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Wooden breast myopathy (WB) strongly affects the poultry industry mainly in terms of consumers rejection and economical loses, due to morphological changes in broiler muscle tissue and consequently low meat quality. The aim of this study is to evaluate the histomorphometry of muscle fibers of breast fillets of broilers with severity levels of WB myopathy. The histological evaluation considered 30 samples of the pectoralis major muscle and the level of WB myopathy (ten normal fillets, ten moderate fillets, and ten severe fillets). Fillets with a severe level of WB present low average fiber number, high average fiber diameter, low percentage of fibers with diameter of less than 20 µm, low percentage of fibers with diameter between 20 and 40 µm, and high percentage of fibers with diameter between 40 and 70 µm. Fiber cross-sectional area is greater in fillets affected by moderate and severe WB. Thus, fillets with a severe level of WB damage the muscle fiber structure and contribute more severely to the degenerative processes of breast meat.

Effects of the interaction between lighting programme and dietary protein content on broiler performance and meat yield were investigated. The hypothesis was that low breast meat yield from birds managed under short day lengths could be improved by increasing dietary protein content. The treatments consisted of four lighting programmes and four dietary protein levels. They were applied to sexed broilers from one day old to 35 days old. Eight light-tight rooms each contained eight pens with 50 birds, sexes separate, in each pen. Each feed x sex treatment was replicated twice in each room, with the four lighting treatments also being replicated twice. Multiple regression analysis was used to measure responses to the three factors. There was no significant interaction between dietary protein content and lighting programme in feed intake, feed conversion efficiency, bodyweight gain, carcass chemical composition and breast meat yield. Breast meat yield was linearly related to the number of hours of light, the highest yield occurring on the longest day length. Food intake was the same on the shortest day length and the longest, yet breast meat yield was greater on the 23-hour light programme. The decreased breast meat yield in broilers given short day lengths was therefore not the consequence of a shortage of dietary protein, and this hypothesis therefore had to be rejected.

In this study, we aimed to investigate the meat quality characteristics, bioactive compound content, and antioxidant activity during refrigerated storage of breast meat of Arbor Acres broilers (carcass weight: 1.1 kg, raised for 35 D) obtained from a conventional farm (BCF, n = 30) and an animal welfare farm (BAF, n = 30) in Korea. The BCF and BAF did not differ in their proximate composition, color, water-holding capacity, creatine, creatinine, and carnosine contents. However, the shear force value was significantly higher in BAF than in BCF (P < 0.05). The 2-thiobarbituric acid reactive substance (TBARS) levels in BCF on days 7 and 9 were significantly higher than those in BAF (P < 0.001). During storage, the total volatile basic nitrogen (VBN) content of BAF was significantly lower, except on day 1. The fatty acid composition of samples was not affected by the storage period, however, saturated fatty acid and unsaturated fatty acid contents did differ among the types of farm systems (P < 0.05). Although the creatine, creatinine, and carnosine contents in BAF and BCF did not differ significantly, the carnosine and creatinine contents decreased with the increase in storage period (P < 0.05). The anserine content of BAF was significantly higher than that of BCF throughout storage. Superoxide dismutase activity was not affected by the type of farm system but was affected by storage period. Overall, BAF showed lower pH, microorganism, TBARS, and VBN values, and higher anserine contents than BCF. These findings can serve as reference data for the evaluation of chicken meat quality of broilers raised in animal welfare farm and conventional farm.

Korat chicken (KRC) is a slow-growing chicken bred in Thailand, whose meat exhibits a unique toughness. A previous study produced KRC breast meat containing high carnosine content through dietary supplementation with β-alanine or L-histidine, however, the KRC that were fed an L-histidine-supplemented diet produced meat that was significantly more tender. Herein, we performed RNA-Seq to identify candidate genes involved in the regulation of carnosine content and meat toughness. Total RNA was isolated from five female KRC breast muscles in each treatment group that KRC fed diets without supplementation, supplemented with β-alanine or L-histidine. Compared to the non-supplemented group, we identified 118 and 198 differentially expressed genes (DEGs) in the β-alanine or L-histidine supplementation groups, respectively. Genes potentially related to meat tenderness—i.e., those regulating myosin, collagen, intramuscular fat, and calpain—were upregulated (LOC107051274, ACSBG1, and CAPNS2) and downregulated (MYO7B, MYBPH, SERPINH1, and PGAM1). However, carnosine synthase gene was not identified. Functional enrichment analysis identified pathways affected by dietary supplementation, including the insulin signaling pathway (β-alanine supplementation) and the insulin resistance and adipocytokine signaling pathways (L-histidine supplementation). The FoxO signaling pathway was identified as a regulatory network for both supplementation groups. The identified genes can be used as molecular markers of meat tenderness in slow-growing chickens.

