Enterotoxaemia In Goats Research Articles

Peracute Enterotoxemia in Saanen and Alpine Goat Herd

Background: Enterotoxemia" or "overeating disease" is considered a common and often fatal disease affecting the economy of small ruminant breeding systems. This study presents findings on the occurrence of a peracute form of enterotoxemia in a herd of Saanen and Alpine, including an examination of the clinical signs, post-mortem findings, and methods for diagnosis. examination of the clinical signs, post-mortem findings, and methods for diagnosis. Methods: In a herd of goats a distressing situation occurred where the goats displayed signs (Sudden death and high fever) of peracute enterotoxemia (125 kids). It is noteworthy that these goats had previously been vaccinated against enterotoxemia. The onset of the condition seemed to be linked to three instances of interruption and reconnection of concentrate feed. To obtain a definitive diagnosis, the findings from postmortem examinations and ELISA were utilized. Results: In total, 60 Alpine and 65 Saanen succumbed to this peracute form. These losses occurred over three days but were successfully stopped by re-vaccination after two days. Clinical signs, postmortem observations, bacterial analysis, and ELISA results all provided confirmation of enterotoxemia. Notable findings included high fever (90%), duodenum hyperemia (89%), pulmonary edema (82%), convulsions (43%), and hemorrhage in the pericardium and endocardium (58%). Conclusion: Frequent and consecutive changes in goats' diet or discontinuation of concentrate supply by breeders can disrupt the vaccine-induced immune barrier, increasing the likelihood of enterotoxemia, and leading to casualties and economic losses. Consistent and stable nutrition practices are essential for maintaining vaccination efficacy and preventing enterotoxemia in goats, particularly kids.

Intestinal pathology in goats challenged with Clostridium perfringens type D strain CN1020 wild-type and its genetically modified derivatives.

Clostridium perfringens type D is the causative agent of enterotoxemia in sheep, goats, and cattle. Although in sheep and cattle, the disease is mainly characterized by neurological clinical signs and lesions, goats with type D enterotoxemia frequently have alterations of the alimentary system. Epsilon toxin (ETX) is the main virulence factor of C. perfringens type D, although the role of ETX in intestinal lesions in goats with type D enterotoxemia has not been fully characterized. We evaluated the contribution of ETX to C. perfringens type D enteric pathogenicity using an intraduodenal challenge model in young goats, with the virulent C. perfringens type D wild-type strain CN1020; its isogenic etx null mutant; an etx-complemented strain; and sterile, non-toxic culture medium. The intestinal tract of each animal was evaluated grossly, microscopically, and immunohistochemically for activated caspase-3. Both ETX-producing strains induced extensive enterocolitis characterized by severe mucosal necrosis, apoptosis, and diffuse suppurative infiltrates. No significant gross or microscopic lesions were observed in goats inoculated with the non-ETX-containing inocula. These results confirm that ETX is essential for the production of intestinal lesions in goats with type D disease. Also, our results suggest that the intestinal pathology of type D enterotoxemia in goats is, at least in part, associated with apoptosis.

In silico mutation of aromatic with aliphatic amino acid residues in Clostridium perfringens epsilon toxin (ETX) reduces its binding efficiency to Caprine Myelin and lymphocyte (MAL) protein receptors

