Records |
Author |
Belonje, P.C.; van Niekerk, C.H. |
Title |
A review of the influence of nutrition upon the oestrous cycle and early pregnancy in the mare |
Type |
Journal Article |
Year |
1975 |
Publication |
Journal of Reproduction and Fertility. Supplement |
Abbreviated Journal |
J Reprod Fertil Suppl |
Volume |
|
Issue |
23 |
Pages |
167-169 |
Keywords |
Animals; Body Weight; *Diet; *Estrus; Female; Fertility; Fetal Resorption/prevention & control; Horses/*physiology; Pregnancy |
Abstract |
Attention is drawn to the beneficial effect of improved nutrition during winter and early spring on the ovarian activity of mares. Furthermore, the necessity of an adequate plane of nutrition during early pregnancy to prevent embryonic resorption is stressed. |
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English |
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Edition |
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ISSN |
0449-3087 |
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Conference |
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Notes |
PMID:1060772 |
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no |
Call Number |
Equine Behaviour @ team @ |
Serial |
2225 |
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Author |
Rhodin, M.; Johnston, C.; Holm, K.R.; Wennerstrand, J.; Drevemo, S. |
Title |
The influence of head and neck position on kinematics of the back in riding horses at the walk and trot |
Type |
Journal Article |
Year |
2005 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
Volume |
37 |
Issue |
1 |
Pages |
7-11 |
Keywords |
Acceleration; Animals; Back/*physiology; Biomechanics; Exercise Test/veterinary; Female; Gait/*physiology; Head/*physiology; Horses/*physiology; Male; Movement/physiology; Neck/*physiology; Walking/physiology |
Abstract |
REASONS FOR PERFORMING STUDY: A common opinion among riders and in the literature is that the positioning of the head and neck influences the back of the horse, but this has not yet been measured objectively. OBJECTIVES: To evaluate the effect of head and neck position on the kinematics of the back in riding horses. METHODS: Eight Warmblood riding horses in regular work were studied on a treadmill at walk and trot with the head and neck in 3 different predetermined positions achieved by side reins attached to the bit and to an anticast roller. The 3-dimensional movement of the thoracolumbar spine was measured from the position of skin-fixed markers recorded by infrared videocameras. RESULTS: Head and neck position influenced the movements of the back, especially at the walk. When the head was fixed in a high position at the walk, the flexion-extension movement and lateral bending of the lumbar back, as well as the axial rotation, were significantly reduced when compared to movements with the head free or in a low position. At walk, head and neck position also significantly influenced stride length, which was shortest with the head in a high position. At trot, the stride length was independent of head position. CONCLUSIONS: Restricting and restraining the position and movement of the head and neck alters the movement of the back and stride characteristics. With the head and neck in a high position stride length and flexion and extension of the caudal back were significantly reduced. POTENTIAL RELEVANCE: Use of side reins in training and rehabilitation programmes should be used with an understanding of the possible effects on the horse's back. |
Address |
Department of Anatomy, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden |
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English |
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ISSN |
0425-1644 |
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Notes |
PMID:15651727 |
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no |
Call Number |
Equine Behaviour @ team @ |
Serial |
3657 |
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Author |
Gomez Alvarez, C.B.; Rhodin, M.; Bobber, M.F.; Meyer, H.; Weishaupt, M.A.; Johnston, C.; Van Weeren, P.R. |
Title |
The effect of head and neck position on the thoracolumbar kinematics in the unridden horse |
Type |
Journal Article |
Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
Volume |
|
Issue |
36 |
Pages |
445-451 |
Keywords |
Animals; Biomechanics; Head/*physiology; Horses/*physiology; Lumbar Vertebrae/physiology; Male; Neck/*physiology; Physical Conditioning, Animal/physiology; Posture/*physiology; Sports; Thoracic Vertebrae/physiology; Weight-Bearing |