The present study was designed to investigate the role of three different light-emitting diode (LED) light color temperatures on the growth performance, carcass characteristics, and breast meat quality of broilers. In our experimental condition, 180 chicks were randomly distributed into four environmentally controlled rooms (three replicates/treatment). The experimental design consisted of four light sources: neon (Control), Neutral (Neutral LED, K = 3500–3700), Cool (Cool LED, K = 5500–6000), and Warm (Warm LED, K = 3000–2500). Upon reaching the commercial weight (3.30 ± 0.20 kg live weight), 30 birds from each group were randomly selected, and live and carcass weight were evaluated to determinate the carcass yield. Following the slaughtering, samples of hemibreast meat were collected from each group and analyzed for physical and chemical properties, fatty acids composition, and volatile compounds. Live weight and carcass weight were negatively influenced by the Warm LED, however, no significant differences were observed in carcass yield in any of the experimental conditions. Higher drip loss values were detected in breast meat samples obtained by broilers reared under Neutral and Cool LEDs. In regard to the meat fatty acids profiles, higher polyunsaturated fatty acids (PUFA) values were detected with the Warm LED, however, the ratio of PUFA/saturated fatty acids (SFA) did not change in any group. The evaluation of volatile profiles in cooked chicken meat led to the identification of 18 compounds belonging to the family of aldehydes, alcohols, ketones, and phenolic compounds, both at 0 (T0) and 7 (T7) d after the cooking. The results of the present study suggest that the LED represents an alternative technology that is cheaper and more sustainable than traditional light sources, since it allows economic savings for poultry farming without significant alterations on the production parameters or the quality of the product.

Objective This study was conducted to estimate the genetic parameters and breeding values of breast meat related traits of Pekin ducks. Selection response was also determined by using ultrasound breast muscle thickness (BMT) measurements in combination with bosom breadth (BB) and keel length (KL) values. Methods The traits analyzed were breast meat weight (BMW), body weight (BW), breast meat percentage (BMP) and the three parameters of breast meat (BB, KL, and BMT). These measurements were derived from studying 15,781 Pekin ducks selected from 10 generations based on breast meat weight. Genetic parameters and breeding value were estimated for the analysis of the breeding process. Results Estimated heritability of BMW and BMP were moderate (0.23 and 0.16, respectively), and heritability of BW was high (0.48). Other traits such as BB, KL, and BMT indicated moderate heritability ranging between 0.11 and 0.28. Significant phenotypic correlations of BMW with BW and BMP were discovered (p

Acute heat stress may affect the quality of broilers meat, however there are no reports considering thermal conditions commercially available in Brazil. In this way, the present work aimed to fill this gap of industrial relevance. Broilers of commercial strain (Cobb 500, n = 540) were randomly assigned to two thermal conditions: acute heat stress (AHS; 35°C; 75 – 85% relative humidity) and not-heat-stress (NS; 22ºC; 83 ± 6.6% relative humidity), for 2 hours prior to slaughter. The mortality rate for AHS broilers reached 37%, which was greater than 5.2% verified for NS. According to the mean values, the broiler chickens were not totally affected in the parameters of pH24h, lightness (L*), cooking loss, and shear force. However, the distributions of data show great variability in the values of pH24h, L* and water holding capacity (WHC) for AHS broilers. It is suggested that AHS broilers, at severe conditions which result in increased mortality, present breast meat with greater incidence of higher pH24h, and lower lightness and WHC values.

Objective: This study aimed at investigating white striping (WS) and wooden breast (WB) cases in breast meat collected from commercial broilers. Methods A total of 183 breast samples were collected from male Ross 308 broilers slaughtered at the age of 6 weeks (n = 100) and 7 weeks (n = 83). The breasts were subjected for meat defect inspection, meat quality determination and histology evaluation. Results Of 183, 4 breasts from 6-week-old broilers were classified as non-defective while the others exhibited the WS lesion. Among the 6-week-old birds, the defective samples from the medium size birds (carcass weight ≤ 2.5 kg) showed mild to moderate WS degree with no altered meat quality. Some of the breasts from the 6-week-old birds with carcass weight above 2.5 kg exhibited WB in accompanied with the WS condition. Besides of a reduction of protein content, increases in collagen matter and pH values in the defective samples (p

Research Areas: Agriculture ; Dairy & Animal Science The present study was intended to answer 2 scientific hypotheses: 1) the quail species has a significant influence in quail breast meat composition; 2) the wild quail's meat presents healthier composition than their farmed counterparts. An analysis of the pectoral muscles of wild and captive common quails (Coturnix coturnix) and domestic quails (Coturnix japonica domestica) was performed. The content of fatty acids (FA), amino acids, total cholesterol, and vitamin E, some basic macro- and microminerals in the pectoral muscles of the 2 species of the genus Coturnix were analyzed. Regarding the quail species influence on meat composition, Japanese Quail (JQ) revealed better lipid composition, characterized by lower saturated FA (SFA; less 3.17 g/100 g of total fatty acids), higher polyunsaturated FA contents (PUFA; more 5.5 g/100 g of total fatty acids) and healthier polyunsaturated FA/saturated FA (P/S) and n-6/n-3 ratios and TI value (1.08, 9.54 and 0.60 vs. 0.76, 12.58, and 0.75, correspondingly). The absence of differences observed on amino acids partial sums and ratios reveals equality between species on protein nutritional quality. On the other hand, Common Quail (CQ) proved to be a better source of copper (0.181 mg/100 g of meat), iron (2.757 mg/100 g of meat), manganese (0.020 mg/100 g of meat), and zinc (0.093 mg/100 g of meat) than JQ. The comparison of farmed and wild specimens within CQ, showed that wild birds presented lower total cholesterol (less 8.32 mg/g of fresh meat) and total PUFA (less 4.26 g/100 g of total fatty acids), and higher n-3 PUFA contents (more 1.53 g/100 g of total fatty acids), which contributed to healthier P/S and n-6/n-3 ratios, but worst PI (1.60, 8.08, and 113.1 vs. 0.76, 12.58, and 100.8, respectively). The wild species revealed higher alpha-tocopherol content (2.40 vs. 1.49 mu g/g of fresh meat. Differences observed on their mineral composition counterbalance each other. Under intensive production system and similar feeding and management conditions, the CQ develops better nutritional qualities than JQ. The comparison of wild and farmed species within CQ reveals more similarities than differences. Quails meat presents good nutritional quality and introduces variability to human's diet, which is much valued by consumers. info:eu-repo/semantics/publishedVersion

