M. Tech. / Fusarium species are common contaminants of maize and are also capable of producing mycotoxins, in particular the fumonisin. These are implicated in animal and human mycotoxins fumonisin B1 (FB1) for example, has been associated in the aetiology of oesophageal cancer in South Africa and other parts of the world, i.e., China and Iran. Because maize is the staple diet of the South African rural population, this study was designed with the aim of monitoring Fusarium spp. and FB1 in the food of rural people of Venda, Limpopo province of South Africa, during the course of processing maize into porridge which gave a means of estimating dietary exposure to this mycotoxin. Measurement of fumonisin in the excreta of these people allowed a determine of the extent to which FB1 the body is actually exposed to the mycotoxin.Fumonisin B1 has been identified as a major fungal contaminant on maize, especially in the home grown crops intended for human consumption. Thus the rural population of Limpopo Province is at high risk from FB1 exposure and it is therefore of importance to assess this exposure by the analysis of suitable samples.It can be seen that levels of FB1 in maize from Venda are quite high, as several of these samples had exceeded levels above 1750 μg/kg as recommended as maximum tolerance levels by theEuropean Commission. It is equally seen that a much higher proportion of this mycotoxin was destroyed by processing maize to porridge. And because porridge and other maize-based products are usually consumed on a daily basis, the low levels found in the present study must not be under-estimated, as such levels may accumulate over time and cause more severe chronic effects in humans. When setting daily tolerable levels of FB1 in foods in South Africa, it is imperative to take into account the food habits, especially those within the rural communities

>Magister Scientiae - MSc / Fi1sarium verticillioides is a very important mycotoxin-produeing fungus associated with maize. Fverticillioides produces a group of mycotoxins known as fumonisins under suitable environmental conditions. A series of studies was designed to provide information regarding some of the factors associated with the production offumonisin B1 (FB1) in maize patties and MYRO liquid medium. Our investigation together with previous studies have detailed the important influence of several factors on the production of fumonisins by F verticillioides strains. To understand why these strains are able to produce these toxins, an investigation into the complex interaction that occurs between biotic and abiotic parameters and their impact on fumonisin production was necessary. The results reflect the interacting factors and the intraspecific differences between strains, which may also be present in field conditions. The parameters that were varied under a predetermined set of culture conditions, included initial moisture content of maize patty cultures, temperature, initial pH and the addition of the fumonisin precursors, L-alanine and L-methionineto the cultures. Investigations into the three-way interactions of initial maize patty moisture content (30 ml water to 30g of maize), L-methionine (0.3 %) and temperature (25°C), resulted in the highest yield ofFB1 (5777.26 μgig) produced by MRC 4316. In contrast, MRC 826 was negatively affected, producing lower levels ofFB1 (3492.24 μg/g), compared to MRC 4316 at an initial moisture content (20 ml water to 30 g maize), L-methionine (0.3 %) and 25 °C. An American strain of F verticillioides MRC 7424 (= NRRL 13616), produced the highest levels of FB, (116 μg/ml), while the South African isolates, MRC 4316 and MRC 826, produced lower FB1 levels (93 and 62 μg/ml, respectively) in MYRO liquid medium. In general, FB1 production in maize patty cultures far exceeded levels obtained in liquid shake cultures. It appears that not only the ability of a particular strain of F. verticillioides, but the interaction of a variety of physiological and nutritional factors and the culture medium, are important in the production of FB,. Thus, variation of a single factor such as temperature under field conditions due to seasonal change, may therefore have a major effect on fomonisin production. A chain reaction may occur when changes in moisture, pH, etc. take place, which may influence fumonisin production further. Lyophilisation of fungal cultures proves to be an excellent method to preserve a wide range of fungi over long periods of time. It is, however, necessary to determine the viability of conidia stored in lyophilised vials at 4 ° Con a regular basis. At present, plate count methods remain the most valid technique for the detection of the viability of lyophilised conidia. Membrane-permeant nucleic acid-binding dyes (FUN-I) are viability stains that are relatively new flourescent probes for assessing the viability of metabolically active yeast cells. The purpose of this study was to microscopically determine the viability oflyophilised conidia of Fusarium and A lternaria species, using the yeast, Saccharomyces cerevisiae, as a control. FUN-1 viability stain was compared to two other staining methods, i.e. ethidium bromide (EB) and methylene blue (MB) and the viability of the conidia was compared to colony-forming units (CFU) on solid media as a control. For the purpose of determining or screening for percentage viability in a specific inoculum, results indicate that EB can be used in the case of lyophilised