ABSTRACT
The objective was to investigate gene and protein expression of myosin heavy chain (MyHC) in Nellore cattle slaughtered at different weights (BW) or degrees of meat tenderness. Ninety animals with initial BW 370 ± 37 kg, 24 months of age, were slaughtered after 95 days on feed. We evaluated shear force (SF), myofibrillar fragmentation index, ribeye area, backfat thickness, marbling, color, and cooking losses. Subsequently, 24 animals were selected and divided into four contrasting groups, in which light (BW = 504.58 ± 32.36 kg) versus heavy animals (BW = 604.83 ± 42.97 kg) and animals with tender (SF = 3.88 ± 0.57 kg) versus tough meat (SF = 7.95 ± 1.04 kg) were compared. The MYH7, MYH2 and MYH1 genes were analyzed by real-time PCR. The MyHC isoforms (MyHC-I, MyHC-IIa, and MyHC-IIx) were quantified by SDS-PAGE electrophoresis. We found lower expression of MYH2 and MYH1 genes in heavy compared to light animals and a higher amount of MyHC-I isoform in the tough meat group compared to the tender meat group. Protein expression of MyHC-IIa was higher in the tender meat group. A negative correlation was found of this protein and SF (tenderness), suggesting MyHC-IIa as a biomarker of meat quality.
Subject(s)
Cattle/growth & development , Cattle/genetics , Gene Expression Regulation/physiology , Meat/standards , Myosin Heavy Chains/genetics , Animals , Muscle, Skeletal/metabolismABSTRACT
The main objectives of this study were to identify and functionally classify SNPs and indels by exome sequencing of animals of the racing line of Quarter Horses. Based on the individual genomic estimated breeding values (GEBVs) for maximum speed index (SImax) obtained for 349 animals, two groups of 20 extreme animals were formed. Of these individuals, 20 animals with high GEBVs for SImax and 19 with low GEBVs for SImax had their exons and 5' and 3' UTRs sequenced. Considering SNPs and indels, 105 182 variants were identified in the expressed regions of the Quarter Horse genome. Of these, 72 166 variants were already known and 33 016 are new variants and were deposited in a database. The analysis of the set of gene variants significantly related (Padjusted < 0.05) to extreme animals in conjunction with the predicted impact of the changes and the physiological role of protein product pointed to two candidate genes potentially related to racing performance: SLC3A1 on ECA15 and CCN6 on ECA10.
Subject(s)
Exome/genetics , Horses/physiology , INDEL Mutation/genetics , Physical Conditioning, Animal , Polymorphism, Single Nucleotide , Animals , Breeding , Horses/geneticsABSTRACT
The objective of this study was to evaluate associations between single nucleotide polymorphism (SNP) markers and carcass traits measured postmortem in Nellore cattle. Records of loin eye area (LEA) and backfat thickness (BF) from 740 males and records of hot carcass weight (HCW) from 726 males were analyzed. All of the animals were genotyped using the BovineHD BeadChip. Association analyses were performed by the restricted maximum likelihood method that considered one SNP at a time. Significant SNPs were identified on chromosomes 2 and 6 for LEA and on chromosomes 7, 1, and 2 for BF. For HCW, associations with SNPs were found on chromosomes 13, 14, and 28, in addition to genome regions that were directly related to this trait, such as the EFCAB8 and VSTM2L genes, and to bone development (RHOU). Some SNPs were located in very close proximity to genes involved in basal metabolism (BLCAP, NNAT, CTNNBL1, TGM2, and LOC100296770) and the immune system (BPI).
