Discovery of novel fungal species and pathogens on bat carcasses in a cave in Yunnan Province, China.

Virulent infectious fungal diseases, in natural and managed landscapes, are increasing. Fungal diseases in humans, animals and plants have caused die-off and extinction events and have become a threat to food security. A caving expedition in Yunnan Province, China, revealed two bat carcasses covered in fungal mycelia. Eleven fungal isolates were obtained from these bat carcasses, and morphological observations and multigene phylogenetic analyses revealed they were Fusarium incarnatum, Mucor hiemalis and Trichoderma harzianum and four new species, Mortierella rhinolophicola, M. multispora, M. yunnanensis and Neocosmospora pallidimors. One of the more alarming findings is that a number of infections related to Neocosmospora, previously associated with human and animal mycotoxicoses, are reported to be increasing, and here we present a new species from this genus, isolated from dead bats. Due to the ecosystem services provided by bats, and the close relationship between bats and humans, future research should focus on the impacts and significance of N. pallidimors to human and animal health, examining its pathogenicity and secondary metabolites. Taxonomic descriptions, color images of the habitat, in situ samples, microstructures and cultures are presented. SEM photographs of microstructures and phylogenetic trees showing the placement of new and known species are also provided.

Toxic tall fescue grazing increases susceptibility of the Angus steer fecal microbiota and plasma/urine metabolome to environmental effects.

Impaired thermoregulation and lowered average daily gains (ADG) result when livestock graze toxic endophyte (Epichloë coenophialum)-infected tall fescue (E+) and are hallmark signs of fescue toxicosis (FT), a disease exacerbated by increased temperature and humidity (+temperature-humidity index; +THI). We previously reported FT is associated with metabolic and microbiota perturbations under thermoneutral conditions; here, we assessed the influence of E+ grazing and +THI on the microbiota:metabolome interactions. Using high-resolution metabolomics and 16S rRNA gene sequencing, plasma/urine metabolomes and the fecal microbiota of Angus steers grazing non-toxic or E+ tall fescue were evaluated in the context of +THI. E+ grazing affected the fecal microbiota profile; +THI conditions modulated the microbiota only in E+ steers. E+ also perturbed many metabolic pathways, namely amino acid and inflammation-related metabolism; +THI affected these pathways only in E+ steers. Integrative analyses revealed the E+ microbiota correlated and co-varied with the metabolomes in a THI-dependent manner. Operational taxonomic units in the families Peptococcaceae, Clostridiaceae, and Ruminococcaceae correlated with production parameters (e.g., ADG) and with multiple plasma/urine metabolic features, providing putative FT biomarkers and/or targets for the development of FT therapeutics. Overall, this study suggests that E+ grazing increases Angus steer susceptibility to +THI, and offers possible targets for FT interventions.

Physiological response, function of sweat glands, and hair follicle cycling in cattle in response to fescue toxicosis and hair genotype.

Fescue toxicosis is a syndrome that results when cattle consume toxic endophyte-infected tall fescue. The objective of this study was to compare the response in physiological variables, sweat gland function, hair follicle cycling, and gene expression to feeding a total mixed ration that included tall fescue haylage and tall fescue seed containing a toxic endophyte (EI) or tall fescue haylage containing a nontoxic novel endophyte (EN) in beef heifers (Angus × Senepol heifers, n = 31) with 2 different hair genotypes. Numbers in each subgroup were as follows: novel endophyte, heterozygous slick (EN-S; n = 8), novel endophyte, homozygous hairy (wild type, EN-W; n = 7), endophyte-infected, heterozygous slick (EI-S; n = 10), and endophyte-infected, homozygous hairy (wild type, EI-W; n = 6). Physiological measurements were taken weekly for 7 wk. Data were analyzed using the MIXED procedure of SAS including dietary fescue treatment (EN vs. EI) and hair genotype (S vs. W) as main effects, day as a repeated measure, and temperature-humidity index (THI) as a covariate. Skin biopsies were taken before treatment initiation and on day 37 of treatment. Average surface temperature (ST) increased as the THI increased (P < 0.0001). Average ST was greater (P < 0.01) for animals fed EI than for animals fed the EN fescue diet, and greater (P < 0.01) for animals with the W genotype compared with animals with the S genotype. The difference between heifers with the S and W genotype was greater at greater THI (genotype × day interaction, P < 0.01). Transepidermal water loss (TEWL) was greater (P < 0.05) for animals with the S genotype compared with the W genotype and greater (P < 0.05) for heifers with the S genotype than for heifers with the W genotype when fed EI (36.7, 38.5, 30.0, and 38.7 g/m2 per hour for EN-W, EN-S, EI-W, and EI-S, respectively). The fraction of follicles in telogen in plucked hair samples for heifers fed EI was greater for animals with the S genotype than the W genotype (fraction in telogen: 0.456, 0.565, 0.297, 0.702 for EN-W, EN-S, EI-W, and EI-S, respectively; diet × genotype interaction, P < 0.05). Fraction of follicles in anagen was the opposite. EI fescue resulted in increased ST, changes in hair follicle cycling that support greater hair growth, and decreased TEWL for heifers with the W genotype compared with S genotype, suggesting greater heat stress in response to EI.

