Ochratoxin A and dietary protein. 1. Effects on body weight, feed conversion, relative organ weight, and mortality in three-week-old broilers

Evaluation of prophylactic efficacy of cinnamaldehyde in murine model against Paradendryphiella arenariae mycotoxin tenuazonic acid-induced oxidative stress and organ toxicity

Cinnamaldehyde (Cin) is a natural product obtained from cinnamon and is reported to have a potential anti-fungal, anti-oxidant, anti-inflammatory and anticancer effect. The present study investigated the possible protective role of Cin against tenuazonic acid-induced mycotoxicity in the murine model. Tenuazonic acid (TeA), a toxin produced by Alternaria is a common contaminant in tomato and tomato-based products. Here, Swiss male mice were administered with TeA isolated from Paradendryphiella arenariae (MW504999) (source-tomato) through injection (238 µg/kg BW) and ingestion (475 µg/kg BW) routes for 2 weeks. Thereafter, the prophylaxis groups were treated with Cin (210 mg/kg BW). The experiment was carried out for 8 weeks. The treated groups were compared to the oral and intra-peritoneal experimental groups that received the toxin solely for 8 weeks. Haematological, histopathological and biochemical aspects of the experimental and the control mice were analysed. Sub-chronic intoxication of mice with TeA showed elevated malondialdehyde (MDA), reduced catalase (CAT) and superoxide dismutase (SOD) production; abnormal levels of aspartate transaminase (AST) and alanine transaminase (ALT). Treatment with Cin reversed TeA-induced alterations of antioxidant defense enzyme activities and significantly prevented TeA-induced organ damage. Thus, cinnamaldehyde showed therapeutic effects and toxicity reduction in TeA induced mycotoxicosis.

Effects of a modified clinoptilolite zeolite on growth performance, health status and detoxification of aflatoxin B1 and ochratoxin A in male broiler chickens

1. The aim of the present study was to test the ability of an in-feed modified clinoptilolite zeolite-based mycotoxin binding substance (Minazel® Plus, Patent Co, Misicevo, Serbia; MP) to prevent gastrointestinal absorption of aflatoxin B₁ (AFB1) and ochratoxin A (OTA) and its effects on health status and performance parameters of broilers.2. A total of 375, 1 d old male broiler chickens (Cobb 500) were used for a total trial period of 42 d (from hatch to 42 d of age). Animals were randomly allocated to five treatment groups (T1-T5), in 25 pens (15 male broilers per pen, five pens per treatment). T1 was the control maize-based diet without the addition of mycotoxins, or the test product. T2 and T3 groups received contaminated maize in the diet containing 0.02 mg AFB1/kg feed and 0.1 mg OTA/kg feed, whereas T4 and T5 groups received 0.05 mg AFB1/kg feed and 0.5 mg OTA/kg feed. The MP was added to T3 (1 g/kg feed), and T5 (2 g/kg feed) groups.3. Results showed that exposure to AFB1 and OTA at low or moderate levels, as used in this study, did not markedly affect growth performance, blood profile or organ weights. Improvements in feed conversion ratio (FCR) were observed in birds receiving MP, whereby FCR of T3 group was improved in comparison with T2 group, although there was no significant difference between T5 and T4 groups. However, average body weight gain (ABWG) was improved in the T5 group compared to T4, but not in the T3 versus T2 group comparison.4. For serum biochemical parameters, glutamate-dehydrogenase (GLDH) was significantly improved in T5 birds in comparison with T4. The addition of MP significantly decreased residue levels of AFB1 in liver and OTA in the spleen of the treated groups.5. The improvements in productive performance and reduction of mycotoxin residue levels in tissues demonstrated a beneficial effect of MP in cases of concurrent AFB1 and OTA ingestion by broilers.