Enterotoxaemia (ET) is a severe disease that affects domestic ruminants, including sheep and goats, and is caused by Clostridium perfringens type B and D strains. The disease is characterized by the production of Epsilon toxin (ETX), which has a significant impact on the farming industry due to its high lethality. The binding of ETX to the host cell receptor is crucial, but still poorly understood. Therefore, the structural features of goat Myelin and lymphocytic (MAL) protein were investigated and defined in this study. We induced the mutations in aromatic amino acid residues of ETX and substituted them with aliphatic residues at domains I and II. Subsequently, protein-protein interactions (PPI) were performed between ETX (wild)-MAL and ETX (mutated)-MAL protein predicting the domain sites of ETX structure. Further, molecular dynamics (MD) simulation studies were performed for both complexes to investigate the dynamic behavior of the proteins. The binding efficiency between ‘ETX (wild)-MAL protein’ and ‘ETX (mutated)-MAL protein complex’ interactions were compared and showed that the former had stronger interactions and binding efficiency due to the higher stability of the complex. The MD analysis showed destabilization and higher fluctuations in the PPI of the mutated heterodimeric ETX-MAL complex which is otherwise essential for its functional conformation. Such kind of interactions with mutated functional domains of ligands provided much-needed clarity in understanding the pre-pore complex formation of epsilon toxin with the MAL protein receptor of goats. The findings from this study would provide an impetus for designing a novel vaccine for Enterotoxaemia in goats. Communicated by Ramaswamy H. Sarma

Prevalence of Enterotoxemia (Pulpy Kidney Disease) in Goat: A Comprehensive Review

Goat is considered as poor man’s cow and is among the earliest small ruminant species to be domesticated and are reared for meat and milk purpose, at least since 2500 B.C. in the Middle East. Goats contributes largely to the livelihood of livestock keeping households of low- and medium-input farmers, many of whom have few resources beyond their small holdings and livestock. It has been observed that maximum production can be obtained by protecting them from different prevalent diseases like enterotoxaemia. Enterotoxaemia is a fatal disease of small and large ruminant’s animal species; severe outbreak causes huge economic losses to livestock holders. This disease is also known as pulpy kidney disease due to systemic lesions observed on kidney as it causes nephritis and hydro nephrosis. Enterotoxaemia in goats occurs in four forms, i.e. Per acute, acute, subacute and chronic form. Severe outbreak of this disease observed in warm wet weather at the time of start of monsoon season every year and is having worldwide distribution. Factors which are responsible for exposing the animals towards the enterotoxaemia are sudden changing in diet as animals diet change from poor nutrient pastures to the rich nutrient pastures and changing in environmental temperature as warm wet weather is an ideal environment for the multiplication and toxins production of disease-causing microorganism. It can be diagnosed by detection of specific antibodies, clinical signs and post-mortem lesions. Infected animals can be treated by parental injection of specific chemotherapeutic agents or antitoxins and can be controlled by changing in dietary schedule and vaccination. Still, the pathology and pathogenesis of goat enterotoxaemia is not well understood, with limited studies available in goats. This review provides details information regarding the epidemiology, pathology and pathogenesis of enterotoxaemia in goat which might be helpful for future studies.

Enterocolitis in goats associated with enterotoxaemia in the perspective of two toxins: Epsilon toxin and beta-2 toxin – An immunohistochemical and molecular study

Caprine intestinal diseases associated with clostridia are generally caused by Cpa and Etx encoded alpha (α) and epsilon (ε) toxinotypes of Clostridium perfringens type D respectively. A recent study on goat enterocolitis, demonstrated that the incidence of Clostridium perfringens type-D toxinotype and beta 2 toxins is high, suggesting its role in enterocolitis and many other diseases of goats affecting intestinal tract. Considering this scenario, the present prevalence study was planned to screen the goat intestinal tissues for the presence of the epsilon toxin and beta 2 toxin. Tissue sections from enterotoxaemia suspected cases in 189 goats were collected and epsilon-toxin was demonstrated by immuno-histochemically and toxinotyping multiplex polymerase reaction in 19 animals and beta 2 toxin in 19 animals by multiplex polymerase reaction. Immuno-reactivity to epsilon toxin was detected maximum in distal ileum of goat intestine and this toxin was produced by Clostridium perfringens type D. It suggests that immunohistochemistry is a confirmatory tool for detection of bacterial toxin especially epsilon toxin where isolation and characterisation of bacteria is not possible. Here, we have reported a strong association between ε-toxin (epsilon) and beta-2 toxin in causing disorders of intestine in goats. In addition, we have explored the possible role of cpb2 positive isolates of C. perfringens and their pathogenic effects in causing enterotoxaemia. These determinants help in the understanding of the pathogenesis of enterotoxaemia in goats which needs to be further investigated.

