RESUMEN
A survey was conducted on Guyana's main staple foods, rice, cassava meal and cassava bread to determine the presence and concentration of aflatoxins (AFs) using enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC) with fluorescence detection for concurrence. Aflatoxins are secondary metabolites of the fungus Aspergillus and can be a health risk to humans and animals. Results were compared with European Union Commission (EUC) maximum levels of total aflatoxins of 10 µg/kg. Various types of rice (paddy, steamed paddy, cargo rice, white rice and parboiled rice) were randomly collected either directly from the field and rice mills in Guyana during the November 2015/March 2016 season. Of the total 186 composite samples of rice fractions collected from field and mills, 10% (19) had AF concentrations greater than the maximum EUC level of 10 µg/kg. Fifteen samples had aflatoxin concentrations ranging from 10 to 171 µg/kg, mean 54.4 µg/kg; four samples were outliers. Since Guyanese consume mainly white and parboiled rice, composite samples were taken along the marketing chain at points of sale to determine the presence of AFs. Of the sixty samples of white rice collected, 6.7% (4) had AF concentrations greater than the EUC regulatory limits ranging from 31.9 to 131 µg/kg, mean 80.8 µg/kg. For the 57 samples of parboiled rice, 3.5% (2) samples exceeded the limit with values of 72.6 and 407 µg/kg. Forty (40) samples each of cassava meal and cassava bread were analysed fresh and after 2 months of storage, and no sample exceeded the ELISA detection limit of 0.5 µg/kg.
Asunto(s)
Aflatoxinas/análisis , Contaminación de Alimentos/análisis , Manihot , Oryza , Pan/análisis , Cromatografía Líquida de Alta Presión , Ambiente , Ensayo de Inmunoadsorción Enzimática , Guyana , Límite de Detección , Estaciones del AñoRESUMEN
Exposure to ochratoxin A (OTA) can lead to changes in global gene expression. This study investigated the individual expression of genes turned on and off in renal cells of chicks after different durations of exposure to dietary OTA. One hundred and eighty day-old male broiler chicks (Ross 308) were randomly assigned to a 3 × 3 factorial arrangement of treatments (3 levels of OTA: 0, 1 and 2 mg OTA/kg diet and 3 time periods: 7, 14 and 21 d). Birds were allocated to 36 pens (4 replicate pens of 5 birds each per treatment). For RNA-Sequencing analysis (RNA-Seq), kidney samples were collected weekly from 3 controls and 3 chicks fed 1 mg OTA/kg. Birds fed 2 mg OTA/kg diet were not chosen for analysis because their reduced feed intake could affect gene expression. The libraries were constructed by Illumina's TruSeq RNA protocol. NextGENe software was used for alignment and transcript quantification. Reads per kilobase of target per million tiled reads (RPKM) were used in the Binary test analysis (P < 0.05). The highest RPKM values were used as criterion for the selection of the genes described. A total of 27,638,976 50-bp RNA-Seq reads were produced over the 3 time periods. Transcripts (40,782) were assembled de novo and annotated by homology to either G. gallus or H. sapiens. The genes activated at 7 d were IL9 and TULP1, at 14 d was GHSR and at 21 d were GRK6 and GAPDH. Unlike all other genes, LOC396365 was activated during all time periods. In contrast, the genes deactivated at 7 d were SPAG4 and LOC100857131, at 14 d were LOC771469, NKX2-1, NKX2-8, FOXO1, MyHC and CLDN18 and at 21 d was XPC. The B-G gene was turned off at 7 and 21 d. All of these genes were involved in kidney toxicity. Therefore, the turning on and off responses of these genes may contribute to carcinogenic and tumorigenic effects of OTA in birds.