Subject(s)
Meat/standards , Animals , Body Weight/genetics , Cattle/genetics , Cattle/growth & development , Food Quality , Gene Frequency , Genetic Markers , Genome-Wide Association Study , Genotype , Male , Muscle, Skeletal/physiology , Polymorphism, Single Nucleotide , Subcutaneous Fat/anatomy & histologyABSTRACT
The aim of this study was to estimate genetic and phenotypic associations of growth traits with carcass and meat traits in Nellore cattle. Data from male and female animals were used for weaning weight (WW; N = 241,416), yearling weight (YW, N = 126,596), weight gain from weaning to yearling (GWY, N = 78,687), and yearling hip height (YHH, N = 90,720), respectively; 877 male animals were used for hot carcass weight (HCW) and 884 for longissimus muscle area (LMA), backfat thickness (BT), marbling score (MS), and shear force (SF). The variance components were estimated by the restricted maximum likelihood method using three-trait animal models that included WW. The model for WW included direct and maternal additive genetic, maternal permanent environmental, and residual effects as random effects; contemporary group as fixed effects; and age of dam at calving and age of animal as covariates (linear and quadratic effects). For the other traits, maternal effects and the effect of age of dam at calving were excluded from the model. Heritability ranged from 0.10 ± 0.12 (LMA) to 0.44 ± 0.007 (YW). Genetic correlations ranged from -0.40 ± 0.38 (WW x LMA) to 0.55 ± 0.10 (HCW x YW). Growth, carcass, and meat traits have sufficient genetic variability to be included as selection criteria in animal breeding programs.
Subject(s)
Genetic Association Studies , Quantitative Trait, Heritable , Red Meat , Animals , Cattle , Female , Male , PhenotypeABSTRACT
The objective of this study was to evaluate the effect of backfat thickness (BFT) on the meat quality of feedlot-finished Nellore bulls (Bos indicus). Seventy-two animals were feedlot finished for about 100 days. For this study, 24 animals were sampled according to BFT in the longissimus thoracis muscle after slaughter: 12 animals with BFT up to 3.0 mm (class BFT-3) and 12 animals with BFT > 6.0 mm (class BFT-6). Chemical (myofibrillar fragmentation index, intramuscular fat content, and unsaturated and saturated fatty acids) and physical (cold carcass weight, rib eye area, and marbling score) characteristics of the meat were evaluated. Additionally, shear force and sensory characteristics (aroma, flavor, tenderness, chewiness, and juiciness) were analyzed. Marbling score and intramuscular fat content were considered low for the two BFT classes. The mean values of the characteristics studied did not differ (P>0.05) between BFT classes, except for fatty acids, with the observation of higher unsaturated fatty acid levels in the BFT-6 class. There was no difference (P>0.05) in sensory characteristics between BFT classes. The most consistent relationship was observed between the myofibrillar fragmentation index and tenderness, measured as shear force, in animals with greater BFT (BFT-6 class) compared to animals with lower BFT (BFT-3 class), suggesting possible tenderness problems in animals with a leaner carcass. The observation of a higher concentration of unsaturated fatty acids in animals with greater BFT suggests an increase in the sensory perception of meat, especially flavor...(AU)
O objetivo deste estudo foi avaliar o efeito da espessura de gordura subcutânea (EGS) na qualidade da carne de bovinos machos Nelore (Bos indicus), inteiros, terminados em confinamento. Setenta e dois animais foram terminados em confinamento por cerca de 100 dias. Para o presente estudo, 24 animais foram amostrados de acordo com a EGS obtida no longissimus thoracis, após o abate: 12 animais com EGS até 3,0 mm (classe EGS-3) e 12 animais com EGS maior que 6,0 mm (classe EGS-6). Foram avaliadas características químicas da carne (índice de fragmentação miofibrilar, conteúdo de lipídeos intramusculares e ácidos graxos insaturados e saturados), e características físicas da carcaça (peso da carcaça resfriada, área de olho de lombo e escore de marmorização). Adicionalmente, foram avaliadas em amostras maturadas por 21 dias, a força de cisalhamento e características sensoriais (aroma, sabor, maciez, mastigabilidade e suculência). Os valores de