Open pulled straw vitrification of murine and caprine embryos and timed deep uterine insemination of goats

摘要: The thesis consists of two sections, the first which is comprised experiments involving open-pulled-straw (OPS) vitrification method for cryopreserving caprine and murine embryos.In experiment applicability OPS method, found to be effective in blastocysts (El-Gayar et al., 2001), other embryonal stages was investigated. Morphologically intact morulae, blastocysts, hatching hatched collected from superovulated does between day 6 9 after onset estrus, were vitrified by method. French mini-straws heat-softened, pulled cut at narrowest point get a modified straw with diameter approximately half original one. Embryos equilibrated medium 199 supplemented 20% goat serum, containing 10% ethylene glycol (EG) dimethyl sulfoxide (Me2SO), 39°C 1 min then EG Me2SO 20 seconds. embryos loaded into narrow end capillary force straws plunged directly liquid nitrogen. After step-wise thawing sucrose solution 39°C, transferred synchronized recipients (-24 h) endoscopic means. As control, conventional freezing (embryos M2 1.5 m EG, 0.25 ml cooled rate 0.5°C/min) employed. Of 11 receiving OPS-vitrified (82%) became pregnant all them kidded. corresponding values 50% 40% (4/10) kidding. Overall embryo survival amounted 70% (16/23) 42% (8/19) conventionally frozen embryos. only 3 (33%) 2 (22%) kidded, resulting an 13% (2/15). When similar pregnancy achieved 33% (3/9) goats went term, 19% (3/16). In case there no significant difference cryopreservation techniques (P 0.05). To contrary exerted Medium 0.8 M however, significantly inferior media 0.0 or 0.4 (40-54%, P<0.001). Hatching rates followed trend. At it 44-57% 29-42% 19-23. expansion rate; high concentration zero low (P<0.001). Only about that had reached expanded blastocyst stage continued hatching. groups, 45 47%, respectively, compared almost 60% group. It may concluded incorporation concentrations beneficial post-warming mouse blastocysts. Warming can performed single-step omitting dilution medium.The second section attempt apply technique fixed-time deep uterine insemination goats. Ovulation induction accomplished commonly used Gonadotropin Releasing Hormone (GnRH) human Chorionic (hCG). question whether hCG substituted GnRH as ovulation inducing agent prostaglandin F2α (PGF2α)-synchronized underlying intention reduce incidence short cycles providing more sustained stimulation corpus luteum (CL), conjecturing this will render CL less prone premature regression. Sixty pluriparous Boer randomly assigned treatment groups. All subjected i.m. injection 5 mg Dinoprost (Dinolytic®, Pfizer) during luteal phase estrous cycle. constituting control group inseminated 12-14 h detected estrus. another up, 48 hours later, (0.004 Buserelin, Receptal®, Intervet); remaining 500 I.U. (Chorulon®, Intervet). latter groups artificially 16 later. Ovarian activity monitored ultrasonography estrus detection performed, 8 intervals, aproned male. Artificial conducted described Sohnrey Holtz (2005). some goats, procedure slightly that, instead lifting up hind quarters animal order introduce catheter, stood restraining crate equipped hammock-like sling holes forelimbs (Suyadi 2000). prevented crouching moving while being inseminated. Three (15%) (10%) exhibited tail flagging only, all! others displayed standing There differences among gro ups regard time PGF2α (44.5, 46.6 41.6 controls, GnRH- respectively). Duration was, on average, 10 shorter than (37.1 versus 46.4 48.4 h, P<0.05). numbers virtually (2.5, 2.4 2.1). regression lower (5 vs. 40 35%, Pregnancy 60%, 35%. Corresponding kidding 60, disregarding regression, 63, 83 54% 67 54%. kids born control-, 1.83, 1.88 1.71, respectively. conclusion, synchronization accomplishable phase; terminated either hCG. hoped-for reduction using not achieved.