Asunto(s)
Pollos , Expresión Génica/efectos de los fármacos , Riñón/efectos de los fármacos , Micotoxicosis/veterinaria , Ocratoxinas/toxicidad , Enfermedades de las Aves de Corral/inducido químicamente , Alimentación Animal , Animales , Riñón/patología , Neoplasias Renales/genética , Masculino , Micotoxicosis/patología , Enfermedades de las Aves de Corral/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Análisis de Secuencia de ARNRESUMEN
The individual and combined effects of dietary aflatoxin B(1 )(AFB(1)) and fumonisin B(1) (FB(1)) on liver pathology, serum levels of aspartate amino-transferase (AST) and plasma total protein (TP) of broilers were evaluated from 8 to 41 days of age. Dietary treatments included a 3 × 3 factorial arrangement with three levels of AFB(1 )(0, 50 and 200 µg AFB(1)/kg), and three levels of FB(1 )(0, 50 and 200 mg FB(1)/kg). At 33 days post feeding, with the exception of birds fed 50 mg FB(1 )only, concentrations of AST were higher (p < 0.05) in all other treatment groups when compared with controls. Plasma TP was lower (p < 0.05) at six days post feeding in groups fed 200 µg AFB(1)/kg alone or in combination with FB(1). At day 33 days post feeding, with the exception of birds fed the highest combination of AFB(1 )and FB(1 )which had higher plasma TP than control birds(, )plasma TP of birds fed other dietary treatments were similar to controls. Broilers receiving the highest levels of AFB(1) and FB(1) had bile duct proliferation and trabecular disorder in liver samples. AFB(1) singly or in combination with FB at the levels studied, caused liver damage and an increase in serum levels of AST.
Asunto(s)
Aflatoxina B1/toxicidad , Fumonisinas/toxicidad , Micotoxinas/toxicidad , Alanina Transaminasa/sangre , Animales , Proteínas Sanguíneas/análisis , Pollos , Hígado/efectos de los fármacos , Hígado/patología , MasculinoRESUMEN
A 3-week-feeding study (1-21 d post-hatch) was conducted to evaluate the efficacy of total curcuminoids (TCMN), as an antioxidant, to ameliorate the adverse effects of aflatoxin B1 (AFB1) in broiler chickens. Turmeric powder (Curcuma longa L.) that contained 2.55 % TCMN was used as a source of TCMN. Six cage replicates of five chicks each were assigned to each of six dietary treatments, which included: basal diet; basal diet supplemented with 444 mg/kg TCMN; basal diet supplemented with 1.0 mg/kg AFB1; basal diet supplemented with 74 mg/kg TCMN and 1.0 mg/kg AFB1; basal diet supplemented with 222 mg/kg TCMN and 1.0 mg/kg AFB1; basal diet supplemented with 444 mg/kg TCMN and 1.0 mg/kg AFB1. The addition of 74 and 222 mg/kg TCMN to the AFB1 diet significantly (P < 0.05) improved weight gain and feed efficiency. Increase (P < 0.05) in relative liver weight in birds fed AFB1 was significantly reduced (P < 0.05) with the addition of 74, 222 and 444 mg/kg TCMN to the AFB1 diet. The inclusion of 222 mg/kg TCMN ameliorated the adverse effects of AFB1 on serum chemistry in terms of total protein, albumin and gamma-glutamyl transferase activity. The decreased antioxidant functions due to AFB1 were also alleviated by the inclusion of 222 mg/kg TCMN. It is concluded that the addition of 222 mg/kg TCMN to the 1.0 mg/kg AFB1 diet demonstrated maximum antioxidant activity against AFB1.
Asunto(s)
Aflatoxina B1/toxicidad , Antioxidantes/farmacología , Pollos/crecimiento & desarrollo , Contaminación de Alimentos/análisis , Extractos Vegetales/farmacología , Venenos/toxicidad , Aflatoxina B1/antagonistas & inhibidores , Animales , Antídotos/farmacología , Antioxidantes/metabolismo , Pollos/metabolismo , Curcuma , Curcumina/farmacología , Dieta , Suplementos Dietéticos , Ingestión de Alimentos/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Aumento de Peso/efectos de los fármacosRESUMEN
Adsorption of aflatoxin B(1) (AFB1) by natural montmorillonite (MONT) and montmorillonite modified with copper ions (Cu-MONT) was investigated. Both MONTs were characterized using the X-ray powder diffraction (XRPD) analysis, thermal analysis (DTA/TGA) and scanning electron miscroscopy/electron dispersive spectroscopy (SEM/EDS). The results of XRPD and SEM/EDS analyses of Cu-MONT suggested partial ion exchange of native inorganic cations in MONT with copper occurred. Investigation of AFB1 adsorption by MONT and Cu-MONT, at pH 3, 7 or 9, showed that adsorption of this toxin by both MONTs was high (over 93%). Since AFB1 is nonionizable, no differences in AFB1 adsorption by both MONTs, at different pHs, were observed, as expected. Futhermore, it was determined that adsorption of AFB1 by both MONTs followed a non-linear (Langmuir) type of isotherm, at pH 3. The calculated maximum adsorbed amounts of AFB1 by MONT (40.982mg/g) and Cu-MONT (66.225mg/g), derived from Langmuir plots of isotherms, indicate that Cu-MONT was much effective in adsorbing AFB1. Since, the main cation in an exchangeable position in MONT is calcium, and in Cu-MONT both calcium and copper, the fact that ion exchange of inorganic cations in MONT with copper increases adsorption of AFB1 suggests that additional interactions between AFB1 and copper ions in Cu-MONT caused greater adsorption.