Abstract |
REASONS FOR PERFORMING STUDY: In many equestrian activities a specific position of head and/or neck is required that is dissimilar to the natural position. There is controversy about the effects of these positions on locomotion pattern, but few quantitative data are available. OBJECTIVES: To quantify the effects of 5 different head and neck positions on thoracolumbar kinematics of the horse. METHODS: Kinematics of 7 high level dressage horses were measured walking and trotting on an instrumented treadmill with the head and neck in the following positions: HNP2 = neck raised, bridge of the nose in front of the vertical; HNP3 = as HNP2 with bridge of the nose behind the vertical; HNP4 = head and neck lowered, nose behind the vertical; HNP5 = head and neck in extreme high position; HNP6 = head and neck forward and downward. HNP1 was a speed-matched control (head and neck unrestrained). RESULTS: The head and neck positions affected only the flexion-extension motion. The positions in which the neck was extended (HNP2, 3, 5) increased extension in the anterior thoracic region, but increased flexion in the posterior thoracic and lumbar region. For HNP4 the pattern was the opposite. Positions 2, 3 and 5 reduced the flexion-extension range of motion (ROM) while HNP4 increased it. HNP5 was the only position that negatively affected intravertebral pattern symmetry and reduced hindlimb protraction. The stride length was significantly reduced at walk in positions 2, 3, 4 and 5. CONCLUSIONS: There is a significant influence of head/neck position on back kinematics. Elevated head and neck induce extension in the thoracic region and flexion in the lumbar region; besides reducing the sagittal range of motion. Lowered head and neck produces the opposite. A very high position of the head and neck seems to disturb normal kinematics. POTENTIAL RELEVANCE: This study provides quantitative data on the effect of head/neck positions on thoracolumbar motion and may help in discussions on the ethical acceptability of some training methods. |
Address |
Department of Equine Sciences, Utrecht University, Yalelaan 12, 3584 CM Utrecht, The Netherlands |
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English |
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Notes |
PMID:17402464 |
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no |
Call Number |
Equine Behaviour @ team @ |
Serial |
3702 |
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Author |
Weishaupt, M.A.; Wiestner, T.; von Peinen, K.; Waldern, N.; Roepstorff, L.; van Weeren, R.; Meyer, H.; Johnston, C. |
Title |
Effect of head and neck position on vertical ground reaction forces and interlimb coordination in the dressage horse ridden at walk and trot on a treadmill |
Type |
Journal Article |
Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
Volume |
|
Issue |
36 |
Pages |
387-392 |
Keywords |
Animals; Biomechanics; Exercise Test/instrumentation/methods/*veterinary; Forelimb/physiology; Gait; Head/physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Male; Neck/physiology; Physical Conditioning, Animal/methods/*physiology; Posture; Statistics, Nonparametric; Walking/*physiology |
Abstract |
REASONS FOR PERFORMING STUDY: Little is known in quantitative terms about the influence of different head-neck positions (HNPs) on the loading pattern of the locomotor apparatus. Therefore it is difficult to predict whether a specific riding technique is beneficial for the horse or if it may increase the risk for injury. OBJECTIVE: To improve the understanding of forelimb-hindlimb balance and its underlying temporal changes in relation to different head and neck positions. METHODS: Vertical ground reaction force and time parameters of each limb were measured in 7 high level dressage horses while being ridden at walk and trot on an instrumented treadmill in 6 predetermined HNPs: HNP1 – free, unrestrained with loose reins; HNP2 – neck raised, bridge of the nose in front of the vertical; HNP3 – neck raised, bridge of the nose behind the vertical; HNP4 – neck lowered and flexed, bridge of the nose considerably behind the vertical; HNP5 – neck extremely elevated and bridge of the nose considerably in front of the vertical; HNP6 – neck and head extended forward and downward. Positions were judged by a