Summary: This study was conducted to evaluate the effect of whole corn inclusion before pelleting on performance, processing yield, and microbiome modulation of broilers from 1 to 42 d of age. One thousand male Ross 708 broilers were randomly distributed among 4 treatments, with 10 replicate pens per treatment and 25 broilers per pen. Treatments consisted of 4 levels of whole corn (0, 2.5, 5.0, and 7.5%) replacing ground corn. Feed intake and BW were determined at 14, 28, and 42 d, and feed conversion ratio (FCR) was calculated by considering the weight of the mortality. At 42 d, ileal and cecal contents were analyzed to determine intestinal microbiota. At 43 d, 10 birds per pen were processed for yield determination. Data were evaluated using the ANOVA procedure (PROC GLM), and means were separated using Tukey's honestly significant difference procedure. Inclusion of whole corn did not influence BW and feed intake (P > 0.05) until 42 d of age. However, broilers consuming diets with 2.5, 5.0, and 7.5% whole corn had lower FCR from 28 to 42 d of age (1.93, 1.95, and 1.94 vs. 2.00, P < 0.05) than in broilers fed with diets containing 0% whole corn. Broilers fed with diets containing 5% whole corn had higher breast meat yield (29.11 vs. 28.40%, P < 0.05) than broilers fed with 7.5% whole corn, but yields were similar to broilers fed with diets without whole corn. Diets with 7.5% whole corn showed a trend toward increased Faecalibacterium (P = 0.07) and decreased Lactobacillus (P = 0.08) in cecal microbiota compared with diets with 5% whole corn. The results of this experiment indicated that up to 5% whole corn can replace ground corn in broiler diets from 1 to 42 d.

Wooden breast (WB) abnormality adversely impacts the quality of chicken meat and has been linked with oxidative stress. In this study, breast samples were taken from carcasses of 7-week-old Ross 308 broilers 20-min and 24-h postmortem. Five WB and seven non-WB control samples were assigned based on palpatory hardness (non-WB = no unusual characteristics and WB = focal or diffused hardness). WB exhibited lower contents of protein and the amino acids, i.e., isoleucine, leucine and valine, lighter surface color, lower shear force, greater drip loss and altered mineral profiles (p &le, 0.05). Despite no difference in lipid oxidation, a greater degree of protein oxidation was found in the WB meat (p &le, 0.05). Absolute transcript abundances of superoxide dismutase, hypoxia inducible factor 1 alpha and pyruvate dehydrogenase kinase 1 were greater in WB (p &le, 0.05), whereas lactate dehydrogenase A expression was lower in WB (p &le, 0.05). The findings support an association between oxidative stress and the altered nutritional and technological properties of chicken meat in WB.

Simple Summary Lack of selenium (Se) is a worldwide problem which leads to an increased exposure to various diseases in animals and humans, as well as decreased productive and reproductive performance of animals. Due to the health benefits of this element, it can be supplemented to humans as multimineral containing inorganic Se and Saccharomyces cerevisiae yeast, which mainly contains selenomethionine. On the other hand, selenium-containing food products—such as selenium-rich meat—can be considered as functional foods, which can be produced easily using organic selenium. This study states that Se-enriched breast meat with good antioxidant capacity can be produced using extracted bacterial selenoprotein. Abstract Selenium (Se) is able to transform from inorganic to organic forms via many bacterial species. This feature is being considered for delivering more bioavailable selenium compounds such as selenocysteine and selenomethionine for human and animal diet. This study investigated the effects of bacterial selenoprotein versus inorganic Se on the carcass characteristics, breast meat selenium content, antioxidant status, and meat quality of broiler chickens. One hundred and eighty chicks were randomly allotted to five treatments of a basal diet supplemented with no Se, sodium selenite, Enterobacter cloacae Selenium (ADS1-Se), Klebsiella pneumoniae-Selenium (ADS2-Se), and Stenotrophomonas maltophilia-Selenium (ADS18-Se). The results showed that bacterial selenoprotein has the ability to deposit more Se in the breast meat compared to sodium selenite. Both Se sources reduced breast meat drip loss, cooking loss, shear force, and 2-thiobarbituric acid reactive substances (TBARS) significantly. It also increased total antioxidant (TAC) and glutathione peroxidase (GSH-Px) in comparison with the negative control. The highest activity of (GSH-Px), catalase (CAT), and superoxide dismutase (SOD) was found in bacterial selenoprotein. In conclusion, bacterial selenoprotein is more efficient than sodium selenite in increasing the breast meat Se deposition and oxidative capacity of broiler chickens. Therefore, it can be effectively used to produce Se-rich meat as a functional food.

