Digital surface area assessment of broiler chickens

Surface area (SA) of poultry is an important parameter for heat and mass transfer calculations. Optical approaches, such as the moiré technique (MT), are non-destructive, result in accuracy and speed gains, and preserve the object integrity. The objective of this research was to develop and validate a new protocol for estimating the surface area (SA) of broiler chickens based on the MT. Sixty-six Ross breed broiler chickens (twenty-seven male, thirty-nine female, ages spanning all growth phases) were used in this study. The dimensions (length, width and height) and body mass of randomly selected broiler chickens were evaluated in the laboratory. Chickens were illuminated by a light source, and grids were projected onto the chickens to allow their shape to be determined and recorded. Next, the skin and feathers of the chickens were removed to allow SA to be determined by conventional means. These measurements were then used for calibration and validation. The MT for image analysis was a reliable means of evaluating the three-dimensional shape and SA of broiler chickens. This technique, which is neither invasive nor destructive, is a good alternative to the conventional destructive methods.

Terrain forms and spatial variability of soil properties in an area cultivatedwith citrus

The technique of precision agriculture and soil-landscape allows delimiting areas for localized management, allowing a localized application of agricultural inputs and thereby may contribute to preservation of natural resources. Therefore, the objective of this work was to characterize the spatial variability of chemical properties and clay content in the context of soil-landscape relationship in a Latosol (Oxisol) under cultivation of citrus. Soil samples were collected at a depth of 0.0-0.2 m in an area of 83.5 ha planted with citrus, as a 50-m intervals grid, with 129 points in concave terrain and 206 points in flat terrain, totaling 335 points. Values for the variables that express the chemical characteristics and clay content of soil properties were analyzed with descriptive statistics and geostatistical modeling of semivariograms for making maps of kriging. The values of range and kriging maps indicated higher variability in the shape of concave topography (top segment) compared with the shape of flat topography (slope and hillside segments below). The identification of different forms of terrain proved to be efficient in understanding the spatial variability of chemical properties and clay content of soil under cultivation of citrus.

Probabilistic structure of an annual extreme rainfall series of a coastal area of the State of São Paulo, Brazil

This study aimed to describe the probabilistic structure of the annual series of extreme daily rainfall (Preabs), available from the weather station of Ubatuba, State of São Paulo, Brazil (1935-2009), by using the general distribution of extreme value (GEV). The autocorrelation function, the Mann-Kendall test, and the wavelet analysis were used in order to evaluate the presence of serial correlations, trends, and periodical components. Considering the results obtained using these three statistical methods, it was possible to assume the hypothesis that this temporal series is free from persistence, trends, and periodicals components. Based on quantitative and qualitative adhesion tests, it was found that the GEV may be used in order to quantify the probabilities of the Preabs data. The best results of GEV were obtained when the parameters of this function were estimated using the method of maximum likelihood. The method of L-moments has also shown satisfactory results.

Management zones definition using soil chemical and physical attributes in a soybean area

Several equipments and methodologies have been developed to make available precision agriculture, especially considering the high cost of its implantation and sampling. An interesting possibility is to define management zones aim at dividing producing areas in smaller management zones that could be treated differently, serving as a source of recommendation and analysis. Thus, this trial used physical and chemical properties of soil and yield aiming at the generation of management zones in order to identify whether they can be used as recommendation and analysis. Management zones were generated by the Fuzzy C-Means algorithm and their evaluation was performed by calculating the reduction of variance and performing means tests. The division of the area into two management zones was considered appropriate for the present distinct averages of most soil properties and yield. The used methodology allowed the generation of management zones that can serve as source of recommendation and soil analysis; despite the relative efficiency has shown a reduced variance for all attributes in divisions in the three sub-regions, the ANOVA did not show significative differences among the management zones.

