The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Fred M. Hopkins - One of the best experts on this subject based on the ideXlab platform.
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Breeding Soundness evaluations of 3648 yearling beef bulls using the 1993 Society for Theriogenology guidelines
Theriogenology, 2002Co-Authors: S.p Kennedy, J.c. Spitzer, Fred M. Hopkins, H.l. Higdon, William C. BridgesAbstract:Abstract Our objective was to perform a retrospective analysis of Breeding Soundness evaluations (BSEs) as classified by the 1993 Society for Theriogenology (SFT) guidelines [Chenoweth et al., Guidelines for using the bull Breeding Soundness evaluation form, in: Theriogenology Handbook, 1993, pp. B-10]. Data included BSE information obtained from five performance-testing stations in South Carolina (SC1, SC2, SC3) and Tennessee (TN1, TN2) from 1986 through 1999 on 3648 Angus, Brangus, Charolais, Chianina, Gelbvieh, Limousin, Polled Hereford, Santa Gertrudis, Simbrah, and Simmental bulls. Analyses were simplified by classifying all bulls as either satisfactory or unsatisfactory potential breeders. Of the 3648 bulls evaluated, 76.2% were classified as satisfactory potential breeders. Of all bulls evaluated, 4.0% were unsatisfactory due to inadequate spermatozoal motility, 7.0% due to inadequate spermatozoal morphology and 2.6% due to a combination of inadequate motility and morphology. Unsatisfactory classifications due to non-spermatozoal parameters out of all bulls were 10.2%, with 7.1% for inadequate scrotal circumference and 3.1% for physical abnormalities. For satisfactory and unsatisfactory bulls, respectively, means and standard deviations were 35.8±2.7 and 33.0±4.1 cm (P
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outcomes of Breeding Soundness evaluation of 2898 yearling bulls subjected to different classification systems
Theriogenology, 2000Co-Authors: H.l. Higdon, J.c. Spitzer, Fred M. Hopkins, William C. BridgesAbstract:Abstract This study is a retrospective analysis comparing data on yearling bull Breeding Soundness evaluation (BSE) subjected to 3 different classification systems: the Society for Theriogenology (SFT) 1983 and 1993 systems, and the Western Canadian Association of Bovine Practitioners (WC) 1993 system. Data were collected at 5 performance bull-test stations located in South Carolina and Tennessee from 1986 through 1996. Yearling bulls (n = 2898) that were 10 to 20 mo of age were used in the analysis. To simplify analysis, bulls were determined to be either satisfactory or unsatisfactory potential breeders (including those classified as questionable, deferred or unsatisfactory). Data were analyzed 1) within location where a location was treated as an individual experiment, 2) with breeds and locations collapsed, and 3) within age-group where each age-group was treated as an individual experiment. An ANOVA was performed using GLM procedures of SAS, and this model was used to generate least square means for the proportion of bulls classified as satisfactory and the 5 possible unsatisfactory outcomes due to inadequacies in scrotal circumference, spermatozoal morphology, spermatozoal motility, a combination of inadequate spermatozoal morphology and motility, or physical abnormalities. Inadequate scrotal circumference or physical abnormality did not affect differences for BSE outcomes among systems. Using the SFT93 system, bulls failed at a higher rate due to inadequate spermatozoal morphology (P
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the new society for theriogenology Breeding Soundness evaluation system
Veterinary Clinics of North America-food Animal Practice, 1997Co-Authors: Fred M. Hopkins, J.c. SpitzerAbstract:In 1993, The Society for Theriogenology published revised standards for Breeding Soundness evaluation of bulls. These revised standards replaced the old semen score format with minimum acceptable scores for scrotal circumference (varies with age), motility (30% or fair), and morphology (70%).
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Breeding Soundness Evaluation of Yearling Bulls
Veterinary Clinics of North America: Food Animal Practice, 1997Co-Authors: J.c. Spitzer, Fred M. HopkinsAbstract:Breeding Soundness Evaluations (BSEs) are a useful tool to improve reproductive performance and profitability in beef herds. Veterinarians providing this service must be thorough in their evaluation, especially in yearling bulls. The 1993 Society for Theriogenology guidelines for BSE provide appropriate standards for classifying yearling bulls; veterinarians are advised to adhere to these standards as minimums for classification of the satisfactory potential breeder.
