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Kenneth W. Hinchcliff - One of the best experts on this subject based on the ideXlab platform.
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muscle injury and antioxidant status in Sled Dogs competing in a long distance Sled Dog race
Equine and Comparative Exercise Physiology, 2004Co-Authors: Kenneth W. Hinchcliff, P D Constable, Robert A. DisilvestroAbstract:Exercise is associated with an increase in the production of oxidants that may be instrumental in the development of exertional rhabdomyolysis. We speculated that participation in a long-distance Sled race would alter antioxidant capacity of Dogs, in conjunction with increases in indices of rhabdomyolysis. The objective was to determine the effect of participation in a long-distance Sled Dog race on antioxidant capacity and plasma creatine kinase (CK) activity in Sled Dogs. This was a prospective, longitudinal study on a convenience sample of 57 Alaskan Sled Dogs participating in a 1600 km Sled Dog race. Blood samples were collected before racing (31 Dogs) and after racing (39 Dogs) for measurement of plasma vitamin E concentration; CK, aspartate aminotransferase (AST) and caeruloplasmin (CER) activity; and red-blood-cell (RBC) glutathione peroxidase (GPX) and superoxide dismutase (SOD) activity. CER and GPX activities after the race were 26% and 14% lower, respectively, than before racing whereas CK and AST were 300% and 170% greater. There was no change in plasma vitamin E concentration or RBC SOD activity. We conclude that completion of a long-distance Sled Dog race involving prolonged and repeated submaximal exercise results in a reduction in enzymatic antioxidant activity in the blood of Sled Dogs.
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Effects of racing and nontraining on plasma thyroid hormone concentrations in Sled Dogs.
Javma-journal of The American Veterinary Medical Association, 2004Co-Authors: Kenneth W. Hinchcliff, Richard J Piercy, Karin E Schmidt, Stuart L NelsonAbstract:Objective—To determine the effects of racing and nontraining on plasma thyroxine (T4), free thyroxine (fT4), thyroid-stimulating hormone (TSH), and thyroglobulin autoantibody (TgAA) concentrations in Sled Dogs and compare results with reference ranges established for Dogs of other breeds. Design—Cross-sectional study. Animals—122 Sled Dogs. Procedure—Plasma thyroid hormone concentrations were measured before Dogs began and after they finished or were removed from the Iditarod Trail Sled Dog Race in Alaska and approximately 3 months after the race. Results—Concentrations of T4 and fT4 before the race were less than the reference range for nonSled Dogs in 26% and 18% of Sled Dogs, respectively. Immediately after racing, 92% of Sled Dogs had plasma T4 concentrations less than the reference range. Three months after the race, 25% of Sled Dogs had plasma T4 concentrations less than the reference range. For T4, fT4, TSH, and TgAA, significant differences were not detected in samples collected before the race ve...
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vitamin e and exertional rhabdomyolysis during endurance Sled Dog racing
Neuromuscular Disorders, 2001Co-Authors: Richard J Piercy, Kenneth W. Hinchcliff, Gregory A Reinhart, Stuart L Nelson, Karin E Schmidt, Robert A. Disilvestro, Paul S. Morley, Morrie A CraigAbstract:Exertional rhabdomyolysis (ER) is common in Sled Dogs, animals with high energy expenditures that consume high fat (60% of ingested calories) diets. Associations between pre-race plasma [vitamin E] and total antioxidant status (TAS) and risk of developing ER were examined in Dogs competing in the 1998 Iditarod race. Pre-race blood samples were collected from 750 Dogs and a second sample was collected from 158 Dogs withdrawn from the race at various times. Plasma creatine kinase activity was used to identify withdrawn Dogs with ER. There was no association between pre-race plasma [vitamin E] and risk of development of ER. Dogs that developed ER started the race with higher TAS, but when withdrawn, had lower TAS than unaffected Dogs and had similar pre-race [vitamin E] but higher [vitamin E] at time of withdrawal. Hence, the risk of ER in Sled Dogs is not affected by plasma [vitamin E] before the race.
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Effect of distance traveled and speed of racing on body weight and serum enzyme activity of Sled Dogs competing in a long-distance race.
