Repair of Fractures of the Distal Aspect of the Radius in Two Horses

Fractures of the distal radius in two horses were repaired by open reduction and interfragmentary compression using screws placed in a lag fashion. One horse had a complete oblique fracture of the medial aspect of the epiphysis of the distal radius and was sound for riding 32 months after surgery. The other horse had an open spiral comminuted fracture with medial displacement of the distal radial fragment. Laminitis developed in the contralateral limb and this horse was euthanatized 5 weeks after surgery. © Copyright 1994 by The American College of Veterinary Surgeons     

Puncture Wounds of the Navicular Bursa in 38 Horses A Retrospective Study

The medical records of 38 horses with puncture wounds of the navicular bursa were reviewed. Only 12 horses had a satisfactory outcome (breeding or riding). Of the remaining 26 horses, 19 were euthanized, five were sold due to persistent severe lameness, one died, and one was lost to long-term follow-up. Different combinations of conservative management prior to surgical debridement and drainage of the navicular bursa were unsuccessful in resolving the condition. Horses that were treated surgically within 1 week of the injury and had a hind leg affected had the best chance of a satisfactory outcome. Additional wound debridement was necessary in 15 horses after initial surgical treatment. The most common complications encountered were navicular bone osteomyelitis and sepsis of the deep digital flexor tendon. Thirteen of 14 horses that had rupture of the deep digital flexor tendon and subluxation of the distal interphalangeal joint had an unsatisfactory outcome. One mare subsequently developed ankylosis of the distal interphalangeal joint and was a useful brood mare. Two horses that had biaxial palmar digital neurectomy because of persistent lameness were later euthanized because of navicular bone fracture and rupture of the deep digital flexor tendon. Results from limited numbers of bacterial cultures and antibiotic sensitivities suggest that penicillin and an aminoglycoside antibiotic should be used as initial antibiotic therapy. Immediate surgical debridement and appropriate antibiotic treatment are recommended as the minimum therapy for penetrating wounds of the navicular bursa in horses.     

Morphometrical Study of Bony Elements of the Forelimb Fetlock Joints in Horses

There are many reports describing fractures in the bony elements of the equine fetlock joint and a few of these discuss possible relationships of these fractures to the mechanical loading of these bones. The likelihood of fracture must be related to the size and shape of bones involved, but information concerning the normal range in size and shape of these bones in horses is lacking. This study aimed to identify morphometrical variations of these bones within different groups of horses. Right and left metacarpal, proximal phalangeal and proximal sesamoid bones were collected from 10 Thoroughbreds (TB), five Standardbreds (SB) and eight Ponies (P) euthanized for non‐orthopaedic reasons. All bones were boiled, cleaned and dried. Dimensional parameters were measured using a custom‐built apparatus, calliper and plastic tape. The width and depth of the medial condyles of Mc3 were greater than the lateral condyles in all groups. The length to the lateral condyle was greater than the length to the medial condyle of Mc3, and the lengths of the lateral sides of the Mc3 and P1 bones were greater than the lengths of the medial sides in both forelimbs of all groups. The lateral sesamoids were similar to, or larger than, the medial sesamoids in all dimensions. There were some morphometrical variations in the bony elements of the equine fetlock joints in all groups.     

A Preliminary Study Examining the Digital Cushion in Horses

The digital cushion is important for the dissipation of impact as the foot contacts the ground. If there is inefficient energy dissipation, potential exists for changes to occur in the foot. Although ultrasonic imaging of the digital cushion has been reported, it is unknown if these measurements account for compositional changes that have been reported across age, breed, and between fore and hind feet. Therefore, the objective of this preliminary study was to establish baseline values in mature, stock type horses with adequate body condition score (BCS). To meet this objective, 24 mature, stock-type horses of similar age, height, and weight were used to establish baseline values for the digital cushion thickness in the live horse. All horses were sound at the time of data collection and had no known history of long-term lameness conditions. Digital cushion thickness of the left fore and left hind foot was determined using ultrasound through the transcuneal approach. Data were analyzed using the PROC MEANS and PROC GLM procedure of SAS with a least square means statement. Significance was set at P ≤ .05. Mean values (±standard error [SE]) for age, weight, height, and BCS were 10.7 ± 0.86 years, 476.2 ± 7.75 kg, 153.56 ± 0.90 cm, and 5.6 ± 0.12, respectively. Mean values (±SE) for the digital cushion of the left fore and left hind were 0.96 ± 0.03 and 1.02 ± 0.04 cm, respectively. When comparing the left fore and left hind, there was no significant difference observed. Overall, baseline values of digital cushion thickness for fore and hind feet were established, allowing for future studies to assess the different variables known to affect digital cushion composition.     