conidia, and MB in the case of freshly harvested conidia. Although FUN-I are recommended as a good way to determine the cell viability of a fungus, it needs relatively complicated procedures and has a time limit in which the stain can be used. The result of this study emphasize that the use of dyes to determine viability of lyophilised conidia require a critical definition of protocols for a specific fungal species, and that a good correlation with CFU needs to be demonstrated. The findings of this study could find useful applications in various studies on living and dead conidial populations. The diverse toxicological effects of fumonisins m animals and plants raised the possibility that fumonisins may also inhibit the growth of filamentous fungi. This study investigated the antifungal activity of FB1 to some h1sariu111 and other fungal species. The sensitivity of these fungi was tested by an agar-diffusion method on PDA plates. FB1 inhibited the myceliaJ growth of five of the nine fungi tested. The FB1-producing Fusarium species isolated from maize, i.e. F verticil/ioides, F glohosum and F proliferatum were resistant to FB1 even though a small inhibition zone at the highest FB1 concentration of 40mM was noted in the case of F. proliferatum. However, amongst two non-producing Fusarium spp. also isolated from maize, one (F subglutinans) was resistant and one (F graminearum) was sensitive. The most sensitive fungi tested were non-producing species not isolated from maize, i.e. A lternaria alternata, Botrytis cinerea and Penicillium expansum. The minimum inhibitory concentration ofFB1 ranged between 0.25-0.SmM for A. alternata, 1-SmM for P. expansum and B. cinerea and 5-1 OmM for F. graminearum, while the other fungi tested showed no sensitivity to FB1. This is the first report on the antifungal activity ofFB1 to filamentous fungi. Another study investigated the effect of FB1 on the germination of freshly harvested conidia of Fusarium and some other fungal species. The FB1 -producing F'usarium species isolated from maize, i. e. F vertici llioides, F. globosum and F. prolifer alum showed a decrease in germ tube length with an increase in FB1 concentrations. This indicated that these fungi can tolerate their own toxic metabolite to a ce11ain extent. However, amongst the two non-fumonisin producing Fi1sarium spp. examined, i.e. F. subglutinans and F. graminearum, isolated from maize, F. subglutinans was induced to genninate faster in the presence ofFB1 but soon developed stunted germ tubes, while F graminearum developed shorter germ tubes compared to the control cultures. The most sensitive fungi tested were species not isolated from maize, i.e. A. alternata, B. cinerea and P. expansum, which did not germinate at higher FB1 concentrations at all. Statistical analyses showed that the inhibiting effect of FB1 was highly significant (P <0.001). The conidial germination bioassay was more sensitive in the detection of the antifungal activity ofFB1 than the petri dish bioassay. The minimum inhibitory concentrations of FB1 for visible mycelial growth were closely comparable to those obtained from conidial germination. Results of these studies provide considerable information on the parameters affecting the production of FB1 and will be of great benefit in further studies focussing on fumonisin prodnction.

The principal objective of this investigation was to evaluate the effects of mycotoxin contaminated diets (deoxynivalenol (DON)), aflatoxin B1 (AFB1), and fumonisin (FUM)), with or without the use of a commercially available deactivating compound (DC), in young pullets and replacement laying hens on performance, reproductive, serological, and histopathological parameters. In trial 1, experimental treatments consisted of control, low toxin (1 µg DON/g + 1 µg AFB1/g), and high toxin (2 µg DON/g + 2 µg AFB1/g) diets. Pullets fed the high toxin diet had reduced (P<0.05) body weights compared to control and low toxin diets at d 14, 35, 49, 56, and 63. At d 21 and 28, there was a significant interaction observed between mycotoxin and DC inclusion in body weights. Following necropsies (d 35 and 65), relative liver weights and histopathological liver tissue damage were increased (P<0.05) in pullets fed high toxin diets when compared to control and low toxin diets. Relative kidney weights were increased (P<0.05) due to high toxin diet at d 65. Expected negative effects of toxin administration on titer development were not observed. The only interaction observed between mycotoxin administration and DC inclusion in trial 1 was on body weights. In trial 2, experimental treatments consisted of control, DON (9 µg/g) challenge, AFB1 (2 µg/g) + FUM (54 µg/g) challenge, and a mixed challenge (6 µg DON/g, 1 µg AFB1/g, and 27 µg FUM/g). All mycotoxin diets fed to hens negatively influenced (P<0.05) feed efficiency for the trial period spanning weeks 6 through 10 when compared to control diets. Egg production was not affected (P>0.05) by all mycotoxin diets weeks 6 through 10. Relative weights of the liver and kidney were increased (P<0.05) by AFB1+FUM challenge weeks 4 and 9 compared to control diet. The data reported in this study demonstrate that dietary DON and / or AFB1+FUM influence some performance, reproductive, histopathological, and egg quality traits, but by and large, replacement layer pullets seem to be relatively resistant to the mycotoxins evaluated in this trial at the described levels of administration.

