isolates). Three serotypes were isolated from the environment including: S. give, S. newportand S. agona. The serotypes isolated from horses included: S. give, S. newport and S. anatum. Examination of antibiotic profiles, presence of plasmids, production of bacteriocins and hemagglutination of erythrocytes implied a common origin for the equine and environmental isolates.     

Unilateral arytenoid lateralisation: An assessment of technique and long term results in 62 dogs with laryngeal paralysis

Sixty-two dogs with laryngeal paralysis were presented over a three year period. Presenting clinical signs included inspiratory stridor (100 per cent), exercise intolerance or syncopal episodes (81 per cent), loss or alteration in phonation (48 per cent) and coughing or gagging when eating (29 per cent). Causes of the paralysis were determined as traumatic (two dogs), neoplastic (two dogs), iatrogenic (two dogs), congenital (one dog) and idiopathic (55 dogs). Unilateral arytenoid lateralisation was performed in all dogs. The perioperative complication rate was approximately 10 per cent, while the success rate as judged by owners one year postoperatively was greater than 90 per cent. The technique avoided many of the recorded complications of intralaryngeal surgery. Operative times were short and the requirement for postoperative monitoring was minimal. Increasing familiarity with the technique favourably influenced the incidence of complications and the success rate.     

Pulmonary squamous cell carcinoma with multiple digital metastases in a cat

A 14-year-old domestic shorthaired cat was presented because of swelling of the digits and lameness. A solitary lung mass was observed on thoracic radiographs. Clinical and pathological evaluation confirmed a primary pulmonary squamous cell carcinoma metastatic to a single digit on each foot. Other metastatic lesions were present in the left popliteal lymph node and in the left iliac vein.     

The heterogenicity of Cowdria ruminantium stocks: cross-immunity and serology in sheep and pathogenicity to mice

Ten stocks of Cowdria ruminantium (Ball 3, Breed, Comoro, Germishuys, Kümm, Kwanyanga, Mali, Mara, Nonile and Welgevonden) were compared from a cross-immunity, serological and mouse pathogenicity point of view. They were found to differ in varying degrees. Except for the Ball 3, Comoro and Germishuys stocks that were similar but not identical, there was no pattern in the antigenic diversity of the 10 stocks. The Welgevonden stock emerged as the stock that elicits an immunity against most of the South African stocks. The inability of the reference Ball 3 stock to protect sheep against no fewer than 6 other stocks questions the advisability of retaining this stock as the vaccine stock. The antigenic diversity of the 10 stocks could not be correlated with the antibody levels detected with the indirect fluorescent antibody test, since the sera against all 10 stocks reacted positively to the Kümm stock antigen and the variation in titres was not stock-related.     

The woolly monkey (Lagothrix lagothricha): a possible model for human hypertension research

The anatomical-pathological findings of 15 woolly monkeys were comparable with those described in man with essential benign or malignant hypertension. Kidneys revealed arterio- and arteriolosclerosis or an onion peel-like proliferation, in some cases necrotizing endarteritis. Obesity due to restricted physical activity, unnatural feeding, and psychical and physical stress could have contributed to the development of this condition. Further, high vulnerability of the genus woolly monkey is postulated. Thus, essential hypertension of woolly monkeys appears to be a multifactorial disease.