Effects of dietary fumonisin B1-containing culture material, deoxynivalenol-contaminated wheat, or their combination on growing barrows.

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.

Influence of aflatoxin and fumonisin B1-containing culture material on growing barrows.

Aflatoxin (AF)-contaminated and fumonisin B1 (FB1)-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 FB1/kg of feed (control); 2.5 mg of AF/kg of feed; 100 mg of FB1/kg of feed; or 2.5 mg of AF plus 100 mg of FB1/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 FB1 diets. The FB1 diet decreased feed consumption, and although body weight was numerically decreased, it was not statistically significant. Aflatoxin increased serum gamma-glutamyltransferase (GGT) activity and total iron concentration and decreased urea nitrogen concentration and unsaturated iron-binding capacity. The FB1-alone diet increased serum GGT activity, whereas the AF plus FB1 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 FB1 diet on body weight and hematologic measurements could be considered additive. However, the effect of the AF plus FB1 diet on cholinesterase and alkaline phosphatase activities was greater than additive and was a synergistic response. One pig in the FB1-diet group and 2 pigs in the combination-diet group died. Postmortem lesions in pigs of the FB1-diet group consisted of ascites and increased liver weight. Observations at necropsy for pigs of the AF plus FB1-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 FB1-diet group, but this was not consistent in the AF plus FB1-diet group. Cell-mediated immunity, as measured by mitogen-induced lymphoblastogenic stimulation index, was decreased in barrows of the AF and FB1-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 FB1 (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.

Effects of feeding fumonisin B1 present in Fusarium moniliforme culture material and aflatoxin singly and in combination to turkey poults.

Diets containing 200 mg fumonisin B1/kg of feed and .75 mg aflatoxin/kg of feed singly or in combination were fed to female turkey poults (Nicholas Large White) from day of hatch to 21 d of age. When compared with controls, 21-d body weight gains were reduced 10% by fumonisin B1, 39% by aflatoxins, and 47% by the combination. Relative weights (grams/100 g body weight) of the kidney and pancreas increased in poults fed the diet containing aflatoxins alone, whereas the relative weight of the liver decreased. Relative weights of the liver and pancreas increased in the poults fed the fumonisin diet. Relative weights of the kidney, pancreas, and gizzard increased in the poults fed the combination diet, whereas the relative weight of the liver decreased. Most serum constituents, hematology values, and activities of enzymes measured were altered in poults receiving the diets containing aflatoxins with or without fumonisin B1. No major histological lesions were observed in tissues from control poults or poults fed the diet containing fumonisin alone. Lesions associated with aflatoxins were only observed in the liver and occasionally in the kidney of poults fed the diets containing aflatoxins with or without fumonisin B1. The primary hepatic change was bile duct hyperplasia with some hepatocellular degeneration and necrosis and megalocytosis. Occasional necrotic and degenerating tubular epithelial cells were observed in the kidneys. The increased toxicity in poults fed the combination diet for most variables can best be described as additive, although some variables showed less than additive toxicity.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of the antibiotics lincomycin and tylosin on aflatoxicosis when added to aflatoxin-contaminated diets of growing swine.

Effects of dietary aflatoxin (AF) and the antibiotics lincomycin (L) and tylosin (T) were evaluated in growing crossbred pigs. Six barrows (3 replicates of 2 each, mean body weight 14.0 kg) per group were assigned to 1 of 6 treatment groups (for a total of 36): 0 mg L, 0 mg T, and 0 mg AF/kg of feed (control); 220 mg L/kg of feed (200 g/ton); 110 mg T/kg of feed (100 g/ton); 2.5 mg AF/kg of feed; 2.5 mg AF plus 220 mg L/kg of feed; 2.5 mg AF plus 110 mg T/kg of feed. Barrows were administered their respective diets for 28 days. Body weight, body weight gain, and feed consumption were reduced by the AF alone, the AF plus L, and the AF plus T treatments, compared with control, L, and T treatments. Altered serum biochemical or hematologic measurements induced by AF treatments included increased serum activities of alkaline phosphatase and gamma-glutamyltransferase, increased hematocrit, hemoglobin, RBC count, WBC count, and mean cell hemoglobin, decreased serum concentrations of albumin, cholesterol, inorganic phosphorus, unsaturated iron binding capacity, total protein, and urea nitrogen, and decreased lymphoblastogenic response. Liver weight was increased, and microscopic lesions were consistent with those observed in cases of aflatoxicosis. With some other minor exceptions for hematologic and immunologic variables, these data indicate that the feed antibiotics lincomycin and tylosin, when added to aflatoxin-contaminated diets, do not have beneficial or detrimental effects on aflatoxicosis in growing swine.