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new guidelines for the evaluation of bulls for Breeding Soundness
American Association of Bovine Practitioners Proceedings of the Annual Conference, 1993Co-Authors: P J Chenoweth, J.c. Spitzer, Fred M. Hopkins, Rolf E LarsonAbstract:New guidelines for bull Breeding Soundness examinations (BSE) were recently adopted by the American Society for Theriogenology. Major new features included the abandonment of numerical scores in favor of threshold values which must be achieved for scrotal circumference (minimum threshold of 30 cm at 15 months of age), spermatozoal motility (minimum threshold of 30% individual motility) and spermatozoal morphology (minimum threshold of 70% normal sperm). The latter requirement is seen to reduce the emphasis on classification systems (e.g. "primary'' and "secondary'' abnormalities) for sperm morphology assessment. Bulls are classified as being either "satisfactory'' or "unsatisfactory" or they are placed in a "classification deferred" category. Forms and explanatory notes are available to members of the society for Theriogenology from the Society office.
J.c. Spitzer - One of the best experts on this subject based on the ideXlab platform.
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Breeding Soundness evaluations of 3648 yearling beef bulls using the 1993 Society for Theriogenology guidelines
Theriogenology, 2002Co-Authors: S.p Kennedy, J.c. Spitzer, Fred M. Hopkins, H.l. Higdon, William C. BridgesAbstract:Abstract Our objective was to perform a retrospective analysis of Breeding Soundness evaluations (BSEs) as classified by the 1993 Society for Theriogenology (SFT) guidelines [Chenoweth et al., Guidelines for using the bull Breeding Soundness evaluation form, in: Theriogenology Handbook, 1993, pp. B-10]. Data included BSE information obtained from five performance-testing stations in South Carolina (SC1, SC2, SC3) and Tennessee (TN1, TN2) from 1986 through 1999 on 3648 Angus, Brangus, Charolais, Chianina, Gelbvieh, Limousin, Polled Hereford, Santa Gertrudis, Simbrah, and Simmental bulls. Analyses were simplified by classifying all bulls as either satisfactory or unsatisfactory potential breeders. Of the 3648 bulls evaluated, 76.2% were classified as satisfactory potential breeders. Of all bulls evaluated, 4.0% were unsatisfactory due to inadequate spermatozoal motility, 7.0% due to inadequate spermatozoal morphology and 2.6% due to a combination of inadequate motility and morphology. Unsatisfactory classifications due to non-spermatozoal parameters out of all bulls were 10.2%, with 7.1% for inadequate scrotal circumference and 3.1% for physical abnormalities. For satisfactory and unsatisfactory bulls, respectively, means and standard deviations were 35.8±2.7 and 33.0±4.1 cm (P
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outcomes of Breeding Soundness evaluation of 2898 yearling bulls subjected to different classification systems
Theriogenology, 2000Co-Authors: H.l. Higdon, J.c. Spitzer, Fred M. Hopkins, William C. BridgesAbstract:Abstract This study is a retrospective analysis comparing data on yearling bull Breeding Soundness evaluation (BSE) subjected to 3 different classification systems: the Society for Theriogenology (SFT) 1983 and 1993 systems, and the Western Canadian Association of Bovine Practitioners (WC) 1993 system. Data were collected at 5 performance bull-test stations located in South Carolina and Tennessee from 1986 through 1996. Yearling bulls (n = 2898) that were 10 to 20 mo of age were used in the analysis. To simplify analysis, bulls were determined to be either satisfactory or unsatisfactory potential breeders (including those classified as questionable, deferred or unsatisfactory). Data were analyzed 1) within location where a location was treated as an individual experiment, 2) with breeds and locations collapsed, and 3) within age-group where each age-group was treated as an individual experiment. An ANOVA was performed using GLM procedures of SAS, and this model was used to generate least square means for the proportion of bulls classified as satisfactory and the 5 possible unsatisfactory outcomes due to inadequacies in scrotal circumference, spermatozoal morphology, spermatozoal motility, a combination of inadequate spermatozoal morphology and motility, or physical abnormalities. Inadequate scrotal circumference or physical abnormality did not affect differences for BSE outcomes among systems. Using the SFT93 system, bulls failed at a higher rate due to inadequate spermatozoal morphology (P
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the new society for theriogenology Breeding Soundness evaluation system
Veterinary Clinics of North America-food Animal Practice, 1997Co-Authors: Fred M. Hopkins, J.c. SpitzerAbstract:In 1993, The Society for Theriogenology published revised standards for Breeding Soundness evaluation of bulls. These revised standards replaced the old semen score format with minimum acceptable scores for scrotal circumference (varies with age), motility (30% or fair), and morphology (70%).