焦虫净治疗马类家畜焦虫病试验初报

焦虫净是本所研制的一种新型速效缓释肌肉注射抗（杀）焦虫药物,主要成分为环烯醚萜类。用其治疗牛、羊焦虫病取得了满意效果。为了研究其对马类家畜焦虫病的疗效,笔者拟在焦虫病流行区域—甘肃省礼县进行了本试验。１材料与方法１．１试验动物甘肃省礼县崖城、罗坝、永...     

Use of Body-Mounted Inertial Sensors to Objectively Evaluate the Response to Perineural Analgesia of the Distal Limb and Intra-articular Analgesia of the Distal Interphalangeal Joint in Horses With Forelimb Lameness

Diagnostic analgesia of the distal interphalangeal (DIP) joint is theoretically helpful to localize the source of pain in the foot to the joint and/or navicular bursa. However, it has been suggested that potential diffusion of local anesthetic agent to nearby distal limb nerves may anesthetize other areas of the foot. The objective of this study was to compare the results of palmar digital (PD) and abaxial sesamoid (AS) nerve blocks to intra-articular anesthesia of the DIP joint in horses with distal forelimb lameness. Palmar digital nerve block (group 1) or PD and AS nerve blocks (group 2) were used to abolish digital pain in 22 horses. The following day lameness was again evaluated in all horses before and 2, 5, and 10 minutes after DIP joint anesthesia. All lameness evaluations were performed objectively with a body-mounted inertial sensor system (Lameness locator; Equinosis LLC, Columbia, MO). In group 1 horses, overall improvement in group lameness was the same after DIP joint block, but only six showed positive response after DIP joint analgesia, five after 2 minutes, and one after 5 minutes. In group 2 horses, overall improvement in lameness was less after DIP joint block, with seven showing a positive response after DIP joint analgesia, one after 2 minutes, four after 5 minutes, and two after 10 minutes. Intra-articular analgesia of the DIP joint and perineural analgesia of the digit result in overlapping but unequal areas of analgesia. In addition, a time-dependent response was observed after DIP joint block with full effect requiring 5–10 minutes.     

中国矮马运铁蛋白遗传多态性的初步研究

采用聚丙烯酰胺凝胶电泳对中国矮马运铁蛋白多态性进行了测定。在运铁蛋白位点共发现5种表型，即F2F2，DF2，F2H2，F2O和F2R，由Tf^D,Tf^F2,Tf^F2,Tf^H2,Tf^O和Tf^R等5个等位基因控制，其基因频率分别为0.0312,0.7188,0.0625,0.0312和0.1563；基因的杂合度（H），个体鉴别概率（Dp)和亲仔关系排除概率（PE）分别为0.4530,0.6875和0.2586。     

Effects of Steel and Aluminum Shoes on Forelimb Kinematics in Stock-Type Horses as Measured at the Trot

To meet the needs of sport horses, horseshoes of various styles and materials have been implemented to enhance performance. Steel shoes are commonly used for their affordability and longevity; however, the use of aluminum horseshoes is being adopted to satisfy the various requirements of certain equestrian activities. Owing to the importance of the allure of movement in many aspects of competitive riding, the lightweight nature of aluminum horseshoes has been recognized to accentuate foreleg action. By performing a repeated-measures crossover study on nine healthy stock-type horses, the effects of these two horseshoe types on forelimb action were analyzed at the trot using two-dimensional kinematics. Horses were trotted in hand for three repetitions over a distance of 50.1 meters on days 4, 18, 32, and 46 postshoeing for two 6-week shoeing cycles. Video footage was collected and analyzed using gait analysis software (EquineTec) for each repetition. The measured stride length, fetlock extension, elbow and knee range of motion, and minimum and maximum elbow angle remained constant between treatments. However, there was a significant treatment effect on minimum carpal angle and maximum hoof height, with aluminum shoes having a larger minimum carpal angle than those in steel shoes (P < .05) and a lower maximum hoof height (P < .05). An overall 3-degree difference in minimum carpal angle and approximate 2.5-cm difference in maximum hoof height was observed between treatments. This finding is of particular importance to performance horse disciplines for which a lesser degree of knee action is desirable.     

