Testicular measures in entire and unilaterally castrated Chilean horse breed stallions

• Autores: Muñoz-Alonzo, Lisandro, Morales Quintana, Felipe, Ortiz Ramírez, Reinaldo, Cruces Leal, Jaime, Briones Luengo, Mario, Saravia Ramos, Fernando
• Formato: artículo
• Fecha de Publicación: 2016
• Institución: Universidad Nacional Mayor de San Marcos
• Repositorio: Revistas - Universidad Nacional Mayor de San Marcos
• Lenguaje: español
• OAI Identifier: oai:ojs.csi.unmsm:article/11662
• Enlace del recurso: https://revistasinvestigacion.unmsm.edu.pe/index.php/veterinaria/article/view/11662
• Nivel de acceso: acceso abierto
• Materia: testicular volume; daily sperm production; equine; volumen testicular; producción espermática diaria; equino

The aim of this study was to determine the testicular size and to estimate the daily sperm production (DSP) in entire and unilaterally castrated males of the Chilean Horse breed. Sixty one (31 entire and 30 unilaterally castrated) stallions, with ages between 3 and 20 years of age were studied. A scrotal caliper was used to measure height, width and length of testicles. Testicular volume (TV) was calculated and DSP was estimated using formulae proposed by Sertich (2011).  Testicular measures in entire stallions were larger than expected and without statistical difference between testicles. The estimated DSP in entire stallions was 7.67 ± 2.32 x 109 spermatozoa. There were no differences in size related to the remaining testicle in unilaterally castrated stallions, but height, width and TV were larger than in entire stallions (p<0.05). DSP in unilaterally castrated stallions was 5.13 ± 1.84 x 109 spermatozoa, and it was a 33% lower compared to entire males (p<0.0001). Results obtained allow concluding that testicular measures in Chilean Horse stallions are larger than expected for their body size.