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Despite the unfavourable influence of mycotoxins on human and animal health and few toxicological aspects that have been documented, about these biologically active substances has not been explored. Aiming at more knowledge and a better understanding of the effects and mechanism of mycotoxin action in mammals would provide the basics for developing strategies to restrain different mycotoxicoses. One of the processes not fully understood is biotransformation, to which mycotoxins are subjected the animal organism. Biotransformation is the conversion of mycotoxins to non-toxic metabolites and occurs mostly in the intestinal mucosal membrane and liver, although other tissues and systems also take part in this process. Mycotoxin biotransformation reactions can be considered bioinactivation or detoxication, but mycotoxin biotransformation processes could also result in products more toxic than the mycotoxin. It can be concluded from research studies that our knowledge of mycotoxin biotransformation is scarce.

Deoxynivalenol is one of mycotoxins that are most frequently determined in animal feed manufactured in Poland. The examination of histopathological lesions concomitant with deoxynivalenol intoxication is difficult because of the common, often synergistic, reaction of this mycotoxin with other toxins, such as zearalenone or ochratoxin A, which has a strong nephrotoxic activity. The possibility of estimating histopathological lesions in the course of intoxication with pure toxin at various doses is therefore of interest. Dosages used in this experiment relate to clinical cases observed in feeding the animals with whole ration feed obtained by processing feedingstuffs contaminated with Fusarium moulds. However, concerning the fact of one-shot administration of clinically pure toxin, the main question was if it was a sufficient dose to cause changes in the histopathological picture of gastrointestinal tract organs. The experiment was carried out on 12 nursery pigs of mixed breed (Polish White Large x Polish White Ear-pendent) with an average body weigh of 35 kg. The experimental nursery pigs were divided into 3 groups: group I (n=4)--control; group II (n=4)--DON administered at a dose of 0.2 mg/kg b.w.; group III (n=4)--DON administered at a dose of 0.4 mg/kg b.w. After slaughter of the animals, macroscopic examination was performed and segments of duodenum, jejunum, ileum, liver and mesenteric lymph nodes were sampled and assigned for histopathological examination. The results obtained equate to the clinically observed signs in swine production involving some nutrient metabolism disturbances in the gastrointestinal tract in the course of deoxynivalenol mycotoxicosis. Histopathological examination of segments of the duodenum, the jejunum, the ileum, the liver and the lymph nodes indicate that the regressive lesions are more expressed in the experimental group treated with the highest concentration of deoxynivalenol.

Fusarium spp. moulds are common in moderate climate regions of North America, Asia and Europe. They produce hepatotoxic and nephrotoxic mycotoxins, acting like estrogens, impairing hemopoesis and immunosuppressing. Actively dividing skin cells, lymphatic tissue, haemopoetic tissue and gastrointestinal tissue are the most sensitive for these trichothecenes action. The mucosal membrane of the gastrointestinal tract is the first barrier of the organism contacting with foreign antigens like feed proteins, natural toxins, saprophytic and pathogenic microflora and mycotoxins. The aim of this study was to perform histological estimation of the porcine small intestine after short term intoxication with low doses of deoxynivalenol (DON), T-2 toxin (T-2) and zearalenone (ZEA) obtained from wheat naturally contaminated with Fusarium moulds. Experimental pigs (n=5) were fed for 14 days feed containing DON, T-2 and ZEA (28.9, 11.5 and 33.2 microg kg(-1) of feed). On the last day of the experiment, the animals were euthanised and samples of the jejunum were collected for histological examination. In the experimental pigs, normally developed intestinal villi and crypts were found. However, number of acidophilic granulocytes in the mucous membrane and decreased numbers of goblet cells, increased numbers of endothelial lymphocytes and numerous plasma cells in intestinal epithelium was observed. On the surface of the intestinal epithelium the glycocalyx was poorly developed. The results obtained suggest that short term intoxication with low doses of DON, T-2 and ZEA does not cause significant changes in the histological structure of the small intestine in the pig. However, low concentrations of DON, T-2 and ZEA probably influence enterocytes metabolism and evoke inflammation of the mucous membrane of the small intestine.

