Utilização de um monitor de vídeo como fonte de alta tensão para eletroforese capilar

This article describes the use of a conventional CRT monitor as a high voltage power supply for capillary electrophoresis. With this monitor, a 23-kV high voltage with a ripple of 1.32% was observed. The reproducibility of the applied high voltage was evaluated by measuring the standard deviations of peak area and migration time for five consecutive injections of a test mixture containing potassium, sodium, and lithium cations at 50 mmol L-1. The errors were about 2.5% and 0.6% for peak area and migration time, respectively. The maximum current tested was about 180 mA, which covers most capillary electrophoresis applications. This system has been successfully used for several months, maintaining the desired level of performance.

Métodos de extração e qualidade da fração lipídica de matérias-primas de origem vegetal e animal

Methodologies of extraction of lipids from chicken breast and oats flakes were evaluated: Soxhlet, Folch et al., Bligh & Dyer and Hara & Radin. For chicken breast, the methods Soxhlet, Folch et al. and Bligh & Dyer presented the highest yields in total lipids. With oat flakes, the methods Soxhlet and Bligh & Dyer presented higher yields than the Hara & Radin and Folch et al. The Soxhlet method affected the quality of the lipid fraction in both samples. Extracted lipid components were separated by thin layer chromatography, the chloroform-methanol based was more efficient to extract the neutral and polar lipids.

Aspectos analíticos e regulatórios na determinação de resíduos de macrolídeos em alimentos de origem animal por cromatografia líquida associada à espectrometria de massas

This is an overview of LC-MS techniques applied for macrolide determination in food, including sample preparation and method validation, as well as the policies adopted by international agencies regarding their presence in food. Techniques for the analysis of macrolides in food normally include solid phase or liquid-liquid extraction followed by HPLC. UHPLC presents advantages in running time, detectability and solvent consumption. Triple-quadrupoles are the most common analyzers in instruments used for the determination of contaminants in food, but time-of-flight and ion-trap spectrometers have been successfully applied for analyses focusing on the investigation of structural formula or the presence of degradation products.

O estado da arte na determinação de resíduos de medicamentos veterinários em alimentos de origem animal empregando técnicas cromatográficas acopladas à espectrometria de massas

The determination of veterinary drug residues in foods of animal origin is an important issue because of the risk these compounds pose to human health in addition to their persistence and tendency to bioaccumulate. In recent years, significant progress has been made in the area and this review presents the state of the art in sample preparation procedures associated with chromatographic techniques coupled to mass spectrometry for multiresidue determination of veterinary drugs in food of animal origin at concentration levels suitable for the control of residues and contaminants in food.

OMNIS HOMO DE NECESSITATE EST ANIMAL: SIGNIFICACIÓN Y REFERENCIA VACÍA EN LA SEGUNDA MITAD DEL SIGLO 13

A questão "se uma elocução (palavra/termo/nome) perde seu significado com a destruição das coisas (quer dizer, as coisas significadas)"surge como uma questão sobre o valor-verdade de declarações com um termo vazio como sujeito, a saber, como um subproblema do sofisma "Se 'omnis homo de necessitate est animal' é verdade quando não há homem algum (=OHNEA)". Neste trabalho, trarei as discussões conforme elas se apresentam em "De signis" IV.2 de Roger Bacon, em "Quaestiones logicales", q. 2–3 de Peter John Olivi, no OHNEA de Boethius of Dacia, e no OHNEA de Anonymus Alani. Tais textos nos apresentam quatro modos diversos de nos relacionarmos com a questão sobre significação para OHNEA e, assim, com quatro posições diferentes sobre a relação entre significação e referência vazia. Usarei Anonymus Alani como o fio conductor de minha análise, inserindo outras posições onde tal se fizer relevante.

Zoneamento bioclimático da região sudeste do Brasil para o conforto térmico animal e humano

O objetivo deste trabalho foi avaliar as condições de clima da região Sudeste do Brasil, por meio do índice de temperatura e umidade (ITU), e apresentar o zoneamento bioclimático relacionado ao conforto térmico animal e humano. Os valores de ITU foram estimados a partir de dados de temperatura e umidade relativa do ar para o período de 1980 a 2000. Quatro intervalos de ITU foram usados para classificar o desempenho humano (ITU < 74: conforto; 74 < ITU < 79: quente; 79 < ITU < 84: muito quente, e ITU > 84: extremamente quente), e dois intervalos para classificar a produção animal (79 < ITU < 84: perigoso e ITU > 84: emergência). Os resultados mostraram maior risco de desconforto térmico no período de outubro a abril, comparado ao período entre maio e setembro. O período mais crítico ocorreu entre dezembro e março. Apesar de se ter observado que valores de ITUméd entre 79 e 84 ocorreram em menos de 3,6% do tempo, humanos, bem como animais, podem sofrer algum grau de estresse térmico durante as horas mais quentes do dia, afetando ambos negativamente, produção animal e rendimento humano. Valores de ITU maiores que 84 não foram observados para a região estudada.

