Distal Limbs Of Horses Research Articles

Systematic approach to localisation of lameness in the distal limb of horses

Background: Lameness examination is commonly required in equine veterinary practice, whether it's to investigate a lameness already identified by the owner, or as part of the investigation of poor performance.Aim of the article: This article outlines a systematic approach to adopt when presented with a lame horse. Although it focuses on examination of the distal limb, the same principles apply when examining the proximal limb.

Экстерьерные особенности лошадей скифского времени из археологических памятников Северного Кавказа

Using statistical methods, a comparative morphometric analysis of the bones of the distal limbs of horses from archaeological sites of the 7 th—4 th centuries BC was carried out for the first time for the territory of the North Caucasus, in particular the Ciscaucasia, Central and Northwestern Caucasus. In total, the analysis includes 14 sites, materials from 12 of them are published for the first time. The exterior of the horses is described, and some of its changes over 400 years are revealed. It is shown that along with the general uniformity of animals, there are certain differences between the sites left by different archaeological cultures. However, these ethnocultural features can also be largely due to differences in the ecological and geographical conditions for horse breeding. The limited amount of material does not allow us to confidently assert the presence of directed selection of horses and breed formation in this historical period, to determine the origin of horses from different archaeological cultures. However, the general uniformity of animals may indicate, if not the origin, then at least the significant influence of the Scythian horses on the local population. The paper also discusses some methodological aspects of the study of archaeozoological material.

The Effect of Intravenous Regional Perfusion of the Distal Limb With Amikacin Sulfate on Wounds Healing by Second Intention in Horses.

To compare the gross and histological effects of intravenous regional limb perfusion (IVRLP) using amikacin sulfate on second intention healing of distal limb wounds in adult horses with healing in untreated wounds. In vivo experimental study. Adult horses (n = 7). Two full thickness wounds (2.5 × 2.5 cm) were created aseptically on the dorsal aspect of each metacarpus and maintained under sterile bandages. One forelimb was randomly selected from each horse for IVRLP on days 2, 3, and 4 post-wounding. Sequential biopsies were taken from 1 wound on each limb to evaluate the histological effects of IVRLP. Photographs were obtained of nonbiopsied wounds from days 2 to 62 for gross assessment and wound measurement. Wound size and contraction, healing rate during and immediately after IVRLP treatment, total healing rate, and histological scores for edema, hemorrhage, inflammatory infiltrate, and fibrovascular proliferation were compared. No differences were observed between groups for wound size, wound contraction, healing rates during or after IVRLP treatment periods, or total healing rate. Wound size over time was larger in the IVRLP group compared with the control group; however, this difference did not reach statistical significance. Mononuclear cell infiltration was greater in the IVRLP group compared with controls. No differences were observed for other histological variables. All wounds healed without the formation of exuberant granulation tissue. Treatment for 3 consecutive days with IVRLP using amikacin sulfate did not negatively affect surgical wounds healing by second intention in the distal limb of horses.

Moist Exposed Burn Ointment (MEBO) Dressing in Treatment of Equine Limb Distal Wounds

Numerous topical wound medicants are available today. Very few of these products have been tested in horses. Due to the unique nature of wound healing in the distal limbs of horses (carpus, tarsus and distad), many of these medicants seen in different animals but not been reproduced in equine limb wounds. The present investigation aimed to determine if application of Moist exposed Burn ointment (MEBO) dressing would improve measures of wound healing compared with a non‐adherent, semi-occlusive dressing applied to wounds created on the distal aspect of the equine limb. The study was performed on five clinically healthy non castrated horses weighing, 380–500 kg and aged from 14 -–17 years. A 6.25 cm2 wound was created on the dorsomedial aspect of the proximal metacarpus on each forelimb. A MEBO dressing was applied to one limb as a treatment and a non‐adherent, semi-occlusive dressing was applied to the contralateral limb as a control. Bandages were changed every 3 days for 39 days. Granulation tissue was scored and wound area measured every 3 days. The result of this study revealed that MEBO treatment accelerated wound healing in each horse and complete closure was achieved on average 9.4 ± 1.7 days sooner than in control wounds (p < 0.01). In addition, MEBO wound dressing did not increase granulation relative to control at any time point. It was concluded that MEBO wound dressing improved some measures of wound healing compared with the control dressing most significantly during the first 30 days. This suggests that MEBO wound dressing may be useful in the early management of wounds on the equine lower limb.

