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Oocyte Quality (oocyte + quality)
Selected AbstractsEFFECT OF ARTIFICIAL FEEDING ON DIGESTIVE EFFICIENCY, GROWTH AND QUALITIES OF MUSCLE AND OOCYTE OF MATURING ATLANTIC MACKEREL (SCOMBER SCOMBRUS L.)JOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2007KRISNA RUNGRUANGSAK-TORRISSEN ABSTRACT Maturing Atlantic mackerel with and without artificial feeding, kept in sea pens (September to May), showed differences in digestive efficiency (protease activity ratio of trypsin to chymotrypsin), muscle growth (concentrations of RNA, protein, RNA/protein ratio and free amino acids [FAA]) and oocyte quality (trypsin-like specific activity, and concentrations of RNA, RNA/protein ratio and FAA). The artificially fed mackerel had higher body weights (1.7 times) but with less white muscle protein concentration (0.5 time), compared to the control group. Both groups showed higher levels of capacity for protein synthesis in the oocytes than in the white muscle, but it was about two times higher in the artificially fed fish whereas about four times higher in the control group. This indicated that, during maturation, development of oocytes and muscle for growth occurred concurrently in higher growth mackerel, while development of oocytes dominated in slower growth fish. A higher trypsin-like specific activity with higher FAA levels in the oocytes from females fed with an artificial diet, compared to the control group, suggested differences in development and quality between the gametes of the fish with different feedings. PRACTICAL APPLICATIONS The work illustrates differences in digestive efficiency and the quality of growth performance (growth and protein metabolism in muscle and oocytes) in fish with different feedings. The use of various methods for evaluating digestive efficiency and the quality of fish growth performance could provide reasonable information for some important biological differences between fish groups, especially when the number of samples are low. It is more advantageous to apply different methods simultaneously than using growth parameter alone in order to study for precise evaluation of the quality of fish growth performance. The methods are very practical for studying food utilization and growth quality of fish in different environmental conditions and with different behaviors in aquaculture as well as in natural ecosystem where food consumption rate and feeding regime cannot be under control. [source] Estrogen administration during superovulation increases oocyte quality and expressions of vascular endothelial growth factor and nitric oxide synthase in the ovaryJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 4 2010Choong-Sik Ha Abstract Aims:, This study investigated whether estrogen administration during superovulation enhances oocyte quality using a mice model. We also investigated whether this estrogen treatment regulates the expressions of angiogenic factors, such as vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS), in the ovary. Method:, Female mice were co-injected with various doses of estrogen (1 µM, 10 µM and 100 µM) and pregnant mare serum gonadotrophin during superovulation, followed by human chorionic gonadotrophin injection 48 hours later. Then they were mated with individual males. After 18 hours, zygotes were flushed and cultured to blastocyst. The expression of VEGF and eNOS in the ovary was examined using Western blot and immunohistochemistry. The control group was superovulated without estrogen. Results:, Both numbers of ovulated zygotes and the rate of embryo development to blastocyst were significantly increased in the 1-µM estrogen dose compared to the control group. VEGF and eNOS expressions were stimulated by estrogen treatment. In particular, VEGF expression was significantly increased at 1-µM estrogen concentration, whereas, eNOS expression was significantly increased in all estrogen concentrations compared to controls. Conclusions:, The study showed that estrogen co-injection during superovulation increased the ovarian response, embryo developmental competence and expressions of VEGF and eNOS in the ovary. [source] Procedure for Maximizing Oocyte Harvest for In Vitro Embryo Production in Small RuminantsREPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2007A Gibbons Contents Possible effects of repeated hormonal treatments and laparoscopic ovum pick-up (LOPU) on the efficiency of oocyte recovery rate and quality were determined in sheep and goats. In six adult Merino sheep and five Criolla goats, ovarian status was synchronized by a prostaglandin F2, analogue and the insertion of an intravaginal sponge 48 h later. Follicle development was stimulated by a single dose of FSH (60 mg NIH-FSH-P1) plus a single dose of equine chorionic gonadotrophin (eCG; 300 UI). The first FSH/eCG doses were administered 48 h after the sponge insertion, being repeated every 4 days to complete a total of four treatments in sheep and three in goats. Follicles in both ovaries were categorized according to their diameter and follicular fluid was aspirated under laparoscopic observation without a vacuum pump. In sheep, during a 12-day-period, a total of 347 follicles were aspirated with a recovery rate of 46.9%. In goats, during an 8-day-period, 219 follicles were aspirated with a recovery rate of 45.6%. In both species, there were no significant differences in the number of aspirated follicles, oocyte recovery rate and good quality oocyte recovery