Studies on growth of the mink blastocyst (original) (raw)
Related papers
Reproduction, 1987
In Exp. 1, administration of 5 mg oestradiol valerate i.m. to pregnant gilts on Days 9 or 9 and 10 advanced the uterine secretion of calcium, protein, and acid phosphatase as demonstrated by levels recovered in the uterine flushings of females unilaterally hysterectomized on Day 11. Upon removal of the remaining uterine horn on Day 12, protein and acid phosphatase increased while Ca2+ decreased in oestradiol\x=req-\ treated gilts as did PGF. In contrast, a 4-fold increase in recoverable Ca2+ occurred from Days 11 to 12 in control gilts. Recoverable oestradiol-17\g=b\ was increased in all 3 groups on Day 12 and plasmin inhibitor concentration increased in oestradiol-treated gilts. Two-dimensional PAGE demonstrated the appearance of a group of very acidic polypeptides in oestradiol-treated gilts. Blastocysts recovered from the second uterine horn had undergone elongation to the filamentous morphology in all 3 groups.
Luteotrophic effect of the rabbit blastocyst
Reproduction, 1978
Progesterone concentrations in peripheral plasma of 27 rabbits were determined by radioimmunoassay daily from Days 1 to 7. The rate of increase was significantly higher in pregnant than in pseudopregnant rabbits from Days 5 to 7 (P < 0\m=.\02), but not before Day 5. Transfer of Day-4 or -5 blastocysts to synchronous, pseudopregnant recipients resulted in a significant rise in progesterone levels in comparison with those in sham-operated controls (P < 0\m=.\01) or pseudopregnant does (P < 0\m=.\01).
Development of pig blastocysts in a uterine environment advanced by exogenous oestrogen
Reproduction, 1987
Routine embryo transfer techniques were used to establish recipient groups in which blastocysts were either asynchronous (blastocysts 24 h behind recipient uterus) or synchronous with their uterine environment. Oestradiol valerate (5 mg) was administered on Day 11 of the recipient's cycle to stimulate release of uterine secretion in the synchronous gilts (Group SE) and one group (AE) of asynchronous gilts. The gilts in the other asynchronous group (Group AC) were injected with vehicle (sesame oil). Embryos recovered on Day 14 by hysterectomy and flushing were evaluated for morphological development.
Biology of Reproduction, 1989
OviducwJfluid (OVF) was harvested chronicailyfrom 5 sows beginning on Day 1 of the estrous cycle (Day 0 of estrou.s cycle = day of detected estrus) and used for embryo culture (Day 3 OVF only). Two experiments were conducted to investigate in vitro development oil-cell and 2-cell porcine embryos in a modified Kreb's Ringer bicarbonate medium (culture medium, CM), early lueal phase OVF or CM supplemented with OVF (CM-OVF, 25% OVF v/v in CM) with or without transfer to fresh CM. In Experiment 1, 1-cell and 2-cell embryos were harvested from sows (n=7) approximately 44 h after detected estrus. In Experiment 2, 1-cell embryos were coil ected from 5 sows treated with altrenogest and gonadotropins, approximately 50 h after injection of human chorionic gonadotropin. The volume of OVF (ml) declined progressively throughout the 4
Biology of Reproduction, 1995
Mink endometrial cell lines were established by stable transfection of a plasmid vector encoding the SV40 large T antigen driven by the human p-actin promoter. A second plasmid vector, pSV2neo, was employed for selection of transfected cells. Specificity and homogeneity of consequent cell lines were evaluated by immunocytochemistryemploying antibodies against cytokeratin, desmin, and vimentin. Cytokeratin was found exclusively in epithelial cells, whereas vimentin appeared primarily in stromal cells. Neither cell line showed detectable desmin activity. These cell lines along with Buffalo rat liver (BRL) cells were employed in coculture with mink embryos in obligate diapause. Mink stromal and BRL cell lines were most effective in enhancing embryo survival in vitro. The percentages of cocultured embryos that survived for 72 h or more were 65% with epithelial cells, 75% with stromal cells, 68% with the combination of stromal and epithelial cells, and 93% with BRL cells. Only 23% of the embryos cultured without cells survived beyond 48 h. Embryo growth was also observed; some embryos in coculture showed trophoblastic outgrowth and adhesion to the cell surfaces. These results demonstrate that mink embryos in obligate delay can survive and develop in culture and that coculture with uterine or BRL cells increases the length and frequency of survival.
EFFECT OF BREED AND REPEATED SURGICAL COLLECTION ON RECOVERY RATE AND QUALITY OF RABBITS' EMBRYOS
Total of six New Zealand white (NZW) and similar number of Baladi Black (BB) rabbit does of 6-7 mo of age and 3.25-3.50 kg live body weight (LBW) were used as embryo donors to study the effect of breed and repeated surgical collection (three times) on quality and recovery rate of embryos. Ovulation was induced by administration of 20 mg GnRH i.m. at mating. Embryos were surgically collected 72 h post-mating by ventral midline laparotomy. After each collection process, the number of corpora lutea (CLs), normal (NF) and hemorrhagic (HF) follicles on each ovary and the number of recovered viable (VE) and unviable (UVE) embryos were recorded. In addition, ovulation rate (OR) and embryo recovery rate (ERR) were calculated. Results showed that number/doe of NF (23.8±1.55 vs. 16.6±1.31), HF (6.6±0.85 vs. 4.2±0.72) and total follicles (TF, 30.4±1.27 vs. 20.8±0.94) was higher (P<0.05) and OR was lower (28.3±0.89 vs. 42.8±0.71%, P<0.05) in Baladi than in MZW does. Number of CLs was 8.9 and 8.6/doe in NZW and Baladi rabbits, respectively. Thickness of mucin coat and diameter of mass cells and total diameter of embryos were significantly (P>0.001) higher in BB than NZW does. Average number of NF, HF and TF per doe was not affected by collection order. Meanwhile, number of CLs and OR increased (P<0.05) by increasing collection order, being 7.6±0.63 and 27.1±0.94% for the 1 st vs. 10.0±0.67 and 41.3±0.87% for the 3 rd collection, respectively. There were marked differences (P<0.05) on thickness of mucin coat and zona pellucid and diameter of mass cells of embryos with repeated collection. However, total diameter of embryos did not differ significantly.
Some characteristics of an inhibitor of embryonic development from rabbit oviductal fluid
Biology of reproduction, 1980
The oviductal fluid was obtained according to the intraabdominal flask technique of Uamner and Wilhams (1965). The fluids were aspirated daily using a sterile syringe and were frozen until used for embryo culture. The does used for fluid collection were ovariectomized at the time of the surgery for placement of the collecting flask. After a recovery period of 3 weeks, hormone replacement was begun. Estra diol-17@, 1 pg/kg/day, was injected s.c. for 6 days. After 3 days of withdrawal, progesterone, 1 mg/kg/ day, was injected for 5 days. Following another 2 day