Effects of encapsulated cinnamaldehyde and citral on the performance and cecal microbiota of broilers vaccinated or not vaccinated against coccidiosis

This study investigated the effects of encapsulated cinnamaldehyde (CIN) and citral (CIT) alone or in combination (CIN + CIT) on the growth performance and cecal microbiota of nonvaccinated broilers and broilers vaccinated against coccidiosis. Vaccinated (1,600) and nonvaccinated (1,600) 0-day-old male Cobb500 broilers were randomly allocated to 5 treatments: basal diet (control) and basal diet supplemented with bacitracin (BAC, 55 ppm), CIN (100 ppm), CIT (100 ppm), and CIN (100 ppm) + CIT (100 ppm). In general, body weight (BW) and feed conversion ratio were significantly improved in birds treated with BAC, CIN, CIT, and CIN + CIT (P < 0.05) but were all decreased in vaccinated birds compared with nonvaccinated birds (P < 0.05). Significant interactions (P < 0.05) between vaccination and treatments for average daily gain during the periods of starter (day 0–9) and BW on day 10 were noted. Broilers receiving vaccines (P < 0.01) or feed supplemented with BAC, CIN, CIT, or CIN + CIT (P < 0.01) showed reductions in mortality rate from day 0 to 28. The incidences of minor coccidiosis were higher (P < 0.05) in vaccinated birds than in nonvaccinated birds. Diet supplementation with BAC or tested encapsulated essential oils showed comparable effects on the coccidiosis incidences. Similar to BAC, CIN and its combination with CIT reduced both incidence and severity of necrotic enteritis (P < 0.05). No treatment effects were observed on the cecal microbiota at the phyla level. At the genus level, significant differences between vaccination and treatment groups were observed for 5 (Lactobacillus, Ruminococcus, Faecalibacterium, Enterococcus, and Clostridium) of 40 detected genera (P < 0.05). The genus Lactobacillus was more abundant in broilers fed with CIT, while Clostridium and Enterococcus were less abundant in broilers fed with CIN, CIT, or CIN + CIT in both the vaccinated and nonvaccinated groups. Results from this study suggested that CIN alone or in combination with CIT in feed could improve chicken growth performance to the level comparable with BAC and alter cecal microbiota composition.

Influence of supplementation of vitamin E on amelioration of ochratoxicosis in broiler chickens

In the present study, the effect of vitamin E supplementation in ochratoxin A (OTA) contaminated diet in amelioration of ochratoxicosis in broiler chickens was investigated. Day-old broiler chicks (n=240) were divided into six treatment groups (T1-control (basal diet); T2–T1 + 200 ppb OTA; T3–T1 + 100 mg vitamin E; T4–T1 + 200 mg vitamin E; T5–T2 + 100 mg vitamin E and T6–T2 + 200 mg vitamin E). Each diet was fed to 5 replicated groups of 8 birds each from 0 to 42 days of age. During overall growth period (0–6 week of age), the body weight gain (BWG) in ochratoxin contaminated diet (T2) fed group was lower than that of control. The BWG in group T5 was statistically similar to that of T2 fed diet and lower than that of control (T1). However, BWG in group T6 (200 mg vitamin E/kg) was higher than T2 and statistically similar to that of control group. Ochratoxin contamination in diet caused significant reduction in feed consumption, feed efficiency and livability percentage in broiler chickens. Addition of vitamin E (200 mg/kg) to the ochratoxin contaminated diet ameliorated the adverse effects on feed intake, FCR and livability percentage. Supplementation of vitamin E (200 mg/kg) to the ochratoxin contaminated diet also resulted in significant improvement in the relative weight of liver and bursa. It was concluded that experimentally induced ochratoxicosis with 200 ppb ochratoxin resulted in reduced production performance, enlargement of liver and regression of bursa. Addition of vitamin E (200 mg/kg) to the ochratoxin contaminated diet improved the production performance and relative weight of liver and bursa during 0–6 weeks of age of broiler chickens in experimentally induced ochratoxicosis caused by 200 ppb of dietary ochratoxin.