The influence of local market and household factors on aflatoxin presence in maize and symptoms of its exposure to children in Guatemala.

Recent evidence supports the hypothesis that aflatoxin exposure from maize can influence malnutrition rates among children. Therefore, in Guatemala we investigated two questions; which maize sources exposed households to higher risk of aflatoxin exposure symptoms and what the risk factors were for each maize source, pre- and post-maize harvest. Survey data and household maize samples were collected in October 2016 (pre-harvest) and February 2017 (post-harvest) in San Vicente, Guatemala. Structural equation modeling (SEM) and odds ratios were used to assess the data. The results suggested that households which purchased maize from the market had 3.64 higher odds of high levels of aflatoxin. The models identified that good market purchase habits were significant for market-based maize sources while improved post-harvest practices and improved types of maize storage were significant for subsistence-based maize sources. Cumulative results suggest multiple interventions may be effective but are dependent on time of year and source of maize.

Investigation of antifungal activity of surfactin against mycotoxigenic phytopathogenic fungus Fusarium moniliforme and its impact in seed germination and mycotoxicosis.

The mycotoxigenic phytopathogenic fungus such as Fusarium moniliforme contamination in maize kernels may not only affect seed germination but also negatively cause mycotoxicosis in animals and humans. There is no effective fungicides to control the growth of F. moniliforme on maize kernels. Hence, effective bioactive compounds are needed to prevent plant and animal diseases associated with F. moniliforme contamination in cereals. Surfactin is an well-known antimicrobial lipopeptide has strong antifungal activities against several phytopathogenic fungi and may have potential uses in agriculture. So, in this present study the antifungal activity of surfactin extracted from Brevibacillus brevis KN8(2) was investigated against F. moniliforme, further its impact in seed germination and mycotoxicosis was also studied. Our results showed that surfactin inhibited and damaged the hyphae of F. moniliforme in in vitro. The agarose gel electrophoresis, SDS-PAGE analysis and biochemical assay presented that surfactin damaged the DNA, protein and reduced the GSH content in F. moniliforme. Furthermore, surfactin prevent maize seed germination problem and mycotoxicosis in animal model associated with F. moniliforme via prevention of F. moniliforme contamination on maize kernels. These findings revealed that surfactin could be an effective bio-fungicide in the plant disease management.

Aflatoxin B1 and total fumonisin contamination and their producing fungi in fresh and stored sorghum grain in East Hararghe, Ethiopia.

Natural contamination of sorghum grains by aflatoxin B1 and total fumonisin and their producing toxigenic fungi has been studied. A total of 90 sorghum grain samples were collected from small-scale farmers' threshing floors and 5-6 months later from underground pits during 2013 harvest from three districts of East Hararghe, Ethiopia. Mycotoxin analysis was done using enzyme-linked immunosorbent assay (ELISA). The limits of detection were in the range 0.01-0.03 µg kg-1. The results revealed that all sorghum grain samples were contaminated with both Aspergillus and Fusarium species. Aflatoxin B1 was detected at levels ranging from

The role of bentonite binders in single or concomitant mycotoxin contamination of chicken diets.