Regenerative healing, scar-free healing and scar formation across the species: current concepts and future perspectives.

All species have evolved mechanisms of repair to restore tissue function following injury. Skin scarring is an inevitable and permanent endpoint for many postnatal organisms except for non-amniote vertebrates such as amphibians, which are capable of tissue regeneration. Furthermore, mammalian foetuses through mid-gestation are capable of rapid wound repair in the absence of scar formation. Notably, excessive cutaneous scar formation, such as hypertrophic and keloid scars, is a species limited clinical entity as it occurs only in humans, although wounds on the distal limbs of horses are also prone to heal with fibroproliferative pathology known as equine exuberant granulation tissue. Currently, there are no reliable treatment options to eradicate or prevent scarring in humans and vertebrates. The limited number of vertebrate models for either hypertrophic or keloid scarring has been an impediment to mechanistic studies of these diseases and the development of therapies. In this viewpoint essay, we highlight the current concepts of regenerative, scar-free and scar-forming healing compared across a number of species and speculate on areas for future research. Furthermore, in-depth investigative research into the mechanisms of scarless repair may allow for the development of improved animal models and novel targets for scar prevention. As the ability to heal in both a scarless manner and propensity for healing with excessive scar formation is highly species dependent, understanding similarities and differences in healing across species as it relates to the regenerative process may hold the key to improve scarring and guide translational wound-healing studies.

Comparison of two software packages for determining radiographic bone aluminium equivalent values

Radiographic photodensitometry has been used to track changes in bone mineral content in the distal limb of horses through traditional film radiographs. With increasing popularity of digital radiographs, the technique has been adapted for digital technology. The objective of this study was to validate and describe the analysis of digital radiographs and to compare traditional densitometric analysis to digital analysis. Twelve traditional and 12 digital radiographs were taken of the left third metacarpal (MCIII) of 12 horses with an aluminium stepwedge penetrometer attached to the radiographic cassette. Both medial-lateral and dorsal-palmar views were represented. The traditional and digital radiographs were each analysed using two different methods to compare results. Analysis involved determining optical density at each step of the aluminium stepwedge, plotting optical density verses mm Al, and then determining the equation of the subsequent line. The optical density of each cortice was inserted into the equation and radiographic bone aluminium equivalents (RBAE) in mm Al for each cortice was determined. Total RBAE was also examined 1 cm distal to the nutrient foramen of the MCIII. Data were analysed using Proc CORR (SAS v. 9.1) and are reported as mean ± standard deviation. Total RBAE on the dorsal-palmar view from traditional radiographs averaged 286±154 mm Al for digital analysis and 292±173 mm Al for densitometric analysis (R2=0.98). Total RBAE on medial-lateral view from the digital radiographs averaged 539±137 mm Al for digital analysis and 530±165 mm Al for densitometric analysis (R2=0.95). The results demonstrate high correlations between analyses, thereby validating that digital analysis yields similar results as densitometric analysis. Digital radiographs, with increased clarity as compared to traditional films, should allow greater ability to detect treatment differences in research trials, and monitor changes associated with training or nutrition.

In this issue – June 2009

Bandaging and second intention healing in distal limbs of horses ▪ Auricular chondrosis in a horse ▪ National survey of antimicrobials in the Australian pig industry ▪ Analgesia for knife and ring castration in lambs ▪ Incidence of lymphoma in a colony of baboons ▪ Viruses in black tiger prawns from Weipa ▪ Sacral osteochondrosis in German Shepherd Dogs ▪ Congenital pyloric obstruction from a gastric hyperplastic polyp

Laminin receptor 1 is differentially expressed in thoracic and limb wounds in the horse

