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
This study aimed to assess the yield loss caused by capybaras in rural areas of Dourados-MS, their feeding periods, crop preferences and the landscape characteristics of farms that may affect the occurrence of capybara's herds. Semi-structured interviews in 24 different farms were done during a period between April 2010 and August 2011. Field observations were held at different times of the day, and also during the night in order to record peaks of the feeding behavior in six farms. Direct counting of capybaras along with the group of animals reported as seen by the farmers during the interviews was used to estimate the size of herds. Data was analyzed using the Principal Components Analyses and the Analytic Hierarchy Process. The average number of capybaras found in a regular herd was 18.8 ± 7.90 animals. The average number of capybara herd by farms was of 1.38 ± 0.92 while the average number of capybaras by farms was 32.33 ± 27.87. Capybaras selected rice (Oryza sativa) when it was available (14.5% of devastation in 1.18% of total planted area); however, the most eaten crop was corn (Zea mays) with 38.55% of loss rate in 16.17% of the total planted area. Capybaras ate mostly in the evening and during the night. The availability of water resources in the rural area predisposed the occurrence of capybara's herds.
Egg production, infrared thermography, natural diet supplement.Submitted: September/2014 Approved: March/2015 ABSTRACT Laying hens reared under tropical conditions are usually under heat stress. Propolis is known for its pharmaceutical properties, such as increasing cell tolerance to hyperthermia, because of its antioxidants effects. This study aimed at evaluating the influence of different dietary propolis inclusion levels on the performance, egg quality, and bird surface temperature of layers. In this experiment 120 55-wk-old Isa Brown ® layers were distributed according to a completely randomized experimental design into four treatments (0, 1, 2 and 3% dietary propolis inclusion levels), with three replicates of ten birds each. Performance and egg quality parameters, and birds' surface temperature were evaluated. Egg production, egg mass, feed intake, and feed conversion ratio were influenced by the treatments. Bird surface temperature was not affected by propolis dietary inclusion. The egg yolk color changed with the treatment (p<0.05) when brightness and red and yellow concentration were considered. Evaluators noted a slight difference among treatments during the sensory analysis. The use of propolis in the hens' diet did not improve performance and worsened the eggs' quality.
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