Evaluation of Pelleting Mealworm (Tenebrio Molitor) Powder with Chokeberry By-product Meal To improve Duck Production and Meat Quality Traits

This study aimed to evaluate the effects of dietary supplementation pelleted Tenebrio molitor (TM) powder with chokeberry by-product (CBP) meal on duck production and meat quality traits. A total of 180 0-day-old Pekin ducks were allocated randomly between three dietary groups viz., control, Treatment 1, and Treatment 2, with three pens per group and twenty birds per pen, characterized by increasing levels of pelleted TM powder with CBP meal in concentration of 0%, 1.5%, and 3%, respectively, and reared until 42 days of age in a completely randomized design. On day 42, the ducks were sacrificed, and breast and thigh muscles were used for meat quality evaluations. Feeding pelleted TM powder with CBP meal resulted in a significant difference in final body weight, weight gain and feed conversion ratio (p<0.05). Additionally, a significant difference was observed in the pH of the breast meat samples (p<0.05). As the only significant difference between the breast and thigh meat, 1,1-diphenyl-2-picryhydrazyl radical scavenging was influenced significantly by the dietary inclusion of pelleted TM powder with CBP meal (p<0.05). However, the values of thiobarbituric acid reactive substances and meat color in both breast and thigh meat were insignificant (p>0.05) different among all groups. To conclude, the inclusion of up to 3 % of pelleted TM powder with CBP meal in the diets of ducks did improve the growth production and antioxidant characteristics effects, which could decrease TBARS and reflected by changes in 1,1-diphenyl-2- picrylhydrazyl free DPPH radical scavenging values.(AU)

Histomorphometry of muscle fibers in breast fillets of broilers with wooden breast myopathy

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.(AU)

Natural extracts marination in chicken breast fillets / Extratos naturais na marinação de filés de peito de frango

This study evaluated the effects of natural extracts on chicken breast fillet marinades regarding the physicochemical properties, oxidative stability, and the Staphylococcus aureus and Escherichia coli inhibition during 21 days of storage. Chicken breast fillets (Pectoralis major) (128 units) purchased in a local market, were used, allocated in a completely randomized block design, in a 4 x 4 factorial scheme (antioxidant x storage time), totalling 16 treatments with eight replicates. The TBARS and the pH values were not influenced by the analyzed factors. For the color results, the values of L* and b* were lower in the marinated chicken breast fillets with basil and BHT, respectively. When assessing the effect of storage time, an increase in oxidation was observed up to 21 days of storage. For pH, a quadratic decrease after storage with an increase in the pH value from the 11th day of storage was observed. In the color results, there was a linear decrease in the L* value during the storage period and in the value of b* a quadratic effect was observed with a reduction of this intensity up to 21 days of storage. In relation to the value of a*, a quadratic effect with an increase in the red intensity from the 7 days of storage was observed. For the counting of the S. aureus, the treatments presented 102 CFU/g up to 14 days, except for the basil which exceeded the limit established by the legislation at 14 days.

O objetivo deste estudo foi avaliar os efeitos de extratos naturais em marinados de filés de peito de frango sobre as propriedades físico-químicas, estabilidade oxidativa e inibição Staphylococcus aureus e Escherichia coli durante 21 dias de armazenamento. Foram utilizados 128 filés de peito de frango (Pectoralis major) adquiridos no mercado local, alocados em delineamento de blocos inteiramente casualizados em fatorial 4 x 4 (antioxidante x tempo de armazenamento), totalizando 16 tratamentos com oito repetições. Os valores de TBARS e pH não foram influenciados pelos tratamentos. Para os resultados de cor apenas os valores de L* e b* foram influenciados pelos tratamentos, sendo os menores valores encontrados no tratamento com manjericão e BHT, respectivamente. Avaliando o efeito do tempo de armazenamento observou-se aumento da oxidação até 21 dias de estocagem. Para o pH verificou-se diminuição quadrática após a estocagem com aumento no valor do pH a partir do 11º dia de armazenamento. Nos resultados de cor, verificou-se queda linear no valor L* durante o período de armazenamento e no valor de b* observou-se efeito quadrático com redução dessa intensidade até 21 dias de estocagem. Em relação ao valor de a* observou-se efeito quadrático com aumento da intensidade a partir dos sete dias de armazenamento. Para contagem de S. aureus, os tratamentos apresentaram <102 UFC/g até 14 dias, exceto o manjericão que aos 14 dias excedeu o limite estabelecido pela legislação.

Performance and meat quality of Label Rouge chickens at different slaughter ages / Parâmetros de produção e qualidade da carne de frangos Label Rouge em diferentes idades de abate

This study evaluated the performance parameters, carcass characteristics, and meat quality of Label Rouge chickens raised under an alternative system as a function of age at slaughter. The design was completely randomized with a 5×2 factorial arrangement, with slaughtering at five ages (70, 90, 120, 150, and 180 days) and two sexes. A total of 240 birds (Pescoço Pelado strain) were used, including 120 females and 120 males. Performance, carcass, physicochemical, proximate composition, and muscle fiber traits were evaluated. Rearing time and sex had significant effects on performance-related traits, with better results for males. The interaction between slaughter age and sex had a significant effect on the carcass and physicochemical parameters, which cause different responses in males and females with increasing slaughter age. For the proximate composition and muscle fiber analysis, the interaction between the parameters studied only had a significant effect on ether extract in the breast. The increase in age resulted in chickens with higher live and carcass weight at slaughter but lower performance indices. Females had lower carcass yield and greater deposition of abdominal fat. Females had lower tenderness in the drumstick and males in the breast with increasing slaughter age, and both cuts had more intense color and redness and reduced lightness starting at the slaughter age of 90 days.