Healing of wounds located on the distal limbs of horses is often complicated by retarded epithelialization and the development of exuberant granulation tissue (proud flesh). Treatments that definitively resolve this pathological process are still unavailable. Molecular studies of the repair mechanism might contribute to the development of new therapeutic strategies. The study presented herein aimed to clone the full length cDNA and to study the spatio-temporal expression profile of mRNA and protein for LAMR1, previously attributed a role in wound epithelialization, during the repair of body and limb wounds in the horse. Cloning was achieved by screening a cDNA library previously derived from 7-day wound biopsies. Expression was studied in unwounded skin and in samples from 1-, 2-, 3-, 4- and 6-week-old wounds of the body and limb. Temporal gene expression was determined by real time polymerase chain reaction (RT-PCR) while protein expression was mapped immunohistochemically. Full-length cDNA for equine LAMR1 was shown to be highly similar to that of other species. The mRNA expression of LAMR1 was significantly up-regulated only in thoracic wounds, 4 and 6 weeks following wounding (upon epithelialization). Cutaneous wounding induced protein expression at both locations. Our data suggest that up-regulation of LAMR1 protein might favour epithelialization during wound healing. However, its interaction with ligands other than laminin complicates data interpretation. Future studies should quantitatively verify the temporal expression of this protein in order to provide the basis for targeted therapies that might enhance epithelialization.

Cutaneous habronemiasis in a 9‐year‐old Arab gelding in the United Kingdom

SummaryCutaneous habronemiasis causes ulcerative granulating lesions in the skin of equids. Dramatic exuberant tissue may be seen, which becomes traumatised by the horse. To the authors' knowledge, cutaneous habronemiasis has not previously been documented on the distal limb of horses in the UK. Cutaneous habronemiasis should be considered as a potential differential diagnosis for ulcerative granulating skin lesions on the distal limb of the horse.

Factors affecting outcome of extensor tendon lacerations in the distal limb of horses

Distal limb lacerations are common injuries in horses, with a better prognosis reported for extensor tendons lacerations compared to flexor tendons lacerations. The objective of the present study was to determine the influence of type and location of injury, modalities of treatment and post surgical complications on the outcome of extensor tendon lacerations. The medical records of 156 horses surgically treated for extensor tendon lacerations over a 10-year period were analysed retrospectively. Information was obtained for 124 horses with a minimum of 18 months follow-up. Statistical analysis was performed on 129 horses (five horses were euthanatized during hospitalization) in order to determine factors affecting outcome. Seventy-four percent of the horses returned to soundness, 17% had moderate gait impairment and 9% remained lame. Approximately 60% of the sports horses returned to an equal or higher level of performance, and 17.5% returned to a lower level. In the multivariate statistical analysis, the only significant factor that favourably influenced outcome was complete suture of the wound. A significant association could not be detected between outcome and absence of a functional extensor tendon, The most important post-surgical complication was extensive scarring of the wound. The present results report outcome of extensor tendon lacerations in a large number of horses and outline the importance of primary wound healing in order to avoid major scarring with potential functional consequences.

The suitability of Aloe vera products for the treatment of distal limb dermatophilosis in horses

Using acute naturally occurring dermatophilosis infections on the distal limbs of horses, Aloe vera, an effective base for aromatherapy mixtures, was compared to an untreated control and a standard chemotherapeutic treatment over a period of five days along with a mixture of the two treatments. A. vera demonstrated very highly significant remission in infected lesion size compared to untreated controls and significantly larger regression when compared to the chemotherapeutic agent. No significant benefits were observed in combining the two treatments. This contrasts with the in vitro testing of chemotherapeutic agents and A. vera against the causal organism of dermatophilosis which showed highly significant inhibition of Dermatophilus congolensis by some of the conventional treatments compared to A. vera . Re-application of A. vera in vitro brought no significant benefit compared to a single application and several A. vera products were similar in bacterial inhibition. It was concluded that A. vera was a valid treatment for distal limb dermatophilosis in horses in its own right, due to its combination of anti-bacterial activity and superior wound healing ability and that a single application of a common A. vera product was a suitable cost-effective treatment.

Update on topical wound medications

Numerous topical wound medicants are available today. Very few of these products have been tested in the horse. Due to the unique nature of wound healing in the distal limbs of horses (carpus, tarsus and distad), many beneficial effects of these medicants seen in other species and in vitro have not been reproduced in equine limb wounds. There is an abundance of literature regarding topical wound medicants; however, the findings of these studies are quite variable, in general. Many wound care articles have questioned the routine use of topical medications, preferring the concept of moist wound healing in which the body produces all the substrates necessary for adequate wound healing. This article outlines many of the common products that are available to equine practitioners and provides current information regarding their use in wound healing. Unfortunately no product or substrate has been shown to be superior for equine wound management. That being said, the information provided in this article will attempt to provide the practitioner with information necessary to make educated decisions regarding the selection of topical medicants for wound care.