Exogenous gonadotropin releasing hormone (GnRH) modulates scrotal and testicular biometrics, libido, endocrinological and heamatological profiles in Ganjam goat under humid tropical coastal ecosystem of Odisha

Abstract

Objective: To assess the effect of exogenous gonadotropin releasing hormone (GnRH) in libido, scrotal and testicular biometrics, endocrinological and heamatological profiles of Ganjam goat buck during winter and pre-monsoon seasons. Methods: Forty eight healty Ganjam goat bucks of 3-4 years old were equally divided into the control and treatment groups. The control group received distilled water as placebo, while the treatment group received GnRH injection (4 μg Buserelin acetate/mL) once a week for four months. Body weight, scrotal circumference and testicular parameters (testicular volume, testicular weight and testis index), endocrinological profiles [follicle stimulating hormone (FSH), luteinizing hormone (LH), and testosterone], sex behavioural profiles (libido score, mating ability score, and sex behavioural score) and heamatological profiles (red blood cells, white blood cells, haemoglobin, and packed cell volume) were estimated. Results: The libido, scrotal and testicular biometrics, and endocrinological profiles significantly differed between the control and GnRH-treated bucks within and between the seasons within the two groups (P<0.05). Body weight, scrotal circumference, testicular volume, testicular weight, testis index, FSH, LH, testosterone, libido score, mating ability score, sex behavioural score, red blood cells, haemoglobin and packed cell volume were significantly higher in the GnRH-treated bucks compared to the control bucks in pre-monsoon and winter seasons (P<0.05). Body weight, scrotal circumference, testicular volume, testicular weight, testis index, FSH, LH, testosterone, libido score, mating ability score, sex behavioural score, red blood cell counts (in treatment), and haemoglobin were significantly higher in pre-monsoon compared to winter season in the experimental groups (P<0.05). The white blood cell counts neither differed between seasons nor between the two groups. Conclusions: Exogenous GnRH supplementation and pre-monsoon season have higher beneficial effects in improvement of endocrinological profiles with cascading beneficial effects on scrotal circumference, testicular volume, testicular weight, and sex behavioural profiles, which in turn will improve the sperm production and its cryo-survivability and fertility rate in Ganjam goat.

Effect of Seasonal Variation on the Hormonal Profile of West African Dwarf (WAD) Goats

“…Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are essential for spermatogenesis and androgen synthesis. Observed results in WAD bucks differed from the findings of Ponraj et al (2022), who reported "that Season has a significant effect on endocrinological profiles and libido scores in male Andaman local goats, which in turn induces significant effects on the production and reproduction performances. Goats in Andaman and Nicobar Islands are perennial breeders; however, available literature speculates that some seasonality prevailed as similar to other tropical goat breeds" while the performance of does in regards to the tested hypothesis agreed with the findings of Ponraj et al (2022).…”

“…Observed results in WAD bucks differed from the findings of Ponraj et al (2022), who reported "that Season has a significant effect on endocrinological profiles and libido scores in male Andaman local goats, which in turn induces significant effects on the production and reproduction performances. Goats in Andaman and Nicobar Islands are perennial breeders; however, available literature speculates that some seasonality prevailed as similar to other tropical goat breeds" while the performance of does in regards to the tested hypothesis agreed with the findings of Ponraj et al (2022). This shows that despite variations in sample size, location of the experiment, and differences in breeds, amongst other pertinent factors, seasonality is a significant factor that influences the productivity of WAD goats and hence must be factored into the management equation and breeding objectives to boost productivity.…”

“…Several studies along this line are available in the extant literature (Salles et al, 2020;Ponraj et al, 2022); however, paucity in the number of such studies on the indigenous breed of goats in Nigeria remains a glaring fact. Furthermore, the prevailing climate change issues are of utmost importance, bringing different stimuli and stressors compared to historical records (Daramola et al, 2021).…”

The role ofGnRHin Tibetan male sheep and goat reproduction

“…Testicular activity is controlled by gonadotropins, LH and FSH are released to activate their receptors expressed on Leydig cells and Sertoli cells, respectively, to stimulate testosterone (T) secretion and spermatogenesis in testis (Bernard, 2022). Various factors, including nutrition and photoperiod, influence testicular size by the regulatory effect of gonadotrophins, LH and FSH (Ponraj et al, 2022). Recently, it has been shown that the gut microbiota is a crucial regulator of reproductive hormonal function, androgen production, and metabolism and may regulate spermatogenesis.…”