Javma-journal of The American Veterinary Medical Association, 1998Co-Authors: Kenneth W. Hinchcliff, Shaw Lc, Vukich Ns, Karin E SchmidtAbstract:OBJECTIVE: To determine the relationship of serum biochemical values and change in body weight with finishing status (retired from or finished the race), finishing order of a team, and distance traveled for Dogs participating in a long-distance Sled Dog race. ANIMALS: 262 of 848 Dogs that participated in the 1995 Iditarod Trail Sled Dog race. DESIGN: Prospective study. PROCEDURE: Body weight was recorded for 261 Dogs before the race and again when these Dogs retired from or completed the race. Using a nonrandom convenience sample of participating Dogs, blood samples were obtained from 151 Dogs that retired from the race and 111 Dogs that completed the race. RESULTS: Serum biochemical indices of skeletal muscle damage were significantly higher in Dogs retiring during the first 500 miles of the race than in Dogs retiring in the last 638 miles or finishing the race. Serum sodium concentration was less than the reference range in a significantly greater proportion of Dogs that retired from the race than of Dogs that completed the race. There was little relationship between finishing order and serum biochemical values. Dogs completing the race lost a mean of 8.9% of body weight, and amount of weight lost was not related to finishing order. CLINICAL IMPLICATIONS: Results indicated that exertional rhabdomyolysis develops more often in Dogs that retire during the initial 500 miles of a long-distance race, compared with Dogs that complete the race. There is no detectable relationship between the speed with which the race is run (finishing order) and body weight loss or serum biochemical values.
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Metabolizable energy intake and sustained energy expenditure of Alaskan Sled Dogs during heavy exertion in the cold.
American Journal of Veterinary Research, 1997Co-Authors: Kenneth W. Hinchcliff, Gregory A Reinhart, John Burr, C.j. Schreier, R. A. SwensonAbstract:OBJECTIVE: To measure energy expenditures of Alaskan Sled Dogs at rest and during racing under frigid conditions, using the doubly labeled water (DLW) technique. ANIMALS: 18 fit Alaskan Sled Dogs. PROCEDURE: Energy expenditure was measured in 9 Dogs during a 490-km Sled Dog race by use of the DLW technique, whereby Dogs were administered water enriched with nonradioactive isotopes of hydrogen and oxygen. Energy intake was determined by dietary analysis. Changes in background abundance of the isotopes 2H and 18O were monitored in 5 Dogs that did not receive isotope-enriched water. RESULTS: Dogs completed the 490-km race at an average speed of 7 km/h at ambient temperature of -35 to -10 C. Total energy expenditure, measured by the DLW technique, was 47,100 +/- 5,900 kJ/d (4,400 +/- 400 kJ.kg-0.75/d), and metabolizable energy intake was 44,600 kJ/d (4,100 kJ.kg-0.75/d) during the 70-hour race. CONCLUSIONS: The sustained metabolic rate for these Sled Dogs during racing was extraordinarily high for a large mammal. This study validated use of the DLW technique in Dogs with exceptionally high energy expenditure associated with prolonged exercise in the cold.
Anna Bajer - One of the best experts on this subject based on the ideXlab platform.
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the risk of vector borne infections in Sled Dogs associated with existing and new endemic areas in poland part 2 occurrence and control of babesiosis in a Sled Dog kennel during a 13 year long period
Veterinary Parasitology, 2014Co-Authors: Anna Bajer, Ewa J Mierzejewska, Anna Rodo, Renata WelcfaleciakAbstract:Abstract The achievements of Sled Dogs in competitions depend both on their training and on their health. Vector-borne infections may lead to anemia, affect joints or heart muscles or even cause death. Canine babesiosis is an emerging, quickly spreading tick-borne disease in Central Europe. Over a 13-year period (2000–2012) the occurrence of babesiosis cases was analyzed in one Sled Dog kennel situated in Kury, a village near Tluszcz (N 52°24′56.78″, E 21°30′37.55″) in Central Poland. Twenty cases/episodes of babesiosis were noted among the 10–12 Dogs living in the kennel. In 2000–2004, no cases of babesiosis were noted; the first two cases were noted in April 2005. Since that time, only one Dog remained uninfected; 6 Dogs were infected once, 3 Dogs demonstrated symptoms of babesiosis twice, one Dog was infected three times and one Dog had it five times. Babesiosis appeared in Spring and Autumn, despite the application of anti-tick treatment. No fatal cases were recorded, but in one case a splenectomy was performed due to splenomegaly and spleen rupture. Additionally, the abundance of the main Babesia canis vector, the Dermacentor reticulatus tick, was estimated and monitored during a 4-year period (2008–2012) close to the Dog kennel. The abundance of questing ticks was high in 2008 and 2009, but dropped by 10-fold between 2010 and 2012, when the abandoned meadow was cut and used as horse pasture by the local farmer. The regular occurrence, typical seasonal pattern and identification of B. canis DNA in questing tick from this locality confirmed the establishment of a new hyper enzootic region for canine babesiosis. The effectiveness and schedule of applied preventive measures were discussed.
