Showing papers by "Ministry of Agriculture published in 2000"

A method for determining fumonisin B1 in corn using immunoaffinity column clean-up and thin layer chromatography/densitometry

Abstract: A method for determining fumonisin B1 (FB1) in corn was developed and the clean-up optimized in order to give an extract suitable for one-dimensional thin layer chromatographic (TLC) analysis. FB1 was extracted with a solution of methanol:water (80:20, v/v), purified through an immunoaffinity column and separated on a C18 reversed phase TLC plate. The FB1 was visualized with 0.1 mol/l sodium tetraborate, 0.40 mg/ml fluorescamine in acetonitrile and 0.01 mol/l boric acid:acetonitrile (2:3, v/v) for fluorescence detection, and quantified by densitometric analysis. Water, acetonitrile:water (1:1 v/v) and acetonitrile:water (4:1 v/v) were evaluated as TLC solvents for running both standards and samples together with derivatization procedures aimed at improving separation, resolution, sensitivity and linearity. The mean recovery for FB1 for spiked samples was found to be 85% and the linear equation of standard calibration curve by densitometric analysis gave an r2 value higher than 0.99. The maximum coefficient of variation for replicate analysis of spiked samples was 19%. The absolute amount of FB1 standard detectable on a TLC plate was 2 ng, giving a detection limit for the method of 0.1 mg/kg. The method has been shown to be robust in the application of FB1 monitoring in corn (214 samples) collected in different regions of the country. FB1 was detected in 99% of these samples in the range of 0.2 to 6 mg/kg.

Mormo em eqüídeos nos Estados de Pernambuco e Alagoas

Abstract: Based on clinical-pathological, epidemiological and serological aspects, as well as by the isolation of Burkholderia mallei, foci of glanders were diagnosed in equids of the "Zona da Mata" in the states of Pernambuco and Alagoas. Clinically there was hyperthermia, noisy respiration, loss of appetite, progressive loss of weight leading to emaciation, nasal congestion and muco-purulent discharge, erosions, ulcers and scars of the nasal mucosa. The size of submaxillary and cervical lymphonodes was increased, which contained abscesses and fistules exudating purulent material. In the skin, accompanying the lymph vessels, there were firm nodules and abscesses which in chronic cases fistulated and ulcerated leaving stellar scars. The histopathology of the nodules at various sites, from the horses as well as from the guinea-pigs used for the Strauss test, showed granulomatous lesions and pyogranulomas. The results of this study showed that glanders in the region was emerging and further sero-epidemiological studies are urgent for the eradication of the disease.

Development of a differential multiplex PCR assay for equine herpesvirus 1 and 4 as a diagnostic tool.

Abstract: Summary In this study, a multiplex polymerase chain reaction (PCR) procedure was developed for differentiation of strains and field isolates of equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4). Specific oligonucleotide primers were combined to amplify the thymidine kinase (TK) gene region of EHV-1 and EHV-4, which would yield fragments of different lengths for each virus in the same amplification reaction. The specificity of the largest PCR amplicon for EHV-4 was confirmed by restriction digestion with HindIII. The multiplex PCR proved to be a fast and sensitive method for typing EHV-1 and EHV-4 isolates and for detection and differentiation of both viruses in field samples in which infectious virus is no longer available. The sensitivity was improved by combining cycling optimization and visualization of PCR products in ethidium bromide and silver-stained acrylamide gels.

Prevalence of equine herpesvirus type 1 latency detected by polymerase chain reaction.

Abstract: In this study, an improved polymerase chain reaction (PCR) was used for detection of DNA of latent EHV-1 strains from several sources. Three pairs of oligonucleotide primers spanning fragments of 333 bp, 226 bp and 268 bp of the thymidine kinase (tk) gene, and one primer pair spanning 225 bp of the glycoprotein C (gC) gene were used in specific amplifications. Primers for EHV-4 PCR were also designed. Restriction digests with TaqI confirmed the identity of tk PCR fragments from EHV-1. The sensitivity to detect PCR products was further improved by visualisation in silver-stained acrylamide gels. PCR assays were applied to 267 samples including pools of tissue, peripheral blood leukocytes (PBL) and nasal swabs of archived, farms and abattoir specimens from a total of 116 animals. The EHV-1 DNA was found in 88% of the analysed samples. The prevalence of the EHV-1 latent or persistent form in adult horses was similar to others reports but found higher than previously described in foetuses and young foals. EHV-4 latency was not detected in the Brazilian studied specimens.

