A primary Corynebacterium pseudotuberculosis low dose infection in alpacas (Lama pacos) protects against a lethal challenge exposure

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Abstract

Corynebacterium pseudotuberculosis is the agent of alpaca's lymphadenitis. The present study was to demonstrate the effect of a primary infection with low (1.1 × 103), moderate (1 × 104), and high (1.2 × 105) doses of C. pseudotuberculosis against a significant higher challenge dose of 9 × 108 CFU of C. pseudotuberculosis. Three groups of 4 healthy male alpacas were inoculated subcutaneously (SC) in the left flank behind the costal arch with the above doses of bacteria. A fourth group of 4 alpacas was sham inoculated with phosphate buffered saline as control. After 5 weeks all animals were challenged with a dose of 9 × 108 CFU of C. pseudotuberculosis inoculated SC in the right flank. The alpacas were clinically inspected for local and regional abscesses, body temperature and behavior changes. The primary infected alpacas had a febrile response, and abscesses at the inoculation point and regional lymph nodes. However, after challenge, the primary infected animals showed no superficial lesions or febrile response. In contrast, the immune naïve alpacas from group D developed a severe disease characterized by fever, abscesses in regional lymphnodes, and in one alpaca a subcutaneous edema and sudden death 2 weeks after exposure. In addition, primary infected alpacas had a robust antibody response against C. pseudotuberculosis cell wall antigen with significant differences with respect the naïve challenged alpacas. At necropsy, the primary infected alpacas had abscesses only in the regional or internal renal-lymph nodes from the left or primary inoculation side of the body, with no lesions in the right challenged side. In contrast, the primary sham inoculated alpacas had abscesses in the regional and internal lymph nodes from the right challenged side. This work showed that a primary infection with at least 1.1 × 103 viable C. pseudotuberculosis induces protection against a second high dose exposure to this bacterium. These results will be useful for further study of prevention methods to control lymphadenitis in alpacas.

Introduction

Corynebacterium pseudotuberculosis is associated with a severe granulomatous lymphadenitis in South American camelids. This chronic infectious disease is characterized as a progressive enlargement of the sub-lumbar or renal lymph nodes (Braga, 1993). In alpacas under natural conditions of extensive management in the Andes, there is no opportunity to treat each abscess case, especially if it is localized internally. In intensive production of alpacas in USA, most of the abscesses in young alpacas are localized in the head, cervical or thoracic area (Anderson et al., 2004). This localization of abscesses was described also for young alpacas under extensive management in the Andes (Villena, 1985).In sheep and goats the disease produced by C. pseudotuberculosis is known as caseous lymphadenitis (CLA), and is characterized by pyogranulomas in superficial and visceral lymph nodes, and organs, especially the lungs (Batey, 1986). Susceptibility to CLA has been demonstrated by experimental infection in sheep; by the inoculation of the external ear (Pépin et al., 1988), intralymphatic (Burrell, 1978), or intradermal inoculation (Brogden, 1984). In goats, the inoculation by the intradermal and intravenous route resulted in mediastinal and lung abscesses (Brown et al., 1985). Control of this disease in lambs and goats was achieved with vaccines containing different antigen or viable bacteria compositions. The filtrate vaccine immunization resulted in antibody responses to numerous cellular antigens in lambs (Ellis et al., 1991). Inactivated whole-cell antigen and detoxified exotoxin of C. pseudotuberculosis has been developed and evaluated for vaccine potential, and reduced the prevalence of internal abscesses (Tachedjian et al., 1995, Hodgson et al., 1999). The potency of a toxoid vaccine for the use in alpacas was assayed in mice with 80% of protection after a challenge IV lethal dose of C. pseudotuberculosis from alpaca origin (Braga et al., unpublished data). In goats, small doses of live C. pseudotuberculosis prevented the development of abscesses in the draining area or in internal organs (Johnson et al., 1993). The purpose of this study was to evaluate whether or not a primary C. pseudotuberculosis low infection in alpacas would be protective against a 10× challenge exposure, and if this protection is dose-dependant. This study will serve to elucidate this disease in alpacas in order to further develop a preventive method of control.

Section snippets

Animals

Sixteen, 2 year-old male alpacas destined for slaughter, originating from healthy flocks in which CLA had never been observed were used. The animals were raised together for 6 weeks before the experimental infection,. The alpacas were then weighed and housed at random in 4 pens of 6 m × 20 m, with four individuals each. They were provided with hay/ryegrass and water ad libitum. To sacrifice the alpacas by exanguination, they were anesthetized first with a combination of Xylazine–Ketamine at 0.5 

Clinical responses to C. pseudotuberculosis primary infection

All alpacas infected with 1.1 × 103, 1 × 104 or 1.2 × 105 viable C. pseudotuberculosis CFU, groups A, B and C, respectively, showed a febrile response (Fig. 1) with significant differences with respect to sham inoculated group D. In addition to changes in body temperature, swelling and abscess formation was observed at the inoculation site with positive isolation of C. pseudotuberculosis from pus that flowed through fistulae. After 2 weeks PI, the initial lesion progressed to scars of approximately

Discussion

Primary infections with low (1 × 103), moderate (1 × 104) or high (1 × 106) of live C. pseudotuberculosis CFU were protective against a challenge dose of 9 × 108 live C. pseudotuberculosis CFU, which produced a severe lymphadenitis in immune naïve alpacas.

Under natural conditions in the Andes, most of the abscesses in adult alpacas and llamas were observed externally in the mammary gland or were related with draining lymph nodes, and internally in the sub-lumbar area or renal lymph node (Braga, 1993).

Acknowledgments

Especial thanks to Dr. James Higgins for statistical consultation and to Mrs. Jacque Staat and Mrs. Megan Haugh for the manuscript review. This work was supported by the International Foundation of Science IFS Stockholm Sweden, Grant B:2083-2 and the Consejo Nacional de Ciencia y Tecnologia CONCYTEC, Lima, Peru.

References (22)

  • Braga, W. 1994. Corynebacterium pseudotuberculosis infection in alpacas: Pathogenesis and immunity. Thesis MS...

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      This is in harmony with the report in earlier studies that reported that C. pseudotuberculosis infected small ruminants experience a transient temperature increase in the first few days [19]. Similar findings found that severe reaction was observed in the naïve subjects two weeks post inoculation with a high dose (9 × 108 cfu) of C. pseudotuberculosis and it was represented by fever and eventually resulted in the death of the animal [20]. Other related studies have also reported increases in temperature following challenge with C. pseudotuberculosis in small ruminants [21,22].

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      The significance of the disease is evidenced by the scientific research and political debate which has been ongoing in relation to this topic for over a century. Other animal species in which infection with C. pseudotuberculosis is relatively common, include horses (Addo et al., 1974; Miers and Ley, 1980; Poonacha and Donahue, 1995), cattle (Purchase, 1944; Adekeye et al., 1980; Kariuki and Poulton, 1982; Anderson et al., 1990; Shpigel et al., 1993; Yeruham et al., 1997), llamas and alpacas (Braga et al., 2006, 2007) and buffalo (Ali and Zaitoun, 1999). In addition, while not as common, C. pseudotuberculosis infection of humans has been reported on several occasions (Lopez et al., 1966; Hamilton et al., 1968; Hill et al., 1978; Henderson, 1979; Keslin et al., 1979; Goldberger et al., 1981; House et al., 1986; Mills et al., 1997; Peel et al., 1997; Join-Lambert et al., 2006), making the disease a potential zoonosis.

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