Cattle and goats’ humoral response to vaccination with Clostridium perfringens type D purified epsilon toxoids

Herd vaccination is an important preventive measure against enterotoxemia in ruminants. Vaccination in goats should be performed every four months, and recent studies have shown that immunity in cattle lasts for less than one year. One of the mechanisms for increasing the duration of the immune response is to use purified toxoids as immunogens. The aim of the present study was to evaluate the humoral response in cattle and goats after vaccination with purified and semi-purified Clostridium perfringens type D epsilon toxoid. The following three different vaccines were used: vaccine 1 (V1), a semi-purified toxoid adsorbed to aluminum hydroxide; vaccine 2 (V2), a purified toxoid adsorbed to aluminum hydroxide; and vaccine (V3), a purified toxoid adsorbed on chitosan microparticles. Groups of cattle (n = 6–7) and goats (n = 6–7) were vaccinated on days 0 and 30, and serum samples for antitoxin titration were collected every 30 days for one-year post-vaccination. Goats were revaccinated on day 360, and their serum was evaluated on days 367 and 374. The antibody peaks ranged between 6.90 and 11.47 IU/mL in cattle and from 1.11 to 4.40 IU/mL in goats. In cattle administered with the V1 and V2 vaccines, we observed that the antibody titers were maintained above 0.2 IU/mL until the end of the experiment. In goats, V2 elicited long-lasting antibodies, and all animals maintained the protective titers for 210 days after the first dose. In conclusion, the purified toxoid vaccine with aluminum hydroxide adjuvant was able to induce strong and long-lasting humoral responses in both species and could be an alternative for improving the immunization schedule against enterotoxemia in goats and cattle.

Chemotactic factor inducing Interleukin-8 (IL8) gene is transcriptionally elevated in experimental enterotoxaemia in goats caused by Clostridium perfringens type D

The current study was designed to analyse the effects of experimental induction of enterotoxaemia through intra-duodenal inoculation of C. perfringens type D culture isolated from spontaneous outbreaks in goats. Twenty goats (6–9 month age) were divided into four groups and C. perfringens type D culture was inoculated intra-duodenally as per following: Group-I (whole cultures-WC), group-II (culture supernatant-CS), group-III (washed cells-WS), and group-IV (uninfected control-C). The treated animals were sacrificed after 72 h post infection (hpi), and necropsy showed gross changes including haemorrhages and congestion in the ileal and colon mucosa, pulmonary congestion and edema in lung. Kidney, brain and spleen exhibited severe to moderate congestion. Microscopic changes like haemorrhages, degenerative and necrotic changes in the mucosal epithelium of intestine and haemorrhages in kidney parenchyma were observed in the H&E stained sections. Lung alveolar sacs were filled with proteinaceous fluid. Immunohistochemistry revealed positive immunolabelling for etx (epsilon toxin) in the mucosa of intestine in WC and CS group. Control animals did not exhibit any significant gross or microscopic changes. PCR amplification of DNA extracted from intestinal tissues of WC and CS groups showed positive for etx gene demonstrating the production of epsilon toxin. Transcriptional responses in experimental groups were assessed by quantitative reverse transcription real time PCR (qRT-PCR). Genes including IL-1β and IL2 showed up-regulation in all the experimental groups (WC, CS&WS). Specifically the toxin-based experimental groups (WC&CS) showed up-regulation of the gene responsible for chemotaxis viz. IL-8, while the washed cells group (WS) showed higher transcriptional response to Cathepsin-L (Cat-L) gene denoting the acute inflammatory response due to neutrophil elastase activity. These results take a cue on the evolving nature of the enterotoxaemia in goats due to various strains circulating in the field. The host response and its modulation due to the novel enterotoxaemia strains throws light on the current challenges in efficient control of the disease in goats.