International audience; Lipid content in duck meat can show a very large variation. It influences the nutritional and sensory attributes of the meat and perhaps it influences meat susceptibility to oxidation during cold storage of fresh or processed meat. By combining the duck genotype (Muscovy duck, Pekin duck and mule) and the nutritional level (ad libitum or overfed) we were able to obtain duck fillets exhibiting a large variation in lipid content and to distribute them into 3 classes (2.0 to 3.5%, 4.0 to 5.5% and 5.9 to 7.9% fat). Storage at + 4 degrees C or -20 degrees C of raw meat or at + 4 degrees C of dry-cured fillets did neither affect the colour and fatty acid composition of the meat nor its susceptibility to lipid or protein oxidation.

In the past decades, the intense selection practices carried out in order to develop fast growing and high breast-yield turkey hybrids profoundly modified the muscle physiology leading to the development of growth-related alterations and muscular abnormalities. White striations of variable thickness have been particularly observed on the ventral surface of Pectoralis major muscle belonging from heavy male turkeys since several years. However, although the effects of white striping (WS) have been extensively studied on broilers, this condition was not considered as a main quality issue by both turkey producers and meat industry. Thus, this study aimed at evaluating whether the occurrence of WS in heavy male turkeys affects the quality traits and technological properties of meat to the same extent previously observed for broilers. In two replications, 72 Pectoralis major muscles were classified as: normal (NORM), moderate WS (MOD) and severe WS (SEV) cases. The whole muscle was weighed and cut in order to assess colour, ultimate pH, water holding (drip and cooking losses) and binding (marinade uptake) capacities, NMR relaxation properties, shear force as well as proximate composition of meat. The Pectoralis major muscles affected by WS (both moderate and severe cases) exhibited a one-fifth increased weight in comparison with their NORM counterpart. However, the occurrence of WS only partially affected the proximate composition of the meat. In detail, although moisture, collagen and protein contents did not differ among the groups, if compared with NORM, higher lipid levels were found in SEV muscles, whereas MOD had intermediate values. On the other hand, both MOD and SEV exhibited lower ash content. Despite these variations in proximate composition, both water holding and binding capacities of turkey breast meat were not affected by WS. Indeed, quality traits of raw (pH, colour, cooking losses and shear force) and marinated (uptake, cooking losses and shear force) meat as well as water distribution within the muscle tissue did not differ between NORM and WS cases. Overall, if compared with broilers, WS only marginally affected quality traits of turkey breast meat. It might thus be hypothesised a diverse specie-specific physiological response to the pressure in muscle tissue induced by the selection in turkeys that, although analogously led to the occurrence of WS, results in limited effects on meat quality.

This study evaluated lysine supplementation of 4 to 42 day of age of two commercial broiler genotypes (Arbor Acres and Lohmann). Four hundred and fifty day-old chicks were sexed and randomly distributed into 60 bamboo pens each 2 m2. A starter commercial diet as a basal diet was supplemented with lysine mono-HCL in a 2x2x5 factorial arrangement with lysine levels of 0.0, 0.5, 1.0, 1.5 and 2.0 g/kg fed from 4-21 days of age, and then followed by a finisher diet fed from 22-42 days of age. Feed consumption, body weight gain and FCR were determined on weekly basis. On d 43 of experiment, 4 birds per each replicate were processed for carcass parameters. Results of the study revealed that lysine supplementation in a starter commercial diet increased significantly carcass weight (P

Chicken breast meat was injected with calcium chloride alone and in combination with lactic acid (0.01% and 0.002%, respectively). The inhibitory effects of the treatments on microbial growth were determined in the injected chicken breast meat stored at 4°C under aerobic packaging condition for 0, 3, and 7 d. Calcium chloride combined with 0.002% and 0.01% lactic acid reduced microbial counts by 0.14 and 1.08 Log CFU/g, respectively, however, calcium chloride alone was unable to inhibit microbial growth. Calcium chloride combined with 0.01% lactic acid was the most effective antimicrobial treatment and resulted in the highest initial redness value. Calcium chloride alone and combined with lactic acid suppressed changes in pH and the Hunter color values during storage. However, injection of calcium chloride and lactic acid had adverse effects on lipid oxidation and sensory characteristics. The higher TBARS values were observed in samples treated with calcium chloride and lactic acid when compared to control over the storage period. Addition of calcium chloride and lactic acid resulted in lower sensory scores for parameters tested, except odor and color, compared to control samples. Therefore, the formulation should be improved in order to overcome such defects prior to industrial application.

A study was conducted in order to investigate quality traits and sensory properties of frozen broiler breast meat pretreated with increasing concentration (from 0 to 2%) of sodium chloride (salt). Meat samples were obtained in a single major commercial processing plant from a homogenous flock of chicken broilers (Cobb strain, 44 days-old, mixed sex, average live weight of 2.55 kg). Whole breasts were collected at random immediately after chilling and fillets (P. major muscles) were deboned by hand. A total of 12 groups of fillets were subsequently salted by hand with 0.0, 0.2, 0.4, 0.5, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0% of sodium chloride, packaged in bags, quickly frozen in the processing plant and stored at -24°C for 3 months. Prior to analysis, fillets were thawed at 2-4°C for 72 h and 12 fillets per group were used to determine chemical-physical characteristics (pH, colour, and sodium chloride content), functional properties (drip loss, cooking loss on raw and minced meat, AK-shear force, TBARS analysis) and sensory traits (level of tenderness, level of juiciness and overall liking). The addition of salt determined significant modifications of overall chemico-physical traits of the meat with special regards to pH, colour, water holding capacity and texture. Increased levels of salt determined an higher pH, darker colour, superior water holding capacity (assessed by drip and cooking losses), and higher tenderness (lower AK-shear values). The maximum improvement of WHC was observed for salt level higher than 1.2%. Inclusion of salt up to 2% did not exert a negative effect on lipid peroxidation. Sensory test evidenced higher scores of overall preference of meat starting from 0.8% salt concentration; highest scores of tenderness, juiciness and overall preference in meat samples with high salt content (1.6 and 2.0% groups) were observed.