Influência da distância entre passadas de colhedora equipada com monitor de colheita na precisão dos mapas de produtividade na cultura do milho

Um dos entraves para a maior expansão da agricultura de precisão está, principalmente, no elevado custo dos equipamentos a serem utilizados. A geração de mapas de produtividade é a fase de mais fácil execução na agricultura de precisão. Entretanto, quando várias colhedoras operam simultaneamente em uma determinada área, nem sempre é possível dispor de monitores de colheita em todas as máquinas. Assim, neste trabalho, foi avaliado o decréscimo da precisão em mapas de produtividade obtidos a partir de áreas onde se utilizaram colhedoras não-equipadas com monitor de colheita associadas a colhedoras monitoradas. Também foram comparados os métodos de interpolação "inverso da distância ao quadrado" e "krigagem". Inicialmente, a interpolação do mapa com todos os pontos de amostragem (original) foi gerada e, a partir dessa, foi feita a eliminação de passadas de modo a obter os mapas simulados. Na comparação entre os mapas simulados e o original, foi utilizado o coeficiente de desvio relativo - CDR, e o índice kappa. O número de passadas eliminadas diminuiu a precisão dos mapas em ambos os métodos de interpolação. Sendo assim, a quantidade mínima necessária de monitores em um conjunto de colhedoras depende da precisão desejada. Portanto, as máquinas devem ser intercaladas de maneira que as amostras sejam coletadas uniformemente por toda a área a ser colhida.

Logistic regression to estimate the welfare of broiler breeders in relation to environmental and behavioral variables

The increasing demand of consumer markets for the welfare of birds in poultry house has motivated many scientific researches to monitor and classify the welfare according to the production environment. Given the complexity between the birds and the environment of the aviary, the correct interpretation of the conduct becomes an important way to estimate the welfare of these birds. This study obtained multiple logistic regression models with capacity of estimating the welfare of broiler breeders in relation to the environment of the aviaries and behaviors expressed by the birds. In the experiment, were observed several behaviors expressed by breeders housed in a climatic chamber under controlled temperatures and three different ammonia concentrations from the air monitored daily. From the analysis of the data it was obtained two logistic regression models, of which the first model uses a value of ammonia concentration measured by unit and the second model uses a binary value to classify the ammonia concentration that is assigned by a person through his olfactory perception. The analysis showed that both models classified the broiler breeder's welfare successfully.

Produção animal e o meio ambiente: uma comparação entre potencial de emissão de metano dos dejetos e a quantidade de alimento produzido

O objetivo do trabalho foi efetuar a comparação das principais espécies de interesse agropecuário, em relação à eficiência de conversão das dietas em produtos de origem animal (carne ou ovo), produção de resíduo e potencial de emissão de metano, a partir da fermentação dos resíduos. Para isso, foram selecionadas cinco espécies de animais durante a fase de produção: 1) suínos, do nascimento ao abate (peso vivo (PV) final de 90 kg) ; 2) bovinos, do desmame ao abate (PV: 520 kg); 3) caprinos, do desmame ao abate (PV: 30 kg); 4) aves, durante toda a fase de postura (14,7 kg de ovos); 5) frango de corte, do nascimento ao abate (PV: 3,1 kg). Para a estimativa dos parâmetros propostos, foram medidos os dados do desempenho e efetuou-se a biodigestão anaeróbia dos dejetos produzidos pelos animais. De maneira geral, os dejetos dos ruminantes apresentaram altas concentrações de fibra e baixos potenciais de produção de biogás; no entanto, o menor desempenho destes animais na conversão do alimento em produto e a maior produção de dejetos fizeram com que eles apresentassem maiores produções de metano por kg de alimento produzido.