Prevalence and effects of mycotoxins on poultry health and performance, and recent development in mycotoxin counteracting strategies

Extensive research over the last couple of decades has made it obvious that mycotoxins are commonly prevalent in majority of feed ingredients. A worldwide mycotoxin survey in 2013 revealed 81% of around 3,000 grain and feed samples analyzed had at least 1 mycotoxin, which was higher than the 10-year average (from 2004 to 2013) of 76% in a total of 25,944 samples. The considerable increase in the number of positive samples in 2013 may be due to the improvements in detection methods and their sensitivity. The recently developed liquid chromatography coupled to (tandem) mass spectrometry allows the inclusion of a high number of analytes and is the most selective, sensitive, and accurate of all the mycotoxin analytical methods. Mycotoxins can affect the animals either individually or additively in the presence of more than 1 mycotoxin, and may affect various organs such as gastrointestinal tract, liver, and immune system, essentially resulting in reduced productivity of the birds and mortality in extreme cases. While the use of mycotoxin binding agents has been a commonly used counteracting strategy, considering the great diversity in the chemical structures of mycotoxins, it is very obvious that there is no single method that can be used to deactivate mycotoxins in feed. Therefore, different strategies have to be combined in order to specifically target individual mycotoxins without impacting the quality of feed. Enzymatic or microbial detoxification, referred to as "biotransformation" or "biodetoxification," utilizes microorganisms or purified enzymes thereof to catabolize the entire mycotoxin or transform or cleave it to less or non-toxic compounds. However, the awareness on the prevalence of mycotoxins, available modern techniques to analyze them, the effects of mycotoxicoses, and the recent developments in the ways to safely eliminate the mycotoxins from the feed are very minimal among the producers. This symposium review paper comprehensively discusses the above mentioned aspects.

Toxico-Pathological Effects of In Ovo Inoculation of Ochratoxin A (OTA) in Chick Embryos and Subsequently in Hatched Chicks

This study was designed to investigate the toxico-pathological effects of in ovo inoculation of ochratoxin A (OTA) in chicken embryos and subsequently in the hatching chicks. Nine hundred fertile white leghorn (WL) layer breeder eggs were divided into eight groups (A–H). Group A was maintained as untreated control, whereas group B was kept as sham control (10 µL of 0.1 M NaHCO3 solution). Before incubation, groups C, D, E, F, G, and H were injected with 0.01, 0.03, 0.05, 0.10, 0.50, and 1.00 µg OTA/egg, respectively. At 53 hrs of incubation, crown to rump length, optic cups, and eye lens diameters were significantly ( p ≤ .05) lower, whereas neural tube closure defects were higher in the OTA-treated embryos. Teratogenic defects (studied at day 9 of incubation) and embryonic mortalities were higher in the groups administered high doses of OTA. A significant increase was noted in the serum concentration of ALT, urea, and creatinine, along with higher weights of liver and kidney, in chicks hatched from OTA-contaminated eggs. These findings suggested that there are teratogenic and substantive toxicological risks in the developing chicken embryos and hatched chicks that could be exposed to OTA in ovo.

Effect of ochratoxin A on coccidiosis-challenged broiler chicks

A study was conducted to evaluate the effects of ochratoxin A (OTA) on broiler chicks challenged with Eimeria tenella oocysts. Two hundred day-old, unsexed Cobb broiler chicks were randomly divided into four treatment groups. Each treatment consisted of five replicates and ten chicks per replicate, making the following treatments: group I: control; group II: OTA (1 mg/kg) daily through feed; group III: coccidia (orally inoculated with 50,000 E. tenella oocysts/chick on day 21); group IV: OTA (1 mg/kg) daily through feed + coccidia (orally inoculated with 50,000 E. tenella oocysts/chick on day 21). Six birds from each group were slaughtered on the 5th, 7th, 9th and 11th day post infection. The results showed higher mortality with severe gross lesions in caecum and a greater number of faecal oocysts in groups III and IV. The gross lesions observed in group IV were characterised by distension of caecum with blood-tinged content indicative of haemorrhagic typhlitis with mucosal tissue debris. Microscopically, lymphoid organs revealed severe lymphocytolysis and depletion with cellular sparsity in OTA treated groups. The increased severity of lesions in the caecum of group IV was attributed to the additive effect of OTA and E. tenella. Caecum exhibited severe haemorrhages, the presence of numerous second generation schizonts, matured merozoites and developing oocysts. Group IV showed an increase in the severity of coccidiosis which is due to the immunosuppressive effect of OTA. Thus, it was concluded that the expression of E. tenella and its pathological effects were maximum in the presence of OTA compared to the incidence of coccidiosis alone in broiler chicks.