Objetivou-se avaliar diferentes níveis de lisina digestível em rações para frangos de corte de diferentes linhagens comerciais na fase de 49 a 56 dias de idade sobre o desempenho e características de carcaça. Foram utilizados 432 frangos de corte machos de 49 dias de idade, com peso médio inicial de 3560±250 g. Utilizou-se o delineamento inteiramente casualizado em arranjo fatorial 3x4, sendo que as aves, oriundas de três linhagens (Cobb 500, Hubbard Flex e Ross 308), foram distribuídas em quatro níveis de lisina digestível (0,800; 0,950; 1,100 e 1,250%), com quatro repetições de 12 aves cada. Avaliou-se o ganho de peso, o consumo de ração, a conversão alimentar, o rendimento de carcaça, o rendimento de peito, o rendimento de carne de peito e o rendimento de coxa e sobrecoxa. Não houve interação entre os níveis de lisina digestível e as linhagens comerciais de frangos de corte. Os diferentes níveis de lisina não influenciaram (p ≥ 0,05) o desempenho e rendimento de carcaça. Existem diferenças significativas entre as linhagens para consumo de ração e características de carcaça. Sendo que a linhagem Cobb 500 teve maior rendimento de peito e carne de peito (p ≤ 0,05), enquanto as linhagens Hubbard Flex e Ross 308 tiveram maior rendimento de coxa e sobrecoxa (p ≤ 0,05). This study aimed to evaluate different digestible lysine levels in diets for broilers chickens from different commercial strains, from 49 to 56 days of age, on performance and carcass characteristics. A total of 432 male broilers from 49 days old were used, with an average weight of 3560±250 g. It was used a completely randomized design in a factorial arrangement 3x4, and the birds, from three strains (Cobb 500, Hubbard Flex and Ross 308) were divided into four levels of digestible lysine (0.800, 0.950, 1.100 and 1.250%), with four replicates of 12 birds each. It was evaluated the weight gain, feed intake, feed conversion ratio, carcass yield, breast yield, breast meat yield and the yield of the thigh and drumstick. There was no interaction between lysine levels and commercial strains of broiler chickens. The different lysine levels did not influence (p ≥ 0.05) performance and carcass yield. There are significant differences between strains for feed intake and carcass characteristics. The Cobb 500 strain had higher breast yield and breast meat (p < 0.05), while the Hubbard Flex and Ross 308 strains had higher yield of the thigh and drumstick (p < 0.05). Keywords: amino acids, breast meat, performance, genotypes, carcass yield.

The aim of the present study was to determine the effects of access to a pasture on growth performance, behavioural patterns, some blood parameters and carcass yield of a slow-growing broiler genotype. A total of 210 one-day-old male chicks of Hubbard ISA Red JA were used in the experiment. At the 84th day, live weight was determined to be lower in the outdoor rearing system (P < .01). Better feed conversion ratio was found in the indoor rearing system (P < .01). The behaviour of the broilers was compared by observing the behaviour of three randomly selected marked birds on video tape. Eating, drinking, preening, spot pecking, feather pecking, walking-standing and resting-lying were monitored. Broilers from the outdoor rearing system group showed more preening, drinking, spot pecking, walk-stand and feather pecking behaviours as a result of increasing activity. Ratio of breast and thigh (carcass weight%) was higher, whereas abdominal fat was lower in the outdoor group. As a result of this study, access to a pasture improved the behaviours of broilers.

A study to determine effects of cold water and vitamin C on growth performance in 216 Anak 2000 broiler chickens was carried out during hot- dry season in the SW Nigeria. The minimum, maximum and mean temperatures during the experiment were 19.4, 35.8 and 27.6oC respectively while the relative humidity was 72.6%. The broilers, Anak 2000 at d 28 were allotted to two groups offered either ordinary water (29.5oC) or chilled water (8.0oC) for four weeks. Each group was divided into two. Each half received either 0 or 500 mg vitamin C per litre in drinking water in 2 x 2 factorial arrangement. There were 3 replicates with 18 birds per replicate. Data on daily water intake (DWI), weekly feed intake (WFI), final liveweight (FLW), weekly weight gain (WWG), total weight gain (TWG), feed conversion ratio (FCR), percentage survival (SURV), and relative weights of breast meat, liver, spleen, gizzard, drumstick, thigh, heart and wing were subjected to analysis of variance. Water temperature had no significant effect on DWI, WFI, FCR and SURV. However, offering broiler chickens cold drinking water resulted in significantly higher WWG (p

