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P Lord - One of the best experts on this subject based on the ideXlab platform.

  • Culling Rate of Icelandic Horses due to Bone Spavin
    2013
    Co-Authors: Sigridur Bjornsdottir, Th Árnason, P Lord
    Abstract:

    the culling rate of Icelandic horses due to the presence of radiographic and clinical signs of Bone Spavin. A follow-up study of 508 horses from a survey five years earlier was performed. In the original survey 46 % of the horses had radiographic signs of Bone Spavin (RS) and / or lameness after flexion test of the tarsus. The horse owners were interviewed by telephone. The owners were asked if the horses were still used for riding and if not, they were regarded as culled. The owners were then asked when and why the horses were culled. During the 5 years, 98 horses had been culled, 151 had been withdrawn (sold or selected for breeding) and 259 were still used for riding. Hind limb lameness (HLL) was the most common reason for culling (n=42). The rate of culling was low up to the age of 11 years, when it rose to 0.05 for horses with RS. The risk ratio for culling was twice as high for horses with RS compared with horses without RS and 5.5 times higher for culling because of HLL. The risk of culling (prognostic value) was highest for the combination of RS with lameness after flexion test, next highest for RS and lowest for lameness after flexion test as the only finding. It was concluded that Bone Spavin affects the duration of use of Icelandic horses and is the most common cause of culling due to disease of riding horses in the age range of 7-17 years. Icelandic horses; Bone Spavin osteoarthroses; survival analysis; questionnaire

  • Culling Rate of Icelandic Horses due to Bone Spavin
    Acta Veterinaria Scandinavica, 2003
    Co-Authors: Sigridur Bjornsdottir, Th Árnason, P Lord
    Abstract:

    A survival analysis was used to compare the culling rate of Icelandic horses due to the presence of radiographic and clinical signs of Bone Spavin. A follow-up study of 508 horses from a survey five years earlier was performed. In the original survey 46% of the horses had radiographic signs of Bone Spavin (RS) and/or lameness after flexion test of the tarsus. The horse owners were interviewed by telephone. The owners were asked if the horses were still used for riding and if not, they were regarded as culled. The owners were then asked when and why the horses were culled. During the 5 years, 98 horses had been culled, 151 had been withdrawn (sold or selected for breeding) and 259 were still used for riding. Hind limb lameness (HLL) was the most common reason for culling (n = 42). The rate of culling was low up to the age of 11 years, when it rose to 0.05 for horses with RS. The risk ratio for culling was twice as high for horses with RS compared with horses without RS and 5.5 times higher for culling because of HLL. The risk of culling (prognostic value) was highest for the combination of RS with lameness after flexion test, next highest for RS and lowest for lameness after flexion test as the only finding. It was concluded that Bone Spavin affects the duration of use of Icelandic horses and is the most common cause of culling due to disease of riding horses in the age range of 7–17 years.

Sigridur Bjornsdottir - One of the best experts on this subject based on the ideXlab platform.

  • Culling Rate of Icelandic Horses due to Bone Spavin
    2013
    Co-Authors: Sigridur Bjornsdottir, Th Árnason, P Lord
    Abstract:

    the culling rate of Icelandic horses due to the presence of radiographic and clinical signs of Bone Spavin. A follow-up study of 508 horses from a survey five years earlier was performed. In the original survey 46 % of the horses had radiographic signs of Bone Spavin (RS) and / or lameness after flexion test of the tarsus. The horse owners were interviewed by telephone. The owners were asked if the horses were still used for riding and if not, they were regarded as culled. The owners were then asked when and why the horses were culled. During the 5 years, 98 horses had been culled, 151 had been withdrawn (sold or selected for breeding) and 259 were still used for riding. Hind limb lameness (HLL) was the most common reason for culling (n=42). The rate of culling was low up to the age of 11 years, when it rose to 0.05 for horses with RS. The risk ratio for culling was twice as high for horses with RS compared with horses without RS and 5.5 times higher for culling because of HLL. The risk of culling (prognostic value) was highest for the combination of RS with lameness after flexion test, next highest for RS and lowest for lameness after flexion test as the only finding. It was concluded that Bone Spavin affects the duration of use of Icelandic horses and is the most common cause of culling due to disease of riding horses in the age range of 7-17 years. Icelandic horses; Bone Spavin osteoarthroses; survival analysis; questionnaire