Zearalenone (ZEA) is a member of macrocyclic lactons family. It is a toxin--phytosteride produced by fungi of Fusarium ssp. genus. Zearalenone contaminates food and animal feeding stuffs and its destruction is difficult. It requires application of particular compounds that would bind zearalenone in the feed or feeding stuff or in the gastrointestinal tract and decrease its bio-accessibility. It should also fulfil all the safety requirements regarding the plant supplements and animals that are fed with this feed. The aim of the study was to estimate if the feed supplemented with different doses of zearalenone and zearalenone destructor causes changes of the metabolic profile in gilts. The results obtained show that applied destructor did not cause negative haematological and biochemical changes in the blood of the gilts examined. It can be suggested that it is a safe feed supplement pigs in prevention of zearalenone micotoxicosis.

Both earlier investigations and complete formulas of pet food for dogs show that professionally prepared pet food is based in 30% on the material of the plant origin. Our own investigations prove that animal feeding stuffs of the plant origin are very often vectors of many undesirable substances (including micotoxins) that are unfavourable for carnivores. Zearalenone is a micotoxin, which frequently occurs among them. It was revealed in pet food in quantities from 5.0-299.5 microg/kg. It is a very dangerous xenobiotic because of its quick and easy absorption in the organism after per os application in monogastric animals. It is also a sterid and despite its plant origin it binds estrogen receptors in the reproductive tract and causes its hypo- and dysfunction. It is clearly visible in young, growing organisms and those during the menopause. In bitches, dysfunctions of the reproduction system, such as: endometritis-pyometra syndrome, prolonged oestrus, ovarian cysts and others are often found. It is supposed that specific for this species hormonal regulation of the reproduction processes based on the long progesterone and prolactin cycles, and on high sensibility to estrogens plays an important role in the etiopathogenesis of these dysfunctions. The application of hormones in bitches in therapeutic and biotechnical (contraception) purposes are the other factors, which should be taken into account in this aspect. There are some suggestions that therapeutic management, unfortunately connected with mistakes in the medical art, is often a cause of pathological condition in a reproductive organ in bitches. However, another reason of these disorders may be that bitches take zearalenone with the commercial pet food. The long-lasting intake of the feed with a low dose of this micotoxin may be the factor, which complicates hormonal regulation of the reproduction processes and is the cause of many disorders. Our own pilotage investigations showed that application of zearalenone at a dose of 200 microg/kg b.w. for 7 days leads to apoptotic-like changes in granule cells in the bitch reproductive system, atresia of follicular cells and oedema and hyperplasia of the oviductal and uterine cells. They could also indicate a follicular phase of the oestrus cycle in bitch. However, it did not take place.

One of the possibilities for estimating pancreas activity is the estimation of zymogene granule content in pancreatic follicular cells. In the present study, the degree of pancreatic activity was measured in piglets from sows receiving enzymatic stimulating complex throughout pregnancy and during the lactation period. The pancreas was collected for ultrastructural examination from 1-day-old and 21-day-old piglets. The enzyme preparation influenced the ultrastructural structure of the piglet pancreas, but the secretory cells in these animals did not confirm a more intensive course of creation and maturation processes. The accumulation of granules in extra-secretory pancreatic cells was observed, with a large volume of these granules and granular crinophagy observed in older piglets. The findings indicate a slow process of granule release, which may be the result of overproduction, lower requirements for enzymes contained in the granules, or both.

Zearalenone (ZEA) is a mycotoxin produced by Fusarium. It evokes disruptions in sex cycle and changes in the morphology of the reproductive organs in pigs. The morphology and ultrastructure of the small intestine mucosa were assessed after the course of the experimental zearalenone mycotoxicosis. During the experiment, pigs were fed feed containing low doses of ZEA. The experiment lasted 7 days and it was carried out on sexually immature gilts that were divided into 3 groups: control group (C) and 2 experimental groups (E1, E2; n=8). Groups E1 and E2 were given ZEA every day at a dose of 200 and 400 microg/kg b.w. The samples of tissues were taken for examinations after the slaughter on the last day of the experiment. No significant changes in the morphology of the intestinal mucosa were found in the experimental animals. Increased activity of the goblet cells and high content of mucinogen vesicles, lymphocytic infiltration, increased activity of endocrine cells and the presence of Paneth cells on the bottom of intestinal crypts, which sugest mobilisation of the local defence mechanisms in the intestinal mucosa, were obseved in group E2.