O objetivo deste estudo foi avaliar os parâmetros de desempenho e as características de carcaça e qualidade da carne de frangos Label Rouge criados em sistema alternativo em função do aumento da idade de abate. O delineamento foi inteiramente casualizado (DIC) disposto em esquema fatorial (2x5), sendo dois sexos (macho e fêmea) e cinco idades de abate (70, 90, 120, 150 e 180 dias). Foram utilizadas 240 aves (Pescoço Pelado), sendo 120 fêmeas e 120 machos, sendo avaliados os parâmetros de desempenho, carcaça, físico-químicos, composição centesimal e fibra muscular. Com o aumento no tempo de produção houve efeitos dos períodos de produção e sexo em relação a variáveis de desempenho, com melhores resultados para os machos. Para os parâmetros de carcaça e físico-químicos, houve interação entre sexo e idade de abate, revelando comportamento diferenciado para machos e fêmeas com aumento da idade de abate. Para a composição centesimal e análise das fibras musculares, somente para extrato etéreo no peito foi verificado interação entre os fatores estudados. O aumento da idade proporcionou a obtenção de frangos com maiores pesos vivos e de carcaça ao abate com consequente redução dos índices de desempenho, além de menor rendimento de carcaça e maior deposição de gordura abdominal nas fêmeas. As fêmeas apresentam menor maciez na coxa e os machos no peito com aumento da idade de abate e, em ambos os cortes, ocorreu maior intensificação da cor, índice de vermelho e redução do brilho a partir de 90 dias ou em maiores idades de abate.

Performance and meat quality of Label Rouge chickens at different slaughter ages / Parâmetros de produção e qualidade da carne de frangos Label Rouge em diferentes idades de abate

ABSTRACT: This study evaluated the performance parameters, carcass characteristics, and meat quality of Label Rouge chickens raised under an alternative system as a function of age at slaughter. The design was completely randomized with a 5×2 factorial arrangement, with slaughtering at five ages (70, 90, 120, 150, and 180 days) and two sexes. A total of 240 birds (Pescoço Pelado strain) were used, including 120 females and 120 males. Performance, carcass, physicochemical, proximate composition, and muscle fiber traits were evaluated. Rearing time and sex had significant effects on performance-related traits, with better results for males. The interaction between slaughter age and sex had a significant effect on the carcass and physicochemical parameters, which cause different responses in males and females with increasing slaughter age. For the proximate composition and muscle fiber analysis, the interaction between the parameters studied only had a significant effect on ether extract in the breast. The increase in age resulted in chickens with higher live and carcass weight at slaughter but lower performance indices. Females had lower carcass yield and greater deposition of abdominal fat. Females had lower tenderness in the drumstick and males in the breast with increasing slaughter age, and both cuts had more intense color and redness and reduced lightness starting at the slaughter age of 90 days.

RESUMO: O objetivo deste estudo foi avaliar os parâmetros de desempenho e as características de carcaça e qualidade da carne de frangos Label Rouge criados em sistema alternativo em função do aumento da idade de abate. O delineamento foi inteiramente casualizado (DIC) disposto em esquema fatorial (2x5), sendo dois sexos (macho e fêmea) e cinco idades de abate (70, 90, 120, 150 e 180 dias). Foram utilizadas 240 aves (Pescoço Pelado), sendo 120 fêmeas e 120 machos, sendo avaliados os parâmetros de desempenho, carcaça, físico-químicos, composição centesimal e fibra muscular. Com o aumento no tempo de produção houve efeitos dos períodos de produção e sexo em relação a variáveis de desempenho, com melhores resultados para os machos. Para os parâmetros de carcaça e físico-químicos, houve interação entre sexo e idade de abate, revelando comportamento diferenciado para machos e fêmeas com aumento da idade de abate. Para a composição centesimal e análise das fibras musculares, somente para extrato etéreo no peito foi verificado interação entre os fatores estudados. O aumento da idade proporcionou a obtenção de frangos com maiores pesos vivos e de carcaça ao abate com consequente redução dos índices de desempenho, além de menor rendimento de carcaça e maior deposição de gordura abdominal nas fêmeas. As fêmeas apresentam menor maciez na coxa e os machos no peito com aumento da idade de abate e, em ambos os cortes, ocorreu maior intensificação da cor, índice de vermelho e redução do brilho a partir de 90 dias ou em maiores idades de abate.