Les mycotoxines telles que la fumonisine B1 (FB1) produites par les champignons du genre Fusarium sont particulièrement préoccupantes pour la filière maïsicole. L’ensilage de maïs est un processus de fermentation naturel susceptible de favoriser l’évolution des teneurs en FB1. La maîtrise du risque de contamination par la FB1 et la recherche de moyens permettant la décontamination des ensilages est donc nécessaire. L’objectif de ce travail est de caractériser le devenir de la FB1 dans les ensilages de maïs grain et de mettre en évidence l’existence d’agents microbiens capables de dégrader cette toxine. Pour cela, des mini-silos contenant du maïs grain naturellement contaminé en FB1 provenant de différents parcelles et issus des deux années de récolte ont été préparés. La stratégie analytique basée sur le dosage de la FB1 libre et la FB1 complexée par HPLC-MS/MS a révélé une diminution significative de la teneur en FB1 totale qui ne peut être attribuée à un mécanisme de complexation et résulte d’un mécanisme de dégradation. La recherche du microbiote associé à la dégradation de la FB1 a été réalisée par deux approches complémentaires : Une analyse métagénomique combinant l’extraction sélective de l’ADN microbien et le séquençage haut débit «shotgun» afin de comparer la diversité taxonomique et fonctionnelle d’un ensilage dégradant la FB1 et d’un ensilage moins dégradant. En parallèle, un criblage de microorganismes cultivables capables de métaboliser la FB1 a été conduit et a permis de confirmer les résultats de l’analyse globale. Ce travail apporte une première image du microbiote potentiellement associé à la dégradation de la FB1, ainsi que des activités microbiennes responsables. / Fungi of the genus Fusarium are one of the major contaminants of maize that can produce mycotoxins, such as the fumonisin B1 (FB1). Maize silage which is based on the fermentation of whole crop plant or grains is considered the main source of monogastrics and cattle feeding in Europe. The ensiling process could favor changes in FB1 content; however this has scarcely been documented. This led to questioning regarding the possibility of managing the microbiota during ensiling in order to reduce the level of mycotoxins exposure and improve feed quality. The aim of this work is to study the fate of FB1 during ensiling process of high moisture maize grain and to identify an endemic microbiota capable of degrading FB1. Laboratory scale silages were prepared with naturally contaminated FB1 grains from two cropping years. An analytical procedure allowed assessing both free and matrix associated FB1 forms and showed a significant decrease in total FB1 content that are not linked to the presence of bound FB1. Additionally, our data showed that the FB1 content decrease was mainly due to a degradation process. Identification of a potential microbiota responsible for FB1 degradation was conducted. A metagenomics approach combining a selective microbial DNA extraction and high-throughput shotgun sequencing showed microbial specific patterns between FB1 degrading and weakly degrading silage. These results were also supported by the isolation of microbial strains able to metabolize FB1. Ultimately, this work evidenced a microbiota associated to FB1 degradation and the functional diversity involved in this activity. Bacteria and yeasts have been obtained for further studies on degradation activities and their usage as silage starter.

著作権情報を一部追加（2023-06-30） / 京都大学 / 新制・論文博士 / 博士(農学) / 乙第13508号 / 論農博第2906号 / 新制||農||1095(附属図書館) / 学位論文||R4||N5408(農学部図書室) / (主査)教授 谷 史人, 教授 入江 一浩, 教授 井上 和生 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Exposure to food contaminates such as mycotoxins have been associated with a variety of animal and human diseases worldwide. In South Africa, maize is the most To further refine risk assessment in the socio-demographic heterogeneous population of South Africa, the development and evaluation of a sensitive and interactive model the Mycotoxin Risk Assessment Model (MYCORAM) proofed to be more sensitive compared to the classical probable daily intake (PDI). The development of the MYCORAM was based on mycotoxin distribution during dry milling of maize in milling fractions intended for human consumption which was superimposed on the maize intake profiles of the South African population. Although dry milling, including a degerming step, is an effective way to reduce mycotoxins, risk and exposure assessment are influenced by maize dietary intakes, gender and ethnicity. This became evident when