Antibody response in cattle after vaccination with inactivated and attenuated rabies vaccines

Abstract: Despite the absence of current official reports showing the number of cattle infected by rabies, it is estimated that nearly 30,000 bovines are lost each year in Brazil. In order to minimize the important economic losses, control of the disease is achieved by eliminating bat colonies and by herd vaccination. In this study, we compare the antibody response in cattle elicited by vaccination with an attenuated ERA vaccine (AEvac) and an inactivated-adjuvanted PV (IPVvac) vaccine. The antibody titers were appraised by cell-culture neutralization test and ELISA, and the percentage of seropositivity was ascertained for a period of 180 days. IPVvac elicited complete seropositivity rates from day 30 to day 150, and even on day 180, 87% of the sera showed virus-neutralizing antibody titers (VNA) higher than 0.5IU/ml. There were no significant differences between the VNA titers and seropositivity rates obtained with IPVvac in the two methods tested. AEvac, however, elicited significantly lower titers than those observed in the group receiving inactivated vaccine. In addition, the profiles of antirabies IgG antibodies, evaluated by ELISA, and VNA, appraised by cell-culture neutralization test, were slightly different, when both vaccines were compared.

Fumonisin levels in commercial corn products in Buenos Aires, Argentina.

Abstract: Fumonisins B1 (FB1) and B2 (FB2) were determined in 35 samples of corn flour and corn grits destined for human consumption and purchased directly from Buenos Aires food shops and supermarkets from October 1996 to January 1997 and during the month of January 1998. During the first period of sample collecting, 16 out of 19 samples were found to be contaminated. Considering all 19 samples, contamination levels were between not detected and 1860 ng/g FB1, and from not detected to 768 ng/g FB2. During the second period all 16 samples were found to be contaminated with levels ranging from 75 to 4987 ng/g FB1, and from not detected to 1818 ng/g FB2. The levels of FB1 and FB2 in the samples collected during January 1998 were significantly higher than the samples collected during the period from October 1996 to January 1997. No significant difference was found in terms of fumonisin levels between the branded and unbranded samples.

Sorovares de Salmonella em carne de eqüídeos abatidos no nordeste do Brasil

Abstract: In the sixties and seventies there was an extraordinary increase in export of horse meat products to Europe and Japan. This favored an increase in risk of Salmonella outspread through those products to human and animal consumer populations. Thus, from an exporting company dealing with horse meat located in northeastern Brazil (state of Pernambuco), 19,238 fragments of more external muscles, Salmonella was isolated from 666 samples colleted from 433 animals (horses and donkeys). The serotyping of 745 isolates showed 98 serovars pertaining to 14 serogroups, predominantly classified into subspecies I (98.9%). S. Anatum, S. Carrau, S. Saintpaul, S. Agona, and S. Typhimurium were the most frequent serovars isolated. Preliminary data indicate that the primary causes for the presence of Salmonella in the meats probably was contact with feces from slaughtered animals, as well as possible contamination of environments, in view of the absence of human carriers researched in part of the personnel.

Genetic variability among and within races of Heterodera glycines Ichinohe assessed by RAPD markers

Abstract: Heterodera glycines Ichinohe, the soybean cyst nematode (SCN) was detected in Brazil in 1992 and since then it has been causing losses to Brazilian soybean crop yields. SCN populations have great genetic diversity which makes it difficult to manage this disease. The objectives of this research were to investigate the genetic variation of 16 SCN populations sampled in middle western and southeastern Brazil, utilizing random amplified polymorphic DNA (RAPD) techniques, and to establish useful and specific RAPD markers for SCN race 3. RAPD markers demonstrated genetic variability among and within SCN populations, and they could be used for monitoring nematode population dynamics. The OPA-07 primer was a reliable molecular marker for race 3, while electrophoretic profile analysis of DNA fragments amplified with OPA-10 primer detected slight variation within those populations identified as race 3. The SCN population from Chapadao do Ceu, GO - sample 2 - was the most genetically distant from the other populations.