The Challenges of Diagnosis and Control of Enterotoxaemia Caused by <i>Clostridium perfringens</i> in Small Ruminants

Enterotoxaemia is one of the important pathologies caused by Clostridium perfringens, which produces intestinal and systemic disease in goats, sheep and other animals. These Gram-positive anaerobic bacteria are normally resident in the intestinal tract of ruminants but during favourable conditions, proliferate uncontrollably and release toxins which produce disease in the host. Different strains of C. perfringens are responsible for several clinical syndromes, including lamb dysentery, pulpy kidney disease and struck. However, the pathology and pathogenesis of caprine enterotoxaemia is not well understood, with limited studies available in goats. Caprine enterotoxaemia can be controlled with the better understanding of its risk factors and pathogenesis. The diagnosis of enterotoxaemia in animals is complex and often requires group of tests than one single test for better specificity and sensitivity. Tentative diagnosis of enterotoxaemia in sheep and goats is based on the history, clinical signs and gross lesions during post-mortem examination of animals; however, confirmatory diagnosis of enterotoxaemia requires different laboratory diagnostic tools. Toxin detection of C. perfringens in case of enterotoxaemia is furthermost accepted benchmark in establishing a definitive diagnosis of enterotoxaemia in intestinal contents. Measuring urine glucose or observing Gram-stained smears of intestinal mucosa can be used as supplementary tests. However, it is also imperative that enterotoxaemia cannot be ruled out in the event of negativity of aforementioned diagnostic tests. Hence, definitive diagnosis of enterotoxaemia in goats can be achieved with the use of molecular techniques (PCR, ELISA and immune-fluorescence) coupled with toxin detection in intestine or biological assays including mouse inoculation test (MIT). In case of goats, vaccine efficacy is poor which may be due to need of high to moderate level of serum antibodies to protect against both systemic and enteric effects because intestinal form of disease is partially independent of the circulating anti-toxin antibodies. Thus, for the prevention and control of enterotoxaemia in goats and sheep, these aspects must be considered to develop more holistic control measures.

Distribution and antimicrobial resistance patterns of Clostridium Perfringens isolated from vaccinated and unvaccinated goats

This project was designed to find out the effect of enterotoxaemia vaccine in reducing C. perfringens infection in goats and to check antibacterial susceptibility against the highest prevailing genotype. A total of 1344 samples were collected randomly from 1008 unvaccinated and 336 vaccinated goats from various managmental systems in Khyber Pakhtunkhwa, Pakistan. Cultured samples were further identified through colony characteristics, Gram staining, and biochemical analysis. Clostridium perfringens was isolated from79.1% (797/1008) unvaccinated and 65.77% (221/336) vaccinated goats which were further genotyped by multiplex PCR. The genotypic analysis showed that in unvaccinated goats out of positive samples 53.07% were C. perfringens type A, 9.79% were type B and 37.1% were of type D. Similarly in case of vaccinated goats 57.01% were type A, 9.05% were type B and 33.94% were of type D. C. perfringens type C and type E were not detected positive in both vaccinated and unvaccinated goats. Vaccination with enterotoxaemia in goats indicated non-significant effect (P < 0.062) on reduction of C. perfringens isolates. Antibiogram study was performed utilizing a total of 17 antibiotics against the prevailing strains in-vitro. Highest sensitivity was recorded for Ceftriaxone followed by Penicillin G, ciprofloxacin, Ofloxacin, Metranidazol and tetracycline while the strains were found resistant to Streptomycin, Colistin Sulphate, Ampicillin, Amoxicilin and Gentamycin.

Pathology of experimental Clostridium perfringens type D enterotoxaemia in goats

Pathology of experimental <i>Clostridium perfringens</i> type D enterotoxaemia in goats

Clinico-pathological findings of Clostridium perfringens type D enterotoxaemia in goats and its hemolytic activity in different erythrocytes.

