The testes in horses are reproductive organs responsible for the production of sperm and the secretion of hormones such as testosterone. Located in the scrotum, the testes play a vital role in male fertility and reproductive behavior. They consist of seminiferous tubules where spermatogenesis occurs, and interstitial cells, also known as Leydig cells, which produce testosterone. The function and health of equine testes can be influenced by factors such as age, season, and overall health status. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, physiology, and pathology of the testes in horses, providing insights into their role in equine reproduction and breeding management.
Serum anti-Müllerian hormone (AMH), a marker of equine cryptorchidism, is detectable in intact and cryptorchid stallions but not in geldings because it is secreted from Sertoli cells. A 4-year-old uncastrated Thoroughbred racehorse had no visible testes; therefore, the horse was considered a bilateral cryptorchidism. However, the serum AMH was undetectable (<0.08 ng/ml). Human chorionic gonadotrophin (hCG) stimulating test result indicated that the horse was a gelding. The results of sex chromosomal analysis and sequence analysis of SRY gene suggested that the horse was a genetically-intac...
Hoshiba H, Sinowatz F.Spermadhesins are proteins with various functions in sperm capacitation and zona pellucida binding. In this study the cellular localization of the spermadhesin AWN-1 has been examined in the equine male genital tract. Results obtained by immunohistochemical methods reveal that in the horse AWN-1 is synthesized in spermatogonia, in the rete testis, the ductus epididymidis and the seminal vesicles. These findings indicate that the cellular origin of spermadhesins is species-specific.
Talluri TR, Jhamb D, Paul N, Singh J, Dedar RK, Mehta SC, Legha RA, Pal Y.The recovery of spermatozoa from the cauda epididymis may be the only option to obtain genetic material from elite stallions that had undergone castration or sudden death due to colic or severe injury. Objective: To evaluate two different protocols for retrieval of stallion epididymal spermatozoa and to evaluate different cryoprotectants on the freezability of the epididymal spermatozoa. Methods: Six epididymides from three stallions were collected immediately after routine castration under general anesthesia. In the first experiment, each epididymis (of two testes) of the same stallion were p...
Bucci R, De Amicis I, Parrillo S, Robbe D, Carluccio A.Good sperm production is a notable requirement for subjects intended for reproduction, particularly in endangered species, and it has been demonstrated that in horse stallions, this is correlated to testicular volume. The present study, which involved Martina Franca jacks, aimed to determine whether, also in this endangered breed, there is a correlation between the total sperm number (TSN) and testicular volume. Testes were measured with both ultrasound and a caliper. Testicular volume was calculated using two different formulas: one representing the volume of an ellipsoid and one developed to...
Cinone M, Albrizio M, Guaricci AC, Lacitignola L, Desantis S.Heat shock proteins are the most evolutionarily conserved protein families induced by stressors including hyperthermia. In the context of pathologies of the male reproductive tract, cryptorchidism is the most common genital defect that compromises the reproductive potential of the male because it induces an increase in intratesticular temperature. In equine species, cryptorchidism affects almost 9 % of newborns and few studies have been carried out on the molecular aspects of the retained testis. In this study, the expression pattern of HSP60, 70, and 90 in abdominal and inguinal testes, in t...
Shakeel M, Choi Y, Yoon M.Cryptorchidism affects spermatogenesis and testis development, often resulting in stallion subfertility/infertility. This study aims to identify the specific germ cells impacted by cryptorchism in stallions. In a previous study, we found that PGP9.5 and VASA are molecular markers expressed in different germ cells within stallions. Herein, we assessed the heat stress-induced response of spermatogonial stem cells (SSCs) in the seminiferous tubules (ST) of cryptorchid stallion testes (CST) and normal stallion testes (NST). This goal was accomplished by comparing PGP9.5 and VASA expression pattern...
Johnson SA, Sikes KJ, Johnson JW, Van Zeeland E, Wist S, Santangelo KS, King MR, Frisbie DD.Low load exercise training with blood flow restriction (BFR) has become increasingly used by human physical therapists to prescribe controlled exercise following orthopaedic injury; its effects on the equine superficial digital flexor tendon (SDFT), however, are unknown. Objective: To investigate outcomes of pressure specific BFR walking exercise on uninjured equine SDFT biomechanics and histomorphology. Methods: Controlled in vivo experiment. Methods: Four forelimbs of four horses were exposed to 40 BFR-walk sessions (10-min interval walking) on a treadmill over a 56-day study period with the...
