Ednaldo Carvalho Guimarães

Variabilidade espacial de atributos químicos do solo em áreas sob sistema plantio convencional

SUMMARY : SPATIAL VARIABILITY OF SOIL CHEMICAL ATTRIBUTES INAREAS MANAGED UNDER CONVENTIONAL TILLAGE The spatial variability of soil chemical attributes was evaluated in a commercialplantation under conventional soil tillage in Uberlândia, state of Minas Gerais, Brazil, in2004. The sampling grid was the Santa Rosa Farm, where the soil is classified as veryclayey Red Latosol (680 g kg -1 clay). The objective was to evaluate the spatial distributionand dependence of the soil chemical attributes in a plantation under conventional soiltillage. For this purpose, soil data were collected from a grid of 121 sampling points in the0–0.2 m layer, spaced 50 m apart, and analyzed by means of geostatistics. The followingsoil attributes were assessed: soil pH water ; phosphorus and available potassium; calcium,magnesium and exchangeable aluminum; H + Al; boron; copper; iron, manganese; zinc;sulphur and organic matter. The values of base saturation (V %), total CEC (T) and sum ofbases (SB) were also computed. The data were evaluated by descriptive statistics andspatial dependence analysis, through the adjustment of semivariograms. The variationcoefficient (CV) of most attributes was high; the highest one was found for phosphorus(73.51 %) and the lowest for soil pH

Variabilidade espacial do pH, teores de matéria orgânica e micronutrientes em profundidades de amostragem num Latossolo Vermelho sob semeadura direta

The space variability of the indexes of fertility of the soil increases with the no-till system, being verified differences in the nutrients contents of a superficial layer of the soil in relation to the other lower layer. Therefore, it requires the definition of new sampling procedures to contemplate those alterations. The study was aimed at evaluating the spatial variability of the pH, organic matter and micronutrients (B, Cu, Fe, Mn and Zn) in a Acrustox loamy texture, cultivated since 1995 under no till system. The soil was sampled in regular intervals of 50m, in regular mesh of 121 points, in three depths (0-10cm, 10-20cm and 0-20cm). The data evaluated by descriptive statistics and geostatistics, based on semivariograms adjustment. Larger contents of organic matter, Mn and Zn were verified in the first 10cm of the soil, whereas contrary behaviors were observed for Fe. The highest variabilities were found for B and the lowest for pH in water. For the attributes that presented spatial dependence, this was classified as moderate or strong. Most of the data was adjusted to the semivariograms of exponential model, folloed by the spherical model. Only the variable zinc, in the depth of 0-20cm, did not present spatial dependence. The results obtained results should be considered in the definition of plans of soil sampling and management fertilization of the studied area by the analysis of range and horizontal and vertical variability of the chemical attributes evaluated.

Occurrence of Hepatozoon sp. in dogs in the urban area originating from a municipality in southeastern Brazil

The occurrence of Hepatozoon sp. infection in dogs was evaluated in the urban area of Uberlândia, Minas Gerais, Brazil. The study involved 300 animals, 120 from the Veterinary Hospital of the Federal University of Uberlândias Faculty of Veterinary Medicine, 80 from private clinics, and 100 from the Animal Protective Association (APA). Among these animals, 7.66% presented Hepatozoon sp. gamonts inside neutrophils. No statistically significant difference was found among the diagnoses based on capillary and venous blood smears, but a statistical significance was identified in age range and breed. The main signs and symptoms the animals presented were pale mucous membranes, swollen lymph nodes, ocular discharge and pain in response to renal palpation. All the ticks collected were of the species Rhipicephalus sanguineus and no oocyst of the parasite was found in the hemolymph of the ixodidae. The findings of this study reinforce the presence of Hepatozoon sp. infecting dogs in Uberlândia, MG, with age and breed possibly related to the infection. The symptoms presented by the animals were consistent with those reported by other researchers.