The present investigation was conducted to study the effects of experimental Clostridium perfringens type D enterotoxaemia in teddy goats. Clinical signs started to appear after 30 min of experimental infection like anorexia, diarrhea, dehydration, frothing and dyspnea. Gross lesions consisted of severe congestion in tissues of varying intensity with enlarged mesenteric lymph nodes while histological examination revealed edema of lungs, kidney, and lymph nodes and to some extent in brain along with hemorrhages in lungs and intestines. Clostridium perfringens type D carrying alpha and epsilon toxin genes were amplified with amplicon size about 247 bp and 665 bp, respectively. Human erythrocytes showed the highest hemolysis, 68%, followed by mice, 57%, against culture supernatants. The percentage of hemolysis was significantly higher at 37°C as compared to 25°C except for rabbit and dog.

Characterization of the spore-forming Bacillus cereus sensu lato group and Clostridium perfringens bacteria isolated from the Australian dairy farm environment.

BackgroundThe Bacillus cereus sensu lato group and Clostridium perfringens are spore-forming bacteria often associated with food spoilage and which can cause emetic and diarrheal syndromes in humans and ruminants. This study characterised the phenotypes and genotypes of 50 Bacillus cereus s. l. isolates and 26 Clostridium perfringens isolates from dairy farms environments in Victoria, Australia.ResultsFive of the seven B. cereus s. l. species were isolated, and analysis of the population diversity using Pulsed-Field Gel Electrophoresis (PFGE) suggested that the populations are largely distinct to each farm. Enterotoxin production by representative isolates of each B. cereus s. l. species identified was typically found to be reduced in milk, compared with broth. Among the C. perfringens isolates, only two different toxin types were identified, type A and D. Bovine and ovine farms harbored only type A whereas both type A and D were found on two of the three caprine farms.ConclusionsThis study showed that the B. cereus s. l. populations on the sampled farms exhibit a broad diversity in both species and genotypes. The risk of toxin-induced diarrheal illness through consumption of contaminated milk may be limited, in comparison with other food matrices. Type A strains of C. perfringens were the most abundant on dairy farms in Victoria, however type D may be of concern on caprine farms as it can cause enterotoxemia in goats.Electronic supplementary materialThe online version of this article (doi:10.1186/s12866-015-0377-9) contains supplementary material, which is available to authorized users.

Molecular basis of toxicity of Clostridium perfringens epsilon toxin

Clostridium perfringens ε-toxin is produced by toxinotypes B and D strains. The toxin is the aetiological agent of dysentery in newborn lambs but is also associated with enteritis and enterotoxaemia in goats, calves and foals. It is considered to be a potential biowarfare or bioterrorism agent by the US Government Centers for Disease Control and Prevention. The relatively inactive 32.9 kDa prototoxin is converted to active mature toxin by proteolytic cleavage, either by digestive proteases of the host, such as trypsin and chymotrypsin, or by C. perfringens λ-protease. In vivo, the toxin appears to target the brain and kidneys, but relatively few cell lines are susceptible to the toxin, and most work has been carried out using Madin-Darby canine kidney (MDCK) cells. The binding of ε-toxin to MDCK cells and rat synaptosomal membranes is associated with the formation of a stable, high molecular weight complex. The crystal structure of ε-toxin reveals similarity to aerolysin from Aeromonas hydrophila, parasporin-2 from Bacillus thuringiensis and a lectin from Laetiporus sulphureus. Like these toxins, ε-toxin appears to form heptameric pores in target cell membranes. The exquisite specificity of the toxin for specific cell types suggests that it binds to a receptor found only on these cells.

Ulcerative Enterocolitis in Two Goats Associated with Enterotoxin- and beta2 Toxin–Positive Clostridium Perfringens Type D

