RESUMEN
The objective of this research is to apply exploratory analysis and modeling associated with abiotic factors, physiological and behavioral variables of swine in the semi-arid region. The experimental design used was completely randomized, in a 3 × 3 factorial scheme, randomly distributed in nine pens, with three animals. The behavior of the animals was recorded using images and analyzed within 10-min interval. The data analysis used was multivariate, using the clustering method (tree diagram) and principal component analysis (PCA), in order to establish the main predictors of swine ingestive behavior, using multiple linear regression models. The PCA showed satisfactory results, in which the lowest eigenvalue observed was 2.82 and the accumulated variance for the treatments ranged from 69.70 to 94% for the first two principal components. Through exploratory data analysis, it was possible to identify the relationship between biotic and abiotic factors with the ingestive behavior of pigs in the finishing phase. Based on the results of the multivariate analysis, the most promising predictor variables for estimating the regression models were determined. Adiabatic evaporative cooling associated with 18 h of light was the combination of factors with the best results, presenting models for eating and drinking behavior, i.e. a complete ingestive characterization.
Asunto(s)
Conducta de Ingestión de Líquido , Conducta Alimentaria , Animales , Porcinos , Análisis por Conglomerados , Frío , Análisis de DatosRESUMEN
Heat stress is one of the most important environmental challenges faced by dairy cattle, with a deleterious effect on animal production and welfare. This research was conducted to evaluate the effects of the thermal environment on the physiological and behavioral responses of dairy cattle in a rotational picket. The research was conducted on an experimental farm, located in the Agreste region of the state of Pernambuco, Brazil. The animals were managed in a rotational picket system of signal grass, with an occupation and a rest period of 7 and 28 days, respectively, for a stocking rate of 3.2 AU ha-1. The determination of the effect of stressors on the animals was performed by recording the dry bulb temperature (°C), and the relative humidity, which allowed the characterization of the thermal environment by the temperature and humidity index and by the specific enthalpy (kJ kg-1). The physiological variables monitored were respiratory rate (mov. min-1), rectal temperature (°C), and skin temperature (°C). The behavioral responses quantified were activities, walking, ruminating, idling and ingestive behaviors, eating, and drinking, with the percentage of time spent on each activity being recorded. According to the canonical multivariate analysis, the chi-square test, and the variation of physiological patterns, the animals, even in a situation of greater thermal challenge, presented physiological responses within conditions considered normal; however, they reduced grazing activity (eating) during the hottest hours and increased the activities of rumination and idling.
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Adaptación Fisiológica , Calor , Animales , Bovinos , Femenino , Temperatura Corporal , Conducta Alimentaria , Humedad , Lactancia/fisiología , Temperatura , Métodos de Alimentación , Conducta AnimalRESUMEN
The continuous use of fertilizers can increase the radionuclides levels in soils, and their accumulation and concentration are related to their characteristics and the various processes of use and soil occupation. Analyzing data from radiometric and pedological measurements often demands the use of more robust tools for better integration of results. This work presents the results of a study to evaluate the accumulation of 40K, in an area of the Zona da Mata region in Pernambuco, Northeastern Brazil, due to the contribution of natural or artificial sources. 40K activity concentration was measured by high resolution gamma spectrometry in 108 soil samples, as well the organic matter content and particle size distribution. Results showed the 40K activity ranged from 103 to 1843 Bq.Kg-1, with the arable soils showing levels above the world average value (420 Bq.Kg-1). A higher prevalence of 40K was observed on arable soils, regardless of soil type, organic matter content, depth or texture. Agricultural activities increased of 40K levels in different degrees, depending on the type of crop used, with an accumulation factor of up to 4 times greater compared to soils not impacted by agricultural activities. The radiochemometric diagnosis maded it possible to draw up a strategic management plan to improve the management practices of family farming in order to maximize production efficiency, and promote the conservation of natural resources and environmental preservation.
Asunto(s)
Monitoreo de Radiación , Suelo , Agricultura , Brasil , Quimiometría , Monitoreo de Radiación/métodos , Radioisótopos/análisis , Suelo/químicaRESUMEN
This study aimed to analyze the principal componentsof the meteorological variables, physiological and behavioral response of cowssubjected to different coolingtimes and their influence on milk quality, in the dryand rainfallperiods, and to establish multiple regression models for milk quality. The data used in the study came from an experiment conducted in the Agreste Region of Pernambuco.The pre-milking coolingtime was 10, 20, 30 min.and the control (without cooling). Sixteen multiparous lactating Gir cows were selected. Data were analyzed by principal component analysis and a multiple regression analysis was applied to determine milk quality. There was a strong relationship between somatic cell count (SCC) and activity of the animal in the shade for dry,and lying for rainfall, with increased SCC in cow milk. It was possible to establish two multiple regression models to determine milk quality in dryand rainfall periods. According to the principal component analysis, the coolingtime tomeet the thermal requirement of the animals was 20 min., regardless of the season and milking shift.
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Femenino , Animales , Bovinos , Bovinos , Conceptos Meteorológicos , Células Híbridas , Leche/químicaRESUMEN
This study aimed to analyze the principal componentsof the meteorological variables, physiological and behavioral response of cowssubjected to different coolingtimes and their influence on milk quality, in the dryand rainfallperiods, and to establish multiple regression models for milk quality. The data used in the study came from an experiment conducted in the Agreste Region of Pernambuco.The pre-milking coolingtime was 10, 20, 30 min.and the control (without cooling). Sixteen multiparous lactating Gir cows were selected. Data were analyzed by principal component analysis and a multiple regression analysis was applied to determine milk quality. There was a strong relationship between somatic cell count (SCC) and activity of the animal in the shade for dry,and lying for rainfall, with increased SCC in cow milk. It was possible to establish two multiple regression models to determine milk quality in dryand rainfall periods. According to the principal component analysis, the coolingtime tomeet the thermal requirement of the animals was 20 min., regardless of the season and milking shift.(AU)
Asunto(s)
Animales , Femenino , Bovinos , Bovinos , Leche/química , Conceptos Meteorológicos , Células HíbridasRESUMEN
An approach pooling geochemical analyses and ecotoxicological tests has been applied to assess the sediment quality of the Capibaribe River Estuary, Brazil. Toxicity tests were performed to compare a well-established, labor-intensive protocol using ovigerous females to a new, easier and faster protocol using nauplii of the epibenthic marine copepod Tisbe biminiensis. The endpoints of the nauplii toxicity test were comparable to those of the female test. Nauplii proved to be more sensitive than females as a biological model for indicating sediment toxicity. All sediments collected had at least one contaminant above the threshold effects level (TEL) proposed in the literature. Furthermore, more than one-third of samples exhibited contaminants above the probable effects level (PEL). The PCA revealed that nauplii mortality was associated with metals in October 2014, which was confirmed by the Spearman correlation factor. In contrast, no strong association among contaminants and toxicological endpoints in May 2015 was found.