Maternal instinct of imported meat direction cattle and ethology of their calves

The examination of maternal qualities in the ethology of cows and their young offspring, derived from the study on adaptability and productivity of second and third-generation Aberdeen Angus cattle imported to Kazakhstan from Canadian and European selection, is presented in this paper. The findings indicate that Canadian heifers, belonging to the second generation, displayed extended feeding behavior throughout the day, dedicating 33.2 minutes or 2.2% more time to feeding compared to their European counterparts (P < 0.001). Similar disparities between groups were observed in the duration of the ruminant process. Moreover, Canadian heifers consumed water for an additional 2 minutes or 0.6%, which can be attributed to their higher daily feed intake. The calving process of Aberdeen Angus cows generally proceeded smoothly, demonstrating a well-developed maternal instinct towards their offspring. Notably, calves born from Canadian cows exhibited greater agility and achieved the ability to stand on their feet in a shorter time, with an average duration of 41.0 ± 1.60 minutes, which was 11.7% faster than European calves. Additionally, Canadian calves displayed a shorter time to locate their mother's breast, with an average duration of 68.0 ± 7.70 minutes.(AU)

Extruded urea could replace true protein source in supplements for lambs finished in tropical pastures / A ureia extrusada pode substituir a fonte de proteína verdadeira em suplementos para cordeiros terminados em pastagens tropicais

The aim of this study was to evaluate the effects of replacing 50% of the true protein from soybean meal with extruded urea on the performance and carcass characteristics of lambs finished on pasture. Twenty lambs with initial weight of 29.9±6.2kg and 5 months of age, distributed in two treatments in blocks at random, were kept in pastures of Urochloa spp. Supplemented with 2% of body weight (BW). The treatments consisted of supplements containing soybean meal as the only true protein source (control), or extruded urea replacing 50% of soybean meal (NPN treatment). There was no effect of treatment on total supplement intake. There were differences in average daily gain (242.1 vs. 264.6g/day), slaughter weight (41.9 vs. 45.0kg) and carcass weight (18.9 vs. 20.1kg). There was no effect of the treatment on the final body condition score, hot carcass yield, carcass length, breast depth, subcutaneous fat thickness or rib eye area. The group of animals that received extruded urea showed superior carcass finishing characteristics (99.0% vs. 66.0%), maturity (22.0% vs. 0.0%), marbling (55.0% vs. 33.0%), meat texture (44.0% vs. 33.0%) and fat (66.0% vs. 22.0%). There were no significant effects on tenderness (7.5kg/f) or flesh color (L* = 33.2; a* = 16.2; b* = 8.3). There were no significant changes in the biochemical profile of the animals' blood during the experiment for both treatments. The replacement of 50% of protein from soybean meal by the extruded urea as NPN source in the supplement for lambs finished in Urochloa spp pastures provides better animal performance and qualitative characteristics of meat, without altering quantitative carcass characteristics.

Objetivou-se avaliar os efeitos da substituição de 50% da proteína verdadeira do farelo de soja por ureia extrusada sobre o desempenho e as características de carcaça de cordeiros terminados em pasto. Vinte cordeiros de 29,9+6,2kg de peso inicial e com cinco meses de idade, distribuídos em dois tratamentos em blocos ao acaso, foram mantidos em pastagens de Urochloa spp. suplementado com 2% do peso vivo (PV). Os tratamentos consistiram em suplementos contendo farelo de soja como única fonte de proteína verdadeira (controle), ou ureia extrusada em substituição a 50% do farelo de soja (tratamento NPN). Não houve efeito do tratamento na ingestão total de suplemento. Houve diferenças no ganho médio diário (242,1 vs. 264,6 g/dia), no peso ao abate (41,9 vs. 45,0kg) e no peso da carcaça (18,9 vs. 20,1kg). Não houve efeito do tratamento sobre escore de condição corporal final, rendimento de carcaça quente, comprimento de carcaça, profundidade do peito, espessura de gordura subcutânea ou área de olho de lombo. O grupo de animais que recebeu ureia extrusada apresentou características superiores de acabamento de carcaça (99,0% vs. 66,0%), maturidade (22,0% vs. 0,0%), marmoreio (55,0% vs. 33,0%), textura da carne (44,0% vs. 33,0%) e gordura (66,0% vs. 22,0%). Não houve efeitos significativos na maciez (7,5 kg/f) nem na cor da carne (L*= 33,2; a*= 16,2; b * = 8,3). Não houve mudanças significativas no perfil bioquímico do sangue dos animais durante o experimento para ambos os tratamentos. A substituição de 50% da proteína do farelo de soja pela ureia extrusada como fonte de NPN no suplemento para cordeiros terminados em pastagem de Urochloa spp. proporciona melhor desempenho animal e características qualitativas da carne, sem alterar as características quantitativas da carcaça.