Contamination of feed with zearalenone (ZEA) is still a serious problem in farm animals feeding, especially in gilts, sensitive to this compound. The relative failure of current methods of decontamination and quality control lead us to look for new techniques. The commonly accepted method for breaking down ZEA was performed in controlled temperature and time conditions. Various sodium carbonate doses (0.5 - 4%) were added to feed naturally contaminated with ZEA (ZEA biosynthesis by F. graminearum isolates). These doses were found to be effective in in vitro studies. The addition of 2% sodium carbonate gave the best results in reducing the phytoestrogen in the feed.

The aim of the monitoring of zearalenone presence in the blood plasma of women with neoplastic lesions in the reproductive tract was to asses whether the phytosteride is noted in the patients blood and whether the correlation exists between its presence and the incidence of particular neoplasm. The presence of zearalenone or its metabolite--alpha-zearalenole, was noted in 13.51% of the examined women. In 60% of the patients with the confirmed presence of the xenobiotic it was noted in the lowest concentrations. These patients had neoplastic lesions of Carcinoma corpus uteri type.

Among large husbandry animals, swine are the most predisposed to zearalenone (ZEA) intoxication, mainly because cereal is an important component of their diet. Studies performed so far (in vivo, in vitro) suggest that ZEA and its metabolites, which may appear due to ZEA biotransformation (especially alpha-zearalenole; alpha-ZOL), can modify signaling cascades of endogenous sex steroids, through either receptor or non-receptor mechanisms. Of all age groups of swine, immature gilts are particularly predisposed to zearalenone intoxication, as manifested by the occurrence of genital tract tissue dysfunction on exposure to ZEA. The intensity of the adverse effects observed at either systemic or local level in gilts, when compared to sexually mature swine females, suggest that specific age-dependent physiological conditions may exist, which determine the high sensitivity of gilts to exogenous estrogen-like compounds, including ZEA.

Zearalenone (ZEA) is an undesirable substance in feed materials and feed of plant origin. It is an example of the micotoxin that causes disturbances in the functioning of the reproductive system. The wide range of plant compounds in pet food means that ZEA may frequently have a negative effect on pet reproduction. An assessment of the influence of ZEA on the granulosa and theca cells of the ovarian follicle in bitches in vitro was carried out. The co-culture of the ovarian follicles was incubated for 72 hours with the addition of 12.5 ng/ml and 25.0 ng/ml of ZEA. Numerous vacuoles in the cytoplasm of the granulosa cells were noted in the culture with the addition of 25.0 ng/ml of ZEA. Preliminary investigations suggest negative effect of ZEA on the granulosa cells in bitches in vitro.

The aim of the study was to determine the influence of experimental zearalenone (ZEA) mycotoxicosis on the ultrastructure of ovaries in bitches receving zearalenone for 100 days per os in the anestrus phase. Experiment has been conducted on 9 sexually mature clinically healthy bitches. The sexually mature animals aged 1-3 years were in anestrus. The dogs have been divided into three groups: EI and EII, receiving ZEAper os in two dosages (25 microg/kg and 50 microg/kg b.w.) and control animals which received placebo per os. On the last day of experiment, ovariohysterectomy was performed in all the bitches and the uterine samples were submitted to ultrastructural analyses. The study has revealed that long lasting administration of higher dose of zearalenone causes ultrastructural changes in the granular layer of ovarian follicles, which showed due to their biological activity decrease. The changes in the granular layer, atrophy of intercellular connections and the appearance of intercellular spaces can stand for reduced activity of this layer. Changes in morphology of mitochondria, rough endoplasmic reticulum and Golgi apparatus sugest ZEA influence on cell metabolism and secretory processes. It seems therefore that in bitches and other monogastric animals, intoxications induced by this mycotoxin causes ultrastructural changes in granular cells of ovarian follicles.

The increasing interest in enzymatic growth promoters prompted this investigation of the effect of an enzymatic stimulating complex on selected hematological and serum biochemical parameters in boars. The enzymatic complex [five proteases (proteinases-endopeptidases) and two peptidases (exopeptidases) obtained by fermentation from Streptomyces fradiae] was added to diets for three months, at initial doses of 90 (group E1) and 120 (group E2) g/ton feed for the first seven days followed by 40 and 60 g/ton, respectively, in the subsequent weeks. The evaluation was based on selected hematological (RBC, WBC, HCT (Ht), HGB (Hb), MCV, MCH, and MCHC) and biochemical (AST, ALT, AP, Ca, Mg, urea, cholesterol, creatinine, inorganic phosphorus, and oxyglucose) parameters determined before and after the experimental period. The reported values were within physiological norms. Statistical differences were found between experimental groups with respect to WBC, HCT (Ht), MCV, MCH, AP, Ca, Mg, creatinine, and inorganic phosphorus. The study results indicate that the complex of proteolytic enzymes administered to boars caused no negative changes in their metabolic profiles. The statistically different hematological and serum biochemical parameters, while within normal limits, point to an early stage of microcytic anemia and heightened agitation that could be the result of intensified nitrogen metabolism.