Over the past 15 yr, the European poultry processing industry has gradually increased the availability of poultry meat in a large variety of processed ready meals following what occurred a few years before in North America. This shift toward further processed products has emphasized the necessity for higher standards in poultry meat to improve sensory characteristics and functional properties. In parallel to this market change, the consciousness of the pale, soft, and exudative (PSE)-like meat issue has extensively grown. In poultry, PSE-like meat can be generally considered meat having low ultimate pH, pale color, and poor functional properties (i.e., low water-holding capacity). In the last 10 yr, some studies have been undertaken in Europe to both characterize and evaluate the overall incidence of PSE-like chicken and turkey breast meat. According to these studies, the occurrence of PSE-like meat can be up to 40% within a flock during hot climate. Several key factors have been identified and their effects have been analyzed, including genetics, season, antemortem factors, and slaughtering conditions.

Objetivou-se avaliar diferentes níveis de proteína bruta e a suplementação de aminoácidos essenciais sobre o rendimento de carcaça e a qualidade da carne de peito de codornas de corte dos 28 aos 42 dias de idade. O delineamento utilizado foi inteiramente casualizado, com cinco tratamentos (19, 21, 23, 25, 27% PB), cinco repetições e 12 aves (seis fêmeas e seis machos) cada. Aos 42 dias de idade, quatro aves de cada parcela foram abatidas e avaliadas quanto ao rendimento de carcaça quente (RCQ) e resfriada (RCF), de peito (RP), de coxa e sobrecoxa (RCS), potencial hidrogeniônico (pH), capacidade de retenção de água (CRA), perda de peso por cozimento (PPC), cor e luminosidade e maciez objetiva (MO) do músculo. Observou-se efeito dos níveis de PB em todas as variáveis, exceto para CRA e luminosidade da carne de peito. Dessa forma, conclui-se que 19% de PB e a suplementação de aminoácidos essenciais na ração de codornas de corte seja satisfatório para o rendimento de carcaça, de peito e de qualidade da carne. The objective was to evaluate different levels of crude protein and essential amino acid supplementation on carcass yield and meat quality of breast meat quails from 28 to 42 days old. The experimental design was in a completely randomized with five treatments (19, 21, 23, 25, 27% CP), five replicates and 12 birds (six females and six males) each. At 42 days of age four birds from each treatment were slaughtered and evaluated for hot carcass yield (HCY) and cooled (CCY), breast (BY), thigh and drumstick (TDY), hydrogen potential (HP), water holding capacity (WHC), weight loss by cooking (WLC), color and luminosity and objective tenderness (OT) muscle. It was observed effect of CP levels on all variables except for WHC and luminosity of the breast meat. Thus, it is concluded that 19% CP and essential amino acids supplementation in the diet of meat quails is satisfactory to the carcass, breast, and meat quality.

Dietary lysine has been shown to impact the performance of broilers, particularly with aspect of breast meat accretion and yield. There have been studies that suggest that early dietary lysine has an effect on breast meat yield in male broilers. A study was designed to evaluate starter dietary lysine (1.20 vs 1.35% of diet as achieved by the addition of L-lysine at the expense of a filler) effect on performance of female broilers from three different genetic strain crosses, and monitor subsequent effects at 41 and 56 d of age. Body weight and feed consumption were higher for birds consuming the high lysine starter diet, but feed conversions were similar when compared to the low lysine diet. Body weight and feed conversion were similar among strains. Mortality was unaffected by lysine level and strain cross. Carcass and breast meat weight, but not yields, were higher in birds fed the high lysine diet. At 56 d differences in carcass yield, abdominal fat, and breast meat yield were seen among strains, such that the strain with highest yield had the least amount of abdominal fat in terms of absolute weight and percentage. No effect on processing yields by dietary lysine was observed at any time regardless of the growing characteristics of the broilers. However, for early slaughter ages, feeding high levels of dietary lysine during the starter phase could prove to be convenient when maximum live performance or breast meat absolute values are desiredin order to maintain the commercial quality of final products.