considering FB dietary exposure in rural maize subsistence farming communities in the Eastern Cape Province, South Africa confirmed the vulnerability of this subpopulation to risk of fumonisin exposure. Specific maximum tolerated maximum levels (MTL) to safeguard these communities fall outside the international regulatory processes and need to be urgently addressed. With the complex nature of cancer development in mind, integration of basic science and nutritional epidemiology will be important to contribute to our understanding of the adverse effects of FB and to define relevant risk assessment parameters. important commercial grain crop not just economically but also as a local food commodity both commercially and in subsistence rural farming communities. In order to control and manage mycotoxin contamination in food, evidence-based risk assessment is needed that includes mechanistic and human exposure studies. From this perspective the current study was conducted and aimed in further unravelling fumonisin B1 (FB1) mycotoxin induced hepatocarcinogenesis via the disruption of the lipid metabolism. The study also critically evaluates aspects of human risk assessment due to its relevance and importance to food safety known to impact on food security. This entails mycotoxin distribution during maize dry milling and the assessment of mycotoxin exposure in the South African population and vulnerable rural communities at risk. Fumonisin B1 affects the integrity of biological membranes by altering key lipid and fatty acid parameter in plasma, microsomal, mitochondrial and nuclear subcellular membrane fractions in rat liver. Changes in the major lipid constituents entailing an increase in cholesterol (CHOL) and phosphatidylethanolamine (PE) whilst sphingomyelin (SM) and phosphatidylcholine (PC) tended to decrease. Isolated plasma membrane lipid rafts, from rat primary hepatocytes exposed to FB1 augments the intricate effects exerted on the lipid metabolism regarding CHOL, SM and PE. The disruption of lipid and fatty acid constituents, such as arachidonic acid and ceramide, are likely to be key determinants affecting growth regulatory signaling pathways relevant to the critical balance between cell proliferation and apoptosis during cancer promotion. These changes provide further evidence that FB1 induce cancer promotion by differential inhibition and/or stimulation process whereby a few resistant “initiated” hepatocytes proliferate in an environment where the growth of normal cells is inhibited. A specific lipogenic phenotype is effected by FB1 which is closely associated with cancer development and considered to occur via an epigenetic-type of mechanism. These effects are not adequately addressed in defining risk assessment parameters. / AFRIKAANSE OPSOMMING: Die blootstelling aan voedsel-kontaminante soos mikotoksienes word wêreldwyd met ‘n verskeidenheid van dierlike en menslike siektes geassosiseer. In Suid-Afrika word mielies as ‘n belangrike graanoes beskou, nie net vir die ekonomie nie maar ook as ‘n plaaslike voedselproduk beide kommersieel en vir bestaansboere in landelike gemeenskappe. Ten einde mikotoksien-kontaminasie van voedsel te kan beheer en bestuur, vereis bewys-gebaseerde risiko-evaluering wat insluit meganistiese en menslike blootstelling studies. Vanuit hierdie perspektief is die huidige studie uitgevoer en gemik op die verdere ontleding van die fumonisin B1 (FB1) mikotoksien geïnduseerde lewer-karsinogenese deur die ontwrigting van die lipiedmetabolisme. Die studie ondersoek terselfdetyd aspekte van menslike risiko-evaluering ingevolge die relevansie en belangrikheid hiervan in voedselveiligheid wat ook ‘n impak op voedselsekerheid sal maak. Dit sluit in die verspreiding van mikotoksiene gedurende die droëmaalproses van mielies en mikotoksien blootstelling in Suid-Afrika asook onder kwesbare landelike gemeenskappe. Fumonisin B1 beïnvloed die integriteit van biologiese membrane deur die modulasie van die belangrike lipied en vetsuur samestelling van plasma, mikrosomale, mitochondriale en kern subsellulêre membraan-fraksies in rot lewer. Veranderinge in die belangrike lipiedbestanddele, insluitende ‘n verhoging in cholesterol (CHOL) en phosphatidylethanolamine (PE), terwyl sphingomyelin (SM) en phosphatidylcholine (PC) geneig was om te verlaag. Geïsoleerde plasma membraan lipied vlotte (lipid rafts), vanaf primêre rot hepatosiete blootgestel aan FB1, versterk die ingewikkelde gevolge wat uitgeoefen word op die lipiedmetabolisme insluitende die voorgestelde veranderings