Enterotoxemia caused by Clostridium perfringens type D in sheep is believed to result from the action of epsilon toxin (ETX). However, the sole role of ETX in the intestinal changes of the acute and chronic forms of enterotoxemia in goats remains controversial, and the synergistic action of other C. perfringens toxins has been suggested previously. The current study examined 2 goats that were found dead without premonitory clinical signs. Gross lesions at necropsy consisted of multifocal fibrinonecrotic enterocolitis, edematous lungs, and excess pleural fluid. Histologically, there were multifocal fibrinonecrotic and ulcerative ileitis and colitis, edema of the colonic serosa, and proteinaceous interstitial edema of the lungs. Clostridium perfringens type D carrying the genes for enterotoxin (CPE) and beta2 toxin (CPB2) was cultured from intestinal content and feces of 1 of 2 goats, while C. perfringens type D CPB2-positive was isolated from the other animal. When multiple colonies of the primary isolations from both animals were tested by Western blot, most of the isolates expressed CPB2, and only a few isolates from the first case expressed CPE. Alpha toxin and ETX were detected in ileal and colonic contents and feces of both animals by antigen capture enzyme-linked immunosorbent assay. CPB2, but not CPE, was identified in the small and large intestines of both goats by immunohistochemistry. These findings indicate that CPB2 may have contributed to the necrotic changes observed in the intestine, possibly assisting ETX transit across the intestinal mucosa.

Genotyping of Clostridium perfringens isolated from domestic and exotic ruminants and swine.

Clostridium perfringens types A, B, C, D and E are known to cause severe enteritis/enterotoxaemia and diseases (especially caused by type A) belonging to the gas oedema complex in many species. Samples from the small intestine as well as faeces of domestic and exotic animals suffering from enterotoxaemic signs or having died within days after first occurance of toxaemia were submitted for typing C. perfringens toxovars by multiplex PCR. The following species have been investigated: domestic sheep (Ovis ammon; n = 10), domestic goat (Capra aegagrus hircus; n = 26), Japanese serow (Capricornis sumatraensis; n = 4), lechwe waterbuck (Hydrotragus leche; n = 1), blackbuck (Antilope cervicapra; n = 1), European reindeer (Rangifer tarandus tarandus; n = 4), domestic swine (Sus scrofa; n = 52), and collared peccary (Tayassu albirostris; n = 1). Interestingly, the predominant C. perfringens toxovar in domestic sheep was type A. This toxovar could also be diagnosed in all reindeer, in three Japanese serows, one lechwe waterbuck and most pigs (n = 47), the majority of those being at suckling age. Type D was the most prevalent toxovar (n = 18) in domestic goats, but also types A and E could be identified as pathogens in this species. Type C could only be found in domestic swine (n = 5) and in one case of clostridiosis in a Japanese serow. Two cases of enterotoxaemia in goats, one case in reindeer, and a single case in blackbuck and collared peccary were caused by C. perfringens type E. Genotyping of C. perfringens is recommended before starting vaccination programmes as it could be shown, that the importance of specific toxovars has been underestimated in specific species and/or age groups.

In vitro effects of Clostridium perfringens type D epsilon toxin on water and ion transport in ovine and caprine intestine

Clostridium perfringens type D produces enterotoxaemia in sheep, goats and other animals. The disease is caused by C. perfringens epsilon toxin, and while enterotoxaemia in goats is usually characterized by enterocolitis, the disease in sheep is characterized by systemic lesions (such as lung and brain oedema) with minor and inconsistent changes observed in the intestine. A possible explanation for these differences is that epsilon toxin is more promptly absorbed by sheep than goat intestine. In an attempt to clarify this, we examined the in vitro effects of epsilon toxin on sheep and goat intestine. Pieces of intestinal mucosa from recently slaughtered animals were mounted in a modified Ussing-type chamber where net water flux ( J w), short-circuit current ( I sc) and tissue conductance ( G t) were simultaneously recorded. After 70 min of incubation with epsilon toxin a reduction in absorptive J w and an increase in I sc and G t were observed in colonic tissues of both sheep and goats, but no alterations were registered in the ileum of either species. These in vitro results show that epsilon toxin affects the transport function of the colonic mucosa but it does not seem to produce any transport alteration in the ileum mucosa.

The early effects of Clostridium perfringens type D epsilon toxin in ligated intestinal loops of goats and sheep.