Influence of fumonisin B1, present in Fusarium moniliforme culture material, and T-2 toxin on turkey poults.

Diets containing 300 mg fumonisin B1 (FB1)/kg of feed and 5 mg T-2 toxin/kg of feed singly or in combination were fed to female turkey poults (Nicholas Large White) from day of hatch to 21 d of age. When compared with controls, 21-d body weight gains were reduced 21% by FB1, 26% by T-2, and 47% by the combination. the efficiency of feed utilization was adversely affected by FB1 and the combination of FB1 and T-2. Relative weights (grams/100 g BW) of the liver and gizzard were increased in poults fed the FB1 and the combination diets; whereas, the relative weight of the pancreas was increased in all treated groups. All poults were scored for oral lesions using a scale of 1 to 4 (1 = no visible lesions, 4 = severe lesions). Oral lesions were present in all poults fed the T-2 diet (average score of 3.29) or the combination diet (average score of 3.54). Serum concentration of cholesterol was decreased and lactate dehydrogenase activity was increased in poults fed the FB1 and combination diets. The activity of aspartate aminotransferase and the values for red blood cells, hemoglobin, and hematocrit were increased only in poults fed the combination diet. Inorganic phosphorus concentration was decreased only in poults fed the combination diet. The increased toxicity in poults fed the combination diet for most variables can best be described as additive, although some variables not altered by FB1 or T-2 singly were significantly affected by the combination, indicating that the combination may pose a potentially greater problem to the turkey industry than either of the mycotoxins individually.

Acute hepatic and renal toxicity in lambs dosed with fumonisin-containing culture material.

To examine the effects of acute exposure to fumonisin-containing culture material (FCCM), 15 crossbred wether lambs were dosed intraruminally with FCCM containing 0 (CONTROL, n = 3), 11.1 (LOW, n = 4), 22.2 (MED, n = 4), or 45.5 (HIGH, n = 4) mg of total fumonisins (B1, B2, and B3)/kg BW daily for 4 d. Blood samples were collected daily, and on d 11 lambs were killed and necropsied. Changes in serum constituents in fumonisin-treated lambs indicative of liver damage, included increased (P < .05) activities of alkaline phosphatase, gamma-glutamyl transferase, aspartate aminotransferase, and lactate dehydrogenase. Serum concentrations of cholesterol, triglycerides, urea nitrogen, and creatinine were also increased (P < .05) in lambs dosed with FCCM. Hemoglobin tended to increase (P = .07) and white blood cell count tended to decrease (P = .08) in HIGH lambs and activated partial thromboplastin time tended to decrease (P < .10) in lambs dosed with LOW and MED treatments. Mitogen-induced lymphocyte blastogenesis was not different (P = .14) among treatments. Feed intake markedly decreased (P < .01) following the first dosing of FCCM and continued to decline throughout the study. Ruminal VFA concentrations and pH tended to decrease (P < .10) at d 11 in treated lambs. Relative liver and kidney weights (g/100 g of BW) increased (P < .05) in fumonisin-treated lambs. Histiolgical examination revealved tubular nephrosis and mild hepatopathy in dosed lambs. Lambs receiving the HIGH treatment died on d 3, 4, 5, and 7 of the study and on d 9 one lamb on the MED treatment died.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration of ochratoxin A and T-2 toxin to growing swine.

