Accidental fatal aflatoxicosis due to contaminated commercial diet in 50 dogs

Cellular and molecular mechanisms of aflatoxin B1-mediated neurotoxicity: The therapeutic role of natural bioactive compounds

Aflatoxin B1 (AFB1), a dietary toxin from the mold Aspergillus species, is well acknowledged to elicit extra-hepatic toxicity in both animals and humans. The neurotoxicity of AFB1 has become a global public health concern. Contemporary research on how AFB1 enters the brain to elicit neuronal dysregulation leading to noxious neurological outcomes has increased greatly in recent years. The current review discusses several neurotoxic outcomes and susceptible targets of AFB1 toxicity at cellular, molecular and genetic levels. Specifically, neurotoxicity studies involving the use of brain homogenates, neuroblastoma cell line IMR-32, human brain microvascular endothelial cells, microglial cells, and astrocytes, as well as mammalian and non-mammalian models to unravel the mechanisms associated with AFB1 exposure are highlighted. Further, some naturally occurring bioactive compounds with compelling therapeutic effects on AFB1-induced neurotoxicity are reviewed. In conclusion, available data from literature highlight AFB1 as a neurotoxin and its possible pathological contribution to neurological disorders. Further mechanistic studies aimed at discovering and developing effective therapeutics for AFB1 neurotoxicity is warranted.

Natural mycotoxin contamination in dog food: A review on toxicity and detoxification methods

Nowadays, the companion animals (dogs or other pets) are considered as members of the family and have established strong emotional relationships with their owners. Dogs are long lived compared to food animals, so safety, adequacy, and efficacy of dog food is of great importance for their health. Cereals, cereal by-products as well as feedstuffs of plant origin are commonly employed food resources in dry food, yet are potential ingredients for mycotoxins contamination, so dogs are theoretically more vulnerable to exposure when consumed daily. Aflatoxins (AF), deoxynivalenol (DON), fumonisins (FUM), ochratoxin A (OTA), and zearalenone (ZEA) are the most frequent mycotoxins that might present in dog food and cause toxicity on the growth and metabolism of dogs. An understanding of toxicological effects and detoxification methods (physical, chemical, or biological approaches) of mycotoxins will help to improve commercial ped food quality, reduce harm and minimize exposure to dogs. Herein, we outline a description of mycotoxins detected in dog food, toxicity and clinical findings in dogs, as well as methods applied in mycotoxins detoxification. This review aims to provide a reference for future studies involved in the evaluation of the risk, preventative strategies, and clear criteria of mycotoxins for minimizing exposure, reducing harm, and preventing mycotoxicosis in dog.

HPLC–MS/MS method for the simultaneous determination of aflatoxins in blood: toxicokinetics of aflatoxin B1 and aflatoxin M1 in rats

Mycotoxins are highly toxic fungal metabolites that can pose health threats to humans and animals. Aflatoxins are a type of mycotoxin produced mainly by Aspergillus flavus and A. parasiticus. A sensitive high performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) method with multiple reaction monitoring (MRM) modes was developed for the determination of aflatoxins in blood after acetonitrile precipitation extraction. The limits of quantification of aflatoxins ranged from 0.05 to 0.2 ng/mL. Intra-day accuracy ranged from 92 to 111.0%, and intra-day precision (n = 6) ranged from 1 to 8%. Inter-day accuracy and precision were 94.0–102.0% and 2.0–8.0%, respectively. The toxicokinetics of AFB1 and its metabolite AFM1 after a single oral administration (AFB1 1 mg/kg body weight) were studied in male Sprague–Dawley rats. The blood AFB1 and AFM1 profiles could be adequately described by a noncompartmental model. The highest concentration of AFB1 (Cmax 93.42 ± 23.01 ng/mL) was observed with Tmax at 0.15 ± 0.034 h. AFB1 was rapidly metabolized to AFM1 which reached its peak blood concentration (Cmax 53.86 ± 12.12 ng/mL) at 0.33 ± 0.11 h. The HPLC–MS/MS method was simple and sensitive, appropriate for studying the in vivo toxicokinetics of aflatoxins.

