No abstract

It is known that PSE meat present important functional defects, such as low water holding capacity and ultimate pH, which may compromise the quality of further-processed meat products. In this study, L* (lightness), a* (redness), and b* (yellowness) values of 500 chicken breast fillets were determined using a portable colorimeter (Minolta, model CR-400) in a commercial processing plant. Fillets were considered pale when their L* was ≥49. Out of those samples, 30 fillets with normal color and 30 pale fillets were evaluated as to pH, drip loss, cooking loss, water holding capacity, shear force, and submitted to sensorial analysis. An incidence of 10.20% PSE meat was determined. Pale and normal fillets presented significantly different (p≤0.05) pH values, L* and a* values, water holding capacity, drip loss, and cooking loss, demonstrating changes in the physical properties of PSE meat. Shear force and sensorial characteristics were not different (p>0.05) between pale and normal fillets. Despite the significant differences in meat physical properties, these were not perceived by consumers in terms of tenderness, aspect, and flavor. The observed incidence of PSE may cause losses due to its low water retention capacity. INTRODUCTIONPoultry meat production has undergone many changes in the last few years. Parts are increasingly sold relative to whole carcasses. Moreover, there is an increasing number of further-processed products, such as nuggets, breaded and other ready-to-cook and ready-to-eat products, available in the market. However, the quality of these products is directly related to the quality of the meat used to prepare them.According to the Brazilian Poultry Association (União Brasileira de Avicultura -UBA, 2008), Brazilian chicken production exceeded the volumes sold in previous years both in the domestic and international markets. Exporters expect to obtain significant increase in sales, particularly as new markets are opened. One of the factors that allowed Brazil to become the largest global chicken meat exporter in terms of revenue was the increase in the sales of chicken parts and further-processed products, which have higher added value.A significant proportion of chickens is deboned for breast exports, and consequently, meat quality defects, such as PSE (pale, dry, and exudative meat), result in important losses for chicken meat industry. In addition, taking into account the increasing number of further-processed chicken meat products in the last few years, it is essential for processors to have correct information on PSE meat (Komiyama, 2006). PSE meat is a meat quality defect that affects important meat physical properties, such as water holding capacity and ultimate pH, which may reduce the quality of further processed chicken meat products (Komiyama, 2006

The present study aimed to assess the influence of adding straw bales, step platforms, and laser projectors as environmental enrichment resources on the behaviour and welfare indicators of broiler chickens (Gallus gallus domesticus). A sample of 4,000 day-old male Cobb® 500 birds was used. The experimental treatments consisted of No Environmental Enrichment (NEE)—similar to a conventional environment; and Environmental Enrichment (EE)—environment enriched with straw bales, step platforms, and laser projectors, with four replicates per treatment of 500 animals. Behavioural characteristics (ethological observation through cameras, grab test, and modified touch test) and animal welfare indicators (pododermatitis and dorsal cranial myopathy) were assessed. The birds submitted to the EE treatment exhibited greater exploratory activity and expression of behaviours associated with comfort and welfare, whereas those in the NEE group were less active. Locomotion and play fighting behaviour decreased and behaviours associated with comfort increased as age advanced. The frequencies of interaction with laser spots and birds lying around straw bales were the highest in the 1st week (P<0.01). The behaviours of pecking at straw bales (P<0.0004), using the step platforms (P = 0.0001) and being on top of straw bales (P<0.0002) gradually increased. The chickens accessed the feeding troughs the most in the period of 0800 hours (P<0.0001) and expressed the highest frequencies of behaviours associated with comfort in the 1400 hours and 1700 hours periods. The birds in the EE group were calmer in face of human presence and touch and scored higher in animal welfare indicators. Adding straw bales, step platforms, and laser projectors increased locomotion, reduced expression of fear, and improved animal welfare indicators of broiler chickens.

