Impairment of kidney function during aflatoxicosis

Effects of three Bacillus specious on hatchability, growth performance and serum biochemistry in Japanese quails fed diet contaminated with Aflatoxin B1

 In total, 240 one-day–old Japanese quails (Coturnix Coturnix Japonica) allocated at random to 6 treatments with 4 replicates and 10 birds in each. Treatments used were: 1) Negative control (without any additives or AFB1); 2) Positive control (basal diet + 2.5 ppm AFB1; 2); 3) TA008 (positive control + 108 cfu/ml Bacillus. megaterium TA008); 4) TA049 (positive control + 108 cfu mL-1 Bacillus. subtilis TA049); 5) TA010 (positive control+ 108 cfu mL-1 Brevibacillus brevis TA010) and 6) P (positive control + 2.5 g kg-1 Polysorb® in feed). Hatchability and embryonic mortality were significantly influenced by additives and AFB1 (p < 0.05). Birds fed TA008 improved 12 % hatchability and reduced 10 % embryonic mortality in compared to positive control (p < 0.05). Weight gain and feed conversion ratio did not affected by treatments (p > 0.05). Feed intake was significantly improved in birds feeding by TA008 at 0-21 days (p < 0.05). There were significant differences on relative weights of carcass, gizzard and proventriculus among treatments (p < 0.05). Serum total protein, albumin, cholesterol, glucose, HDL, globulin and uric acid were significantly affected by treatments (p < 0.05). These results showed that the inclusion of bacillus megaterium as potential probiotic into contaminated diets could improve the adverse effects of AFB1 in Japanese quails.

Protective effects of curcumin against aflatoxicosis: A comprehensive review

Aflatoxicosis is a deleterious medical condition that results from aflatoxins (AFs) or ochratoxins (OTs). Contamination with these toxins exerts detrimental effects on the liver, kidneys, reproductive organs, and also on immunological and cardiovascular systems. Aflatoxicosis is closely associated with overproduction of reactive oxygen species (ROS) as key contributors to oxidative and nitrosative stress responses, and subsequent damages to lipids, proteins, RNA, and DNA. The main target organ for AF toxicity is the liver, where DNA adducts, degranulation of endoplasmic reticulum, increased hepatic lipid peroxide, GSH depletion, mitochondrial dysfunction, and reduction of enzymatic and non-enzymatic antioxidants are manifestations of aflatoxicosis. Curcuma longa L. (turmeric) is a medicinal plant widely utilized all over the world for culinary and phytomedical purposes. Considering the antioxidant characteristic of curcumin, the main active component of turmeric, this review is intended to critically summarize the available evidence supporting possible effectiveness of curcumin against aflatoxicosis. Curcumin can serve as a promising candidate for attenuation of the adverse consequences of aflatoxicosis, acting mainly through intrinsic antioxidant effects aroused from its structure, modulation of the immune system as reflected by interleukin-1β and transforming growth factor-β, and interfering with AF's biotransformation by cytochrome P450 isoenzymes CYP1A, CYP3A, CYP2A, CYP2B, and CYP2C.

Determination of Environmental Exposure to Microcystin and Aflatoxin as a Risk for Renal Function Based on 5493 Rural People in Southwest China

Although the nephrotoxicity of microcystin and aflatoxin has been observed in animal and clinical cases, few population data are available. We conducted a cross-sectional study in Southwest China to investigate the association of renal function indicators (RFIs, including BUN, SCr, and eGFR) with exposure to microcystin and aflatoxin in 5493 members of the general population. Microcystin-LR levels in water and aquatic products and aflatoxin B1 levels in daily foods were measured by ELISA, and individual estimated daily intake (EDI) was assessed on the basis of the measurement and questionnaire. We found that participants with abnormal RFIs had a much higher mean level of microcystin-LR EDI than those with normal RFIs and that there was a significant increasing trend for abnormal rates and odds ratios of RFIs with increasing microcystin-LR EDI quartiles (p for trend = 0.000). Compared with the lowest quartile of microcystin-LR exposure, those in the highest quartile had significantly higher risks of abnormal BUN (OR = 1.80, 95% CI = 1.34-2.42), SCr (OR = 4.58, 95% CI = 2.92-7.21), and eGFR (OR = 4.41, 95% CI = 2.55-7.63), respectively, but no higher risk was found in subjects with higher AFB1 exposure. After adjustment for confounding factors, risk associations with microcystin-LR persisted. Consequently, our results suggest that microcystin, rather than aflatoxin, might be one important risk of renal-function impairment.

