ABSTRACT
The objective was to establish a model for the prediction and characterization of vaginal temperature in Holstein cows, based on environmental predictors and thermal comfort indices, through cluster analysis, validation by the cophenetic correlation coefficient, and multiple regression analysis. The micrometeorological characterization of the site was carried out by recording the air temperature (Tair), the relative humidity (RH), the black globe temperature (BGT), the black globe temperature and humidity (BGHI), and dew point temperature (TDP). The recording of vaginal temperature (Tv) was performed in eight dairy cows using temperature sensors, equipped with data loggers, coupled with intravaginal devices. The data were analyzed using descriptive statistics and cluster analysis (CA) by using the hierarchical agglomerative method based on the value of the cophenetic correlation coefficient (CCC >0.70), in which representative physiological models were established, characterizing the Tv through multiple regression. In the afternoon the coefficient of variation (CV) was low for all variables, indicating homogeneity of the meteorological variables and efficiency of the ventilation system. The temperature and humidity index (THI) was mild only on the morning. There was a variation of 0.28 °C of Tv between shifts, sufficient to characterize the condition of comfort and stress of the animal, with values above 39 °C indicating animal stress. Tv showed strong correlation with BGT, Tair, TDP and RH, assuming that physiological variables, such as Tv, tend to have greater relationship with abiotic variables. Empirical models were established for estimating Tv based on the analyses performed in this study. Model 1 is recommended for TDP ranges of 14.00-21.00 °C and RH of 30-100%, while model 2 can be used for Tair situations up to 35 °C. The regression models for estimating Tv are promising for characterizing the thermal comfort of dairy cows housed in compost barn systems.
Subject(s)
Body Temperature , Lactation , Animals , Female , Cattle , Temperature , Humidity , Cluster Analysis , DNA-Binding Proteins , Hot TemperatureABSTRACT
ABSTRACT: The efficiency of the disinfectants used in the milking management is fundamental to the success in the dairy activity, being a critical point to the control of mastitis. The objective was to evaluate the in vitro efficacy of iodine used in pre and post-dipping against coagulase negative Staphylococcus (CNS). Thus, 53 CNS isolates were studied for the action of the 1.0% disinfectant and their serial dilutions of 0.5%, 0.375% and 0.25%, in addition to two commercial presentations of iodine in concentrations of 0.5% and 0.25%. The rate of CNS inhibition achieved by iodine at 0.375%, 0.5% and 1.0% for 60 seconds, was 60.4%. In 30 seconds, iodine at 0.5% and 1.0% showed a microbial inhibition rate of 52.8% and 56.6%, respectively. The other protocols tested were less efficient. It is concluded that the greatest in vitro disinfectant activity for CNS was demonstrated by iodine at 0.375%, 0.5% and 1.0%, for 60 seconds. Microbial susceptibility tests should be carried out periodically, as well as health education practices and corrective training on the property, in order to ensure udder health and mastitis control.
RESUMO: A eficiência dos desinfetantes empregados no manejo de ordenha é fundamental no sucesso na atividade leiteira, sendo um ponto crítico ao controle da mastite. Objetivou-se avaliar a eficácia in vitro do iodo utilizado no pré e pós-dipping frente à Staphylococcus coagulase negativa (SCN). Foram estudados 53 isolados de SCN quanto à ação do desinfetante a 1,0% e suas diluições seriadas de 0,5%, 0,375% e 0,25%, além de duas apresentações comerciais nas concentrações de 0,5% e 0,25%. A taxa de inibição de SCN alcançada pelo iodo a 0,375%, 0,5% e 1,0% durante 60 segundos, foi de 60,4%. Em 30 segundos, o iodo a 0,5% e 1,0% apresentaram taxa de inibição microbiana de 52,8% e 56,6%, respectivamente. Os demais protocolos testados foram menos eficientes. Conclui-se que a maior atividade desinfetante in vitro para SCN foi demonstrada pelo iodo a 0,375%, 0,5% e 1,0%, durante 60 segundos. Testes de susceptibilidade microbiana devem ser realizados periodicamente, assim como práticas de educação em saúde e treinamentos corretivos na propriedade, visando garantir a saúde do úbere e o controle da mastite.
ABSTRACT
The assessment of environmental conditions in the creation of dairy cattle in feedlots must be carried out to identify possible causes of stress and assist producers in the decision-making process. The objective was to characterize the abiotic factors and bed temperature, in the comfort conditions of dairy cows, through geostatistics and exploratory data inference, in a Compost Barn System in the Brazilian semiarid region. The data were obtained in a milk production unit, located in the municipality of Lajedo, Pernambuco, Brazil. The variables air temperature (Tair), relative humidity (RH), wind speed (WS), illuminance (Lux), skin temperature (Ts), bed temperature (Tb) were recorded and the temperature index was determined and humidity (THI). Data were recorded at 9:00 a.m., 12:00 p.m., and 03:00 p.m., over 5 days in the summer season. For geostatistical analysis, the classic semivariances were determined. The principal component analysis was performed to establish an index that characterized the condition of animal comfort. The variables Tair, RH, Tb, and THI showed a low coefficient of variation for all times. The best fit to the models of the semivariograms was the Gaussian at 9:00 a.m. and 03:00 p.m., and the spherical at 12:00 p.m. The Tb spatial variability was low for all studied hours. Tair showed a strong correlation with Tb, due to the process of heat transfer by convection from the floor to the environment. Geostatistics and exploratory data analysis allowed the establishment of a comfort index for Compost Barn production systems in the Brazilian semiarid region (R2 = 0.996; p < 0.0001).
Subject(s)
Cattle/physiology , Dairying , Housing, Animal , Temperature , Animals , Climate , Composting , Female , Humidity , Skin Temperature , Spatial Analysis , WindABSTRACT
ABSTRACT: This research aimed to assess Girolando calves' concentrate intake and performance when placed in shelters with distinct roofing materials and programs of supplementary lighting during the milk-feeding stage. In order to so, we used a completely randomized design with a 3×3 factorial arrangement, with three replications. Females Girolando calves (n=27) were assigned in individual shelters at random with 3 different roofing materials (fiber cement tile, recycled tile and thatched roofs) and subjected to three lighting programs (12, 16 and 20 hours). No interaction was observed between roofing material and lighting programs, whilst no significant effect (P>0.05) was observed among the roofing materials. The supplementary lighting, by providing greater light exposure time, has stimulated intake and therefore, significantly affected (P<0.05) the concentrate intake and performance of the animals that were subjected to 20 hours of light.
RESUMO: Essa pesquisa teve como objetivo avaliar o consumo de concentrado e o desempenho de bezerras da raça Girolando quando colocadas em abrigos com materiais de cobertura e programas de iluminação suplementar distintos, durante a fase de aleitamento. Para tal, nós utilizamos o delineamento experimental inteiramente casualizado em arranjo fatorial 3×3, com três repetições. As bezerras Girolando (n=27) foram distribuídas ao acaso em abrigos individuais, com materiais de cobertura distintos (telha de fibrocimento, telha reciclada e cobertura com palha), e sujeitas a três programas de iluminação (12, 16 e 20h). Não houve interação entre os mateiral de cobertura×programas de iluminação, ao mesmo tempo que não foi observado efeito significativo (P>0,05) para os materiais de cobertura. A iluminação suplementar, proporcionando maior tempo de luz, tem estimulado a ingestão, e, portanto, apresentou efeito significativo (P<0,05) no consumo de concentrado e desempenho dos animais submetidos a 20h de iluminação.
