Reproductive Features and Faecal Progesterone Metabolite Profile in Female Ferrets

Abstract

Elevated post-partum progesterone metabolite (P(4) -met) levels have been recently postulated to occur in lactating lynxes. The aims of this study were to monitor reproductive features in female ferrets, changes in the faecal P(4) -met concentrations throughout the breeding season and ovarian activity in post-partum lactating and non-lactating (NL) female ferrets. Our results indicate that coinciding with the results described in the lynx, elevated faecal P4-met concentrations occur in lactating ferrets, furthermore, that the duration of elevated secretion of P(4) seems to be dependent on the duration of lactation (P4-met at delivery, n=47: <500 ng/g; 5-7 days after delivery, during lactation, n=47: ≥ 500-800 ng/g; in females weaned at delivery, n=4: baseline levels). Three days after ovariohysterectomy of lactating females, P(4) -met concentrations decreased to baseline levels. In lactating females, the ovarian stroma is more active than that in NL ones implicating that the ovary is at least in part responsible for the elevated P4-met concentrations. Ovaries of lactating females contained many luteinized cells either as luteinized granulose cells in the wall of late pre-antral/early antral follicles or as corpus luteum (CL)-like structures. Early resumption of the entire ovarian activity (developed follicles and oestrus) occurs in NL post-partum females, while final follicular development is blocked (follicles stalls at antral stage) in the lactating ones (however, occasionally lactational oestrus may occur). We suppose that the elevated faecal P4-met during lactation together with suckling and other hormonal effects may contribute to prevention of early returning to oestrus in nursing female ferrets.

Seasonal Change in Adiponectin Associated with Ovarian Morphology and Function in Wild Ground Squirrels (Citellus dauricus Brandt)

“…This illustrates that the ovary is arrested in follicular development during the non-breeding season, at which time, it has no dominant follicle and does not ovulate. Similar changes in ovary morphology have been reported in other seasonal breeding animals, including water voles, golden hamsters, and ferrets [ 33 , 34 , 35 ]. The ovarian and uterine weights of water voles exhibit significant annual rhythms, with the ovaries being heavier and presenting the maximum number of corpora lutea during the breeding season [ 33 ].…”