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, gamma-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.

Effect of ochratoxin A on Salmonella-challenged broiler chicks.

Poultry products represent a significant reservoir of Salmonella typhimurium. Ochratoxin A, a mycotoxin and natural contaminant of poultry feedstuffs, produces detrimental effects on the immune and other systems of the broiler chick. Because poultry products are possible sources of S. typhimurium contamination that can potentially infect humans, there is a need to know whether ochratoxin A can alter the growth of Salmonella in poultry. We investigated the pathological alterations of young male broiler chicks by S. typhimurium in the presence (3.0 mg/kg) or absence of ochratoxin A in the diet. Ochratoxin A alone in the diet decreased the body weight and increased the relative organ weights of the liver, kidney, gizzard, spleen, pancreas, and proventriculus. It did not affect the heart and bursa of Fabricius. The mycotoxin altered the serum concentrations of proteins, enzymes, calcium and phosphate salts, normal tissue constituents, and catabolic metabolites in a pattern that would suggest damage to skeletal muscle, liver, kidney, pancreas, and bone. Birds fed diets containing ochratoxin A had microcytic and hypochromic erythrocytes and a decrease in phytohemagglutin- and concanavalin A-stimulated blastogenesis. Salmonella typhimurium alone had no affect on the variables measured except for a decrease in body weight. With the exception of an increase in mortality (13.2%, a significant synergistic interaction) and decrease in body weight, Salmonella in combination with ochratoxin A did not alter the values of the remaining variables measured from those measured in the ochratoxin A diet alone. Cecal colony count of S. typhimurium was not affected by treatment with ochratoxin A.

Influence of vitamin E on aflatoxicosis in growing swine.

Effects of dietary aflatoxin (AF) and supplemental vitamin E (d-alpha-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, gamma-glutamyltransferase, 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.

Comparison of two hydrated sodium calcium aluminosilicate compounds to experimentally protect growing barrows from aflatoxicosis.

Two formulations of hydrated sodium calcium aluminosilicate (HSCAS-1 and HSCAS-3), anti-caking agents for mixed feed, were added to the diets of growing barrows and were evaluated for their potential to diminish the clinical signs of aflatoxicosis. The experimental design consisted of 8 barrows (2 replicates of 4 each/treatment) assigned to 1 of the following 6 treatment diets (total of 48): 1) 0 g of HSCAS-1 or HSCAS-3 and 0 mg of aflatoxin (AF)/kg of feed (control); 2) 5 g HSCAS-1/kg of feed; 3) 5 g HSCAS-3/kg of feed; 4) 3 mg AF/kg of feed; 5) 3 mg AF plus 5 g HSCAS-1/kg of feed; or 6) 3 mg AF plus 5 g HSCAS-3/kg of feed. Barrows were maintained in indoor concrete-floored pens, with feed and water available for 28 days (from 8 to 12 weeks of age). Barrows were observed twice daily and weighed weekly, and blood samples were collected at day 28 for hematologic, immunologic, and serum biochemical measurements. At the termination of the study, barrows were euthanized and necropsied. Barrow body weight gains were diminished, compared to those of controls, by consumption of AF alone and both of the AF plus HSCAS diets; however, the AF plus HSCAS-1 and AF plus HSCAS-3 barrow body weight gains were significantly greater (P < 0.05) than those of the AF-alone barrows.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of a hydrated sodium calcium aluminosilicate to reduce the toxicity of aflatoxin and diacetoxyscirpenol.

A hydrated sodium calcium aluminosilicate (HSCAS) was incorporated into diets (.5%) containing 3.5 mg/kg aflatoxin (AF) and 5.0 mg/kg diacetoxyscirpenol (DAS) singly and in combination. Male broiler chicks received ad libitum access to their respective diets and water from 1 to 21 days of age. Body weight gains were significantly (P < .05) depressed by AF and DAS singly and a synergistic interaction occurred between AF and DAS for a further depression of body weight gains. Alterations in hematological and serum biochemical values, as well as serum enzyme activities, were observed for the AF and the AF and DAS combination. Additionally, a significant interaction occurred between AF and DAS for some biochemical values and enzyme activities. Adding HSCAS resulted in almost total protection against the effects caused by AF alone, limited protection against the combination, but no protection against the DAS alone. These findings indicate that HSCAS can diminish the adverse effects of AF but not of DAS.