Renal pathology of the fowl--a review

On the basis of published literature and some original observations a comprehensive review is presented of the current concept of renal diseases in the fowl. All aspects of this important but much neglected subject are considered including autolysis, intoxications, inflammatory and degenerative conditions, specific viral diseases, gout, congenital abnormalities and neoplasms. The aetiology and pathogenesis of some forms of avian kidney disease are well understood but there are large gaps in our knowledge on others.

Efficacy of esterified glucomannan to counteract mycotoxicosis in naturally contaminated feed on performance and serum biochemical and hematological parameters in broilers

A study was conducted to determine the efficacy of esterified glucomannan in counteracting the toxic effects of mycotoxins in naturally contaminated diet (aflatoxin 168 ppb, ochratoxin 8.4 ppb, zearalenone 54 ppb, and T-2 toxin 32 ppb) fed to commercial broilers. One-day-old broiler chicks were randomly assigned to one of the four dietary treatments with five replicates of 14 chicks each. Four dietary treatments were 1) control; 2) esterified glucomannan, an adsorbent, tested at 0.05% of diet; 3) naturally contaminated diet; and 4) esterified glucomannan (0.05%) plus naturally contaminated diet. Body weight, feed consumption, feed efficiency, hematology, and serum biochemical and enzyme activities were evaluated. Compared with the control, the naturally contaminated diet significantly decreased body weight and feed consumption and resulted in poor feed efficiency. Esterified glucomannan effectively alleviated the growth depression caused by the naturally contaminated diet. Increased relative weights of liver and gizzard were observed in chicks fed the naturally contaminated diet. Further, feeding a naturally contaminated diet was associated with significant decreases in urea nitrogen and hematocrit values along with altered gamma-glutamyl transferase activity; however, urea nitrogen concentration was improved with addition of esterified glucomannan. These findings suggest that addition of dietary esterified glucomannan is effective in counteracting the toxic effects of naturally contaminated feed with mycotoxins.

Effects of beta-carotene and canthaxanthin on aflatoxicosis in broilers

In 2 x 3 factorial experiments, 240 broiler chicks were fed diets containing 0, 0.01, and 0.02% beta-carotene or canthaxanthin with or without 5 ppm aflatoxin to determine the effects of these two carotenoids on the health and well-being of broilers subjected to aflatoxin poisoning. Neither beta-carotene nor canthaxanthin was effective at overcoming the growth-depressing effects of aflatoxin. Relative liver weights were significantly higher in broilers receiving dietary aflatoxin in the presence of beta-carotene but not canthaxanthin. beta-Carotene and canthaxanthin had no effect on antibody production against infectious bursal disease (IBD). Interestingly, secondary antibody production against IBD was enhanced by the presence of aflatoxin in the diet. Canthaxanthin significantly increased the concentrations of cholesterol, total protein, uric acid, and triglyceride, all of which were significantly depressed by aflatoxin. beta-Carotene did not effect any of the measured blood analytes. There was a significant interaction between canthaxanthin and aflatoxin with respect to creatine kinase activity. Creatine kinase activity decreased as dietary canthaxanthin increased in the presence of aflatoxin. The data suggest that beta-carotene is not effective at ameliorating aflatoxicosis in broiler chickens but that canthaxanthin may be somewhat effective with respect to certain clinical blood chemistry indicators.