Um experimento foi desenvolvido com o objetivo de estimar as proporções dos cortes nobres da carcaça de frangos de corte pelo modelo linear. Foram utilizados 842 frangos machos da linhagem Avian Farms, de 22 a 42 dias de idade, distribuídos num delineamento inteiramente ao acaso em esquema fatorial 3x4. Foram fornecidas rações formuladas à base de milho e farelo de soja para conter 2.900 kcal de EM e 15,43; 17,26; 19,60; e 22,60% de PB; 3.100 kcal de EM e 16,49; 18,45; 20,95; e 24,22% de PB; e 3300 kcal de EM e 17,55; 19,64; 22,30; e 25,78% de PB, totalizando doze tratamentos. Cada tratamento foi constituído por quatro repetições de 18 aves. Fortes correlações foram observadas entre o peso vivo aos 42 dias e o peso da carcaça (r = 0,958), o peso da carcaça e o peso de pernas (r = 0,991), peso de peito+osso+pele (r = 0,965) e peso de peito desossado (r = 0,950). A porcentagem de lipídio foi negativamente correlacionada com a porcentagem de umidade da carcaça (r = -0,880). A equação linear é recomendada para a predição dos componentes anatômicos da carcaça de frangos de corte. An experiment was carried out to estimate the relations between broiler carcass weight and thighs+drumsticks, breast+bone+skin, and breast meat by the linear model. Eight hundred and sixty and four male poultry of Arbor Acres strain, from 22 to 42 days of age, were assigned to a completely randomized design in 3x4factorial scheme. Corn and soybean meal based diets were prepared to contain 2900 kcal ME and 15.43; 17.26; 19.60; and 22.60% CP; 3,100 kcal ME and 16.49; 18.45; 20.95; and 24.22%CP; and 3300 kcal ME and 17.55; 19.64; 22.30; and 25.78% CP, resulting in twelve treatments. Each treatment was constituted of four replicates of 18 birds. High correlations were observed between live weight at 42 days old and carcass weight (r = 0.958), carcass weight and thighs+drumsticks (r = 0.991), breast+bone+skin (r = 0.965) and deboned breast meat weight (r = 0.950). The lipid percentage was negatively correlated to the moisture percentage (r = -0.880). The linear equation is recommended to estimate carcass anatomical components in broiler chickens.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:06:26Z No. of bitstreams: 1 S1516-35982002000700017.pdf: 189953 bytes, checksum: c07662e866f4c061f650a125033ee6cb (MD5) Made available in DSpace on 2013-08-22T19:06:26Z (GMT). No. of bitstreams: 1 S1516-35982002000700017.pdf: 189953 bytes, checksum: c07662e866f4c061f650a125033ee6cb (MD5) Previous issue date: 2002-07-01 Made available in DSpace on 2013-09-30T18:28:04Z (GMT). No. of bitstreams: 2 S1516-35982002000700017.pdf: 189953 bytes, checksum: c07662e866f4c061f650a125033ee6cb (MD5) S1516-35982002000700017.pdf.txt: 30987 bytes, checksum: 907d590e46e0efd397f9c6f88633632a (MD5) Previous issue date: 2002-07-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:40:24Z No. of bitstreams: 2 S1516-35982002000700017.pdf: 189953 bytes, checksum: c07662e866f4c061f650a125033ee6cb (MD5) S1516-35982002000700017.pdf.txt: 30987 bytes, checksum: 907d590e46e0efd397f9c6f88633632a (MD5) Made available in DSpace on 2014-05-20T13:40:24Z (GMT). No. of bitstreams: 2 S1516-35982002000700017.pdf: 189953 bytes, checksum: c07662e866f4c061f650a125033ee6cb (MD5) S1516-35982002000700017.pdf.txt: 30987 bytes, checksum: 907d590e46e0efd397f9c6f88633632a (MD5) Previous issue date: 2002-07-01 Um experimento foi realizado para avaliar o efeito de dois níveis de lisina na dieta sobre o rendimento e qualidade da carne de peito de frangos de corte. Dois mil pintos de um dia da linhagem Ross foram distribuídos em um delineamento inteiramente casualizado, em esquema fatorial 2 x 2 (dois sexos e dois níveis de lisina). As aves foram alimentadas com dietas iniciais (1 a 21 dias), crescimento (22 a 42 dias) e acabamento (43 a 49 dias), contendo 100% dos níveis de lisina recomendados pelo NRC (1994), ou 110% nas rações iniciais e de crescimento e 120% na ração de acabamento. Dessa maneira, os níveis de lisina recomendados foram de 1,10, 1,00 e 0,85% ,respectivamente, enquanto os níveis considerados altos foram de 1,21, 1,10 e 1,02%, respectivamente, nas rações iniciais, de crescimento e de acabamento. As aves foram abatidas aos 28, 35, 42 e 49 dias de idade para avaliar o rendimento e a qualidade da carne do peito. Os níveis de lisina não afetaram os valores de pH, a composição química da carne de peito e a perda de peso por cozimento. A altura, largura e o comprimento do peito apresentaram menores valores, em todas as idades, nas aves alimentadas com níveis altos de lisina. Com base nos resultados obtidos neste trabalho, conclui-se que os níveis de lisina recomendados pelo NRC (1994) são adequados para maximizar o rendimento e a qualidade do peito de frangos de corte. An experiment was conducted to evaluate the effect of dietary lysine levels and sex on breast yield and breast meat quality. Two thousand Ross day-old chicks were reared in a 2x2 randomized factorial design (two sex and two dietary lysine levels). Birds fed starter diets (1 - 21 days), growing (22 - 42 days) and finishing (42 - 49 days) with 100% of NRC (1994) lysine requirement, or 110% in the starter and growing and 120% in the finishing diets. Recommended lysine levels were 1.10, 1.00 and .85%, while high lysine levels were 1.21, 1.10 and 1.02%, respectively, for starter, growing and finishing diets. Broilers were slaughtered at 28, 35, 42 and 49 days of age for breast meat evaluation. Dietary lysine level did not affect breast meat pH, chemical composition, cooking loss and tenderness. Breast height, width and length were lower, at all ages, when broilers fed diets with high lysine levels. It was concluded that recommended NRC (1994) lysine levels are adequate to maximize breast meat yield and quality. UNESP FMVZ Concentração em Área de Nutrição e Produção Animal UNESP FMVZ Depto. de Produção e Exploração Animal Universidade Federal do Paraná (UFPR) Programa de Pós-Graduação em Zootecnia, Área de Concentração em Nutrição e Produção Animal da FMVZ-UNESP, Botucatu-SP Departamento de Produção e Exploração Animal. FMVZ/UNESP - Fazenda Lageado. Caixa Postal - 560. CEP: 18618-000