in CHOL, SM en PE vlakke. Die versteuring van lipiede en vetsure soos aragidoonsuur (arachidonic acid) en ceramied kan beskou word as belangrike determinante wat inmeng in groei-regulerende seinbane verwant aan die kritiese balans tussen selgroei en seldood. Die versteurings verskaf verdere bewyse dat FB1 kanker bevorder deur ‘n seleksie proses wat onderskeidelike die onderdrukking en\of die stimulasie van ‘n paar weerstandige of geneties veranderde hepatosiete laat vermeerder in ‘n omgewing waar die groei van normale selle geïnhibeer word. Die spesifieke lipogeniese fenotipe wat FB1 versoorsaak hou ten nouste verband met kankerontwikkeling en die voorkoms van epigenetiese-soort meganismes word voorgestel. Hierdie oorsake word tans nie voldoende aangespreek tydens die bepaling van risiko-evaluerings limiete nie. Om risiko-bepaling verder te verbeter in die sosio-demografies heterogene populasie van Suid-Afrika, was die ontwikkeling en evalueering van ‘n sensitiewe en interaktiewe model, die “Mycotoxin Risk Assessment Model” (MYCORAM) meer doeltreffend vergeleke met die gewone waarskynlike daaglikse inname. Die ontwikkeling van die MYCORAM was gebaseer op die mikotoksien verspreiding tydens die droëmaalproses van mielies in fraksies wat vir menslike verbruik bedoel was tesame met mielie dieetinnames van die Suid-Afrikaanse populasie. Alhoewel, die droëmaalproses van mielies, insluitende die verwydering van die kiem doeltreffende maniere is om mikotoksienes te verminder, word risiko- en blootstellings evaluering beinvloed deur mielie dieetinnames, geslag en etnieseverbandskap. Hierdie was veral opmerklik gedurende blootstelling aan FB in die dieet van landelike mielie bestaansboer gemeenskappe in die Oos-Kaap van Suid- Afrika en bevestig hoe kwesbaar hierdie populasie is. Spesifieke maksimum toelaatbare vlakke om hierdie gemeenskappe te beskerm val buite die huidige internasionale regulatoriese prosesse en benodig dringende aandag. Met die ingewikkelde aard van kankerontwikkeling in gedagte, sal die integrasie van basiese wetenskappe en voedingsepidemiologie, ‘n belangrik bydrae lewer tot die kennis van die negatiewe eienskappe van FB om toepaslike risiko-evaluerings limiete te kan bepaal.

O projeto avaliou os efeitos da aflatoxina B1 (AFB1) e fumonisina B1 (FB1), isoladas e associadas, sobre a produtividade e a qualidade dos ovos de codornas poedeiras (Coturnix coturnix japonica). Duzentas e oitenta e oito aves, adquiridas com idade de 8 semanas, foram subdivididas em 6 grupos experimentais (48 aves por grupo) e submetidas a 6 tipos de tratamentos, constituídos por rações contendo AFB1 e FB1 nas concentrações: (0 AFB1+0 FB1), (0 AFB1+10 mg/kg FB1), (50 &microg/kg AFB1+0 FB1), (50 µg/kg AFB1+10 mg/kg FB1), (200 µg/kg AFB1+0 FB1), e (200 µg/kg AFB1+10 mg/kg FB1). As aves foram alimentadas durante 140 dias (5 ciclos de 28 dias). Os parâmetros de produtividade foram avaliados semanalmente, através do consumo de ração, peso dos ovos, índice de conversão alimentar e curva de produção. A qualidade dos ovos foi avaliada a cada ciclo de 28 dias, cada ovo produzido nesse dia foi analisado individualmente para a determinação do valor de unidade Haugh, gravidade específica e percentual do peso da casca. Ao final do 5º período experimental, o peso médio dos ovos foi significativamente menor (p < 0,05) nas aves alimentadas com 10 mg FB1/kg, 50 &microg/kg AFB1, 200 µg/kg AFB1 e com o tratamento de associação de 10 mg FB1/kg + 50 µg/kg AFB1. Em relação à produção de ovos, as codornas alimentadas com 10 mg FB1/kg apresentaram uma diminuição significativa (p < 0,05), ao final do 3º, 4º e 5º ciclos. O consumo médio diário de ração foi significativamente menor (p< 0,05) nas aves alimentadas com 10 mg FB1/kg, ao final do 4º e 5º ciclos, enquanto que os níveis de 50 ou 200 µg/kg AFB1 provocaram uma diminuição significativa (p < 0,05), ao final do 5º período experimental. Ao final do 1º, 2º e 5º ciclos, o consumo médio de ração foi significativamente menor (p< 0,05) nas aves tratadas com 10 mg FB1/kg + 50 µg/kg AFB1. Os índices de conversão alimentar e os valores de Unidades Haugh não foram afetados (p > 0,05) pelos tratamentos. A gravidade específica dos ovos foi significativamente menor (p < 0,05) ao final do 5º ciclo, nas aves tratadas com 10 mg FB1/kg + 200 µg/kg AFB1. Observou-se uma diminuição significativa (p < 0,05) na porcentagem do peso de casca, nas aves tratadas com 10 mg FB1/kg ao final do 1º ciclo, entretanto, houve um aumento significativo (p < 0,05) nos tratamentos com 200 µg/kg AFB1 e também