Capacitation is a complex and not well-understood process that encompasses all the molecular changes sperm must undergo to successfully fertilize an oocyte. In vitro fertilization has remained elusive in horse, as evidenced by low (IVF) rates (0%-33%); moreover, only two foals have ever been produced using IVF. Incubation of stallion modified Whittens supplemented with bovine serum albumin sodium bicarbonate yielded significant time-dependent protein tyrosine phosphorylation induced...

The chromatin configuration of resting horse oocytes and the time course in vitro oocyte maturation was characterized using a fluorescent, DNA-specific label. Oocytes were classified as having either compact (CP) or expanded (EX) cumuli at collection. Centrifugation effective allowing visualization germinal vesicle. Two main configurations found known to have vesicle: condensed (CC), which formed dense mass surrounding nucleolus; fluorescing nucleus (FN), entire nucleus, containing diffuse...

We evaluated the relationship of initial chromatin configuration to time oocyte recovery and nuclear maturation after culture in horse oocytes having compact (Cp) expanded (Ex) cumuli. In addition, we effect type, recovery, duration on blastocyst development intracytoplasmic sperm injection. collected within 1 h slaughter, fibrillar intermediate configurations were more prevalent Cp than Ex (68% 12%, respectively). a 5- 9-h delay, proportions decreased significantly, degenerating...

Horse oocytes with expanded (EX) cumuli appear to have greater meiotic competence than do horse compact (CP) but are thought come from atretic follicles. We evaluated the relationships among cumulus expansion, follicle viability, initial chromatin configuration, and of oocytes. Follicle walls were sectioned for histological examination, follicles scraped obtain Half immediately half matured 24 h in vitro. Cumulus expansion was significantly associated atresia. Initially, more EX CP had...

Work with lyophilized sperm helps delineate the factors required for successful fertilization. We investigated use of in equine embryo production. In Experiment 1, DNA fragmentation index was not affected by three freeze/thaw or lyophilization cycles. 2, oocytes injected from a treatment which were suspended cytoplasmic extract (SE) yielded blastocyst development rates 0 and 28% respectively ( P <0.05). 3, rate 6–11% after injection fresh frozen–thawed semen, SE. 4, 3.5 months 1 week...

Intracytoplasmic sperm injection (ICSI) is used to produce foals from otherwise infertile mares and stallions with limited stores, but requires expensive equipment technically demanding. Methods transport oocytes ICSI laboratories would allow collection of by the referring veterinarian enable greater application this technique.This study was conducted evaluate protocols that could be immature maturing for ICSI.In vitro experiment.Oocytes were recovered transvaginal ultrasound-guided...

Abstract Methods for standard in vitro fertilization have been difficult to establish the horse. We evaluated whether prolonged sperm pre-incubation would support subsequent fertilization. Fresh were pre-incubated with penicillamine, hypotaurine, and epinephrine (PHE) 22 h. Co-incubation of cumulus-oocyte complexes (COCs) 6 h yielded 43% fertilization; culture presumptive embryos 21% blastocysts. Sperm incubated similarly, but without PHE, did not fertilize oocytes. Use extended semen system...

Horse oocytes were collected from an abattoir over a 15-mo period. After classification of follicle size and cumulus morphology, either fixed immediately (0 h) or matured in vitro (24 h). There was no effect season on the number antral follicles present ovaries, oocyte maturation rate for any class oocyte. The proportion having condensed chromatin at 0 h increased with increasing size. also size, </= 20-mm diameter, higher initially expanded cumuli than those compact cumuli. strongly...

This study was undertaken to evaluate the development of equine oocytes in vitro and vivo after intracytoplasmic sperm injection (ICSI) with either fresh or frozen-thawed spermatozoa, without use additional activation treatments. Oocytes were collected from ovaries obtained an abattoir classified as having expanded cumulus cells matured M199 10% fetal bovine serum 5 microU FSH ml(-1). After 24-26 h maturation, a first polar body selected for manipulation. Fresh ejaculated stallion...

Three experiments were conducted to evaluate the effect of oocyte and sperm treatments on rates in vitro fertilization (IVF) horse determine capacity vitro-matured oocytes be fertilized vivo. There was no duration maturation (24 vs. 42 h) or calcium ionophore concentration during capacitation (3 μM 7.14 μM) rates. Oocytes matured 100% follicular fluid had significantly higher (13% 24%) than did medium 20% (0% 12%; P < 0.05). significant difference rate among 3 utilizing (12% 21%). Of...

Summary Swab specimens for bacterial culture were obtained from the uterus, vagina, vestibule, and clitoral fossa of 48 mares that had normal reproductive tracts, no history problems, inflammation on evaluation endometrial biopsy. The predominantly Thoroughbred Standardbred. vagina through a sterile speculum; swab uterus by use double-guarded, occluded instrument. Fifteen (31%) uterine 20 (42%) vaginal yielded growth aerobic culture; however, only 2 (4%) 4 (8%) more than 10 colonies. In...

In vitro fertilization does not occur readily in the horse. This may be related to failure of equine sperm initiate hyperactivated motility, as treating with procaine induce hyperactivation increases rates. mice, motility requires a sperm-specific pH-gated calcium channel (CatSper); therefore, we investigated this sperm. Motility was assessed by computer-assisted analysis and changes intracellular pH were using fluorescent probes. Increasing induced rise calcium, which inhibited known...

Significance Nostoc symbioses with plants represent one of the most versatile and ancient types symbioses. The infection process is a tug-of-war between plant host cyanobacterial symbiont, reciprocal influence both partners on differentiation infectious motile filaments, hormogonia. In present study, we have uncovered major hormogonium-repressing factor punctiforme , nostopeptolide. To our knowledge, nonribosomal peptide first complex secondary metabolite cyanobacteria for which governing...

Protein tyrosine phosphorylation (PY) is a hallmark of sperm capacitation. In stallion sperm, calcium inhibits PY at pH <7.8, mediated by calmodulin. To explore the mechanism that inhibition, we incubated in media without added calcium, with or plus calmodulin inhibitor W-7 (Ca/W-7 treatment). Treatment inhibitors calcium/calmodulin-dependent kinases, protein kinase A (PRKA), Src family kinases suppressed induced absence but not Ca/W-7 treatment, indicating occurred via canonical PRKA...

Equine spermatozoa appear to differ from of other species in using oxidative phosphorylation preferentially over glycolysis. However, there is little information regarding effects different energy sources on measured parameters equine spermatozoa.

Abstract We recently reported successful equine IVF using fresh semen pre-incubated for a prolonged period (22 h) before co-culture with oocytes. In this study, we evaluated the feasibility of frozen–thawed sperm and capacitation-related changes in these over pre-incubation period. Sperm selected via commercial separation device (SSD) yielded significantly higher fertilization than did by swim-up or colloid centrifugation. Using SSD method, rates 15 min, 3 h, 6 9 h were 7.1, 22.2, 38.5,...

This study was conducted to evaluate in vivo and vitro development of vitro-matured equine oocytes fertilized by intracytoplasmic sperm injection. Oocytes were collected from slaughterhouse-derived ovaries, matured vitro, injected with frozen-thawed stallion sperm. In assessed after transfer the oviducts recipient mares. Mares killed 7.5-8.5 days uterus flushed for embryo recovery. Of 132 transferred, 69 (52%) recovered; these, 25 (36%) blastocysts a blastocoele capsule. three culture...