Deslorelin treatment of hyperoestrogenism in neutered ferrets (Mustela putorius furo): a case report

Hyperoestrogenism causing progressive alopecia in neutered ferrets may be induced by ovarian remnant syndrome (ORS) and nodular hyperplasia of the adrenocortex (hyperadrenocorticism, NHA). The objective of the study was to determine whether a slow-release implant of a gonadotropin releasing hormone (GnRH) analogue, deslorelin, has any value in therapy of hyperoestrogenism of adrenocortical origin (NHA). Three supposed cases of NHA with alopecia and other clinical signs of hyperoestrogenism (n = 2 spayed females in oestrous and n = 1 castrated male) were treated with a subcutaneous implant of 4.7 mg deslorelin acetate. Blood samples were collected, and plasma levels of estradiol (E2) were determined just before, and some weeks after treatment. For realistic monitoring, blood samples for E2 determination were also taken from intact, healthy (untreated control) females after the beginning of heat (n = 5), or 9–21 days after, with hCG induced ovulation (n = 6), or out of breeding season (n = 3). Before treatment, all three alopecic ferrets showed elevated E2 concentrations (99.45–139.9 pmol/l) similar to the untreated control females in oestrous (61.6–123.02 pmol/l) (P = 0.229). Some weeks after the deslorelin administration, the hair of these ferrets began to grow again and the elevated E2 concentrations significantly decreased compared to the pre-treatment values (P = 0.035). E2 concentrations reached the basal level (12.89–16.08 pmol/l) typical for that of the untreated control females in anoestrus or in luteal phase (12.0–30.58 pmol/l) (P = 0.137). All treated ferrets were examined again 19–21 months after implant insertion (the implant still being present) and all of them had normal hair and were clinically healthy. These observations prove that deslorelin can suppress the E2 production of NHA, and is therefore a useful tool in the therapy of hormonal alopecia neutered ferrets.