Infrared thermal image for assessing animal health and welfare

Infrared thermal imaging is a non-destructive testing technology that can be used to determine the superficial temperature of objects. This technology has an increasing use in detecting diseases and distress in animal husbandry within the poultry, pig and dairy production. The process can identify changes in peripheral blood flow from the resulting changes in heat loss and; therefore, have been a useful tool for evaluating the presence of disease, edema, and stress in animals. This paper reviews the current literature related to the use of infrared technology and discusses their results and implications in animal welfare issues, poultry, pig and bovine industry

Applications of thermal imaging in avian science

Thermal imaging, or infrared thermography, has been used in avian science since the 1960s. More than 30 species of birds, ranging in size from passerines to ratites, have been studied using this technology. The main strength of this technique is that it is a non-invasive and non-contact method of measuring surface temperature. Its limitations and measurement errors are well understood and suitable protocols have been developed for a variety of experimental settings. Thermal imaging has been used most successfully for research on the thermal physiology of captive species, including poultry. In comparison with work on mammals, thermal imaging has been less used for population counts, other than for some large bird species. However, more recently it has shown greater success for detection of flight paths and migration. The increasing availability and reduced cost of thermal imaging systems is likely to lead to further application of this technology in studies of avian welfare, disease monitoring, energetics, behaviour and population monitoring

Distribuição da temperatura superficial de frangos de corte com 42 dias de idade

Broiler chickens in Brazil are generally reared from 1 to 42 days when they are exposed to procedures such as fasting, harvesting, crating and transport to slaughter. Maintaining homeostasis is of great importance for broiler survival under harsh environment especially prior to slaughter. Heat loss varies in the distinct parts of the body during the growth period, and it is related to the air temperature of the environment and to the amount of feather covering. This research aimed to study the surface temperature distribution using infrared thermographic image processing to characterize 42 day old broiler chicken surface temperature prior to slaughter. Broilers were reared for 42 days and prior to harvest and transport to slaughter the infrared surface temperature was recorded along the day. Data from the thermograms taken in feather and featherless regions were compared during the 42nd day of growth. High correlation between featherless regions and air temperature was found showing that these areas respond fast to changes in the rearing environment. Two functions were developed for predicting both surface temperature for featherless and feather covered areas of the broiler body parts.No Brasil frangos de corte são normalmente alojados de 1 até 42 dias, quando são expostos a procedimentos como: jejum, apanha, colocação em caixas e transporte até o abate. Manter a homeostase do corpo é de grande importância para a sobrevivência de frangos de corte sob ambiente quente, especialmente na 7ª semana de crescimento. A perda de calor varia nas partes do corpo e está relacionada à temperatura do ar e à cobertura de penas. Avaliou-se a distribuição da temperatura superficial usando o processamento de imagens de câmera termográfica infravermelho, para caracterizar a temperatura superficial de frangos de corte de 42 dias de idade, no período anterior à apanha para o abate. Os frangos foram alojados de 1 a 42 dias e, antes de serem apanhados e transportados para o abate, foram registradas temperaturas superficiais infravermelho durante o dia.. Os resultados dos termogramas das regiões com penas e sem penas foram comparados, durante o 42º dia. Alta correlação entre regiões sem penas e a temperatura ambiente foi encontrada, mostrando que estas áreas respondem rapidamente a alterações no ambiente do alojamento. Duas funções foram desenvolvidas para predizer a temperatura superficial das regiões com e sem penas, do corpo de frangos com 42 dias, sendo conhecida a temperatura do ar do ambiente

Measuring Energetics of Biological Processes

Measurement of the energetics of biological processes is the key component in understanding the thermodynamic responses of homoeothermic animals to their environments. For these animals to achieve body temperature control, they must adapt to thermal-environmental conditions and variations caused by weather (the meteorological condition of a region), climate, vegetation, topography, and shelters (see Figures 2 and 3 of Chapter 1). Adaptation can take different forms as defined by Hafez (1968). Physiological adaptation is the capacity and process of adjustment of the animal to itself, to other living material, and to its external physical environment. Genetic adaptation refers to the selection and heritability of characteristics for a particular environment or climatic region. A long-term adaptive physiological adjustment is referred to as acclimatization. We know this occurs through observations of animal conformation, animal types, respiratory rate, color, behavior, food selection, etc. Since adaptation of the animal to its thermal environment requires regulation of body temperature, measurement of that adaptation through animal energetics provides an indicator of the extent and energetic cost of adaptation

Effect of heat and physiological stress on the growth performance, physiology and welfare of broiler chickens

