Muscle characteristics in Thoroughbreds of different ages and sexes.
Abstract: Muscle biopsies were taken from the middle gluteal muscle in 163 healthy Thoroughbreds aged one to six years. The horses were separated according to sex and divided into four different age groups (one, two, three and four to six years). Muscle biopsies were analysed for fibre type (I, IIA and IIB), and the enzyme activities of citrate synthase, 3-OH-acyl-CoA dehydrogenase, lactate dehydrogenase and hexokinase were measured. The percentage of Type I fibres of all horses increased with age, irrespective of sex (from 9 to 16 per cent). The percentage of Type IIA fibres varied with age and sex, increasing in stallions from 34 to 53 per cent and in mares from 27 to 45 per cent, respectively. Correspondingly, the proportion of Type IIB fibres decreased with age and differed between sexes (stallions from 56 to 29 per cent and mares from 65 to 40 per cent) Muscle oxidative capacity increased with age as indicated by significant increases in the activities of citrate synthase (from 32 to 67 mmol/kg/min) and 3-OH-acyl-CoA dehydrogenase (from 20 to 34 mmol/kg/min). The activity of hexokinase increased with age (from 2.4 to 4.8 mmol/kg/min), whereas the activity of lactate dehydrogenase decreased (from 1,754 to 1,444 mmol/kg/min). No differences were seen between stallions and mares in enzyme activities. This study shows that age is one factor influencing enzyme activities, the percentage of Type I fibres and the Type IIA/IIB ratio in M. gluteus medius of Thoroughbreds, and that stallions have a higher Type IIA/IIB ratio compared with mares.
Publication Date: 1991-05-01 PubMed ID: 1884703DOI: 10.1111/j.2042-3306.1991.tb02757.xGoogle Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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The research involves a study on muscle characteristics varying with age and sex in Thoroughbred horses. The samples were taken from the middle gluteal muscle in 163 healthy Thoroughbreds aged one to six years. The muscle characteristics and enzyme activities were studied and related to age and sex.
Methodology
- The researchers took biopsies from the middle gluteal muscle of 163 Thoroughbreds aged one to six years.
- The horses were categorised by sex and grouped into four different age categories (one, two, three, and four to six years).
- Muscle biopsies were analysed for fibre type (I, IIA, and IIB).
- The enzyme activities of citrate synthase, 3-OH-acyl-CoA dehydrogenase, lactate dehydrogenase, and hexokinase were measured.
Findings
- The study found that the percentage of Type I fibres in all horses increased with age, irrespective of sex – ranging from 9 to 16 per cent.
- The percentage of Type IIA fibres varied with age and sex, increasing in stallions from 34 to 53 per cent and in mares from 27 to 45 per cent.
- The proportion of Type IIB fibres decreased with age and differed between sexes – stallions from 56 to 29 per cent and mares from 65 to 40 per cent.
- Muscle oxidative capacity increased with age as indicated by significant increases in the activities of citrate synthase (from 32 to 67 mmol/kg/min) and 3-OH-acyl-CoA dehydrogenase (from 20 to 34 mmol/kg/min).
- The activity of hexokinase increased with age (from 2.4 to 4.8 mmol/kg/min), while the activity of lactate dehydrogenase decreased (from 1,754 to 1,444 mmol/kg/min).
- No differences were observed in enzyme activities between stallions and mares.
Conclusion
- The study showed that age is one factor influencing enzyme activities, Type I fibre percentage and the Type IIA/IIB ratio in M. gluteus medius of Thoroughbreds.
- It also revealed that stallions have a higher Type IIA/IIB ratio compared with mares, indicating a sex-based variation in muscle characteristics.
Cite This Article
APA
Ronéus M, Lindholm A, Asheim A.
(1991).
Muscle characteristics in Thoroughbreds of different ages and sexes.
Equine Vet J, 23(3), 207-210.
https://doi.org/10.1111/j.2042-3306.1991.tb02757.x Publication
Researcher Affiliations
- Department of Medicine and Surgery, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, Uppsala, Sweden.
MeSH Terms
- 3-Hydroxyacyl CoA Dehydrogenases / analysis
- Aging / physiology
- Animals
- Biopsy, Needle / veterinary
- Breeding
- Buttocks
- Citrate (si)-Synthase / analysis
- Female
- Hexokinase / analysis
- Horses / anatomy & histology
- Horses / growth & development
- Horses / metabolism
- L-Lactate Dehydrogenase / analysis
- Male
- Muscle Development
- Muscles / anatomy & histology
- Muscles / enzymology
- Sex Characteristics
Citations
This article has been cited 8 times.- Ebisuda Y, Mukai K, Takahashi Y, Yoshida T, Kawano A, Matsuhashi T, Miyata H, Kuwahara M, Ohmura H. Acute exercise in a hot environment increases heat shock protein 70 and peroxisome proliferator-activated receptor γ coactivator 1α mRNA in Thoroughbred horse skeletal muscle.. Front Vet Sci 2023;10:1230212.
- Wang W, Mukai K, Takahashi K, Ohmura H, Takahashi T, Hatta H, Kitaoka Y. Short-term hypoxic training increases monocarboxylate transporter 4 and phosphofructokinase activity in Thoroughbreds.. Physiol Rep 2020 Jun;8(11):e14473.
- Li C, White SH, Warren LK, Wohlgemuth SE. Effects of aging on mitochondrial function in skeletal muscle of American American Quarter Horses.. J Appl Physiol (1985) 2016 Jul 1;121(1):299-311.
- Stefánsdóttir GJ, Ragnarsson S, Gunnarsson V, Jansson A. Physiological response to a breed evaluation field test in Icelandic horses.. Animal 2014 Mar;8(3):431-9.
- Petersen JL, Mickelson JR, Rendahl AK, Valberg SJ, Andersson LS, Axelsson J, Bailey E, Bannasch D, Binns MM, Borges AS, Brama P, da Câmara Machado A, Capomaccio S, Cappelli K, Cothran EG, Distl O, Fox-Clipsham L, Graves KT, Guérin G, Haase B, Hasegawa T, Hemmann K, Hill EW, Leeb T, Lindgren G, Lohi H, Lopes MS, McGivney BA, Mikko S, Orr N, Penedo MC, Piercy RJ, Raekallio M, Rieder S, Røed KH, Swinburne J, Tozaki T, Vaudin M, Wade CM, McCue ME. Genome-wide analysis reveals selection for important traits in domestic horse breeds.. PLoS Genet 2013;9(1):e1003211.
- Revold T, Larsen S, Ihler CF. Prediction of early race starts in Norwegian-Swedish Coldblooded Trotters.. Acta Vet Scand 2010 Sep 22;52(1):53.
- Behnke BJ, McDonough P, Padilla DJ, Musch TI, Poole DC. Oxygen exchange profile in rat muscles of contrasting fibre types.. J Physiol 2003 Jun 1;549(Pt 2):597-605.
- Pösö AR. Monocarboxylate transporters and lactate metabolism in equine athletes: a review.. Acta Vet Scand 2002;43(2):63-74.
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