Responses of pro-inflammatory cytokines, acute phase proteins and cytological analysis in serum and cerebrospinal fluid during haemorrhagic septicaemia infection in buffaloes.

Sudden death is usually the main finding in field animals during haemorrhagic septicaemia outbreaks caused by Pasteurella multocida type B:2 that causes acute, fatal and septicaemic disease in cattle and buffaloes. This situation may be due to failure in early detection of the disease where early treatment of antibiotics may improve the prognosis of the animal and other surviving animals. Thus, there is a grey area on the knowledge on the potential usage of pro-inflammatory cytokines and acute phase proteins as early biomarkers in the diagnosis of haemorrhagic septicaemia. In addition, exploration of the cerebrospinal fluid during infection has never been studied before. Therefore, this study was designed to fill up the grey areas in haemorrhagic septicaemia research. Twenty-one buffalo calves were divided into seven treatment groups where group 1 was inoculated orally with 10 mL of sterile phosphate-buffered saline pH 7 which act as a negative control group. Groups 2 and 3 were inoculated orally and subcutaneously with 10 mL of 1012 colony-forming unit of P. multocida type B:2. Group 4 and 5 buffaloes were inoculated orally and intravenously with 10 mL of lipopolysaccharide broth. Groups 6 and 7 were administered orally and subcutaneously with 10 mL of outer membrane protein broth. During the post-infection period of 21 days, blood and cerebrospinal fluid were sampled for the analyses of pro-inflammatory cytokines, acute phase proteins and cytological examination. Buffalo calves infected with P. multocida and its immunogens via different routes of inoculation showed significant changes (p < 0.05) of pro-inflammatory cytokines, acute phase proteins and cytological changes in both the serum and cerebrospinal fluid. Buffalo calves from groups 3 and 7 showed the highest pro-inflammatory cytokines, whereas group 6 had the highest acute phase protein concentration and group 5 revealed the highest value for cytology changes. In summary, results obtained in this study could be used as a profiling study to add novel knowledge to the haemorrhagic septicaemia research as well as the development of biomarkers.

Reproductive hormonal variations and adenohypophyseal lesions in pre-pubertal buffalo heifers inoculated with Pasteurella multocida type B: 2 and its immunogens.

BACKGROUND: Hemorrhagic septicemia is a fatal disease of cattle and buffaloes caused by P. multocida. Although the pathogenesis of the bacteria has been well established in literature, there is a paucity of information on the possible role of the bacteria and its immunogens; lipopolysaccharide (LPS) and outer membrane proteins (OMPs) on the reproductive capacity of buffalo heifers. METHODS: In this study, twenty one healthy prepubertal female buffaloes aged 8 months were divided into seven groups of 3 buffaloes each (G1-G7). Group 1 (G1) served as the negative control group and were inoculated orally with 10 mL sterile Phosphate Buffer Saline (PBS), groups 2 (G2) and 3 (G3) were inoculated orally and subcutaneously with 10 mL of 1012 colony forming unit (cfu) of P.multocida type B: 2, while groups 4 (G4) and 5 (G5) received 10 mL of bacterial LPS orally and intravenously, respectively. Lastly, groups 6 (G6) and 7 (G7) were orally and subcutaneously inoculated with 10 mL of bacterial OMPs. Whole blood was collected in EDTA vials at stipulated time points (0, 2, 4, 6, 8, 10, 12, 24, 36, 48, 72, 120, 168, 216, 264, 312, 360, 408, 456 and 504 h), while tissue sections of the pituitary glands were collected and transported to the histopathology laboratory in 10% buffered formalin for processing and Hematoxylin and eosin staining. Plasma levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), progesterone (PG), estradiol (EST) and gonadotrophin releasing hormone (GnRH) were determined. RESULTS: The histopathological lesions observed in the pituitary gland included hemorrhage, congestion, inflammatory cell infiltration, hydropic degeneration, necrosis and edema. These changes were higher (p < 0.05) in distribution and severity in G3, G6 and G7. Hormonal concentrations of LH, FSH, PG, EST and GnRH declined in all inoculation groups as time elapsed and were lower (p < 0.05) than that of the control group. CONCLUSION: Based on these findings, P.multocida B: 2 and its immunogens can be said to negatively affect the hypothalamic-pituitary-gonadal axis, resulting in decreased levels of reproductive hormones which may predispose to infertility in buffalo heifers.

The ability of lipopolysaccharide (LPS) of Pasteurella multocida B:2 to induce clinical and pathological lesions in the nervous system of buffalo calves following experimental inoculation.