com 10 mg/kg FB1 + 50 µg/kg AFB1 ao final do 1º ciclo. Já ao final do 5º ciclo, o aumento na porcentagem de peso de casca (p < 0,05) ocorreu somente nas aves tratadas com 10 mg/kg FB1 + 200 µg/kg AFB1. Os resultados demonstraram que a administração prolongada de FB1 e AFB1, isoladas ou associadas nos níveis utilizados no presente experimento, pode causar prejuízos econômicos aos produtores de ovos de codornas. / This study evaluated the individual and combined effects of aflatoxin B1 (AFB1) and fumonisin B1 (FB1) on egg quality and performance of laying Japanese quail (Coturnix coturnix japonica). Two hundred twenty-eight birds were purchased at 8 week of age and randomly distributed into 6 experimental groups and given rations containing AFB1 and FB1 at the following levels: (0 AFB1+0 FB1), (0 AFB1+10 mg/kg FB1), (50 &microg/kg AFB1+0 FB1), (50 &microg/kg AFB1+10 mg/kg FB1), (200 &microg/kg AFB1+0 FB1), e (200 &microg/kg AFB1+10 mg/kg FB1). The birds were fed for 140 days (5 28-day laying periods). Each treatment consisted of four replicates of twelve quail. Egg production and individual egg weight were checked daily. Feed consumption and feed utilization were determined weekly. Eggs laid in the last day of each 28-day laying period were collected and submitted to individual analysis for specific gravity, Haugh units and percent egg shell. Results showed that average egg weight at the end of the fifth cycle was significantly lower (p < 0,05) for groups fed 10 mg FB1/kg, 50 &microg/kg AFB1, 200 &microg/kg AFB1 and also for the group fed 10 mg FB1/kg + 50 &microg/kg AFB1. Average egg production significantly decreased (p < 0,05) for groups fed 10 mg FB1/kg by the end of the third, fourth and fifth cycles. Feed consumption was significantly lower (p < 0,05) for group exposed to 10 mg FB1/kg, by the end of fourth and fifth cycles, whereas birds fed 50 or 200 &microg/kg AFB1 showed a significant decrease (p < 0,05) on feed consumption, by the end of fifth cycle. Birds exposed to 10 mg FB1/kg + 50 &microg/kg AFB1 also showed lower values (p < 0,05) of feed consumption, by the end of first, second and fifth cycles. Feed utilization and Haugh units were not affected (p > 0,05) by AFB1 and FB1. Average egg specific gravity was significantly lower (p < 0,05) for group fed 10 mg FB1/kg + 200 &microg/kg AFB1, by the end of fifth cycle. Percent egg shell was significantly lower (p < 0,05) for group exposed to 10 mg FB1/kg, by the end of the first cycle, however, birds exposed to 200 &microg/kg AFB1 and also to 10 mg/kg FB1 + 50 &microg/kg AFB1, showed a significantly increase (p < 0,05) of percent egg shell, by the of the first cycle. Percent egg shell was significantly higher (p < 0,05) for group fed 10 mg/kg FB1 + 200 &microg/kg AFB1 , by the end of fifth cycle. The results obtained in the present study showed that the prolonged administration of FB1 and AFB1, singly or combined at the levels checked, may cause economic losses to the quail egg producers.

O presente trabalho teve o objetivo de avaliar os efeitos da fumonisina B1 (FB1) sobre a produtividade e a qualidade dos ovos de codornas em início de postura. Para esse fim, 128 aves de 7 semanas de idade foram aleatoriamente distribuídas em quatro grupos experimentais (32 aves por grupo), tendo sido administrada ração contendo 0 (controle), 10, 50 e 250 mg de FB1/kg, durante 28 dias. Cada tratamento esteve constituído por quatro replicatas de oito codornas. A produção e o peso dos ovos foram avaliados diariamente. O consumo de ração e a conversão alimentar foram mensurados semanalmente. Os ovos produzidos no último dia de cada período de 7 dias foram coletados e submetidos à analise individual de densidade, unidade Haugh e percentual de peso da casca em relação ao peso total do ovo. No vigésimo oitavo dia experimental, foram coletadas amostras de sangue para análise de perfil de função hepática (proteína total, albumina, AST, GGT e ácido úrico) e hemograma. Dezesseis aves de cada tratamento foram sacrificadas por deslocamento cervical, e os fígados, rins e coração foram removidos, pesados e submetidos à análise histopatotológica. Comparado com os grupos controles, as codornas alimentadas com ração contendo concentração >= 50 mg de FB1/kg reduziram (p < 0,05) o consumo de alimentos e apresentaram menor (p < 0,05) ganho de peso. Entretanto, a conversão alimentar foi aumentada (p < 0,05) apenas para as aves que receberam 250 mg de FB1/kg na dieta. A produção média de ovos apresentou-se significativamente menor (p < 0,05) para o grupo exposto