• 1. Barth A. Pubertal development of beef bulls, in Proceedings. 22nd Annual Texas A&M Food Anim Conf Bull Quality Assurance 2013;4760.

    • Search Google Scholar
    • Export Citation
  • 2. Barth A, Brito LFC. Pubertal development of Bos taurus beef bulls. Large Anim Vet Round 2004;34:5454.

  • 3. Brito LF, Barth AD, Wilde RE, et al. Effect of growth rate from 6 to 16 months of age on sexual development and reproductive function in beef bulls. Theriogenology 2012;77:13981405.

    • Search Google Scholar
    • Export Citation
  • 4. Arteaga A, Baracaldo M, Barth A. The proportion of beef bulls in western Canada with mature spermiograms at 11 to 15 months of age. Can Vet J 2001;42:783787.

    • Search Google Scholar
    • Export Citation
  • 5. Chenoweth P, Sanderson M. Breeding bull selection, assessment, and management. In: Chenoweth PJ, ed. Beef practice: cow-calf production medicine. Ames, Iowa: Blackwell Publishing, 2005;151174.

    • Search Google Scholar
    • Export Citation
  • 6. Ellis RW, Rupp GP, Chenoweth PJ, et al. Fertility of yearling beef bulls during mating. Theriogenology 2005;64:657678.

  • 7. Chenoweth P. Reproductive selection of males: current and future perspectives. Rev Bras Reprod Anim 2011;35:133138.

  • 8. Thundathil JC, Dance AL, Kastelic JP. Fertility management of bulls to improve beef cattle productivity. Theriogenology 2016;86:397405.

    • Search Google Scholar
    • Export Citation
  • 9. Rawlings N, Evans AC, Chandolia RK, et al. Sexual maturation in the bull. Reprod Domest Anim 2008;43(suppl 2):295301.

  • 10. Lunstra DD, Echternkamp SE. Puberty in beef bulls: acrosome morphology and semen quality in bulls of different breeds. J Anim Sci 1982;55:638648.

    • Search Google Scholar
    • Export Citation
  • 11. Lunstra DD. Testicular development and onset of puberty in beef bulls. Beef Research Program Progress Report No 1. Clay Center, Neb: US Meat Animal Research Center, 1982;2627.

    • Search Google Scholar
    • Export Citation
  • 12. Chenoweth PJ, Chase CC Jr, Thatcher MJ, et al. Breed and other effects on reproductive traits and breeding soundness categorization in young beef bulls in Florida. Theriogenology 1996;46:11591170.

    • Search Google Scholar
    • Export Citation
  • 13. Johnson KR, Dewey CE, Bobo JK, et al. Prevalence of morphologic defects in spermatozoa from beef bulls. J Am Vet Med Assoc 1998;213:14681471.

    • Search Google Scholar
    • Export Citation
  • 14. Hopkins FM, Spitzer JC. The new Society for Theriogenology breeding soundness evaluation system. Vet Clin North Am Food Anim Pract 1997;13:283293.

    • Search Google Scholar
    • Export Citation
  • 15. Barth AD, Waldner CL. Factors affecting breeding soundness classification of beef bulls examined at the Western College of Veterinary Medicine. Can Vet J 2002;43:274284.

    • Search Google Scholar
    • Export Citation
  • 16. Chase CC Jr, Chenoweth PJ, Larsen RE, et al. Growth and reproductive development from weaning through 20 months of age among breeds of bulls in subtropical Florida. Theriogenology 1997;47:723745.

    • Search Google Scholar
    • Export Citation
  • 17. Coe PH. Associations among age, scrotal circumference, and proportion of morphologically normal spermatozoa in young beef bulls during an initial breeding soundness examination. J Am Vet Med Assoc 1999;214:16641667.

    • Search Google Scholar
    • Export Citation
  • 18. Kastelic JP, Thundathil JC. Breeding soundness evaluation and semen analysis for predicting bull fertility. Reprod Domest Anim 2008;43(suppl 2):368373.

    • Search Google Scholar
    • Export Citation
  • 19. Lunstra DD, Ford J, Echternkamp S. Puberty in beef bulls: hormone concentrations, growth, testicular development, sperm production and sexual aggressiveness in bulls of different breeds. J Anim Sci 1978;46:10541062.

    • Search Google Scholar
    • Export Citation
  • 20. Madrid N, Ott RS, Veeramachaneni DN, et al. Scrotal circumference, seminal characteristics, and testicular lesions of yearling Angus bulls. Am J Vet Res 1988;49:579585.

    • Search Google Scholar
    • Export Citation
  • 21. Neville WE Jr, Williams DJ III, Richardson KL, et al. Relationship of breeding soundness evaluation score and its components with reproductive performance of beef bulls. Theriogenology 1988;30:429436.

    • Search Google Scholar
    • Export Citation
  • 22. Menon A, Barkema H, Wilde R, et al. Associations between sperm abnormalities, breed, age, and scrotal circumference in beef bulls. Can J Vet Res 2011;75:241247.

    • Search Google Scholar
    • Export Citation
  • 23. Persson Y, Soderquist L. The proportion of beef bulls in Sweden with mature spermiograms at 11–13 months of age. Reprod Domest Anim 2005;40:131135.

    • Search Google Scholar
    • Export Citation
  • 24. Bruner K, McCraw RL, Whitacre MD, et al. Breeding soundness examination of 1, 952 yearling beef bulls in North Carolina. Theriogenology 1995;44:129145.

