Search Results

You are looking at 1 - 2 of 2 items for

  • Author or Editor: K. René Simons x
  • Refine by Access: All Content x
Clear All Modify Search

SUMMARY

Four colostrum-deprived calves each were immunized passively with antisera to whole Pasteurella haemolytica, leukotoxin-containing supernatants of P haemolytica, P haemolytica lipopolysaccharide, or newborn calf serum. Calves were challenge exposed intrabronchially with 5 × 109 P haemolytica, and 24 hours later, the resulting lesions were evaluated. The greatest protection against challenge exposure was provided by the antiserum to whole P haemolytica (lesion score = 6.3), whereas newborn calf serum provided the least protection (lesion score = 28.3). Calves that received antiserum to P haemolytica supernatants were moderately protected (lesion score = 16.3), and the antiserum to lipopolysaccharide provided minimal protection (lesion score = 21.8). Antibodies that were unique to whole P haemolytica antiserum and produced dense bands on immunoblots were detected to antigens at 66, 50, and 30 kd. Antibodies in the supernatant preparation that produced prominent bands reacted to antigens between 100 and 90 kd. Collectively, antibodies to these antigens may be responsible for enhancing resistance to experimentally induced pneumonic pasteurellosis. Antibodies to antigens in P haemolytica lipopolysaccharide provided little to no protection.

Free access
in American Journal of Veterinary Research

Summary

Supernatant preparations containing antigens produced by Pasteurella haemolytica serotype 1 grown in nonsupplemented RPMI 1640 medium and 3 grown in supplemented RPMI 1640 media were evaluated. Antigens were detected by immunoblotting each supernatant preparation with sera from 20 cattle with various degrees of resistance to experimentally induced pneumonic pasteurellosis. Antigen antibody bands at 49 and 30 kd were correlated with resistance in all 4 media. A 66-kd antigen-antibody band was correlated with resistance in 2 media, and antigen-antibody bands at 100 and 16 kd were correlated with resistance in 1 medium each. These results indicated that the number and relative amount of resistance-associated antigens in P haemolytica supernatants can be optimized on the basis of type of growth medium used.

Free access
in American Journal of Veterinary Research