a 250 mg de FB1/kg. O peso dos ovos diminui significativamente (p < 0,05) para as aves alimentadas com ração contendo concentração de 250 mg de FB1/kg. As médias de densidade e unidade Haugh não foram afetadas (p > 0,05) pela FB1. O peso das cascas dos ovos diminuiu (p < 0,05) nos grupos que receberam concentração >= 50 mg de FB1/kg na dieta. Entretanto, o percentual de casca não foi afetado pela FB1. Comparados com os grupos controle, os tratamentos que receberam concentração >= 50 mg de FB1/kg na dieta apresentaram maior (p < 0,05) peso relativo de fígado. Os pesos relativos do rim e do coração não foram afetados (p > 0,05) pela FB1. Comparando-se com o controle, as aves que receberam concentração de 250 mg de FB1/kg na dieta apresentaram redução (p < 0,05) da porcentagem do hematócrito. Os demais parâmetros do hemograma avaliados não foram afetados (p > 0,05) pela FB1. Com exceção do número de leucócitos aumentado no tratamento 10 mg de FB1/kg de ração (p < 0,05), os parâmetros do leucograma avaliados não foram afetados pela FB1 (p > 0,05). O valor de AST para o tratamento 250 mg de FB1/kg de ração encontrou-se aumentado (p < 0,05) quando comparado ao controle. Os outros parâmetros de bioquímica sérica avaliados no presente estudo não foram afetados pela FB1 (p > 0,05). Com relação aos achados histopatológicos, não houve diferença entre os tratamentos, em tecido hepático, renal e miocárdio, comparando-se com o grupo controle. Esses resultados sugerem que codornas são sensíveis aos efeitos tóxicos da FB1, em níveis que foram descritos como sendo de ocorrência natural, em condições de campo. Os dados indicaram que a exposição a FB1 em níveis >=50 mg de FB1/kg podem afetar adversamente o desempenho de codornas, o que enfatiza a importância do controle da contaminação por FB1 nas rações de codornas. / A 28-d experiment was conducted to evaluate the effect of fumonisin B1 (FB1) on egg production and egg quality of young laying Japanese quail fed contaminated rations. To this end, 128 7-wk-old birds were randomly distributed into four experimental groups (32 birds per group) and given rations containing 0 (controls), 10, 50 and 250 mg FB1/ kg feed. Each treatment consisted of four replicates of eight quail. Egg production and egg weights were checked daily. Feed consumption and feed use were determinated weekly. Eggs laid in the last day of each 7-d period were collected and subjected to individual analysis for specific gravity, Haugh units and percentage eggshells. On day 28, 12 quail from each treatment (4 replicates of 3 birds each) were bled by cardiac puncture and samples used for serum chemistry analyses (total protein, albumin, AST, GGT, and uric acid). Sixteen quail from each treatment were sacrificed by cervical dislocation, and liver, kidney, and heart were removed, weighed and collected for histopathological examination. Compared with controls, quail fed >= 50 mg FB1/ kg had reduced (p < 0.05) feed intake and lower (p < 0.05) body weight gain. However, feed use was only reduced (p < 0.05) for birds fed 250 mg FB1/ kg. Average egg production was significantly lower (p < 0.05) for group exposed to 250 mg FB1/ kg. Egg weight was significantly decreased (p < 0.05) for birds fed 250 mg FB1/ kg. Average specific gravity and Haugh units were not affected (p > 0.05) by FB1. Eggshell weight was reduced (p < 0.05) for birds fed >= 50 mg FB1/ kg. However, percentage eggshell was not affected by FB1. Compared with controls, quail fed >= 50 mg FB1/ kg had increased (p < 0.05) relative liver weight. Relative kidney weight and relative heart weight were not affected (p > 0.05) by FB1. Compared with controls, birds fed 250 mg FB1/ kg diet had reduced (p < 0.05) hematocrits. FB1 had no effet on hematological values evaluated (p > 0.05) but on hematocrits. Despite the icreased (p < 0.05) on total white blood cell count for quail fed 10 mg FB1/ kg diet, FB1 had no effect on heterophil, lymphocyte and monocyte counts (p > 0.05). Compared with controls, AST concentrations were higher (p < 0.05) in quail fed 250 mg FB1/ kg diet. It was not observed any histopathological change in liver, kidney and heart samples from any treatment group, compared with controls. These results suggest that quail are sensitive to the toxic effects of FB1 at levels that have been reported to occur in feedstuff under field conditions. Data indicated that exposure to FB1 at levels >= 50 mg/ kg could adversely affect quail performance, emphasizing the importance of controlling fumonisin contamination in quail rations.

