Pharmacological basis of immediate hypersensitivity in the domestic fowl: a review

This review discusses the mechanisms of immediate hypersensitivity and their putative relationship to clinical syndromes in the fowl. The general features of these mechanisms are outlined, in terms of the pharmacological mediators involved, the anaphylactic antibodies, and the distribution and relative significance of the immune target cells — the mast cells and basophils. Emphasis is given to the ways in which these features are similar to or differ from those occurring in mammals. Consideration is given to the immunological release of histamine and of SRS-A in the fowl. The results of work on the mechanisms of in vitro anaphylaxis (Schultz-Dale phenomenon) in the chicken are discussed. The roles of several potential mediators of acute systemic anaphylaxis are discussed in some detail, with reference to the activities of antagonists to each of these potential mediators. A major role for the vasoactive lipids and peptides is suggested.     

Arsenates: Effect on Fecundity in Some Diptera

Four species of adult Diptera, Rhagoletis pomonella (Walsh), Drosophila melanogaster Mg., Drosophila hydei Sturt., and Musca domestica L. showed varying degrees of reduced fecundity when sublethal doses of arsenic were included in their food. The possible influence of the frequent use of arsenicals on arthropod populations is discussed.     

TREATMENT OF DIAPHRAGMATIC HERNIA IN BUFFALOES

The surgical treatment of diaphragmatic hernia attempted on 19 lactating buffaloes is described. Thirteen cases recovered uneventfully, 1 recovered after developing brisket oedema and 5 died, 3 during surgery and 2 postoperatively. The desired depth of anaesthesia was achieved by the administration of 6% chloral hydrate followed by 5% thiopentone sodium. A postxiphoid approach and the use of a continuous lock stitch suture were preferred to repair the vent in the diaphragm. Pre- and post-operative use of hydrocortisones and fluids and sufficient tissue oxygenation by controlled positive pressure respiration are believed to be keys to the success of the treatment adopted.     

ACTINOMYCIN: INHIBITION OF CORTISONE-INDUCED SYNTHESIS OF HEPATIC GLUCONEOGENIC ENZYMES

The cortisone-induced de novo synthesis of liver glucose-6-phosphatase, fructose-1, 6-diphosphatase, aldolase, and lactic dehydrogenase was prevented by injections of Actinomycin D in the rat. In the in vitro assay systems, addition of actinomycin exerted no effect on the enzyme activities examined. The evidence favors the concept that the increased gluconeogenesis induced by corticoids entails at a certain stage an increased rate in the synthesis of gluconeogenic enzymes.     

Equine Protozoal Myeloencephalitis: A Report of Two Cases From Western Canada

Two cases of nonsuppurative myeloencephalitis are reported which clinically and pathologically resemble equine protozoal myeloencephalitis. Lesions in both horses were associated with Toxoplasma-like organisms visible in microscopic sections. Clinical signs and lesions in one case primarily involved the brain and in the other case principally involved the spinal cord and associated meninges. Positive identification of the organisms was not achieved; however, the etiological agent is unlikely to be a species of Toxoplasma. Recently published studies suggest a species of Sarcocystis is involved.     

Early body weight of five strains of White Leghorn.

1. The means, standard errors and coefficients of variation for body weight at fortnightly intervals from day 1 to day 90 of five indigenous strains of White Leghorn were estimated. 2. The differences between the strain and body weight were significant at all ages while the differences between sex were significant from day 45. 3. Phenotypic correlations between body weight at day 1 with that of day 30, 60 and 90 were 0-237, -0-007 and -0.07. 4. The heritability by paternal half-sib method ranged from 0-32 to 0-54 for body weights from day 1 to day 90.