Asunto(s)
Aflatoxina B1/química , Aflatoxina B1/metabolismo , Bentonita/química , Bentonita/metabolismo , Cobre/química , Adsorción , Calcio/metabolismo , Cobre/metabolismo , Difracción de Rayos XRESUMEN
A study was conducted to evaluate the individual and combined effects of ochratoxin A (OA) and Salmonella enterica serovar Gallinarum (S. Gallinarum) on gross and histopathological changes in broiler chickens. One hundred and seventy-six 1-day-old broiler chicks were divided into two groups of 88 chicks each; one group was fed a control mash diet, and the other group was fed a mash diet containing 2 parts/10(6) OA. On day 14, each group was further subdivided into two groups, with one group inoculated with S. Gallinarum intraperitoneally (1.25 x 10(10) colony-forming units/0.5 ml) whereas the other group was not inoculated with S. Gallinarum. Four birds from each group were sacrificed on 1, 2, 3, 5, 7, 10, 14 and 21 days post inoculation to record pathological changes in different organs. Gross and microscopic changes in OA-fed birds indicated the kidneys and bursa of Fabricius as the primary organs to be affected by this toxin. Gross and microscopic changes due to S. Gallinarum infection indicated the liver and spleen as the primary organs affected by this infection. The effects of OA on the kidney and bursa of Fabricius were enhanced following S. Gallinarum infection. Degenerative changes and interstitial nephritis in the kidneys, and lymphocyte depletion from bursal follicles were more pronounced and were observed earlier in the combination group. In conclusion, data indicate that birds fed OA and infected with S. Gallinarum will demonstrate increased pathology compared with birds fed OA alone or those infected with S. Gallinarum but not fed OA.
Asunto(s)
Pollos , Ocratoxinas/toxicidad , Enfermedades de las Aves de Corral/patología , Salmonelosis Animal/patología , Salmonella enterica/patogenicidad , Alimentación Animal , Animales , Riñón/patología , Hígado/patología , Pulmón/patología , Bazo/patología , Timo/patologíaRESUMEN
The validity of a simplified in vitro test tube (TT) method was compared with a more complicated dialysis tubing (DT) method to estimate the percentage of available phosphorus (P) in 41 plant origin and five animal origin feed ingredients for swine. The TT method using 1.0 or 0.25 g samples was compared with the DT method using 1.0 g samples at two pancreatic incubation times (2 vs 4 h) in a 3 x 2 factorial arrangement of treatments. Each DT and TT method treatment was replicated three and six times, respectively. Both methods utilize three enzymatic digestions: (i) predigestion with endoxylanase and beta-glucanase for 1 h, (ii) pepsin digestion for 2 h, and (iii) pancreatin digestion for 2 or 4 h. For the TT method, the entire procedure was conducted in a 50 mL conical centrifuge tube and replicated six times. For the DT method, the first two digestions were conducted in a 10 mL plastic syringe before the contents were quantitatively transferred into a segment of DT for the pancreatic digestion. The percentages of hydrolyzed P for plant origin ingredients measured by the DT method using 1.0 g samples and the TT method using 0.25 g samples were highly correlated (r = 0.94-0.97, P < 0.001) with each other and with published in vivo available P values for swine. Repeatabilities for these two methods ranged from 99.64 to 99.86%. The TT method using 1.0 g samples, however, did not provide valid estimates of P availability for all ingredients. For animal origin ingredients, neither method was significantly correlated (r = 0.1-0.6, P >or = 0.4) with published in vivo available P values. In conclusion, the accuracy and validity of the TT method using 0.25 g samples with a 2 h pancreatic digestion time was equal to or superior to the DT method using 1.0 g samples with a 4 h pancreatic digestion time for estimating P availability in plant origin feed ingredients.