Weaning and concentrate supplementationon the characteristics of carcass cuts and longissimusmuscle of Suffolk lambs finished on pasture

The aim of this study was to evaluate the influence of weaning and concentrate supplementation on the characteristics of carcass cuts and longissimusmuscle of Suffolk lambs finished ona Tifton 85 (Cynodonspp.) pasture. Weaning and concentrate supplementation strategies were evaluated in four finishing systems: i) non-weaned and non-supplemented lambs; ii) non-weaned lambs supplemented with concentrate in creep feeding;iii) weaned and non-supplemented lambs; and iv) weaned lambs supplemented with concentrate. In the systems with weaning, lambs were weaned at 46 ± 6 days of age. In the systems with supplementation, the concentrate was offered daily at 2% of lambs body weight. Weaning led to a decrease, whereas supplementation led to an increase in carcass cut weights. Supplemented lambs had lower yields of neck and uncovered ribs, and higher yields of breast + flank and loin. The characteristics of loin eye and fat thicknessover the longissimusmuscle presented lower values in weaned lambs and higher values in supplemented lambs. Keeping lambs with their dams and offering concentrate supplementation until slaughter are strategies recommended to obtain heavier cuts with increased muscularity and fat content.(AU)

Partially Dehulled Sunflower Seeds in Diets for Grazing Chickens: Effect in Meat Quality

The effect of including partially dehulled sunflower seeds in the diet of grazing chickens in meat quality was evaluated. Two hundred and forty, one-day-old, Ross 308 chickens were used, randomly distributed into four treatments with six replicates of 10 birds each. Seventy-two birds were slaughtered at seven weeks of age, 18 per treatment, extracting the Pectoralis major muscle to analyze meat quality. The treatments were completely randomized in a 2x2 factorial arrangement, where type of rearing (confinement or grazing) and diet (base diet or base diet substituting 10% soybean meal for partially dehulled sunflower seeds) were the independent variables. The grazing chickens spent 8 hours a day in a white clover (Trifolium repens) paddock. Including sunflower seeds improved (p<0.05) the color and crude protein (CP) in breast meat (p<0.05), while grazing increased (p<0.05) CP, dry mater (DM), and shear force (SF), and the percentage of breast fat decreased (p<0.05) by up to 50%. Additionally, grazing increased (p<0.05) saturated fatty acids (SFA) and reduced (p<0.05) lipid oxidation by up to 50%. Partially replacing soybean meal with partially dehulled sunflower seeds in the diet of grazing chickens with white clover improves the physicochemical characteristics and nutritional quality of the breast meat; it also decreases lipid oxidation, extending the shelf life of the meat.(AU)

Diets with Ganoderma lucidum Mushroom Powder and Zinc-Bacitracin on Growth Performance, Carcass Traits, Lymphoid Organ Weights and Intestinal Characteristics in Broilers

In order to evaluate the effect of diets with Ganoderma lucidum mushroom powder and zinc-bacitracin on growth performance, carcass traits, lymphoid organ weights, and intestinal characteristics in broilers, a total of 600 one-day-old unsexed broilers from Cobb 500 MV × Cobb 500 FF genotype was analyzed for 28 days, following a completely randomized design with three dietary treatments, five replicates and 40 birds per replicate. The dietary treatments consisted of a basal diet (BD) without additives (T0) and the dietary inclusion of 2.5 g/kg of Ganoderma lucidum (T1) and 350 mg/kg of zinc bacitracin antibiotic (T2). The experimental groups did not change (p>0.05) the performance of the broilers. However, G. lucidum powder increased (p≤0.05) the carcass and breast yields (p≤0.05) and decreased the abdominal fat and liver yields (p≤0.05), although with no notable differences with the antibiotic group for the latter organ (liver) (p>0.05). Both additives (G. lucidum and antibiotic) increased breast meat moisture, protein, and redness; however, these treatments reduced L* (lightness), and the zinc-bacitracin reduced breast yellowness (p≤0.05). Likewise, this medicinal mushroom (G. lucidum) increased the relative weight of bursa of Fabricius and the morphometry of the small intestine (p≤0.05), although with no changes for other immune and digestive organs or for the content of cecal lactic acid bacteria (p>0.05). The dietary inclusion with 2.5 g/kg of Ganoderma lucidum powder is recommended to improve breast yield, protein, and colorimetry without affecting performance and cecal traits of fast-growing broilers.(AU)

Diets with Ganoderma lucidum Mushroom Powder and Zinc-Bacitracin on Growth Performance, Carcass Traits, Lymphoid Organ Weights and Intestinal Characteristics in Broilers

In order to evaluate the effect of diets with Ganoderma lucidum mushroom powder and zinc-bacitracin on growth performance, carcass traits, lymphoid organ weights, and intestinal characteristics in broilers, a total of 600 one-day-old unsexed broilers from Cobb 500 MV × Cobb 500 FF genotype was analyzed for 28 days, following a completely randomized design with three dietary treatments, five replicates and 40 birds per replicate. The dietary treatments consisted of a basal diet (BD) without additives (T0) and the dietary inclusion of 2.5 g/kg of Ganoderma lucidum (T1) and 350 mg/kg of zinc bacitracin antibiotic (T2). The experimental groups did not change (p>0.05) the performance of the broilers. However, G. lucidum powder increased (p≤0.05) the carcass and breast yields (p≤0.05) and decreased the abdominal fat and liver yields (p≤0.05), although with no notable differences with the antibiotic group for the latter organ (liver) (p>0.05). Both additives (G. lucidum and antibiotic) increased breast meat moisture, protein, and redness; however, these treatments reduced L* (lightness), and the zinc-bacitracin reduced breast yellowness (p≤0.05). Likewise, this medicinal mushroom (G. lucidum) increased the relative weight of bursa of Fabricius and the morphometry of the small intestine (p≤0.05), although with no changes for other immune and digestive organs or for the content of cecal lactic acid bacteria (p>0.05). The dietary inclusion with 2.5 g/kg of Ganoderma lucidum powder is recommended to improve breast yield, protein, and colorimetry without affecting performance and cecal traits of fast-growing broilers.