Detection of equine herpesvirus 1 DNA in a single embryo and in horse semen by polymerase chain reaction

Abstract: The genome of one equine embryo and three equine semen specimens collected from a Brazilian farm were tested by polymerase chain reaction (PCR) for the presence of EHV-1 and EHV-4-specific timidine kinase (TK) sequences. The PCR detected specific EHV-1 TK gene sequences in all samples tested. The peripheral blood leukocytes (PBL) of the embryo donor mare also was amplified by EHV-1 TK primers. Infectious virus was not recovered from any specimens. The animals did not show any clinical signal of EHV-1 or EHV-4 infections. EHV-4 was not detected in the studied specimens. The results indicate that PCR was more sensitive than virus isolation in cell culture for detecting EHV-1 in semen of carrier horses.

Use of an ELISA system for detection of equine herpesvirus 1 (EHV-1) antibodies in non-symptomatic pregnant mares and neonatal foals

Abstract: An ELISA system was applied to study the prevalence of EHV-1 in vaccinated and non-vaccinated Brazilian horses. Serum samples were taken from non-symptomatic pregnant mares, before and after the parturition, and from their neonatal foals. The antigen was prepared from a purified virus fraction (HVE-1 AB1 strain). The ELISA absorbance of 0.3516 was determined as the threshold of negative values. This cut-off level was defined from a selected interval, which determined a sensibility of 100% and a specificity of 94.7%, from a serum collection obtained from pregnant mares and fetuses. In this study, a strong correlation was found between the ELISA and serum neutralization for specific EHV-1 antibody detection.

Water stress effect and use of granulated products in coffee crop irrigated by the drip system.

Abstract: In order to study the vegetative and produtive development of irrigated coffee of the 'Mundo Novo' variety, an experiment in Planaltina de Goias, GO was installed. Different periods of water deficit and application of different granulated products were compared. Crop evaluation performed for 3 harvests (1995, 1996 and 1997) showed that irrigated plants (with no water deficit) produced 100% more than those without irrigation. As for soil granulate, triadimenol + dissulfoton showed a 20 to 25% increase in production regardless of irrigation.

Influência da aplicação de gesso na produção de matéria seca, na relação nitrogênio: enxofre e concentrações de enxofre, cobre, nitrogênio e nitrato em pastagens de Brachiaria decumbens Stapf

Abstract: Em solo classificado como latossolo vermelho-amarelo, de pH igual a 5,2, foram estudados o efeito da adicao crescente do gesso agricola (CaSO4.2H2O) nos niveis de 0 t/ha (T); 0,5 t/ha (TA); 1,0 t/ha (TB) e 1,5 t/ha (TC), combinados com a aplicacao de 20kg/ha de nitrogenio sob a forma de ureia mais 80kg de K2O/ha sob a forma de cloreto de potassio, sobre a producao de materia seca (MS) da Brachiaria decumbens Stapf, no periodo de janeiro a dezembro. O delineamento experimental foi o de blocos ao acaso, com quatro repeticoes. Foram realizados tres cortes (apos 77, 133 e 341 dias do inicio do experimento) para determinar a producao de materia seca/ha e as concentracoes de enxofre (S), nitrogenio (N), cobre (Cu) e nitrato na forrageira. Observou-se que a producao de MS foi influenciada pelos tratamentos e epoca de corte da forrageira. Porem, nao houve aumento significativo na producao de MS para niveis de adubacao acima de 0,5 t/ha. As concentracoes de S, N, Cu e nitrato nao foram influenciadas pelos tratamentos.

