Proliferation of Pasteurella haemolytica serotype 1 in the nasal cavit
y following stress or viral infection is an important event in the pat
hogenesis of bovine pneumonic pasteurellosis. Enhanced adhesion of P.
haemolytica to nasal mucosa could be one factor that predisposes anima
ls to this proliferation. Nasal mucosa from normal and bovine herpesvi
rus-1 (BHV1)-infected cattle were examined histochemically for their g
lycoconjugate composition. Twenty lectins were screened, six of which
were chosen for subsequent study. Three of these were specific for N-a
cetylgalactosamine (NAGal) (Dolichos biflorus, Glycine max, and Vicia
villosa), and one each was specific for N-acetylgalactosamine/galactos
e (Griffonia simplicifolia-I), mannose/glucose (Canavalia ensiformis),
and N-acetylglucosamine (Triticum vulgaris). For the surface mucosa a
nd submucosal glands, there was greater reactivity in samples from BHV
1-infected than from normal cattle for all six lectins. Reactivity was
most prominent for the NAGal-specific lectins. Neuraminidase treatmen
t of samples from normal and BHV1-infected cattle tended to result in
greater lectin reactivity. Lectin reactivity was generally more intens
e in focally inflamed areas, but diffuse reactivity was not substantia
lly affected by inflammation. BHV1-induced alteration of nasal mucosal
glycoconjugates could enhance adhesion and colonization of P. haemoly
tica to nasal surfaces and may be one factor responsible for the incre
ased number of P. haemolytica serotype 1 in the nasal cavity following
viral infection.