Progesterone Levels During the Oestrous Cycle and Pregnancy in the Cuis, Galea Musteloides

Abstract

Summary. The progesterone levels in arterial plasma, luteal and non-luteal ovarian tissues of the cuis, Galea musteloides, were determined at various stages of the oestrous cycle and pregnancy, using gas\p=m-\liquid chromatography with electron-capture detection. Plasma progesterone levels (8 to 18 ng/ml) during the oestrous cycle are lower than those found in pregnancy where they stayed at 23 to 60 ng/ml during the first 15 days. They rose to 513 ng/ml at Day 26 and thereafter gradually declined to 108 ng/ml a few days before parturition (Day 53). Within 24 hr after parturition, the level dropped to 23 ng/ml. During pregnancy, the pattern of changes in plasma progesterone levels and even the absolute concentrations (except for the first 15 days) resembled those of the guinea-pig. Progesterone concentration and content in the luteal tissue differed from those of the latter species. The results indicated that the maximal activity of the CL occurred between 20 and 30 days' gestation, the timing of which was again similar to that in the gui nea\x=req-\ pig. By comparison with other species, it was obvious that during gestation, both the guinea-pig and the cuis had very high plasma progesterone concentrations, and that gestation in these two animals could be divided into two phases according to these levels. The primary phase was the first 15 days when plasma progesterone was relatively low and the secondary phase was the latter half of gestation when the plasma progesterone concentration was at least fifteen times that of the primary phase. In both species, the establishment of the allantochorionic placenta occurred at the transition between these two phases when the plasma progesterone concentration was rising rapidly. The two phases probably represented stages where the requirement and metabolism of progesterone was widely different.

Serological evaluation of ovarian steroids of red-rumped agouti (Dasyprocta leporina) during the estrous cycle phases

“…This value is different for a number of hystricomorphs species reported in the literature. P4 recorded in this investigation is higher than that reported for guinea-pigs (Cavia porcellus) (2·8 ± 0·33 ng/ml) (Challis et al, 1971), (3.66 ± 1.1 ng/ml) (Hossain et al, 1979); lower (18 ± 1.23 ng/ml) than reports on non-pregnant cuis (Galea musteloides) (Tam, 1973); porcupine (Hystrix africaeaustralis) (13.8 ± 2-8 ng/ml) (van Aarde and Potgieter, 1986) and similar to values for Cuniculus paca, (6.18 ± 3.70 ng/ml) (Pérez and Baz, 2001) and black-rumped agouti (D.prymnolpha) (3.71 ± 1.48 ng/ml) (Guimarães et al, 2011). In the absence of fertilization after ovulation, the cells of the follicle transform into fully functional luteal tissue, responsible for the elevated P4 values in the luteal phase.…”

Circulating progesterone, progesterone-binding proteins and oestradiol-17 concentrations in the pregnant Cape porcupine, Hystrix africaeaustralis

“…Gestation lengths in hystricomorphs vary considerably but are longer than those predicted for their body sizes (Weir, 1974). In the porcupine (gestation length [93][94] days) the initial period of pregnancy (0-25 days post coitum) is, as in the guinea-pig (Challis et al,191Ì), cuis, Galea musteloides (Tam, 1973), and coypu, Myocastor coypus (Rowlands & Heap, 1966), characterized by relatively low levels of circulating progesterone when compared to values during later stages of pregnancy. Progesterone values increased rapidly between Days 25 and 40 post coitum and attained maximum values 50-60 days after mating.…”

Reproduction in male Pipistrellus pipistrellus (Mammalia: Chiroptera)

“…), the amounts of testosterone and androstenedione (as testosterone monochloroacetate) were determined by gas-liquid chromatography (GLC) with electron capture detection. GLC technique was similar to that previously described (Tam, 1971;1973). The quantities of compounds in the radioactive internal standards were always subtracted from the results.…”