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Biomedical subjects

L F Kubena

Publications and source records attributed to L F Kubena.

At least 19 recordsLinked to original sources
PubMed1992

Efficacy of hydrated sodium calcium aluminosilicate to reduce the individual and combined toxicity of aflatoxin and ochratoxin A.

A 2 x 2 x 2 factorial arrangement of treatments consisting of dietary aflatoxin (3.5 micrograms/g), ochratoxin A (2.0 micrograms/g), and hydrated sodium calcium aluminosilicate (HSCAS, .5%) was used to evaluate the individual and combined effects of these treatments. There were six replicate pens of 10 broilers per pen for each of the eight treatments. The broilers were maintained on these treatments from 1 day to 3 wk of age with feed and water available for ad libitum intake. Aflatoxin and ochratoxin A each significantly decreased body weight, serum protein, albumin, and cholesterol and increased the relative weight of the liver, kidney, and proventriculus. Aflatoxin increased the relative weight of the heart and decreased serum aspartate aminotransferase activity and ochratoxin A increased serum uric acid. The toxicity resulting from the combination of aflatoxin and ochratoxin A was more severe than when either of these mycotoxins were present alone. Addition of HSCAS alone did not alter any of the parameters evaluated. The HSCAS reduced the toxicity of aflatoxin, but had little effect on either the toxicity of ochratoxin A alone or the toxicity resulting from the combination of aflatoxin and ochratoxin A.

Aluminum Silicates↗
PubMed1992

Toxicological evaluation of aflatoxin and cyclopiazonic acid in broiler chickens.

The individual and combined effects of aflatoxin (AF) and cyclopiazonic acid (CPA) were evaluated in day-old Petersen x Hubbard broiler chickens to 3 wk of age. Treatments were arranged in a 2 x 2 factorial with levels of 0 and 3.5 mg AF/kg of feed, and 0 and 50 mg CPA/kg of feed. Production performance, serum biochemistry, and gross pathological observations were evaluated. Body weight gain was significantly (P less than .05) reduced by AF, CPA, and the AF-CPA combination at the end of 3 wk. Aflatoxin significantly increased the relative weight of the kidney and serum concentration of blood urea nitrogen and decreased serum concentrations of protein, albumin, cholesterol, phosphorus, and the activity of lactate dehydrogenase. The toxicity of CPA was expressed through increased relative weights of the liver, kidney, and proventriculus, increased levels of uric acid and cholesterol, and decreased serum phosphorus. The activity of AF-CPA combination was characterized by increased relative weight of the liver, kidney, pancreas, and proventriculus, decreased concentrations of serum albumin and phosphorus, increased concentrations of serum glutamic oxalacetic transaminase and blood urea nitrogen, and decreases in the relative weight of the bursa of Fabricius. Post-mortem examination revealed that the chickens fed CPA and the AF-CPA combination had thickened mucosa and dilated proventricular lumens, hard fibrotic spleen, and atrophy of the gizzard. The data from the present study demonstrate that both AF and CPA alone and the AF-CPA combination can limit broiler performance and adversely affect broiler health. In most cases the effects of AF and CPA were additive.

Aflatoxins↗
PubMed1992

Fermentation of [14C]lactose in broiler chicks by cecal anaerobes.

Volatile fatty acids and lactic acid were products of [14C]lactose metabolism in 10-day-old broiler chicks. The [14C]lactose and unlabeled lactose were given to chicks in combination with cultures of cecal anaerobes (direct fed microbials) from adult broiler chickens. Aliquots of these cecal anaerobes had been used previously to reduce Salmonella typhimurium colonization in broiler chicks. In the current study, chicks were treated with anaerobes and anaerobes plus lactose on the day of hatch. Chicks given lactose plus anaerobes also received unlabeled lactose in the drinking water. Chicks in all treatment groups received [14C]lactose on Day 10 posthatch. After 5 h, most of the radiolabel was detected in the foregut and intestine. Significantly lower concentrations of [14C]lactic acid were detected in the serum and foregut of chicks given anaerobes and anaerobes plus lactose than in the similar samples from control chicks. Additionally, significantly less [14C]lactic acid was detected in the feces of chicks treated with anaerobes plus lactose than in feces from control chicks and chicks receiving only anaerobes. Significant differences in the total content of volatile fatty acids and lactic acid were detected in the serum, liver, intestine, and ceca of chicks treated with anaerobes or anaerobes plus lactose. These data indicate that cecal flora utilize lactose to produce volatile fatty acids and lactic acid.

