ABSTRACT
Ticks represent a threat to animal health worldwide and are considered the second most important vectors of human diseases. The main method of control of ticks has been the usage of chemical products; however, the use of acaricides has resulted in some serious drawbacks such as acaricide-resistant ticks and environmental pollution. As a result the use of immunological control using tick proteins is suggested as an alternative to control tick populations. The protocols used to test the ticks to antigens, needs a complementary method that would allow control to be carried out in external conditions. In this context, the use of the in vitro capillary feeding represents a low cost alternative to test candidate antigens allowing to get important data on the protective effect during interactions between antigenantibody. In order to evaluate the effect in biological parameters of female R. microplus ticks by artificial feeding with bovine blood containing anti-subolesin peptide IgG's obtained at different times after immunization. Results of this study showed the effect on weight of ticks and oviposition due to antibodies obtained at weeks 3, 5 and 7 after immunization. The results proved that anti-subolesin peptide IgG´s at week 7 demonstrated better effect reducing tick weight by 45% and oviposition by 71% (P<0.05) with respect to tick fed on blood with preimmune serum. These results strongly suggested that the negative effects in cattle tick biological parameters were the result of the protective antibodies against subolesin peptide. Finally, the artificial feeding of ticks should be used to evaluate antigen-specific antibodies avoiding external factors.
ABSTRACT
A case-control study was carried out for determining epidemiological patterns at the beginning of the Mexican campaign against bovine tuberculosis (BTB) in the State of Tamaulipas, Mexico, bordering the United States of America. From January 1995 to March 1998, 599 direct tissue smears of cattle from routine slaughterhouse inspection were analyzed for the presence of Mycobacterium bovis acid-fastness with Ziehl-Neelsen stain. BTB status was associated with year of diagnosis, age, breed, geographical origin of cattle, and type of slaughterhouse using the odds ratio (OR) (95 percent confidence level). The prevalence at slaughterhouse surveillance was 15.36 percent, which was considerably higher in 1995 (41.38 percent, OR=5.78, P<0.0001), in comparison with 8.09 percent, 14.42 percent, and 10.14 percent for the years 1996, 1997, and 1998, respectively. BTB was associated with cattle from the State of Tamaulipas (19.73 percent, OR= 4.438, P=0.01), adult cattle (19.13 percent, OR=2.19, P<0.0001), Bos taurus (22.54 percent, OR=2.135, P<0.0001) and B. taurus x B. indicus cross bred animals (29.31 percent, 2.769, P<0.0001), and cattle slaughtered at federal inspected abattoir (17.58 percent, OR=1.23, P<0.0001).
O estudo foi realizado para determinar os padrões epidemiológicos no início da campanha mexicana contra a tuberculose bovina (BTB), no Estado de Tamaulipas, fronteira com os Estados Unidos da América. De janeiro de 1995 a março de 1998, 599 amostras de tecidos bovinos, obtidas em inspeção de rotina em abatedouros, foram analisadas para a presença de Mycobacterium bovis, fixadas em corante Ziehl-Neelsen. O status BTB foi associado ao ano do diagnóstico, idade, raça e origem geográfica do bovino utilizando a razão de probabilidade (OR) (com intervalo de confiança de 95 por cento). A prevalência no abatedouro sob inspeção foi de 15,36 por cento, consideravelmente maior em 1995 (41,38 por cento, OR=5,78), P<0,0001) em relação a 8,09 por cento, 4,42 por cento e 10,14 por cento para 1996, 1997 e 1998, respectivamente. Houve associação entre BTB e animais provenientes do estado de Tamaulipas (19,73 por cento; OR=0.438; P=0.01), idade adulta (19,13 por cento; OR=2,19; P<0,0001), Bos taurus (22,54 por cento; OR=2,135; P<0,0001) e cruzamentos B. taurus x B. indicus (29,31 por cento; 2,769; P<0,0001), e animais abatidos em abatedouros federais inspecionados (17,58 por cento; OR=1,23; P<0,0001).
Subject(s)
Animals , Cattle , Communicable Disease Control , Tuberculosis, Bovine/epidemiology , Cattle , Mexico/epidemiologyABSTRACT
An immunobinding dot-blot assay (DBA) was developed on nitrocellulose paper for the serodiagnosis of human cysticercosis, using Cysticercus cellulosae as antigen. The DBA had an immunological sensitivity of 0.08 mg of antigen protein/ml; however, it showed cross-reactions with antigens of adult Taenia solium and Echinococcus granulosus, but not with Toxoplasma gondii and Entamoeba histolytica antigens. An enzyme-linked immunosorbent assay (ELISA) was used as the gold standard for obtaining the diagnostic validity of the DBA, giving 84.61%, 100.00%, 100.00% and 97.98% for epidemiological sensitivity, epidemiological specificity and positive and negative predictive values, respectively. There were no statistical differences between the two tests (P < 0.05, kappa = 0.907). This study showed that DBA is an alternative method for the serodiagnosis of human cysticercosis.