qualified dressage judge. HNPs were assessed by comparing the data to a velocity-matched reference HNP (HNP2). Differences were tested using paired t test or Wilcoxon signed rank test (P<0.05). RESULTS: At the walk, stride duration and overreach distance increased in HNP1, but decreased in HNP3 and HNP5. Stride impulse was shifted to the forehand in HNP1 and HNP6, but shifted to the hindquarters in HNP5. At the trot, stride duration increased in HNP4 and HNP5. Overreach distance was shorter in HNP4. Stride impulse shifted to the hindquarters in HNP5. In HNP1 peak forces decreased in the forelimbs; in HNP5 peak forces increased in fore- and hindlimbs. CONCLUSIONS: HNP5 had the biggest impact on limb timing and load distribution and behaved inversely to HNP1 and HNP6. Shortening of forelimb stance duration in HNP5 increased peak forces although the percentage of stride impulse carried by the forelimbs decreased. POTENTIAL RELEVANCE: An extremely high HNP affects functionality much more than an extremely low neck. |
Address |
Equine Hospital, University of Zurich, CH-8057 Zurich, Switzerland |
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English |
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Notes |
PMID:17402453 |
Approved |
no |
Call Number |
Equine Behaviour @ team @ |
Serial |
3704 |
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Author |
Elsaesser, F.; Klobasa, F.; Ellendorff, F. |
Title |
ACTH stimulation test for the determination of salivary cortisol and of cortisol responses as markers of the training status/fitness of warm-blooded sports horses] |
Type |
Journal Article |
Year |
2001 |
Publication |
DTW. Deutsche Tierarztliche Wochenschrift |
Abbreviated Journal |
Dtsch Tierarztl Wochenschr |
Volume |
108 |
Issue |
1 |
Pages |
31-36 |
Keywords |
Adrenocorticotropic Hormone/*diagnostic use; Animals; Health; Horses/*physiology; Hydrocortisone/*analysis/*secretion; Male; Orchiectomy; *Physical Conditioning, Animal; Running; Saliva/*chemistry; Walking |
Abstract |
Previous work (Marc et al., 2000) suggested that plasma cortisol responses to treadmill exercise or ACTH injection are a reliable marker for performance evaluation in warmblood horses. For practical purposes blood sample collections and treadmill exercise tests are somewhat troublesome and time consuming. The goal of this study was thus to evaluate the use of saliva for cortisol determination (by direct EIA) as a marker for performance and to investigate the reliability and repeatability of plasma cortisol responses to a single i.v. injection of ACTH (50 micrograms or 250 micrograms). Furthermore, the effect of training horses for 8 weeks 3 times per week covering the same distance (increasing from 3.5 km during the first week to 8 km during the last week) either by trotting (approximately 240 m/min) or by cantering (375 m/min) was investigated. For this purpose initially ten four-year-old Hannovarian geldings, all reared in the same State stud, were used. Mean overall correlation between salivary cortisol and plasma cortisol concentrations was 0.64 when samples of various points of time were used. However, in spite of attempts to standardize saliva sample collection, correlation between salivary cortisol levels and plasma cortisol levels at distinct points of time in different tests were low and significant (r = 0.85, p < 0.02) only in one test. Thus, salivary cortisol measurements for diagnostic purposes are not reliable or useful. The repeatability of plasma cortisol responses to ACTH for untrained and trained horses were r = 0.86 and r = 0.8 respectively (p < or = 0.01 and p < or = 0.05 respectively). Training horses either by trotting or cantering did not affect the cortisol response either to treadmill exercise or to stimulation by ACTH. It is concluded that the relationship between salivary cortisol levels and plasma cortisol levels is not close enough to allow the use of salivary cortisol determination as marker of the training status/fitness of horses. The repeatability of the cortisol response to ACTH is similar to the cortisol response to treadmill exercise. Based on plasma cortisol responses to ACTH or treadmill exercise training horses by cantering at low speed is not superior to training by trotting for the fitness of horses. |
Address |
Institut fur Tierzucht und Tierverhalten Mariensee (FAL), Holtystrasse 10, 31535 Neustadt. elsaesser@tzv.fal.de |