Variabilidade temporal da precipitação mensal e anual na estação climatológica de Uberaba-MG

The purpose of this work was to verify the temporal dependence of monthly rainfall in the climatological station of Uberaba-MG, Brazil, using geostatistical methods. It was evaluated the precipitation in series of rainfall monthly data from 1914 to 2000. It were done exploratory and geostatistical analysis. The exploratory analysis was made by calculating basic statistics and histograms and the geostatistical analysis was made by semivariogram. According to the results, a normality tendence was verified in months from october to march. From april to September, it was verified an asymmetric tendence. Semivaviograms showed the nugget effect. As a conclusion, these variables did not present spatial dependence and statistical inferences can be made assuming temporal independence.

Previsão da temperatura média mensal de Uberlândia, MG, com modelos de séries temporais

Modelos de series temporais tem sido amplamente usados no estudo de variaveis climatologicas, como temperatura e precipitacao. Diversos sao os objetivos tracados neste trabalho a fim de se analisar a serie de temperatura media mensal da cidade de Uberlândia, MG, descrevendo seus componentes, e fazer previsoes para periodos subsequentes atraves de modelos ajustados para a serie. A analise permitiu identificar, na serie, a presenca dos componentes, tendencia e sazonalidade. Modelos do tipo SARIMA foram ajustados e, por meio dos criterios AIC (Akaike Information Criterion), BIC (Bayesian Information Criterion) e MSE (Mean Square Error) foi selecionado o modelo SARIMA (3,1,0)(0,1,1) para fins de previsao.

Influência da ordem e estádios da lactação no perfil bioquímico sangüíneo de cabras da raça Saanen

The serum biochemical profile of Saanen dairy goat was investigated with the purpose of analyzing the physiological variations and the influence of lactation order and stage in terms of possible biomarkers to monitor the energetic balance and the metabolic adequacy during lactation. Blood samples were taken from lactating goats at first, second and third lactation. They were collected from the jugular vein in a vacutainer tube with separator gel to obtain sera and to determine protein, metabolite, mineral and enzyme concentrations. The lactation order influence was observed on total protein, glucose, triglycerides, total and ionized calcium, aspartate aminotransferase (AST) and alkaline phosphatase values and the lactation stages on serum concentrations of total proteins, glucose, triglycerides and magnesium, AST and alkaline phosphatase. It was inferred that glucose, triglycerides, total calcium, ionized calcium, magnesium, AST and alkaline phosphatase are effective biomarkers to detect the energetic and mineral imbalance in Saanen dairy goats.

Variabilidade espacial dos teores de macronutrientes em latossolos sob sistema plantio direto

A eficacia dos planos de amostragem do solo pode ser aumentada se for conhecida e considerada a variabilidade espacial de seus atributos, e, para isso, devem ser estudados os fatores que a determinam. O objetivo deste trabalho foi avaliar a variabilidade espacial dos teores de macronutrientes P, K, Ca, Mg e S em dois Latossolos, um muito argiloso e outro de textura media, cultivados com manejo semelhante, ha oito anos sob sistema plantio direto. A coleta das amostras do solo foi realizada em intervalos regulares de 50 m, totalizando 121 pontos, em duas camadas (0-10 e 10-20 cm). Os dados foram avaliados por estatistica descritiva e geoestatistica, com base no ajuste de semivariogramas. Verificou-se que a dependencia espacial varia conforme o elemento, a textura do solo e a profundidade de coleta da amostra. Assim, o Latossolo de textura media, de maneira geral, apresentou maior variabilidade espacial para os teores dos nutrientes em relacao ao de textura muito argilosa. A camada de 0-10 cm, nos dois Latossolos, proporcionou maior variabilidade espacial para os teores dos nutrientes avaliados. A analise de dependencia espacial mostrou que, nos dois solos e nas duas camadas, a maioria dos nutrientes estudados apresentou moderada correlacao espacial. Os modelos de semivariogramas ajustados foram o exponencial e o esferico, sendo o primeiro em maior quantidade. Maiores teores de todos os macronutrientes avaliados foram verificados nos primeiros 10 cm do solo. Os valores de alcance da dependencia espacial foram menores no Latossolo de textura media, variando de 9 a 29 m; no de textura muito argilosa eles variaram de 31 a 399 m. Se for adotada a geoestatistica no esquema de amostragem, o numero de amostras a serem coletadas sera menor no Latossolo de textura muito argilosa, devido aos maiores valores do alcance apresentados por todas as variaveis.