RESUMOO experimento foi realizado nas instalações experimentais da Faculdade de Medicina Veterinária e Zootecnia da Unesp, Campus de Botucatu e objetivou-se avaliar o efeito das dietas com milho e farelo de soja, sorgo com alto tanino e farelo de soja e sorgo com baixo tanino e farelo de soja sobre o desempenho, rendimento de carcaça e parâmetros gastrintestinais de frangos de corte. Foram utilizados 1200 pintos de corte de um dia, da linhagem Ross 308, distribuídos em 24 boxes em um delineamento experimental inteiramente casualizado em esquema fatorial 3 x 2, três dietas: 100% milho e farelo de soja, 100% sorgo com alto tanino e farelo de soja (SAT) e 100% sorgo com baixo tanino e farelo de soja (SBT) e dois sexos, com 4 repetições de 50 aves cada. O desempenho foi avaliado aos 21, 35 e 42 dias de idade e aos 42 dias de idade, uma amostra de 5 aves por repetição foi abatida para a determinação do rendimento de carcaça e das partes. Foram medidos o rendimento do peito desossado, coxa e sobrecoxa, asas, dorso e gordura abdominal. Aos 14, 21, 28, 35 e 42 dias de idade foram sacrificadas 3 aves por repetição para avaliação do desenvolvimento das vísceras e dos intestinos por meio de pesagens e medidas. Conclui-se que, ao utilizar sorgo com alto tanino (cultivar AG3002 com 1,89 g/kg) e sorgo com baixo tanino (cultivar SAARA com 0,49 g/kg) em substituição ao milho não foi encontrado efeito significativo (p>0,05) para os parâmetros analisados de desempenho e rendimento de carcaça, não ocorrendo também efeito evidente sobre a porcentagem das vísceras e intestinos e as medidas dos intestinos.Termos para indexação: Desempenho, frangos de corte, intestinos, sorgo, tanino. ABSTRACTThe experiment was carried out in the experimental facilities of Faculdade de Medicina Veterinária e Zootecnia of Unesp, Botucatu Campus and the objective was evaluate the effect of corn, sorghum with tannin and sorghum no tannin-based diets on the gastric and bowel parameters in broiler . One thousand and two hundred sexed Ross 308, one-day-old chicks were used, divided in 24 boxes in an completely randomized experimental design with factorial arrangement 3x2, three diets: 100% corn, 100% sorghum with tannin (SAT) and 100% sorghum without tannin (SBT) and two sexes, with 4 replications of 50 birds each The broiler performance was evaluate at 21, 35 and 42 days of age. At 42 days of age, a sample of 5 birds per replication was slaughtered to carcass yield determination. At 14, 21, 28, 35 and 42 days of age 3 birds per replication were slaughtered for the evaluation of guts and bowel development by means of weighing and measurements. It can be concluded that, when using sorghum with tannin (AG3002 crop with 1.89g/kg) and sorghum no tannin (SAARA crop, with 0.49g/kg) replacing corn, there was no evident effect (p>.05) on performance, carcass yield, as well as on guts and bowel percentage or on the bowel measures. INTRODUÇÃOEmbora a utilização do sorgo na alimentação de aves tenha sido muito pesquisada no Brasil nas décadas de setenta e oitenta, o ...

-The objective of this study was to evaluate the correlation between the ability to walk (gait score), incidence of femoral degeneration, tibial dyschondroplasia, valgus and varus deformity and leg symmetry of broiler chickens. Male chickens of the Cobb strain from a commercial poultry farm were utilized in this experiment. Fifty 35 and 42-day-old birds were evaluated according to the gait score and valgus or varus incidence. To assess the bilateral symmetry and the lesion score for femoral degeneration and tibial dyschondroplasia, broilers were weighed and euthanized for the removal of the femur and tibia of both legs. The lesion scores for femoral degeneration and tibial dyschondroplasia, varus or valgus deformity, bone symmetry and gait scores of the chickens were then correlated. It was found that weight, age and the incidence of femoral degeneration and tibial dyschondroplasia are not always correlated with the gait score and that only valgus deformity is more correlated.

