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  • Author or Editor: Leon F. Kubena x
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Summary

Effects of dietary aflatoxin (af) and supplemental Vitamin E (d-α-tocopherol) were evaluated in growing crossbred pigs. Nine barrows (3 replicates of 3 each, mean body weight, 14.0 kg) per group were assigned to 1 of 4 treatment groups (for a total of 36 barrows): 0 IU of supplemental vitamin E and 0 mg of af/kg of feed (control); 2,400 IU of vitamin E divided into equal doses and administered im on days 1 and 16; 2.5 mg of af/kg of feed; or 2.5 mg of af/kg of feed plus 2,400 IU of vitamin E administered similarly to treatment 2. Barrows were administered their respective treatment for 32 days. Evaluations were made for group production performance and for serum biochemical, immunologic, hematologic, pathologic, serum and tissue tocopherol, and serum retinol variables. Body weight was reduced by af-alone and af plus vitamin E treatments, compared with control and vitamin E-alone treatments. Liver weight was increased for the af alone-treated and the af plus vitamin E-treated barrows, compared with control barrows. The af alone-treated barrows had alterations in:serum values of alkaline phosphatase, γglutamyltransferase, albumin, glucose, phosphorus, calcium, cholesterol, total iron, unsaturated iron-binding capacity, total iron-binding capacity, and urea nitrogen; RBC numbers, hematocrit, hemoglobin concentration, and prothrombin time; and mitogen-induced lymphoblastogenic responses. With the exception of some slight ameliorating effects on hematologic measurements, supplemental treatment with vitamin E did not prove beneficial against the toxicosis-associated af treatment. The af alone-treated barrows had decreased serum tocopherol and retinol concentrations, compared with control and pretest values, and decreased tocopherol concentration in cardiac tissue. High parenterally administered doses of vitamin E did not have sparing effect on af-induced reductions of serum tocopherol or retinol concentration; however, compared with pretest values, serum tocopherol concentration was increased by vitamin E-alone treatment. Tocopherol concentration in cardiac tissue of the af plus vitamin E-treated barrows was increased over that of the af alone-treated barrows, indicating an ameliorating effect on af-induced tissue concentrations reductions. These data indicate that vitamin E may not have a sparing effect on af-induced toxicosis and that af may reduce serum retinol and serum and tissue tocopherol concentrations.

Free access
in American Journal of Veterinary Research

SUMMARY

Ochratoxin A (oa) was incorporated in the diets of growing gilts (mean body weight, 20.1 kg) at a concentration of 2.5 mg of oa/kg of feed and was fed continuously for 35 days. Humoral and cell-mediated immunologic measurements were evaluated to determine the effects of oa on immune function in swine. Cutaneous basophil hypersensitivity to phytohemagglutinin (pha), delayed hypersensitivity to tuberculin, pha-induced lymphocyte blastogenesis, interleukin-2 production, total and isotype immunoglobulin concentrations, antibody response to chicken rbc, and macrophage activation were used to evaluate immune function. Gilts treated with oa had reduced cutaneous basophil hypersensitivity response to pha, reduced delayed hypersensitivity to tuberculin, decreased stimulation index for lymphoblastogenesis, decreased interleukin-2 production when lymphocytes were stimulated with concanavalin A, and decreased number and phagocytic activity of macrophages. Differences were not observed for total and isotype immunoglobulin concentrations, or humoral hemagglutination (chicken rbc) titer. These data indicate that oa may suppress cell-mediated immune response in growing swine.

