A lectin histochemical study of the thoracic respiratory air sacs of the fowl

Abstract

<span style="font-family: arial,helvetica;">The lectin-binding characteristics of the epithelial lining of the thoracic air sacs of the chicken were determined. Con A, LCA and PSA bound to the apical membrane as well as to the cytoplasm distal to the nucleus of the surface epithelium, indicated the presence of <span style="font-family: Symbol;" lang="AF"><span>a</span></span>-linked mannose as well as Nacetylchitobiose- linked <span style="font-family: Symbol;" lang="AF"><span>a</span></span>-fucose residues in the glycoproteins. GSL I bound to the apical membrane and cytoplasm distal to the nucleus, but not to the cilia of the epithelium, where-as MPL, DBA and RCA120 bound to the apical membrane, cilia and cytoplasm, indicated the presence of <span style="font-family: Symbol;" lang="AF"><span>a</span></span>-linked Nacetylgalactosamine residues. However, neither SJA or SBA showed any binding, indicating the absence of <span style="font-family: Symbol;" lang="AF"><span>b</span></span> anomers of galactosyl (<span style="font-family: Symbol;" lang="AF"><span>b</span></span>1.3)N-acetylgalactosamine and <span style="font-family: Symbol;" lang="AF"><span>b</span></span>-linked N-acetylgalactosamine residues. UEA I bound to the apical membrane and cilia, as well as to the cytoplasm of a few cells, indicated the presence of <span style="font-family: Symbol;" lang="AF"><span>a</span></span>-linked fucose residues. PNA bound to the apical membrane of some, but not all, surface epithelium cells, indicated the presence of galactosyl (<span style="font-family: Symbol;" lang="AF"><span>b</span></span>1.3)N-acetylgalactosamine residues. WGA bound to the apical membrane and cilia, as well as to the cytoplasm of a few cells, indicated the presence of neuraminic acid residues.</span&gt

Three‐Dimensional Serial Section Computer Reconstruction of the Arrangement of the Structural Components of the Parabronchus of the Ostrich, Struthio Camelus Lung

“…Its massspecific resting oxygen consumption (Vo 2 ) is about 30% higher than that predicted from its body mass (King and Farner, 1969;Schmidt-Nielsen et al, 1969). The high aerobic capacity of the Ostrich is made possible by a particularly specialized respiratory system (Schmidt-Nielsen et al, 1969;Jones, 1982;Bezuidenhout et al, 1999;Maina and Nathaniel, 2001). The air sacs are well developed (Schmidt-Nielsen et al, 1969;Bezuidenhout et al, 1999).…”

“…The high aerobic capacity of the Ostrich is made possible by a particularly specialized respiratory system (Schmidt-Nielsen et al, 1969;Jones, 1982;Bezuidenhout et al, 1999;Maina and Nathaniel, 2001). The air sacs are well developed (Schmidt-Nielsen et al, 1969;Bezuidenhout et al, 1999). Its total anatomical pulmonary diffusing capacity for oxygen (DLo 2 ) exceeds those of relatively smaller volant birds .…”

Evaluation of respiratory route as a viable portal of entry for Salmonella in poultry

“…Part of the reason for this may be that the air sacs extend well beyond the limits of the coelomic cavity, with many bones being extensively pneumatized. 125,126 A key explanation regarding the susceptibility of caudal air sacs to infection lies in the gas flow pathway and the mechanisms present in the parabronchi for particle removal. Due to the arrangement of the parabronchi, avian lungs have a flowthrough system of breathing, unlike the tidally ventilated mammalian respiratory system.…”

Cellular Defences of the Lung: Comparative Perspectives

“…Maina et al, 1989), b) large tidal volume and continuous and unidirectional ventilation of the lung (e.g. Fedde 1980Fedde , 1997Brown et al, 1997), and c) in some species, e.g., the ostrich, Struthio camelus (Bezuidenhout et al, 2000), the air sacs extend out of the coelomic cavity to lie subcutaneously, where they are highly susceptible to trauma and infection: in such cases, air sacculitis (infection of the air sacs) can easily spread to the lung.Categorical proof that the avian lung is relatively more susceptible to infection by inhaled biological pathogens is lacking. It was argued by Maina (2005) that in the bird lung, PSMs, cells that are abundantly endowed with lysosomes (Nganpiep and Maina 2002) (Fig.…”