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The risk of vector-borne infections in Sled Dogs associated with existing and new endemic areas in Poland: Part 1: A population study on Sled Dogs during the racing season.
Veterinary parasitology, 2014Co-Authors: Anna Bajer, Ewa J Mierzejewska, Anna Rodo, Malgorzata Bednarska, Maciej Kowalec, Renata Welc-falęciakAbstract:The achievements of Sled Dogs in competitions depend both on their training and on their health. Vector-borne infections may lead to anaemia, affect joints or heart muscle or even cause death. Between December 2009 and October 2010, one hundred and twenty six individual blood samples were collected from 26 Sled Dog kennels situated in different regions of Poland. The majority of samples were taken during the racing season (winter 2009/10). The prevalences of 3 vector-borne infections- including 2 'old pathogens' Anaplasma phagocytophilum and Babesia canis, and 'new pathogen' Hepatozoon canis-were estimated in Sled Dogs using PCR and nested PCR. Additionally, 25 serum samples originating from a subset of 3 kennels situated in a tick-borne encephalitis (TBE) endemic area (Mazowiecki region), were tested for antibodies against the tick-borne encephalitis virus (TBEV). Because of the recently reported occurrence of Dirofilaria repens in Central Poland and that of fatal cases of unknown aetiology in two of the kennels, blood samples collected from Dogs at these kennels in 2010 and in February-May 2013 and from two unaffected kennels were checked for evidence of presence of this parasite. Babesia canis DNA was detected in 11 Sled Dogs (4 with clinical babesiosis, 7 asymptomatic; 8.7%) inhabiting mainly endemic regions of Poland (9/11 cases). Three serum samples originating from one location tested positive for TBEV antibodies (total seroprevalence: 3/25=12%, local seroprevalence: 3/12=25%). The risk of TBEV infection was associated with previous B. canis infections. Dirofilaria repens DNA was detected in 15 Dogs (44%). Prevalence was especially high in two Sled Dog kennels situated near Grodzisk Mazowiecki (50-57%). No blood samples tested positive for A. phagocytophilum or H. canis DNA. The present study has established that the prevalence of vector-borne pathogens in working Sled Dogs is significant in the endemic regions and has justified the important role of surveillance of reservoir hosts in the epidemiology of TBE. Our results emphasize the need for regular monitoring for the presence of D. repens.
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babesia canis and tick borne encephalitis virus tbev co infection in a Sled Dog
Annals of Agricultural and Environmental Medicine, 2013Co-Authors: Anna Bajer, Ewa J Mierzejewska, Anna Rodo, Renata Welcfaleciak, Malgorzata Bednarska, Veterinary DiagnosticsAbstract:Introduction and objectives. Sporting Dogs, including Sled Dogs, are particularly prone to tick-borne infection either due to training/racing in forest areas or through visits to endemic areas. The aim was to present tick-borne infections in a 6-Dog racing team after a race in Estonia. Materials and methods. On the 4th day after return to Poland, the first Dog presented with babesiosis symptoms and was diagnosed and treated accordingly. Next morning, the Dog showed neurological symptoms and was diagnosed with tickborne encephalitis (TBE). Diagnosis was confirmed by a high level of IgG antibodies (922 IU/ml), detected in serum 3 months later. The second Dog presented with babesiosis symptoms on the 7th day after return. Babesia DNA was extracted from blood, amplified and sequenced to answer the question of whether the Dogs became infected during the race in Estonia or in Poland. Results and conclusions. Sequencing of a fragment of Babesia 18S rDNA revealed that these two isolates were identical to one another and closely related to the B. canis sequence originally isolated from the Dog and Dermacentor reticulatus ticks in Poland. Thus, this is the first confirmed case of B.canis and TBEV co-infection and first confirmed case of TBE in a Dog in Poland.
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Risk factors and control of intestinal parasite infections in Sled Dogs in Poland.