Free access
in American Journal of Veterinary Research

SUMMARY

Aflatoxin (af)-contaminated and fumonisin B1 (fb 1)-contaminated (culture material from Fusarium moniliforme) diets were fed singly and in combination to growing cross-bred barrows. Six barrows (3 replicates of 2 each; mean body weight, 17.5 kg) per group were fed: 0 mg of af and 0 mg of fb 1/kg of feed (control); 2.5 mg of af/kg of feed; 100 mg of fb 1/kg of feed; or 2.5 mg of af plus 100 mg of fb 1/kg of feed for 35 days. The effects on production performance, serum biochemical, hematologic, immunologic, and pathologic measurements were evaluated. Body weight, gain, and feed consumption were significantly (P < 0.05) decreased by af and af plus fb 1 diets. The fb 1 diet decreased feed consumption, and although body weight was numerically decreased, it was not statistically significant. Aflatoxin increased serum γ-glutamyltransferase (GGT) activity and total iron concentration and decreased urea nitrogen concentration and unsaturated iron-binding capacity. The fb 1-alone diet increased serum GGT activity, whereas the af plus fb 1 diet increased serum aspartate transaminase, Cholinesterase, alkaline phosphatase, and GGT activities, increased rbc count, triglycerides, and total iron concentrations, and decreased unsaturated iron-binding capacity and urea nitrogen concentration. For the most part, the effects of the af plus fb 1 diet on body weight and hematologic measurements could be considered additive. However, the effect of the af plus fb 1 diet on cholinesterase and alkaline phosphatase activities was greater than additive and was a synergistic response. One pig in the fb 1-diet group and 2 pigs in the combination-diet group died. Postmortem lesions in pigs of the fb 1-diet group consisted of ascites and increased liver weight. Observations at necropsy for pigs of the af plus fb 1-diet group consisted of hydrothorax, ascites, pulmonary edema, gastric erosions and ulceration, and increased liver and spleen weights. The af diet increased relative liver weight and resulted in liver that was pale, rubbery, and resistant to cutting. Histologic lesions consisted of hepatic necrosis or degeneration, or both, with variable degrees of bile duct proliferation in barrows of the af-diet groups. Renal tubular nephrosis was observed in barrows of the fb 1-diet group, but this was not consistent in the af plus fb 1-diet group. Cell-mediated immunity, as measured by mitogen-induced lymphoblastogenic stimulation index, was decreased in barrows of the af and fb 1-diet groups, and values in barrows given the combination diet were significantly decreased from those in barrows given the single toxin diets. It was concluded that af and fb 1 (from culture material), singly or in combination, can adversely affect clinical performance, serum biochemical, hematologic, and immunologic values and induce lesions in growing barrows. For most of the variables we evaluated under our study conditions and dosages of toxins, measurements were affected more by the combination diet than by either single toxin diet, and the toxic responses could be described as additive or more than additive, particularly for induction of liver disease.

Free access
in American Journal of Veterinary Research

Summary

Effects of dietary ochratoxin A (oa) and T-2 toxin, fed singly and in combination, were evaluated in growing crossbred pigs. Thirty-six barrows (3 replicates of 3 for each of 4 treatment groups, mean body weight, 18.0 kg) were fed: 0 mg of oa and 0 mg of T-2/kg of feed (control); 2.5 mg of oa/kg of feed; 8.0 mg of T-2/kg of feed; or 2.5 mg of oa plus 8.0 mg of T-2/kg of feed for 30 days. Production performance, serum biochemical, hematologic, immunologic, and pathologic evaluations were made. Body weight and body weight gain were decreased by all toxin treatments, but the combination toxin treatment reduced weight gain more than did either of the toxins administered singly and could be considered additive. Liver weight was decreased by combination treatment, whereas kidney weight was increased by oa treatment. Ochratoxin decreased serum cholesterol, inorganic phosphorus, and alkaline phosphatase values; reduced mean cell volume, hemoglobin concentration, and macrophage phagocytosis; and increased creatinine and total protein values. Consumption of T-2 toxin reduced hemoglobin and serum alkaline phosphatase values. The combination treatment decreased serum cholesterol, γ-glutamyltransferase, alkaline phosphatase, mean cell volume, hematocrit, and hemoglobin values, as well as lymphoblastogenesis and phagocytosis, and increased serum creatinine concentration. We concluded that oa and T-2, singly or in combination, can affect clinical performance, serum biochemical, hematologic, and immunologic values, and organ weights of growing barrows. Although some analytes were affected more by the combination than by either toxin alone, the interactions could best be described as additive, not synergistic.

Free access
in American Journal of Veterinary Research

Summary

Hydrated sodium calcium aluminosilicate (hscas), an anticaking agent for agricultural feeds, was added to aflatoxin (af)-contaminated diets of 3 lactating dairy cows and evaluated for its potential to reduce aflatoxin M1 (afm 1) residues in milk. During phase I, cows were fed alternating diets that consisted of 200 μg of af/kg of feed for 7 days, 0.5% hscas plus 200 μg of af/kg of feed for 7 days, and feed with the hscas removed for a final 7 days. The afm 1 milk concentrations from the intervals with hscas added to diets were compared with those times when hscas was absent. The presence of 0.5% hscas in feed containing 200 μg of af/kg reduced afm 1 secretion into the milk by an average of 0.44 μg/L (from pretreatment of 1.85 μg/L to 1.41 μg/L with hscas, a 24% reduction). Following a 10-day period of noncontaminated feed consumption and no afm 1 residues in the milk, phase II of the study was begun. The same experimental design as phase I was used, but the dosages of hscas and af were changed to 1.0% and 100 μg/kg of feed, respectively. The addition of 1.0% hscas in feed containing 100 μg of af/kg decreased afm 1 content in the milk by an average of 0.40 μg/L (from a pretreatment of 0.91 μg/L to 0.51 μg/L when hscas was present, a 44% reduction). These findings suggest that hscas, a high-affinity sorbent compound for af in vitro, is capable of reducing the secretion of afm 1 into milk.

