Lukola A, Sundqvist C
J Endocrinol Invest. 1986 Jun;9(3):243-4. doi: 10.1007/BF03348109.
A group of 12 sterile, azoospermic mink males were treated with clomiphene citrate (10 mg/kg/day) for 10 days during the mating season; 50% of the males showed improved sperm counts already after 2 days of treatment and the maximum effect was seen 4-6 days after the start of the treatment. The other half of the group did not respond to the treatment and their sperm counts remained near zero during the whole experiment.