Proposal for designation of F38-type caprine mycoplasmas as Mycoplasma capricolum subsp. capripneumoniae subsp. nov. and consequent obligatory relegation of strains currently classified as M. capricolum (Tully, Barile, Edward, Theodore, and Ernø 1974) to an additional new subspecies, M. capricolum subsp. capricolum subsp. nov.

A subspecies relationship with the existing species Mycoplasma capricolum is appropriate for the F38 group of mycoplasmas, the causative agent of classical contagious caprine pleuropneumonia. We believe that this classification is justified on the basis of the close DNA-DNA relationship recently reported for isolates belonging to the two groups and the other known serological and biological similarities and differences of these organisms. Strain F38T (T = type strain) and taxonomically indistinguishable strains are therefore proposed as members of a new subspecies of M. capricolum, M. capricolum subsp. capripneumoniae. Strain F38 (= NCTC 10192) is the type strain of M. capricolum subsp. capripneumoniae subsp. nov. As a consequence of this subdivision of the species M. capricolum, strains previously classified as M. capricolum are now necessarily relegated to subspecies status, as M. capricolum subsp. capricolum subsp. nov. Strain California kid (= ATCC 27343 = NCTC 10154) is the type strain of M. capricolum, as well as of M. capricolum subsp. capricolum. A taxonomic description of M. capricolum subsp. capripneumoniae and a brief amended description of M. capricolum subsp. capricolum are presented.

The occurrence of infectious diseases in mixed farming of domesticated wild herbivores and livestock in Kenya. II. Bacterial diseases.

The prevalence of antibodies to Brucella spp., Mycobacterium paratuberculosis and the Mycoplasma spp. causing contagious bovine pleuropneumonia and contagious caprine pleuropneumonia was determined in various species of ruminants on a ranch in the semi-arid zone of southeastern Kenya. Antibody titers to Brucella spp. were found in eland (Taurotragus oryx), oryx (Oryx beisa) and camels (Camelus dromedarius). Reactors were not found in buffalo (Syncerus caffer), sheep (Ovis aries) and goats (Capra hircus). Brucella sp. was not isolated from eland and camels. Antibody titers to M. paratuberculosis were found only in camels and goats. Mycobacteria were not detected in feces of two serologically positive camels. Significant serum antibody titers to Mycoplasma mycoides mycoides were found only in camels. Antibody titers to Mycoplasma sp. (strain F38), which causes contagious caprine pleuropneumonia, were found in buffalo, cattle and camels but not in the other species. Attempts to isolate the Mycoplasma sp. from nasal secretion of the buffalo and camels failed. The possible occurrence of tuberculosis in camels is discussed. Under the conditions at the ranch, contagious bacterial diseases appear to be of minor importance in the domesticated wild herbivores. The introduced camels, however, might be a source of various infections such as brucellosis, mycoplasmosis and possibly tuberculosis for the other susceptible species.

Experimental infection of castrated lambs with Mycoplasma agalactiae.

The course of experimental infection in groups of 6-month-old castrated lambs with field isolates of Mycoplasma agalactiae from France was followed culturally and serologically for 7 months. Infection with an ovine field isolate following inoculation by different routes and contact exposure was compared with that caused similarly by a caprine field isolate. The prolonged infections produced were symptomless apart from limited arthritis in one animal inoculated with the isolate from sheep and increased lachrymation in another associated with the goat isolate. The ovine isolate was more virulent in that ante- and post-mortem recoveries of the organism were more consistent and the serological responses more pronounced. Serological responses varied between animals and between strain infections, and the results of the film inhibition test were more consistent than those of the complement fixation test. The limitations of both these tests for detecting carrier infections are discussed.

Role of mycoplasma strain F38 in contagious caprine pleuropneumonia.

The role of the F38 group of mycoplasma in contagious caprine pleuropneumonia is assessed with reference to certain criteria whereby a causative relationship between a particular agent and the disease in question is established. The evidence that Mycoplasma mycoides subsp. mycoides (large colony) or M. mycoides subsp. capri may be involved in the disease is similarly considered.

Mycoplasma mycoides infections in ruminants: the current situation.

