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Efficacy of an accelerated hydrogen peroxide disinfectant to inactivate porcine epidemic diarrhea virus in swine feces on metal surfaces
2017
In May of 2013, porcine epidemic diarrhea virus (PEDV) was detected in swine for the first time in North America. It spread rapidly, in part due to contaminated livestock trailers. The objective of this study was to test the efficacy of an accelerated hydrogen peroxide disinfectant for inactivating PEDV in the presence of feces on metal surfaces, such as those found in livestock trailers. Three-week-old barrows were inoculated intragastrically with 5 mL of PEDV-negative feces for the negative control, 5 mL of untreated PEDV-positive feces for the positive control, and 5 mL or 10 mL of PEDV-positive feces that was subjected to treatment with a 1:16 or 1:32 concentrations of accelerated hydrogen peroxide disinfectant for a contact time of 30 min at 20°C. These pigs served as a bioassay to determine the infectivity of virus following treatment. Rectal swabs collected from the inoculated pigs on days 3 and 7 post-inoculation were tested by using PEDV-specific real-time reverse transcription polymerase chain reaction and the proportion of pigs in each group that became infected with PEDV was assessed. None of the pigs used for the bioassay in the 4 treatment groups and the negative control group became infected with PEDV, which was significantly different from the positive control group (P < 0.05) in which all pigs were infected. The results suggest that the application of the accelerated hydrogen peroxide under these conditions was sufficient to inactivate the virus in feces found on metal surfaces.
Afficher plus [+] Moins [-]Effects of treatment of growing swine with aflatoxin and T-2 toxin
1990
Harvey, R.B. | Kubena, L.F. | Huff, W.E. | Corrier, D.E. | Rottinghaus, G.E. | Phillips, T.D.
Effects of dietary aflatoxin (AF) and T-2 toxin, singly and in combination, were evaluated in growing crossbred (Yorkshire X Landrace X Hampshire) pigs. The experimental design consisted of 4 treatment groups of 6 barrows each fed diets containing 0 mg of AF and T-2/kg of feed (controls; group 1), 2.5 mg of AF/kg of feed (group 2), 10 mg of T-2/kg of feed (group 3), or 2.5 mg of AF plus 10 mg of T-2/kg of feed (AF + T-2; group 4) ad libitum for 28 days (7 to 11 weeks of age). Production performance, and serum biochemical, and hematologic evaluations were made weekly. Body weight and body weight gain were depressed by all toxin treatments, but the effect of AF and T-2 toxin in combination was less than additive. Liver and kidney weights, as a percentage of body weight, were increased by AF treatment, and heart weight, as a percentage of body weight, was increased by T-2 treatment. Treatment with T-2 toxin induced necrotizing contact dermatitis on the snout, buccal commissures, and prepuce. Consumption of AF resulted in increased serum activities of alkaline phosphatase, aspartate transaminase, cholinesterase, and gamma-glutamyltransferase, and decreased serum concentrations of urea nitrogen, cholesterol, albumin, total protein, calcium, potassium, magnesium, and phosphorus. Consumption of T-2 toxin resulted in increased serum triglyceride concentration and decreased serum iron concentration. Treatment with AF induced lower serum unsaturated iron-binding capacity and high RBC count, PCV, hemoglobin concentration, WBC count, and prothrombin time. Treatment with T-2 toxin induced microcytic hypochromic anemia, increased numbers of circulating metarubricytes and decreased absolute numbers of lymphocytes. Hepatocellular lesions in barrows of the AF and the AF plus T-2 groups (2 and 4, respectively) were compatible with aflatoxicosis. When fed in combination, each toxin appeared to have a sparing action on certain effects of the other, and the responses elicited were either additive or less than additive.
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