The mediating role of coagulation function on the association of prenatal exposure to aflatoxin B1 and postpartum hemorrhage in Guangxi, China

Pregnant women are vulnerable to certain environmental agents, one of which is aflatoxin. As one of the most popular aflatoxins, Aflatoxin B1 (AFB1) has recently garnered increased attention concerning its potential association between exposure and adverse pregnancy outcomes. The aims of the study were to examine the associations between prenatal exposure to AFB1 and postpartum hemorrhage (PPH), and whether coagulation function has a mediating effect on their relationship. A total of 379 mother-infant pairs were included in the present study. Prenatal serum AFB1 albumin (AFB1-Alb) adduct levels in peripheral venous blood were detected by using an ELISA kit. Multiple linear and logistics regression models were applied to analyze the relationship between AFB1-Alb levels and PPH. We found mothers with high levels of AFB1-Alb adduct levels had significantly increased postpartum blood loss (partial regression coefficient (β) = 50.71, 95% confidence interval (CI) 3.48, 97.95). Mothers with high levels of AFB1-Alb adduct levels also had significantly increased risk of PPH (odds ratio (OR) = 4.81, 95% CI 1.01, 22.98). Moreover, concentrations of AFB1-Alb were positively associated with activated partial thromboplastin time (APTT) while negatively associated with fibrinogen (FIB). One-unit increase in APTT was correlated with a 6.62-ml (95% CI 3.04, 10.20) increase in postpartum blood loss. Mediation analysis suggested that the maternal blood APTT levels had a positive mediating effect in the association between AFB1-Alb adduct levels and postpartum blood loss (β = 0.32, 95% CI 0.04, 0.68). These results indicated that prenatal exposure to AFB1 was associated with increased postpartum blood loss, possibly by interfering with maternal APTT levels.

Toxic Effect of Aflatoxins in Dogs Fed Contaminated Commercial Dry Feed: A Review

Since its first patent (1897), commercial dry feed (CDF) for dogs has diversified its formulation to meet the nutritional needs of different breeds, age, or special conditions and establish a foundation for integration of these pets into urban lifestyles. The risk of aflatoxicosis in dogs has increased because the ingredients used to formulate CDF have also proliferated, making it difficult to ensure the quality required of each to achieve the safety of the entire CDF. This review contains a description of the fungi and aflatoxins detected in CDF and the ingredients commonly used for their formulation. The mechanisms of action and pathogenic effects of aflatoxins are outlined; as well as the clinical findings, and macroscopic and microscopic lesions found in aflatoxicosis in dogs. In addition, alternatives for diagnosis, treatment, and control of aflatoxins (AF) in CDF are analyzed, such as biomarkers of effect, improvement of blood coagulation, rate of elimination of AF, control of secondary infection, protection of gastric mucosa, reduction of oxidative stress, use of chemo-protectors, sequestrants, grain-free CDF, biocontrol, and maximum permitted limits, are also included.

Risk assessment of the exposure to mycotoxins in dogs and cats through the consumption of commercial dry food

