Seasonal Changes in Serum Testosterone, LDH Concentration and Semen Characteristics in Markhoz Goats

Abstract

This experiment was conducted to study variations of serum testosterone and seminal characteristics of Markhoz male goats. Blood samples were obtained via jugular vein, and semen was collected by using an artificial vagina from 14 fertile male goats (2–3 years of age), at 15-day intervals starting on 15 July and ending on 30 October 2010 (during breeding and non-breeding season). Semen volume, total sperm (volume×concentration), live sperm (%), abnormal sperm (%) and semen pH were significantly superior during the late summer and early autumn (breeding season). Variation of sperm density, motility and progressive motility was not significant during the sampling period. The results presented show that the lowest and highest levels of lactate dehydrogenase in the seminal plasma were recorded in late October (2.82 U/ml) and in late August (4.81 U/ml), respectively. Moreover, the study indicated that the serum testosterone concentration was higher during late summer and early autumn (p<0.05) than at any other of sampling period. There were negative correlations between volume and sperm density (−0.135, p<0.05), and positive correlations between volume and percentage live sperm (0.224) and percentage progressive motility (0.194, p<0.01). Sperm density was correlated with live sperm (0.200, p<0.05) and progressive motility (0.202, p<0.01). The correlation between live sperm and progressive motility was 0.554 (p<0.01). Furthermore, the results in this study indicated a significant positive correlation between live sperm and LDH (0.450) and a negative correlation between sperm density and LDH concentration (−0.272) (p<0.01). Significant, but positive correlations were found between sperm motility and LDH (0.542) and testosterone concentration (0.522), respectively (p<0.05). In conclusion, this study demonstrated that the best obtained semen was collected in late summer (during decreasing photoperiod) and early autumn (September and October). This also coincides with the natural breeding season of Markhoz goats in Iran.

Correlation of biochemical constituents of seminal plasma with semen quality in Teddy goat (Capra hircus) bucks

“…Individual motility percentage in the present study was 89.18 ± 0.37. These findings are in close harmony with Zubair, Ahmad, Jamil, and Deeba () and Farshad, Yousefi, Moghaddam, and Khalili (). However, motility percentage found in this study was lower than the reported values (96.35% ± 0.9%) of Oliveira et al.…”

The Effect of Season on Spermatozoa Motility, Plasma Membrane and Acrosome Integrity in Fresh and Frozen–Thawed Semen from Xinong Saanen Bucks

“…Relatively higher quality of semen of Markhoz bucks during the late summer and early autumn was reported by Farshad et al. (), which might be related to the period of daylight. Zaraibi bucks also have displayed poorest efficiency during winter and spring, which hinders implementation of intensive goat breeding systems (Barkawi et al.…”

“…; Farshad et al. ). In the present experiment, the sperm concentration followed a tendency opposite to that of the ejaculate volume during spring, summer and autumn.…”

Seminal characteristics, libido and serum testosterone concentrations in mixed-breed goat bucks receiving testosterone during the non-breeding period

“…Reaction time and ejaculate characteristics (mean ± SD) in mixed-breed goat bucks either subjected to testosterone treatment or left untreated during the period of sexual inactivity (March) at 26°N. Farshad et al (2012) with Markhoz goat bucks. Figure 1 summarizes various sexual behaviours of bucks during the exposure period to estrogenized does.…”