escore de marmorização e de conteúdo de lipídeos intramusculares foram considerados baixos para ambas as classes de EGS. As médias das características avaliadas não diferiram (P>0,05) entre as classes de EGS, com exceção dos ácidos graxos, que foi superior para o insaturado na classe EGS-6. As características sensoriais não diferiram (P>0,05) entre as classes de EGS. Foi verificado relação mais consistente entre índice de fragmentação miofibrilar e maciez, medida pela força de cisalhamento, em animais com maior EGS (classe EGS-6), comparativamente a animais com menor EGS (classe EGS-3), o que sugere possível problema de maciez em animais de carcaça mais magra. A observação de maior concentração de ácidos graxos insaturados em animais com maior EGS sugere aumento da percepção sensorial da carne, especialmente do sabor...(AU)
Subject(s)
Animals , Cattle , Cattle/classification , Subcutaneous Fat/physiology , Meat , Growth and DevelopmentABSTRACT
The objective of this study was to evaluate the effect of backfat thickness (BFT) on the meat quality of feedlot-finished Nellore bulls (Bos indicus). Seventy-two animals were feedlot finished for about 100 days. For this study, 24 animals were sampled according to BFT in the longissimus thoracis muscle after slaughter: 12 animals with BFT up to 3.0 mm (class BFT-3) and 12 animals with BFT > 6.0 mm (class BFT-6). Chemical (myofibrillar fragmentation index, intramuscular fat content, and unsaturated and saturated fatty acids) and physical (cold carcass weight, rib eye area, and marbling score) characteristics of the meat were evaluated. Additionally, shear force and sensory characteristics (aroma, flavor, tenderness, chewiness, and juiciness) were analyzed. Marbling score and intramuscular fat content were considered low for the two BFT classes. The mean values of the characteristics studied did not differ (P>0.05) between BFT classes, except for fatty acids, with the observation of higher unsaturated fatty acid levels in the BFT-6 class. There was no difference (P>0.05) in sensory characteristics between BFT classes. The most consistent relationship was observed between the myofibrillar fragmentation index and tenderness, measured as shear force, in animals with greater BFT (BFT-6 class) compared to animals with lower BFT (BFT-3 class), suggesting possible tenderness problems in animals with a leaner carcass. The observation of a higher concentration of unsaturated fatty acids in animals with greater BFT suggests an increase in the sensory perception of meat, especially flavor...
O objetivo deste estudo foi avaliar o efeito da espessura de gordura subcutânea (EGS) na qualidade da carne de bovinos machos Nelore (Bos indicus), inteiros, terminados em confinamento. Setenta e dois animais foram terminados em confinamento por cerca de 100 dias. Para o presente estudo, 24 animais foram amostrados de acordo com a EGS obtida no longissimus thoracis, após o abate: 12 animais com EGS até 3,0 mm (classe EGS-3) e 12 animais com EGS maior que 6,0 mm (classe EGS-6). Foram avaliadas características químicas da carne (índice de fragmentação miofibrilar, conteúdo de lipídeos intramusculares e ácidos graxos insaturados e saturados), e características físicas da carcaça (peso da carcaça resfriada, área de olho de lombo e escore de marmorização). Adicionalmente, foram avaliadas em amostras maturadas por 21 dias, a força de cisalhamento e características sensoriais (aroma, sabor, maciez, mastigabilidade e suculência). Os valores de escore de marmorização e de conteúdo de lipídeos intramusculares foram considerados baixos para ambas as classes de EGS. As médias das características avaliadas não diferiram (P>0,05) entre as classes de EGS, com exceção dos ácidos graxos, que foi superior para o insaturado na classe EGS-6. As características sensoriais não diferiram (P>0,05) entre as classes de EGS. Foi verificado relação mais consistente entre índice de fragmentação miofibrilar e maciez, medida pela força de cisalhamento, em animais com maior EGS (classe EGS-6), comparativamente a animais com menor EGS (classe EGS-3), o que sugere possível problema de maciez em animais de carcaça mais magra. A observação de maior concentração de ácidos graxos insaturados em animais com maior EGS sugere aumento da percepção sensorial da carne, especialmente do sabor...