Dry feed for dogs and cats sold in Europe are mostly formulated with cereals and cereal by-products, so the contamination of this food with mycotoxins represents a potential risk for these pets. We analyzed a representation of the best-selling feed brands in Spain. The presence of Aflatoxins (B₁, B₂, G₁, and G₂), Ochratoxin A, T-2 and HT-2 toxins, Deoxynivalenol, Zearalenone, and Fumonisins (B₁ and B₂) was quantified, using immunoaffinity columns and LC-MS/MS. In general, mycotoxins were frequently and simultaneously (6-11) detected, with AFB₁, FB₁, FB₂, Deoxynivalenol, and HT-2 detected in 100% of the samples. However, the concentrations of most of them are among the lowest reported so far. Fumonisins were the exception since we report the highest concentrations to date, particularly in cat feed. We practically found no significant differences in the level of mycotoxin contamination in relation to the presumed quality of the feed. We also calculated the daily exposure, and evaluated the acute and chronic health risk posed by these feeds. None of the brands analyzed presented acute risk for any of the mycotoxins. However, the high levels of fumonisins found in some samples could become problematic, if there are hidden forms of them. This is also evident in relation to long-term risk, since in the case of fumonisins the level of exposure exceeds the tolerable daily intake level in 3.5 and 12 times, for dogs and cats respectively. The exposure levels to zearalenone and deoxynivalenol could also be of long-term concern, especially considering the possibility that the continuous exposure to several mycotoxins simultaneously might produce potentiated toxic effects as a result of their synergistic action. Further research on the potential adverse health effects deriving from chronic exposure to low doses of multi-mycotoxin mixtures in pets is needed.

Recent trends in common chemical feed and food contaminants in Israel

In February 2014 a new law was approved by the Israeli parliament, namely the Control of Animal Feed Law. The law intends to regulate the production and marketing of animal feed. In preparation for the law's implementation in 2017, we have assessed the current feed and food safety challenges in Israel in recent years in association with the presence of common undesirable contaminants in various common feed and food commodities. Tight collaboration between regulatory authorities and feed/food industry, enhanced feed and food quality monitoring, transparency of survey results and readily accessible and reliable information for the public about health hazards of chemical contaminants, will guarantee the safety and quality of food and feed.

The new Israeli feed safety law: challenges in relation to animal and public health

The Israeli feed safety legislation, which came to prominence in the early 1970s, has undergone a major change from simple feed safety and quality regulations to a more holistic concept of control of feed safety and quality throughout the whole feed production chain, from farm to the end user table. In February 2014, a new law was approved by the Israeli parliament, namely the Control of Animal Feed Law, which is expected to enter into effect in 2017. The law is intended to regulate the production and marketing of animal feed, guaranteeing the safety and quality of animal products throughout the production chain. The responsibility on the implementation of the new feed law was moved from the Plant Protection Inspection Service to the Veterinary Services and Animal Health. In preparation for the law's implementation, we have characterized the various sources and production lines of feed for farm and domestic animals in Israel and assessed the current feed safety challenges in terms of potential hazards or undesirable substances. Moreover, the basic requirements for feed safety laboratories, which are mandatory for analyzing and testing for potential contaminants, are summarized for each of the contaminants discussed. © 2016 Society of Chemical Industry.

Exposure assessment of dogs to mycotoxins through consumption of dry feed

BACKGROUND

The Brazilian exportation of pet food has shown high growth rates in the last two years and determination of the exposure degree is one of the most important parameters for the risk assessment of chemical compounds. In this study the exposure degree of dogs to mycotoxins was estimated and acceptable daily intake (ADI) and safe pet dietary level (SPDL) were calculated. Thus the natural occurrence of fumonisins, zearalenone and aflatoxins was evaluated in 100 dry dog feed samples provided by pet owners in Paraná State, Brazil.

RESULTS

Despite the high frequency of fumonisins (68%), zearalenone (95%) and aflatoxins (68%) in feed samples, the mean levels detected were low. ADI for fumonisins and zearalenone was 20.0 and 1.00 µg kg(-1) body weight (BW) day(-1) respectively and SPDL for fumonisins was 2000 µg kg(-1) feed. The probable daily intake values (1.83 µg fumonisins, 0.93 µg zearalenone and 0.02 µg aflatoxins kg(-1) BW day(-1) ) were low.

CONCLUSION

The exposure degree of dogs could be assumed to be very low. However, the co-occurrence of these three or other mycotoxins, and possible synergic or additive effects, should be taken into account when determining the maximum allowed levels or risk assessment. © 2016 Society of Chemical Industry.