N-acetyl-beta-D-glucosaminidase as a marker of renal damage in hens

Urinary N-acetyl-beta-D-glucosaminidase (NAG) is an early physiological indicator of renal damage in several mammalian species. A study was conducted to confirm occurrence of NAG in hen urine, to establish baseline urinary NAG in laying hens, and to assess the feasibility of using the enzyme as a marker of renal damage in hens. Hy-Line hens were used in a completely randomized block design in the first part of the study. Urine was collected at 4 to 6, 6 to 10, 10 to 14, and 14 to 18 h, and serum at 4, 6, 10, and 14 h postoviposition, and assayed by spectrophotometry for NAG. Kidney tissue from additional hens was assayed histochemically for NAG. Serum NAG (range: 0.11 to 0.14 mU/mg protein) was found to be several orders of magnitude lower than urine NAG (6.44 to 12.27 mU/mg protein). Urine NAG increased from 4 to 6 h through 14 to 18 h, indicating that time of collection is critical in order to utilize the enzyme as a valid marker for laying hens. A preliminary study with five hens indicated that 10 d of treatment with liquid cholecalciferol (D3) supplement (three times the recommended level) were not enough to detect renal damage on the basis of significant changes in urine (NAG, but elevated urine NAG was detected at 40 d of D3-supplementation. Overall the results indicate that NAG in urine of laying hens is a potentially useful diagnostic marker of renal damage.

Effect of raising dietary protein, amino acids and/or energy levels as an attempt to alleviate severity of the chronic aflatoxicosis by broiler chicks. 1. Performance and toxicity symptoms

In an attempt to alleviate the aflatoxicosis symptoms by broiler chicks fed on low (50 ppb) aflatoxin-contaminated diet; the dietary nutrients were elevated by 2.6% for protein, 0.54 MJ ME/kg for energy or 0.5% for each of methionine and lysine. These supplements were mixed altogether and applied as well. All the experimental diets were offered for a 6-week period followed by a 2-week period on aflatoxin--free diet without supplements as a withdrawal period. It was proved after the treatment period that the raising of energy concentration was beneficial to overcome the aflatoxin effects on the body weight, feed conversion rate, and dressing (eviscerated weight) percentage and stability of relative weights of liver and kidneys. Additionally, the supplements' mixture improved the body weight and the relative weight of the liver comparing with the chicks fed on the aflatoxin diet without additives. All of the contaminated diets, except that of the high energy, caused apparently toxic symptoms besides the internal gross pathology. The high energy diet reflected the lowest mortality rate, whereas the highest was with the amino acids supplemented one. The withdrawal period resulted in lower differences among treatments in the body weight. It improved also the dressing percentage (significantly) and to some extent the results of the post-mortem examination.

Aflatoxicosis alters avian renal function, calcium, and vitamin D metabolism

Experiments were designed to determine the effects of aflatoxicosis on avian renal function, calcium (CA), inorganic phosphorous (Pi), and vitamin D metabolism, and to determine if the effects of aflatoxin are reversible upon discontinuation of toxin administration. Three-week-old male broiler chickens (n = 12 per treatment) received aflatoxin (AF; 2 mg/kg po) or an equal volume of corn oil, the AF carrier vehicle, for 10 consecutive days. After 10 d of treatment, half of the birds from each treatment group were anesthetized and prepared for renal function analysis, which included a 2-h phosphate loading period. Ten days after discontinuation of AF treatment, the remaining birds in each treatment group were anesthetized and prepared for renal function analysis. AF decreased plasma 25-hydroxy vitamin D [25(OH)D] and 1,25-dihydroxy vitamin D [1,25(OH)2D] levels after 5 d of treatment. After 10 d of treatment, urine flow rate (V), fractional sodium excretion (FENa), and fractional potassium excretion (FEK) were lower in AF-treated birds. In addition, total plasma Ca tended to be lower (p = .10) and fractional Ca excretion (FECa) tended to be higher (p = .10) in the AF-treated birds. Intravenous phosphate loading produced a sharp increase in urine hydrogen ion concentration ([H+]) in the AF-treated birds. Glomerular filtration rate (GFR) was reduced and plasma osmolality was increased in AF-treated birds 10 d after discontinuation of toxin administration. The results indicate that AF directly or indirectly affects Ca and Pi metabolism in avians. At the present time, the effects may be related to altered vitamin D and parathyroid hormone (PTH) metabolism. Aflatoxicosis may decrease endogenous PTH synthesis and the renal sensitivity to PTH. The AF-related increase in urine [H+] during phosphate loading is probably due to increased Na+/H+ counterport, suggesting that AF stimulates sodium reabsorption. Also, the decrease in GFR exhibited 10 d after toxin removal indicates that AF may cause prolonged alteration in renal function.