Concomitant presence of mycotoxins is more likely to appear than a single mycotoxicosis since many mycotoxigenic fungi grow and produce their toxic metabolites under similar conditions. The present study was designed to evaluate the efficacy of 4 mycotoxin binders to protect meat-type chickens against single and concomitant administration in the feed of two mycotoxins, namely aflatoxin B1 (AFB1) and ochratoxin A (OTA) both at concentration of 0.1 mg/kg. A total of 440 as hatched, d-old, Ross 308 broilers were reared for 42 d. There were 11 dietary treatments. Chickens were fed on either an uncontaminated basal diet, basal diet and AFB1, basal with concomitant presence of AFB1 and OTA, basal diet and three binders A, B and C (1%) with or without AFB1 or basal diet and binder D (0.5%) with or without concomitant presence of AFB1 and OTA. Performance, carcass yield and several biochemical parameters were examined. Mycotoxin concentration in liver and breast muscle samples was determined. Broiler performance under concomitant mycotoxin contamination was poorer than that under single mycotoxicosis. Mycotoxin presence increased relative heart weight compared to that of broilers fed on uncontaminated diets. Only OTA and not AFB1 was detected and only in the liver. OTA concentration was four-fold lower in broilers fed on a diet with binder compared to those fed on contaminated diets without binder. In conclusion, the study revealed that binder composition and presence or not of multiple toxins may be important factors for optimum broiler performance under mycotoxicosis.

Interactive effects of dietary protein concentration and aflatoxin B1 on performance, nutrient digestibility, and gut health in broiler chicks.

A 20-day trial was conducted to determine the impact of aflatoxin B1 (AFB1) and dietary protein concentration on performance, nutrient digestibility, and gut health in broiler chicks. The 6 dietary treatments were arranged in a 2 × 3 factorial with 3 crude protein (CP) concentrations (16, 22, and 26%) with or without 1.5 mg/kg AFB1 Each diet was fed to 6 replicate cages (6 chicks per cage) from zero to 20 d of age. Endogenous N and amino acid loss were estimated from birds fed a N-free diet with or without 1.5 mg/kg AFB1 A significant interaction between AFB1 and CP concentration was observed for growth performance, where reduction of BW gain, feed intake, gain:feed ratio, and breast muscle weight by AFB1 were most profound in birds fed the 16%-CP diet, and were completely eliminated when birds were fed the 26%-CP diet (AFB1 by CP interaction; P ≤ 0.023). Similarly, AFB1 reduced serum albumin, total protein, and globulin concentrations in birds fed 16 and 22% CP diets, but not in those fed the 26%-CP (AFB1 by CP interaction; P ≤ 0.071). Gut permeability was increased in birds fed AFB1-contamiated diets as measured by serum lactulose/rhamnose ratio (main effect; P = 0.04). Additionally, AFB1 tended to increase endogenous N loss (P = 0.09), and significantly reduced apparent ileal digestible energy and standardized ileal N and amino acid digestibility in birds fed the 16%-CP diet, while birds fed higher dietary CP were not affected (AFB1 by CP interaction; P ≤ 0.01). Further, AFB1 increased the translation initiation factor 4E-binding protein (4EBP1), claudin1, and multiple jejunal amino acid transporters expression (main effect; P ≤ 0.04). Results from this study indicate that a 1.5 mg AFB1/kg diet significantly impairs growth, major serum biochemistry measures, gut barrier, endogenous loss, and energy and amino acid digestibility. Aflatoxicosis can be augmented by low dietary CP, while higher dietary CP completely eliminated the impairment of performance, serum proteins, and nutrient digestibility from aflatoxicosis in zero to 20 d broiler chicks.

Impact of dietary branched chain amino acids concentration on broiler chicks during aflatoxicosis.