Veterinary parasitology, 2010Co-Authors: Anna Bajer, Malgorzata Bednarska, Anna RodoAbstract:Training and racing constitute serious challenges for working Sled Dogs. Attainment of the highest levels of stamina and speed are possible only by completely healthy Dogs. Infections with nematodes as whipworm Trichuris sp. or hookworms Uncinaria/Ancylostoma can significantly reduce the fitness of working Dogs leading to anemia or even to death. In the middle of the racing season, between December 2009 and April 2010, 108 individual fecal samples were collected from 25 Sled Dog kennels situated in different regions of Poland. Saturated salt flotation was performed for helminth egg detection. The immunofluorescent assay MeriFluor Cryptosporidium/Giardia and nested PCRs on 18S rRNA (Cryptosporidium spp.) and TPI gene (Giardia spp.) were carried out for detection of intestinal protozoa. Overall prevalence of 6 species of intestinal parasites was 68% in Sled Dogs (73/108). In 51 samples the eggs of a single species of helminth were detected (47%), two nematode species were detected in 13%, three species of nematodes were found in two Dogs. The most prevalent helminths were the hookworms Uncinaria/Ancylostoma-identified in 36% of kennels, and in 34% of Sled Dogs. Toxocara eggs were detected in 36% of kennels, in 17% of Dogs. Trichuris sp. eggs were found in 20% of kennels (5/25), in 13% of Dogs. Cysts/oocysts of intestinal protozoa were detected in 31% of Sled Dogs. The most prevalent was Giardia spp. infection-in 54% of kennels [13/24], in 28% of Dogs. Cryptosporidium spp. infections were identified in 37.5% of kennels [9/24], in 13% of Dogs. Two sequenced Giardia isolates presented 100% homology with G. intestinalis Assemblage C isolate (AY228641.1), specific for Dogs. A range of factors was shown to affect the prevalence of intestinal parasites in Sled Dogs. The highest prevalence of parasites was found among Dogs from large kennels (housing >3 Dogs), in Dogs less than 2 years old, and in kennels, where prophylactic treatment was carried out 1-4 times a year. The present study has demonstrated a high prevalence of intestinal parasites in working Sled Dogs in Poland, including the zoonotic human pathogens Toxocara or Cryptosporidium.
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Babesia canis and other tick-borne infections in Dogs in Central Poland.
Veterinary Parasitology, 2009Co-Authors: Renata Welc-falęciak, Anna Rodo, Edward Siński, Anna BajerAbstract:Abstract Vector-borne infections constitute increasing health problem in Dogs worldwide, including Sled Dogs, dramatically decreasing the fitness of working Dogs and even leading to death. In the period 2006–2008 eighty-two blood samples were collected from eight Sled Dog kennels in Central Poland. The prevalence of four vector-borne infections ( Babesia canis , Bartonella sp., Anaplasma / Ehrlichia and Borrelia burgdorferi ) was estimated in 82 Sled Dogs using PCR and nested PCR for diagnosis and the same methods were used to identify the vector-borne pathogens in 26 Dogs presenting at veterinary clinics with symptoms of vector-borne diseases. None of four studied vector-borne pathogens was detected in samples originating from veterinary clinics. Among the remaining 82 Dogs B. canis infections were confirmed in three Dogs undergoing treatment for babesiosis. The DNA of tick-borne pathogens was also found among 22 (27.8%) of the 79 apparently healthy Dogs, including 20 cases of B. canis infection (25.3%), one case of B. burgdorferi s.l. infection and one case of Anaplasma phagocytophilum infection. No evidence of Bartonella spp. and Ehrlichia canis infections were found in this set of samples. Sequencing of a Babesia fragment of 18S rDNA amplified from acute ( n = 5) and asymptomatic ( n = 5) cases revealed that all isolates were identical to the Babesia canis canis sequence, originally isolated from Dermacentor reticulatus ticks in Poland. A range of factors was shown to affect the distribution of babesiosis in Sled Dogs. The data are also discussed in respect to the health risk factors generated by asymptomatic B. canis infections and the efficiency of chemoprophylaxis measures taken by Sled Dog owners.
Renata Welcfaleciak - One of the best experts on this subject based on the ideXlab platform.
