Antibody detection against Borrelia burgdorferi in horses located in the suburban areas of Monterrey, Nuevo León.

The aim of the present study was to determine the presence of Borrelia burgdorferi antibodies in horses from the metropolitan area of Monterrey, Nuevo León, México. Blood serum was obtained from a total of 100 horses residing at different counties in the area. From each animal data was obtained on age, sex, county of residence, presence of ectoparasites and clinical signs. All sera samples were analyzed by indirect immunofluoresence and the sera that resulted positive to this test was analyzed by Western blot. The serological test yielded 34 positive sera at 1:64 dilution, and from them 6 were positive at 1:128 dilution, 3 at 1:256, and only one at 1:512. Confirmation of the infection by Western blot was obtained only in the sample positive at the 1:512 dilution. These results shown a low frequency of seropositivity to B. burgdorferi of the horses in the area, confirming previous studies indicating that in northeast Mexico Lyme disease is present in different animal species.

Serological survey of canine borreliosis.

Lyme disease or Borreliosis, a tick-borne disease caused by Borrelia burgdorferi, has been described recently in dogs. A total of 850 blood samples were obtained from dogs in the metropolitan area of Monterrey, Mexico. An indirect immunofluorescent assay (IFA) was used to detect antibodies against Borrelia burgdorferi, the etiologic agent of Lyme disease in human beings. The 16% (136) of these dogs had positive results. These findings suggest that exposition to this microorganism is common in dogs in this area and that this disease is of importance to veterinarians.

Serological activity of white-tail deer against several species of Brucella.

In Mexico, brucellosis is a widely distributed disease of domesticated ruminants, but its frequency in wild ruminants has not been documented. Since northeast Mexico is the main distribution area of white-tailed deer and has been reported as an area positive for brucellosis in domesticated species, the present study was conducted in order to determine serological activity against several species of the genus Brucella in white-tailed deer. A total of 208 sera of white-tailed deer were collected during the springs of 1994 and 1995 in the north part of the states of Nuevo León and Coahuila. Each serum was analyzed for the detection of antibodies against two smooth (B. abortus and B. melitensis) and one rough (B. ovis) species of the genus Brucella. The serological tests used for the determination of the presence of antibodies against Brucella were card and plate agglutination for B. abortus, plate agglutination and rivanol precipitation for B. melitensis, and agar gel immunodiffusion for B. ovis. Each assay had positive and negative controls. None of the analyzed samples was found to be positive, and only two sera showed partial plate agglutination against B. melitensis at a dilution of 1:25; however, at higher dilutions and to the rivanol precipitation test the same samples were negative. Therefore, the percentage of positive sera was estimated at 0% (0/208). This result makes evident the absence of positive white-tailed deer against Brucella in the sampled area, despite that this disease is considered present in domesticated species. Therefore, white-tailed deer does not have, at the present time, an important role for the dispersion of the disease. The same result has been reported in other countries.

Environment, incidence, aetiology, epizootiology and immunoprophylaxis of soil-borne diseases in north-east Mexico.

Within the framework of an extensive research programme, the socio-economic and environmental conditions which influence the emergence of soil-borne diseases in north-eastern Mexico were analysed. Furthermore, specimens collected from carcasses in the field were bacteriologically examined and the causal organisms of soil-borne diseases differentiated by means of gas chromatographic analysis of their metabolic products and the long-chained fatty acids contained in the cell. With experimental clostridial vaccines prepared with the Goettingen Bioreactor Technique, trials to protect cattle and guinea-pigs against gas gangrene were carried out. It was found that the farm structure and the dry climate as well as the specific soil conditions and plant cover favour the emergence of soil-borne diseases. Causal organisms B. anthracis, C. perfringens, C. sordellii, C. haemolyticum, C. chauvoei/septicum, C. novyi A, C. botulinum and site-specific field strains of clostridia were detected. Experimental site-specific vaccines proved to be highly efficient in protecting cattle and guinea pigs.

Detection of Borrelia burgdorferi DNA in human skin biopsies and dog synovial fluid by the polymerase chain reaction.

The polymerase chain reaction was used to amplify DNA sequences of the etiologic agent of Lyme disease, Borrelia burgdorferi, and was applied to the detection of the spirochete in humans and dogs. Oligonucleotide primers used in the reaction flank a 244-base-pair representing part of the variable region V4 of the B. burgdorferi 16S rRNA from biopsies of patients with acrodermatitis, and in synovial fluid from a dog with arthritis. These data suggest the presence of the disease in our state.