A 20-day trial was conducted to determine the effects of dietary branched-chain amino acids (BCAA) on performance, nutrient digestibility, and gene expression of the mTOR pathway in broiler chicks when exposed to aflatoxin B1 (AFB1). The 6 dietary treatments were arranged in a 2 × 3 factorial with 3 BCAA concentrations (1.16, 1.94, and 2.73%) with or without 1.5 mg/kg AFB1 (1.77 mg/kg analyzed). Each diet was fed to 8 replicate cages (6 chicks per cage) from 6 to 20 d of age. Exposure to AFB1 significantly reduced gain:feed ratio and breast muscle weight (P < 0.05), and tended to decrease cumulative BW gain (P = 0.087), while increasing dietary BCAA improved all performance measures (P ≤ 0.0002), except relative breast muscle weight. Apparent ileal digestibility of N and 9 amino acids were increased by AFB1 (P ≤ 0.05), but were reduced by higher dietary BCAA (P ≤ 0.023). Jejunum histology was not affected by AFB1, while higher dietary BCAA tended to increase villus height (P = 0.08). Additionally, the gene expression of mTOR pathway (mTOR, 4EBP1, and S6K1) from liver and jejunum were not affected by dietary treatments, while muscle expression of S6K1 tended to be increased by AFB1 (P = 0.07). No significant interaction between AFB1 and dietary BCAA were observed for any measures in the current study. Results from this study suggested that feed AFB1 contamination can significantly reduce growth performance and breast muscle growth in broiler chicks at 20 d. Higher BCAA supply may have beneficial impact on bird performance, but this effect is independent of AFB1 exposure.

Effects of dietary protein concentration on performance and nutrient digestibility in Pekin ducks during aflatoxicosis.

A 14-d study was conducted to determine the impact of dietary crude protein concentration on performance, serum biochemistry, and nutrient digestive functions in Pekin ducklings during aflatoxicosis. A total of 144 male Pekin ducklings were randomly allotted to 4 dietary treatments arranged in a 2×2 factorial with 2 crude protein (CP) (20 and 24% on an analyzed basis) with or without 0.2 mg/kg aflatoxin B1 (AFB1) (0.21 mg/kg analyzed). The AFB1 reduced BW gain, feed intake, and breast muscle weight by 33 to 43% (P<0.0001). Serum concentration of protein, glucose, and Ca were also decreased by AFB1 (P≤0.0015), while pancreatic activities of amylase and lipase were increased by AFB1 (P<0.005). Apparent N digestibility was not affected by dietary treatment, whereas apparent ileal digestible energy was reduced 7.6% by AFB1 (P=0.0003). Higher dietary CP improved BW gain, gain:feed ratio, and breast muscle weight (P≤0.021), and tended to improve feed intake (P=0.094), but did not improve serum measures, digestive enzyme activity, or nutrient digestibility. No statistical interaction of AFB1 by CP was observed for any measures. Results from the current study suggest that AFB1 at low concentration can significantly impair performance of Pekin ducklings primarily through inhibited feed intake, as well as influence nutrient digestion processes (jejunum morphology, digestive enzyme activity, and apparent energy digestibility). Higher dietary CP can improve growth performance of ducklings regardless of AF exposure, but did not interact with dietary AFB1 on performance, serum biochemistry, or nutrient digestion in Pekin ducklings from hatch to 14 d.

Plant poisonings in livestock in Brazil and South Africa.

Information on intoxication of livestock by plants in Brazil, in terms of cause, clinical signs and pathology, is compared with information on livestock poisoning by plants in South Africa. Plant poisoning, including mycotoxicosis, is considered to be one of three major causes of death in livestock in Brazil, which is one of the top beef producing countries in the world, with a cattle population of more than 200 million. Cattle production in South Africa is on a more modest scale, but with some 600 species of plants and fungi known to cause toxicity in livestock, as opposed to some 130 species in Brazil, the risk to livestock in South Africa appears to be much greater. The comparisons discussed in this communication are largely restricted to ruminants.

Efficacy of adsorbents (bentonite and diatomaceous earth) and turmeric (Curcuma longa) in alleviating the toxic effects of aflatoxin in chicks.

A study was conducted to determine the efficacy of bentonite clay (BC), diatomaceous earth (DE) and turmeric powder (TUM) in alleviating the toxic effects of aflatoxin B1 (AFB1). A total of 250 Ross-308 d-old male broiler chicks were assigned to 10 dietary treatments (5 replicates of 5 chicks) from hatch to d 21. Dietary treatments were: basal diet; basal diet plus AFB1 (2 mg) or BC (0.75%), or DE (0.75%), or TUM (200 mg/kg curcuminoids) and different combinations of AFB1, BC, DE and TUM. Feed intake (FI), body weight gain (BWG) and feed gain (FG) of the birds fed on BC or DE separately were not different from control birds. Birds fed on TUM only had similar FI and FG but lower BWG than control chicks. Aflatoxin B1 reduced FI, BWG and serum concentrations of glucose, albumin, total protein calcium, but increased FG and relative liver and kidney weights. Chicks fed on the combination of AFB1 and BC had similar FI and FG to control chicks. Chicks fed on the combination of DE and AFB1 had lower FI (23.1%) and BWG (28.6%) compared with control chicks. Chicks fed on the combination of TUM and AFB1 also had decreased FI (26.2 %) and BWG (31%) compared with control chicks. Chicks fed on the combination of AFB1, BC and TUM consumed significantly higher amounts of feed compared with chicks fed on only AF, but gained less when compared with control diet chicks. Chicks fed on the combination of AFB1, DE and TUM diet had poorer growth performance than those fed on AFB1 alone. None of the combination diets reduced the severity of liver lesions.