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Breeding Soundness Evaluation of Yearling Bulls
Veterinary Clinics of North America: Food Animal Practice, 1997Co-Authors: J.c. Spitzer, Fred M. HopkinsAbstract:Breeding Soundness Evaluations (BSEs) are a useful tool to improve reproductive performance and profitability in beef herds. Veterinarians providing this service must be thorough in their evaluation, especially in yearling bulls. The 1993 Society for Theriogenology guidelines for BSE provide appropriate standards for classifying yearling bulls; veterinarians are advised to adhere to these standards as minimums for classification of the satisfactory potential breeder.
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new guidelines for the evaluation of bulls for Breeding Soundness
American Association of Bovine Practitioners Proceedings of the Annual Conference, 1993Co-Authors: P J Chenoweth, J.c. Spitzer, Fred M. Hopkins, Rolf E LarsonAbstract:New guidelines for bull Breeding Soundness examinations (BSE) were recently adopted by the American Society for Theriogenology. Major new features included the abandonment of numerical scores in favor of threshold values which must be achieved for scrotal circumference (minimum threshold of 30 cm at 15 months of age), spermatozoal motility (minimum threshold of 30% individual motility) and spermatozoal morphology (minimum threshold of 70% normal sperm). The latter requirement is seen to reduce the emphasis on classification systems (e.g. "primary'' and "secondary'' abnormalities) for sperm morphology assessment. Bulls are classified as being either "satisfactory'' or "unsatisfactory" or they are placed in a "classification deferred" category. Forms and explanatory notes are available to members of the society for Theriogenology from the Society office.
Mf Pyman - One of the best experts on this subject based on the ideXlab platform.
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an assessment of dairy herd bulls in southern australia 2 analysis of bull and herd level risk factors and their associations with pre and postmating Breeding Soundness results
Journal of Dairy Science, 2016Co-Authors: A.s. Hancock, D S Beggs, P.j. Younis, Peter D. Mansell, Mark Stevenson, Mf PymanAbstract:Abstract In pasture-based, seasonally calving dairy herds of southern Australia, the mating period usually consists of an initial artificial insemination period followed by a period of natural service using herd bulls. The primary objective of this study was to identify associations between individual bull- and herd-level management factors and bull fertility as measured by a pre- and postmating bull Breeding Soundness evaluation (BBSE). Multivariable mixed effects logistic regression models were used to identify factors associated with bulls being classified as high risk of reduced fertility at the premating and postmating BBSE. Bulls older than 4 yr of age at the premating BBSE were more likely to be classified high risk compared with bulls less than 4 yr of age. Bulls that were in herds in which concentrates were fed before mating were more likely to be classified as high risk at the postmating BBSE compared with bulls that were in herds where concentrates were not fed. Univariable analyses also identified areas in need of further research, including breed differences between dairy bulls, leg conformation and joint abnormalities, preventative hoof blocking for bulls, and mating ratios.
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An assessment of dairy herd bulls in southern Australia: 1. Management practices and bull Breeding Soundness evaluations.
Journal of Dairy Science, 2016Co-Authors: A.s. Hancock, D S Beggs, P.j. Younis, Peter D. Mansell, Mark Stevenson, Mf PymanAbstract:Abstract In the pasture-based, seasonally calving dairy herds of southern Australia, the mating period usually consists of an initial artificial insemination period followed by a period of natural service using herd bulls. Bull Breeding Soundness evaluations (BBSE) were performed on 256 bulls from 32 dairy herds in southwest Victoria, using guidelines produced by the Australian Cattle Veterinarians, before and immediately after a single natural mating period. At the same time, herd managers were questioned regarding the management of the bulls. The objectives of this study were to describe the management practices of dairy herd bulls; to describe the causes of increased risk of reduced fertility in dairy herd bulls, as measured by a standard BBSE; and to describe the reasons for bull removal by herd managers during mating. At the premating BBSE, 19.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities and reduced semen quality. At the postmating BBSE, 36.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities, primarily lameness. Of the bulls used, 15.9% were removed from normal mating use by the herd manager, predominantly due to lameness and injuries. A premating BBSE is recommended in dairy herd bulls to identify bulls at risk of reduced fertility. Lameness is the most common problem in dairy herd bulls during the natural mating period, and risk factors associated with lameness in these bulls should be identified to better manage herd bulls.
Robert L Larson - One of the best experts on this subject based on the ideXlab platform.