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the risk of vector borne infections in Sled Dogs associated with existing and new endemic areas in poland part 2 occurrence and control of babesiosis in a Sled Dog kennel during a 13 year long period
Veterinary Parasitology, 2014Co-Authors: Anna Bajer, Ewa J Mierzejewska, Anna Rodo, Renata WelcfaleciakAbstract:Abstract The achievements of Sled Dogs in competitions depend both on their training and on their health. Vector-borne infections may lead to anemia, affect joints or heart muscles or even cause death. Canine babesiosis is an emerging, quickly spreading tick-borne disease in Central Europe. Over a 13-year period (2000–2012) the occurrence of babesiosis cases was analyzed in one Sled Dog kennel situated in Kury, a village near Tluszcz (N 52°24′56.78″, E 21°30′37.55″) in Central Poland. Twenty cases/episodes of babesiosis were noted among the 10–12 Dogs living in the kennel. In 2000–2004, no cases of babesiosis were noted; the first two cases were noted in April 2005. Since that time, only one Dog remained uninfected; 6 Dogs were infected once, 3 Dogs demonstrated symptoms of babesiosis twice, one Dog was infected three times and one Dog had it five times. Babesiosis appeared in Spring and Autumn, despite the application of anti-tick treatment. No fatal cases were recorded, but in one case a splenectomy was performed due to splenomegaly and spleen rupture. Additionally, the abundance of the main Babesia canis vector, the Dermacentor reticulatus tick, was estimated and monitored during a 4-year period (2008–2012) close to the Dog kennel. The abundance of questing ticks was high in 2008 and 2009, but dropped by 10-fold between 2010 and 2012, when the abandoned meadow was cut and used as horse pasture by the local farmer. The regular occurrence, typical seasonal pattern and identification of B. canis DNA in questing tick from this locality confirmed the establishment of a new hyper enzootic region for canine babesiosis. The effectiveness and schedule of applied preventive measures were discussed.
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babesia canis and tick borne encephalitis virus tbev co infection in a Sled Dog
Annals of Agricultural and Environmental Medicine, 2013Co-Authors: Anna Bajer, Ewa J Mierzejewska, Anna Rodo, Renata Welcfaleciak, Malgorzata Bednarska, Veterinary DiagnosticsAbstract:Introduction and objectives. Sporting Dogs, including Sled Dogs, are particularly prone to tick-borne infection either due to training/racing in forest areas or through visits to endemic areas. The aim was to present tick-borne infections in a 6-Dog racing team after a race in Estonia. Materials and methods. On the 4th day after return to Poland, the first Dog presented with babesiosis symptoms and was diagnosed and treated accordingly. Next morning, the Dog showed neurological symptoms and was diagnosed with tickborne encephalitis (TBE). Diagnosis was confirmed by a high level of IgG antibodies (922 IU/ml), detected in serum 3 months later. The second Dog presented with babesiosis symptoms on the 7th day after return. Babesia DNA was extracted from blood, amplified and sequenced to answer the question of whether the Dogs became infected during the race in Estonia or in Poland. Results and conclusions. Sequencing of a fragment of Babesia 18S rDNA revealed that these two isolates were identical to one another and closely related to the B. canis sequence originally isolated from the Dog and Dermacentor reticulatus ticks in Poland. Thus, this is the first confirmed case of B.canis and TBEV co-infection and first confirmed case of TBE in a Dog in Poland.
P D Constable - One of the best experts on this subject based on the ideXlab platform.
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muscle injury and antioxidant status in Sled Dogs competing in a long distance Sled Dog race
Equine and Comparative Exercise Physiology, 2004Co-Authors: Kenneth W. Hinchcliff, P D Constable, Robert A. DisilvestroAbstract:Exercise is associated with an increase in the production of oxidants that may be instrumental in the development of exertional rhabdomyolysis. We speculated that participation in a long-distance Sled race would alter antioxidant capacity of Dogs, in conjunction with increases in indices of rhabdomyolysis. The objective was to determine the effect of participation in a long-distance Sled Dog race on antioxidant capacity and plasma creatine kinase (CK) activity in Sled Dogs. This was a prospective, longitudinal study on a convenience sample of 57 Alaskan Sled Dogs participating in a 1600 km Sled Dog race. Blood samples were collected before racing (31 Dogs) and after racing (39 Dogs) for measurement of plasma vitamin E concentration; CK, aspartate aminotransferase (AST) and caeruloplasmin (CER) activity; and red-blood-cell (RBC) glutathione peroxidase (GPX) and superoxide dismutase (SOD) activity. CER and GPX activities after the race were 26% and 14% lower, respectively, than before racing whereas CK and AST were 300% and 170% greater. There was no change in plasma vitamin E concentration or RBC SOD activity. We conclude that completion of a long-distance Sled Dog race involving prolonged and repeated submaximal exercise results in a reduction in enzymatic antioxidant activity in the blood of Sled Dogs.