Comparative Study of Egg and Meat Quality of Guinea Fowl under Different tropical regions: A Review

Guinea fowl have several advantages over chickens. These birds are highly valued for their meat and eggs, particularly in tropical regions. They are currently in many parts of the world. Recently, the demand for guinea fowl meat has increased because it is considered a high-quality protein source. In addition, their eggs are delicious and considerably better than those of chickens. Guinea fowl eggs are valued for their thick shells, and longer shelf life, and it has premium prices compared with commercial and indigenous chickens. Chicken eggs have been well studied for egg and meat quality. However, such information isn't so sufficiently documented in other poultry species. Despite the interest in guinea fowl production, it is vital to take cognizance of the fact that there is a lack of information on the production and quality of guinea fowl products, in contrast to commercial chickens. Therefore, the present review aims to assess the egg and meat quality of Guinea fowl in different tropical regions. The main results of the current study showed that the external egg quality characteristics, mainly (egg weight, shell percentage, and shell thickness), and internal egg quality traits, mainly (albumen weight, haugh unit, yolk height, and yolk color) of Guinea fowl differed under different tropical regions. Concerning carcass characteristics, a clear difference was observed in dressing percentage and breast percentage of Guinea fowl in various tropical areas. A similar trend was observed for the meat color.(AU)

Gender, lineage, and age on muscle morphometry traits and meat tenderness of free-range chickens / Associação de fatores de produção e de morfometria muscular sobre a maciez da carne de frangos caipiras

This study assessed whether the meat tenderness of broilers raised in a free-range system varies by sex, lineage, and age at the time of slaughter. Physicochemical parameters were measured to adequately assess breast and thigh muscle morphometry, including shear force (SF), muscle fibre diameter (MD), histological connective tissue (HCT) content, and total and soluble collagen contents (TCC and SCC, respectively). The experiment was conducted with a completely randomized design using two lineages (Pescoço Pelado and Paraíso Pedrês), with specimens of both sexes raised in a free-range system. Randomly selected broilers were slaughtered at 65, 75, 85, and 95 days old. A total of 192 birds were analysed. SF values correlated positively with age. The highest SF values were measured in thighs of the Pescoço Pelado lineage. Age also showed a positive correlation with MD and HCT content of the breast regardless of lineage. Gender did not have any significant correlation with physical parameters; although, higher values were measured in thighs of the Paraíso Pedrês than in those of the Pescoço Pelado lineage. There were no significant differences among treatments regarding the SCC and TCC of thighs and breasts. Principal component analysis (PCA) revealed relationships between SF and the rest of the measured attributes. PCA showed that age was positively correlated with the SF, MD, and HCT content of thighs and breasts. In contrast, SCC and TCC had negative correlations. The greatest breast and thigh MD values were associated with the least tender meat. Thus, age at the time of slaughter proved to be the most significant parameter impacting the physical characteristics of muscle morphometry and meat tenderness of breasts and thighs of broilers raised in a free-range system.

Objetivou-se com este estudo avaliar os fatores relacionados a maciez da carne de frangos criados em sistema alternativo. Para o experimento foi avaliado a força de cisalhamento, diâmetro das fibras musculares do peito e da coxa, conteúdo de tecido conjuntivo através de histologia e teor de colágeno solúvel e total. O experimento foi executado em delineamento inteiramente casualizado (DIC) com uso de duas linhagens (Pescoço Pelado e Paraíso Pedrês) de ambos os sexos (macho e fêmea) e abatidos em quatro idades (65, 75, 85 e 95 dias), criados em sistema alternativo, sendo utilizado um total de 192 aves. Para força de cisalhamento (FC), ocorreu aumento nos valores em ambos os cortes em função da idade de abate e houve interação entre linhagem e sexo, com as maiores médias para os machos da linhagem Pescoço Pelado e diferença entre sexo para Paraíso Pedrês. A idade de abate influenciou o diâmetro das fibras musculares e o conteúdo de tecido conjuntivo do peito e da coxa, havendo aumento linear destes parâmetros em função da idade ao abate. O sexo não afetou o diâmetro das fibras musculares da coxa, enquanto na linhagem Paraíso Pedrês foram verificadas maiores médias em relação à Pescoço Pelado. A análise de componentes principais demonstrou a relação entre a força de cisalhamento e as demais variáveis analisadas. Assim, o aumento do diâmetro das fibras musculares do peito e da coxa também está relacionado à redução da maciez da carne de frangos caipiras, conjuntamente com o aumento da quantidade de tecido conjuntivo, teor de colágeno total e redução de sua solubilidade.

