The purpose of the current study was to determine the concentrations of adiponectin and
testosterone in various ages of bucks as well as the correlations of adiponectin and testosterone with
semen quality as an indicator of fertility. Nineteen Anglo Nubian (AN) x Etawah Grade (PE) (Anpera)
crossbred bucks belonged to the Research Institute for Animal Production were classified into four
different age groups: 24 months, 30 months, 36 months, and more than 48 months. The concentrations
of adiponectin and testosterone in the samples of blood plasma were analyzed using enzyme-linked
immunosorbent assay (ELISA). The semen characteristics were evaluated both macroscopically
and microscopically. The results of the study showed that plasma concentrations of adiponectin
in Anpera bucks at the ages of 24, 30, 36, and more than 48 months were 14.10±1.73 mg/L, 18.36±8.25
mg/L, 20.38±8.67 mg/L, and 15.41±7.31 mg/L, respectively. There was no significant difference in
adiponectin concentrations among the age groups (p>0.05). However, there were correlations of
adiponectin concentrations with semen volume, sperm morphology, and sperm concentration. Plasma
concentrations of testosterone at the ages of 24, 30, 36, and more than 48 months were 9.76±2.46 ng/
mL, 9.81±1.56 ng/mL, 10.05±0.94 ng/mL, and 9.93±2.71 ng/mL, respectively. Plasma concentrations of
testosterone in Anpera bucks also did not demonstrate a significant difference among the age groups
(p>0.05). However, plasma testosterone concentrations had significant correlations with semen volume,
sperm motility, and sperm concentration. In conclusion, the plasma concentrations of adiponectin
and testosterone hormones had correlations with the semen quality parameters, which are related to
fertility.