Animals↗
PubMed1992

Reference serum biochemical values for emus and ostriches.

Reference serum biochemical values were determined in blood samples from 15 male, 18 female, and 4 unsexed emus (Dromaius novaehollandiae) 1 to 48 months old. Serum biochemical values also were obtained for 19 male, 26 female, and 4 unsexed ostriches (Struthio camelus) 1 to 60 months old. Parametric (mean +/- 2 SD) and non-parametric (fifth to 95th percentile) reference ranges and linear trends as influenced by age were determined for enzyme activities and concentrations of glucose, inorganic phosphate, BUN, uric acid, creatinine, triglyceride, cholesterol, total protein, and albumin. Species differences for all analytes, except cholesterol and inorganic phosphate concentrations, were detected. Creatine kinase values in ostriches were higher than those in emus. There were no linear relationships between age and analyte values in emus, and sex did not significantly (P < 0.05) affect the values in emus. Analyte values in ostriches tended to increase with age, but cholesterol, creatine kinase, inorganic phosphate, and alkaline phosphatase concentrations decreased with age. Glucose, triglyceride, gamma-glutamyltransferase, and cholinesterase concentrations in ostriches were not linearly associated with age. Age had a greater effect on the analyte values of female ostriches than it did on male ostriches. Concentrations generally increased with age in female ostriches, except for cholesterol, cholinesterase, inorganic phosphate, and alkaline phosphatase concentrations, which decreased with age.

Aging↗
PubMed1992

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.

Animals↗
PubMed1991

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.

Aflatoxins↗
PubMed1991

Decreased Salmonella colonization in turkey poults inoculated with anaerobic cecal microflora and provided dietary lactose.

The effect of intracloacal inoculation with anerobic cultures of cecal microflora and addition of lactose to the feed on Salmonella senftenberg cecal colonization was evaluated in turkey poults. One-day-old poults were divided into four groups and provided 1) no anaerobic cultures, no lactose (control), 2) anaerobic cultures, 3) 5% lactose in the feed, or 4) anaerobic cultures and lactose. All groups were challenged orally with 10(6) S. senftenberg at 3 days of age. Salmonella senftenberg growth in the cecal contents was significantly decreased (P less than .05) at 10 and 30 days of age in both trials and at 20 days of age in Trial 1 in each of the three treatment groups as compared with the controls. On Day 30, the number of poults that were positive for Salmonella cecal culture was significantly decreased (P less than .01) in each of the treatment groups compared with the controls. Protection against Salmonella colonization was similar in the treatment groups inoculated with anaerobic cultures or provided dietary lactose. Combined treatment with anaerobic cultures of cecal microflora and provision of dietary lactose resulted in a level of protection against colonization equal to or higher than did either of the two treatments administered separately.

Animals↗
PubMed1991

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.

Aflatoxins↗
PubMed1991

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.

Aluminum Silicates↗
PubMed1991

Effects on aflatoxin M1 residues in milk by addition of hydrated sodium calcium aluminosilicate to aflatoxin-contaminated diets of dairy cows.