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.

Regional differences in the fescue toxicosis response of Bos taurus cattle.

Cattle of the same breed from different regions of the USA may have altered responses to heat stress and fescue toxicosis. Angus steers from Missouri (MO ANG, n = 10, 513.6 ± 13.6 kg BW) and Oklahoma (OK ANG, n = 10, 552.8 ± 12.0 kg BW) were fed a diet containing either endophyte-infected (E+, 30 µg ergovaline/kg BW/day) or endophyte-uninfected (E-, 0 µg ergovaline/kg BW/day) tall fescue seed for 23 days. Diet treatment began on day 2. Animals were maintained at thermoneutrality (TN, 19-22 °C, days 1-8) and then exposed to heat stress (HS, cycling 26-36 °C, days 9-22). On day 23, ambient temperature was returned to TN and used as a recovery day. Feed intake (FI) was measured daily, with rectal and skin temperatures determined six times daily. Feed intake reduction from pretreatment levels was greater (P < 0.01) for E + (13.9 ± 0.9 versus 11.9 ± 0.3 kg/day) compared to E - (12.6 ± 0.9 versus 12.4 ± 0.3 kg/day) steers over the entire TN period, regardless of Angus group. During HS, E + cattle had reduced FI (P < 0.02; 6.9 ± 0.2 versus 8.4 ± 0.2 kg/day) compared to E - animals, independent of region of origin. A greater decrease in FI (P < 0.01) was observed for OK (12.1 ± 0.3 versus 6.2 ± 0.2 kg/day) compared to MO ANG (12.2 ± 0.3 versus 7.9 ± 0.2 kg/day) when ambient temperature was increased from TN to HS. On day 13 and days 15-22, OK ANG (E+) had reduced FI (P < 0.01, -2.21 kg) compared to OK ANG (E-), while there was no effect on MO ANG. From day 12 to day 22 of HS, daily minimum temperatures for ear, rump, and tail skin were less for E + (P < 0.05) when compared with E-treated steers, signifying peripheral vasoconstriction in E + animals. This was supported by reduced shoulder and lower tail temperatures (P < 0.01) for E + compared to E-treated OK ANG on the recovery day. In summary, regional differences in the response to fescue toxicosis exist, with peripheral vasomotor effects becoming most evident when animals are subjected to rapid changes in their environment.

The effect of experimental fusarium mycotoxicosis on microbiota diversity in porcine ascending colon contents.

The objective of the study was to determine the effect of exposure of pigs to the Fusarium mycotoxins zearalenone (ZEN) and deoxynivalenol (DON), administered together and separately, on the colon microbiota. An experiment was conducted for 42 days on gilts, randomly assigned to four groups and administered either ZEN, DON, ZEN+DON, or a placebo. The number of aerobic mesophilic bacteria, yeasts, molds, anaerobic Clostridium perfringens, fecal streptococci, Enterobacteriaceae, Escherichia coli, and lactic acid bacteria (LAB) were determined in the contents of the ascending colon. The influence of mycotoxins on the functional diversity of the colonic microbiota was assessed using EcoPlate tests (Biolog). Analysis revealed the predominance of LAB in all groups of pigs. Zearalenone, administered separately and together with DON, was found to have an adverse effect on mesophilic aerobic bacteria, but only after long exposure to this mycotoxin. During the six weeks of the experiment, the concentration of C. perfringens, E. coli, and other bacteria in the family Enterobacteriaceae was most considerably reduced in the experimental groups exposed to zearalenone, both separately and together with DON. Mycotoxins also affected the functional biodiversity of microorganisms. Both Shannon's diversity index and the number of catabolized substrates in Biolog plate (the R index) were much higher in the group subjected to mixed mycotoxicosis.