Morfometria da mucosa duodenal em frangos de corte submetidos à temperatura ambiente cíclica elevada

Os efeitos da temperatura ambiente ciclica elevada sobre a morfometria da mucosa duodenal e o peso corporal em frangos de corte foram avaliados. Setenta pintos de corte, machos, foram alojados em gaiolas e distribuidos em dois grupos. Um grupo foi submetido diariamente, durante uma hora, a temperatura ambiente ciclica elevada do primeiro ate o 42o dia de idade (ambiente ST); e outro foi mantido em conforto termico (ambiente TN). Cinco frangos de cada grupo foram sacrificados, semanalmente, por deslocamento cervical para mensuracao da altura de vilosidades (VI), profundidade das criptas (CR) e relacao vilo/cripta (VI/CR) duodenal. Dez aves de cada grupo foram pesadas semanalmente em balanca digital. Utilizou-se delineamento inteiramente ao acaso em esquema fatorial 7x2 (sete idades: um, sete, 14, 21, 28, 35 e 42 dias, e dois ambientes: ST e TN). Os ambientes foram comparados pelo teste de Fisher (P<0,05), e, para avaliar o efeito da idade, foi realizada analise de regressao polinomial. As aves do ambiente ST apresentaram menores VI aos 14 e 21 dias, menor CR aos 28 dias e menor VI/CR aos 21 dias de idade do que as aves do ambiente TN. A temperatura ambiente ciclica elevada teve efeito danoso sobre a estrutura da mucosa duodenal de frangos de corte ate a quarta semana de idade e sobre o peso corporal ao final do ciclo produtivo.

Avaliação do coeficiente de variação como medida da precisão em experimentos com frangos de corte

Coefficients of variation (CV) were taken from several researches published in Brazil, with emphasis on broilers performance and their most studied characteristics, such as weight gain, feed consumption, feed:weight gain ratio, mortality, viability, body weight and yields of carcass, breast, legs, abdominal fat, wings and back. The purpose of the study was to establish CV bands which can guide the evaluation of each variable in future experiments. Based on relations between the median (Md) and pseudosigma (PS), a table was created with suggested intervals for the cited parameters. Larger coefficient of variation intervals were observed for abdominal fat yield. The other variables showed relatively low CV interval bands.

Variabilidade espacial de atributos químicos em diferentes profundidades em um Latossolo em sistema de plantio direto

Spatial variability of chemical attributes at different depths in an Oxisol under no-till system The study of spatial variability of soil chemical attributes is an important step in precision agriculture. The objective of this study was to evaluate the spatial variability at two depths (0-10 and 10-20 cm) of the pH in water, base saturation, and levels of organic matter and micronutrients (B, Cu, Fe, Mn and Zn) in an Oxisol, medium texture, under no-tillage system for eight years. Soil sample collection was performed at regular intervals of 50 m in a regular grid of 121 points. Data were analyzed by descriptive statistics and geostatistics based on the adjustment of semivariograms. Higher levels of organic matter, Zn and Mn were recorded in the first 10 cm of soil. The greatest variability was found for B and the lowest for pH in water. Most of the data fit the model of Gaussian semivariogram. The values of range were different as a function of the sampling depth and greater at the depth 010 cm. If a geostatistical sampling scheme is used, the number of samples to be collected will be different for the two depths and among the evaluated attributes.