Lipopolysaccharide (LPS) of P. multocida B:2, a causative agent of haemorrhagic septicaemia (HS) in cattle and buffaloes, is considered as the main virulence factor and contribute in the pathogenesis of the disease. Recent studies provided evidences about the involvement of the nervous system in pathogenesis of HS. However, the role of P. multocida B:2 immunogens, especially the LPS is still uncovered. Therefore, this study was designed to investigate the role of P. multocida B:2 LPS to induce pathological changes in the nervous system. Nine eight-month-old, clinically healthy buffalo calves were used and distributed into three groups. Calves of Group 1 and 2 were inoculated orally and intravenously with 10 ml of LPS broth extract represent 1 × 1012 cfu/ml of P. multocida B:2, respectively, while calves of Group 3 were inoculated orally with 10 ml of phosphate buffer saline as a control. Significant differences were found in the mean scores for clinical signs, post mortem and histopathological changes especially in Group 2, which mainly affect different anatomic regions of the nervous system, mainly the brain. On the other hand, lower scores have been recorded for clinical signs, gross and histopathological changes in Group 1. These results provide for the first time strong evidence about the ability of P. multocida B:2 LPS to cross the blood brain barrier and induce pathological changes in the nervous system of the affected buffalo calves.

Clinico-pathology and hemato-biochemistry responses in buffaloes infected with Pasteurella multocida type B:2 immunogen outer membrane protein.

The aim of this study was to investigate the clinico-pathology and haemato-biochemistry alterations in buffaloes inoculated with Pasteurella multocida type B:2 immunogen outer membrane protein via subcutaneous and oral routes. Nine buffalo heifers were divided equally into 3 treatment groups. Group 1 was inoculated orally with 10 mL of phosphate buffer saline (PBS); Group 2 and 3 were inoculated with 10 mL of outer membrane protein broth subcutaneously and orally respectively. Group 2 buffaloes showed typical haemorrhagic septicaemia clinical signs and were only able to survive for 72 h of the experiment. However, Group 3 buffaloes were able to survive throughout the stipulated time of 21 days of experiment. There were significant differences (p < 0.05) in the rectal temperature between the experimental and control group. In the hematology and biochemistry findings, there were significant differences (p < 0.05) in packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin concentration, leukocytes, band neutrophils, segmented neutrophils, lymphocytes, eosinophils, basophils, gamma glutamyl transferase, total protein, and globulin between Group 2 and control group. In contrast, Group 3 and control group revealed significant differences (p < 0.05) in erythrocytes, haemoglobin, mean corpuscular haemoglobin concentration, segmented neutrophils, lymphocytes, monocytes, eosinophils, basophils, thrombocytes, gamma glutamyl transferase, total protein, globulin, and albumin:globulin ratio. In Group 2 buffaloes, there were gross lesions observed in the lung, trachea, heart, liver, spleen, kidney and submandibulae lymph nodes. In contrast, lesions were only observed in the lung, and liver of Group 3 buffaloes. There were significant differences (p < 0.05) in hemorrhage and congestion; necrosis and degeneration; and inflammatory cells infiltration between experimental groups and control group. However, there were no significant differences (p > 0.05) in edema between groups except for the lung. This study was a proof that oral route infection of Pasteurella multocida type B:2 immunogen outer membrane protein can be used to stimulate host cell.

Involvement of the nervous system following experimental infection with Pasteurella multocida B:2 in buffalo (Bubalus bubalis): A clinicopathological study.

Haemorrhagic septicaemia (HS) is an acute, fatal, septicaemic disease of cattle and buffaloes caused by one of two specific serotypes of Pasteurella multocida B:2 and E:2 in Asian and African, respectively. It is well known that HS affect mainly the respiratory and digestive tracts. However, involvement of the nervous system in pathogenesis of HS has been reported in previous studies without details. In this study, nine buffalo calves of 8 months old were distributed into three groups. Animals of Group 1 and 2 were inoculated orally and subcutaneously with 10 ml of 1 × 10(12) cfu/ml of P. multocida B:2, respectively, while animals of Group 3 were inoculated orally with 10 ml of phosphate buffer saline as a control. All calves in Group 1 and Group 3 were euthanised after 504 h (21 day) post-infection, while calves in Group 2 had to euthanise after 12 h post-infection as they develop sever clinical signs of HS. Significant differences were found in Group 2 in the mean scores of clinical signs, gross and histopathological changes which mainly affect different anatomic regions of the nervous system. In addition, successful bacterial isolation of P. multocida B:2 were obtained from different sites of the nervous system. On the other hand, less sever, clinical, gross and histopathological changes were found in Group 1. These results provide for the first time strong evidence of involving of the nervous system in pathogenesis of HS, especially in the peracute stage of the disease.

