RESUMO

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)

Assuntos

RESUMO

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.

Assuntos

RESUMO

The aim of this study was to employ the principal component technique to physiological data and environmental thermohygrometric variables correlated with detection of clinical and subclinical mastitis in dairy cattle. A total of 24 lactating Girolando cows with different clinical conditions were selected (healthy, and with clinical or subclinical mastitis). The following physiological variables were recorded: udder surface temperature, ST (°C); eyeball temperature, ET (°C); rectum temperature, RT (°C); respiratory frequency, RF (mov. min-1). Thermohygrometric variables included air temperature, AirT (°C), and relative humidity, RU (%). ST was determined by means of thermal images, with four images per animal, on these quarters: front left side (FL), front right side (FR), rear right side (RR) and rear left side (RL), totaling 96 images. Exploratory data analysis was run through multivariate statistical technique with the employment of principal components, comprehending nine variables: ST on the FL, FR, RL and RR quarters; ET, RT; RF, AirT and RU. The representative quarters of the animals with clinical and subclinical mastitis showed udder temperatures 8.55 and 2.46° C higher than those of healthy animals, respectively. The ETs of the animals with subclinical and clinical mastitis were, respectively, 7.9 and 8.0% higher than those of healthy animals. Rectum temperatures were 2.9% (subclinical mastitis) and 5.5% (clinical mastitis) higher compared to those of healthy animals. Respiratory frequencies were 40.3% (subclinical mastitis) and 61.6% (clinical mastitis) higher compared to those of healthy animals. The first component explained 91% of the total variance for the variables analyzed. The principal component technique allowed verifying the variables correlated with the animals' clinical condition and the degree of dependence between the study variables.

Assuntos

RESUMO

The aim of this study was to employ the principal component technique to physiological data and environmental thermohygrometric variables correlated with detection of clinical and subclinical mastitis in dairy cattle. A total of 24 lactating Girolando cows with different clinical conditions were selected (healthy, and with clinical or subclinical mastitis). The following physiological variables were recorded: udder surface temperature, ST (°C); eyeball temperature, ET (°C); rectum temperature, RT (°C); respiratory frequency, RF (mov. min-1). Thermohygrometric variables included air temperature, AirT (°C), and relative humidity, RU (%). ST was determined by means of thermal images, with four images per animal, on these quarters: front left side (FL), front right side (FR), rear right side (RR) and rear left side (RL), totaling 96 images. Exploratory data analysis was run through multivariate statistical technique with the employment of principal components, comprehending nine variables: ST on the FL, FR, RL and RR quarters; ET, RT; RF, AirT and RU. The representative quarters of the animals with clinical and subclinical mastitis showed udder temperatures 8.55 and 2.46° C higher than those of healthy animals, respectively. The ETs of the animals with subclinical and clinical mastitis were, respectively, 7.9 and 8.0% higher than those of healthy animals. Rectum temperatures were 2.9% (subclinical mastitis) and 5.5% (clinical mastitis) higher compared to those of healthy animals. Respiratory frequencies were 40.3% (subclinical mastitis) and 61.6% (clinical mastitis) higher compared to those of healthy animals. The first component explained 91% of the total variance for the variables analyzed. The principal component technique allowed verifying the variables correlated with the animals' clinical condition and the degree of dependence between the study variables.(AU)

Assuntos

RESUMO

The objective of this research was to assess the spatial variability pattern concerning udder surface temperature in dairy cows that were healthy and in those with mastitis. A total of 24 animals were selected - eight healthy, eight with subclinical mastitis, and eight with clinical mastitis. Images were taken with a Flir i60 thermographic camera - resolution of 0.01°C, focal length of 1.0 m, and emissivity adjusted to 0.98 - between 05:00 and 07:00, totaling 96 images, three per animal, of the front and rear, right and left mammary quarters. Analyses were run through geostatistics, with semivariogram adjustment to validate the theoretical model and build kriging maps. The average surface temperature of the mammary quarters with positive classification for subclinical mastitis stood between 33.2 ± 0.67ºC and 34.64± 1.07ºC; for negative quarters, values ranged from 29.3 ± 1.78ºC to 32.24 ± 0.62ºC. The udder surface temperatures of healthy animals were lower than those of animals with subclinical mastitis (29.3ºC ± 1.78 and 31.58ºC ± 0.62). The udder surface temperature of animals with clinical mastitis was higher, between 34.0 and 37.5°C, compared to the other clinical statuses. The scale adopted for image pattern analysis successfully identified the spatial dependence of udder surface temperature, which helped standardize diagnostic procedures for healthy animals, and for those with subclinical and clinical mastitis, by means of geostatistics.(AU)