Altered renal function in broilers during aflatoxicosis

Experiments were conducted to determine the effects of aflatoxicosis on acid-base balance, urine flow rate (V), glomerular filtration rate (GFR), clearance of para-aminohippuric acid (CPAH), plasma osmolality, and the renal handling of Na, K, Ca, and P. Three-week-old broilers were gavaged with aflatoxin at a dose of 2 mg/kg of BW per day for 10 consecutive days. Control birds received an equal volume of corn oil, the aflatoxin carrier vehicle. On the eleventh day, the birds were anesthetized and prepared for renal function analysis. A solution containing inulin, para-aminohippuric acid, and mannitol was infused at a low infusion rate (.1 mL/kg of BW per min) and a high infusion rate (.4 mL/kg of BW per min) to determine if aflatoxin affects the renal response to an acute volume load. Aflatoxicosis decreased the fractional excretion of phosphorous (FEP) and plasma Ca concentration but did not significantly alter any other renal function or acid-base variables. The decrease in FEP and plasma Ca may be a direct result of renal tubular damage, decreased Ca absorption from the gut, or a result of altered circulating levels of parathyroid hormone (PTH), and possibly decreased renal sensitivity to PTH.

Distal nephron function of the rat during acute aflatoxicosis

The effect of an acute intoxication with aflatoxin B1 (AFB1) on some parameters of distal nephron function was examined in rats 48 h after a single i.p. dose of 100 micrograms/kg body wt. The parameters tested were the capacity for the excretion of fixed acids and ammonium salts during metabolic acidosis and the concentration and dilution of urine applying conventional clearance techniques. The treated rats showed a glomerular filtration rate (GFR) approx. 50% lower than the controls, but they were able to reduce the urinary pH as were nonintoxicated animals. The ammonium excretion rate per ml of GFR was unimpaired in the treated rats, but the rate of excretion of fixed acids per ml of GFR was increased. The maximal urinary osmolality was significantly diminished in the intoxicated rats as was water reabsorption, when compared with data obtained in the controls. No differences between groups were seen in the free water formation although urinary excretion of electrolytes was significantly increased. The studies support the nephrotoxicity of AFB1 in the rat probably by interfering with transport function in the collecting tubule cells together with a diffuse impairment of proximal tubule function, as observed previously.

Evaluation of immunity of young broiler chickens during simultaneous aflatoxicosis and ochratoxicosis