Predictive Equations of Carcass Characteristics and Primal Cut Weights of Native Mexican Guajolotes Using Body Measurements

This study was conducted to develop predictive equations for carcass characteristics and primal cut weights of native Mexican guajolotes using body measurements (BM). For this study, a total of 36 male guajolotes (Meleagris gallopavogallopavo), aged 6 to 10 months, and mean slaughter body weight (SBW) of 4543.14 ± 656.60 g, were used. The birds were kept under traditional extensive conditions. ThefollowingBMswererecorded24 h before slaughter: thoracicperimeter (TP), body circumference (BC), body length (BL), wing length (WL), keel length (KL), shank length (SL) and shank diameter (SD). After slaughter, hot carcass weight (HCW), cold carcass weight (CCW), hot dressing percentage (HDP), cold dressing percentage (CDP), organs and viscera weight (VIS) and abdominal fat weight (AFW) were recorded. The carcasses were dissected in to five primal cut (breast, thigh, drumstick, back and wing). The SBW and BMs showed moderate to high positive correlations (p<0.01; 0.34≤r<0.97) with carcass characteristics and primal cut weights. In the equations generated to predict HCW, CCW, HDP, CDP, VIS and AFW, the R2 ranged from 0.40 to 0.96, and the predictor variables were SBW, KL, BC, WL and SL. Regarding the equations developed to predict the primal cut weights, R2 ranged from 0.58 to 0.91. In these models, SBW, BC, SD, WL and KL explained most of the observed variation. The prediction equations obtained in the study had moderate to high accuracy; therefore, they can be used by researchers, technicians and poultry producers to obtain information on the carcass composition of native Mexican guajolotes.(AU)

Dietary supplementation of Agaricus bisporus stalk meal on growth performance, carcass and organ traits, meat quality, cecum mesophilic aerobic bacteria counts and intestinal histology in broiler chickens / Efeitos da suplementação dietética de farelo de caule de Agaricus bisporus no desempenho de crescimento, características de carcaça e órgãos, qualidade da carne, contagem de bactérias aeróbias mesófilas cecais e histologia intestinal em frangos de corte

Effects of dietary Agaricus bisporus mixture or stalk or cap on growth performance, carcass components and some meat quality parameters, mesophilic aerobic bacterial counts, and intestinal histomorphology in broiler chickens were investigated. Two hundred and forty one-day-old male Ross 308 broiler chickens were divided into 4 experimental groups with 4 replicates, each including 15 birds. Chickens were fed with basal diet (C), mushroom mixture (MM, 10 g stalk+10 g cap/kg diet), mushroom stalk (MS, 20 g/kg diet) and mushroom cap (MC, 20 g/kg diet). Feed conversion ratio (FCR) was improved (P < 0.01) by dietary MS while feed intake (FI) decreased (P < 0.01) in all treatment groups compared to control. However, body weight gain (BWG) was decreased (P < 0.01) by MC inclusion. Mushroom supplemented groups had higher (P < 0.05) mesophilic aerobic bacteria in the cecum. MS inclusion increased villus height to crypt depth ratio in the jejunum (P < 0.01) and villus height in the ileum (P < 0.01) and jejunum (P < 0.05). MC increased (P < 0.01) crypt depth in the jejunum. There were no statistical differences among groups for carcass components (P > 0.05). The L* values were decreased (P < 0.01) in thigh meat but increased (P < 0.01) in breast meat by mushroom inclusion. The a* values were decreased (P < 0.01) and b* values were increased (P < 0.05) in both thigh and breast meat with mushroom addition to diet. The obtained results indicated that A. bisporus stalk meal at an inclusion level of 20 g/kg of diet had favourable effects on growth performance with higher feed efficiency, improved intestinal morphology with higher villus height and increased meat quality of broiler chickens.

Foram investigados os efeitos da mistura dietética de Agaricus bisporus ou talo ou tampa sobre o desempenho de crescimento, componentes da carcaça e alguns parâmetros de qualidade da carne, contagens de bactérias aeróbias mesofílicas e histomorfologia intestinal em frangos de corte. Duzentos e quarenta frangos de corte Ross 308 de um dia de idade foram divididos em quatro grupos experimentais com quatro repetições, cada um incluindo 15 aves. Galinhas alimentadas com dieta basal (C), mistura de cogumelos (MM, 10 g caule + 10 g cap / kg de dieta), caule de cogumelo (MS, 20 g / kg dieta) e cogumelo (MC, 20 g / kg dieta). A taxa de conversão alimentar (FCR) foi melhorada (P < 0.01) por MS dietético enquanto o consumo de ração (FI) diminuiu (P < 0.01) em todos os grupos de tratamento em comparação com o controle. No entanto, o ganho de peso corporal (BWG) foi diminuído (P < 0.01) pela inclusão de MC. Os grupos suplementados com cogumelos apresentaram maiores (P < 0.05) bactérias aeróbias mesofílicas no ceco. A inclusão de MS aumentou a proporção entre a largura das vilosidades e a profundidade da cripta no jejuno (P < 0.01) e o comprimento das vilosidades no íleo (P < 0.01) e jejuno (P < 0.05). MC aumentou (P < 0.01) a profundidade de cripta no jejuno. Não houve diferença estatística entre os grupos nos componentes da carcaça (P > 0.05). Os valores L * diminuíram (P < 0.01) na carne da coxa, mas aumentaram (P < 0.01) na carne de peito com a inclusão de cogumelos. Os valores de a* diminuíram (P < 0.01) e os valores de b* aumentaram (P < 0.05) em ambas as coxas e peitos pela adição de cogumelos à dieta. Os resultados obtidos indicaram que a farinha de colmo de A. bisporus com um nível de inclusão de 20 g / kg de dieta teve efeitos favoráveis no desempenho do crescimento com maior eficiência alimentar, melhorou a morfologia intestinal com maior comprimento de vilosidade e aumentou a qualidade da carne de frangos de corte.