Two experiments were carried out at the Poultry Sector of the School of Agrarian Sciences of the Federal University of Grande Dourados to evaluate the incidence of leg problems in broilers reared on two distinct types of bedding material: rice husks or wood shavings, both new and reused. In both trials, a randomized experimental design was applied in factorial arrangement (2 x 2 x 2) using two genetic strains (Cobb ® or Ross ® ); two sexes (male or female), and two litter materials (rice husks or wood shavings). In each trial 1080 one day pullets were reared equally divided in the treatments. The birds were placed in 4.5 m 2 boxes at a density of 10 birds m -2 . All birds were fed diets with equal nutritional density, and water was offered ad libitum. Feeds were divided in three phases: starter diet (1 -21 days), grower diet (22 -35 days), and finisher diet (36 -45 days). On day 45, fifty birds were randomly selected in each experiment to evaluate flock leg problems. The following parameters were analyzed: gait score, incidence of valgus and varus disorder, footpad dermatitis, femoral degeneration, tibial dyschondroplasia, and spondylolisthesis. Ambient temperature during rearing and litter caking and moisture content were recorded in four boxes per treatment. The analytical hierarchy process was used to organize the data into specific criteria. Several criteria, related to the attributes that were determinant according to the statistical analysis, were chosen in order to provide the best input to the process. Results indicated that new wood-shavings bedding was the most appropriate bedding to prevent locomotion problems, followed by new rice husks, reused wood shavings, and reused rice husks. However, when leg problems were associated to sex and genetic strain, male Ross birds strain presented less problems when reared on new rice husks, followed by new wood shavings

The aim of this study was to evaluate the effects of different litter materials on litter compaction, broiler feathering and the incidence of carcass lesions. In the experiment, 3240 one-day-old Ross ® chicks were selected by sex and distributed according to a completely randomized experimental design in a 2 x 6 factorial arrangement (two sex and six litter materials). The following litter materials were used: wood shavings, rice husks, chopped Napier grass, 50% sugar cane bagasse plus 50% wood shavings, 50% sugar cane bagasse plus 50% rice husks, and pure sugar cane bagasse. Litter compaction was weekly assessed using a penetrometer. On days 21, 35 and 42 of the experimental period, feathering on the back and legs was scored according to a 0 -10 scale. On day 42, birds were slaughtered and the presence of bruises, scratches and footpad lesions was recorded. Litter material had no effect on bird feathering. Carcass lesions (scratches, bruises and footpad lesions) were influenced by the litter material evaluated. Birds reared on sugarcane bagasse and chopped Napier grass presented more scratches, bruises and footpad lesions than the others. Dermatitis was more evident in birds reared on sugarcane bagasse, chopped Napier grass and the combination of litter materials. It was found that males presented higher incidence of dermatitis and footpad lesions than females. Each litter material presented different compaction degrees, which increased along the experimental period. Sugarcane bagasse, chopped Napier grass and the combination of bedding materials presented the highest degree of compaction, compared with wood shavings and rice husks.

-This study aimed to evaluate the relationship between the steadiness of broilers during the stance phase of locomotion, and the primary disorders of the locomotor system and gait. The experimental design was completely randomized, in a factorial arrangement (2 × 2 + 32), indicating two sexes and two genetic commercial strains, with five replications of 53 broilers each, and 32 (16 males and 16 females) indigenous chickens. Gait score and valgus and varus condition were assessed. Pictures of the birds were taken and evaluated. The broiler body was considered a spherical shape, and the centroid was calculated. From the geometric center of the body, a line was drawn perpendicularly to the sphere radius that formed an angle (ANG) with the other vertical line drawn from the centroid to the ground. The angle projected onto the ground was analyzed, and the body steadiness (EC) was estimated. At the 42nd day of growth, broilers were weighed to assess the body weight, the breast weight after slaughter, and the percentage of the breast (PB). Femoral degeneration, tibial dyschondroplasia, spondylolisthesis, and footpad dermatitis were evaluated. Fast-growing broilers presented a high prevalence of locomotor issues. The PB was not affected by sex or genetic strain. Males showed better ANG than the females, regardless of the genetic strain. More balanced EC was found in commercial broilers when compared with the indigenous chicken that stood slightly towards the back during the stance phase. A medium (in males) to high (in females) association between EC and ANG was found amongst broilers from the commercial strains in both males and females. The broilers from commercial strains presented more locomotor issues than the indigenous chicken. Commercial broiler strains show less locomotor soundness than indigenous chickens.