Free access
in American Journal of Veterinary Research

SUMMARY

Hydrated sodium calcium aluminosilicate (hscas), an anticaking agent for mixed feed, was added to the diets of growing wethers (mean body weight, 34.0 kg) and was evaluated for its ability to diminish the clinical signs of aflatoxicosis. The experimental design consisted of 4 treatment groups of 5 wethers each, consuming concentrations of 0 g of hscas and 0 g of aflatoxin (af)/kg of feed (control; group 1); 20 g of hscas/kg (2.0%; group 2), 2.6 mg of af/kg (group 3); or 20 g of hscas (2.0%) plus 2.6 mg of af/kg (group 4). Wethers were maintained in indoor pens, with feed and water available ad libitum for 42 days. Lambs were observed twice daily and weighed weekly, and blood samples were obtained every 2 weeks for hematologic and serum biochemical analyses and for measurement of mitogen-induced lymphocyte-stimulation index. At the termination of the study, wethers were euthanatized and necropsied. Body weight gain was diminished significantly (P < 0.05) by consumption of 2.6 mg of af/kg of feed, whereas body weight of lambs consuming hscas plus af did not differ from that of control wethers. The af-alone treatment increased serum aspartate transaminase and γ-glutamyltransferase activities, prothrombin time, and cholesterol, uric acid, and triglyceride values and decreased albumin, glucose, and urea nitrogen values, and urea-to-creatine ratio. A 27% decrease in lymphocyte stimulation index, increased spleen weight (as a percentage of body weight), and decreased liver weight were induced by af-alone treatment. Results indicate that hscas may be a high-affinity sorbent for af, that 2.6 mg of af/kg of feed induces signs of aflatoxicosis in growing wethers, that lambs may not be as resistant to the effects of af as previously thought, that 2.0% hscas can substantially reduce the toxic effects of 2.6 mg of af/kg, and that sorbent compounds may offer a novel approach to the preventive management of aflatoxicosis in livestock.

Free access
in American Journal of Veterinary Research

SUMMARY

Effects of dietary aflatoxin (af) and T-2 toxin, singly and in combination, were evaluated in growing crossbred (Yorkshire × Landrace × 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 γ-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.

Free access
in American Journal of Veterinary Research

Abstract

Objective

To examine the toxic effects of fumonisin B1 (FB1(-containing culture material and deoxynivalenol (DON)-contaminated wheat diets on barrows.

Animals

24, 7-week-old crossbred barrows allotted to 4 equal groups of 3 replicates of 2 barrows/replicate.

Procedure

Barrows were fed diets for 28 days that were formulated as follows: no additional FCM or DON/kg of feed (control); 100 mg FB1/kg of feed; 5 mg DON/kg of feed; or 100 mg FB1 plus 5 mg DON/kg of feed. Body weight and feed consumption were monitored weekly. On day 28, blood samples were obtained for serum biochemical, hematologic, and immunologic measurements. On day 29, barrows were euthanatized and necropsies were performed.

Results

Analyzed mycotoxin content of diets were: none detected (control); 47 mg of FB1/kg of feed (FB1 diet); 4.5 mg of DON/kg of feed (DON diet); and 56 mg of FB1 and 3.7 mg of DON/kg of feed (FB1 plus DON diet). Differences were detected among groups of barrows for clinical performance, serum biochemical analytes, immunologic response, and histopathologic lesions.

Conclusions

Combining FB1-containing material and DON-contaminated wheat in the diets of growing barrows induces a more toxic response than that induced by either toxin singly. For many variables, the response could be described as additive; however, for some variables, responses were interactive in a greater-than-additive manner.

Clinical Relevance

Caution should be exercised when formulating swine diets that could contain FB1 and DON, because the condition induced by their combination is more severe than that predicted for each mycotoxin's toxicity. (Am J Vet Res 1996;57:1790–1794)

Free access
in American Journal of Veterinary Research