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plasma thyroid hormone concentrations in Dogs competing in a long distance Sled Dog race
Journal of Veterinary Internal Medicine, 2003Co-Authors: D L Panciera, K W Hinchcliff, J Olson, P D ConstableAbstract:: Plasma thyroxine (T4), 3,5,3'-triiodothyronine (T3), total protein, and albumin concentrations were measured in 15 Dogs both before and after completion, and in an additional 16 Dogs before and 24 Dogs after completion, of a long-distance Sled Dog race. The plasma T4 concentration (mean +/- SD) decreased significantly from 18.2 +/- 5.4 nmol/L before to 14.3 +/- 3.5 nmol/L after the race in Dogs evaluated at both times and decreased significantly from 21.8 +/- 10.5 nmol/L before to 15.8 +/- 4.9 nmol/L after the race in Dogs sampled only before or only after the race. The mean plasma T3 concentrations in Dogs measured twice decreased significantly from 1.20 +/- 0.48 nmol/L before to 0.74 +/- 0.42 nmol/L after the race, as well as in Dogs measured either before (1.28 +/- 0.36 nmol/L) or after (0.69 +/- 0.28 nmol/L) the race, respectively. Plasma total protein and albumin concentrations decreased significantly after completion of the race. No significant change was noted in 4 control Dogs that did not compete in the race and were tested during a similar time period. The plasma concentrations of T4 and T3 were lower than the normal reference range established for this laboratory in 23 and 39%, respectively, of Alaskan Sled Dogs tested before the race. Plasma thyroid hormone concentrations frequently are below normal in conditioned Alaskan Sled Dogs and are further reduced after prolonged submaximal exercise.
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ELECTROCARDIOGRAPHIC CHARACTERISTICS OF ENDURANCE-TRAINED ALASKAN Sled DogS
Javma-journal of The American Veterinary Medical Association, 1997Co-Authors: Kenneth W. Hinchcliff, Karin E Schmidt, P D Constable, James W. Farris, Robert L. HamlinAbstract:OBJECTIVE: To determine electrocardiographic characteristics of endurance-trained Alaskan Sled Dogs. DESIGN: Case series. ANIMALS: 319 Alaskan Sled Dogs entered to compete in the 1994 Iditarod Trail Sled Dog Race. PROCEDURE: ECG were recorded while Dogs were standing and were analyzed digitally. RESULTS: Amplitudes of P waves (median, 0.40 mV; fifth to 95th percentile range, 0.11 to 0.61 mV) and R waves in lead II (median, 3.02 mV; fifth to 95th percentile range, 1.49 to 4.40 mV) were high; durations of P waves in lead II (median, 61 milliseconds; fifth to 95th percentile range, 36 to 96 milliseconds), QRS complexes (median, 64 milliseconds; fifth to 95th percentile range, 52 to 80 milliseconds), and QT intervals (median, 236 milliseconds; fifth to 95th percentile range, 208 to 277 milliseconds) were prolonged. Median value for mean axis of ventricular depolarization was 57 degrees (fifth to 95th percentile range, 19 to 90 degrees). Atrial and ventricular premature depolarizations were observed in 3 (0.9%) and 4 (1.3%) of 319 Dogs, respectively, and paroxysmal ventricular tachycardia was detected in 1 (0.3%). CLINICAL IMPLICATIONS: Results suggest that electrocardiographic characteristics of endurance-trained Alaskan Sled Dogs differ from those reported for nonSled Dogs, probably as a result of effects of endurance training on heart size. Some of these characteristics could be mistaken as evidence of pathologic cardiac hypertrophy.
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Factors associated with finishing status for Dogs competing in a long-distance Sled race.