Effect of ochratoxin a on body weight, feed intake and feed conversion in broiler chicken

The effect of ochratoxin A (OA) on the body weight, feed intake, and feed conversion was investigated in broiler chicken fed dietary levels of OA at 0, 1, and 2 ppm for 28 days from hatch. Feeding OA significantly reduced the growth rate of broiler chicken. The reduction was observed from the first week onwards in OA-treated groups. Feed consumption and feed conversion also showed a diminishing trend from the first week of feeding toxin. Its implication on the performance of broiler chicken is discussed.

Preventive and therapeutic methods against the toxic effects of mycotoxins - a review

Ingredients used in animal feeds and their contamination with undesirable substances, such as mycotoxins, are fundamentally important both in terms of the quality of animal products and the potential human health impacts associated with the animal-based food production chain. Feed ingredients contaminated with mycotoxins may have a wide range of toxicological effects on animals. Therefore, mycotoxin contamination of feed ingredients constituting complete feed products represents an important potential hazard in farm animal production. This review summarises the potential effects of some preventive methods used during the storage of cereal grains as well as of nutritive (e.g. antioxidants, amino acids, fats) or non-nutritive compounds (e.g. pharmacological substances, carbon- or silica-based polymers) and detoxifying enzymes recommended for use against the toxic effects of different mycotoxins.

Studies on some feed additives and materials giving partial protection against the suppressive effect of ochratoxin A on egg production of laying hens

The protective effects of various feed supplements against the harmful effect of ochratoxin A on egg production and sexual maturation of two-weeks old Plymouth Rock female chicks designed for laying hens were studied. A significant protective effect of the feed additives or materials: water extract of artichoke (WEA), sesame seed (SS), Roxazyme-G (RG) and l-beta phenylalanine (PHE) against the suppressive effect of ochratoxin A (OTA) on egg production of laying hens was found. A similar protection was also seen on the toxic effect of OTA on various internal organs of the same hens. A significant protection was found against the decrease of the weight or the quantity of eggs as well as against the delay of the beginning of the laying period of chicks, both of which were provoked by ochratoxin A. These protective effects were strongest in chicks treated with SS or WEA, but were slightest in chicks treated with l-beta PHE.

Complex etiology, prophylaxis and hygiene control in mycotoxic nephropathies in farm animals and humans

Various etiological factors contributing to the development of mycotoxic nephropathy in farm animals and humans are reviewed. The possible synergistic effect between ochratoxin A (OTA) and other mycotoxins, as penicillic acid (PA) and fumonisin B(1) (FB(1)), contributing to this nephropathy is also considered and discussed. The most convenient ways of prophylaxis and various preventive measures against OTA contamination of feeds or foods are reviewed. A reference is made concerning the most successful methods of veterinary hygiene control in the slaughterhouses in order to prevent the entering of OTA in commercial channels with a view to human health. The economic efficacy of these prophylactic procedures is also considered. An evaluation of human exposure to OTA is made.

