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Mycoplasma bovis and Mycoplasma mycoides subspecies mycoides small colony (MmmSC) are causes of bovine mycoplasmosis and contagious bovine pleuropneumonia (CBPP), respectively, and are responsible for serious economic losses in cattle around the world. CBPP was last reported in Poland in 1939 but bovine mycoplasmosis is believed to be endemic. A survey of 3670 serum samples for antibodies to M bovis and MmmSC from 361 herds in 16 Polish provinces Poland between 2007 and 2010 found no evidence of CBPP. The seroprevalence of M bovis, however, appeared high with 76.7 per cent of samples giving a positive reaction in the ELISA test, which did not appear to reflect the clinical disease status of the cattle. Adjusting the sensitivity of the test reduced the prevalence to 28.2 per cent and reflects the levels reported in other European countries.

An indirect ELISA, using local strains of Mycoplasma agalactiae and Mycoplasma mycoides subspecies mycoides large colony (MmmLC), was applied to evaluate the seroprevalence of M agalactiae and MmmLC in flocks of goats on each of the Canary Islands. In total 3890 samples of serum were collected from 204 flocks. The results indicated that the seroprevalence of both organisms is high on all the islands; average values of 55 per cent and 67 per cent were recorded, respectively, for M agalactiae and MmmLC.

Goats on two zero grazed farms carrying 1621 animals with a history of contagious caprine pleuropneumonia were subjected to a vaccine trial with an inactivated mycoplasma F38 vaccine. The results indicated that the vaccine produced an immune response, that it was very effective in reducing morbidity and mortality rates, and that a booster dose one month after the first dose of vaccine gave extra protection.

The results of an enzyme-linked immunosorbent assay (ELISA) For the detection of antibody against Mycoplasma mycoides subsp mycoides are presented. Antibody was detected in the sera of cattle at least 19 months after recovery from an infection and at least 23 months after vaccination. Almost half the sera of some animals in an area of Nigera where contagious bovine pleuropneumonia is enzootic contained antibody. Antibody was rarely detected when the same sera were examined by other established serological tests, emphasising the sensitivity of the ELISA.

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.

In the light of the recent outbreaks of rinderpest in Africa a further assessment of the efficacy of the simultaneous inoculation of rinderpest virus vaccine and contagious bovine pleuropneumonia vaccine was undertaken. Groups of cattle were inoculated with a dual preparation of rinderpest vaccine virus and Mycoplasma mycoides subspecies mycoides or M mycoides alone. These groups were then challenged with M mycoides, first unsuccessfully by an in-contact challenge method and then by subcutaneous challenge. All animals were examined clinically after challenge for evidence of contagious bovine pleuropneumonia and serologically for rinderpest virus and M mycoides mycoides antibodies. There was no evidence that the serological response to the dual vaccine was in any way less than that to either agent given alone and no clinical disease was detected in these animals after in-contact challenge. However, after subcutaneous challenge, the dual vaccinated groups reacted similarly to an unvaccinated control group and unlike the group vaccinated only with M mycoides. This would indicate that the rinderpest virus component of the dual vaccine interfered with the ability of the M mycoides component to induce a fully effective immune response. In the pan African rinderpest campaign the use of the dual vaccine in areas where contagious bovine pleuropneumonia occurs should be carefully considered; in areas where the disease does not occur it is contraindicated.