Javma-journal of The American Veterinary Medical Association, 1996Co-Authors: P D Constable, Kenneth W. Hinchcliff, James W. Farris, Karin E SchmidtAbstract:OBJECTIVE: To determine whether selected factors were associated with finishing status in a long-distance Sled Dog race. DESIGN: Prospective, observational study. ANIMALS: 248 Dogs participating in the 1994 Iditarod trail Sled race that were members of 13 teams that finished the race. Dogs were not selected randomly, but were members of teams that were easily accessible for examination before the race. The proportion of teams that were examined that finished the race (14/17) was similar to the proportion of teams that were not examined that finished the race (36/41). PROCEDURE: Age, sex, body conformation (weight, length, and thoracic width and circumference), cardiac variables (heart rate, natural logarithm of heart period variance, PR interval, QRS duration, QT index, R wave amplitude in leads II and V3, mean electrical axis, presence of cardiac arrhythmias suggestive of myocardial disease), and athletic ranking as assessed by the musher were compared between Dogs that finished the race (n = 128) and Dogs that did not finish (n = 120). RESULTS: The only factor found to differ significantly (P < 0.05) between finishers and nonfinishers was athletic ranking as assessed by the musher. Athletic rank and QRS duration or QRS duration normalized for body weight were identified by means of logistic regression as variables associated (P < 0.15) with finishing status. There was a significant (P < 0.0001), but weak (R2 = 0.18), linear relationship between race time and mean QRS duration for each team. CLINICAL IMPLICATIONS: Athletic ranking as assessed by the musher was the most important of the studied variables in determining finishing status, whereas age, sex, body conformation, and body weight were unimportant. Duration of the QRS was of minor importance in determining finishing status.
Karin E Schmidt - One of the best experts on this subject based on the ideXlab platform.
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Effects of racing and nontraining on plasma thyroid hormone concentrations in Sled Dogs.
Javma-journal of The American Veterinary Medical Association, 2004Co-Authors: Kenneth W. Hinchcliff, Richard J Piercy, Karin E Schmidt, Stuart L NelsonAbstract:Objective—To determine the effects of racing and nontraining on plasma thyroxine (T4), free thyroxine (fT4), thyroid-stimulating hormone (TSH), and thyroglobulin autoantibody (TgAA) concentrations in Sled Dogs and compare results with reference ranges established for Dogs of other breeds. Design—Cross-sectional study. Animals—122 Sled Dogs. Procedure—Plasma thyroid hormone concentrations were measured before Dogs began and after they finished or were removed from the Iditarod Trail Sled Dog Race in Alaska and approximately 3 months after the race. Results—Concentrations of T4 and fT4 before the race were less than the reference range for nonSled Dogs in 26% and 18% of Sled Dogs, respectively. Immediately after racing, 92% of Sled Dogs had plasma T4 concentrations less than the reference range. Three months after the race, 25% of Sled Dogs had plasma T4 concentrations less than the reference range. For T4, fT4, TSH, and TgAA, significant differences were not detected in samples collected before the race ve...
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vitamin e and exertional rhabdomyolysis during endurance Sled Dog racing
Neuromuscular Disorders, 2001Co-Authors: Richard J Piercy, Kenneth W. Hinchcliff, Gregory A Reinhart, Stuart L Nelson, Karin E Schmidt, Robert A. Disilvestro, Paul S. Morley, Morrie A CraigAbstract:Exertional rhabdomyolysis (ER) is common in Sled Dogs, animals with high energy expenditures that consume high fat (60% of ingested calories) diets. Associations between pre-race plasma [vitamin E] and total antioxidant status (TAS) and risk of developing ER were examined in Dogs competing in the 1998 Iditarod race. Pre-race blood samples were collected from 750 Dogs and a second sample was collected from 158 Dogs withdrawn from the race at various times. Plasma creatine kinase activity was used to identify withdrawn Dogs with ER. There was no association between pre-race plasma [vitamin E] and risk of development of ER. Dogs that developed ER started the race with higher TAS, but when withdrawn, had lower TAS than unaffected Dogs and had similar pre-race [vitamin E] but higher [vitamin E] at time of withdrawal. Hence, the risk of ER in Sled Dogs is not affected by plasma [vitamin E] before the race.
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Effect of distance traveled and speed of racing on body weight and serum enzyme activity of Sled Dogs competing in a long-distance race.
Javma-journal of The American Veterinary Medical Association, 1998Co-Authors: Kenneth W. Hinchcliff, Shaw Lc, Vukich Ns, Karin E SchmidtAbstract:OBJECTIVE: To determine the relationship of serum biochemical values and change in body weight with finishing status (retired from or finished the race), finishing order of a team, and distance traveled for Dogs participating in a long-distance Sled Dog race. ANIMALS: 262 of 848 Dogs that participated in the 1995 Iditarod Trail Sled Dog race. DESIGN: Prospective study. PROCEDURE: Body weight was recorded for 261 Dogs before the race and again when these Dogs retired from or completed the race. Using a nonrandom convenience sample of participating Dogs, blood samples were obtained from 151 Dogs that retired from the race and 111 Dogs that completed the race. RESULTS: Serum biochemical indices of skeletal muscle damage were significantly higher in Dogs retiring during the first 500 miles of the race than in Dogs retiring in the last 638 miles or finishing the race. Serum sodium concentration was less than the reference range in a significantly greater proportion of Dogs that retired from the race than of Dogs that completed the race. There was little relationship between finishing order and serum biochemical values. Dogs completing the race lost a mean of 8.9% of body weight, and amount of weight lost was not related to finishing order. CLINICAL IMPLICATIONS: Results indicated that exertional rhabdomyolysis develops more often in Dogs that retire during the initial 500 miles of a long-distance race, compared with Dogs that complete the race. There is no detectable relationship between the speed with which the race is run (finishing order) and body weight loss or serum biochemical values.