Zearalenone (ZEA) is a macrocyclic lactone, estrogenic, diet-depending and fusaric micotoxin, which is produced on many kinds of cereals and feeds in the favourable conditions of humidity and temperature. The structure of ZEA is similar to the structure of estrogens and it enables binding to the estrogenic receptors. The stimulation of protein synthesis in the cells of the reproductive system, which causes intensification of cell proliferation, is one of the effects of ZEA actions. Oedema and vulva reddening are the clinical, external signs of ZEA intoxication in pigs. The aim of this study was to designate the degree of reproductive cell proliferation after low doses of ZEA were applied per os in sexually immature gilts with simultaneous monitoring of zearalenone and alpha-zearalenol levels in peripheral blood. The following were observed in the gilts examined fluctuations of zearalenone and alpha-zearalenol levels in blood, which were connected with entero-hepatic circulation and also numerous histopathological changes in ovarian follicle structure. These changes were present in the reproductive system of sexually immature gilts with a big contribution of PCNA-positive cells. The studies show that zearalenone application in sexually immature gilts caused ovarian follicle atresia and apoptoso-like changes in granule cells. Intensified cell proliferation, which was expressed with the growth of PCNA index, was observed in uterus and oviduct.

The aim of the study was to determine how a low dose of zearalenone applied orally for eight days influences the level of zearalenone (ZEN) and alpha-zearalenole in blood plasma and causes the occurrence of histopathological changes in the cells of the ovarian follicles in sexually immature gilts. The animals were divided into 2 groups (control, C; n = 4 and experimental, E; n = 4). The gilts from group E were treated daily with zearalenone at a dose of 200 microg/kg b.w. The level of zearalenone and alpha-zearalenole (ZON as the sum of the levels of both zearalenone and alpha-zearalenole) was measured daily. On day eight of the experiment the animals were sacrificed and their ovaries were taken for histopathological examination. The tissue sections obtained were HE- and PAS-stained according to McManus. The presence of PCNA antigen was also estimated. The highest concentration of ZON was noted on day 5 in group E (8.16 +/- 2.49 ng/ml). External estrus symptoms without standing reflex were observed in group E on day 4. In group C there were no pathological changes in the ovaries. In group E, a few ovarian follicles were found, but they were located in the cortical layer. They were filled with a liquid substance rich in protein and without the granulosa layer. There was disintegration with apoptotic-like changes of the PCNA-negative cells in the granulosa layer of single mature follicles. On day 4 the dose of zearalenone caused disturbances in the process of development and maturation of some of the best developed ovarian follicles. This probably occurred through the activation of on apoptosis-like process of the granulosa cells with simultaneous manifestation of estrus without standing reflex.

The research was aimed at determining the impact of the experimental oral administration of zearalenon on the uterus in bitches. The study was carried out on 9 sexually mature 1 to 3 year-old bitches that were divided into three groups: two experimental ones and a control group. The experimental animals were orally administered zearalenon at 25 microg/kg BW (body weight) (group DI; n=3) and 50 microg/kg BW (group DII; n=3) throughout 100 days while the control bitches (group K; n=3) were administered placebo. After the period of 100 days, ovariohysterectomy was performed, and the uterine samples were submitted to histopathological and immunohistochemical examinations in order to determine the structure of the wall and the presence of PCNA antigen. In the experimental animals, the histopathological examinations revealed regressive lesions, such as degeneration and atrophia within the endometrium and myometrium, and local circulatory disorders, i.e. edema and extravasation. These lesions were not reported in the controls. In the bitches administered zearalenon, the tissues did not express any proliferative activity as determined by the presence of PCNA. It is assumed that, following the administration of zearalenon for 100 days orally to bitches, disruption of the structures within the wall of the uterus (i.e. degeneration, atrophy, edema, and extravasation within the endometrium and myometrium) develops. This research proves that zearalenon ingested by bitches may lead to dysfunction of the uterus and cause disruption of its structures.