Clinico-pathology, hematology and biochemistry responses in buffaloes towards Pasteurella multocida type B: 2 immunogen lypopolysaccharide via oral and intravenous routes of infection.

Haemorrhagic septicaemia is a disease caused by Pasteurella multocida serotype B: 2 and E: 2. The organism causes acute, highly fatal septicaemic disease with high morbidity and mortality in cattle and more susceptible in buffaloes. Lipopolysaccharide can be found on the outer cell wall of the organism. Lipopolysaccharide is released during multiplication which leads to inflammatory reaction. It represents the endotoxin of P. multocida type B: 2 and responsible for toxicity in haemorrhagic septicaemia which plays an important role in the pathogenesis of the disease. Therefore, the aim of this study was to investigate the clinical signs, blood parameters, gross post mortem lesions and histopathology changes caused by P. multocida type B:2 immunogen lipopolysaccharide infections initiated through intravenous and oral routes of infection. 9 buffalo heifers were divided equally into 3 treatment groups. Group 1 was inoculated orally with 10 ml of phosphate buffer saline (PBS); Group 2 and 3 were inoculated with 10 ml of lipopolysaccharide broth intravenously and orally respectively. For the clinical signs, there were significant differences (p < 0.05) in temperature between the control, intravenous and oral group. In hematology and biochemistry findings, there were significant differences (p < 0.05) in erythrocytes, haemoglobin, PCV, MCV, lymphocytes, monocytes, eosinophils, GGT and albumin between the control, intravenous and oral group. However, there were no significant differences (p > 0.05) in the MCHC, leukocytes, band neutrophils, basophils, thrombocytes, plasma protein, icterus index, total protein, globulin and A:G ratio between intravenous and oral group. For Group 2 buffaloes, there were gross lesions in the lung, trachea, heart, liver, spleen, and kidney. In contrast, lesions were only observed in the lung, trachea and liver of Group 3 buffaloes. There were significant differences (p < 0.05) in hemorrhage and congestion; necrosis and degeneration; and inflammatory cells infiltration between experimental groups and control group. However, there were no significant differences (p > 0.05) in edema lesion between groups. In conclusion, this study is a proof that oral route infection of P. multocida type B:2 immunogen lipopolysaccharide can be used to stimulate host cell responses where oral vaccine through feed could be developed in the near future.

Clinico-pathology, hematology, and biochemistry responses toward Pasteurella multocida Type B: 2 via oral and subcutaneous route of infections.

BACKGROUND: Pasteurella multocida a Gram-negative bacterium has been identified as the causative agent of many economically important diseases in a wide range of hosts. Hemorrhagic septicemia is a disease caused by P. multocida serotype B:2 and E:2. The organism causes acute, a highly fatal septicemic disease with high morbidity and mortality in cattle and more susceptible in buffaloes. Therefore, the aim of this study was to investigate the clinical signs, blood parameters, post mortem and histopathology changes caused by P. multocida Type B:2 infections initiated through the oral and subcutaneous routes. METHODS: Nine buffalo heifers were divided equally into 3 treatment groups. Group 1 was inoculated orally with 10 ml of phosphate buffer saline; Groups 2 and 3 were inoculated with 10 ml of 10(12) colony forming unit of P. multocida Type B:2 subcutaneously and orally respectively. RESULTS: There was a significant difference (p<0.05) in temperature between the subcutaneous and the control group. The results revealed significant differences (p<0.05) in erythrocytes, hemoglobin, packed cell volume, leukocytes, monocytes, and A: G ratio between the subcutaneous and the control group. Furthermore, there were significant differences (p<0.05) in leukocytes, band neutrophils, segmented neutrophils, lymphocytes, eosinophils, basophils, thrombocytes, plasma protein, icterus index, gamma glutamyl tranferase and A: G ratio between the oral and the control group. The post mortem lesions of the subcutaneous group buffaloes showed generalized hyperemia, congestion and hemorrhage of the immune organs, gastro-intestinal tract organs and vital organs. The oral group buffaloes showed mild lesions in the lung and liver. Histologically, there were significant differences (p<0.05) in hemorrhage and congestion; necrosis and degeneration; inflammatory cells infiltration; and edema in between the groups. CONCLUSION: This study was a proof that oral route infection of P. multocida Type B:2 can be used to stimulate host cell responses where oral vaccine through feed can be developed in the near future.