PhD ThesisBroilers can be faced with a several stressful conditions during their production cycle which can have implications for both growth performance and animal welfare. Animal welfare encompasses the physical and mental well-being of animals, assessed from the biological functioning and subjective experience. The aims of this thesis were i) to develop and validate non-invasive means of assessing the welfare of broilers under physiological and episodic heat stress conditions, ii) to investigate the impact of episodic heat stress, physiological stress and light wavelength on the growth performance, physiology and welfare of broiler chickens and, finally, iii) to investigate a novel means of alleviating heat stress in broilers. Endogenous corticosterone measured in the urate sphere was suppressed by dexamethasone administration. In a cognitive bias task, birds offered mealworms injected with corticosterone to mimic chronic stress were pessimistic in their judgement about ambiguous positions. A positive correlation was established between physiological indicators of stress and cognitive bias. Although light wavelength was confounded with light intensity in our study, there was no difference in growth performance and cognitive ability of birds reared in the blue and red light, except for increased activity of birds in red light. Under simulated episodic heat stress, the change in CBT measured from a temperature-ID chip (ΔCBT-chip) and a data logger (ΔCBT-logger) was positively correlated. Significant positive correlations were found between the change in surface body temperature (SBT) under wing (ΔWT) and ΔCBT-chip, and between ΔWT and ΔCBT-logger. Significant positive regression equations relating change in CBT and RR with apparent equivalent temperature (a factor which combines environmental temperature and RH) were also developed. High temperature coupled with high RH aggravated the respiratory rate (RR) of broilers and this was accompanied by suppression of peening behaviour. High heat stress for 3 hours had a greater impact on birds than moderate heat stress for 6 hours. For broilers exposed to moderate heat stress, the provision of additional cup drinkers reduced the rise in CBT and the proportion of time spent in wing drooping behaviour, but enhanced SBTs suggesting increased heat dissipation.Federal University of Agriculture, Abeokuta, Ogun state, Nigeri

Investigation into an alternative approach of environmental control to enhance sensible heat transfer from broiler chickens during hot weather periods

Climatic conditions within the broiler building play an important role in the performances, health and welfare of broiler chickens. During hot weather periods, farmers in the temperate climates usually open all inlets onthe sidewall andoperate all the fans in theroof of thebroiler building to allow maximum airflow to relieve broilers of heat stress. However, the effects of this practice on the air velocity distribution in the broiler occupied zones of such type of building are not well documented. Therefore, this research work was set up to (1) investigate the impact of wide opened inlet on the airflow characteristics in the broiler occupied zones of an experimental broiler building at Harper Adams University, UK; (2) develop and evaluate the performance of a hot weather ventilation system, incorporatingan oscillation baffle, for broiler buildings; (3) examine the impact of the ventilation system on the airflow characteristics in the broiler occupied zones and the sensible heat transfer from broiler model. The results of the study indicated that the act of fully opening the inlets of broiler building during hot weather seasons did not improve the airflow in the broiler occupied zones at all measurement locations, including the sidewall area of the building. However, with the development of the hot weatherventilation system with oscillation baffle, operating at different fanfrequencies, baffle oscillation angles and baffle oscillation frequencies, there was a significant improvement in the average air velocity in the broiler occupied zones. At higher inlet turbulence, there was an increase in the sensible heat transfer from broilersin the sidewall area of the broiler building. This indicates that oscillation of inlet baffle instead of keeping it wide opened during the hot weather periods could direct moreairflow into the broiler occupied zones and relieve broiler chickens of heat stress

Broiler on-farm welfare assessment: Insights on the applicability of the transect method

Los pollos de engorde se crían en grupos de miles de aves, bajo condiciones ambientales y de manejo controladas. Sin embargo, el entorno puede deteriorarse rápidamente, especialmente hacia el final del periodo de cría, ocasionando problemas de bienestar. La posibilidad de realizar una evaluación efectiva del bienestar del pollo de engorde en condiciones de cría comercial presenta desafíos importantes debido al gran número de animales por lote. El método de los transectos ha sido sugerido como una herramienta práctica para la detección de los principales problemas de bienestar, incluyendo problemas de patas (inmóviles y cojos), enfermedades (enfermos y terminales), heridas (en cabeza, espalda y/o cola), aves pequeñas, sucias desplumadas y muertas. Las evaluaciones se realizan desplazándose a lo largo de los denominados transectos que se definen como el área delimitada entre líneas de comederos y bebederos o por la pared. Las evaluaciones se realizan utilizando la pantalla de evaluación de la aplicación móvil i-WatchBroiler a medida que el observador detecta problemas de bienestar a lo largo del recorrido del transecto. Resultados de estudios anteriores han demostrado la fiabilidad del método de transectos en lotes de pavos comerciales. Aunque este método de evaluación parece ser efectivo, es necesario realizar trabajos adicionales para probar el método de los transecto en diferentes condiciones experimentales. Por lo tanto, el objetivo de la presente Tesis Doctoral es investigar la aplicabilidad práctica y la solidez del método de los transectos para la evaluación del bienestar de pollos de engorde en granjas comerciales.El primer Capítulo de esta Tesis consiste en una revisión bibliográfica de las herramientas de ganadería de precisión utilizadas para controlar aspectos que afectan directamente al bienestar de las aves de producción, y del pollo de carne en particular. Las herramientas tecnológicas presentadas pueden indicar problemas de bienestar, salud y gestión. Estos incluyen sensores para monitoreo ambiental de la granja, movimiento de aves o parámetros fisiológicos; tecnologías de imágenes para detectar problemas de la marcha y picoteo de las plumas y tecnologías de infrarrojos para evaluar los cambios en la termorregulación y el metabolismo de las aves. Las oportunidades para una fácil recopilación y análisis de datos que ofrece el uso de las aplicaciones también abren nuevas oportunidades para un monitoreo fiable y eficiente del bienestar animal.En el segundo Capítulo, se presentan los resultados sobre la capacidad del método de los transectos para detectar los efectos de las distintas líneas genéticas del pollo de engorde, la calidad de cama y la posición de los transecto (pared vs centro), y de cómo estos efectos cambian con la edad. Se detectó un claro deterioro de la mayoría de los indicadores de bienestar con la edad de las aves. Una peor calidad de cama resultó en una mayor frecuencia de aves sucias, mientras que en los transectos de pared se observaron frecuencias más elevadas de pollos inmóviles, pequeños, enfermos, sucios y muertos. También se detectó una asociación entre el deterioro de los indicadores de bienestar y los resultados de producción recogidos en matadero. El aumento en la incidencia de enfermos y de la mortalidad en granja se asoció con un aumento de muertos a la llegada al matadero.El tercer Capítulo se centra en los efectos de incrementar la complejidad ambiental mediante la aplicación de estrategias de enriquecimiento ambiental sobre la incidencia de los indicadores de bienestar recopilados utilizando el método de los transectos y en los resultados de producción. La complejidad ambiental se refiere al número de tipos de enriquecimiento ambiental proporcionados (turba, balas de viruta de madera y cajas). Los resultados mostraron una incidencia decreciente de heridas, índice de problemas de bienestar (suma de todos los indicadores de bienestar), tasa de mortalidad, rechazos por heridas y aves pequeñas con mayor complejidad ambiental. En el mismo estudio, también se detectó una menor incidencia de problemas de patas, un menor índice de problemas de bienestar, menos rechazos debido a heridas, y una mayor tasa de crecimiento con el incremento del espacio disponible. La iluminación intermitente de 16h se relacionó con una menor incidencia de aves enfermas, heridas, y mortalidad. De manera similar a los resultados del Capítulo 2, se encontraron claras asociaciones entre los indicadores de bienestar obtenidos en granja y los resultados productivos. El aumento en la incidencia de problemas de patas, enfermedades, aves pequeñas y el índice de problemas de bienestar se asoció a un aumento en los rechazos por enfermedades, peso bajo y de rechazos totales.El cuarto Capítulo tuvo como objetivo evaluar la solidez del método de los transectos mediante la técnica de captura-recaptura de una subpoblación (80 individuos marcados individualmente) conocida de pollos de carne en condiciones comerciales. Dos observadores realizaron 4 muestreos/nave/día, recogiendo la posición de las aves detectadas. Se estimaron las tasas de detección y repetición de individuos por nave y transecto, y se determinó el efecto de la densidad, del número de transecto /nave (6 vs 8) y del momento de muestreo (mañana vs tarde). En promedio, se detectaron dos tercios de la subpoblación marcada con un 23.85% de tasa de repetición al evaluar toda la nave y 1.66% de repetición por transecto. Además se ha demostrado que se obtiene una tasa de repetición mínima si los dos transectos evaluados están separados por tres transectos. Las diferencias en el índice de distribución indican que las aves no distribuyen al azar, y por lo tanto, se deben evaluar tanto los transectos centrales como los de pared. Una evaluación representativa se puede obtener muestreando solo dos transectos de la nave de acuerdo con los resultados de bootstrapping de los datos de transectos.Por tanto se puede concluir que los resultados obtenidos mediante la aplicación del método de los transectos en la evaluación del pollo de engorde serían los esperables al probar la asociación entre la incidencia de los indicadores de bienestar y las condiciones ambientales y de manejo de la granja. Los resultados sugieren que se pueden realizar evaluaciones sólidas de bienestar mediante el muestreo de dos transectos, siendo estos uno central y otro de pared, separados por tres transectos intermedios. Los resultados obtenidos en los diferentes estudios de esta Tesis Doctoral respaldan la validez del método de los transectos que se puede utilizar como un método práctico y sólido de evaluación del bienestar en las granjas comerciales del pollo de engorde.<br /

Housing Environment and Farm Animals' Well-Being

This reprint contains articles from the Special Issue of Animals “Housing Environment and Farm Animals' Well-Being”, including original research, review, and communication related to livestock and poultry environmental management, air quality control, emissions mitigation, and assessment of animal health and well-being