Successful use of a gonadotropin-releasing hormone (GnRH) analog for the treatment of tertiary hypogonadism (GnRH deficiency) in a 5-year-old Belgian Blue bull

Abstract

A bull was referred for a progressive oligoasthenotheratozoospermia that resulted in a unsuitable seminal quality for the cryopreservation. Breeding soundness evaluation results suggested gonadal dysfunction. Because of the lack of normal ranges for these hormones in the bull, in this study, the hypogonadism and the site of the dysfunction (hypothalamus) were diagnosed by the gonadotropin-releasing hormone (GnRH) stimulation test. The evaluation of pituitary and testicular responsiveness by a GnRH stimulating test revealed a responsiveness of the pituitary and testis, thus a secondary hypogonadism (hypothalamic hypogonadism) was postulated and a therapeutic approach based on the subcutaneous administration of GnRH analog was attempted. An increase in semen volume, concentration and sperm characteristics were detected 9 weeks after the start of the treatment, corroborating the hypothalamic origin of the disease and the useful of the GnRH therapy.[...

Effect of Hormonal Administration on Reproductive Development of Holstein Bull Calves and Concomitant Changes in Semen Characteristics and Seminal Plasma

“…In our study, bulls treated with GnRH showed better semen characteristics than other groups. This is in agreement with Contri et al (2012), who reported that the continuous administration of a low dose of a GnRH analog resulted in recovery of the function of the testis, in corroboration with the improvement of semen characteristics to normal within 9 weeks. As a consequence, the time necessary to improve semen quality in the treated bull being 8-9 weeks corresponds to the time spermatogenesis takes as reported in the literature (Barth and Oko, 1989).…”

“…From the age of 18 months, the bull was successfully used for semen production in an artificial insemination center. However, at late age, the bull showed a progressive decrease in semen characteristics that involved sperm concentration and volume, motility and sperm abnormalities that resulted in an unsuitable quality of semen for cryopreservation (Contri et al, 2012). If the animals reach puberty and sexual maturity at early age, more benefit would be obtained from their productive life.…”

“…Screening of the semen at initial stages can provide insight into the fertilizing capacity of the spermatozoa (Januskauskas and Zilinskas, 2002). A few studies on the effect of GnRH on semen characteristics in cow bulls are available (Sajjad et al, 2007;Contri et al, 2012). The time necessary to improve semen quality in the treated bull being 8-9 weeks corresponds to the time spermatogenesis takes (Barth and Oko, 1989).…”

Pulse wave Doppler ultrasound of testicular arteries and their relationship with semen characteristics in healthy bulls

“…Classically, the evaluation of the testicular function of the bull always includes semen analysis [ 49 ]. All diseases localized in the testis (orchitis, hypoplasia, degeneration, hypogonadism, torsion, neoplasia) may cause a reduction in the quality of semen [ 50 , 51 ]. However, the evaluation of the seminal material provide information on the spermatogenesis started about 61 d before [ 2 , 52 , 53 ].…”

Semen Quality of Ongole Crossbred Bull with Gonadotropin Realizing Hormone (GnRH) Treatment

“…This study used 18 Ongole Crossbred bulls at the age of 3-5 years with a motility condition of ≤40% (Contri et al, 2012). Semen was collected using an artificial vagina.…”