  • Culling Rate of Icelandic Horses due to Bone Spavin
    Acta Veterinaria Scandinavica, 2003
    Co-Authors: Sigridur Bjornsdottir, Th Árnason, P Lord
    Abstract:

    A survival analysis was used to compare the culling rate of Icelandic horses due to the presence of radiographic and clinical signs of Bone Spavin. A follow-up study of 508 horses from a survey five years earlier was performed. In the original survey 46% of the horses had radiographic signs of Bone Spavin (RS) and/or lameness after flexion test of the tarsus. The horse owners were interviewed by telephone. The owners were asked if the horses were still used for riding and if not, they were regarded as culled. The owners were then asked when and why the horses were culled. During the 5 years, 98 horses had been culled, 151 had been withdrawn (sold or selected for breeding) and 259 were still used for riding. Hind limb lameness (HLL) was the most common reason for culling (n = 42). The rate of culling was low up to the age of 11 years, when it rose to 0.05 for horses with RS. The risk ratio for culling was twice as high for horses with RS compared with horses without RS and 5.5 times higher for culling because of HLL. The risk of culling (prognostic value) was highest for the combination of RS with lameness after flexion test, next highest for RS and lowest for lameness after flexion test as the only finding. It was concluded that Bone Spavin affects the duration of use of Icelandic horses and is the most common cause of culling due to disease of riding horses in the age range of 7–17 years.

  • Heritability of age-at-onset of Bone Spavin in Icelandic horses estimated by survival analysis
    Livestock Production Science, 2002
    Co-Authors: Th Árnason, Sigridur Bjornsdottir
    Abstract:

    Abstract Age-at-onset of Bone Spavin (BS) in horses was defined as a double-censored survival variable. A small material of binary responses to a radiographic examination of the distal tarsus in 439 Icelandic horses sired by 17 stallions was analysed. In order to test different models larger simulated data were generated according to an exponential proportional hazard model and subject to censoring. The resulting survivor functions were similar. The bias in survivor functions caused by double censoring in the material was reduced by use of the self-consistency (S-C) algorithm. Using a binary threshold model and the Weibull regression model, an analysis of age-at-onset of Spavin resulted in severe underestimation of sire variance components in the simulated data. Survival analysis with Prentice and Gloeckler’s (1978) model led to less biased estimates. Application of this method on the real data resulted in an effective heritability estimate of h 2 =0.33, which can be compared with an estimate of h 2 =0.1 based on an analysis of radiographic signs (RS) using the binary threshold model. These results indicate that the age-at-onset of RS, which reflect the predisposition of BS, is a trait with medium-high heritability.

R K W Smith - One of the best experts on this subject based on the ideXlab platform.

  • tiludronate infusion in the treatment of Bone Spavin a double blind placebo controlled trial
    Equine Veterinary Journal, 2010
    Co-Authors: M R Gough, D Thibaud, R K W Smith
    Abstract:

