ABSTRACT
1. Hatching chicks were exposed to 10.9 ppm of formaldehyde vapour during the last 3 d of incubation in a commercial situation. 2. Samples from pre-selected regions of the entire respiratory tract, taken at 0, 6, 30 and 54 h post-vaporisation of formaldehyde, were examined by scanning electron microscopy for surface morphological features and associated pathological changes. 3. Clumping of cilia, blebs on the cilial wall, deciliation and exfoliation of the epithelium were all observed under the scanning electron microscope. 4. Lesions were more severe in chicks exposed for 54 h as compared to those exposed for 6 and 30 h. There were no regional differences in the lesions throughout the respiratory tract of all the chicks. 5. Limited observations suggest that the passage of formaldehyde vapour across the egg shell wall may influence the morphology of the respiratory lining of the developing embryo.
Subject(s)
Formaldehyde , Fumigation/adverse effects , Respiratory System/pathology , Animals , Chick Embryo , Chickens , Cilia/drug effects , Cilia/pathology , Cilia/ultrastructure , Epithelium/drug effects , Epithelium/pathology , Epithelium/ultrastructure , Microscopy, Electron, Scanning , Respiratory System/drug effects , Respiratory System/ultrastructureABSTRACT
The relative scarcity of primary and secondary skin infections in birds depends, at least in part, on the functional morphological barrier presented by the avian integument. Both transmission and scanning electron microscopical techniques were used to study the ultrastructural morphology of the epidermal barrier in the cere of the domestic racing pigeon. The epidermis is composed of sebokeratocytes which are responsible for producing not only the keratin proteins of the keratinized stratum corneum, but also the lipid emulsion forming the surface lipid layer and filling the intercellular spaces. The possible importance and role of these components in the defensive barrier presented by the skin is discussed.
Subject(s)
Columbidae/anatomy & histology , Animals , Basement Membrane/ultrastructure , Epidermis/ultrastructure , Microscopy, Electron , Microscopy, Electron, Scanning , Skin/ultrastructureABSTRACT
Ultrastructural studies of the perisinusoidal space in the avian liver have demonstrated the presence of 2 extravascular cell types--a fat-storing cell and a free mesenchyme cell or histiocyte. This latter cell type is capable of participating in the formation of a bile canaliculus with the hepatic parenchymal cell. The possibility of the fat-storing cell differentiating from the histiocyte is suggested.