Ochratoxin A: An overview on toxicity and carcinogenicity in animals and humans

Ochratoxin A (OTA) is a ubiquitous mycotoxin produced by fungi of improperly stored food products. OTA is nephrotoxic and is suspected of being the main etiological agent responsible for human Balkan endemic nephropathy (BEN) and associated urinary tract tumours. Striking similarities between OTA-induced porcine nephropathy in pigs and BEN in humans are observed. International Agency for Research on Cancer (IARC) has classified OTA as a possible human carcinogen (group 2B). Currently, the mode of carcinogenic action by OTA is unknown. OTA is genotoxic following oxidative metabolism. This activity is thought to play a central role in OTA-mediated carcinogenesis and may be divided into direct (covalent DNA adduction) and indirect (oxidative DNA damage) mechanisms of action. Evidence for a direct mode of genotoxicity has been derived from the sensitive 32P-postlabelling assay. OTA facilitates guanine-specific DNA adducts in vitro and in rat and pig kidney orally dosed, one adduct comigrates with a synthetic carbon (C)-bonded C8-dG OTA adduct standard. In this paper, our current understanding of OTA toxicity and carcinogenicity are reviewed. The available evidence suggests that OTA is a genotoxic carcinogen by induction of oxidative DNA lesions coupled with direct DNA adducts via quinone formation. This mechanism of action should be used to establish acceptable intake levels of OTA from human food sources.

Experimental ochratoxicosis in broiler chickens

This study describes the toxicity signs that developed when the diet of male broiler chickens was artificially contaminated with different levels of the mycotoxin ochratoxin A (OTA). Chicks were assigned randomly to three groups of 80 chicks that were fed a diet containing 0 parts per billion (ppb) (control, group 1), 400 ppb (group 2) or 800 ppb (group 3) OTA from day 1 to 5 weeks of age. Signs of ochratoxicosis were assessed on the basis of changes in the following criteria: body weight, relative weights of two representative internal organs (gizzard and thymus), feed consumption, feed conversion ratio, mortality, thyroid activity, blood profile, humoral and cell mediated immunity. Feeding OTA at levels of 400 and 800 ppb (groups 2 and 3) significantly decreased the body weight, thymus weight, feed consumption, feed conversion ratio and thyroxine concentration (P < 0.05). The OTA groups developed anaemia manifested by a significant decrease in the red blood cell count, packed cell volume percentage and haemoglobin concentration (P < 0.05). By the end of the experiment both groups that received OTA showed a 37% reduction in red blood cell count compared with the control group. Furthermore, a significant decrease in the white blood cell count, humoral immune response and cell-mediated immunity was found in both groups fed ochratoxin compared with the control group (P < 0.05). The reduction in the above parameters was more noticeable with time and was proportional to the level of OTA exposure. A significant increase in relative gizzard weight, cumulative mortality and triiodothyronine concentration was found in OTA-fed chicks (P < 0.05). These data provide a description of ochratoxicosis in broilers that should be useful in diagnosis and in improved understanding of the practical implications on broiler performance and health, a problem that can threaten the poultry industry.

Balkan endemic nephropathy and associated urinary tract tumours: a review on aetiological causes and the potential role of mycotoxins

A series of publications in the 1950s described a kidney disease in Bulgaria, the former Yugoslavia and Romania that became known as Balkan endemic nephropathy (BEN). The disease was qualified by World Health Organisation (WHO) experts as 'progressive and very gradually developing renal failure with insidious onset.... The last stage shows marked fibrosis...'. BEN is characterized by tubular degeneration, interstitial fibrosis and hyalinization of glomeruli accompanied by enzymuria and impaired renal function without nephrotic syndrome. Later, an association between BEN and tumours of the kidney pelvis and ureter was recognized, so that the problem of BEN became not only nephrological, but also oncological. There may also be an association with increased urinary bladder cancer incidence, although many confounding factors may interfere in the analysis of data for this organ. In view of the very intimate association between BEN and the urinary tract tumours (UTT), the term 'endemic uropathy' has been proposed. Several hypothesis concerning the aetiology of these diseases has been investigated, which include: predisposing genes factors, environmental factors (heavy metals, minerals, bacteria, leptospira, viruses, fungal toxins and, most recently, pliocene lignites). This paper reviews the different hypotheses about the aetiology of endemic uropathy and pays particular attention to the role of fungal toxins.