Immunogenicity of the lipid A component of Haemophilus somnus lipooligosaccharide in cattle and mice was examined after purification, detoxification, and covalent conjugation to a protein carrier. After 2 inoculations, a substantial antibody response was induced in most cattle to lipid A and the protein carrier. To determine whether antibodies to lipid A would be protective, 5 X 10(7) colony-forming units of H somnus strain 649 were administered IV to endotoxin-responsive (C3H/HEN) mice. In one study, 8 of 13 C3H/HEN mice aborted when inoculated. In contrast, abortion did not result when mice were inoculated with the same dose of an isolate of H somnus normally found in the prepuce or with the rough mutant Escherichia coli J5. In addition, endotoxin-nonresponsive (C3H/HeJ) mice were significantly (P = 0.03) more resistant to abortion by strain 649 than were C3H/HeN mice, but inoculated C3H/HeN mice were only slightly more resistant to H somnus abortion, compared with control mice. Although a large antibody response to lipid A was detected, there was no significant difference in the immunized group between mice that aborted and mice that delivered normally. Thus, lipooligosaccharide and other properties of virulent H somnus strains may contribute to abortion in mice.

Q fever is a zoonotic disease that occurs worldwide and is caused by the obligate intracellular bacterium Coxiella burnetii. The aim of this study was to investigate the presence of C. burnetii infection in aborted sheep in eastern Turkey using PCR. A total of 200 fetuses were collected from aborted sheep belonging to 200 herds in different locations in the eastern part of Turkey. Foetal organ samples such as liver, spleen, lung and stomach were taken and the DNA was purified from two hundred pooled samples. PCR analysis of C. burnetii presence in infected organs was performed, and 4 samples (2%) were found positive. In addition, the pooled organ suspensions were inoculated to embryonated chicken eggs, and PCR analysis of yolk sacs showed C. burnetii DNA in 5 samples (2.5%). This study shows that C. burnetii infection has an important role in sheep abortions in eastern Anatolia region.

Q fever is a zoonotic disease that occurs worldwide and is caused by the obligate intracellular bacterium Coxiella burnetii. The aim of this study was to investigate the presence of C. burnetii infection in aborted sheep in eastern Turkey using PCR. A total of 200 fetuses were collected from aborted sheep belonging to 200 herds in different locations in the eastern part of Turkey. Foetal organ samples such as liver, spleen, lung and stomach were taken and the DNA was purified from two hundred pooled samples. PCR analysis of C. burnetii presence in infected organs was performed, and 4 samples (2%) were found positive. In addition, the pooled organ suspensions were inoculated to embryonated chicken eggs, and PCR analysis of yolk sacs showed C. burnetii DNA in 5 samples (2.5%). This study shows that C. burnetii infection has an important role in sheep abortions in eastern Anatolia region.