Epidemiology of Ovine Pasteurellosis in Lume District, East Shewa Zone of Oromiya Region, Ethiopia

Open Access Journal of Veterinary Science & Research ISSN: 2474 - 92 22 Epidemiology of Ovine Pasteurellosis in Lume District, East Shewa Zone of Oromiya Region, Ethiopia J Vet Sci Res Epidemiology of Ovine Pasteurellosis in Lume District, East Shewa Zone of Oromiya Region, Ethiopia Sadia H 1 , Abunna F 2 and Jarso D 2 * 1 Oromia Livestock and Fishery Resource Development Bureau, Addis Ababa, Ethiopia 2 Department of Veterinary Medicine and Agriculture, Addis Ababa University, Ethiopia *Corresponding author: Jarso D, Department of Veterinary Medicine and Agriculture, Addis Ababa University, Ethiopia, E - mail: [email protected] Abstract The study of ovine pasteurellosis was conducted in Lume districts, East Shoa Zone of Oromia region, Ethiopia to determine the prevalence of M annheimia haemolytica , Pasteurella trehalosi and Pasteurella multocida from nasal swabs (384), abattoir specimens (145 ), and the serotype diversity among the species from sheep sera (150). A total of 115 isolates of M. haemolytica , P. treha losi and P. multocida were isolated from nasal swabs of apparently health and clinically sick sheep and from pneumonic lungs. The M. haemolytica, P. trehalosi and Pasteurella multocida were isolated from the nasal swabs (11.2%), (7.6%) and (2.1) respective ly, whereas M. haemolytica and P. trehalosi were isolated from pneumonic lungs (11.7%) , ( 10.3 ) respectively. However, Pasteurella multocida was the lowest among species isolated (2.1%). The overall isolation rate of M. haemolytica, P. trehalosi and Pasteurella multocida was 15.7%, 11.5% and 2.9%, respectively. From 145 lung samples collected and cultured, Pasteurella was isolated successfully in 35 (24.1%) sheep. Out of 35 sheep lung lesion sample, the percentage recovery rate of M. haemolytica 17(11 .7%), P. trehalose 15(10.3%) and P. multocida 3(2.1) % respectively. On the basis of these results, M. haemolytica and P.trehalose were the most common cause of pasteurellosis in sheep at the study area. A total of 150 sheep sera were examined for serotype specific antibodies using indirect haemagglutination test for M. haemolytica, P. trehalose and P. multocida serotypes. Variation in prevalence among the different serotypes was observed (P<0.001). The IHA test revealed that serotype A1, A2, A7, T3, T10, a nd T15 were the dominant serotypes with 23.3%, 42.6%, 32, 51.3, 29.3 and 30% positive by IHA whereas serotypes P. multocida biotype A and T4 were the least positive with 14.6% and16% respectively. Generally, both bacterial and serological results of this s tudy revealed that the causal agents of pasteurellosis are prevalent in the area, and serotypes A1, A2, A7, T3, T10 and T15 were dominant over the other serotypes

Subcutaneous Botryomycosis Due to Bibersteinia trehalosi in a Texas Longhorn Steer

A 3-year-old Texas Longhorn steer had a long history of progressive swelling of the soft tissues of the jaw and neck. At necropsy, multifocal to coalescing dermal and subcutaneous pyogranulomas were surrounded by fibrous tissue. Microscopically, the pyogranulomas contained aggregates of gram-negative coccobacilli surrounded by Splendore-Hoeppli material and were separated by bands of fibrovascular tissue (botryomycosis). Phylogenetic analysis of multilocus sequence-typing data revealed that the bacteria recovered in pure culture from swabs of submandibular tissue were most closely related to Bibersteinia [ Pasteurella] trehalosi. The bacterial colonies were immunohistochemically reactive with a rabbit polyclonal anti-Pasteurella class C acid phosphatase antibody. Botryomycosis is a pyogranulomatous inflammation caused by a variety of nonbranching, nonfilamentous bacteria that elicit the formation of Splendore-Hoeppli material. This case of botryomycosis is unique for its association with Bibersteinia trehalosi.

Sequence Diversity and Molecular Evolution of the Heat-Modifiable Outer Membrane Protein Gene (ompA) of Mannheimia(Pasteurella) haemolytica, Mannheimia glucosida, and Pasteurella trehalosi

ABSTRACT The OmpA (or heat-modifiable) protein is a major structural component of the outer membranes of gram-negative bacteria. The protein contains eight membrane-traversing β-strands and four surface-exposed loops. The genetic diversity and molecular evolution of OmpA were investigated in 31 Mannheimia (Pasteurella) haemolytica, 6 Mannheimia glucosida, and 4 Pasteurella trehalosi strains by comparative nucleotide sequence analysis. The OmpA proteins of M. haemolytica and M. glucosida contain four hypervariable domains located at the distal ends of the surface-exposed loops. The hypervariable domains of OmpA proteins from bovine and ovine M. haemolytica isolates are very different but are highly conserved among strains from each of these two host species. Fourteen different alleles representing four distinct phylogenetic classes, classes I to IV, were identified in M. haemolytica and M. glucosida. Class I, II, and IV alleles were associated with bovine M. haemolytica, ovine M. haemolytica, and M. glucosida strains, respectively, whereas class III alleles were present in certain M. haemolytica and M. glucosida isolates. Class I and II alleles were associated with divergent lineages of bovine and ovine M. haemolytica strains, respectively, indicating a history of horizontal DNA transfer and assortative (entire gene) recombination. Class III alleles have mosaic structures and were derived by horizontal DNA transfer and intragenic recombination. Our findings suggest that OmpA is under strong selective pressure from the host species and that it plays an important role in host adaptation. It is proposed that the OmpA protein of M. haemolytica acts as a ligand and is involved in binding to specific host cell receptor molecules in cattle and sheep. P. trehalosi expresses two OmpA homologs that are encoded by different tandemly arranged ompA genes. The P. trehalosi ompA genes are highly diverged from those of M. haemolytica and M. glucosida, and evidence is presented to suggest that at least one of these genes was acquired by horizontal DNA transfer.