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ELECTROCARDIOGRAPHIC CHARACTERISTICS OF ENDURANCE-TRAINED ALASKAN Sled DogS
Javma-journal of The American Veterinary Medical Association, 1997Co-Authors: Kenneth W. Hinchcliff, Karin E Schmidt, P D Constable, James W. Farris, Robert L. HamlinAbstract:OBJECTIVE: To determine electrocardiographic characteristics of endurance-trained Alaskan Sled Dogs. DESIGN: Case series. ANIMALS: 319 Alaskan Sled Dogs entered to compete in the 1994 Iditarod Trail Sled Dog Race. PROCEDURE: ECG were recorded while Dogs were standing and were analyzed digitally. RESULTS: Amplitudes of P waves (median, 0.40 mV; fifth to 95th percentile range, 0.11 to 0.61 mV) and R waves in lead II (median, 3.02 mV; fifth to 95th percentile range, 1.49 to 4.40 mV) were high; durations of P waves in lead II (median, 61 milliseconds; fifth to 95th percentile range, 36 to 96 milliseconds), QRS complexes (median, 64 milliseconds; fifth to 95th percentile range, 52 to 80 milliseconds), and QT intervals (median, 236 milliseconds; fifth to 95th percentile range, 208 to 277 milliseconds) were prolonged. Median value for mean axis of ventricular depolarization was 57 degrees (fifth to 95th percentile range, 19 to 90 degrees). Atrial and ventricular premature depolarizations were observed in 3 (0.9%) and 4 (1.3%) of 319 Dogs, respectively, and paroxysmal ventricular tachycardia was detected in 1 (0.3%). CLINICAL IMPLICATIONS: Results suggest that electrocardiographic characteristics of endurance-trained Alaskan Sled Dogs differ from those reported for nonSled Dogs, probably as a result of effects of endurance training on heart size. Some of these characteristics could be mistaken as evidence of pathologic cardiac hypertrophy.
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Factors associated with finishing status for Dogs competing in a long-distance Sled race.
Javma-journal of The American Veterinary Medical Association, 1996Co-Authors: P D Constable, Kenneth W. Hinchcliff, James W. Farris, Karin E SchmidtAbstract:OBJECTIVE: To determine whether selected factors were associated with finishing status in a long-distance Sled Dog race. DESIGN: Prospective, observational study. ANIMALS: 248 Dogs participating in the 1994 Iditarod trail Sled race that were members of 13 teams that finished the race. Dogs were not selected randomly, but were members of teams that were easily accessible for examination before the race. The proportion of teams that were examined that finished the race (14/17) was similar to the proportion of teams that were not examined that finished the race (36/41). PROCEDURE: Age, sex, body conformation (weight, length, and thoracic width and circumference), cardiac variables (heart rate, natural logarithm of heart period variance, PR interval, QRS duration, QT index, R wave amplitude in leads II and V3, mean electrical axis, presence of cardiac arrhythmias suggestive of myocardial disease), and athletic ranking as assessed by the musher were compared between Dogs that finished the race (n = 128) and Dogs that did not finish (n = 120). RESULTS: The only factor found to differ significantly (P < 0.05) between finishers and nonfinishers was athletic ranking as assessed by the musher. Athletic rank and QRS duration or QRS duration normalized for body weight were identified by means of logistic regression as variables associated (P < 0.15) with finishing status. There was a significant (P < 0.0001), but weak (R2 = 0.18), linear relationship between race time and mean QRS duration for each team. CLINICAL IMPLICATIONS: Athletic ranking as assessed by the musher was the most important of the studied variables in determining finishing status, whereas age, sex, body conformation, and body weight were unimportant. Duration of the QRS was of minor importance in determining finishing status.