Serotyping, Genotyping and Virulence Genes Characterization of Pasteurella multocida and Mannheimia haemolytica Isolates Recovered from Pneumonic Cattle Calves in North Upper Egypt

Abstract

Pasteurella (P.) multocida and Mannheimia (M.) haemolytica are the most two common pathogenic bacterial agents causing pneumonia in calves. Both bacteria are associated with significant economic losses in the cattle industry due to high morbidity and mortality rates, especially in the case of severe infections. The objectives of the present study were to perform serotyping and genotyping, as well as characterization of the virulence-associated genes in 48 bacterial isolates; 33 P. multocida and 15 M. haemolytica. All strains were isolated from pneumonic cattle calves showing respiratory manifestations such as fever, nasal discharges, and rapid breathing in North Upper Egypt governorates (Beni-Suef and El-Fayoum). PCR was applied as a confirmatory test using a specific universal gene, kmt1, and rpt2 for P. multocida and M. haemolytica, respectively. The results show that 29 (87.9%) P. multocida and 15 (100%) M. haemolytica isolates were positive for the corresponding universal gene. The results of serotyping indicate that 86.2% of P. multocida isolates belonged to serotype B:2, while 13.8% were untyped. Meanwhile, 60% and 40% of M. haemolytica isolates belonged to serotype 2 and serotype 1, respectively. Investigation of virulence-associated genes showed that all the tested P. multocida isolates harbored nanB, omp87, and toxA genes. Four M. haemolytica isolates harbored both gcp and lktC genes and of these, three isolates harbored the ssa gene. Sequencing of toxA gene of P. multocida and lktC gene of M. haemolytica in the current strains indicated a great homology with strains uploaded in gene banks from different hosts and localities worldwide.

Prevalence and Molecular Characterization of Mycoplasma Species, Pasteurella multocida, and Staphylococcus aureus Isolated from Calves with Respiratory Manifestations

“…Mycoplasma infection is a serious problem in small ruminants in Egypt, among both healthy animals or animals with respiratory signs [42]. P. multocida and M. haemolytica are the most common pathogens causing pneumonia in calves in upper Egypt, reaching 87-100% in some farms [20]. The mixed infection of both P. multocida and M. haemolytica with S. aureus was prevalent among calves in several farms in Upper and Middle Egypt [21].…”

“…Our study corroborates several studies in Egypt that employed PCR for rapid detection of the bacterial species recovered from respiratory manifestation in young calves. For example, Abed and colleagues applied PCR as a confirmatory test to identify P. multocida using a specific universal gene (kmt1) from pneumonic calves in Upper Egypt [20]. A recent study recommended PCR as the principal molecular technique for detecting Mycoplasma spp.…”

“…The government has also developed plans to increase commercial dairy and beef farming in the new cities near the desert all over the country. However, outbreaks of diseases, particularly respiratory infections considerably dented the success of cattle farming in Egypt [14,[19][20][21][22]. As respiratory infections incur severe economic losses and fatal complications in young calves due to pneumonia, this study aimed to determine the prevalence, molecular characterization, and sequencing analysis of the most common bacterial pathogens associated with the respiratory manifestations in young calves in Sadat City, one of the most important cities targeted for reclamation and animal production sectors by the government in Egypt.…”

Serotyping, antibiogram, and detection of bacterial pathogens associated with bovine respiratory disease in selected areas of Ethiopia

“…On the other hand, four serotypes (3, 4, 10, and 15) are worth mentioned as B. trehalosi that belong to biotype T [11]. Serotype A:11 was later reclassified as M. glucosidal [12]. P. multocida strains are currently classified into five capsular types or serogroups (A, B, D, E, and F) based on capsular polysaccharide and into 16 Heddleston lipopolysaccharides (LPS) serovars using the gel diffusion precipitation assay [13,14].…”

Review on Pasteurellosis: Causes, Pathogenesis, Diagnosis and Current Status in Ethiopia

“…A variety of etiologic agent form this multi-factorial disease such as Pasteurella multocida (P. multocida) (P. multocida gallicida, P. multocida multocida) and P. multocida septica. may also be divided into five capsular serogroups (A-E) and sixteen somatic serotypes [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Mannheimia haemolytica (M. haemolytica) formerly named P. haemolytica has two biotypes A and T depending on arabinose and trehalose fermentation.…”