    Summary Reasons for performing study: Tiludronate regulates Bone remodelling through a decrease of the resorptive process and should therefore ameliorate the remodelling processes active in osteoarthritis of the distal tarsal joints (‘Bone Spavin’) and alleviate pain associated with abnormal Bone lysis. Objective: To confirm the efficacy of tiludronate, administered as a single infusion at a dose of 1 mg/kg bwt, in the treatment of Bone Spavin in the horse. Methods: A double blind placebo controlled trial on 108 clinical cases of Bone Spavin was undertaken. The lameness score of the lamest limb was assessed following distal tarsal analgesia of the contralateral limb and followed-up using the same procedure throughout the study. Bone Spavin in the lamest limb was confirmed by distal tarsal analgesia and radiography. Horses were treated at Day 0 and reassessed 60 days later after controlled exercise. A second nonblinded treatment was given to unresponsive horses and all horses were re-examined at Day 120. Exercise levels were recorded at each examination. Results: Eighty-seven horses completed the trial as per the protocol. The tiludronate horses were significantly less lame than the placebo horses (P = 0.0318). Horses treated at Day 60 with tiludronate showed further improvement in lameness at Day 120 (P = 0.0096 and P = 0.0034 for horses treated with tiludronate and placebo at Day 0, respectively). The only significant difference in radiographic findings between tiludronate and placebo was for presence of periarticular osteophytes (P = 0.006). Conclusions: Tiludronate treatment is proven to be effective in Bone Spavin in horses in association with a controlled exercise programme. Clinical relevance: Tiludronate in combination with controlled exercise offers an alternate medical treatment for Bone Spavin.

Th Árnason - One of the best experts on this subject based on the ideXlab platform.

  • Culling Rate of Icelandic Horses due to Bone Spavin
    2013
    Co-Authors: Sigridur Bjornsdottir, Th Árnason, P Lord
    Abstract:

    the culling rate of Icelandic horses due to the presence of radiographic and clinical signs of Bone Spavin. A follow-up study of 508 horses from a survey five years earlier was performed. In the original survey 46 % of the horses had radiographic signs of Bone Spavin (RS) and / or lameness after flexion test of the tarsus. The horse owners were interviewed by telephone. The owners were asked if the horses were still used for riding and if not, they were regarded as culled. The owners were then asked when and why the horses were culled. During the 5 years, 98 horses had been culled, 151 had been withdrawn (sold or selected for breeding) and 259 were still used for riding. Hind limb lameness (HLL) was the most common reason for culling (n=42). The rate of culling was low up to the age of 11 years, when it rose to 0.05 for horses with RS. The risk ratio for culling was twice as high for horses with RS compared with horses without RS and 5.5 times higher for culling because of HLL. The risk of culling (prognostic value) was highest for the combination of RS with lameness after flexion test, next highest for RS and lowest for lameness after flexion test as the only finding. It was concluded that Bone Spavin affects the duration of use of Icelandic horses and is the most common cause of culling due to disease of riding horses in the age range of 7-17 years. Icelandic horses; Bone Spavin osteoarthroses; survival analysis; questionnaire

  • Culling Rate of Icelandic Horses due to Bone Spavin
    Acta Veterinaria Scandinavica, 2003
    Co-Authors: Sigridur Bjornsdottir, Th Árnason, P Lord
    Abstract:

    A survival analysis was used to compare the culling rate of Icelandic horses due to the presence of radiographic and clinical signs of Bone Spavin. A follow-up study of 508 horses from a survey five years earlier was performed. In the original survey 46% of the horses had radiographic signs of Bone Spavin (RS) and/or lameness after flexion test of the tarsus. The horse owners were interviewed by telephone. The owners were asked if the horses were still used for riding and if not, they were regarded as culled. The owners were then asked when and why the horses were culled. During the 5 years, 98 horses had been culled, 151 had been withdrawn (sold or selected for breeding) and 259 were still used for riding. Hind limb lameness (HLL) was the most common reason for culling (n = 42). The rate of culling was low up to the age of 11 years, when it rose to 0.05 for horses with RS. The risk ratio for culling was twice as high for horses with RS compared with horses without RS and 5.5 times higher for culling because of HLL. The risk of culling (prognostic value) was highest for the combination of RS with lameness after flexion test, next highest for RS and lowest for lameness after flexion test as the only finding. It was concluded that Bone Spavin affects the duration of use of Icelandic horses and is the most common cause of culling due to disease of riding horses in the age range of 7–17 years.