    • Search Google Scholar
    • Export Citation
  • 25. Higdon HL, Spitzer JC, Hopkins FM, et al. Outcomes of breeding soundness evaluation of 2898 yearling bulls subjected to different classification systems. Theriogenology 2000;53:13211332.

    • Search Google Scholar
    • Export Citation
  • 26. Kennedy SP, Spitzer JC, Hopkins FM, et al. Breeding soundness evaluations of 3,648 yearling beef bulls using the 1993 Society for Theriogenology guidelines. Theriogenology 2002;58:947961.

    • Search Google Scholar
    • Export Citation
  • 27. Wolf FR, Almquist JO, Hale EB. Prepuberal behavior and puberal characteristics of beef bulls on high nutrient allowance. J Anim Sci 1965;24:761765.

    • Search Google Scholar
    • Export Citation
  • 28. Barth A. Bull breeding soundness. 3rd ed. Saskatoon, SK, Canada: Western Canadian Association of Bovine Practitioners, 2013;108118.

    • Search Google Scholar
    • Export Citation
  • 29. Cates W, Nicholson H, Crow G, et al. Testicular development in record of performance bulls, in Proceedings. Annu Meet Soc Theriogenol 1981;1630.

    • Search Google Scholar
    • Export Citation
  • 30. Almquist JO, Branas RJ, Barber KA. Postpuberal changes in semen production of Charolais bulls ejaculated at high frequency and the relation between testicular measurements and sperm output. J Anim Sci 1976;42:670676.

    • Search Google Scholar
    • Export Citation
  • 31. Evans AC, Davies FJ, Nasser LF, et al. Differences in early patterns of gonadotrophin secretion between early and late maturing bulls, and changes in semen characteristics at puberty. Theriogenology 1995;43:569578.

    • Search Google Scholar
    • Export Citation

Advertisement

Factors associated with yearling bulls passing subsequent breeding soundness evaluations after failing an initial evaluation

View More View Less
  • 1 Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506.
  • | 2 Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506.
  • | 3 Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506.
  • | 4 Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506.
  • | 5 Kansas Artificial Breeding Service Unit, 3171 Tuttle Creek Blvd, Manhattan, KS 66502.

Abstract

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 any factors at initial BSE that predicted satisfactory performance at reevaluation.

DESIGN Retrospective observational study.

ANIMALS 2,064 beef bulls between 11 and 14 months of age at first BSE, evaluated from 2006 to 2014.

PROCEDURES For each bull, data on age (categorized by month), breed, and BSE findings were extracted from the medical records. Bulls were classified as satisfactory potential breeders if they met Society for Theriogenology standards at the initial BSE or up to 2 subsequent reevaluations. Generalized linear mixed models were generated to assess potential associations between certain variables at initial BSE and passing that evaluation or passing subsequent BSEs after initial failure.

RESULTS 1,921 of 2,064 (93.1%) yearling bulls passed 1 of up to 3 BSEs. The proportion of yearling bulls that were not classified as satisfactory during initial BSE but were later classified as satisfactory was 143 of 287 (49.8%). A significant interaction was identified between bull age and breed in the probability of passing the initial evaluation. No variable, including breed, age, scrotal circumference per day of age, and spermatozoa morphology at initial BSE, significantly predicted passing subsequent reevaluations after failing an initial BSE.

CONCLUSIONS AND CLINICAL RELEVANCE Age and breed information should be considered when deciding the age at which initial BSE should be scheduled for a yearling bull cohort.

Abstract

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 any factors at initial BSE that predicted satisfactory performance at reevaluation.

DESIGN Retrospective observational study.

ANIMALS 2,064 beef bulls between 11 and 14 months of age at first BSE, evaluated from 2006 to 2014.

PROCEDURES For each bull, data on age (categorized by month), breed, and BSE findings were extracted from the medical records. Bulls were classified as satisfactory potential breeders if they met Society for Theriogenology standards at the initial BSE or up to 2 subsequent reevaluations. Generalized linear mixed models were generated to assess potential associations between certain variables at initial BSE and passing that evaluation or passing subsequent BSEs after initial failure.

RESULTS 1,921 of 2,064 (93.1%) yearling bulls passed 1 of up to 3 BSEs. The proportion of yearling bulls that were not classified as satisfactory during initial BSE but were later classified as satisfactory was 143 of 287 (49.8%). A significant interaction was identified between bull age and breed in the probability of passing the initial evaluation. No variable, including breed, age, scrotal circumference per day of age, and spermatozoa morphology at initial BSE, significantly predicted passing subsequent reevaluations after failing an initial BSE.

CONCLUSIONS AND CLINICAL RELEVANCE Age and breed information should be considered when deciding the age at which initial BSE should be scheduled for a yearling bull cohort.

Supplementary Materials

    • Supplementary Table S1 (PDF 79 kb)
    • Supplementary Table S2 (PDF 77 kb)
    • Supplementary Table S3 (PDF 78 kb)
    • Supplementary Table S4 (PDF 78 kb)

Contributor Notes

Address correspondence to Dr. Monday (jessie.monday@tvmdl.tamu.edu).

Dr. Monday's present address is Texas A&M Veterinary Medical Diagnostic Lab–Amarillo, 6610 W Amarillo Blvd, Amarillo, TX 79106.

Dr. Theurer's present address is Veterinary Research and Consulting Services, 4413 Larned Cir, Hays, KS 67601.