ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01596.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01597.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SummaryCase records and radiographs of 71 horses with subchondral lucency, without radiographic evidence of fracture, located on the distal radial carpal bone were examined retrospectively. All horses had lameness and/or joint effusion referable to the carpus. Distal radial carpal bone subchondral lucency was found as a solitary lesion or as a lesion concurrent and symmetric to a contralateral distal radial carpal bone chip fracture. The lesion appeared radiographically as a lucency or shadow on the distal dorsal margin of the radial carpal bone and was most evident on the flexed lateromedial and dorsolateral‐palmaromedial oblique projections. Sixty‐four joints in 55 horses underwent arthroscopic surgery. Surgical findings included osteochondral fragmentation in 44 joints, cartilage fragmentation with subchondral bone softening in 17 joints and cartilage fraying in 3 joints. Corresponding third carpal bone lesions were observed in 18 joints and moderate to severe synovitis was present in 24 joints. Carpal bone subchondral radiolucency without a fracture fragment observed on radiographs indicated cartilage and bone damage. In some cases, small chip fractures (1–2 mm) were present within the cartilage debris examined at surgery, yet were not radiographically visible. Follow‐up information was obtained on 50 of the operated horses and 14 nonoperated horses. Forty (80%) of the surgically treated horses returned to racing, with 34 (68%) of these horses (20 of 26 with subchondral lucency as a solitary lesion) racing at a level of competition equal to or better than the pre‐injury level. Of the 14 horses which were not operated, 6 (42%) returned to racing of which only 2 (14%) raced at the same pre‐injury level of competition. Radiographic evidence of radial or intermediate carpal bone subchondral lucency is an indication of cartilage and bone damage which is best treated with arthrosco

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01598.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SummaryThe rapid development of software and technology now allows a large amount of diagnostic information to be obtained from a computed tomographic examination. This imaging technique can also be usefully applied to the horse, given appropriate premises and a custom built table for accurate positioning. Computed tomography of the skull has considerable advantages over other techniques, as structures are viewed without superimposition. Fifteen cases are used to demonstrate how through high image quality (precise detail, reduction in artefacts) and objective measurement of density, various pathological changes can be analysed and exact diagnoses achieved. In particular, short measurement and examination times allow preoperative imaging under general anaesthesia giving significant information to assist subsequent surgery.

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01599.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SummaryThe density and distribution of MHC Class II positive cells and subpopulations of lymphocytes were studied in the endometrium of genitally normal mares and mares susceptible to endometritis. In genitally normal mares, more MHC Class II positive cells were present in the epithelium andstratum compactumduring oestrus than dioestrus. Significantly more CD4+ and CD8+ lymphocytes were present in thestratum compactumthan in thestratum spongiosum.CD4+ lymphocytes were present in greater numbers than CD8+ lymphocytes in thestratum compactumbut approximately equal numbers were present in thestratum spongiosumand in lymphoid aggregates. Occasional CD4+ and CD8+ cells were seen in the luminal and glandular epithelium. Infrequently, B cells were present in the endometrium and were not observed in the epithelium. Numbers of T and B cells did not appear to be affected by cycle stage. In mares with endometritis, the densities of CD4+, CD8+ and B cells were significantly increased. Large aggregates of lymphoid cells which contained approximately twice as many CD4+ cells as CD8+ cells were present in the endometrium of these mares and all 3 subclasses of lymphocyte were seen occasionally in luminal and glandular epithelium.

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01600.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SummaryTen horses with partial or total retinal detachment were investigated using light and electron microscopy (TEM, SEM). Several lesions were observed and compared with normal retinal morphology. Three weeks after the initial retinal detachment, hypertrophy of the pigment epithelium with transformation of the apical microvilli could be observed. The lesions were accompanied by progressive degeneration and atrophy of the sensory retina, starting at the photoreceptor outer segments. Hypertrophy of Müller cells was a concomitant finding. Retinal detachment represents a sequel either to inflammatory processes or trauma

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01601.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SummaryThe V̇O2maxin racehorses is approximately double that of elite human athletes and the rate of increase in V̇O2at the onset of high intensity exercise is much greater than in man. The kinetics of gas exchange are affected by a warm‐up prior to exercise in humans, there being a greater aerobic contribution to high intensity exercise after warm‐up. Our hypothesis was that a warm‐up would increase aerobic energy delivery in racehorses during high intensity exercise. Thirteen fit Standardbred racehorses ran to fatigue at 115% of V̇O2maxon a treadmill at 10% slope. Prior to acceleration, horses were exercised either for 5 min at 50%V̇O2maxfollowed by 5 min walk, or walked for 2 min. Samples of expired gas were collected every 10 s during the run for determination of V̇O2and V̇CO2and measurement of maximal accumulated oxygen deficit (MAOD). Blood lactate concentration was measured 5 min post exercise. We found that with a warm‐up, horses had faster kinetics of gas exchange and a greater proportion of their total energy requirement was supplied by aerobic sources. The aerobic contribution to total energy requirement with and without warm‐up was, respectively, 79.3 ± 1.0% and 72.4 ± 1.7% (P<0.01). There was also a higher MAOD (P<0.01) in horses that had not been given a warm‐up (mean ± s.e.m. 34.7 ± 2.6 and 47.3 ± 2.6 ml O2eq/kg bwt with and without a warm‐up respectively). However, there were no significant differences in total run time or estimated total energy expenditure between the 2 protocols. We concluded that during high intensity exercise to fatigue lasting 1 to 2 min, more than 70% of energy supply is from aerobic energy sources and that this contribution is even greater when the horses