Deposição de calda na aplicação aérea e terrestre de fitossanitário na cultura da batata

O objetivo deste trabalho foi avaliar a deposição de calda pulverizada na cultura da batata e o espectro de gotas promovidos pela aplicação aérea e terrestre. O experimento foi repetido em duas épocas, em lavouras comerciais de batata, no delineamento inteiramente casualizado, em esquema fatorial 6 x 2, sendo seis formas de aplicação (aérea, a 15 e 30 L ha-1 com atomizador rotativo, e terrestre, a 200 e 400 L ha-1, com pontas de jato plano duplo, com indução de ar e jato cônico vazio); e duas composições de calda (água e água mais o adjuvante fosfatidilcoline + ácido propiônico). Avaliaram-se deposição de calda no dossel da cultura, perdas para o solo e deriva, pela técnica da adição de traçador para quantificação por espectrofotometria, e espectro de gotas, por meio da análise de papéis hidrossensíveis. A adição do adjuvante, de forma geral, proporcionou maior retenção de calda nas folhas inferiores e superiores. A diminuição do volume de aplicação proporcionou boa deposição de calda no alvo, sendo uma alternativa para aumento da capacidade operacional. A aplicação aérea mostrou-se tão eficiente quanto as aplicações terrestres na deposição de calda no alvo. A utilização do adjuvante não interferiu no diâmetro da mediana volumétrica e na percentagem do volume de gotas pulverizadas menores que 100 μm.

Influence of the sample area in the variability of losses in the mechanical harvesting of soybeans

The mechanical harvesting is an important stage in the production process of soybeans and, in this process; the loss of a significant number of grains is common. Despite the existence of mechanisms to monitor these losses, it is still essential to use sampling methods to quantify them. Assuming that the size of the sample area affects the reliability and variability between samples in quantifying losses, this paper aimed to analyze the variability and feasibility of using different sizes of sample area (1, 2 and 3 m²) in quantifying losses in the mechanical harvesting of soybeans. Were sampled 36 sites and the cutting losses, losses by other mechanisms of the combine and total losses were evaluated, as well as the water content in seeds, straw distribution and crop productivity. Data were subjected to statistical analysis (descriptive statistics and analysis of variance) and Statistical Control Process (SCP). The coefficients of variation were similar for the three frames available. Combine losses showed stable behavior, whereas cutting losses and total losses showed unstable behavior. The frame size did not affect the quantification and variability of losses in the mechanical harvesting of soybeans, thus a frame of 1 m² can be used for determining losses.

Evidence of hantavirus infection in wild rodents captured in a rural area of the state of São Paulo, Brazil

Hantaviruses are the etiological agents of the Hantavirus Cardio-Pulmonary Syndrome, a serious rodent-borne disease in Brazil. In order to investigate the occurrence of hantavirus infection in wild rodents, a survey was conducted in three different suburban areas of the municipality of Pedreira, State of São Paulo, Brazil. Of the 145 wild animals captured belonging to 12 different species identified by morphology and karyological analysis, 107 were rodents of the following species: Akodon montensis, Bolomys lasiurus, Calomys tener, Oligoryzomys nigripes, Oligoryzomys flavescens, and Myocastor coypus. Blood samples from these rodents were assayed for the presence of antibodies against hantavirus by IgG ELISA using Andes recombinant nucleocapsid antigen. Antibody reactive to Andes virus was found in two different species, O. nigripes and O. flavescens. These results indicate a potential risk for hantavirus transmission to humans in this area, where reservoir rodents are present in peridomestic settings.

Trypanosoma vivax infection dynamics in a cattle herd maintained in a transition area between Pantanal lowlands and highlands of Mato Grosso do Sul, Brazil

Trypanosoma vivax outbreaks in beef cattle in the Pantanal region of Mato Grosso do Sul state, Brazil, causes relevant economical impact due to weight loss, abortion and mortality. Cattle moved from the Pantanal to adjacent areas of this ecosystem for breeding and fattening is a common feature. Therefore an epidemiological study on breeding cows in the transition area between Pantanal lowland and adjacent highlands of Mato Grosso do Sul was performed to determine the T. vivax infection dynamics and outbreak risk. Three experimental groups were formed: Group 1 consisted of cows parasitologically negative by the Woo test and in the enzyme-linked immunosorbent assay for T. vivax antibody detection (Tv-ELISA-Ab); Group 2 parasitologically negative and positive in the Tv-ELISA-Ab; and in Group 3 cows were parasitologically positive and with positive reactions in the Tv-ELISA-Ab. During 24 months, the cows' dislodgment between the above established groups was monitored by Woo test and Tv-ELISA-Ab exams. The tabanid population was also monitored and the highest number occurred during the rainy season. Although parasitemias were detected only in the first four samplings of the experimental period, the cows could be considered as trypanotolerant, because no clinical signs were observed. Despite the higher T. vivax incidence during the dry season, no disease symptoms were seen. Even though T. vivax epidemiological situation in the herd was characterized as endemic with seasonal variation, the probability of outbreaks was null within the conditions of the study.