Impact of aflatoxin B1 on hypothalamic neuropeptides regulating feeding behavior

The presence of mycotoxins in food is a major problem of public health as they produce immunosuppressive, hepatotoxic and neurotoxic effects. Mycotoxins also induce mutagenic and carcinogenic effects after long exposure. Among mycotoxins that contaminate food are aflatoxins (AF) such as AFB1, which is the most powerful natural carcinogen. The AF poisoning results in symptoms of depression, anorexia, diarrhea, jaundice or anemia that can lead to death, but very few studies have explored the impact of AF on neuroendocrine regulations. To better understand the neurotoxic effects of AF related to anorexia, we explored in rat the impact of AFB1 on the major hypothalamic neuropeptides regulating feeding behavior, either orexigenic (NPY, Orexin, AgRP, MCH) or anorexigenic (α-MSH, CART, TRH). We also studied the effect of AFB1 on a novel neuropeptide, the secretogranin II (SgII)-derived peptide EM66, which has recently been linked to the control of food intake. For this, adult male rats were orally treated twice a week for 5 weeks with a low dose (150 μg/kg) or a high dose (300 μg/kg) of AFB1 dissolved in corn oil. Repeated exposure to AFB1 resulted in reduced body weight gain, which was highly significant for the high dose of AF. Immunocytochemical and quantitative PCR experiments revealed a dose-related decrease in the expression of all the hypothalamic neuropeptides studied in response to AFB1. Such orexigenic and anorexigenic alterations may underlie appetite disorders as they are correlated to a dose-dependent decrease in body weight gain of treated rats as compared to controls. We also found a decrease in the number of EM66-containing neurons in the arcuate nucleus of AFB1-treated animals, which was associated with a lower expression of its precursor SgII. These findings show for the first time that repeated consumption of AFB1 disrupts the hypothalamic regulation of neuropeptides involved in feeding behavior, which may contribute to the lower body weight gain associated to AF exposure.

Aflatoxicose em cães na região Sul do Rio Grande do Sul

Descrevem-se os aspectos clinicopatológicos de casos de aflatoxicose em cães no Sul do Rio Grande do Sul. Foi realizado um estudo retrospectivo dos casos diagnosticados como aflatoxicose em cães necropsiados no Laboratório Regional de Diagnóstico (LRD) da Faculdade de Veterinária da Universidade Federal de Pelotas (UFPel) no período de 1978 a 2012. Em quatro casos o diagnóstico foi confirmado pela detecção de níveis de 89 a 191 ppb de aflatoxinas B1 e G1 no alimento dos cães. De um total de 27 cães com cirrose hepática, em seis havia suspeita de aflatoxicose pelas lesões macro e microscópicas e pelo tipo de alimentação que os cães recebiam. Os sinais clínicos nos casos confirmados e nos suspeitos caracterizaram-se por apatia, diarreia, icterícia e ascite, com evolução para morte em 8 a 30 dias nos casos confirmados e em 15 a 60 dias nos casos suspeitos. A dieta era à base de derivados de milho ou arroz, farelo de amendoim e, em um caso suspeito, a dieta era ração comercial. As alterações macroscópicas caracterizaram-se por ascite, icterícia, fígado aumentado de tamanho, com ou sem nódulos, hemorragia nas serosas, conteúdo intestinal hemorrágico. Os casos foram classificados de acordo com o padrão histológico principal, caracterizado por vacuolização difusa no citoplasma de hepatócitos nos casos agudos, por proliferação de ductos biliares e discreta fibroplasia nos casos subagudos e por fibrose acentuada nos casos crônicos. Aparentemente, a enfermidade não é importante como causa de morte em cães na região, no entanto, alerta-se para a possibilidade de casos com diagnóstico de cirrose hepática sem causa determinada serem causados por aflatoxicose.