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Language |
German |
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Original Title |
ACTH Stimulationstest und Bestimmung von Cortisol im Blut und Speichel zur Bewertung des Trainingszustands/der Kondition beim Warmblutpferd |
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ISSN |
0341-6593 |
ISBN |
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Conference |
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Notes |
PMID:11232423 |
Approved |
no |
Call Number |
Equine Behaviour @ team @ |
Serial |
4053 |
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Author |
Berger, J. |
Title |
Induced abortion and social factors in wild horses |
Type |
Journal Article |
Year |
1983 |
Publication |
Nature |
Abbreviated Journal |
Nature |
Volume |
303 |
Issue |
5912 |
Pages |
59-61 |
Keywords |
Abortion, Induced/*veterinary; Abortion, Veterinary/*etiology; Aggression/physiology; Animals; Evolution; Female; Horses/*physiology; Humans; Pregnancy; Sexual Behavior, Animal/*physiology |
Abstract |
Much evidence now suggests that the postnatal killing of young in primates and carnivores, and induced abortions in some rodents, are evolved traits exerting strong selective pressures on adult male and female behaviour. Among ungulates it is perplexing that either no species have developed convergent tactics or that these behaviours are not reported, especially as ungulates have social systems similar to those of members of the above groups. Only in captive horses (Equus caballus) has infant killing been reported. It has been estimated that 40,000 wild horses live in remote areas of the Great Basin Desert of North America (US Department of Interior (Bureau of Land Management), unpublished report), where they occur in harems (females and young) defended by males. Here I present evidence that, rather than killing infants directly, invading males induce abortions in females unprotected by their resident stallions and these females are then inseminated by the new males. |
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English |
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ISSN |
0028-0836 |
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Notes |
PMID:6682487 |
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no |
Call Number |
Equine Behaviour @ team @ |
Serial |
4365 |
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Author |
Ordakowski-Burk, A.L.; Quinn, R.W.; Shellem, T.A.; Vough, L.R. |
Title |
Voluntary intake and digestibility of reed canarygrass and timothy hay fed to horses |
Type |
Journal Article |
Year |
2006 |
Publication |
Journal of Animal Science |
Abbreviated Journal |
J. Anim Sci. |
Volume |
84 |
Issue |
11 |
Pages |
3104-3109 |
Keywords |
Animal Feed/*analysis; Animal Nutrition Physiology; Animals; Diet/*veterinary; Digestion/*physiology; Feeding Behavior/*physiology; Horses/*physiology; Male; Poaceae/*metabolism |
Abstract |
Thousands of hectares of timothy (Phleum pretense L.) grown in the Mid-Atlantic region are infected by cereal rust mite (Abacarus hysterix) that causes discoloration and curling of leaves, decreased nutritional quality, and substantial decreases in yield. A decline in production of timothy hay can lower income for hay producers and cause horse owners to search for alternative hays. Low alkaloid reed canarygrass (Phalaris arundinacea L.) hay has potential as an alternative to timothy hay because it grows well in the Mid-Atlantic region, is believed to have a similar nutrient quality to timothy, and is not as susceptible to cereal rust mite. Eleven mature, stalled Thoroughbred geldings (549 +/- 12.1 kg) that were exercised daily were used to compare voluntary DMI and apparent nutrient DM digestibility of timothy and low-alkaloid Chiefton variety reed canarygrass hay. Horses were paired by age and BW and randomly assigned to timothy or reed canarygrass hay during a 14-d period to measure voluntary DMI followed by a 4-d period to measure apparent DM digestibility. Both hays met the minimum requirements for DE, CP, Ca, P, K, Fe, and Mn, but they did not meet the minimum requirements for Cu, Zn, and Na for horses at maintenance and averaging 550 kg of BW. Timothy hay seemed to have a lower CP concentration (14.4%) compared with reed canarygrass hay (17.1%) and a more desirable Ca:P ratio at 1.6:1 compared with 0.8:1 for reed canarygrass hay. Horses fed timothy consumed