Journal article
Sheep genotype, age and muscle type affect the expression of metabolic enzyme markers
Australian Journal of Experimental Agriculture, Vol.47(10), pp.1180-1189
2007
Abstract
The objective of this study was to determine whether genotype, age (4, 8, 14 and 22 months), sex (ewe and wether) and muscle type influence ovine (n = 587) muscle metabolic characteristics. The genotypes represented were Poll Dorsetgrowth × Border Leicester Merino, Poll Dorset growth × Merino, Poll Dorsetmuscling × Merino, Merino × Merino and Border Leicester × Merino. Between 4 and 22 months of age, myoglobin concentration within all muscles and all genotypes doubled, with the bulk of this response occurring between 4 and 8 months of age. Levels in the longissimus thoracis et lumborum (LT) and semimembranosus muscles were double those seen in the semitendinosus (ST) muscle, and Merinos had the lowest myoglobin concentrations of all genotypes. The other aerobic indicator, isocitrate dehydrogenase, had lower activity in the ST compared with the LT, was lower in 22-month-old sheep compared with all other ages, and decreased as selection for leanness increased. Both phosphofructokinase and lactate dehydrogenase activity tended to increase with age, were lower in the ST compared with the LT, and had higher activity in the Border Leicester × Merino sheep. The correlation between the percentage of total myofibre area comprising type 2X myofibres and metabolic markers was far higher for the oxidative indicators isocitrate dehydrogenase and myoglobin, which both decreased as relative area of type 2X fibres increased. However, the strongest correlations were with the relative area of type 2A myofibres, which were consistently high for both oxidative and glycolytic metabolic markers implying positive coregulation with both energy producing pathways.
Details
- Title
- Sheep genotype, age and muscle type affect the expression of metabolic enzyme markers
- Authors/Creators
- G.E. Gardner (Author/Creator) - Poultry CRCD.L. Hopkins (Author/Creator) - Poultry CRCP.L. Greenwood (Author/Creator) - Poultry CRCM.A. Cake (Author/Creator) - Poultry CRCM. Boyce (Author/Creator)D.W. Pethick (Author/Creator) - Poultry CRC
- Publication Details
- Australian Journal of Experimental Agriculture, Vol.47(10), pp.1180-1189
- Publisher
- CSIRO Publishing
- Identifiers
- 991005546326607891
- Copyright
- © CSIRO 2007.
- Murdoch Affiliation
- School of Veterinary and Biomedical Sciences
- Language
- English
- Resource Type
- Journal article
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30 Record Views
InCites Highlights
These are selected metrics from InCites Benchmarking & Analytics tool, related to this output
- Collaboration types
- Domestic collaboration
- Citation topics
- 3 Agriculture, Environment & Ecology
- 3.51 Dairy & Animal Sciences
- 3.51.206 Meat Quality
- Web Of Science research areas
- Agriculture, Multidisciplinary
- ESI research areas
- Agricultural Sciences