sodium-nitrite and Swine-Diseases

A major concern during pesticide development and use is the impact on non-target species, such as raptors or domestic cats and dogs. Sodium nitrite and para-aminopropiophenone (PAPP) are two toxicants currently being studied for the control of invasive species, such as starlings and feral swine. When given to an animal these compounds oxidize hemoglobin, which renders it unable to carry oxygen resulting in methemoglobinemia. This study developed a method to estimate methemoglobin levels in mammals and birds by examining the efficacy of sodium nitrite to induce the conversion of hemoglobin to methemoglobin. Varying concentrations of sodium nitrite were added to aliquots of coyote, vole, feral swine, starling, and duck blood, collected from captive animals. The blood samples were analyzed spectrophotometrically to determine percent methemoglobin and digitally to determine red color values (RCV) associated with different methemoglobin levels. The avian and mammalian blood reached 100% methemoglobin levels at 200 mM and 15 mM sodium nitrite, respectively. All animals had similar RCV for a given percent methemoglobin. In conclusion, this study developed a procedure to quickly determine methemoglobin levels in mammals and birds. Furthermore, percent methemoglobin can be estimated with one standard curve from any animal species and an image of a blood spot. The technique will be useful during field studies, in agricultural areas, or in a veterinarian's office for the rapid diagnosis of methemoglobinemia in non-target animals that have eaten toxicants/baits or baited animals.

Topics: Animals; Animals, Wild; Arvicolinae; Bird Diseases; Colorimetry; Coyotes; Ducks; Methemoglobin; Methemoglobinemia; Sodium Nitrite; Spectrophotometry; Starlings; Swine; Swine Diseases

Isolants from swine and from humans representing serotypes 1, 2, 4, 8, and 10 of the Mycobacterium avium-Mycobacterium intracellulare complex were compared for heat tolerance in aqueous suspension. The most heat-resistant isolant found was a serovar 10 isolated from a human. This isolant was examined further to determine the rate of kill at various temperatures and pH's, the effect of meat protein and fat, and the effect of nitrite. Kill rates were not significant at 60 degrees C or below. Decimal reduction values were 4 min or less at 65 degrees C and 1.5 min or less at 70 degrees C. Kill rates were slightly higher at pH values of 6.5 and 7.0 than at 5.5 or 6.0. the water-soluble fraction of wiener emulsion did not alter kill rates, but the saline-soluble fraction protected the organism somewhat. Fat did not affect the survival of the organisms except to eliminate the protective effect of saline extract when the suspension contained 50% fat. The addition of sodium nitrite to the suspension did not alter the heat sensitivity of the organisms.

Topics: Animals; Hot Temperature; Humans; Hydrogen-Ion Concentration; Mycobacterium; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Sodium Chloride; Sodium Nitrite; Swine; Swine Diseases; Temperature