Delayed Implantation in Roe Deer (Capreolus Capreolus)

Abstract

The results presented in this paper indicate that delayed implantation in the roe deer is due to a lack of certain essential factors which are needed to induce and support the process of embryonic growth. These factors are eventually supplied, in the first weeks of January, as a secretion emanating from the endometrial glands. This secretion contains uterine-specific and serum proteins, about twenty free amino acids, protein-bound glucose and galactose and, rather surprisingly, a free ketose which appears to be fructose. Elongation of the roe deer blastocyst is also correlated with a rise in the concentration of plasma oestrogens, an endocrine change that may stimulate the endometrial glands into secretory activity. However, since simultaneous changes were not observed in the ovaries, the elevated oestrogen levels may be a consequence rather than a cause of embryonic growth.

Changes in the protein content of mouse uterine flushings during normal pregnancy and delayed implantation, and after ovariectomy and oestradiol administration

“…The results obtained in this study support observations made on the fur seal (Daniel, 1971), rat (Surani, 1975), roe deer (Aitken, 1974a(Aitken, , b, 1975 and wallaby (Renfree, 1973) in associating embryonic diapause with a lack of proteinaceous material within the uterine lumen. A causal relationship between this lack of secretory material and the induction of delayed implantation is suggested by the fact that mouse blastocysts enter a state of diapause in vitro when either whole serum or certain amino acids are omitted from the incubation medium (Gwatkin, 1966a, b;McLaren, 1973).…”

“…In the mouse (Yoshinaga & Adams, 1966) and rat (Canivenc & Laffargue, 1956;Yoshinaga, 1961;Psychoyos, 1973;Surani, 1975), however, these events require the presence of oestrogen as well as progesterone. It may be significant that the other two species for which an oestrogen requirement for implantation has been suggested, the roe deer (Aitken, 1974a(Aitken, , b, 1975 and fur seal (Daniel, 1974), also exhibit the phenomenon of delayed im¬ plantation.…”

Changes in progesterone concentrations in the Japanese long-fingered bat, Miniopterus schreibersii fuliginosus

“…armadillo (Labhsetwar & Enders, 1968;Peppier & Stone, 1976), stoat (Gulamhusein & Thawley, 1974), European badger (Bonnin et al, 1978), spotted skunk (Mead, 1981), northern fur seal (Daniel, 1981) and black bear (Foresman & Daniel, 1983), the corpora lutea are less active during embryonic diapause, and the plasma progesterone concentrations stay slightly above the values in non-pregnant animals until shortly before implantation, when the concentrations begin to increase with activation of the corpora lutea. However, the roe deer, Capreolus capreolus, is unique in having an active corpus luteum throughout the diapause period, although no significant change is detected in the progesterone concentration until after implantation (Hoffman et al, 1978;Aitken, 1981). A high progesterone concentration and the presence of active corpora lutea are important for maintenance of lactational delayed implantaton in the mouse and rat (Yoshinaga, 1974; Gidley- Baird, 1981).…”

Plasma progesterone levels during delayed implantation in the European badger (Meles meles)

“…Plasma progesterone levels also increase in the armadillo, Dasypus novemcinctus, at time of implantation (Peppier & Stone, 1976), but in roe deer, Capreolus capreolus concentrations of pro¬ gesterone during the preattachment phase of embryonic elongation (Aitken, 1974) are not signifi¬ cantly different from those during diapause. The administration of progesterone to intact or ovariectomized badgers during the delay phase does not terminate diapause (Canivenc & Laffargue, 1958) and the induction of implantation may involve more than a simple increase in ovarian pro¬ gesterone production.…”