Assessment of the hemagglutinating activity of the Porcine
orthorubulavirus.
Abstract
Blue eye disease (BED) in pigs is caused by Porcine orthorubulavirus (P.
orthorubulavirus) of the Paramyxoviridae family. It is an endemic
disease in swine production in the central region of Mexico and causes
nervous signs and high mortality in suckling pigs, pneumonia in growing
pigs, orchitis in boars and mummification during gestation. P.
orthorubulavirus hemagglutinates most erythrocytes of domestic species.
For serological diagnosis, the hemagglutination inhibition test is used,
and in this test, guinea pig, bovine and chicken erythrocytes have been
commonly used. In this investigation, hemagglutination with P.
orthorubulavirus was evaluated using the erythrocytes of seven domestic
species (chicken, bovine, horse, pig, dog, guinea pig and rabbit). In
the hemagglutination test, the following parameters were evaluated:
temperature (25°C and 37°C), bottoms of the wells (V and U), erythrocyte
concentration (0.5, 0.75, and 1%), and reading time (15, 30, 45, 60 and
90 min). Significant differences (P < 0.001) were found in
most of the evaluated treatments. The best hemagglutination results were
obtained with chicken, bovine and horse erythrocytes. The
hemagglutination titer is higher (2 dilutions) when using chicken
erythrocytes than when using bovine or horse erythrocytes. If chicken
erythrocytes are used in the inhibition of hemagglutination, the test
will be more sensitive, while it is more specific when bovine or horse
erythrocytes are used. The hemagglutination readings are imprecise when
using erythrocytes from dogs, pigs, guinea pigs and rabbits.
Erythrocytes from these species should not be used for the diagnosis or
investigation of P. orthorubulavirus.