Towards genomic selection for facial eczema disease tolerance in the New Zealand sheep industry.

Pithomycotoxicosis, more commonly known as facial eczema (FE), is a liver disease that occurs predominantly in New Zealand because of its toxigenic Pithomyces chartarum strains. The first reported case was in sheep in 1887. Since the 1930s, a number of studies have been conducted in an attempt to mitigate the problems FE has on the sheep and dairy industries. The research in these studies included work on fungicide and biological control of the saprophytic fungus, use of different pasture plants to inhibit fungal growth, stock management with respect to pasture fungal spore counts and the use of zinc prophylaxis on animals. The finding that there was a genetic basis in FE sensitivity in sheep prompted research for a genetic approach to mitigation in the form of a diagnostic DNA test for susceptibility to the disease. Recently, we have used the Illumina OvineSNP50 BeadChip to develop a genome-enabled prediction approach to screen for FE-tolerant sheep. Our current best genomic prediction for FE is for the Romney breed and has an accuracy of 0.38. This prediction accuracy is not as high as the individual accuracy gained by an artificial challenge test (0.64). However, it has the advantage of being a non-invasive test and can be provided as part of genomic testing for other traits at minimal cost.

Mycotoxicoses of ruminants and horses.

In the current study, mycotoxicoses of ruminants and horses are reviewed, with an emphasis on the occurrence of these diseases in South America. The main mycotoxicoses observed in grazing cattle include intoxications by indole-diterpenoid mycotoxins (Paspalum spp. contaminated by Claviceps paspali, Lolium perenne infected by Neotyphodium lolii, Cynodon dactylon infected by Claviceps cynodontis, and Poa huecu), gangrenous ergotism and dysthermic syndrome (hyperthermia) caused by Festuca arundinacea (syn. Festuca elatior) infected by Neotyphodium coenophialum (syn. Acremonium coenophialum), and photosensitization in pastures contaminated by toxigenic Pithomyces chartarum. Other mycotoxicoses in grazing cattle include slaframine toxicity in clover pastures infected by Rhizoctonia leguminicola and diplodiosis in cattle grazing in corn stubbles. The mycotoxicoses caused by contaminated concentrated food or byproducts in cattle include poisoning by toxins of Aspergillus clavatus, which contaminate barley or sugar beetroot by-products, gangrenous ergotism or dysthermic syndrome caused by wheat bran or wheat screenings contaminated with Claviceps purpurea, and acute respiratory distress caused by damaged sweet potatoes (Ipomoea batatas). The main mycotoxicosis of horses is leukoencephalomalacia caused by the fumonisins B1 and B2 produced by Fusarium spp. Poisoning by C. purpurea and F. elatior infected by N. coenophialum has also been reported as a cause of agalactia and neonatal mortality in mares. Slaframine toxicosis caused by the ingestion of alfalfa hay contaminated by R. leguminicola has also been reported in horses.

Sago haemolytic disease: towards understanding a novel food-borne toxicosis.

Sago haemolytic disease is a rare but sometimes fatal disease found primarily in the coastal regions of Papua New Guinea and among groups in which sago is a primary source of carbohydrate. It has been known since 1961 and fungi consistently have been suspected of being involved. Investigations carried out on stored sago and samples recovered from poisoning episodes have failed to indicate the consistent presence of mycotoxins. However, fungi (especially Aspergillus, Fusarium, Penicillium, Trichoderma) with strong haemolytic activity have been associated with sago, particularly when stored in open-weave baskets and sago-leaf-wrapped bundles. The haemolytic activity has been attributed to fatty acids (principally oleic, palmitic, linoleic) contained primarily in the fungal hyphae. It is hypothesized that when these acids are released through hyphal breakdown during digestion and are present in individuals with a low serum albumin level, free fatty acid excess occurs resulting in red cell membrane destruction and intravascular haemolysis. In extreme cases, blood transfusion is required. Methods of storage providing high levels of access to oxygen favour the development of fungi: eg, leaf-encased bundles and open-weave storage favour growth over that seen in starch stored under water, such as in earthen vessels. Ensuring storage does not exceed 3-4 weeks, encouraging anaerobic conditions of the starch and maintaining protein nutrition in communities where sago is relied upon should alleviate outbreak episodes.