Objetivou-se com essa pesquisa avaliar o padrão de variabilidade espacial da temperatura de superfície do úbere de vacas leiteiras saudáveis e com mastite. Foram selecionados 24 animais, oito saudáveis, oito com mastite subclínica e oito com mastite clínica. As imagens foram obtidas a partir de uma câmera termográfica Flir i60, resolução de 0,01 °C, 1,0 m de distância focal e emissividade ajustada para 0,98. O horário de realização das imagens foi entre às 05 e 07h00, que totalizaram 96 imagens, três por animal, nos enquadramentos anterolateral direito, anterolateral esquerdo, posterior e inferior. As análises foram realizadas pela geoestatística, com ajuste do semivariograma para validação do modelo teórico e construção dos mapas de krigagem. A temperatura média de superfície dos quartos mamários com classificação positiva para mastite subclínica apresentou valores entre 33,2 ± 0,67ºC e 34,64± 1,07ºC; para os quartos negativos entre 29,3 ± 1,78ºC e 32,24 ± 0,62ºC. Os animais saudáveis apresentaram temperatura de superfície de úbere inferior àqueles com mastite subclínica (29,3ºC ± 1,78 e 31,58ºC ± 0,62). A temperatura da superfície do úbere dos animais com mastite clínica foi mais elevada, entre 34,0 e 37,5°C, comparativamente aos demais quadros clínicos. A escala adotada para análise do padrão das imagens identificou com sucesso a dependência espacial da temperatura de superfície do úbere, o que contribuiu para padronização dos procedimentos de diagnóstico para animais saudáveis, com mastite subclínica e clínica, por meio da geoestatística.(AU)

Assuntos

RESUMO

The objective of this research was to assess the spatial variability pattern concerning udder surface temperature in dairy cows that were healthy and in those with mastitis. A total of 24 animals were selected - eight healthy, eight with subclinical mastitis, and eight with clinical mastitis. Images were taken with a Flir i60 thermographic camera - resolution of 0.01°C, focal length of 1.0 m, and emissivity adjusted to 0.98 - between 05:00 and 07:00, totaling 96 images, three per animal, of the front and rear, right and left mammary quarters. Analyses were run through geostatistics, with semivariogram adjustment to validate the theoretical model and build kriging maps. The average surface temperature of the mammary quarters with positive classification for subclinical mastitis stood between 33.2 ± 0.67ºC and 34.64± 1.07ºC; for negative quarters, values ranged from 29.3 ± 1.78ºC to 32.24 ± 0.62ºC. The udder surface temperatures of healthy animals were lower than those of animals with subclinical mastitis (29.3ºC ± 1.78 and 31.58ºC ± 0.62). The udder surface temperature of animals with clinical mastitis was higher, between 34.0 and 37.5°C, compared to the other clinical statuses. The scale adopted for image pattern analysis successfully identified the spatial dependence of udder surface temperature, which helped standardize diagnostic procedures for healthy animals, and for those with subclinical and clinical mastitis, by means of geostatistics.

Objetivou-se com essa pesquisa avaliar o padrão de variabilidade espacial da temperatura de superfície do úbere de vacas leiteiras saudáveis e com mastite. Foram selecionados 24 animais, oito saudáveis, oito com mastite subclínica e oito com mastite clínica. As imagens foram obtidas a partir de uma câmera termográfica Flir i60, resolução de 0,01 °C, 1,0 m de distância focal e emissividade ajustada para 0,98. O horário de realização das imagens foi entre às 05 e 07h00, que totalizaram 96 imagens, três por animal, nos enquadramentos anterolateral direito, anterolateral esquerdo, posterior e inferior. As análises foram realizadas pela geoestatística, com ajuste do semivariograma para validação do modelo teórico e construção dos mapas de krigagem. A temperatura média de superfície dos quartos mamários com classificação positiva para mastite subclínica apresentou valores entre 33,2 ± 0,67ºC e 34,64± 1,07ºC; para os quartos negativos entre 29,3 ± 1,78ºC e 32,24 ± 0,62ºC. Os animais saudáveis apresentaram temperatura de superfície de úbere inferior àqueles com mastite subclínica (29,3ºC ± 1,78 e 31,58ºC ± 0,62). A temperatura da superfície do úbere dos animais com mastite clínica foi mais elevada, entre 34,0 e 37,5°C, comparativamente aos demais quadros clínicos. A escala adotada para análise do padrão das imagens identificou com sucesso a dependência espacial da temperatura de superfície do úbere, o que contribuiu para padronização dos procedimentos de diagnóstico para animais saudáveis, com mastite subclínica e clínica, por meio da geoestatística.

Assuntos