A qualidade de carcaça é a busca constante da indústria avícola. A preocupação com qualidade da c... more A qualidade de carcaça é a busca constante da indústria avícola. A preocupação com qualidade da carne é mundial, estimulando pesquisas e revisões neste segmento. A influência dos diversos fatores tem sido pesquisada no intuito de proporcionar qualidade ao produto. O frango de corte atual é submetido a desafios cada vez maiores ao longo da criação. A intensificação da produção têm levado à dificuldade de alojamento e manejo nos aviários. O aumento da densidade populacional influencia diretamente a qualidade da cama e compromete o produto final, pois favorece o aparecimento de lesões na carcaça. O manejo pré-abate influencia na carcaça de frangos; o tempo de jejum, a apanha, o transporte e o tempo de descanso no abatedouro devem ser bem estudados e calculados com precisão para minimizar os prejuízos que podem ser causados nessa fase final de criação. A composição e o rendimento de carcaça refletem na qualidade final do produto, sendo interessante para a indústria avícola uma menor quantidade de gordura na carcaça além de peso corporal e rendimento satisfatórios no momento de abate. Os parâmetros de qualidade da carcaça de frango devem ser pesquisados para, futuramente, serem estabelecidos critérios de qualidade para carne de frango. O desafio científico nessa área continua sendo a otimização das carcaças de frango, de forma que atenda à necessidade da indústria, do mercado e do consumidor, ou seja, produtividade, inocuidade e qualidade do produto.The quality of the carcass is the constant search of the poultry industry. There is a worldwide concern about the quality of the meat which stimulates researches in this aspect. The influence of the various factors has been researched in order to give the product some quality. The broiler chicken has been subjected to many demandings during the reating. The intensification of the product has caused some difficulties in storing and dealing with the product in the batteries.The increase of the number of broilers in the battery system has a great influence in the quality of the litter and has an impact in the final product, because it can cause some lesions on the carcass. The handling before slaughtering influences the chicken carcass: the fast period, the capture, the transportation and the resting period in the slaughterhouse should be very well evaluated to avoid problems at this last satage of the rearing. The final quality of products depends on how profitable it can be. It is also advisable for the poultry industry to have a product with less quantity of fat as well as satisfatory profit and bodily weight during the slaughter. The quality of the broiler carcass should be researched so that there will be good criteria of the quality of this meat in the future. The scientific challenge in this area is to define how well the broiler carcass can be used in order to supply the industy’s, market’s and customer’s needs, i.e. productivity, and innocuos system and the quality of the products
Ninety six Cobb male broilers from 21 to 31 days of age were fed including short chain fatty acid... more Ninety six Cobb male broilers from 21 to 31 days of age were fed including short chain fatty acids (SCFA) and different level of calcium. Calcium (Ca), phosphorus (P), balance, dry, organic and mineral matter metabolizability, crude energy and crude protein metabolizability, tibia ash percentage and animal performance were measured. Experimental diets were assigned in a 5x4 factorial arrangement (without acids, formic acid, acetic acid, propionic acid and butyric acid) x (0.40, 0.59, 0.78 and 0.97% of Ca) in a randomized completely design. Increasing Ca levels affected positively and in a quadratic form Ca and P balance and the best levels were estimated at 0,87% and 0,75% of Ca dietary, respectively and affected linearly dry, organic matter metabolizability and tibia ash percentage. However, the efficiency of Ca retention was decreased quadratically with the increase of Ca level. The SCFA did not show detectable effects on the studied responses, and no interaction with dietary leve...
ABSTRACT A total of 1,248 one-day-old male Cobb chicks were used to evaluate the effect of differ... more ABSTRACT A total of 1,248 one-day-old male Cobb chicks were used to evaluate the effect of different sources and levels of dietary zinc on the humoral immune response, zinc concentration in the tibia and carcass, footpad integrity, and performance. The birds were exposed to immunological (infectious bronchitis vaccine in the hatchery), nutritional (250 ppm of Cu in the diet) and environmental (reused litter sprayed daily with water; 1 to 21 d) challenges. The diets consisted of different levels of zinc from an organic source (10, 20, or 40 ppm of chelate Zn-HMTBa/ Mintrex Zn; Novus International Inc.), an inorganic source (10, 20, 40, or 100 ppm of zinc sulfate), and a negative control without zinc (0 ppm of Zn). The birds were immunized with 0.2 mg of BSA at 28 d and blood was collected at 41 d to measure antigen-specific antibody titer. Antibody titer, Zn concentration in the carcass, and performance (feed intake, BW gain, and feed conversion) were not affected by levels or sources of Zn. The absence of supplementary zinc in the diets significantly decreased its concentration in the tibia ash. Using 10 or 20 ppm of Zn from an organic source decreased the incidence of footpad lesions compared with the same levels of the inorganic source. It was concluded that both sources of Zn may be supplemented individually in broiler chicken diets, even in levels below 100 ppm, with no effect in carcass Zn concentration, performance, and humoral immunity, under the conditions tested. However, to keep footpad integrity, an organic source of Zn seems to be more efficient.