Efficacy of zeolitic ore compounds on the toxicity of aflatoxin to growing broiler chickens.

Commercially available zeolitic ore compounds, when incorporated into the diets at 0.5%, were evaluated for their ability to reduce the deleterious effects of 3.5 mg aflatoxin/kg feed on growing broiler chickens from 1 day to 3 weeks of age. In a series of four experiments, the compounds used included the following: mordenite (particle size of -20 mesh; Zeomite); clinoptilolite (particle size of -20 mesh; Zeobrite); SC Zeolite (particle size of -20 mesh); and clinoptilolite (particle size of -35 mesh; Clino 1) or clinoptilolite (particle sizes of -20 plus +35 mesh; Clino 2). Results demonstrated that 0.5% Zeobrite, Clino 1, or Clino 2 added to aflatoxin-contaminated diets did not significantly (P < 0.05) diminish the toxicity of high concentrations of aflatoxin to growing broiler chicks. Zeomite mordenite ore reduced the toxicity of aflatoxin to growing chicks by 41%, as indicated by weight gains, liver weight, and serum biochemical measurements, which compares favorably with its in vitro binding capacity to aflatoxin. SC Zeolite reduced weight-gain toxicity of aflatoxin by approximately 29%.

Immunotoxicity of ochratoxin A to growing gilts.

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.

Changes in hematological, blood gas, and serum biochemical variables in broilers during exposure to simulated high altitude.

One-day-old broilers were reared until 35 days of age at both natural low (100 m) and simulated high altitude (2133 m) to assess the incidence and development of ascites syndrome. Clinical measurements were conducted at 7, 14, 21, 28, and 35 days of age. Birds reared at 2133 meters exhibited significantly (P less than or equal to 0.05) reduced body weights at 7 through 28 days of age. Total serum calcium and biochemical enzyme activities were found to be altered at 35 days of age. In addition, the high-altitude group had significantly (P less than or equal to 0.05) higher erythrocyte counts, hematocrits, and hemoglobin at 14, 21, 28, and 35 days of age and higher serum inorganic phosphorus at each weekly sample time than birds at the low altitude. Total mortality was 20.3% at 2133 meters and 4.6% at 100 meters. The incidence of ascites syndrome in the high-altitude group ranged from 16.6% to 61.1% during the 5-week experimental period.

Effects of a hydrated sodium calcium aluminosilicate on growing turkey poults during aflatoxicosis.

Effects of adding .5% of a hydrated sodium calcium aluminosilicate (HSCAS) to diets containing 1 or .5 mg aflatoxin (AF)/kg were determined in male turkey poults from 1 day to 3 wk of age. Body weight gains were significantly reduced by 51 and 19% in turkey poults fed 1 and .5 mg AF/kg, respectively; efficiency of feed utilization was not affected. There were no deaths in poults fed .5 mg AF/kg; however, the mortality rate was 88% in poults fed 1 mg AF/kg. The addition of .5% dietary HSCAS resulted in a 68% decrease in mortality to 28% for the 3-wk experimental period. Treatment-related changes in relative organ weights, hematological values, serum biochemical values, and enzyme activities were observed. The HSCAS in the absence of AF did not alter any of the parameters measured. The HSCAS diminished the adverse effects of AF on body weight gains, most relative organ weights, hematological values, serum biochemical values, and enzyme activities associated with .5 mg AF/kg, but not 1 mg AF/kg. These findings indicate that HSCAS may diminish many of the adverse effects of AF in an AF-sensitive species, the turkey.

Colonization control of lactose-fermenting Salmonella typhimurium in young broiler chickens by use of dietary lactose.