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 (AFM1) residues in milk. During phase I, cows were fed alternating diets that consisted of 200 micrograms of AF/kg of feed for 7 days, 0.5% HSCAS plus 200 micrograms of AF/kg of feed for 7 days, and feed with the HSCAS removed for a final 7 days. The AFM1 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 micrograms of AF/kg reduced AFM1 secretion into the milk by an average of 0.44 micrograms/L (from pretreatment of 1.85 micrograms/L to 1.41 micrograms/L with HSCAS, a 24% reduction). Following a 10-day period of noncontaminated feed consumption and no AFM1 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 micrograms/kg of feed, respectively. The addition of 1.0% HSCAS in feed containing 100 micrograms of AF/kg decreased AFM1 content in the milk by an average of 0.40 micrograms/L (from a pretreatment of 0.91 micrograms/L to 0.51 micrograms/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 AFM1 into milk.

Aflatoxin M1↗
PubMed1991

Diminution of aflatoxin toxicity to growing lambs by dietary supplementation with hydrated sodium calcium aluminosilicate.

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 less than 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 gamma-glutamyltransferase activities, prothrombin time, and cholesterol, uric acid, and triglyceride values and decreased albumin, glucose, and urea nitrogen values, and urea-to-creatine ratio.(ABSTRACT TRUNCATED AT 250 WORDS)

Aflatoxins↗
PubMed1990

Impact of L-phenylalanine supplementation on the performance of three-week-old broilers fed diets containing ochratoxin A. 1. Effects on body weight, feed conversion, relative organ weight, and mortality.

An experiment with a completely randomized 2-by-3 factorial design was used to study the effects of ochratoxin A (OA; 0 and 4 mg of OA per kg) and supplemental L-phenylalanine (Phe; .0%, .8%, and 2.4% of Phe) in the diets of 3-wk-old broilers. Diets based on ground yellow corn and dehulled soybean meal were fed from Day 1 to 3 wk of age. A total of 240 male Hubbard-by-Hubbard broilers were randomly placed in battery brooders with 10 birds per pen. Each treatment was replicated 4 times. The parameters measured included mortality, BW, feed conversion, and relative organ weight. Broilers receiving OA weighed less and had poorer feed conversions than birds not receiving OA. For broilers receiving OA, the relative weights (grams of organ weight per 100 g of BW) of the liver, proventriculus, gizzard, and heart increased, while the relative weight of the bursa decreased. Supplemental Phe decreased the relative weight of the liver and increased the relative weight of the gizzard and heart. The regression slopes for Phe at 4 mg of OA per kg of diet were significantly different from 0 for BW, the relative weights of the kidney, spleen, and pancreas and approached significance for mortality (P = .065). In the absence of supplemental Phe, 42.5% of the birds died during the study when the dose level was 4 mg of OA per kg of diet. However, when Phe was supplemented at .8 and 2.4%, only 12.5 and 15.0% of the birds died, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Impact of L-phenylalanine supplementation on the performance of three-week-old broilers fed diets containing ochratoxin A. 2. Effects on hematology and clinical chemistry.

Phenylalanine was evaluated for its ability to protect broiler chickens from the toxic effects of ochratoxin A (OA). A completely randomized 2-by-3 factorial design was utilized consisting of 0, .8, and 2.4% supplemental L-phenylalanine (Phe) and of 0 and 4 mg of OA per kg of diet. The basal diet contained 14% protein. Broilers were raised in battery brooders to 3 wk of age, when blood was collected and various hematological parameters were determined. The health status of the broilers was evaluated by assaying serum for various enzyme activities and metabolites using an automated, clinical chemistry analyzer. Adding OA to the broiler diets resulted in an increased concentration of serum hemoglobin as well as increased activity for cholinesterase and gamma glutamyl transferase but in decreased activity for aspartate amino transferase, lactate dehydrogenase, and alkaline-phosphatase activity as well as decreased concentrations of total triglyceride and of inorganic phosphorus. Supplemental Phe decreased the concentrations of hemoglobin and serum glucose. The regression slopes for Phe at 4 mg of OA per kg of diet were significant for uric acid, creatinine, total protein, albumin, and cholesterol suggesting that supplemental Phe improved the health status of the broilers fed diets containing OA with respect to these parameters.