A 2 X 2 factorial experimental design consisting of the treatments 0 and 2.5 micrograms/g aflatoxin and 0 and 2.0 micrograms/g ochratoxin A with 12 replicates of 10 birds per treatment level was used to evaluate the effects of these mycotoxins on various aspects of immunity. Male chicks (Hubbard X Hubbard) were maintained on these treatments from one day of age to 3 weeks of age at which time six replicate pens per treatment were sacrificed and various parameters measured. The additional six replicate pens per treatment were maintained on toxin feed beyond 3 weeks of age, and at 4 weeks of age, three replicate pens were immunized with sheep red blood cells (SRBC) and Brucella abortus. Antibody titers were measured up to 10 days postimmunization. Aflatoxin and ochratoxin A, individually, significantly (P less than .05) decreased body weight, and a synergistic toxicity was evident by a significant (P less than .05) decrease in body weight. Antibody titers and phagocytic activity of heterophils were not significantly (P less than .05) altered by any treatments. The relative weight of the bursa of Fabricius and the number of follicles for a given area of the folds of the bursa of Fabricius were significantly (P less than .05) decreased only by the interaction treatment. Complement activity was significantly (P less than .05) decreased by aflatoxin and the combination of aflatoxin and ochratoxin A and depressed, although not significantly (P less than .05), by ochratoxin A.(ABSTRACT TRUNCATED AT 250 WORDS)

Alterations in renal function induced by aflatoxin B1 in the rat

The effects of aflatoxin B1 (AFB1) on renal function were determined in adult male Wistar rats by in vivo and in vitro studies. In vivo studies demonstrated that AFB1 decreased glomerular filtration rate, tubular reabsorption of glucose, and tubular transport for p-amino-hippurate. Furthermore, AFB1 pretreatment increased urinary excretion of sodium and potassium and urinary gamma-glutamyl transferase content. In vitro studies showed that slices of renal cortical tissue obtained from AFB1-treated rats (100 microgram/kg) exhibited a diminished capacity to accumulate p-aminohippurate. On the other hand, total water content of tissue, amount of extracellular water, and intracellular sodium were increased. Intracellular potassium was diminished by treatment with AFB1. Although the molecular species responsible for the effects is not known, these results indicated that AFB1 is nephrotoxic in the rat following a single low dose (100 microgram/kg body wt, ip).

Increased severity and new symptoms of infectious bursal disease during aflatoxicosis in broiler chickens

A factorial design for the presence and absence of infection with a mild strain of infectious bursal disease (IBD) virus and graded levels of dietary aflatoxin (0, .625, 1.25, 2.5, 5.0, and 10.0 microgram/g of diet) in young broiler chickens revealed several interactions which greatly changed and character of the IBD infection. An infection that was essentially free of mortality became lethal to about half the birds. A coagulopathy as indicated by prolonged prothrombin times and by the occurrence of slight hemorrhages in skeletal muscles, a hypoproteinemia, a hypocalcemia, and a markedly enlarged kidney were observed in combined aflatoxicosis and IBD, but not in IBD alone. The size of the bursa of Fabricius following an initial hypertrophy was atrophied 4 days after inoculation and the spleen was enlarged. The effects of aflatoxin and IBD on these two glands were additive. Packed blood cell volume and hemoglobin values were decreased by aflatoxin only. Thus, aflatoxin had the effects of making IBD a much more severe disease and of changing the symptoms.

Experimental aflatoxicosis in young Japanese quail

Japanese quail from the university colony fed graded levels of dietary aflatoxin (0, 1.25, 2.5, 5.0, 10.0, and 20.0 micrograms/g) from hatching to 4 weeks of age were comparatively resistant to aflatoxin as growth inhibition occurred at a dose of 5.0 micrograms/g or more as about 50% mortality occurred at a dose of 20 micrograms/g. The acute oral LD50 was 19.5 +/- 4.8 mg/kg. These values are up to ten times those reported in the literature for other quail. The most sensitive indicators of aflatoxicosis were depressed serum proteins and serum carotenoids and enlarged liver and pancreas, all of which occurred at 1.25 micrograms/g, the smallest dose administered. Unlike chickens, the serum lipids, liver lipids, hemoglobin, serum uric acid, and spleen size of quail were not affected significantly (P less than .05). The sizes of the proventriculus and gizzard were increased by doses of 5.0 micrograms/g or higher, whereas the bursa of Fabricius was regressed by the same dose.