rate. However, in sheep the oocyte recovery rate was higher for large follicles, whereas in goats no such effect was detected. In summary, current results indicate that retrieval of oocytes can be maximized, without affecting oocyte quality, by repeating ,oneshot' FSH/eCG regimes and LOPUs at intervals as short as 4 days. [source] Age, FSH Dose and Follicular Aspiration Frequency Affect Oocyte Yield from Juvenile Donor LambsREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2007I Valasi Contents Experiments were conducted to determine the effects of lamb age, frequency of follicular aspirations, and hormone stimulation by fixed or variable FSH dose, on the number of collected oocytes and their maturational competence. In trial 1, the characteristics of follicular population (number and diameter of follicles) were studied in 40 lambs which were slaughtered at the age of 30 days (S1), 42 days (S2), 60 days (S3) and 5,6 months (S4), each n = 10. In trial 2, 27 lambs were divided into four groups. group MF lambs (n = 6) had follicular aspiration (OPU) in four monthly intervals commencing from the age of 8,9 weeks (sessions MF1, MF2, MF3 and MF4). In groups SF2, SF3 and SF4 (each n = 6), OPU was conducted once during the 12,13, 16,17 and 20,21 week of age, respectively. Ovarian stimulation was conducted with fixed FSH dose (3.52 mg/animal). In trial 3, 10 lambs (group MV) were treated as those of group MF apart from the FSH dose, which was administered according to the body weight in a dose of 0.27 mg/kg. The number and the size of follicles, the number and the quality of collected oocytes and the maturational competence of the oocytes were compared between and within groups. In trial 1, the total number and the number of small follicles were greater in groups S1 and S2 compared with those of S3 and S4 (p < 0.01). Similarly, the follicular population was greater in group MF1 than in group SF3 (p < 0.01). In sessions MF2, MF3, MV2, MV3 and MV4, more oocytes were collected in comparison with those from the respective once-aspirated age mates (groups SF2, SF3 and SF4). In total, more (p = 0.02) oocytes per donor were collected from group MV (15.2 ± 5.5) than from group MF (9.0 ± 3.2). An absolute maturational failure was observed in oocytes collected from groups SF2 and SF3. Maturational competence varied between 16.7% and 58.3% (p = 0.017) among sessions of group MF, but it was more uniform among sessions of group MV (range 12.5,42.9%, p > 0.05). Our results indicate that firstly, the number and the quality of harvested oocytes from juvenile lambs can be much improved if follicular stimulation regime is adjusted to the body weight. Secondly, in terms of follicular population and oocyte quality, 3 and 4-month-old lambs are naturally bad oocyte donors, but this characteristic can be reversed by a previous follicular ablation. [source] Cumulus,Oocyte Communications in the Horse: Role of the Breeding Season and of the Maturation MediumREPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2004S Colleoni Contents Horse is a seasonal breeder and information on oocyte quality outside the breeding season is very limited. Ovaries obtained at the slaughterhouse are a convenient but often limited source of oocytes in this species. As the low quantity of ovaries leads to an intensive use of all available material, it would be useful to know whether ovaries collected during the non-breeding season are suitable for in vitro maturation (IVM). In an attempt to characterize the effect of season on oocyte quality, we investigated the permeability of the gap junctions (GJ) present between cumulus cells and oocytes because of their important role in oocyte growth and maturation. We also compared the effect of supplementing the maturation medium with bovine serum albumin (BSA) or oestrus mare serum (EMS). A total of 645 oocytes isolated from 158 and 154 ovaries collected during the breeding and the non-breeding season, respectively, were used in this study. Oocytes were matured for 30 h in TCM 199 supplemented either with 10% EMS or with 4 mg/ml BSA. The presence of permeable GJs between cumulus cells and oocytes was investigated with the injection of a 3% solution of the fluorescent dye Lucifer yellow into the ooplasm. No differences in efficiency of oocyte retrieval or oocyte meiotic competence were detected between oocytes collected during the breeding and non-breeding season. The vast majority (90%) of the oocytes collected during the breeding season had fully functional communications with their surrounding cumulus cells but such communications were completely interrupted in 55.3% of the oocytes collected during the non-breeding season. During the non-breeding season, the proportion of oocytes whose communications with cumulus cells were classified as closed or intermediate at the end of maturation was lower in the group matured with BSA than with EMS (71.4 vs 97.7, p < 0.05). The same trend, although not statistically significant, was observed during the breeding season also. The presence of BSA caused an incomplete cumulus expansion during both seasons. Our data indicate that oocytes collected during the non-breeding season do not show any meiotic deficiency but lack active communication with the surrounding cumulus cells at the time of their isolation from the ovary. No data are available at present for determining the consequences on the developmental competence even if data from other species suggest that this is likely. [source] | ||||||||||