Recent reports of naturally occurring infections with the large colony variant of Mycoplasma mycoides subsp. mycoides are collated and considered together with the results of experimental pathogenicity studies. The information is assessed to indicate where further investigation would add to knowledge of M. mycoides subsp. mycoides as a ruminant pathogen.

Egg transmission of a respiratory isolate of Mycoplasma synoviae and infection of the chicken embryo.

Egg transmission of Mycoplasma synoviae (Ms) was demonstrated in broiler breeder birds of over 40 weeks of age from a commercial flock that had been infected during rearing and in birds experimentally inoculated before onset of lay. Infection of growing birds with Ms did not prevent egg transmission in adult life. The embryonated eggs of experimentally infected hens were less susceptible to infection by inoculation than those of specific pathogen-free birds. Some chicks with maternal antibody were found to be infected at hatching and in these maternal antibody was not mycoplasmacidal. Indeed by protecting the embryo maternal antibody may have promoted hatching of infected chicks.

Maternal antibody to a respiratory isolate of Mycoplasma synoviae and contagious infection of chicks after hatching.

In chicks infected with Mycoplasma synoviae after hatching agglutinins were not detected for between 27 and 42 days. By this age the largely asymptomatic infection had spread extensively by contact. Detection of maternal agglutinins from hatching to 9 days in chicks from infected hens indicated that this should be considered as a diagnostic technique particularly where access to parent stock is limited.

Cloacal infection with Mycoplasma gallisepticum and the effect of inoculation with H120 infectious bronchitis vaccine virus.

Infectivity of an isolate of Mycoplasma gallisepticum of low virulence was studied in specific pathogen free chickens from 1 day old until after the onset of lay. Widespread cloacal infection developed and it was discussed in relation to the low serological response. The effects produced by inoculation of H120 infectious bronchitis vaccine virus and coming into lay were associated with changes in serological response and increased cloacal cultural recovery. The possibility of ascending cloacal infection giving rise to egg transmission was considered and compared with other routes whereby ovules may become infected.

Association of Mycoplasma synoviae with respiratory disease of broilers.

Serological and cultural investigation of broilers with respiratory disease implicated Mycoplasma synoviae infection in the syndrome which was characterised by variable mortality up to 20% at 6-8 weeks of age in association with Escherichia coli septicaemia. Preliminary experimental studies using specific-pathogen-free birds confirmed that the Mycoplasma synoviae concerned was of the respiratory type, first described in the USA as causing a rapidly spreading, persistent upper respiratory tract infection associated with production losses and in some flocks condemnations due to air sacculitis.

The prevalence of antibody of antibody to contagious caprine pleuropneumonia (Mycoplasma strain F38) in some wild herbivores and camels in Kenya.

Sera of 11 species of wild herbivores were tested for antibody to Mycoplasma strain F38 which causes contagious caprine pleuropneumonia (CCPP) in Kenya. Antibodies were found in buffalo (Syncerus caffer) (32%), impala (Aepyceros melampus) (10%) and camels (Camelus dromedarius) (49%) but not in bushbuck (Tragelaphus scriptus), eland (Taurotragus oryx), Grant's gazelle (Gazella granti), kongoni (Alcelaphus buselaphus cokei), oryx (Oryx beisa), Thomson's gazelle (Gazella thomsonii), waterbuck (Kobus defassa) and wildebeest (Connochaetus taurinus).

The effect of high passage Mycoplasma strain F38 on the course of contagious caprine pleuropneumonia (CCPP).

In comparison with an equal number of untreated controls, goats inoculated with high passage culture of mycoplasma strain F38 were significantly less susceptible to contact infection from CCPP cases.

The role of Mycoplasma strain F38 in contagious caprine pleuropneumonia (CCCP) in Kenya.

The results of a serological and cultural study of experimental and field cases of contagious caprine pleuropneumonia were consistent with an aetiological role for mycoplasma strain F38. This mycoplasma was isolated from 57 acute cases in 46 outbreaks of CCPP and from 87 experimental contact cases. Clinical data from experimental contact cases were assessed for comparison with field cases.