Clinio-Pathological Changes in Goats Challenged with <i>Corynebacterium Peudotuberculosis</i> and its Exotoxin (PLD)

Abstract

Caseous lymphadenitis (CLA) is a chronic disease caused by Corynebacterium pseudotuberculosis. However, there is a paucity of data about the C. pseudotuberculosis exotoxin, phospholipase D (PLD) response during the course of CLA. Therefore, this study was conducted to observe the clinical signs and the cellular changes after an experimental infection of the C. pseudotuberculosis and phospholipase D challenge. Twenty six crossbred Boer goats aged 12-14 months were divided into 3 groups; the first group n=6 was inoculated with 1ml sterile PBS s.c. as the control. The second group n=10 was inoculated with live C. pseudotuberculosis 1×10 9 cfu s.c. The third group n=10 was i.v. inoculated with PLD 1mL/20 kg, BW. Both the C. pseudotuberculosis and the PLD treated groups showed a significant increase (p<0.05) in body temperature, heart rate, respiratory rate and body score. Pathologically, the C. pseudotuberculosis and the PLD treated groups showed a significant cellular changes (p<0.05) manifested as edema, congestion, infiltration of inflammatory cells mainly lymphocytes and macrophages, hemorrhage, degeneration and necrosis in the visceral organs including the lungs, heart, liver, spleen, kidneys and lymph nodes. C. pseudotuberculosis infected group showed abscessation of the lymph nodes and some of the visceral organs. In contrast, PLD inoculation did not lead to any abscess formation in the lymph nodes neither in the visceral organs. It concluded that the C. pseudotuberculosis caused typical CLA disease with short incubation period of two weeks. The PLD inoculation showed little clinical signs and it did not lead to abscesses formation externally neither internally, however, it caused obvious cellular changes in the visceral organs as well as in the lymph nodes. PLD play a key role in CLA development, yet it is impossible to trigger granulomatous lesion without the C. pseudotuberculosis being present.

Suppurative Pneumonia and Lymphadenitis in a Goat Associated with Infection by Corynebacterium Pseudotuberculosis A Case Study

“…This finding agreement to previously reports (Fontaine and Baird, 2008;Radostits et al, 2007). Mahmood et al (2015) described lung lesion in experimentally induced infection by C. pseudotuberculosis in goat, which showed similar finding to present study.…”

Reproductive Pathological Changes Associated with Experimental SubchronicCorynebacterium pseudotuberculosisInfection in Nonpregnant Boer Does

“…These findings are supported by Adza Rina et al [ 6 ], who found that goats inoculated with 10 7 concentrations of live C. pseudotuberculosis through intranasal route developed abscesses in the mesenteric and supramammary lymph nodes compared to oral and intradermal routes. Similarly, Mahmood et al [ 27 ] observed severe abscess formation, congestion, hemorrhage, degeneration and necrosis, and inflammatory cellular infiltration in Boer goats subcutaneously inoculated with C. pseudotuberculosis as compared to those inoculated intravenously with its phospholipase D. However, all of these studies failed to investigate the association of the iliac lymph nodes and pathological changes in the female reproductive organs such as the uterus and ovaries.…”

Linfadenitis caseosa: factores de virulencia, patogénesis y vacunas. Revisión

“…La infección primaria ocurre en el sitio de ingreso de la bacteria, con diseminación hematógena y linfática formando abscesos en los nódulos linfáticos más cercanos al sitio de infección (parotídeos, submandibulares, prefemorales, preescapulares, poplíteos o mamarios). Luego ocurre una infección secundaria con la formación de abscesos en ganglios linfáticos (torácicos, bronquiales y mediastínicos) y diversos órganos (63,64) . En ovinos la apariencia morfológica de los nódulos abscedados es la característica de capa de cebolla al presentar una distribución en láminas concéntricas fibrosas separadas por material caseoso.…”

“…Las bacterias viables se diseminan a través de los vasos linfáticos y penetran otros linfonodos y vasos sanguíneos, llegando a diferentes órganos donde se repite la formación de abscesos. Este comportamiento origina las manifestaciones clínicas de la enfermedad de tipo visceral, que afecta nódulos linfáticos internos y órganos especialmente pulmones e hígado (61,64) .…”