Níveis decrescentes de proteína em dietas suplementadas com complexo enzimático, para coelhos em crescimento. 2. Parâmetros digestivos e composição química do conteúdo cecal

Abstract: The effects of decreasing levels of crude protein (CP) and enzymatic supplementation on digestive traits and caecal content composition of growing rabbits were studied. In a completely randomized design 54 weaned New Zealand White rabbits were divided in four groups of 11 rabbits each and one group of 10 rabbits. The treatment groups fed on diets with 17, 16, 15 or 14% of CP supplemented with 0.05% of enzymatic complex (Vegproâ) with cellulase and protease activities. The control group fed a diet with 17% of CP without the enzymatic complex. The weigth of the full digestive tract, full and empty caecum, and caecum content were affected (P<0.05) by the CP level of the diet. Organic matter percentage, ammonia nitrogen percentage, and molar proportion of acetic and propionic acid in the caecum content were affected by CP level of the diet (P<0.05). The redution of CP level of the diet up to 14% did not show negative effects on evaluated traits.

Níveis decrescentes de proteína em dietas suplementadas com complexo enzimático para coelhos em crescimento. 1. Desempenho produtivo

Abstract: The effects of decreasing levels of crude protein (CP) and enzymatic supplementation on production performance of growing rabbits were studied. In a completely randomized design 54 weaned New Zealand White rabbits were divided in four groups of 11 rabbits each and one group of 10 rabbits. The treatment groups fed on diets with 17, 16, 15 or 14% of CP supplemented with 0.05% of enzymatic complex (VEGPROO ) with cellulase and protease activities. The control group received a diet with 17% of CP without the enzymatic complex. The animals fed 14 and 15% CP diets showed better growth performance with a significant effect of the protein level (P<0.05) of the diet on final body weight, final metabolic body weight, daily weight gain, daily feed intake, daily CP intake, and feed conversion. The reduction of CP level of the diet up to 14%, supplemented with enzymatic complex, and corrected to essential aminoacids levels, did not show negative effects on the evaluated traits.

Recent Developments in Brazilian Coffee Quality: New Processing Systems, Beverage Characteristics and Consumer Preferences

Abstract: Coffee cultivation in Brazil showed remarkable transformations during the sixties, due to the introduction of new varieties developed by the Genetic Section of the Agronomic Institute of Campinas (IAC), to the generalized use of mineral fertilization, to the renovation of old plantations in some traditional regions and to the financial and technical support given by the Brazilian Coffee Institute (IBC). Although the greatest attention was given to plant productivity, the recommendations with respect to quality led to better harvesting practices, to the separation of fermented beans in contact with the soil, and to the use of a wet-processing system in regions showing beverage problems (Silva & Cortez, 1998).

Spermathecal capsule of Eumolpinae (Coleoptera: Chrysomelidae) associated with Theobroma cacao L. (Sterculiaceae) of South Bahia, Brazil

Abstract: Este estudo descreve a forma e as dimensoes da capsula da espermateca em Antytipona epiphania, Bechyne, 1955, Antytipona sp., Cayetunya sp., Colaspis aenea (Fabricius, 1801), Colaspis calcalifera (Bechyne, 1954), Coytiera (Campylochira) pertusa (Lefevre, 1884), Hermesilla sp., Hylax bahiensis Bechyne, 1950, Leprocolapis adducta (Clavaereau, 1914),Leprocolapis sulcata Lefevre, 1877, Nycterodina (Nycterodinella) immetalllica Bechyne & Bechyne, 1961,Percolaspis ornata, (Germar, 1824), Plaumannita sp., Podoxenus sp. e Taimbezinhia theobromae (Bryant, 1924) com o objetivo de auxiliar na identificacao das especies associadas as plantacoes de Theobroma cacao L. na Bahia.

Desempenho de coelhos em crescimento recebendo dietas com suplementação enzimática

Abstract: The objective of this work was to evaluate the weight gain, feed intake, feed conversion, carcass weight and carcass yield of rabbits fed on diets supplemented with increasing levels of an enzyme complex (Vegproâ) of protease and cellulase activities. Seventy-five New Zealand White rabbits were weaned by 40 days of age, being separated at random into 5 treatments, according to the level of enzyme supplementation: A-0.,00; B-0.05; C-0.10; D-0.15 and 0.20%. No significant difference (P<0.05) was observed among treatments for feed intake and daily gain. For feed conversion the only significant (P<0,05) difference was between control and treatment B. Carcass weight were significantly (P<0.05) heavier for animal under diet B (0.05% enzimatic complex) whereas carcass yield did not experience any enzimatic effect.