Made available in DSpace on 2016-04-28T20:17:26Z (GMT). No. of bitstreams: 1 2006- Glenda Ribeiro de Oliveira.pdf: 475801 bytes, checksum: 8ca6884856073fd041daad94f50fca0e (MD5) Previous issue date: 2006-11-24 / The intake of mycotoxin-contamined feeds may lead to nutrient losses and can have adverse effects on animal health and on productivity. The aims of this study were: 1) to determine the mycobiota present in poultry feed samples, obtained from three factories in the region of S?o Jos? do Vale do Rio Preto, RJ, Brazil; 2) to evaluate the natural occurrence of aflatoxin B1 (AFB1), fumonisin B1 (FB1) and zearalenone using the method enzyme linked immunosorbent assay (ELISA) competitive, commercial kits of Beacon Analytical Systems Inc, USA and 3) to verify the data results by the ELISA to AFB1 and FB1 comparing them with the high precision liquid chromatography methodology (HPLC) Fungal counts were similar between all culture media tested (103 CFU.g-1). Penicillium spp. (41,26%) was the most prevalent genus followed by Aspergillus spp. (33,33%) and Fusarium spp. (20,63%). Aflatoxin B1 was found in 66,27% samples examined by ELISA kits and values ranged between 2 and 21&#956;g.kg-1. Fumonisin B1 was found in 97,87% and levels ranged between 0,3 and 9,1&#956;g.g-1, cooccurring with aflatoxin B1 in 66,7% of the samples. Low concentrations of zearalenone were found (<1 &#956;g.g-1) in 77,1% poultry feed samples. Correlation between the ELISA kits (AFB1 and FB1) and the HPLC analysis was obtained. Values were r2= 0,9922 and r2=0,9823, respectively. In general, the highest mycotoxin levels were found during the hottest month of sampling. The present study shows the simultaneous occurrence of two carcinogenic mycotoxins, aflatoxin B1 and fumonisin B1 together with another Fusarium mycotoxin (zearalenone) in feed intended for poultry consumption. Many samples contained AFB1 levels near the maximum permissible and it could affect young animals. A synergistic toxic response is possible in animals under simultaneous exposure. / A ingest?o de ra??es contaminadas por micotoxinas pode acarretar perdas no seu valor nutritivo e causar efeitos adversos ? sa?de animal e ? produtividade. Os objetivos desse estudo foram: 1)estabelecer a freq??ncia e a preval?ncia da micobiota presente em amostras de ra??es de frangos de corte provenientes de tr?s f?bricas em S?o Jos? do Vale do Rio Preto-RJ, 2)verificar a ocorr?ncia natural de aflatoxina B1 (AFB1), fumonisina B1 (FB1) e zearalenona (ZEA), utilizando a t?cnica biol?gica de imunoensaios-ELISA competitivo, com kits comerciais (Beacon Analytical Systems Inc, USA) e 3)verificar os resultados obtidos pelo m?todo de ELISA, comparando-os com a t?cnica de Cromatografia L?quida de Alta Efici?ncia (CLAE) para AFB1 e FB1. A contagem dos prop?gulos f?ngicos foi similar entre todos os meios de cultura testados (103 UFC g-1). Penicillium spp (41,26%) foi o g?nero de maior preval?ncia seguido por Aspergillus spp (33,33%) e Fusarium spp. (20,63%). Aflatoxina B1 foi encontrada em 66,27% das amostras analisadas pelos kits de ELISA,com valores variando entre 2 e 21&#956;g.kg-1. Fumonisina B1 foi encontrada em 97,87% e os valores variaram entre 0,3 e 9,1&#956;g.g-1, co-ocorrendo com aflatoxinaB1 em 66,7% das amostras. Baixas concentra??es de zearalenona foram encontradas (< 1&#956;g.g-1)em 77,1% das amostras de ra??o. Foi obtida correla??o entre os kits de ELISA (AFB1 e FB1) e as an?lises em CLAE, com valores de r2= 0,9922 e 0,9823, respectivamente. Em geral, os maiores n?veis de micotoxinas foram encontrados durante os meses mais quentes do ano. O presente estudo mostra a ocorr?ncia simult?nea de duas micotoxinas carcinog?nicas, AFB1 e FB1, juntamente com outra Fusarium micotoxina (zearalenona) em ra??es destinadas ao consumo de frangos. Algumas amostras apresentaram n?veis de AFB1 pr?ximos ao m?ximo permitido, o que poderia afetar aves jovens. Uma resposta t?xica sin?rgica ? poss?vel em animais sob exposi??o simult?nea.

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