The Association of Propofol Usage With Postoperative Wound Infection Rate in Clean Wounds: A Retrospective Study

OBJECTIVE: To determine if the use of propofol influences the postoperative infection rate of clean surgical wounds in dogs and cats. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: 863 dogs and cats undergoing clean surgical procedures. METHODS: Medical and anesthetic records of surgical cases used as part of a previously described epidemiologic study on postoperative wound infection rates were reviewed. The records of all animals with clean surgical wounds were reviewed to determine if propofol had been used for anesthetic induction or maintenance during the procedure. To determine the effect of propofol use on wound infection rate, data were analyzed using Fisher's exact test, followed by multiple logistic regression to adjust for various factors, including surgery time, time from clipping to surgery, antibiotic usage, coexisting distant infection, endocrine disease, and the use of immunosuppressive drugs in the perioperative period. RESULTS AND CONCLUSIONS: Of 863 dogs and cats with clean surgical wounds, 46 received propofol as part of the anesthetic protocol. A total of 6 of 46 animals (13%) receiving propofol developed postoperative wound infections, compared with 33 of 817 animals (4%) not receiving propofol (P = .014; % difference = 9%; 95% CI = 0.5% to 24%). Adjusting for all other factors evaluated, animals receiving propofol were 3.8 times more likely to develop postoperative wound infections compared to animals not given propofol (95% CI = 1.5-9.9). CLINICAL IMPLICATIONS: Propofol is a lipid-based emulsion capable of supporting microbial growth. Administration of a potentially contaminated solution may contribute to surgical wound infection or other patient morbidity or mortality. Strict aseptic technique in the preparation of the solution and prompt disposal of unused drug are imperative to curtail the potential for extrinsic contamination.     

Stress Protection Afforded by a Cast on Plate Fixation of the Distal Forelimb in the Horse In Vitro

Six forelimb specimens from three adult horses had the fetlock joint fused by application of a dorsal plate and by a screw placed in lag fashion through the metacarpus to each proximal sesamoid bone. Five specimens were instrumented on the central dorsal surface of the plate with a single rosette strain gage, and the plate of the sixth specimen was instrumented with four longitudinally oriented single-axis strain gages. The specimens were loaded axially in compression to 4,000 N in a cast (test 1), in a cast with a heel block (test 2), and uncast (test 3). The principal angle of strain in all specimens, in all tests, closely approximated the vertical axis at loads < 1,000 N. The principal angle in uncast specimens was significantly different at loads > 1,000 N than the cast specimens ( P <.05). At loads > 3,000 N, the principal angle in test 3 closely approximated the horizontal axis, indicating a change from tension to compression on the dorsal surface of the plate, whereas the principal angle of the cast specimens was unchanged. Specimens in a cast (tests 1 and 2) suffered less surface deformation than did uncast specimens (test 3). Therefore, the cast changed the direction and extent of bending at the point of fixation, and thereby decreased the deformation of the plate. This effect would lead to greater fatigue life of the implant in the cast specimens compared with the uncast specimens.     

Acute Phase Response to Surgery of Varying Intensity in Horses: A Preliminary Study

Objective— To evaluate the postoperative inflammatory response of horses to elective surgery of varying intensity.
Study Design— Prospective longitudinal study.
Animals— Horses referred to 2 hospitals for either arthroscopic removal of a unilateral osteochondritic lesion in the tibiotarsal joint (minimal surgical trauma, n=11), correction of recurrent laryngeal neuropathy by laryngoplasty and ventriculectomy (intermediate surgical trauma, n=10) or removal of an ovarian tumor by laparotomy (major surgical trauma, n=5).
Methods— Horses had a thorough clinical examination every day. White blood cell (WBC) counts and concentrations of serum amyloid A (SAA), fibrinogen, and iron were assessed in blood samples obtained before, and 1–3, 5, 7, 9, and 11 days after surgery. Differences in levels of the inflammatory markers between the 3 surgical groups were analyzed using repeated measures ANOVA.
Results— Postoperative concentrations of SAA and fibrinogen were significantly higher in horses that had laparotomy and ovariectomy than in horses that had laryngoplasty and ventriculectomy, or arthroscopy. Iron concentrations decreased to lower levels after intermediate and major surgical trauma than after small surgical trauma. WBC count did not differ between the 3 groups.
Conclusions— Levels of SAA, fibrinogen, and iron reflected the intensity of the surgical trauma, whereas WBC count did not.
Clinical Relevance— Postoperative measurements of SAA, fibrinogen, and iron may be useful for comparing surgical trauma associated with new and established surgical techniques. Moreover, knowledge of the normal postoperative acute phase response is essential, if acute phase reactants are to be used for monitoring occurrence of postoperative infections.     

Delayed Wound Closure A Review and Report of Use of the Technique on Three Equine Limb Wounds

Limb wounds of three horses were managed by delayed wound closure. In each, the wound was such that it was unlikely that healing would occur following primary closure and that second intention healing would have been unsatisfactory. Wounds were cleaned and debrided at the time of admission and maintained under sterile pressure bandages until free of infection and devitalized tissue. Suture closure of the wound at that time resulted in satisfactory healing in each case.     