Incidencia de fumonisinas en piensos para cerdos y caballos / Occurrence of fumonisins in feed for swine and horses

Antecedentes. La contaminación por fumonisina B1 (FB1) y B2 (FB2) y por el conjunto de micotoxinas en alimentos y piensos puede causar efectos diversos sobre los productos agrícolas y la salud de los animales. La contaminación afectó de modo predominante al maíz y a los alimentos y piensos derivados. Objetivos. En este estudio, efectuada en Portugal, se examinó la incidencia de fumonisinas en muestras de pienso mixto para cerdos y para caballos. El período de la revisión abarcó de 2007 a 2010. Métodos. Mediante cromatografía líquida de alta resolución (HPLC) se analizaron 363 muestras, 258 de pienso porcino y 105 de pienso equino. El límite de detección fue de 50μg/kg para FB1 y de 100μg/kg para FB2. Resultados. Los resultados globales fueron una incidencia de contaminación por fumonisina B1 (FB1) del 13% desde 2007 a 2010. Se detectó FB1 en alrededor del 17% de las muestras de pienso porcino, siendo más frecuente en 2010 (32,9%). En dicho año, los niveles variaron entre 66,7 y 3.815,5μg/kg. En 2010 sólo se detectó contaminación por fumonisina B2 en muestras de pienso para cerdo (seis muestras, con una variación de 104,0 a 467,2μg/kg) y en muestras de pienso para caballos (una muestra). Conclusiones. Aunque los resultados de este estudio indican un aumento de la incidencia durante los años examinados, no constituye un riesgo para la salud de los animales, ya que los valores no superan los recomendados por las directrices de la Comisión Europea(AU)

Background. Fumonisin B1 (FB1), fumonisin B2 (FB2), and overall mycotoxins feed contamination may cause several effects on crops production and animal health. The contamination occurred predominantly in corn and corn-based foods and feeds. Aims. This survey intends to provide the occurrence of fumonisins in swine and equine mixed feeds in Portugal, making an overview from 2007 to 2010. Methods. A total of 363 samples were analyzed, 258 from swine feed and 105 from horse feed with HPLC method. The detection limit was 50μg/kg for FB1 and 100μg/kg for FB2. Results. The overall results were 13% of FB1 occurrence from 2007 to 2010. FB1 was detected in about 17.0% of swine feed samples, being more frequent in 2010 (32.9%). In this year (2010) levels ranged between 66.7 and 3815.5μg/kg. FB2 occurred only in 2010 in swine feed (6 samples, ranging between 104.0 to 467.2μg/kg) and in horse feed (1 sample). Conclusions. This represents an increase in occurrence through the analyzed years, but this may not be a threat to animal health, once the values were below the recommended guidance values from European Commission(AU)

Effects in food-producing animals.

Unexplained disease outbreaks in farm and domestic animals have suggested the likely presence of mycotoxins in feeds for many years. The manifestations of mycotoxicoses in the field are frequently nondescript and potentially have many contributing factors, which are often difficult to define. Nevertheless, toxigenic moulds were implicated in, and sometimes proven to be the cause of, animal disease in field outbreaks long before the toxins were discovered. The development of methods for the chemical analysis of mycotoxins in feeds and animal tissues has contributed to an improved understanding of the dose-response relationships of farm animal diseases associated with exposure to aflatoxins, fumonisins, ochratoxin A, deoxynivalenol, zearalenone, and ergot alkaloids. In all cases the effect of mycotoxins on animal performance is potentially a major problem for farmers regardless of their scale of operation. Reduced growth, decreased egg and milk production, lower reproductive efficiency, and increased susceptibility to stress are all potentially devastating consequences of mycotoxin exposure. Thus, being aware of the outward signs that might signal the involvement of a mycotoxin in an animal performance problem is the first step to minimizing potential adverse impacts. The target organ affected can provide important clues to involvement of a specific mycotoxin, in which case understanding the toxicokinetics and toxicology will assist in minimizing the cost and maximizing the effectiveness of interventions. The primary objective of this chapter is to provide information that will aid in the field identification of the possible involvement of a mycotoxin in an animal production problem. In conjunction with the information provided in the other chapters, this information will assist farmers in making decisions that will minimize losses due to diseases induced by mycotoxins.