Clostridium perfringens type D produces enterotoxaemia in goats, sheep and other animals. The disease is caused by C. perfringens epsilon toxin and, while enterotoxaemia in goats is usually characterized by enterocolitis, the disease in sheep is characterized by systemic lesions (such as lung and brain oedema) with minor and inconsistent changes observed in the intestine. A possible explanation for these differences is that epsilon toxin is more promptly absorbed by the ovine than by the caprine intestine. In an attempt to clarify this, we examined the early effects of epsilon toxin on caprine and ovine intestine. Intestinal loop assays were performed to analyse the physiological and morphological changes induced by epsilon toxin in the intestine of these species. Fluid accumulation was observed in caprine and ovine ileum and colon treated with epsilon toxin. Ileal loops from goats treated with epsilon toxin retained sodium and water earlier than ovine ileal loops treated with the same toxin. Histological analysis showed morphological alterations in the colon of both species as early as 2 h after the commencement of epsilon toxin treatment: these changes were more marked in goats than in sheep. No morphological changes were observed in the ileum of either species after 4 h incubation with epsilon toxin. These results suggest that epsilon toxin modifies ion and water transport in the small and the large intestine of goats and sheep through different mechanisms.

Enterotoxaemia in goats in Australia.

Enterotoxaemia in goats in Australia.

Protection of goats against experimental enterotoxaemia by vaccination with Clostridium perfringens type D epsilon toxoid.

Enterotoxaemia in goats is mainly characterized by enterocolitis, and it has been suggested that the poor efficacy of commercial vaccines in preventing the disease is due to the local action of Clostridium perfringens toxin/s within the intestine, where circulating antibodies might not exert their action. Five goat kids were vaccinated with an incomplete Freund's adjuvant C perfringens type D epsilon toxoid vaccine on three occasions at three-week intervals, four similar kids were vaccinated with a commercial enterotoxaemia vaccine at the same times, and five other unvaccinated kids were used as controls. All the animals were challenged intraduodenally, one week after the last vaccination, with C perfringens type D filtered culture supernatant. At the time of challenge, the level of epsilon toxin antibodies in the serum of the Freund's adjuvant-vaccinated kids ranged between 2.45 and 230 iu/ml, while the kids that received the commercial vaccine had levels between 0.22 and 1.52 iu/ml. No clinical or postmortem changes were observed in the kids that received the Freund's adjuvant-vaccine. Three of the four kids that received the commercial vaccine developed mild, pasty diarrhoea, with a slight reddening of the colonic mucosa being observed postmortem. All the unvaccinated kids developed severe diarrhoea, respiratory distress and central nervous system signs, and were killed humanely between six and 24 hours after challenge. The postmortem changes consisted of pseudomembranous colitis, lung oedema and perivascular oedema of the brain. Moderate to high serum levels of anti-epsilon antibody appeared to protect the goats against both the systemic and the intestinal effects of C perfringens type D toxins.

Experimental Clostridium perfringens type D enterotoxemia in goats.

The effects of intraduodenal administration of Clostridium perfringens cultures and culture products in goats were evaluated to develop a reliable experimental model of enterotoxemia in this species. Five conventionally reared, 11-16-week-old Angora goat kids were dosed intraduodenally with whole cultures of C. perfringens type D; five similar animals were dosed with C. perfringens type D filtered culture supernatant; and a third group of five kids was dosed with C. perfringens type D washed cells. Two kids were used as controls and received sterile, nontoxic culture medium intraduodenally. All animals received starch solution into the abomasum. All five kids inoculated with whole culture and three of five dosed with culture supernatant and with washed cells developed central nervous system signs. Diarrhea was observed in two of five kids inoculated with whole culture, in all five of those dosed with culture supernatant, and in three of five of those that received washed cells. The most striking postmortem findings consisted of lung edema, necrotizing pseudomembranous colitis, and cerebral vasogenic edema. The protocol thus provided a reasonable model of naturally occurring enterotoxemia in goats, producing a range of clinical signs and postmortem changes similar to those observed in the natural disease.