A Preliminary Study of 13C-Phenylalanine and 13C-Dipeptide Breath Tests in Horses

This study aimed to establish a standard dose and sample collection time for ¹³C phenylalanine and ¹³C-Dipeptide breath test in horses. To evaluate dose-dependent effects, healthy horses received 2.5 mg/kg, 5 mg/kg, and 10 mg/kg ¹³C phenylalanine dissolved in 1 ml/kg distilled water and 1.25 mg/kg, 2.5 mg/kg, and 5 mg/kg ¹³C dipeptide dissolved in 2 ml/ kg distilled water. Tmax was observed during the sample collection time. For ¹³C phenylalanine, the standard deviation of Cmax at 5 mg/kg was lower than that of 10 mg/kg. For ¹³C dipeptide, the standard deviation of Tmax was the lowest at 5 mg/kg. This study revealed that an optimal dose for breath tests with ¹³C phenylalanine and ¹³C dipeptide may be 5 mg/kg in horses.     

岔口驿马细管冻精制作与人工授精推广方案初探

为了进一步保护、发展和利用岔口驿马种质资源,扩大岔口驿马种群数量,有关研究人员制定适合岔口驿马种属区域的细管冻精制作和人工授精技术示范及推广方案,以期为实现岔口驿马产业的高质量发展和岔口驿马品种改良应用提供参考依据。     

Preliminary Study on Age- and Sex-Dependent Alterations in the Composition of Skeletal Muscle Fibers of Brasileiro de Hipismo Horses

The aim of this work was to characterize the distribution of myofibers in the gluteus medius muscle of inactive horses of the Brasileiro de Hipismo (BH) breed at different ages by means of histochemical analyses, according to sex and depth of the biopsy. A total of 78 inactive horses (9 castrated males, 35 stallions, and 34 females) of the BH breed, aged 1 to 4 years, were used. A percutaneous muscle biopsy was obtained with a 6.0-mm Bergström-type needle, which allowed the removal of muscle fragments at depths of 20 and 60 mm. Myofiber types were determined based on myofibrillar adenosine triphosphatase (mATPase) and nicotinamide dinucleotide tetrazolium reductase (NADH-TR) techniques. Morphometry of the fibers was determined based on cross-sectional area (CSA), mean frequency (F), and relative cross-sectional area (RCSA). The current study demonstrated that BH horses 3 and 4 years of age show a greater percentage of, and area occupied by, type IIA fibers and lower percentage of type IIX fibers in the gluteus medius muscle compared with horses 1 and 2 years of age. No difference was found between sexes in the frequency of and area occupied by the different fiber types at any of the depths and ages studied. In this study, females showed a greater CSA for all fibers in comparison with males, at 1 year of age. The results of the current study indicate that the gluteus medius muscle of inactive BH horses shows modifications in its structural and biochemical composition during the growth of the animals, leading to a better oxidative capacity.     

A Field Study on the Effect of Some Anthelmintics on Cyathostomins of Horses in Sweden

The objective of the study was to investigate different aspects on the efficacy of three anthelmintics on cyathostomin nematodes of Swedish horses. A faecal egg count reduction (FECR) test was performed on 26 farms. Horses were treated orally with recommended doses of ivermectin, pyrantel pamoate or fenbendazole. Faecal samples were collected on the day of deworming and 7, 14 and 21 days later. No resistance was shown against ivermectin; the FECR was constantly >99%. The effect of pyrantel was assessed as equivocal in 6 farms 14 days after treatment; the mean FECR was 99%. As many as 72% of the fenbendazole-treated groups met the criteria for resistance; the mean FECR was 86%, ranging from 56% to 100%. A re-investigation of two farms where pyrantel resistance had been suspected clearly revealed unsatisfactory efficacy of pyrantel on one of these farms; the FECR varied from 72% to 89%. Twenty-six of the horses previously dosed with pyrantel or fenbendazole, and which still excreted ≥150 eggs per gram of faeces 14 days after treatment, were dewormed with ivermectin and fenbendazole or pyrantel in order to eliminate the remaining cyathostomins. A total of 13 cyathostomin species were identified from horses that initially received fenbendazole and seven species were identified from pyrantel-treated individuals. The egg reappearance period (ERP) following treatment with ivermectin and pyrantel was investigated on two farms. The shortest ERP after ivermectin treatment was 8 weeks and after pyrantel was 5 weeks. We conclude that no substantial reversion to benzimidazole susceptibility had taken place, although these drugs have scarcely been used (<5%) in horses for the last 10 years. Pyrantel-resistant populations of cyathostomins are present on Swedish horse farms, but the overall efficacy of pyrantel is still acceptable.