ABSTRACT. This study investigated the effects of adding different adsorbent substances to broilers feed naturally contaminated by mycotoxins. Two hundred and eighty male 1-day-old chicks, Cobb Slow® lineage, were distributed in a randomized block design with 4 treatments, 5 repetitions with 14 birds each. The treatments consisted of: T1- basal feed naturally contaminated with mycotoxins. T2- basal feed + Bentonite, Thistle Extract, Yeast Extract, Vitamin E and Choline. T3- basal feed + Bentonite, Thistle Extract, yeast cell wall and Silymarin. T4- basal feed + Bentonite and Algae extract. Performance (weight gain, feed intake, feed conversion) at 7, 14, 21, 28 days were evaluated. At 28 days, a portion of the jejunum was collected in two birds by replicate to study the intestinal morphology. The relative weight of the gizzard, proventricle and total intestine was evaluated. The data obtained were analyzed using the statistical program SAS (9.3). With the use of any adsorbents studied, the performance and liver weight were improved in all evaluated periods. Thus, the inclusion of adsorbents improves the performance of the broiler chickens when the feed is contaminated by mycotoxins.

RESUMO. O objetivo deste trabalho foi avaliar alternativas de armazenagem de milho viáveis a pequenas propriedades rurais em dois experimentos anuais de armazenagem. Um esquema fatorial 4x5 foi utilizado, com quatro tipos de acondicionamentos de armazenagem (sacarias convencionais, bolsas herméticas, silo metálico e espigas) e cinco períodos de tempo (0, 3, 6, 9 e 12 meses). Utilizou-se híbridos de milho (2B688RR, 30K73Hx) cultivados nas safras de inverno 2012 e verão 2012/2013 em Dois Vizinhos, Paraná. Os parâmetros avaliados foram: teor de água, contagem de Aspergillus sp., Fusarium sp. e ocorrência de aflatoxinas (B1, B2, G1 e G2). Os grãos das bolsas herméticas apresentaram o menor teor de água. Verificou-se Aspergillus sp. e Fusarium sp. respectivamente em 20,4 e 86,1% e em 83,3 e 91,6% das amostras do armazenamento safra de inverno e de verão. Não houve influência do acondicionamento e do tempo de armazenagem na ocorrência de Aspergillus sp. e de aflatoxinas no armazenamento safra de inverno. O milho em espigas, do armazenamento safra de verão, apresentou a menor contagem de Aspergillus sp. e não apresentou aflatoxinas. Detectou-se aflatoxinas em níveis de 2,8-14,5 e de 3-197,5 µg kg-1 nos armazenamentos safra de inverno e de verão, respectivamente.

ABSTRACT. The aim of this study was to assess alternatives for viable corn storage for small rural properties in two annual storage experiments. A 4×5 factorial design was used with four types of storage (conventional bags, hermetic bags, metal silos and corncobs) and five periods of storage (0, 3, 6, 9 and 12 months). We used corn hybrids 2B688RR and 30K73Hx cultivated in winter 2012 and summer 2012/2013 in the city of Dois Vizinhos, Paraná, Brazil. The moisture contents, counts of Aspergillus sp. and Fusarium sp., and the occurrence of aflatoxins (B1, B2, G1 and G2) were assessed. The kernels stored in hermetic bags had lower moisture contents. Aspergillus sp. and Fusarium sp. were observed in 20.37 and 86.11% of winter storage samples, respectively, and in 83.3 and 91.6% of summer storage samples, respectively. The storage system and time of storage had no influence on the occurrence of Aspergillus sp. and aflatoxins in the winter crop samples. The corncobs from the summer crop samples had the lowest counts of Aspergillus sp. and did not have aflatoxins. We detected aflatoxins at concentrations of 2.8-14.5 and 3-197.5 µg kg-1 in the winter and summer crop samples, respectively.

O objetivo deste trabalho foi determinar a magnitude dos efeitos diretos e indiretos de parâmetros físico-químicos e microbiológicos sobre a ocorrência de aflatoxinas em grãos de milho armazenados, por meio da análise de trilha. Os dados foram coletados em dois experimentos: um cultivo de inverno (colheita do milho em julho de 2012) e um cultivo de verão (colheita em fevereiro de 2013). Os grãos foram armazenados por 12 meses, em dois tipos de acondicionamentos: em sacarias convencionais de polipropileno e a granel em silo metálico. Avaliaram-se 14 características dos grãos. Calculou-se a matriz de correlações de Pearson entre todos os parâmetros, realizou-se o diagnóstico de multicolinearidade e, posteriormente, aplicou-se a análise de trilha com regressão em crista. Observou-se forte influência das condições ambientais entre as safras de inverno e de verão, e entre época e tipo de armazenagem, nos coeficientes de análise de trilha. As variáveis teor de umidade, conteúdo de cinzas, proteínas, lipídios, grãos sem defeitos, massa volumétrica, incidência de Penicillium sp., Aspergillus sp. e Fusarium sp. devem ser consideradas conjuntamente na definição da possibilidade de ocorrência de aflatoxinas na massa de grãos armazenados.

The objective of this work was to determine the magnitude of the direct and indirect effects of the physicochemical and microbiological parameters on the occurrence of aflatoxins on stored maize kernels, through path analysis. Data were collected in two experiments: one winter crop (maize harvest in July 2012) and one summer crop (harvest in February 2013). Grains were stored for 12 months in two types of packaging: in conventional polypropylene sacks and bulk storage in metallic silo. Fourteen grain characteristics were evaluated. The matrix of Pearson's correlations was calculated between all parameters, the diagnosis of multicollinearity was performed, and subsequently path analysis was applied with ridge regression. A strong influence of environmental conditions was observed between winter and summer crops, and between season and type of storage, in path analysis coefficients. The variables moisture content, ash, proteins, lipids, undamaged kernels, volumetric weight, incidence of Penicillium sp., Aspergillus sp., and Fusarium sp. should be considered together for defining the probability of aflatoxin occurrence in the bulk of stored kernels.