Method of numerical correction of errors occasioned by delay of records during the monitoring of environmental variables of interest for animal production

Thermal and air conditions inside animal facilities change during the day due to the influence of the external environment. For statistical and geostatistical analyses to be representative, a large number of points spatially distributed in the facility area must be monitored. This work suggests that the time variation of environmental variables of interest for animal production, monitored within animal facility, can be modeled accurately from discrete-time records. The aim of this study was to develop a numerical method to correct the temporal variations of these environmental variables, transforming the data so that such observations are independent of the time spent during the measurement. The proposed method approached values recorded with time delays to those expected at the exact moment of interest, if the data were measured simultaneously at the moment at all points distributed spatially. The correction model for numerical environmental variables was validated for environmental air temperature parameter, and the values corrected by the method did not differ by Tukey's test at 5% significance of real values recorded by data loggers.

Evaluation of roof slope and exposure with different roofing materials in reduced models of animal production facilities in spring and summer

The present study was conducted at the Department of Rural Engineering and the Department of Animal Morphology and Physiology of FCAV/Unesp, Jaboticabal, SP, Brazil. The objective was to verify the influence of roof slope, exposure and roofing material on the internal temperature of reduced models of animal production facilities. For the development of the research, 48 reduced and dissemble models with dimensions 1.00 × 1.00 × 0.50 m were used. The roof was shed-type, and the models faced to the North or South directions, with 24 models for each side of exposure. Ceramic, galvanized-steel and fibro tiles were used to build the roofs. Slopes varied between 20, 30, 40 and 50% for the ceramic tile and 10, 30, 40 and 50% for the other two. Inside the models, temperature readings were performed at every hour, for 12 months. The results were evaluated in a general linear model in a nested 3 × 4 × 2 factorial arrangement, in which the effects of roofing material and exposure were nested on the factor Slope. Means were compared by the Tukey test at 5% of probability. After analyzing the data, we observed that with the increase in the slope and exposure to the South, there was a drop in the internal temperature within the model at the geographic coordinates of Jaboticabal city (SP/Brazil).

Changes in motor behavior during pregnancy in rats: the basis for a possible animal model of restless legs syndrome

PURPOSE:Pregnant women have a 2-3 fold higher probability of developing restless legs syndrome (RLS – sleep-related movement disorders) than general population. This study aims to evaluate the behavior and locomotion of rats during pregnancy in order to verify if part of these animals exhibit some RLS-like features.METHODS:We used 14 female 80-day-old Wistar rats that weighed between 200 and 250 g. The rats were distributed into control (CTRL) and pregnant (PN) groups. After a baseline evaluation of their behavior and locomotor activity in an open-field environment, the PN group was inducted into pregnancy, and their behavior and locomotor activity were evaluated on days 3, 10 and 19 of pregnancy and in the post-lactation period in parallel with the CTRL group. The serum iron and transferrin levels in the CTRL and PN groups were analyzed in blood collected after euthanasia by decapitation.RESULTS:There were no significant differences in the total ambulation, grooming events, fecal boli or urine pools between the CTRL and PN groups. However, the PN group exhibited fewer rearing events, increased grooming time and reduced immobilization time than the CTRL group (ANOVA, p<0.05).CONCLUSION:These results suggest that pregnant rats show behavioral and locomotor alterations similar to those observed in animal models of RLS, demonstrating to be a possible animal model of this sleep disorder.

Monitoring bovine viral diarrhea virus (BVDV) infection status in dairy herds

This study was designed to assess the relationship between antibodies against bovine viral diarrhea virus (BVDV) determined in the bulk tank milk (BTM) and the within-herd seroprevalence. We also assessed the efficiency of measuring antibody levels in BTM samples to monitor BVDV infection status in a herd. In the 81 farms included in the study, BTM samples were obtained and blood samples withdrawn from all cattle older than one year. The infection status was then determined in serum and milk using a commercial blocking ELISA based on the detection of anti-p80 antibodies. Apart from these baseline serum and milk samples, another BTM sample was collected from each herd 9 months later, and a third BTM sample obtained 9 months after this. In these second and third milk samples, anti-BVDV antibodies were determined using the same ELISA kit. Statistical tests revealed good agreement between herd seroprevalences (% seropositive animals in the herd) and the antibody levels detected in the BTM samples. During the 18 months of follow-up, the farms with persistently infected cattle at the study outset (14.8% of the herds) showed a significant decrease in BTM antibody titers after virus clearance. Conversely, a significant increase in BTM antibody levels was observed in the herds infected with BVDV during the follow-up period. Our findings indicate that monitoring antibody levels in the BTM is a useful method of identifying changes in the BVDV infection status of a herd.