Cutaneous antigen-antibody reactions in the sheep

Abstract

Extract

It is clear that the early permeability response in the sheep that follows chemical and thermal injury, is mediated by histamine (Lancaster and Vegad, 1967 Lancaster, M. C. and Vegad, J. L. 1967. Suppression of the early inflammatory response in the sheep by strophanthin G. Nature, Lond., 213: 840–841.  [Google Scholar]; Vegad, 1971a Vegad, J. L. 1971a. Effect of thermal injury on vascular permeability in the sheep. Indian J. exp. Biol., 9: 111–112.  [Google Scholar], b Vegad, J. L. 1971b. Leucocyte emigration following intradermal injection of histamine, 5-hydroxytrypta-mine and bradykinin in the sheep. Indian J. exp Biol., 9: 113–114.  [Google Scholar]). This is similar to the situation in the rat and the guinea-pig (Spector and Willoughby, 1965 Spector, W. G. and Willoughby, D. A. 1965. The Inflammatory Process, Edited by: Zwiefach, B. W., Grant, L. and Mc-Cluskey, R. T. 427–427. New York: Academic Press. In [Google Scholar]). In contrast to the situation in the rat and the guinea-pig, various nucleosides (Vegad, 1970c Vegad, J. L. 1970c. Effect of hyaluronidase and nucleosides on vascular permeability in sheep and its suppression by mepyramine maleate. Indian J. exp. Biol., 8: 141–142.  [Google Scholar]), hyaluronidase (Vegad, 1970c Vegad, J. L. 1970c. Effect of hyaluronidase and nucleosides on vascular permeability in sheep and its suppression by mepyramine maleate. Indian J. exp. Biol., 8: 141–142.  [Google Scholar]), 5-hydroxytryptamine, turpentine-induced pleural exudates and the lymph node cell extracts also release histamine in the sheep skin (Vegad, 1967 Fischel, E. E. and Kabat, E. A. 1947. Quantitative study of Arthus phenomenon induced passively in rabbit. J. Immun., 55: 337–343.  [Google Scholar]). From these results it was thought possible that cutaneous antigen-antibody reactions might also release histamine in the sheep, and this possibility has been investigated in the present experiments.     

Pathogenicity of Enterococcus hirae for chicken embryos and betamethasone-treated chicks

An isolate Enterococcus hirae was used to determine its pathogenicity for chicken embryos and for chicks treated with betamethasone. E hirae was inoculated intravenously into four-day-old chicks which had been treated for three consecutive days with betamethasone, and chick embryos were inoculated into the allantoic cavity with 10² and 10³ bacteria. E hirae was not pathogenic for the chicks or for the embryos.     

Prevalence and Aetiology of Mastitis in Cows from Two Major Ethiopian Dairies

The study was undertaken to determine the aetiology and prevalence of mastitis in hand-milked cows (n = 186) in two major Ethiopian dairies. The California Mastitis Test and culturing for bacteria revealed that 21.5% of the cows were clinically infected and 38.2% had subclinical mastitis. Most mastitis pathogens isolated from milk samples testing positive by the California Mastitis Test were Gram-positive cocci. Staphylococci constituted 57% of the isolates, of which the predominant cause of bovine mastitis was Staphylococcus aureus (40.5%). Other mastitis pathogens isolated include streptococci (16.5%), coliforms (9%) and corynebacteria (5%). Retrospective analysis of farm records indicated that mastitis was the second most important cause of culling and accounted for 27% of the cows removed from these two dairies.     

The barnacle and the building: a modern morality tale

A rare and almost complete barnacle fossil, previously described on the basis of two isolated shell fragments, was recently exposed in a limestone block on the outer wall of Melbourne's Old Magistrates' Courts in Victoria, Australia. These courts comprise one of the oldest and grandest buildings in Melbourne and because of this they have a heritage listing. As heritage‐listed buildings are protected from alteration by law, and as removal of the fossil would be deemed “alteration”, official permission had to be obtained to extract the specimen. This paper discusses the processes involved with extraction of a unique specimen from a protected building and provides an overview of the palaeontological significance of the fossil. Consideration is given to the likely fate of a fossil of this nature, situated a little below eye level on a busy city street, if it was left in situ; finally, the implications of designating a holotype from material removed from a building are assessed.     

Pharmacokinetics of carbetocin,a long‐acting oxytocin analogue,following intravenous administration in horses

Reason for performing study: Current therapy protocols to treat persistent post mating endometritis and retained fetal membranes in mares typically include the administration of ecbolic drugs. Evaluation of the pharmacokinetics and tolerability of carbetocin, a long‐acting oxytocin analogue, after i.v. administration is required. Objectives: To determine the pharmacokinetic parameters (principally half‐life) of carbetocin in horses. Methods: Five mature mares and one gelding received 0.175 mg carbetocin i.v. All animals were monitored periodically throughout the study for elevation in rectal temperature, heart rate, respiratory rate and signs of pain or discomfort. Plasma samples were collected for determination of carbetocin concentrations by radioimmunoassay. Results: Administration of carbetocin was well tolerated by all horses and its half‐life was 17.2 min. Conclusions: The half‐life of carbetocin is greater than that previously reported for oxytocin (6.8 min). Potential relevance: Carbetocin is an attractive alternative to oxytocin therapy in broodmare management.     

Gastric carcinoma in a dog

An 8–year-old castrated male Bassett hound had been vomiting intermittently for 3 weeks. In addition, clinical signs of anorexia, weight loss, dehydration, depression and anterior abdominal pain were noted. Gastro-scopic and radiographic examination revealed a mass at the pyloric region of the stomach. Clinical remission followed surgical excision of gastric carcinoma, with recurrence of vomiting 4 months after surgery. At necropsy, the pyloric region of the stomach was markedly thickened, rigid, scirrhous and had an excavated ulcer. The pathological diagnosis was a poorly differentiated, diffuse gastric carcinoma with metastasis to regional lymph nodes.     

The pharmacokinetics of fenbendazole and oxfendazole in cattle

The pharmacokinetics of fenbendazole and oxfendazole in cattle are described. The pharmacokinetics of oxfendazole were not significantly different when administered orally and by intra-ruminal injection. At a dose rate of 4.5 mg/kg, administered orally, fenbendazole gave rise to mean peak concentrations in plasma of fenbendazole and oxfendazole of 0.11 and 0.13 g/ml respectively. Oral administration of oxfendazole, at 4.5 mg/kg body weight, gave rise to plasma peak concentrations of fenbendazole and oxfendazole of 0.10 and 0.20 g/ml respectively. Following intra-ruminal administration of oxfendazole, the peak concentrations were 0.11 and 0.18 g/ml respectively.