Importância do diâmetro das gotas de pulverização na deriva de defensivos agrícolas em aplicação aérea

Foi conduzido um experimento no município paulista de Barra Bonita, com aplicações aéreas, onde foram comparadas as distâncias de deriva apresentadas por bicos de diversos tipos posicionados em ângulos diferentes. As aplicações foram feitas com uma solução de água contendo 0,1% de corante Lissamine Turquesa, com gasto de 30 1/ha. Os resultados mostraram a influência do ângulo formado pelos bicos em sua colocação na barra de pulverização e a influência do diâmetro das gotas de pulverização no efeito da deriva. Os bicos cônicos D8-45 montados com capa < •Raindrop - reduziram significativamente o tamanho das gotas, o mesmo acontecendo com o bico < •Solid Stream, posicionado a 45°.

Nota científica: métodos para estimativa da area foliar de plantas daninhas: 2: Wissadula subpeltata (Kuntze) Fries

Com o objetivo de obter uma equação que, através de parâmetros lineares dimensionais das folhas, permitisse estimar a área foliar de Wissadula subpeltata (Kuntze) Fries, estudaram- se correlações entre a área foliar real e o comprimento da folha ao longo da nervura principal (C ), largura máxi ma da folha (L) , comprimento do espaço entre o ponto de inserção do pecíolo na folha até a primeira ramificação da nervura principal (CE), L + C, L x C e L x CE. Todas as equações, geométricas ou lineares simples, permitiram boas estimativas da área foliar . Do pont o de vista prático, sugere- se optar pela equação linear simples envolvendo o produto C x L, considerando o coeficiente linear igual a zero. Deste modo, a estimativa da área foliar de W. subpeltata pode ser feita pel a fórmula Y = 0, 85 49 (C x L), ou seja 85 ,49% do produto entre o comprimento da nervura principal e a largura máxima da folha.

Métodos para estimativa da area foliar de plantas daninhas: 4 , Cassia tora L.

O trabalho analisa as possibilidades das estimativas das áreas (9) de folíolos do ápice, meio e base de folhas de Cassia tora L., através das equações lineares (Y = A + BX ) e (Y = BX), geométricas ou potenciais (Y= A XB ) e exponenciais (Y = ABX ). O valor de X e tomado das medidas lineares do folíolo, a saber: comprimento da nervura principal (C) , largura máxima perpendicular à nervura principal (L) ou o produto C.L. A análise de 360 folíolos mostra que as áreas podem ser estimadas de maneira proporcional ao retângulo C x L. Os coeficientes de correção foram 0,6711 para os foliolos do ápice, 0,7404 para as medianas e 0,7759 para as da base. Houve diferenças estatisticamente significativas entre os coeficientes, não sendo possível estabelecer-se um único coeficiente para os três folíolos.

Efeito do 2,4-D e do glifosate no controle da parte aérea e dos rizomas da losna

A losna (Artemisia verlotorum) é uma planta daninha com alta capacidade de rebrota de seus rizomas e tolerante à maioria dos herbicidas, principalmente os de contato, o que dificulta consideravelmente o seu controle químico e mecânico. O 2,4-D, na dose de 1,662 kg/ha (por interpolação), reduziu o número de plantas vivas de losna de 34 para 6 aos 30 dias após sua aplicação, enquanto que, o glifosate, na dose de 0,856 kg/ha, reduziu esse número de 27 para 10. O glifosate, na dose de 0,811 kg/ha, aos 60 dias após a sua aplicação, reduziu o número de plantas vivas de losna de 34 para 18, enquanto o 2,4-D não mais apresentou efeito. Aos 90 dias não foi verificado nenhum efeit o dos dois produtos sobre a losna, em condições de campo. Em casa-de-vegetação verificou-se uma menor capacidade de rebrota dos rizomas com a aplicação do glifosate, enquanto o 2,4-D não mostrou efeito satisfatório. Ocorreu maior redução no peso da matéria secada parte aérea e dos rizomas, quando se aplicou o glifosate nas doses 1,0 e 0,865 kg/ha, respectivamente. Contudo, o menor valor obtido para aérea foliar da losna foi alcançado quando se aplicou 0,983 kg/ha de glifosate.