ABSTRACT Two experiments were performed, in male and female broilers separately, to evaluate the ... more ABSTRACT Two experiments were performed, in male and female broilers separately, to evaluate the effect of early feed restriction on the composition, gain, and efficiency of nutrients retention by comparative slaughter. Treatments were applied from 8 to 16 d age as follows: without feed restriction [standard feed (SF) ad libitum]; quantity restriction (80% ad libitum consumption of SF); time restriction (SF offered throughout 8 h/d); and quality restriction (SF diluted with 10% kaolin and 10% rice hulls containing 80% of the limiting nutrients). The broilers were raised in pens and 6 replications/treatments were used. The composition and body gain of DM, CP, and EE, and efficiency of protein and energy retention were evaluated. Time restriction was considered the most severe, mainly in males that showed less protein gain at 42 d age. Proportional body gain of EE was higher than that of CP in the refeeding period in the quantity and time restricted broilers and no improvement in the protein retention efficiency was observed in those birds previously restricted. The possibility that feed restriction decreases carcass fat was not observed.
ABSTRACT Two experiments were performed, with male and female broilers separately, to evaluate th... more ABSTRACT Two experiments were performed, with male and female broilers separately, to evaluate the effect of early feed restriction on performance, carcass, organs, breast, legs, and back weights, and breast meat quality. Treatments were applied from 8 to 16 d of age as follows: without feed restriction [T1; standard feed (SF) ad libitum]; quantity restriction (T2; 80% ad libitum consumption of SF); time restriction (T3; SF offered throughout 8 h/d); and quality restriction (T4; SF with 80% of the limiting nutrients). Birds from both sexes submitted to T2 or T3 had lower BW at the end of the restriction period, however, they were able to reach the same BW at 42 d when compared to T1. Quality restriction did not reduce initial growth because birds compensated for the dilution by increasing feed intake. Organ weights recovered more quickly than the other fractions. Females on T3 recovered BW earlier than males. Quantity restriction allowed the full recovery of breast weight at 35 d, whereas T3 only achieved that at 42 d. Restriction programs did not have any effect on weight loss due to thawing, cooking, shear force, or lipid oxidation on the breast meat. Early restriction programs either by T2 or T3 can be used as a method for controlling growth rate in broilers without any damage to performance and meat quality at 42 d of age.
ABSTRACT An experiment was conducted with broiler chickens from 1 to 36 d of age to test the effe... more ABSTRACT An experiment was conducted with broiler chickens from 1 to 36 d of age to test the effect of 30, 65, or 100 mg/kg of vitamin E in the diets of birds either vaccinated against coccidiosis (VaCC) or not vaccinated. All birds were vaccinated against Newcastle disease to verify the antibody titers generated by the different treatments. Performance and immunological parameters were evaluated. There was a significant interaction between VaCC and vitamin E level: VaCC birds consuming 65 mg/kg of vitamin E showed better BW gain for the total experimental period, lower values for the heterophil: lymphocyte ratio, and greater antibody titers for Newcastle disease. In the initial period, VaCC birds showed lower BW gain than nonvaccinated birds, but VaCC birds achieved the same performance for the total period. Vaccination against coccidiosis resulted in lower absolute and relative bursa weights and bursa diameters, but also lower lymphocyte bursa depletion or less damage in bursal lymphocytes. Vitamin E had no effect on these parameters. In addition, blood analysis was not affected by vitamin E, but VaCC birds showed lower hematocrit and hemoglobin values and higher leukocyte and lymphocyte values. The 65 mg/kg level of vitamin E positively affected performance and improved the humoral immune response, mainly for immunologically challenged birds.