The immunological, haematological and biochemical analyses of blood plasma in bitches with 50 days lasting induced zearalenone micotoxicosis were carried out. It can be indirectly suggested that the inhibition of the humoral reaction of the organism, stimulation of detoxification effect in the liver and decreased cellular answer took place.

The aim of the study was to evaluate the influence of low dose (LOEL - lowest observed effect level) of zearalenone (200 microg/kg b.w.), applied per os for 7 days (short-term intoxication), on sexual behavior, concentration of the examined xenobiotic and its metabolite and selected estrogens in sexually immature gilts: ovariohysterectomised (group D1) and intact (group D2) animals. Clinical signs of oestrus (reddening, oedema and hyperaemia of the vulva and serorhoea from the reproductive tract--lack of standing reflex) were obserwed in group D1 on day 6 and in group D2 on day 4 of the experiment. Laboratory analyses of blood plasma were carried out determine the presence of zearalenone and alpha-zearalenole. They revealed an increase in the level of alpha-zearalenol before the oestrus, decrease in total amount of both examined substances on day when the oestrus appeared and increase in the level of both examined xenobiotics in the post oestrus period together with the higher share of zearalenone. Medium concentrations of estrone and estradiol within the borders of method determination in the majority of periods examined. Higher levels of estrone (32.0 pg/ml) were found on day 4, in the group D2 and estradiol (6.5 pg/ml) on day 6 in the D2 group. The presents study revealed that zearalenone applied per os at LOEL dose causes the incidence of apparent sexual readiness (without standing reflex) in sexually immature gilts with the somatically immature reproductive system.

Purpose Keratoconus (KTCN) is a non-inflammatory, usually bilateral disorder of the eye which results in the conical shape and the progressive thinning of the cornea. Several studies have suggested that genetic factors play a role in the etiology of the disease. Several loci were previously described as possible candidate regions for familial KTCN; however, no causative mutations in any genes have been identified for any of these loci. The purpose of this study was to evaluate role of the collagen genes collagen type IV, alpha-1 (COL4A1) and collagen type IV, alpha-2 (COL4A2) in KTCN in Ecuadorian families. Methods COL4A1 and COL4A2 in 15 Ecuadorian KTCN families were examined with polymerase chain reaction amplification, and direct sequencing of all exons, promoter and intron-exon junctions was performed. Results Screening of COL4A1 and COL4A2 revealed numerous alterations in coding and non-coding regions of both genes. We detected three missense substitutions in COL4A1: c.19G>C (Val7Leu), c.1663A>C (Thr555Pro), and c.4002A>C (Gln1334His). Five non-synonymous variants were identified in COL4A2: c.574G>T (Val192Phe), c.1550G>A (Arg517Lys), c.2048G>C (Gly683Ala), c.2102A>G (Lys701Arg), and c.2152C>T (Pro718Ser). None of the identified sequence variants completely segregated with the affected phenotype. The Gln1334His variant was possibly damaging to protein function and structure. Conclusions This is the first mutation screening of COL4A1 and COL4A2 genes in families with KTCN and linkage to a locus close to these genes. Analysis of COL4A1 and COL4A2 revealed no mutations indicating that other genes are involved in KTCN causation in Ecuadorian families.

The present study deals with the influence of experimental ZEA mycotoxicosis on histopathological lesions in ovaries of bitches, which were administered zearalenone per os during anestrus phase for one hundred days. The experiment was performed on 9 sexually mature, clinically healthy bitches. The animals assigned into two experimental groups received zearalenone per os at two doses, 25 microg/kg b.w. and 50 microg/kg b.w., respectively: the bitches from control group received placebo per os. On the last day of zearalenone intoxication, the bitches were ovariohystorectomized. Histopathology and immunohistochemistry were performed. The study revealed that zearalenone and its metabolites caused profound regressive lesions: granular cells degeneration and atrophy. Numerous edemas and blood extravasations were also found. The intensity of these changes was significantly dose dependent. Furthermore, in ovarian cells and tissues of both experimental groups, no reaction for PCNA antigen was observed. In conclusion, zearalenone and its metabolites exerts unfavorable effects on the morphology of ovaries in bitches.