Composicion y variabilidad espacialdel banco de semillas de malezas en un area agricolade azul (Argentina)

No Distrito Azul, zona central da província de Buenos Aires (Argentina), encontram-se ambientes de planície na parte norte e ambientes serranos na parte sul. Esta última, constituí-se numa área predominantemente agrícola, onde a cultura de trigo, principal atividade agrícola, se alterna com culturas de verão como milho, girassol e soja. Com o objetivo de caracterizar globalmente o banco de sementes da área agrícola, foram analisados o conteúdo de sementes, a composição de espécies, a distribuição e variabilidade espacial das espécies que o compõem. A informação básica foi obtida aplicando-se a técnica da emergência em amostras de solo correspondentes a 20 locais alinhados numa faixa de 14 km. A densidade de sementes nos locais de amostragem variou entre 1.173 e 44.000 sem/m2. Na totalidade, foram detectadas 33 espécies. Digitaria sanguinalis foi claramente a espécie dominante, aportando com quase 43 % do banco, seguida de Polygonum aviculare com um aporte de 15 %. As duas espécies, juntamente com Anagallis arvensis e Setaria viridis completam70 % do banco de sementes. A composição específica completa-se com um grupo de 29 espécies, os quais contribuem, cada um delas, com menos de 5%. A distribuição espacial das espécies ao longo da faixa estudada mostrou um grau de agregação variável, sendo encontrada uma correlação positiva significativa entre o tamanho do banco e a relação variância/média. Demonstrou-se, assim, que as espécies mais abundantes em média, apresentaram grande variabilidade espacial. Nelas, foram observados diferentes padrões de distribuição espacial.

Descripción de las especies del género Ipomoea presentes en el area de riego del río Dulce, Santiago del Estero, Argentina

El objetivo del presente trabajo fue relevar y diferenciar especies del género Ipomoea presentes en diferentes fases de desarrollo, en el área de riego del Río Dulce, Santiago del Estero, Argentina. Para ello fueron herborizados y fotografiados diversos ejemplares encontrados en la región. En el laboratorio, después del trabajo de identificación, fueron descritas las diversas fases de desarrollo de la planta: semilla, plántula y estado adulto, creándose códigos de identificación para cada fase. Se registraron ocho especies del género Ipomoea, I. alba; I. amnicola; I. cairica; I. carnea; I. grandifolia; I. nil; I. purpurea e I. quamoclit, algunas de las cuales se cultivan como ornamentales, otras aparecen como ruderales y algunas son malezas en cultivos de la región.

Weed control in young coffee plantations through post emergence herbicide application onto total area

This study was carried out to investigate the efficiency of several herbicides under field conditions, by post-emergence application onto the entire area, their effect on the control of weeds in young coffee plantations and commercial coffee and bean intercropping system, as well as on both crops. Seedlings of Coffea arabica cv. Red Catuaí with four to six leaf pairs were transplanted to the field and treated according to conventional agronomic practices. A bean and coffee intercropping system was established by sowing three lines of beans in the coffee inter-rows. At the time the herbicides were sprayed, the coffee plants had six to ten leaf pairs; the bean plants, three leaflets; and the weeds were at an early development stage. Fluazifop-p-butyl and clethodim were selective for coffee plants and controlled only Brachiaria plantaginea and Digitaria horizontalis efficiently. Broad-leaved weeds (Amaranthus retroflexus, Bidens pilosa, Coronopus didymus, Emilia sonchifolia, Galinsoga parviflora, Ipomoea grandifolia, Lepidium virginicum, and Raphanus raphanistrum) were controlled with high efficiency by sole applications of fomesafen, flazasulfuron, and oxyfluorfen, except B. pilosa, C. didymus, and R. raphanistrum for oxyfluorfen. Sequential applications in seven-day intervals of fomesafen + fluazifop-p-butyl, or clethodim, and two commercial mixtures of fomesafen + fluazifop-p-butyl simultaneously controlled both types of weed. Cyperus rotundus was only controlled by flazasulfuron. Except for fluazifop-p-butyl and clethodim, all herbicide treatments caused only slight injuries on younger coffee leaves. However, further plant growth was not impaired and coffee plant height and stem diameter were therefore similar in the treatments, as evaluated four months later. Fomesafen, fluazifop-p-butyl, and clethodim, at sole or sequential application, and the commercial mixtures of fomesafen + fluazifop-p-butyl were also highly selective for bean crop; thus at doses recommended for bean crop, these herbicides may be applied to control weeds in coffee and bean intercropping systems by spraying the entire area.