Alkaline Phosphatase↗
PubMed1990

Diminution of aflatoxicosis in growing chickens by the dietary addition of a hydrated, sodium calcium aluminosilicate.

The amelioration of aflatoxicosis in broiler and Leghorn chickens was examined by feeding a hydrated, sodium calcium aluminosilicate (HSCAS) or activated charcoal. In three experiments, HSCAS or activated charcoal at a concentration of .5% of the total diet were incorporated into diets for broiler and Leghorn chicks containing either no added, purified aflatoxin B1 (AFB1), 7.5 mg of AFB1 per kg, or 5 mg of aflatoxin (AF) per kg (produced by Aspergillus parasiticus on rice). Compared to the controls, the AFB1 reduced BW gains at 0 to 3 wk by 21 to 38% in broilers; and the AF reduced BW gains at 0 to 4 wk in Leghorns by 20 percent. The HSCAS significantly diminished the growth-inhibitory effects of AFB1 or of AF on growing chicks by 50 to 67 percent. Feeding 5 mg of AF per kg of diet with or without charcoal to Leghorn chicks caused a significant increase in the relative weights of the liver, kidney, proventriculus, and gizzard as well as significant increases in activity of serum gamma glutamyltransferase; also, significant decreases in the relative bursa weights as well as the concentrations of serum total protein and albumin. With the exception of the relative bursa weights, the toxic effects caused by aflatoxin were prevented or were reduced by adding hydrated, sodium calcium aluminosilicate. These data suggest that HSCAS can modulate the toxicity of AFB1 and AF in the chicken; however, adding activated charcoal to the diet did not appear to have protective properties against the effects of aflatoxin B1 or of aflatoxin.

Aflatoxin B1↗
PubMed1990

Ascites in growing broilers: a research model.

A method was developed to experimentally produce ascites in broiler chickens. High-altitude simulation (treatment group) was conducted to study the development of ascites in broiler chickens. In each of three experiments, 15 male broiler chicks (1 wk old) were placed in a hypobaric chamber (principal groups) for 5 wk and 15 other chicks were reared in batteries (control groups). Ascites occurred among chicks in the principal groups recorded at 13, 27, and 80% at simulated altitudes of 1,980, 2,438, and 2,896 m, respectively. No ascites were observed in the controls at 100 m (the altitude at College Station, Texas). Body weight was significantly (P less than .05) reduced for broilers in the principal groups versus the controls-especially at 2,896 m, where the principals weighed 500 g less than the controls. The counts for hematocrit, hemoglobin, and red blood cells were significantly (P less than .05) increased in all treatment groups; while at 2,438 and 2,896 m, corticosterone was significantly reduced. Histopathology indicated consistent, mild, cardiopulmonary lesions similar to those observed in the spontaneous ascites of broiler chickens. The high-altitude simulation model will be useful in studying the etiological factors and interactions causing ascites.

Altitude↗
PubMed1990

Single and combination effects of administering salinomycin and aflatoxin to broiler chicks.

A factorial design (2 by 3) was used to evaluate the interaction between aflatoxin (0, 2.5, and 5 mg per kg) and salinomycin [0, 60 g per ton (909 kg)]. There were four replicates of 10 chicks per treatment. The chicks were maintained in batteries from 0 to 3 wk of age, with feed and water available for ad libitum intake. Aflatoxin at both levels (2.5 and 5 mg per kg) with and without salinomycin decreased body weight. The efficiency of feed utilization was affected only at the 5 mg per kg level of aflatoxin. Feeding 5 mg per kg of aflatoxin alone decreased the hemoglobin level. The inclusion of salinomycin (60 g per ton) in the diet with 2.5 or 5 mg per kg of aflatoxin initiated no significant change in body weight or feed efficiency. No significant interaction was observed between aflatoxin and salinomycin on any of the parameters measured.

Aflatoxins↗