Behavior and performance of broiler strains reared under semi-intensive system with shaded areas

The matter of animal welfare has led to studies in order to evaluate alternative rearing systems for livestock in order to improve well-being. The semi-intensive system is an alternative method of rearing broilers in which the birds are kept in a poultry house and have free access to a pasture area during the day. It is known that ambient conditions may directly affect the behavior of birds reared in the semi-intensive system. Therefore, this research evaluated the behavior of four broiler strains reared under a semi-intensive system with a shaded area (provided by a black plastic screen - 50%) and the bioclimatic characteristics of this environment when compared with the non-shaded pasture. Thirty-five birds were reared in pens with 4.5 m² and 35 m² of pasture. Ambient variables were measured throughout the day to calculate the indexes of thermal comfort (BGHI and enthalpy). Data was analyzed in a 4 x 2 factorial (4 strains and 2 rearing environments) with 2 repetitions, in order to establish the rate of bird permanence in the pasture. There was an improvement in the ambient conditions of the shaded pasture in the hottest hours of the day (from 10:00 to 14:00 h), i.e., there was a reduction in the mean values of BGHI (approximately 26%) and enthalpy (36%). As a consequence, there was an increase in the rate of permanence in this environment if compared with the non-shaded pasture. Three out of four evaluated strains showed better adaptability to the semi-intensive rearing system

Environmental and physiological variables during the catching of broilers

The objective of this study was to determine the critical points of the operation of broiler catching for transport to the processing plant from animal and operational perspectives. During catching, chickens, environmental variables (temperature and relative humidity) were constantly monitored to determine the Enthalpy Comfort Index (IEC). Also, the physiological variable rectal temperature (RT) was monitored as an indicator of stress suffered by the birds during this handling procedure. Bird welfare were evaluated by analyzing their behavior. The bag method was effective to prevent the struggling of birds while being taken from the broiler house to the transport truck, reducing physical injuries and losses during catching

Performance and carcass characteristics of free-range broiler chickens fed diets containing alternative feedstuffs

The present study was carried out to evaluate the effects of alternative feedstuffs as partial substitutes of corn and soybean in free-range broiler diets on performance, carcass yield and technical-economic viability. A total of 400 Pescoço Pelado broilers were distributed in a completely randomized experimental design (CRD), with four treatments (treatment 1:Control; treatment 2: 10% rice bran inclusion; treatment 3: 10% ground cassava leaves; and treatment 4: 10% ground lead tree hay) with four replicates per treatment. Each replicate consisted of a group of 25 birds per paddock, separated per sex. Initial weight (IW), final weight (FW), body weight (BW), daily weight gain (DWG), feed intake (FI) and feed conversion ratio (FCR) were evaluated. Carcass, cuts (breast, thigh, drumstick, back, neck, leg and wings), abdominal fat and giblets (gizzard, heart and liver) yields were determined. The technical-economic viability of each treatment was assessed by determining the cost of feed per kg body weight, economic efficiency index and cost. The highest final weights were obtained with the use of rice bran. Rice bran and cassava leaves promoted higher carcass yield, as well as lower back and abdominal fat yields. The use of cassava leaves showed better economic efficiency among the treatments with alternative feedstuffs. The use of alternative feedstuffs at 10% inclusion in substitution of corn and soybean meal did not not result in major changes in performance and carcass parameters, and economic efficiency, and therefore, their use is recommended when the availability or the price of key ingredients, such as soybean meal and corn, increase