Estudos multivariados em ruminantes do efeito da energia sobre a qualidade da carne e dos parâmetros sanguíneos sobre o consumo alimentar residual
Carregando...
Data
2022-01-06
Autores
Cruz, Antonio Ariclezio Carlos
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
RESUMO: A eficiência alimentar em bovinos de corte se caracteriza como um importante campo investigativo da nutrição animal. Diversos métodos têm sido desenvolvidos ao longo dos anos buscando agilidade e redução de custos para identificar animais mais eficientes, porém os resultados têm sido inconsistentes. Adicionalmente, tem sido desenvolvido o interesse pelo conhecimento de como se dá o uso efeito dos constituintes dietéticos sobre a qualidade da carcaça e da carne ovina, mas ainda falta clareza para explicar a relação desses fatores. Com base nisso, foram desenvolvidos dois estudos. O primeiro estudo objetivou avaliar a associação dos parâmetros sanguíneos (constituintes hormonais, metabólicos e hematológicos) com o consumo alimentar residual em bovinos de corte por meio de uma abordagem meta-analítica, enquanto que o segundo estudo buscou avaliar a relação dos níveis de energia metabolizável com as características de carcaça e qualidade da carne ovina por meio de uma análise de componentes principais (ACP). No primeiro estudo foram utilizados um total de 16 artigos publicados. Os bovinos com baixo consumo alimentar residual (BCAR) apresentaram mais células vermelhas (desvio padrão da média; DPM = + 1,206), creatinina (DPM = +0,419) e hematócrito (DPM = + 0,863) no sangue quando comparados aos bovinos com alto consumo alimentar residual (ACAR). Os animais com BCAR apresentaram maior eficiência alimentar (ganho: consumo; DPM = + 0,867), menor consumo de matéria seca (DPM = -0,952 kg / d) e menor taxa de conversão alimentar (DPM = -0,368) do que animais com ACAR. Maiores níveis de creatinina, células vermelhas e hematócrito no sangue estão associados aos bovinos com baixo BCAR. No segundo estudo foram inclusas 121 médias oriundas de 23 artigos publicados. Foram utilizados como variáveis categóricas três níveis de energia metabolizável da dieta. As características de carcaça incluídas neste estudo foram comprimento de carcaça, perda por cozimento, área de olho de lombo, espessura de gordura subcutânea, rendimento de carcaça. As medidas utilizadas estudas sobre a qualidade da carne foram as medidas de pH da carne mensurado 0,0h (pH0) e 24h pós-abate (pH24), matéria seca, extrato etéreo da carne e força de cisalhamento. Os dois primeiros componentes explicaram 81,51% da variância dos dados. As variáveis mais importantes no primeiro componente principal foram matéria seca da carne, perda por cozimento e peso corporal final, enquanto no segundo componente principal foram as variáveis rendimento de carcaça, extrato etéreo e força de cisalhamento. O baixo nível de energia foi negativamente associado as variáveis de peso corporal final e força de cisalhamento. O alto nível da energia apresentou relação positiva com o extrato etéreo da carne e perda por cozimento, mas negativa com a força de cisalhamento. Isso indica que o aumento de energia até 3,27 Mcal de EM/kg de MS na dieta de ovinos aumenta a quantidade de extrato etéreo da carne e perda por cozimento. O aumento da energia da dieta elevar o teor de extrato etéreo na carne e reduz a força e isso implica em maior facilidade para quebra dos tecidos musculares. Estudos futuros podem utilizar dos achados desta ACP para melhor entendimento dos mecanismos que envolvem a energia da dieta e qualidade de carne e carcaça ovina.
