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Abstract

Objective—To characterize pattens of removal and evaluate the associations among culling because of lameness and sow productivity traits among culled gilts and sows.

Design—Cross-sectional study.

Sample Population—Data from a convenience sample of 11 farms pertaining to the removal of 51,795 gilts and sows from January 1991 to December 2002. Mean culling and mortality (death and euthanasia) rates for all inventoried gilts and sows ranged from 23% to 50% and 4.7% to 9.5%, respectively.

Procedure—An analysis of categories of removal (cull, death, or euthanasia) and reasons for removal of gilts and sows was performed. Multivariate logistic regression was used to determine associations among culling because of lameness and sow productivity traits among culled gilts and sows.

Results—Among sows that were removed, the proportion of parity ≥ 1 sows that died (both death and euthanasia) was > 3 times the proportion of parity ≥ 1 sows that were culled within 20 days after farrowing. Among lame sows that were removed, the proportion of parity ≥ 1 sows that died (death and euthanasia) was higher than the proportion of parity ≥ 1 sows that were culled within 20 days after farrowing. Among sows that were removed, the proportion of sows that died (deaths and euthanasia) was higher during lactation than nonlactation. This was also observed among lame sows that were removed.

Conclusions and Clinical Relevance—The proportion of death among removed sows, especially lame sows, was higher during lactation than nonlactation. Results indicated that risk of death is not the same for sows throughout their lifetime. (J Am Vet Med Assoc 2005;226:956–961)

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To compare a sensor-based accelerometer-gyroscopic (A-G) system with a video-based motion analysis system (VMAS) technique for detection and quantification of lameness in horses.

Animals—8 adult horses.

Procedure—2 horses were evaluated once, 2 had navicular disease and were evaluated before and after nerve blocks, and 4 had 2 levels of shoe-induced lameness, alternatively, in each of 4 limbs. Horses were instrumented with an accelerometer transducer on the head and pelvis, a gyroscopic transducer on the right forelimb and hind feet, and a receiver-transmitter. Signals from the A-G system were collected simultaneously with those from the VMAS for collection of head, pelvis, and right feet positions with horses trotting on a treadmill. Lameness was detected with an algorithm that quantified lameness as asymmetry of head and pelvic movements. Comparisons between the A-G and VMAS systems were made by use of correlation and agreement (κ value) analyses.

Results—Correlation between the A-G and VMAS systems for quantification of lameness was linear and high ( r 2 = 0.9544 and 0.8235 for forelimb and hind limb, respectively). Quantification of hind limb lameness with the A-G system was higher than measured via VMAS. Agreement between the 2 methods for detection of lameness was excellent (κ = 0.76) for the forelimb and good (κ = 0.56) for the hind limb.

Conclusions and Clinical Relevance—The A-G system detected and quantified forelimb and hind limb lameness in horses trotting on the treadmill. Because the data are collected wirelessly, this system might be used to objectively evaluate lameness in the field. ( Am J Vet Res 2004;65:665–670)

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in American Journal of Veterinary Research

Abstract

Objective—To investigate continuous wavelet transformation and neural network classification of gait data for detecting forelimb lameness in horses.

Animals—12 adult horses with mild forelimb lameness.

Procedure—Position of the head and right forelimb foot, metacarpophalangeal (ie, fetlock), carpal, and elbow joints was determined by use of kinematic analysis before and after palmar digital nerve blocks. We obtained 8 recordings from horses without lameness, 8 with right forelimb lameness, and 8 with left forelimb lameness. Vertical and horizontal position of the head and vertical position of the foot, fetlock, carpal, and elbow joints were processed by continuous wavelet transformation. Feature vectors were created from the transformed signals and a neural network trained with data from 6 horses, which was then tested on the remaining 2 horses for each category until each horse was used twice for training and testing. Correct classification percentage (CCP) was calculated for each combination of gait signals tested.

Results—Wavelet-transformed vertical position of the head and right forelimb foot had greater CCP (85%) than untransformed data (21%). Adding data from the fetlock, carpal, or elbow joints did not improve CCP over that for the head and foot alone.

