Effect of experimental Mannheimia haemolytica [Pasteurella haemolytica] infection in sheep fed colostrum and dam or cow milk after birth on serum IgG.

摘要

The objective of this study was to determine the effect of experimental Mannheimia haemolytica [Pasteurella haemolytica] infection in sheep fed colostrum and ewe or cow milk after birth on the serum IgG levels. 10 Chios newborn lambs were fed ad libitum with colostrum and ewe milk (control group). Another 10 lambs were separated from their dams immediately. These lambs were unallowed to suckle normally but were fed with cow milk using a feeding bottle (experimental group). When the sheep were one-year-old, the study was continued. The animals were inoculated intratracheally with 1x109 log-phase M. haemolytica. Blood samples were collected from the jugular vein once before bacterial inoculation and on days one, 4, 7, 10, 13, 16, 19 and 22 after the inoculation. Antibiotic treatment was applied on day 22. Blood samples were also collected on days one, 4 and 7 after the treatment. IgG levels were significantly higher in the control group than in the experimental group on days zero, one, 4, 7, 10, 13, 16, 19 and on day one after treatment. The levels in the control group gradually decreased. Results suggested that the lambs non-sucking their dams might suffer, as one-year-old sheep, from an insufficiency of the immune system, and that the sheep compensated this disorder with its own immune system..