  • Heritability of age-at-onset of Bone Spavin in Icelandic horses estimated by survival analysis
    Livestock Production Science, 2002
    Co-Authors: Th Árnason, Sigridur Bjornsdottir
    Abstract:

    Abstract Age-at-onset of Bone Spavin (BS) in horses was defined as a double-censored survival variable. A small material of binary responses to a radiographic examination of the distal tarsus in 439 Icelandic horses sired by 17 stallions was analysed. In order to test different models larger simulated data were generated according to an exponential proportional hazard model and subject to censoring. The resulting survivor functions were similar. The bias in survivor functions caused by double censoring in the material was reduced by use of the self-consistency (S-C) algorithm. Using a binary threshold model and the Weibull regression model, an analysis of age-at-onset of Spavin resulted in severe underestimation of sire variance components in the simulated data. Survival analysis with Prentice and Gloeckler’s (1978) model led to less biased estimates. Application of this method on the real data resulted in an effective heritability estimate of h 2 =0.33, which can be compared with an estimate of h 2 =0.1 based on an analysis of radiographic signs (RS) using the binary threshold model. These results indicate that the age-at-onset of RS, which reflect the predisposition of BS, is a trait with medium-high heritability.

J. Carlsten - One of the best experts on this subject based on the ideXlab platform.

  • Prevalence and Risk Factors of Bone Spavin in Icelandic Horses in Sweden: A Radiographic Field Study
    Acta Veterinaria Scandinavica, 1998
    Co-Authors: Per Eksell, M. Axelsson, H. Broström, B. Ronéus, J. Häggström, J. Carlsten
    Abstract:

    The present field study was performed to estimate the prevalence of radiographic signs of Bone Spavin (RSBS) and to evaluate some possible risk factors for RSBS in the Icelandic horse in Sweden. The survey in-cluded horses from 11 farms involving 379 horses, comprising 238 geldings, 125 mares and 16 stallions. Age ranged from 0 to 19 years with a mean age of 8.1 years. Horses were radiographed with a dorsolateral-plantaromedial-oblique projection of both tarsi. Information about age, gender, origin, working intensity, number of gaits and age when saddle broken were obtained by interviewing the owners. Features of each horse’s con-formation were obtained by measurement or inspection. Radiographic signs of Bone Spavin were found in 23% (n = 88) of the horses. Horses younger than 5 years did not show any RSBS and the prevalence increased from zero to 33% between 4 and 8 years of age. Using a multivariate logistic regression model in-creasing age and sickle hock conformation were found to be significantly associated with increased risk of RSBS. Age when saddle broken in combination with height at the withers also influenced the multivariate logistic regression model significantly.

  • Relationship between hind limb lameness and radiographic signs of Bone Spavin in Icelandic horses in Sweden.
    Acta Veterinaria Scandinavica, 1998
    Co-Authors: M. Axelsson, Per Eksell, Ronéus B, Broström H, Häggström J, J. Carlsten
    Abstract:

    : A field study was designed to estimate the prevalence of hind limb lameness in a population of Icelandic horses in Sweden. All available Icelandic horses at 11 different farms within 150 km from Uppsala were examined once during a study period of 13 months. The relationship between hind limb lameness and radiographic signs of Bone Spavin (RSBS) was investigated. The rate of agreement between the outcome after palpation, motion evaluation and flexion test and radiographic examination was established. A total of 379 horses including 238 geldings, 125 mares and 16 stallions, with mean age 8.1 years (range 1-19 years) were examined by palpation of the medial aspect of the tarsal joints, motion evaluation and flexion test of the hind limbs. One dorsolateral-plantaromedial oblique radiographic view was recorded from each tarsus. Palpable abnormalities were found in 118 horses (31%). Forty-three horses (12%) were lame at presentation, 94 horses (25%) were positive on flexion test and 88 horses (23%) had RSBS. There was a significant relationship between palpable abnormalities, lameness, positive flexion test and RSBS. The proportion of joints with RSBS increased with increasing severity of physical findings. The proportion of lame limbs increased with increasing radiographic changes. The presence of palpable findings or positive flexion test was not influenced by the grading of radiographic changes. Using palpation, motion evaluation, and flexion test 75% of the horses with RSBS were identified. The rate of agreement between the clinical examination and the radiographic examination was 73%.