Abstract
The objectives of this study were: a) establish the frequency, age and reason for hemicastration, b) determine the most frequently removed testicle and c) compare the athletic performance between unilaterally castrated and intact Chilean rodeo stallions. Two hundred and sixteen Chilean Horse stallions participating in the 2016 Chilean rodeo qualifying rounds and National Championship (CRNC) were evaluated. Owners and/or riders were interrogated about age, hemicastration, age at hemicastration, removed testicle, reason and effects of hemicastration on athletic performance of stallions. The statistical analysis was descriptive and the results were expressed in means and percentages. Chi-square test was used to compare the performance between unilaterally castrated and intact stallions. Performance was qualified based on qualification to the CRNC and ultimately participation in the Champion series. Fifty-three percent of the stallions were unilaterally castrated (47% left testicle; 53% right testicle) (P>0.05). Mean age of hemicastration was 6.97±2.24 years. Main reasons reported for hemicastration were: traumatic (76%), increased volume (13%) and preventive (11%), but not all of them with medical confirmation. Seven owners or riders were unaware of the reason of hemicastration. Forty-six percent of the qualified stallions to the CRNC (P>0.05) and 29% of the qualified to the Champion series were unilaterally castrated (P=0.0122). It was concluded that half of the 2016 elite Chilean Horse stallions were unilaterally castrated, without preference for a testicle, after the age of initiation of sporting activity. A 43.5% of hemicastration in Chilean rodeo stallions are performed preventively or based on subjective assessments of owners and riders without veterinary diagnosis, however, it is unclear that hemicastration affected the athletic performance in these cases.
Downloads
References
- Apaoblaza SA. 2015. Encuesta sobre ablación testicular unilateral en potros pura raza chilena en las regiones de La Araucanía y Los Ríos. Memoria de título, Universidad Austral de Chile, Facultad de Ciencias Veterinarias. Valdivia, Chile.
- Arancio A. 2016. Anuario Federación de Criadores de Caballos Chilenos 2016. 18a ed. Ograma, Santiago, Chile.
- Cox JE, Edwards GB, Neal PA. 1979. An analysis of 500 cases of equine cryptorchidism. Equine Vet J 11, 113-116.
- de Ban NE. 1970. Castration of horses and complications arising from this procedures. Vet Rec 87, 502-504.
- Green P. 2001. Castration techniques in the horse. In Practice 23, 250-261. Hartman R, Hawkins JF, Adams SB, Moore GE, Fessler JF. 2015. Cryptorchidectomy in equids: 604 cases (1977-2010). J Am Vet Med Assoc 246, 777-784.
- Hoagland TA, Ott KM, Dinger JE, Mannen K, Woody CO, et al. 1986. Effects of unilateral castration on morphologic characteristics of the testis in one-, two-, and three-year-old stallions. Theriogenology 26, 397-405.
- Huppes T, Stout TAE, Ensink JM. 2017. Decision making for cryptorchid castration: a retrospective analysis of 280 cases. J Equine Vet Sci 48, 73-81.
- Lu KG. 2005. Clinical diagnosis of the cryptorchid stallion. Clin Tech Equine Pract 4, 250-256.
- Marshall JF, Moorman VJ, Moll HD. 2007. Comparison of the diagnosis and management of unilaterally castrated and cryptorchid horses at referral hospital: 60 cases (2002-2006). J Am Vet Med Assoc 231, 931-934.
- Maxwell JAL. 2005. Equine hemi-castration: review of the condition, prevalence, etiology, diagnosis and surgical management. Aust Vet J 83, 203-207.
- McCormick JD, Valdez R, Rakestraw PC, Varner DD, Blanchard TL, et al. 2012. Effect of surgical technique for unilateral orchiectomy on subsequent testicular function in miniature horse stallions. Equine Vet J 44 (Suppl 43), 100-104.
- Moll HD, Pelzer KD, Pleasant RS, Modransky PD, May KA. 1995. A survey of equine castration complications. J Equine Vet Sci 15, 522-526.
- Montory A. 2016. Historia del rodeo chileno. Tomo I. Federación del Rodeo Chileno. Santiago, Chile.
- Mora-Carreno M, Briones R, Galecio JS, Parra D, Rosenfeld C, et al. 2014. Main musculoskeletal injuries associated with lameness in Chilean rodeo horses. Arch Med Vet 46, 419-424.
- Mueller POE, Parks AH. 1999. Crytorchidism in horses. Equine Vet Educ 11, 77-86.
- Muñoz-Alonzo L, Morales F, Ortiz R, Cruces J, Briones M, et al. 2016. Medición testicular en sementales de raza caballo chileno enteros y castrados unilateralmente. Rev Inv Vet Perú 27, 303-308. Parlevliet JM, Kemp B, Colenbrander B. 1994. Reproductive characteristics and semen quality in maiden Dutch warmblood stallions. J Reprod Fert 100, 183-187.
- Searle D, Dart AJ, Dart CM, Hodgson DR. 1999. Equine castration: review of anatomy, approaches, techniques and complications in normal, cryptorchid and monorchid horses. Aust Vet J 77, 428-434.
- Stout T, Colenbrander B. 2011. Reproductive parameters of draft horse, friesian and warmblood stallions. In: McKinnon AO, Squires EL, Vaala WE, Varner DD (eds). Equine Reproduction. Vol 1. 2nd ed. Wiley-Blackwell, Chichister, UK, Pp 1362-1366.
- Trotter GW. 1993. Unilateral castration. In: McKinnon AO, Voss JL (eds). Equine Reproduction. Lea & Febiger. Philadelphia, USA, Pp 921-924.
- Varner DD, Schumacher J. 1998. Enfermedades del aparato reproductivo: el padrillo. In: Colahan P, Mayhew I, Merritt A, Moore J (eds). Medicina y Cirugía Equina. Vol II. 4a ed. Inter-Médica, Buenos Aires, Argentina, Pp 773-789.
