The blood volumes and erythrokinetics of Ndama and Zebu cattle experimentally infected with Trypanosoma brucei.

The responses of susceptible Ndama and Zebu cattle to experimental infection with Trypanosoma brucei were compared using haematological, parasitological and radioisotopic methods. Animals of both breeds became anaemic, but this was more severe in the Zebu cattle, one of which died. Although the prepatent period was the same in animals of both breeds, the levels of the first and subsequent peaks of parasitaemia were higher in the Zebu. The anaemia was due to an accelerated rate of red cell break-down which was more marked in the Zebu cattle. Haemodilution was not a feature. There was no evidence of dyshaemopoiesis but iron reutilisation from degraded erythrocytes was impaired. The greater resistance of the Ndama to T brucei infection could not be attributed to the capacity of this breed to mount a more effective erythropoietic response than the Zebu.     

Tissue reaction to Cysticercus bovis in the lung of artificially infected cattle

The tissue reaction to Cysticercus bovis in the lung of cattle with an experimental infection was an inflammatory rim originating in the immediate vicinity of the cysts. The cysts recovered at days 83 and 102 p.i. contained living cysticerci. The rim was composed either of a layer of high histiocytes organized in palisades (at day 83 p.i.), or a lyer of flat histiocytes (at day 102 p.i.). The outer layer of the rim consisted of fibroblasts, reticular cells and a different number of eosinophil- and neutrophil luekocytes. On the periphery, the rim was formed by granulation tissue infiltrated with lymphoplasmocytes. At the border between the layers of the inflammatory rim there were conspicuous foci of a necrotic appearance typical of a tissue reaction to C. bovis.     

Monellia costalis (Fitch), a new host forZoophthora radicans (Brefeld) Batko andEntomophthora Planchoniana Cornu (Zygomycetes: Entomophthoraceae) in Israel

Two entomophthoraceous species,Zoophthora radicans andEntomophthora planchoniana, were found on the yellow pecan aphid,Monellia costalis, shortly after it was introduced into Israel. This aphid is a new host forZ. radicans anywhere. The fungus was isolated in pure culture and artificially inoculated on three Dipteran species:Musca domestica, Drosophila melanogaster andCeratitis capitata, as well as on the HemipteranEmpoasca sp. from pecan. The identity ofZ. radicans and some new characters,e.g. the production of two kinds of rhizoids, are discussed. The possibility of usingM. domestica as a vector for artificial spread of the fungus, as a means of biological control of various insect pests, is advocated.     

Lack of effect of dietary ascorbic acid on stability of carcass fat and meat of broilers 1

1. The inclusion of ascorbic acid or ascorbyl palmitate in a diet containing soyabean oil (40 g/kg) and butylated hydroxytoluene (25 mg/kg) did not affect the stability of abdominal fat and meat of broilers.

2. Under the same conditions including α‐tocopheryl acetate or ethoxyquin significantly improved the stability of these tissues.     

Tiering in suspension-feeding communities on soft substrata throughout the phanerozoic

Tiering of benthic marine suspension-feeding communities on soft substrata has varied throughout the Phanerozoic. Epifaunal tiering was most developed during the middle and late Paleozoic and the Triassic to Jurassic, with large-scale reductions in tiering occurring during the Permian-Triassic extinctions and after the Jurassic. Infaunal tiering reached its highest level of organization after the Paleozoic.     

Scanning electron microscope study of the feather follicle wall attachment in chickens

1. A scanning electron microscope study showed indentations by the follicle wall cells into the feather shaft. In other areas altered cells or keratinised cell fragments form bridges which join the feather to the follicle.

2. In the early stage of growth the feather shaft is held in place by cell indentations, whereas later, bridges are seen which probably hold the feather more firmly.