A double-antibody sandwich ELISA for detection of antibodies directed against the exotoxin of Corynebacterium pseudotuberculosis, the cause of caseous lymphadenitis (CL) in small ruminants, was developed. A concentrated exotoxin was used. For interpretation of ELISA results, these sera were tested: sequentially obtained sera of C pseudotuberculosis-inoculated goats and sheep that were monitored for 68 weeks; sequentially obtained sera from 80 goats of 3 flocks with CL; sera from 652 goats of 7 flocks without CL; sera from 160 sheep of 4 flocks without CL; and 2,265 caprine and 208 ovine sera submitted for diagnostic testing. Data regarding the infection status and history of 10,454 of the 23,302 animals were collected after testing; most of these were goats that had been part of a CL control program. Specificity and sensitivity of the ELISA were nearly 100%. Subsequently, 31,978 animals from which no data on infection status of flocks had been collected were then tested. It was concluded that the ELISA is a useful diagnostic test for CL eradication programs. Sera with doubtful or inconclusive ELISA results were examined by use of immunoblot analysis. Proteins from C pseudotuberculosis culture supernatant were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and blotted onto nitrocellulose. Six proteins with molecular mass of 68, 65, 39, 38, 31, and 29 kDa reacted with sera from goats and sheep with experimentally induced or naturally acquired infection. Immunoblot analysis was valuable in classifying sera with doubtful or inconclusive results by ELISA.

A double-blind randomized clinical trial was undertaken to determine the value of parenterally administered Streptococcus equi M-protein vaccine in foals during an epizootic of strangles. Weaned mixed-breed foals (n = 664) housed on 2 adjacent feed-lots (A and B) arrived over a 5-day period, 2 weeks before primary vaccination. Foals in lot B (n = 114) were randomly administered vaccine (n = 59) or saline solution (placebo; n = 55) on 3 occasions at biweekly intervals. Foals in lot A (n = 450) were given 1 dose of vaccine (n = 225) or placebo. The following clinical observations were scored blindly by a single observer for all foals in lot B and for 120 (randomly sampled) foals in lot A on a single day, 2 (lot B) and 6 (lot A) weeks after final vaccination: cervical lymphadenopathy, type of bilateral nasal discharge, and palpable swelling at injection site(s). Bacteriologic culture of nasal swab specimens or lymph node aspirates from selected foals with clinical disease yielded S equi. Cervical lymphadenopathy was observed in 17 of 59 (29%) vaccinates and 39 of 55 (71%) nonvaccinated controls in lot B and in 32 of 60 (53%) vaccinates and 29 of 60 (48%) controls in lot A. Contingency X2 analysis confirmed significantly lower cervical lymphadenopathy rate (X2 = 18.5; P < 0.001) and prevalence of mucopurulent nasal discharge (X2 = 11.4; P < 0.01) for vaccinates in lot B only. Swelling(s) at the vaccine injection site were palpated in 44% of lot B and 29% of lot A vaccinates vs < 2% of placebo controls. In the face of intense natural exposure, foals inoculated 3 times with M-protein vaccine were less than half as likely to have clinical signs of strangles as were nonvaccinated horses.

Consumption of chlortetracycline (CTC) at concentration of 220 mg/kg of feed for 4 weeks in experiment 1 and at concentrations of 110 and 220 mg/kg for 3 weeks and 440 mg/kg for 2 weeks in experiment 2 failed to eliminate streptococci-induced lymphadenitis from swine referred to as principals. Abscesses, mostly in the head and neck, developed in at least a third of all swine in the various groups fed these CTC concentrations. Feeding of 220 mg of CTC/kg of feed in experiment 1 began 12 weeks after exposure of principals to an untypeable group E streptococci (GES; isolate 3X29A). In experiment 2, feeding of 110 and 220 mg of CTC/kg of feed began 5 weeks after exposure of principals to GES and feeding of 440 mg of CTC/kg of feed began 6 weeks after exposure. One or more cohabitating sentinel swine of experiment 1 and one or more sentinels in all groups of principals of experiment 2, except group 2, developed abscesses that were mostly in the head and neck. In experiment 2, correlation between serum GES antibody titer and development of one or more abscesses in the principals was highly significant (P < 0.01); however, correlation between antibody titer and abscesses in the sentinels only approached significance (P < 0.10).

Caseous lymphadenitis (CIA) caused by Corynebacterium pseudotuberculosis is a worldwide disease of sheep and goats and is characterized by development of pyogranulomas in lymph nodes and lungs. Control of this disease by vaccination remains controversial, although toxoid vaccines are now commercially available in some countries. To determine the efficacy of acquired immunity to control CLA, the effect of primary infection on subsequent challenge exposure was investigated. Adult seronegative ewes were primarily inoculated with a streptomycin-sensitive strain of C pseudotuberculosis on the external part of the left ear and thereafter challenge-exposed by inoculation of the streptomycin-resistant strain 19R in the right ear. This protocol indicated that primary infection with at least 10(7) viable bacteria induced strong protection against subsequent challenge exposure; the ewes with primary infection did not develop lesions as a result of challenge exposure, whereas immune-naive ewes developed numerous pyogranulomas in the right car, in lymph nodes draining the inoculation site, and in the lungs. However, ewes with primary infection remained carriers of the disease as a result of primary inoculation. These results offer experimental support for development of more effective vaccination to control CLA, in sheep and goats, and this model indicates that animals with primary infection can be used as positive controls for protection when testing a candidate vaccine against CLA.

Chromobacterium violaceum is a facultative anaerobic, gram-negative rodshaped bacteria normally found in soil and stagnant water of tropical and subtropical countries. Infections of Chromobacterium violaceum are rare among mammals, but the first human infection were reported in Malaysia in 1927. This clinical case reports two separate cases of Chromobacterium violaceum infection in two sub-adult male Black-handed Gibbon (Hylobates agilis). Both animals were presented with the history of diarrhea, pyrexia and inappetance. From the physical examination, the findings were high body temperature, dull, inactive, soft fecal stained at the rectum and small open wound at lower limb of one of the case. The treatment given was antipyretic and multivitamin. Unfortunately, due to poor prognosis both patients died within 48 hours after presentation and treatment. Autopsy examinations wereperformed to find out the cause of death. Post mortem examination findings revealed hepatomegaly with multiple size whitish-yellow spots on the liver surface, congestion and enlargement of spleen and lymph node, congestion of lung and loss of demarcation between renal cortex and medulla of the kidney. The cellular changes via histopathological findings of kidney, spleen, lung and liver were suggestive of septicaemia. The gross and histopathologicalfindings were supported by the isolation of Chromobacterium violaceum via bacterial isolation and identification from lung, liver, spleen and kidney. Thus, the cause of death of the two sub-adult male Black-handed gibbon in this case are due to septicaemiadue to Chromobacterium violaceum infection.

Caseous lymphadenitis (CLA) is a chronic and contagious disease of sheep and goats caused by Corynebacterium (C.) pseudotuberculosis. A four-year-old female Saanen dairy goat was submitted to the Animal Disease Diagnostic Center at National Veterinary Research and Quarantine Service. The clinical signs of the goat were emaciation, abortion and quadriplegia. The multifocal nodules of lymph nodes were encapsulated and filled with whitish caseous contents on the cut surface. Histopathologically, lymph nodes displayed suppurative and necrotizing granulomas. Caseous necrosis was diffusely observed in the center of the lymph nodes. Gram positive bacilli were shown in the lesions. C. pseudotuberculosis was isolated and confirmed by the biochemical tests and PCR assay. Based on clinical signs, histopathological examination and bacterial isolation, we diagnosed this case as CLA. To our knowledge, this is the first report of CLA in a Saanen dairy goat in Korea.

Conventional methods of detecting Corynebacterium pseudotuberculosis, a bacterium that causes caseous lymphadenitis (CLA) in sheeps and goats focused on several serodiagnostic tests such as ELISA, Western blotting and various inhibition and precipitation techniques. This paper described a Surface Plasmon Resonance (SPR) protocol for the direct detection of polyclonal&#xD;antibodies against Corynebacterium pseudotuberculosis with immobilisation of the antigen on unmodified transducer surface. The lower limit of detection was determined to be 2 μg mL-1 of immobilised antigen (Ag). Sufficient binding interaction was monitored on unmodified transducer; and saturation of the binding interaction was observed at 80 μg mL-1 of interacted antibody.