A qualidade de carcaça é a busca constante da indústria avícola. A preocupação com qualidade da c... more A qualidade de carcaça é a busca constante da indústria avícola. A preocupação com qualidade da carne é mundial, estimulando pesquisas e revisões neste segmento. A influência dos diversos fatores tem sido pesquisada no intuito de proporcionar qualidade ao produto. O frango de corte atual é submetido a desafios cada vez maiores ao longo da criação. A intensificação da produção têm levado à dificuldade de alojamento e manejo nos aviários. O aumento da densidade populacional influencia diretamente a qualidade da cama e compromete o produto final, pois favorece o aparecimento de lesões na carcaça. O manejo pré-abate influencia na carcaça de frangos; o tempo de jejum, a apanha, o transporte e o tempo de descanso no abatedouro devem ser bem estudados e calculados com precisão para minimizar os prejuízos que podem ser causados nessa fase final de criação. A composição e o rendimento de carcaça refletem na qualidade final do produto, sendo interessante para a indústria avícola uma menor quantidade de gordura na carcaça além de peso corporal e rendimento satisfatórios no momento de abate. Os parâmetros de qualidade da carcaça de frango devem ser pesquisados para, futuramente, serem estabelecidos critérios de qualidade para carne de frango. O desafio científico nessa área continua sendo a otimização das carcaças de frango, de forma que atenda à necessidade da indústria, do mercado e do consumidor, ou seja, produtividade, inocuidade e qualidade do produto.The quality of the carcass is the constant search of the poultry industry. There is a worldwide concern about the quality of the meat which stimulates researches in this aspect. The influence of the various factors has been researched in order to give the product some quality. The broiler chicken has been subjected to many demandings during the reating. The intensification of the product has caused some difficulties in storing and dealing with the product in the batteries.The increase of the number of broilers in the battery system has a great influence in the quality of the litter and has an impact in the final product, because it can cause some lesions on the carcass. The handling before slaughtering influences the chicken carcass: the fast period, the capture, the transportation and the resting period in the slaughterhouse should be very well evaluated to avoid problems at this last satage of the rearing. The final quality of products depends on how profitable it can be. It is also advisable for the poultry industry to have a product with less quantity of fat as well as satisfatory profit and bodily weight during the slaughter. The quality of the broiler carcass should be researched so that there will be good criteria of the quality of this meat in the future. The scientific challenge in this area is to define how well the broiler carcass can be used in order to supply the industy’s, market’s and customer’s needs, i.e. productivity, and innocuos system and the quality of the products
Ninety six Cobb male broilers from 21 to 31 days of age were fed including short chain fatty acid... more Ninety six Cobb male broilers from 21 to 31 days of age were fed including short chain fatty acids (SCFA) and different level of calcium. Calcium (Ca), phosphorus (P), balance, dry, organic and mineral matter metabolizability, crude energy and crude protein metabolizability, tibia ash percentage and animal performance were measured. Experimental diets were assigned in a 5x4 factorial arrangement (without acids, formic acid, acetic acid, propionic acid and butyric acid) x (0.40, 0.59, 0.78 and 0.97% of Ca) in a randomized completely design. Increasing Ca levels affected positively and in a quadratic form Ca and P balance and the best levels were estimated at 0,87% and 0,75% of Ca dietary, respectively and affected linearly dry, organic matter metabolizability and tibia ash percentage. However, the efficiency of Ca retention was decreased quadratically with the increase of Ca level. The SCFA did not show detectable effects on the studied responses, and no interaction with dietary leve...
ABSTRACT A total of 1,248 one-day-old male Cobb chicks were used to evaluate the effect of differ... more ABSTRACT A total of 1,248 one-day-old male Cobb chicks were used to evaluate the effect of different sources and levels of dietary zinc on the humoral immune response, zinc concentration in the tibia and carcass, footpad integrity, and performance. The birds were exposed to immunological (infectious bronchitis vaccine in the hatchery), nutritional (250 ppm of Cu in the diet) and environmental (reused litter sprayed daily with water; 1 to 21 d) challenges. The diets consisted of different levels of zinc from an organic source (10, 20, or 40 ppm of chelate Zn-HMTBa/ Mintrex Zn; Novus International Inc.), an inorganic source (10, 20, 40, or 100 ppm of zinc sulfate), and a negative control without zinc (0 ppm of Zn). The birds were immunized with 0.2 mg of BSA at 28 d and blood was collected at 41 d to measure antigen-specific antibody titer. Antibody titer, Zn concentration in the carcass, and performance (feed intake, BW gain, and feed conversion) were not affected by levels or sources of Zn. The absence of supplementary zinc in the diets significantly decreased its concentration in the tibia ash. Using 10 or 20 ppm of Zn from an organic source decreased the incidence of footpad lesions compared with the same levels of the inorganic source. It was concluded that both sources of Zn may be supplemented individually in broiler chicken diets, even in levels below 100 ppm, with no effect in carcass Zn concentration, performance, and humoral immunity, under the conditions tested. However, to keep footpad integrity, an organic source of Zn seems to be more efficient.