more hay (P <0.001) during the voluntary DMI period compared with horses fed reed canarygrass. Greater voluntary DMI of timothy occurred on d 1, 3, and 5 (P <0.05), but DMI was similar for other days. Apparent DM digestibility was greater in horses fed timothy hay by 9.6% compared with horses fed reed canarygrass hay (P <0.05). Horses fed timothy had greater DM digestibility of ADF (P = 0.001), NDF (P = 0.001), sugar (P = 0.05), and Ca (P = 0.001) but lower apparent DM digestibility of CP (P = 0.012) and crude fat (P = 0.004). Timothy hay was superior in voluntary DMI and apparent DM digestibility compared with low-alkaloid reed canarygrass hay fed to horses. |
Address |
Department of Animal and Avian Sciences, University of Maryland, College Park 20742, USA. amyburk@umd.edu |
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1525-3163 |
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Notes |
PMID:17032805 |
Approved |
no |
Call Number |
Equine Behaviour @ team @ |
Serial |
4236 |
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Author |
Dallmeyer, M.D.; Turner, R.M.; McDonnell, S.M.; Sertich, P.L.; Dolente, B.A.; Parente, E.J.; Diaz, O.M.S. |
Title |
Theriogenology question of the month. Behavior problems in a stallion caused by a nephrolith |
Type |
Journal Article |
Year |
2006 |
Publication |
Journal of the American Veterinary Medical Association |
Abbreviated Journal |
J Am Vet Med Assoc |
Volume |
229 |
Issue |
4 |
Pages |
511-513 |
Keywords |
Animals; Behavior, Animal; Horse Diseases/physiopathology/surgery/*ultrasonography; Horses/*physiology; Kidney Calculi/physiopathology/surgery/ultrasonography/*veterinary; Male; Sperm Count/*veterinary; *Sperm Motility; Treatment Outcome |
Abstract |
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Address |
Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA |
Corporate Author |
American College of Theriogenologists |
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English |
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0003-1488 |
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Notes |
PMID:16910847 |
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no |
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Serial |
1865 |
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Author |
Kurvers, C.M.H.C.; van Weeren, P.R.; Rogers, C.W.; van Dierendonck, M.C. |
Title |
Quantification of spontaneous locomotion activity in foals kept in pastures under various management conditions |
Type |
Journal Article |
Year |
2006 |
Publication |
American journal of veterinary research |
Abbreviated Journal |
Am J Vet Res |
Volume |
67 |
Issue |
7 |
Pages |
1212-1217 |
Keywords |
Aging; Animal Husbandry; Animals; Female; Horses/*physiology; Male; Motor Activity/*physiology; Sex Characteristics |
Abstract |
OBJECTIVE: To describe spontaneous locomotion activity of foals kept under various management conditions and assess the suitability of global positioning system (GPS) technology for recording foal activity. Animals-59 foals. PROCEDURES: During the foals' first 4 months of life, 921 observation periods (15 minutes each) were collected and analyzed for locomotion activities. The GPS system was evaluated by simultaneously carrying out field observations with a handheld computer. RESULTS: Foals spent 0.5% of total observed time cantering, 0.2% trotting, 10.7% walking, 32.0% grazing, 34.8% standing, and 21.6% lying down. Total observed daytime workload (velocity x distance) in the first month was approximately twice that in the following months. Locomotion activity decreased with increasing age. Colts had more activity than fillies in certain periods, and foals that were stabled for some portion of the day had compensatory locomotion activity, which was probably insufficient to reach the level of foals kept continually outside. The GPS recordings and handheld-computer observations were strongly correlated for canter, trot, and walk and moderately correlated for standing and lying. Correlation for grazing was low. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that domestically managed foals, when kept 24 h/d at pasture, will exercise at a level comparable with feral foals. High workload during the first month of life might be important for conditioning the musculoskeletal system. The GPS technique accurately quantified canter, trot, and walk activities; less accurately indexed resting; and was unsuitable for grazing because of the wide array of velocities used while foraging. |