ABSTRACT: Feed efficiency in beef cattle is characterized as an important investigative field of animal nutrition. Several methods have been developed over the years seeking agility and cost reduction to identify more efficient animals, but the results have been inconsistent. Additionally, there is interest in the knowledge of how the use of dietary constituents on carcass and sheep meat quality has been developed, but there is still a lack of clarity to explain the relationship of these factors. Based on this, two studies were developed. The first study aimed to evaluate the association of blood parameters (hormonal, metabolic and hematological constituents) with residual feed intake in beef cattle through a meta-analytic approach, while the second study aimed to evaluate the relationship between metabolizable energy levels with carcass characteristics and sheep meat quality through a principal component analysis (PCA). In the first study, a total of 16 published articles were used. Both studies were carried out with the R program, version R-3.6.3. Beef cattle with low residual feed intake (LRFI) had more red blood cells (standard deviation of the mean; DPM = + 1.206), creatinine (DPM = +0.419) and hematocrit (DPM = + 0.863) in the blood when compared to beef cattle with high residual feed (HRFI). Animals with LRFI showed higher feed efficiency (gain: intake; DPM = + 0.867), lower dry matter intake (DPM = -0.952 kg / d) and lower feed conversion rate (DPM = -0.368) than animals with LRFI. Higher levels of creatinine, red blood cells and hematocrit in the blood are associated with cattle with low BCAR. In the second study, 121 means from 23 published articles were included. Three levels of metabolizable energy in the diet were used as categorical variables. The carcass traits included in this study were carcass length, cooking loss, loin eye area, back fat thickness, carcass yield. The measurements used to study meat quality were of the meat pH measured at 0.0h (pH0) and 24h post-slaughter (pH24), dry matter, meat, ether extract, and shear force. The first two components explained 81.51% of the data variance. The most important variables in the first principal component were meat dry matter, cooking loss and final body weight, while in the second principal component were the variables carcass yield, ether extract, and shear force. The low energy level was negatively associated with final body weight and shear force variables. The higher energy level showed a positive relationship with the ether extract of the meat and cooking loss, but a negative relationship with the shear force. This indicates the increasing energy up to 3.27 Mcal EM/kg DM in the sheep diet increases the amount of meat ether extract and cooking loss. The increase in dietary energy increases the content of ether extract in the meat and reduces strength and this implies greater ease for muscle tissue breakdown. Future studies may use the findings of this PCA to better understand the mechanisms that involve dietary energy and sheep meat and carcass quality.
ABSTRACT: Feed efficiency in beef cattle is characterized as an important investigative field of animal nutrition. Several methods have been developed over the years seeking agility and cost reduction to identify more efficient animals, but the results have been inconsistent. Additionally, there is interest in the knowledge of how the use of dietary constituents on carcass and sheep meat quality has been developed, but there is still a lack of clarity to explain the relationship of these factors. Based on this, two studies were developed. The first study aimed to evaluate the association of blood parameters (hormonal, metabolic and hematological constituents) with residual feed intake in beef cattle through a meta-analytic approach, while the second study aimed to evaluate the relationship between metabolizable energy levels with carcass characteristics and sheep meat quality through a principal component analysis (PCA). In the first study, a total of 16 published articles were used. Both studies were carried out with the R program, version R-3.6.3. Beef cattle with low residual feed intake (LRFI) had more red blood cells (standard deviation of the mean; DPM = + 1.206), creatinine (DPM = +0.419) and hematocrit (DPM = + 0.863) in the blood when compared to beef cattle with high residual feed (HRFI). Animals with LRFI showed higher feed efficiency (gain: intake; DPM = + 0.867), lower dry matter intake (DPM = -0.952 kg / d) and lower feed conversion rate (DPM = -0.368) than animals with LRFI. Higher levels of creatinine, red blood cells and hematocrit in the blood are associated with cattle with low BCAR. In the second study, 121 means from 23 published articles were included. Three levels of metabolizable energy in the diet were used as categorical variables. The carcass traits included in this study were carcass length, cooking loss, loin eye area, back fat thickness, carcass yield. The measurements used to study meat quality were of the meat pH measured at 0.0h (pH0) and 24h post-slaughter (pH24), dry matter, meat, ether extract, and shear force. The first two components explained 81.51% of the data variance. The most important variables in the first principal component were meat dry matter, cooking loss and final body weight, while in the second principal component were the variables carcass yield, ether extract, and shear force. The low energy level was negatively associated with final body weight and shear force variables. The higher energy level showed a positive relationship with the ether extract of the meat and cooking loss, but a negative relationship with the shear force. This indicates the increasing energy up to 3.27 Mcal EM/kg DM in the sheep diet increases the amount of meat ether extract and cooking loss. The increase in dietary energy increases the content of ether extract in the meat and reduces strength and this implies greater ease for muscle tissue breakdown. Future studies may use the findings of this PCA to better understand the mechanisms that involve dietary energy and sheep meat and carcass quality.
Descrição
Palavras-chave
Creatinina, Eficiência alimentar, Hematócrito, Sanguíneos