ABSTRACT Two experiments were performed, in male and female broilers separately, to evaluate the ... more ABSTRACT Two experiments were performed, in male and female broilers separately, to evaluate the effect of early feed restriction on the composition, gain, and efficiency of nutrients retention by comparative slaughter. Treatments were applied from 8 to 16 d age as follows: without feed restriction [standard feed (SF) ad libitum]; quantity restriction (80% ad libitum consumption of SF); time restriction (SF offered throughout 8 h/d); and quality restriction (SF diluted with 10% kaolin and 10% rice hulls containing 80% of the limiting nutrients). The broilers were raised in pens and 6 replications/treatments were used. The composition and body gain of DM, CP, and EE, and efficiency of protein and energy retention were evaluated. Time restriction was considered the most severe, mainly in males that showed less protein gain at 42 d age. Proportional body gain of EE was higher than that of CP in the refeeding period in the quantity and time restricted broilers and no improvement in the protein retention efficiency was observed in those birds previously restricted. The possibility that feed restriction decreases carcass fat was not observed.
ABSTRACT Two experiments were performed, with male and female broilers separately, to evaluate th... more ABSTRACT Two experiments were performed, with male and female broilers separately, to evaluate the effect of early feed restriction on performance, carcass, organs, breast, legs, and back weights, and breast meat quality. Treatments were applied from 8 to 16 d of age as follows: without feed restriction [T1; standard feed (SF) ad libitum]; quantity restriction (T2; 80% ad libitum consumption of SF); time restriction (T3; SF offered throughout 8 h/d); and quality restriction (T4; SF with 80% of the limiting nutrients). Birds from both sexes submitted to T2 or T3 had lower BW at the end of the restriction period, however, they were able to reach the same BW at 42 d when compared to T1. Quality restriction did not reduce initial growth because birds compensated for the dilution by increasing feed intake. Organ weights recovered more quickly than the other fractions. Females on T3 recovered BW earlier than males. Quantity restriction allowed the full recovery of breast weight at 35 d, whereas T3 only achieved that at 42 d. Restriction programs did not have any effect on weight loss due to thawing, cooking, shear force, or lipid oxidation on the breast meat. Early restriction programs either by T2 or T3 can be used as a method for controlling growth rate in broilers without any damage to performance and meat quality at 42 d of age.
ABSTRACT An experiment was conducted with broiler chickens from 1 to 36 d of age to test the effe... more ABSTRACT An experiment was conducted with broiler chickens from 1 to 36 d of age to test the effect of 30, 65, or 100 mg/kg of vitamin E in the diets of birds either vaccinated against coccidiosis (VaCC) or not vaccinated. All birds were vaccinated against Newcastle disease to verify the antibody titers generated by the different treatments. Performance and immunological parameters were evaluated. There was a significant interaction between VaCC and vitamin E level: VaCC birds consuming 65 mg/kg of vitamin E showed better BW gain for the total experimental period, lower values for the heterophil: lymphocyte ratio, and greater antibody titers for Newcastle disease. In the initial period, VaCC birds showed lower BW gain than nonvaccinated birds, but VaCC birds achieved the same performance for the total period. Vaccination against coccidiosis resulted in lower absolute and relative bursa weights and bursa diameters, but also lower lymphocyte bursa depletion or less damage in bursal lymphocytes. Vitamin E had no effect on these parameters. In addition, blood analysis was not affected by vitamin E, but VaCC birds showed lower hematocrit and hemoglobin values and higher leukocyte and lymphocyte values. The 65 mg/kg level of vitamin E positively affected performance and improved the humoral immune response, mainly for immunologically challenged birds.
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