Conclusions and Clinical Relevance—Wavelet transformation of gait data extracts information that is important for the detection and differentiation of forelimb lameness of horses. All of the necessary information to detect lameness and differentiate the side of lameness can be obtained by observation of vertical head movement in concert with movement of the foot of 1 forelimb. (Am J Vet Res 2003;64:1376–1381)

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in American Journal of Veterinary Research

Abstract

Objective—To identify hind limb and pelvic kinematic variables that change in trotting horses after induced lameness of the distal intertarsal and tarsometatarsal joints and after subsequent intra-articular administration of anesthetic.

Animals—8 clinically normal adult horses.

Procedure—Kinematic measurements were made before and after transient endotoxin-induced lameness of the distal intertarsal and tarsometatarsal joints and after intra-articular administration of anesthetic. Fourteen displacement and joint angle (metatarsophalangeal [fetlock] and tarsal joints) measurements were made on the right hind limb, sacrum, and the right and left tubera coxae. Kinematic measurements were compared by general linear models, using a repeated measures ANOVA. Post hoc multiple comparisons between treatments were evaluated with a Fisher least squared difference test at α = 0.05.

Results—After lameness induction, fetlock and tarsal joint extension during stance decreased, fetlock joint flexion and hoof height during swing increased, limb protraction decreased, and vertical excursion of the tubera coxae became more asymmetric. After intra-articular administration of anesthetic, limb protraction returned to the degree seen before lameness, and vertical excursion of the tubera coxae became more symmetric.

Conclusions and Clinical Relevance—Increased length of hind limb protraction and symmetry of tubera coxae vertical excursion are sensitive indicators of improvement in tarsal joint lameness. When evaluating changes in tarsal joint lameness, evaluating the horse from the side (to assess limb protraction) is as important as evaluating from the rear (to assess pelvic symmetry). (Am J Vet Res 2000;61:1031–1036)

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in American Journal of Veterinary Research

Abstract

Objective—To ascertain the effectiveness of evaluating ground reaction forces (GRFs) at velocities during walking and trotting in dogs with naturally occurring lameness and determine whether walking would provide sufficient motion to adequately characterize GRFs with respect to trotting.

Animals—29 dogs with a naturally occurring tear of the cranial cruciate ligament.

Procedure—Dogs were walked and trotted over a force platform, and GRFs were recorded during the stance phase. Correlation was used to assess the agreement between walking and trotting for GRF. The coefficient of variation was calculated to assess the relative variation of outcome variables among the gaits. Group means for walking GRF were compared between dogs that trotted and that failed to trot.

Results—GRFs during walking and trotting were highly correlated. The coefficient of variation was smaller for GRFs during walking than during trotting. Dogs that failed to trot had significantly smaller mean values of peak vertical force and vertical impulse during walking, compared with values for dogs that were able to trot.

Conclusions and Clinical Relevance—Either velocity is acceptable for GRF evaluation in dogs. Mean GRF during walking was significantly different between dogs that could and could not trot, principally because dogs with the most severe lameness failed to trot. These dogs would be eliminated from a clinical study, and thus, that study would become biased toward dogs that were less lame. In that situation, differences between interventions may be less pronounced, because they would be evaluated on dogs with less lameness. (Am J Vet Res 2003;64: 1479–1481)

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in American Journal of Veterinary Research

Abstract

Objective—To identify types of musculoskeletal problems associated with lameness or poor performance in horses used for barrel racing.

Design—Retrospective case series.

Animals—118 horses.

Procedure—Medical records were reviewed for information on signalment, history, physical and lameness examination findings, diagnostic tests performed, diagnosis, and treatment.

Results—Most horses were examined because of lameness (n = 72 [61%]) rather than poor performance (46 [39%]), but owner complaint was not significantly associated with age or body weight of the horse. The most common performance change was refusal or failure to turn properly around the first barrel (19/46 [41%]). The right forelimb (n = 57 [48%]) was most commonly affected, followed by the left forelimb (51 [43%]), the left hind limb (31 [26%]), and the right hind limb (25 [21%]). In 31 horses (26%), both forelimbs were affected, and in 6 (5%), both hind limbs were affected. The most common musculoskeletal problems were forelimb foot pain only (n = 39 [33%]), osteoarthritis of the distal tarsal joints (17 [14%]), suspensory ligament desmitis (15 [13%]), forelimb foot pain with distal tarsal joint osteoarthritis (11 [9%]), and bruised feet (10 [8.5%]). In 81 (69%) horses, the affected joint was treated with intra-articular medications.