Inclusion of lactose in the diets of chickens has been determined to reduce cecal colonization with Salmonella typhimurium. We hypothesized, therefore, that dietary lactose may be a practical means for reducing the prevalence of Salmonella contamination of chicken products. Because some strains of Salmonella are atypical and ferment lactose, we investigated the effects of dietary lactose on cecal colonization with lactose-fermenting S typhimurium. Broiler chicks were inoculated intracloacally with Lac+ S typhimurium selected for resistance to novobiocin and rifampicin. The chicks also were inoculated orally with certain anaerobes that do not effectively inhibit colonization by S typhimurium, but do appear essential for lactose mediated inhibition of cecal colonization. Control chicks were not given dietary lactose, and chicks in the experimental group were fed a diet containing 7% lactose. Enumeration of Lac+ S typhimurium in cecal contents revealed dietary lactose to be effective at controlling this organism. Control was correlated with changes in cecal pH and increases in undissociated volatile fatty acids, especially propionic acid.

The individual and combined toxicity of kojic acid and aflatoxin in broiler chickens.

The individual and combined effects of kojic acid and aflatoxin were studied in male broiler chicks (Peterson x Hubbard). The experiment had a two by two factorial arrangement of treatments with dietary treatments of 0 and 2,500 mg kojic acid/kg feed and 0 and 2.5 mg aflatoxin/kg feed. The broilers were obtained at 1 day of age and housed in electrically heated batteries with feed and water available for ad libitum intake until they reached 3 wk of age. The toxicity of kojic acid was characterized by significant (P less than .05) reductions in body weight, the relative weight of the bursa of Fabricius, serum cholesterol concentration, and serum alkaline phosphatase activity, and by significant (P less than .05) increases in the relative weight of the pancreas, proventriculus, and gizzard, and serum concentrations of uric acid and triglycerides. Aflatoxicosis was characterized by significant (P less than .05) reductions in body weight, serum concentrations of total protein, albumin, cholesterol, and inorganic phosphorus, serum glutamic oxalacetic transaminase activity, and mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration. Significant (P less than .05) increases in the relative weight of the liver, kidney, spleen, pancreas, proventriculus, and heart, and the serum pyruvic transaminase activity were also caused by aflatoxin alone. The only significant (P less than .05) interaction between kojic acid and aflatoxin, which can best be described as antagonistic, was seen through an increase in mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. These data indicate that kojic acid is not an aflatoxin synergist at the levels used in the present study.

Cocontamination of swine diets by aflatoxin and diacetoxyscirpenol.

The effects of dietary aflatoxin (AF) and diacetoxyscirpenol (DAS), singly and in combination, were evaluated in growing crossbred barrows. The experimental design consisted of 4 treatments of 9 barrows each fed diets containing 1) 0 mg AF and 0 mg DAS/kg feed (control), 2) 2.5 mg AF/kg feed, 3) 2.0 mg DAS/kg feed, or 4) 2.5 mg AF + 2.0 mg DAS/kg feed for 28 days (10-14 weeks of age). Production performance, serum biochemical, hematologic, and pathologic measurements were made. Body weight and body weight gain were significantly decreased by each toxin but more so by the combination treatment. The effects were additive in nature. Liver and spleen weights, as percentages of body weight, were increased by the AF and AF + DAS treatments, and AF or AF + DAS treatments induced diffuse hepatocellular vacuolar change, early portal fibrosis, and early bile duct hyperplasia. Aflatoxin increased serum values of creatinine and gamma glutamyl transferase, cholinesterase, and alkaline phosphatase activities; increased packed cell volume and hemoglobin; and decreased urea nitrogen and total iron binding capacity. DAS reduced serum iron binding capacity. The AF + DAS treatment increased serum gamma glutamyl transferase and alkaline phosphatase activities, increased hemoglobin, and decreased serum iron binding capacity. Generally, the combination treatment could be described as additive or less than additive, with most of the effects attributable to AF. Under the conditions and parameters monitored in this study, AF and DAS had no synergistic toxic effects when incorporated into diets of growing barrows.