Cassava residues in the diet of slow-growing broilers / Resíduos de mandioca na dieta de frangos de crescimento lento

Cassava by-products are abundant and largely unused in familiy agro-industries in the Amazon region, where slow-growing broilers are commonly raised. Thus the incorporation of cassava by-products in broiler feed may provide starch enrichment for better zootechnical performance. We evaluated the use of cassava residues instead of corn in the diet of slow-growing broilers. We determined the chemical composition of cassava scrapings (CS) and cassava starch residue (CSR), and tested the digestibility of the residues in 192 broilers and three treatments: inclusion of 30 g kg-1 CS or CSR and a control without residue, with eight replicates of eight broilers each. Digestibility was assessed through collection of total excreta from 19 to 22 days of age. Apparent and corrected metabolizable energy, and apparent digestibility coefficients of dry matter, crude protein and crude energy were significantly higher for CSR than CS. Therefore, only CSR was used in a performance experiment using 324 broilers 30 to 90 days old, distributed in four treatments (0; 6.8; 13.4 and 20 g kg-1 CSR in feed) with nine replicates of nine broilers each. There was no significant difference among treatments in weight gain, feed intake, yield of carcass, breast and viscera, meat color, luminosity, pH, shear force, cooking-weight loss and drip loss. As there was a significant reduction in feed conversion and thigh and drumstick yield for 20 g kg-1, we suggest the incorporation of CSR up to 13.4 g kg-1.(AU)

Subprodutos da mandioca são abundantes e pouco utilizados nas agroindústrias familiares na Amazônia, onde é comum a criação de frangos de corte de crescimento lento. Portanto, a incorporação de subprodutos de mandioca na alimentação destes frangos pode proporcionar enriquecimento de amido para melhor desempenho zootécnico. Avaliamos a utilização de resíduos da mandioca na alimentação de frangos de crescimento lento em substituição ao milho. Determinamos a composição química da raspa de mandioca (RM) e do resíduo de amido de mandioca (RAM), e testamos a digestibilidade dos resíduos utilizando 192 frangos e três tratamentos: inclusão de 30 g kg-1 RM ou RAM e um controle sem mandioca, com oito repetições de oito frangos cada. Digestibilidade foi determinada por coleta de excretas totais dos 19 aos 22 dias de idade. Energia metabolizável aparente e corrigida e os coeficientes de digestibilidade aparente da matéria seca, proteína bruta e energia bruta foram significativamente maiores para RAM que RM. Assim, apenas RAM foi usado em um experimento de desempenho com 324 frangos de 30 a 90 dias de idade e quatro tratamentos (0; 6,8; 13,4 e 20 g kg-1 RAM na ração), com nove repetições de nove frangos cada. Os tratamentos não diferiram significativamente em ganho de peso, consumo de ração, rendimento de carcaça, peito e vísceras, cor da carne, luminosidade, pH, força de cisalhamento, e perda de peso por cozimento e gotejamento. Como houve redução significativa na conversão alimentar e no rendimento de coxa e sobrecoxa com 20 g kg-1, sugerimos o uso de RAM até 13,4 g kg -1.(AU)

Performance, meat quality, and lipidemia of meat-type quails fed with diets containing essential oils / Desempenho, qualidade da carne e lipidemia de codornas de corte alimentadas com rações contendo óleos essenciais

This study evaluated the effect of essential oil (ESOL) of Mentha piperita and Melaleuca alternifolia on meat-type quails. To examine performance, a completely randomized design was used, with four treatments and eight repetitions each, using seven birds per repetition. To assess lipidemia, a completely randomized design in a 4 × 2 factorial scheme was used, with four treatments and two collection conditions using eight repetitions and one bird per repetition. Weight gain, feed intake, feed conversion, carcass yield, cholesterol, high-density lipoporteins, triglycerides, pH, and brightness of quail breast meat were assessed. The data were analyzed for homoscedasticity and normality, and the means were subjected to analysis of variance. Adding M. piperita and M. alternifolia ESOL to the diets of meat-type quails can improve performance, carcass yield, and meat quality characteristics, comparable to the use of performance-enhancing antibiotics. The use of zinc bacitracin, M. piperita, and M. alternifolia under different collection conditions did not increase the serum levels of low-density and very low-density lipoproteins. The variation coefficients measured after 12 hours of fasting were 86% lower than without fasting.

