Search Results

You are looking at 1 - 7 of 7 items for

  • Author or Editor: George E. Rottinghaus x
  • Refine by Access: All Content x
Clear All Modify Search

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 determine whether cattle exposed to heat stress alone or heat stress while consuming endophyte-infected fescue (EIF) have lower wholeblood (WB) concentrations of glutathione (GSH).

Animals—10 Simmental cows.

Procedure—Cows were sequentially exposed to thermoneutral (TN; 2 weeks; 18 C, 50% relative humidity [RH]), heat stress (HS; 2 weeks; alternating 4-hour intervals at 26 and 33 C; 50% RH), and heat stress while consuming EIF (10 µg of ergovaline/kg/d; 2 weeks; HS + EIF). Blood samples were collected after each period and tested for GSH and oxidized glutathione (GSSG) concentrations.

Results—Feed consumption was similar when data were analyzed for time points at which WB concentrations of GSH or GSSG were determined. However, significant effects of treatment, cow, days exposed to heat, cow-by-treatment interaction, and treatment-bydays exposed to heat interaction were detected when data were considered simultaneously. Mean ± SD hematocrit for TN, HS, and HS + EIF were 35.3 ± 3, 33.3 ± 2, and 37.1 ± 3%, respectively. Mean WBGSH concentrations for TN, HS, and HS + EIF were 3.2 ± 0.65, 2.7 ± 0.62, and 2.4 ± 0.56 mmol/L of RBC, respectively. Reduced WBGSH concentrations were associated with reduced feed intake during the later part of each heat period.

Conclusion and Clinical Relevance—Decreased GSH and increased GSSG concentrations were evident during heat stress, especially when cattle consumed EIF. These were associated with reduced feed intake during heat stress. Heat stress, reductions in feed intake, and thermoregulatory effects of EIF may induce oxidative stress in cattle. (Am J Vet Res 2002;63:799–803)

Full 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

Abstract

Objectives

To determine the sequence of cardiovascular and blood gas changes induced by ingestion of fumonisin-containing culture material in swine and to examine the temporal relationship of these changes to plasma sphinganine and sphingosine concentrations.

Animals

12 healthy castrated pigs (38 to 50 kg).

Procedure

Pigs were instrumented to permit cardiovascular monitoring and collection of blood samples. Baseline values were obtained, and pigs were randomly assigned to 1 of 2 groups. Control pigs (n = 6) were fed a standard grower diet, whereas culture material that contained 20 mg of fumonisin B1/kg of body weight was added to the feed of treated pigs (n = 6) each day. Hemodynamic data, results of arterial and mixed venous blood gas analyses, and plasma sphinganine and sphingosine concentrations were recorded every 12 hours until treated pigs were euthanatized because of impending death from pulmonary edema.

Results

Sphinganine and sphingosine concentrations were increased in plasma of treated pigs within 24 hours of initial fumonisin exposure and continued to increase dramatically until euthanasia. Fumonisin-treated pigs had increased respiratory rate, mean pulmonary artery pressure, and pulmonary artery wedge pressure, along with decreased heart rate and cardiac output in the 12-hour period before euthanasia. Fumonisin-treated pigs also had systemic arterial hypotension, arterial and mixed venous hypoxemia, metabolic acidosis, decreased oxygen delivery, and increased oxygen consumption immediately before euthanasia.

Conclusions and Clinical Relevance

Fumonisin-induced pulmonary edema in swine is probably caused by acute left-sided heart failure. Onset of hemodynamic changes was associated with plasma sphinganine concentration ≥ 2.2 μM/L and plasma sphingosine concentration ≥ 1 µM/L (Am J Vet Res 1999;60:1292–1300)

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

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