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scrotal circumference at weaning in beef bulls and subsequent ability to pass a Breeding Soundness examination as a yearling
The Bovine practitioner, 2020Co-Authors: Tara H Fountain, Robert L Larson, Brad J WhiteAbstract:Identifying bulls at weaning with higher likelihood ofpassing a Breeding Soundness examination as yearlings mayimprove management options to optimize production efficiency.The objective of this study was to evaluate the effect of weaning scrotal circumference and other factors collected at the time of weaning on the likelihood of passing a Breeding Soundness examination as a yearling. Data, at both weaning and time of Breeding Soundness examination, were collected from 1 operation (n = 466 bulls). A logistic regression model was used to evaluate the potential associations of relevant factors (actual weaning scrotal circumference, adjusted weaning scrotal circumference, weight per day of age at weaning, scrotal circumference per day of age at weaning, weaning weight, and breed) on the probability of passing a Breeding Soundness examination as a yearling. Overall, 92.3% of bulls passed the yearling Breeding Soundness examination on first evaluation. Weaning scrotal circumference was the only factor of those evaluated associated (P < 0.01) with the probability of passing the Breeding Soundness examination. No significant differences were found between the categories of weaning scrotal circumference. In the future, more research needs to evaluate predictive model development for weaning scrotal circumference and ability to pass Breeding Soundness examination.
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factors associated with yearling bulls passing subsequent Breeding Soundness evaluations after failing an initial evaluation
Javma-journal of The American Veterinary Medical Association, 2018Co-Authors: Jessica D Monday, Robert L Larson, Brad J White, Miles E Theurer, Sharon TuckerAbstract:OBJECTIVE To determine the proportion of yearling beef bulls classified as satisfactory potential breeders when reevaluated after failing an initial Breeding Soundness evaluation (BSE) and identify...
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Yearling Bull Breeding Soundness Examination: Special Considerations.
Veterinary Clinics of North America: Food Animal Practice, 2016Co-Authors: Nora Schrag, Robert L LarsonAbstract:Accurate assessment of yearling bulls is important for the bottom line of all interested parties: the buyer, the seller, and the veterinarian performing the BSE. Special considerations and current research are highlighted and their application to the evaluation of yearling bulls is discussed.
A.s. Hancock - One of the best experts on this subject based on the ideXlab platform.
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an assessment of dairy herd bulls in southern australia 2 analysis of bull and herd level risk factors and their associations with pre and postmating Breeding Soundness results
Journal of Dairy Science, 2016Co-Authors: A.s. Hancock, D S Beggs, P.j. Younis, Peter D. Mansell, Mark Stevenson, Mf PymanAbstract:Abstract In pasture-based, seasonally calving dairy herds of southern Australia, the mating period usually consists of an initial artificial insemination period followed by a period of natural service using herd bulls. The primary objective of this study was to identify associations between individual bull- and herd-level management factors and bull fertility as measured by a pre- and postmating bull Breeding Soundness evaluation (BBSE). Multivariable mixed effects logistic regression models were used to identify factors associated with bulls being classified as high risk of reduced fertility at the premating and postmating BBSE. Bulls older than 4 yr of age at the premating BBSE were more likely to be classified high risk compared with bulls less than 4 yr of age. Bulls that were in herds in which concentrates were fed before mating were more likely to be classified as high risk at the postmating BBSE compared with bulls that were in herds where concentrates were not fed. Univariable analyses also identified areas in need of further research, including breed differences between dairy bulls, leg conformation and joint abnormalities, preventative hoof blocking for bulls, and mating ratios.
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An assessment of dairy herd bulls in southern Australia: 1. Management practices and bull Breeding Soundness evaluations.
Journal of Dairy Science, 2016Co-Authors: A.s. Hancock, D S Beggs, P.j. Younis, Peter D. Mansell, Mark Stevenson, Mf PymanAbstract:Abstract In the pasture-based, seasonally calving dairy herds of southern Australia, the mating period usually consists of an initial artificial insemination period followed by a period of natural service using herd bulls. Bull Breeding Soundness evaluations (BBSE) were performed on 256 bulls from 32 dairy herds in southwest Victoria, using guidelines produced by the Australian Cattle Veterinarians, before and immediately after a single natural mating period. At the same time, herd managers were questioned regarding the management of the bulls. The objectives of this study were to describe the management practices of dairy herd bulls; to describe the causes of increased risk of reduced fertility in dairy herd bulls, as measured by a standard BBSE; and to describe the reasons for bull removal by herd managers during mating. At the premating BBSE, 19.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities and reduced semen quality. At the postmating BBSE, 36.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities, primarily lameness. Of the bulls used, 15.9% were removed from normal mating use by the herd manager, predominantly due to lameness and injuries. A premating BBSE is recommended in dairy herd bulls to identify bulls at risk of reduced fertility. Lameness is the most common problem in dairy herd bulls during the natural mating period, and risk factors associated with lameness in these bulls should be identified to better manage herd bulls.