Asunto(s)
Alimentación Animal/análisis , Diálisis/instrumentación , Análisis de los Alimentos/métodos , Fósforo Dietético/farmacocinética , Porcinos , Animales , Disponibilidad Biológica , Digestión , Concentración de Iones de Hidrógeno , Hidrólisis , Fósforo/análisis , Fósforo Dietético/administración & dosificación , Ácido Fítico/análisis , Reproducibilidad de los ResultadosRESUMEN
A study was conducted to evaluate the effects of ochratoxin A (OA) on Escherichia coli-challenged broiler chickens. One hundred and eighty-four one-day-old broiler chicks were divided into two groups of 92 chicks each, with one group fed a control mash diet and the other fed a mash diet containing 2 parts/10(6) OA. On day 14, each group was further subdivided into two groups with one group inoculated with E. coli O78 (1 x 10(7) colony-forming units/0.5 ml) by the intraperitoneal route, whereas the other group was not inoculated with E. coli. Four birds from each group were sacrificed at 1, 2, 3, 5, 7, 10, 14 and 21 days post-inoculation to record pathological changes in the liver, kidneys, heart, lungs, bursa, spleen and thymus. E. coli infection induced perihepatitis and pericarditis in the liver and heart, respectively, in chickens infected with E. coli alone or in OA-fed birds from 1 day post-infection (DPI) onwards. At 1 DPI, a thin fibrin layer covered the liver and heart; however, at subsequent days, the layer became thicker. E. coli infection did not produce appreciable changes in the kidneys, bursa or thymus. However, there was congestion of the lungs along with mononuclear cell infiltration. Ochratoxin feeding induced changes from 10 DPI onwards in chicks fed OA alone and those infected with E. coli. The changes in kidneys included swollen proximal convoluted tubules, degeneration of tubular epithelium and interstitial nephritis. Degenerative changes and mononuclear cell infiltration were recorded in the liver. There was atrophy of the lymphoid organs along with depletion of lymphocytes. Gross and histopathological changes were more severe in chickens fed OA and inoculated with E. coli than the chickens fed OA alone or those infected with E. coli, indicating combined action of these two.
Asunto(s)
Infecciones por Escherichia coli/veterinaria , Ocratoxinas/toxicidad , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/patología , Alimentación Animal/toxicidad , Animales , Bolsa de Fabricio/efectos de los fármacos , Bolsa de Fabricio/patología , Pollos , Infecciones por Escherichia coli/patología , Corazón/microbiología , Técnicas Histológicas , India , Riñón/efectos de los fármacos , Riñón/patología , Hígado/efectos de los fármacos , Hígado/microbiología , Hígado/patología , Pulmón/patología , Bazo/patología , Timo/efectos de los fármacos , Timo/patología , Factores de TiempoRESUMEN
A simplified in vitro test tube (TT) method was developed to estimate the percentage of available P in feed ingredients for swine. The entire digestion procedure with the TT method consists of three consecutive enzymatic digestions carried out in a 50-mL conical test tube: (1) Pre-digestion with endo-xylanase and beta-glucanase for 1 h, (2) peptic digestion for 2 h, and (3) pancreatic digestion for 2 or 4 h. The TT method is simpler and much easier to perform compared to the dialysis tubing (DT) method, because dialysis tubing is not used. Reducing sample size from 1.0 to 0.25 g for the TT method improved results. In conclusion, the accuracy and validity of the TT method is equal to that of our more complicated DT method (r = 0.97, P < 0.001), designed to mimic the digestive system of swine, for estimating the availability of P in plant-origin feed ingredients.