Address |
Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, The Netherlands |
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English |
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ISSN |
0002-9645 |
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Notes |
PMID:16817745 |
Approved |
no |
Call Number |
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Serial |
1786 |
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Author |
Skedros, J.G.; Dayton, M.R.; Sybrowsky, C.L.; Bloebaum, R.D.; Bachus, K.N. |
Title |
The influence of collagen fiber orientation and other histocompositional characteristics on the mechanical properties of equine cortical bone |
Type |
Journal Article |
Year |
2006 |
Publication |
The Journal of Experimental Biology |
Abbreviated Journal |
J Exp Biol |
Volume |
209 |
Issue |
Pt 15 |
Pages |
3025-3042 |
Keywords |
Animals; Biomechanics; Bone and Bones/*physiology; Collagen/*physiology; Forelimb; Horses/*physiology |
Abstract |
This study examined relative influences of predominant collagen fiber orientation (CFO), mineralization (% ash), and other microstructural characteristics on the mechanical properties of equine cortical bone. Using strain-mode-specific (S-M-S) testing (compression testing of bone habitually loaded in compression; tension testing of bone habitually loaded in tension), the relative mechanical importance of CFO and other material characteristics were examined in equine third metacarpals (MC3s). This model was chosen since it had a consistent non-uniform strain distribution estimated by finite element analysis (FEA) near mid-diaphysis of a thoroughbred horse, net tension in the dorsal/lateral cortices and net compression in the palmar/medial cortices. Bone specimens from regions habitually loaded in tension or compression were: (1) tested to failure in both axial compression and tension in order to contrast S-M-S vs non-S-M-S behavior, and (2) analyzed for CFO, % ash, porosity, fractional area of secondary osteonal bone, osteon cross-sectional area, and population densities of secondary osteons and osteocyte lacunae. Multivariate multiple regression analyses revealed that in S-M-S compression testing, CFO most strongly influenced total energy (pre-yield elastic energy plus post-yield plastic energy); in S-M-S tension testing CFO most strongly influenced post-yield energy and total energy. CFO was less important in explaining S-M-S elastic modulus, and yield and ultimate stress. Therefore, in S-M-S loading CFO appears to be important in influencing energy absorption, whereas the other characteristics have a more dominant influence in elastic modulus, pre-yield behavior and strength. These data generally support the hypothesis that differentially affecting S-M-S energy absorption may be an important consequence of regional histocompositional heterogeneity in the equine MC3. Data inconsistent with the hypothesis, including the lack of highly longitudinal collagen in the dorsal-lateral ;tension' region, paradoxical histologic organization in some locations, and lack of significantly improved S-M-S properties in some locations, might reflect the absence of a similar habitual strain distribution in all bones. An alternative strain distribution based on in vivo strain measurements, without FEA, on non-Thoroughbreds showing net compression along the dorsal-palmar axis might be more characteristic of the habitual loading of some of the bones that we examined. In turn, some inconsistencies might also reflect the complex torsion/bending loading regime that the MC3 sustains when the animal undergoes a variety of gaits and activities, which may be representative of only a portion of our animals, again reflecting the possibility that not all of the bones examined had similar habitual loading histories. |
Address |
Utah Bone and Joint Center, 5323 S. Woodrow Street #202, Salt Lake City, UT 84107, USA. jskedros@utahboneandjoint.com |
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English |
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0022-0949 |
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Notes |
PMID:16857886 |
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no |
Call Number |
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Serial |
1868 |
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