Conclusions and Clinical Relevance—Results suggest that in horses used for barrel racing that are examined because of lameness or poor performance, the forelimbs are more likely to be affected than the hind limbs, with forelimb foot pain and osteoarthritis of the distal tarsal joints being the most common underlying abnormalities. (J Am Vet Med Assoc 2005; 227:1646–1650)

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in Journal of the American Veterinary Medical Association

History A 13-year-old 626-kg (1,377-lb) Georgian Grande gelding used for upper-level dressage was referred for evaluation because of left hind limb lameness that had progressed from mild lameness noticed approximately 4 weeks before referral

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the prevalence of cranial cruciate ligament rupture (CCLR) in dogs with lameness previously attributed to canine hip dysplasia (CHD).

Design—Retrospective study.

Animals—369 client-owned dogs.

Procedures—Hospital medical records from 1994 to 2003 were reviewed for dogs in which the referring veterinarian had diagnosed hip dysplasia or hip pain. Dogs were designated as having hind limb lameness because of partial or complete CCLR or CHD.

Results—8% of dogs were sexually intact females, 43% were spayed females, 14% were sexually intact males, and 35% were castrated males. Mean age was 3.8 years (range, 3 months to 15 years). The most common breeds were the Labrador Retriever (21%), German Shepherd Dog (13%), and Golden Retriever (11%). The prevalence of CCLR as the cause of hind limb lameness was 32% (95% confidence interval, 27.2% to 36.8%). The distribution of CCLR among hind limbs was left (29%), right (28%), and bilateral (43%). Of 119 dogs with CCLR, 94% had concurrent radiographic signs of CHD, 92% had stifle joint effusion, and 81% had a cranial drawer sign.

Conclusions and Clinical Relevance—On the basis of the high prevalence of CCLR in dogs referred for lameness because of CHD, it is important to exclude other sources of stifle joint disease before making recommendations for treatment of CHD. (J Am Vet Med Assoc 2005;227:1109–1111)

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine whether iatrogenic hemarthrosis of the metacarpophalangeal joint could be used as a model for temporary reversible joint pain in horses.

Animals—8 adult horses.

Procedure—Each horse was evaluated on a treadmill before and after injection of 1 metacarpophalangeal joint with 10 mL of autogenous blood. Horses were evaluated subjectively and objectively by use of a computerized force measurement system at intervals until lameness abated. The mean force difference between injected and noninjected limbs at all time periods after injection was compared with the difference between limbs at baseline. From each horse, synovial fluid samples collected before and 24 hours and 30 days after injection were analyzed for total protein concentration and cell type and number. Venous blood samples were collected before and 6 and 24 hours after injection for assessment of plasma cortisol concentration.

Results—For 24 hours after injection, the mean force difference between injected and noninjected limbs was significantly increased over baseline. The greatest force difference was detected after 2 and 4 hours. Baseline and 24-hour force data were not significantly different. Compared with baseline values, synovial fluid protein concentration and nucleated cell and RBC counts were increased significantly at 24 hours after injection but were not different at 30 days after injection. No significant changes in plasma cortisol concentration were detected at any time point.

Conclusions and Clinical Relevance—In horses, iatrogenic hemarthrosis of the metacarpophalangeal joint appears to induce temporary reversible lameness with a mild to moderate degree of synovitis. (Am J Vet Res 2005;66:1084–1089)

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in American Journal of Veterinary Research

History A 13-month-old 29.3-kg spayed female German Shepherd Dog was referred for evaluation of a left hind limb lameness. Clinical signs of progressive worsening lameness began at 5 months of age and were more severe on the left side. There

Full access
in Journal of the American Veterinary Medical Association