A passive haemagglutination test for detection of antibodies against Mycoplasma mycoides subsp. mycoides using glutaraldehyde-fixed sheep erythrocytes.

A simple passive haemagglutination test using the microtitre technique was developed for the detection of antibodies against Mycoplasma mycoides subsp. mycoides infection in cattle. Of the four different concentrations (0.1, 0.2, 0.25 and 0.5%) of glutaraldehyde used for the fixation of sheep erythrocytes, antigens prepared with erythrocytes fixed with 0.2 and 0.25% concentrations of glutaraldehyde gave the best results. The test was found to be very practical, sensitive specific and reproducible. It also compares favourably with the complement fixation test.

Characterisation of mycoplasmas isolated from genital tract infections of sheep in Nigeria.

Four mycoplasma-like organisms isolated from ewes with mucopurulent vaginal discharge and swollen vulva were characterised. Biochemical tests showed three of the isolates to be negative for glucose fermentation and arginine hydrolysis, while the remaining isolate was negative for glucose fermentation but hydrolysed arginine. Serological identification using the growth inhibition, growth precipitation and indirect immunofluorescence tests indicated the three similar isolates as Mycoplasma bovigenitalium and the other isolate as Mycoplasma arginini. There are apparently no previous reports of the isolation of these organisms from the genital tract of sheep in Nigeria.

An epizootic infection of Citrobacter freundii in a guineapig colony: short communication.

An epizootic infection of Citrobacter freundii in a guineapig colony is reported. From 1300 guineapigs maintained in a colony, a total of 115 guineapigs died. Lesions found postmortem were suggestive of acute pneumonia and enteritis. Citrobacter freundii was consistently isolated from necropsy specimens of lung, liver, spleen and intestines of the animals. The source of infection was not ascertained.

Concurrent infection of a Patas monkey (Erythrocebus patas) by Citrobacter freundii and Trichuris trichiura.

Concurrent infection of Citrobacter freundii and Trichuris trichiura in a Patas monkey (Erythrocebus patas) is reported. A synergistic effect of both organisms contributing to host mortality in this case is suggested.

The T1 vaccine used in the control of contagious bovine pleuropneumonia in Nigeria.

A lyophilised T1 vaccine was produced by direct lyophilisation of a 72-hour broth culture to which 10% sterile sucrose solution was added. Each vial contained 2 ml to make a total of 10 doses when reconstituted. Each ml of the product contained an average of 109 colony forming units of the organism. When injected at the tip of the tail or subcutaneously behind the shoulder of 2,000 zebu and 1,0000 Ndama cattle, no outward reactions were observed. 12 zebu cattle were vaccinated and challenged 6 months later by direct contact with artificially infected cattle for 4 months. All the animals were completely protected against the disease.

Immunodepressive effects of trypanosomal infection in cattle immunized against contagious bovine pleuropneumonia.

Groups of cattle infected singly with Trypanosoma vivax and T. congolense and, with a combination of T. vivax and T. congolense, were vaccinated against contagious bovine pleuropneumonia (CBPP) 6 weeks before or after infection. All animals were revaccinated 12 weeks after primary vaccination. The primary antibody responses in cattle vaccinated 6 weeks after infection with T. vivax and a combination of T. vivax plus T. congolense were slightly depressed in contrast to other groups which were similar in their response to the control group. Although secondary antibody responses developed in all infected groups, with a delay in those infected with T. congolense, they did not reach the levels of the controls. In spite of the slight depression in antibody responses, however, 50% of the vaccinated trypanosomal animals contracted CBPP on exposure to experimental infection while the vaccinated controls were immune. It is suggested that the protective immunity to CBPP engendered by vaccination is impaired during infection with African trypanosomes and that the level of antibody response to CBPP vaccination in trypanosomal animals does not reflect the degree of immunodepression. The importance of trypanosomiasis control in ensuring success of vaccination campaigns against CBPP is discussed.

Clostridium perfringens type A enterotoxaemia in pigs: a report of five cases.

Enterotoxaemia caused by Clostridium perfringens type A in five intensively managed pigs is reported. The condition was precipitated by constipative digestive disturbance. Diarrhoea was not observed in the five animals before death.

Synovial immunoglobulin and antibody in vaccinated and nonvaccinated calves challenged with Mycoplasma bovis.

Intravenous injection of Mycoplasma bovis produced in calves arthritis with synovial infiltration of lymphocytes, macrophages and neutrophils. Necrosis was observed focally around blood vessels. Joint spaces contained fibrinopurulent exudate. Parenterally vaccinated calves had a markedly reduced frequency of arthritic joints. Immunoglobulin classes and specific antibody in joint fluids were quantitatively less than in sera but significantly greater in arthritic than in normal joints. The possible mechanisms of induction of joint fluid antibody are discussed.