Subject(s)
Animals , Cattle , Cattle/classification , Meat , Subcutaneous Fat/physiology , Growth and DevelopmentABSTRACT
The objectives of this work were to study the segregation of single nucleotide polymorphisms of the calpain 1, large subunit (CAPN1) and calpastatin (CAST) genes in Nellore (Bos indicus) and Nellore xBos taurus beef cattle, as well as to evaluate their effects on meat traits. For this, 300 animals, including 114 Nellore, 67 Angus x Nellore, 44 Rubia Gallega x Nellore, 41 Canchim, 19 Brangus three-way crosses and 15 Braunvieh three-way crosses, were genotyped for the CAPN4751 [AF_248054.2:g.6545C>T (GenBank accession AF248054.2)] and CAST/DdeI [AF_159246.1:g.2959A>G (GenBank accession AF159246.1)] polymorphisms and phenotyped for Ribeye Area, Backfat Thickness, Intramuscular Fat, Shear Force (SF) and Myofibrillar Fragmentation Index (MFI). In relation to the CAPN4751 polymorphism, a frequency of 10.5% was observed for the C allele in the Nellore breed. In the total sample of studied animals, a significant association was found between genotypes and meat tenderness, assessed by SF (P = 0.005) and MFI (P = 0.008), with genotype CT being more favourable than TT. For the CAST/DdeI polymorphism, a frequency of 55.7% was found for the A allele in the Nellore breed. In the total sample, a significant association was observed between genotypes and meat tenderness - SF (P = 0.004) and MFI (P = 0.006), with genotype AA being more favourable than AG. The relationship between genotypes and aged meat tenderness in confluence with the distribution of favourable alleles shows great potential for application of the CAPN4751 and CAST/DdeI polymorphisms in the genetic improvement of the Nellore breed, whilst contributing to the validation, in this breed and in its crosses with B. taurus, of the association results previously described in the literature.
Subject(s)
Body Composition/genetics , Calcium-Binding Proteins/genetics , Calpain/genetics , Cattle/genetics , Crosses, Genetic , Meat , Polymorphism, Single Nucleotide , Alleles , Animals , Cattle/anatomy & histology , Gene Frequency , Genotype , Least-Squares AnalysisABSTRACT
Intoxicação crônica por cobre foi observada em um rebanho de 20 ovinos no município de Franca, São Paulo. Três meses após o início do arraçoamento com feno e ração concentrada peletizada para bovinos de leite, seis animais apresentaram anorexia, icterícia severa e urina marrom escura, e vieram a óbito. Diagnosticou-se doença hemolítica com base em sinais clínicos, alterações macroscópicas observadas na necropsia e observações histológicas. A necropsia todos os ovinos apresentaram icterícia severa, fígado amarelado com padrão lobular evidente e rins escuros. As principais alterações histológicas incluíram necrose hepática periacinar e nefrose hemoglobinúrica. Acúmulos de cobre foram demonstrados nos hepatócitos e macrófagos pela coloração rodamina e níveis elevados de cobre mediante espectrofotometria de absorção atômica no soro, fígado e rins de dois ovinos afetados e na ração fornecida.
Subject(s)
Animals , Anemia, Hemolytic/complications , Anemia, Hemolytic/diagnosis , Copper/toxicity , SheepABSTRACT
Intoxicação crônica por cobre foi observada em um rebanho de 20 ovinos no município de Franca, São Paulo. Três meses após o início do arraçoamento com feno e ração concentrada peletizada para bovinos de leite, seis animais apresentaram anorexia, icterícia severa e urina marrom escura, e vieram a óbito. Diagnosticou-se doença hemolítica com base em sinais clínicos, alterações macroscópicas observadas na necropsia e observações histológicas. À necropsia todos os ovinos apresentaram icterícia severa, fígado amarelado com padrão lobular evidente e rins escuros. As principais alterações histológicas incluíram necrose hepática periacinar e nefrose hemoglobinúrica. Acúmulos de cobre foram demonstrados nos hepatócitos e macrófagos pela coloração rodamina e níveis elevados de cobre mediante espectrofotometria de absorção atômica no soro, fígado e rins de dois ovinos afetados e na ração fornecida.(AU)