Distribution of [14C]-labelled aflatoxin B1 in mice

The distribution of [14C]-labelled aflatoxin B1 has been studied in mice with the aid of whole-body autoradiography. In addition to the localisation of labelled aflatoxin B1 and/or its metabolities in the liver, bile, kidney, lung and urine an uptake of 14C in the pigment of the Harderian gland and the eye was observed. Uptake of radioactivity was also found in the eyes of the foetuses although their livers did not accumulate radioactivity.

Electroretinograms from broilers fed aflatoxin and T-2 toxin

Thirty chicks were fed a commercial broiler grower ration from hatching to 26 days of age. Ten birds received aflatoxin (5 microgram/g. of ration) and 10 received T-2 toxin (5 microgram/g. of ration). The remaining 10 birds served as controls. After the 26 days, electroretinograms were recorded on a graphic recorder from the anesthetized birds. On the basis of wave amplitudes and durations from electroretinograms recorded in light and darkness and from different colored stimuli, no differences were detectable between treated birds and controls. Thus, the photochemistries of the retina were not sufficiently altered in this study to permit early detection of mycotoxicoses by electroretinograms.

Effect of citrinin, a mycotoxin produced by Penicillium citrinum, on laying hens and young broiler chicks

Citrinin fed to mature laying hens at levels of 0, 50, and 250 mug/g. of diet for three weeks had no effect on body weight, feed consumption, egg production, egg weight or egg shell quality. A moderate diarrhea occurring about three days after feeding 250 mug. citrinin/g. of diet was observed. However, the diarrhea subsided once the birds were returned to a normal diet. Young broiler chicks were fed a diet containing either 0, 62.5, 125, 250, or 500 mug. citrinin/g. of diet from hatching to three weeks of age. Body weight was decreased by the 500 mug/g. level whereas all levels of citrinin resulted in enlarged kidneys and an improvement in feed conversion when compared to control values. There was also a slight dose-related increase in liver size. The 250 and 500 mug./g. levels resulted in a dose-related increase in water consumption accompanied by an acute diarrhea. Dietary citrinin had no effect on serum protein, glucose, cholesterol, uric acid, calcium, potassium and sodium concentrations or packed cell volume.

Energy and nitrogen metabolism of diseased chickens: aflatoxicosis

1. New Hampshire chicks were fed on diets containing 0 (control), 0-7 (A), or 1-1 (B) ppm of aflatoxin B1. In two trials 1-d-old chicks were offered ad libitum the three diets for 14 d. The gaseous exchange of five chickens from each group was measured for 3 or 4 d, the same diets being fed, at 2, 3, 4 and 5 weeks of age in two series of experiments. The controls were fed at the lower intake of the two other groups. Following each series of experiments at the various ages, birds were starved for 24 h and their heat production was re-measured over the next 24 h. 2. Mortality was highest and growth and food conversion poorest where the diet with the highest aflatoxin concentration was fed. Mortality was confined to the first 2 weeks. 3. Performance of birds in the chambers was improved in the second series due to differences in food intake. It also improved with age suggesting some resistance to the toxin. 4. Mean respiratory quotient was 0-97 for fed chickens on diet B. This was significantly different from 0-92 for the two other groups. Similarly, during starvation the RQ was 0-76 compared with 0-73. 5. birds fed on diet B generally grew better, retained more nitrogen and had a better energy balance in the respiration chambers than the other two groups. Metabolisability of dietary energy was less (68.5%) for all groups at 2 to 3 weeks than when older (70%) but availability of ME was the same (71%) for all groups. 6. Heat production (kJ/kg0-75) of starved birds on diet B was significantly lower than the other two groups, while endogenous nitrogen excretion was higher. 7. Water consumption (ml/g food and g/100 g body weight) was greatest for birds on diet B. 8. Although aflatoxin in the diet substantially reduced intake there was no indication that at these reduced levels of intake, nitrogen or energy metabolism were measurably impaired.