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01602.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SummaryPlasma and urinary concentrations of procaine and the duration of response to procaine after its administration as a local anaesthetic to horses were studied. Following injection of a clinical dose of procaine HCl (80 mg), the concentration of procaine in plasma was less than the lower limit of quantitation and unsuitable for threshold determination. Therefore, the urinary concentration of procaine was determined after injection of a dose of 5 mg procaine HCl, the highest no‐effect dose (HNED) of this agent. Free unconjugated procaine in equine urine reached a peak concentration of 23.7 ng/ml, while total (unconjugated plus conjugated) procaine peaked at 37.9 ng/ml (mean urine pH of 8.5). Because a basic drug may concentrate substantially in acidic urine, a threshold concentration of 25 ng/ml of unconjugated procaine is a reasonable and conservative threshold for procaine at this time.Horses were administered abaxial sesamoid blocks containing 2% procaine HCl (40, 80, 160 and 320 mg) and 2% procaine HCl (40 and 320 mg) with epinephrine (1:100,000) in local anaesthetic experiments. There was a significant local anaesthetic (LA) effect for all doses of procaine HCl with the duration of effect ranging from 30 min (40 mg) to 60 min (320 mg). The addition of epinephrine significantly increased the duration of local anaesthesia to 180 min for a 40 mg dose and 420 min for a 320 mg dose. Because epinephrine may extend the duration of local anaesthesia beyond a reasonable period of confinement for horses before the starting time of a race, the increased LA effect following the addition of epinephrine to procaine has regulatory significanc

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01603.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SummaryStrains in the superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), accessory ligament of the deep digital flexor muscle (inferior check ligament [ICL]) and theinterosseus mediusmuscle (suspensory ligament [SL]) in the right forelimb of 5 ponies were measured using mercury‐in‐silastic strain gauges a few hours after implantation. Tendon strains were recorded at the walk with normal flat shoes, egg‐bar shoes, a 7° increased hoof angle accomplished by application of a heel‐wedge and a 7° decreased hoof angle using a toe‐wedge, consecutively. Ground reaction forces were recorded with all 4 shoe types preoperatively and with flat shoes post operatively.The strain patterns of the SDFT, DDFT and SL showed a rapid increase at the beginning of the stance phase, followed by a plateau with a small incline or decline and a rapid decrease at the end of the stance phase. The SDFT had its maximal strain in the first half of the stance phase in all ponies. The DDFT and SL reached their maximal strain in the first half of the stance phase in 2 ponies and in the second half of the stance phase in the other 3 ponies. The ICL was strained maximally in the second half of the stance phase in all ponies.Averaged over all 5 ponies, the maximal strains in the SDFT, DDFT, ICL and SL with normal flat shoes were 2.4, 1.3, 5.4 and 3.7%, respectively. If an egg‐bar was applied the mean peak strain in the DDFT was 0.13% lower and strain in the SL was 0.22% higher. With a heel‐wedge, strain decreased in the DDFT and ICL (0.19% and 0.4%, respectively) and increased by 0.24% in the SL. A toe‐wedge increased strain in the ICL by 0.8%. All changes mentioned were statistically significant (P<0.1).The changes in tendon strain as a result of different types of shoeing correlated with changes in calculated torque's of the ground reaction force acting on

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01604.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

SummaryStrains in the tendons of them. flexor digitalis superficialis(superficial digital flexor, SDFT) andm. flexor digitalis profundus(deep digital flexor, DDFT) tendons, the accessory ligament of the deep digital flexor muscle (inferior check ligament, ICL) and them. interosseus medius(suspensory ligament, SL) of 5 ponies were recorded at the walk and trot using mercury‐in‐silastic strain gauges (MISS), on a hard surface (brick pavement) and on sand. The horses were shod with normal, flat shoes.On pavement, strain in the SDFT, DDFT and SL increased significantly from the walk (2.19%, 1.15% and 3.36%, respectively) to the trot (4.15%, 1.70% and 5.78%, respectively), but that in the ICL did not change significantly (5.36% at the walk, 4.88% at the trot). Strains in the ICL and SL were higher on pavement than on sand (P<0.1) and strains in the SDFT and DDFT were not significantly different. Tendon strain in the SDFT and SL, but not in the ICL and DDFT, increased (P<0.1) in a pony at the walk on pavement with a rider.Post mortemloading of the same instrumented limbs revealed that the metacarpophalangeal joint could be further extended when the elbow joint was extended. Thein vitrotendon strain was different from thatin vivo, implying that results fromin vitrolimb loading tests have only limited value for assessing tendon functioningin v

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1996.tb01605.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY