Infrared thermography applied to the evaluation of metabolic heat loss of chicks fed with different energy densities

Abstract

Brazil must comply with international quality standards and animal welfare requirements in order to maintain its position as world's largest exporter of poultry meat. With the scenario of global climate change there is the forecast of occurrence of extreme events with characteristics of both excess cold and heat for several regions of the country. This study aimed to evaluate the effectiveness of using images of infrared thermography to evaluate the loss of sensible heat in young broilers fed different dietary energy levels. Twenty birds were reared in a house with appropriate brooding using infrared lamps. Birds were distributed in a completely randomized experimental into two treatments: T1 (control diet with 2950 kcal ME/kg -1 ), and T2 (high-energy diet with 3950 kcal ME/kg -1 ). Infrared thermographic images of the birds were recorded for four consecutive days. One bird was randomly chosen per treatment, and had special images taken and analyzed. Average surface temperature of the body area was calculated using the surface temperature recorded at 100 spots (50 at the front and 50 at the lateral side of the bird's body). Mean surface temperature of the flock was calculated recording 100 spots on the group of birds. Total radiant heat loss was calculated based on the average data of surface temperature. The results indicated that the young broilers fed the high-energy diet presented a metabolic energy loss equivalent to 0.64 kcal h -1 , while the birds fed with the control diet lost 2.18 kcal h -1 . This finding confirms that oil supplementation to the diet reduces bird heat loss. The infrared camera was able to record young broilers' surface temperature variation when birds were fed diets with different energy contents. INTRODUCTIONBrazil produced almost 11 million tons of chicken meat in 2009, out of which 70% was exported, making it the leading poultry exporter in the world (UBA, 2009). In order to keep this position, the Brazilian production chain must make constant innovations to meet international quality standard requirements. In addition, the world's largest chicken meat importers have set deadlines for the compliance of requirements for intensive production systems, including those related to housing environment and animal welfare.When the housing environment not within the thermoneutral zone, metabolic heat dissipation of poultry changes. The thermal tolerance of broilers varies according to age and weight. The thermal comfort zone of 1 to 7-d-old broilers is around 31-33 °C, and it is reduced to 21-23 °C when they are 35 to 42 days old, considering that air relative humidity is between 65 and 70% (Furlan & Macari, 2002

Heritability of body surface temperature in hens estimated by infrared thermography at normal or hot temperatures and genetic correlations with egg and feather quality

“…This study is the first attempt to our knowledge to estimate the heritability of body temperature measured by infrared thermography in poultry. Infrared thermal imaging has undergone major development during the past decade for application to biological research into thermal physiology in mammals (Klir and Heath, 1992) and chickens (Nääs et al, 2010;Ferreira et al, 2011). Using infrared thermography, Yahav and Giloh (2012) demonstrated that the main skin zones of heat dissipation were the head (including comb and barbs), the shank and, to a lesser extent, the wing.…”

“…Infrared thermography has in recent years become a valuable tool in veterinary and animal sciences to measure infrared body radiation to detect fluctuations in body surface temperature (Stewart et al, 2005;McCafferty, 2007;Ferreira et al, 2011). The advantage of this technique is that it is noninvasive and of remote assessment, and can measure body surface temperature with minimal manipulation of birds that can bias measurements.…”

Termografia Por Infravermelho Em Medicina Veterinária

“…Em outro estudo foi analisada a eficiência do aparelho termográfico na detecção da variação de produção de calor metabólico de pintos na fase de crescimento. Esses animais foram alimentados com diferentes densidades energéticas, de modo que foi verificado que a termografia por infravermelho identificou efetivamente a atividade metabólica dessas aves (FERREIRA et al, 2011).…”

Thermal efficiency of individual shelters for girolando calves in brazilian semi-arid regions

“…Through this, we may state that thermography is a valid tool to observe animal skin temperatures under various conditions, as a non-invasive method. According to BUSTOS MAC-LEAN (2012), D' ALTERIO et al (2011), FERREIRA et al (2011), MOURA et al (2011), NÄÄS et al (2010) and SCOLARI et al (2009, this technique has advantages over conventional methods. Moreover, ZOTTI (2010) reported that errors can be minimized by the use of such device, beyond of providing high precision and accurate records, as well as convenience for data manipulation and temperature measurements .…”