The objective of this study was to compare the characteristics that define the quality of Woorimatdag (TM) (WM, a certified meat-type commercial Korea indigenous chicken breed) and a commercial broiler breed (Ross, CB). Two hundred WM and 200 CB chickens that were 1-d-old and mixed sex were obtained from a commercial hatchery and randomly assigned to floor pens (20 chickens per pen, 3.0×2.0 m) and raised under the same environmental conditions. WM breast meat contained significantly higher crude protein and ash as well as lower crude fat than CB breast meat (p

This is the second paper in a series that reports the allometric relationships between some of the physical parts and body protein weight of commercial broiler strains reared, sexes separate, on different dietary protein levels. In this trial, four commercial broiler strains were sampled at day old and then weekly from each of three dietary protein treatments to determine the weights of the physical parts and the chemical composition of each of 936 birds. Allometric regressions were compared between strains, sexes and dietary protein levels using linear regression with groups. Whereas these regressions were similar over strains and sexes, some interactions were evident between factors, the largest differences occurring when broilers were fed differing dietary protein levels. These differences may be explained on the basis that lipid is deposited to different extents in each of the parts in response to dietary protein. Day-old breast meat and wing weights fell below the regression that best fitted the remaining observations and so were omitted from allometric analyses. The allometric regressions presented are an attempt to provide information that would enable the prediction of the weights of breast meat, thigh, drum and wing at different stages of growth of broilers whose genotype and feed composition are adequately described. Keywords: Breast meat, thigh, drum, wing, carcass yield

This paper reports the allometric relationships between some of the physical parts and body protein weight of three commercial broiler strains reared, sexes separate, on four dietary protein levels to six weeks of age. Birds were sampled at day old and then weekly from each of the treatments to determine the weights of the physical parts and the chemical composition of each of 582 birds. Allometric regressions were compared between strains, sexes and dietary protein levels using linear regression with groups. Whereas these regressions were similar over strains and sexes, some interactions were evident between factors, and differences occurred when broilers were fed differing dietary protein levels. These differences may be explained on the basis that lipid is deposited to different extents in each of the parts in response to dietary protein, although this was not tested. The allometric regressions presented are an attempt to provide information that would enable the prediction of the weights of breast meat, thigh, drum and wing at different stages of growth of broilers whose genotype and feed composition are adequately described.Keywords: Breast meat, thigh, drum, wing, carcass yield, simulation modelling

WOS: 000294933400008, The aim of this study was to investigate the influence of pre-slaughter transport duration, as a stress factor, on nutrient and fatty acid composition of broiler breast meat. The study was conducted on 48 breast muscles obtained from Ross broilers slaughtered at the average weight of 1.8 or 2.6 kg, 36 and 46 days old, respectively. Transport duration was 1.5 or 3 h. Heavier broilers transported for longer duration had the higher protein content, while lighter broilers gave similar results. Lower moisture but higher lipid content was observed for the long transported broilers. Fatty acid composition was significantly influenced by body weight and transport duration: a lower content of PUFA was obtained for heavier broilers. Ratios of PUFA/SFA was lower in heavier broilers. A decrease in MUFA and a lower n-3/n-6 ratio was evidenced in the meat from broilers transported for longer duration., Abalioglu Yem; Soya ve Tekstil Sanayi A.S, Supported by Abalioglu Yem, Soya ve Tekstil Sanayi A.S

The variation in broiler breast meat color (L*a*b*) which normally occurs during processing was evaluated using a Minolta Chroma Meter on a total of 6,997 broiler breast fillets (P. major muscles) from a total of 79 different flocks. The samples were randomly collected at 3-6 h post-mortem from the deboning line at a single major Italian processing plant. In addition, a total of 216 fillets were selected based on lightness (L*) values as being dark (L*56) and analyzed for ultimate pH, intact and ground meat cooking loss and shear value. The overall range in measured lightness (L*) was considerable and varied from 40 (dark) to 66 (pale) indicating that high breast meat color variation during processing could exist. Broiler breast meat during summer was found to be paler (+1.7 L* unit), less red (-1.0 a* unit) and less yellow (-0.7 b* unit) than breast meat samples collected during the winter confirming that the incidence of pale meat is greater during summer as indicated by non-scientific observations of plant personnel. It was also determined that paler (L*>56) breast meat is associated with lower ultimate pH and poorer water holding capacity, while dark (L*

White striping defect (appearance of white striations parallel to muscle fiber on surface of breast) is considered an emerging issue in chicken breast meat which is related to increasing growth rate of modern hybrid birds. This study was aimed at evaluating the effect of white striping on chemical composition and nutritional value of chicken breast meat. During three replications, a total of 108 Pectoralis major muscles representing three degrees of white striping (absence=normal; presence classified in 2 levels as moderate or severe) were selected to determine proximate composition (moisture, protein, lipid and collagen) as well as sarcoplasmic and myofibrillar protein profile by sodium dodecyl sulphatepolyacrylamide gel electrophoresis analysis. The results showed that both severe and moderate white-striped fillets had higher fat content (2.53 vs 1.46 vs 0.78%; Pvs 22.2 vs 22.9%; Pvs 1.37 vs 1.43%; Pvs 421.1 kJ/100g; P