Objetivou-se com este estudo avaliar o efeito do uso dos óleos essenciais (OLES) de Mentha piperita e Melaleuca alternifolia em codornas de corte. Para o estudo do desempenho foi utilizado o delineamento inteiramente ao acaso, com quatrotratamentos e oito repetições, sendo sete aves por repetição. Para o estudo da lipidemia utilizou-se o delineamento inteiramente casualizado em esquema fatorial: 4x2, consistindo em quatro tratamentos e duas condições de coleta, com oito repetições, sendo uma ave por repetição. As variáveis analisadas foram: ganho de peso, consumo ração, conversão alimentar, rendimento de carcaça, colesterol, HDL, triglicerídeos, pH, capacidade de retenção de água, perda de peso por cozimento, luminosidade na carne do peito de codornas. Os dados obtidos foram analisados quanto à homocedasticidade e normalidade, as médias foram submetidas à análise de variância. O uso de OLES de M. piperita e M. alternifolia na dieta de codornas de corte pode proporcionar desempenhos zootécnicos, rendimentos de carcaça e características de qualidade da carne comparáveis ao uso de antibióticos melhoradores de desempenho. A redução no nível de colesterol HDL foi notada nas aves tratadas com Bacitracina de zinco e com os OLES de M. piperita e M. alternifolia, em 8,12; 16,52 e 3,36% respectivamente. O uso da Bacitracina de zinco, da M. piperita e da M. alternifolia associado às diferentes condições de coleta não aumentaram os valores séricos de LDL, VLDL. Os coeficientes de variação aferidos na condição "após 12 horas de jejum" apresentaram-se 86% inferiores à condição "sem jejum".

Performance of Turkeys in Enrichment Environment with Perches and Outdoor Access under Tropical Conditions

Heat stress compromises turkey's productivity and increase mortality mainly in the final stages of growth. This study evaluated the effect of perches and its interaction with outdoor access on turkey performance in high environment temperature humidity index (THI). Turkeys were reared in 1.75 × 5 m indoor floor pens and were fed with a standard commercial diet, offered ad libitum according to the productive phase. All poults were housed indoors until 62 d of age. A free-range area for a replicate of 8.75 m2, with natural shadow, was available from 07:00 to 19:00 h. Final density was 10.33 ± 0.22 kg/m2. The treatments were a combination of a factorial arrangement (2 × 2) with or without perches and, with or without access to the outdoors. From 10:00 and 19:00 THI was above critical level of comfort (heat stress). In indoors turkeys, feed intake (FI) decreased, and water intake increased, panting was observed, and had a significantly lower final body weight (BW) and FI than turkeys allowed outdoors (p<0.05). Perch availability decreased final BW and FI (p<0.05). Differences in weight of breast meat, wings, or thighs between treatments were negligible. In conclusion turkeys with outdoor access from 62 d of age had better performance.(AU)

Weaning and concentrate supplementation on the characteristics of carcass cuts and longissimus muscle of Suffolk lambs finished on pasture

The aim of this study was to evaluate the influence of weaning and concentrate supplementation on the characteristics of carcass cuts and longissimus muscle of Suffolk lambs finished on a Tifton 85 (Cynodon spp.) pasture. Weaning and concentrate supplementation strategies were evaluated in four finishing systems: i) non-weaned and non-supplemented lambs; ii) non-weaned lambs supplemented with concentrate in creep feeding; iii) weaned and non-supplemented lambs; and iv) weaned lambs supplemented with concentrate. In the systems with weaning, lambs were weaned at 46 ± 6 days of age. In the systems with supplementation, the concentrate was offered daily at 2% of lambs' body weight. Weaning led to a decrease, whereas supplementation led to an increase in carcass cut weights. Supplemented lambs had lower yields of neck and uncovered ribs, and higher yields of breast + flank and loin. The characteristics of loin eye and fat thickness over the longissimus muscle presented lower values in weaned lambs and higher values in supplemented lambs. Keeping lambs with their dams and offering concentrate supplementation until slaughter are strategies recommended to obtain heavier cuts with increased muscularity and fat content.(AU)

Response of Broiler Chicks to Dietary L-Leucine Supplementation in the Starter Period

ABSTRACT This experiment was conducted to investigate the effects of leucine (Leu) supplementation on performance and carcass traits of broilers along with the re-evaluation of standardized ileal digestible (SID) Leu requirement of broiler chicks on days 0-14. Birds were fed seven experimental diets with SID Leu levels of 16.3 (basal), 17.3, 18.3, 19.3, 20.3, 21.3, and 22.3 g/kg. Some 280 male broiler chicks were randomly assigned to the seven dietary treatments in a completely randomized design with five replicates. Dietary SID Leu levels had significant effects on body weight gain(BWG), feed conversion ratio(FCR), carcass, and breast percentages. BWG increased (p 0.05) when the broilers fed diets with 18.3 to 21.3 g/kg SID Leu compared to the basal diet. FCR decreased (p 0.05) by dietary SID Leu levels of 18.3 to 21.3 g/kg in comparison with the basal diet. Carcass yield increased (p 0.05) by SID Leu levels of 19.3 to 21.3 g/kg. Breast percentage increased (p 0.01) when the broilers received diets with 18.3 to 22.3 g/kg SID Leu and the highest value obtained by the SID Leu level of 21.3 g/kg. Abdominal fat decreased linearly by Leu supplementation (p 0.01). Regression analysis indicated the SID Leu requirement of 18.67, 18.88, and 19.85 g/kg for BWG, FCR, and breast meat yield, respectively. It can be concluded that broiler performance characteristics, especially breast yield, improve by Leu supplementation. Based on the results, the Leu requirement of modern broilers has increased dramatically due to genetic selection for a higher growth rate.