Adding chitosan nanoparticles of green tea extract in diluent and thawing temperatures ameliorate the post-thawed quality of Boer buck semen

Objective:To improve the quality of post-thawing Boer buck semen for artificial insemination by adding green tea extract chitosan nanoparticles to skimmed egg yolk diluent,and the proper thawing temperature.Methods:The ejaculate of Boer buck was added to skimmed egg yolk diluent without(the control group)and with adding 1μg of chitosan nanoparticles of green tea extract per mL of diluent(the treatment group).Then,the diluted semen was filled in French mini straws containing 60×106 live sperm per straw,frozen in a standard protocol,and stored as frozen semen at−196℃for a week.Six replicates from each group were diluted for 30 s at 37℃or 39℃sterile water to evaluate the semen quality.Results:Post-thawing(at 37℃or 39℃)of live sperm,progressive motility,and plasma membrane integrity were lower compared to those of the pre-freezing stage(P<0.05).Thawing at 37℃resulted in no significant difference in live sperm,progressive motility,and plasma membrane between the control group and the treatment group(P>0.05).The live sperm,progressive motility,and plasma membrane of the treatment group in the pre-freezing stage,and post-thawed at 39℃were higher compared to those of the control group(P<0.05).There was no significant difference in malondialdehyde(MDA)concentration,DNA fragmentation,and catalase concentration of thawing at 37℃compared to those of 39℃in the same group.The MDA concentration and DNA fragmentation in thawing at 37℃and 39℃of the treatment group were significantly lower than those of the control group(P<0.05).However,the catalase concentration in thawing at 37℃and 39℃of the treatment group was not significantly different than the control group(P>0.05).Conclusions:Higher quality post-thawing Boer buck semen is achieved by adding 1μg/mL of chitosan nanoparticles of green tea extract to the skimmed egg yolk diluent and thawing at 39℃.

Prolonged post-thaw culture of embryos does not improve outcomes of frozen human embryo transfer cycles: A prospective randomized study

Objective:To evaluate the impact of prolonged post-thaw embryos culture on pregnancy outcome during frozen embryo transfer cycles.Methods:This prospective cohort study evaluated 324 thaw transfer cycles with 819 embryos from 269 patients at the Center for Reproductive Endocrinology and Infertility of Hue University Hospital in Vietnam.These frozen embryo transfer cycles were divided into two groups at the time of thawing:the short culture group(2-hour post-thaw culture)and the overnight culture group(overnight culture for 18 h)before the embryo was transferred into the uterus.The rates of embryo intact,grade A embryo at frozen and transfer time and continuing cleavage were recorded.The clinical outcomes including serum beta-human chorionic gonadotropin,clinical pregnancy and implantation rate were evaluated after 14 days,4 weeks,6 weeks,respectively,after embryo transfer.Results:Human chorionic gonadotropin positive occurred in 39.5%of patients in the short culture group compared to 25.9%in the overnight culture group with risk difference(RD)=13.6%,relative risk(RR)=1.343,95%confidence interval(CI)1.085-1.663,P<0.01.Clinical pregnancy rate of the short culture group and overnight culture group was 33.3%and 24.1%,respectively(RD=9.2%,RR=1.242,95%CI 0.996-1.549,P=0.06)and the implantation rate in the short culture group and overnight culture group was 16.5%and 11.0%,respectively(RD=5.5%,RR=1.244,95%CI 1.046-1.479,P=0.01).In women of advanced age(≥35 years)and women who received 3 embryos,pregnancy outcomes were found to be significantly(P<0.05)higher in the short culture than in the overnight culture group.Conclusions:The prolonged post-thaw culture period does not increase pregnancy outcome in comparison with the short culture.

Methanolic pomegranate dried peel extract improves cryopreserved semen quality and antioxidant capacity of rams

Objective:To select the appropriate concentrations of methanolic pomegranate extract supplemented in rams’semen extender for obtaining the best-cryopreserved semen quality.Methods:Tris-based semen extender was supplemented with 0.0,0.40,0.48,and 0.56 mg/mL pomegranate peel methanolic extract to extend semen collected from five native rams twice weekly for two months(n=80).Pooled(n=16)post-thaw semen characteristics were determined.Thawed seminal plasma of all supplemented and control groups were used to measure malondialdehyde(MDA),nitric oxide(NO),glutathione peroxidase(GPx),superoxide dismutase(SOD),ascorbic acid,zinc,copper,total cholesterol,low-density lipoproteins(LDL),lactate dehydrogenase(LDH),and alkaline phosphatase(ALP).Results:The supplementation of Tris-based semen extender with 0.48 mg/mL semen extender resulted in the highest post-thaw sperm total motility(P<0.001),sperm progressive motility(P<0.001),live sperm(P<0.001),sperm plasma membrane integrity(P<0.001),acrosome integrity(P<0.001),SOD(P<0.05),zinc(P<0.001),total cholesterol(P<0.001),and LDL(P<0.001)with the lowest percentage of abnormal sperm morphology(P<0.001),the lowest lipid peroxidation(MDA,P<0.01),ascorbic acid(P>0.05),and LDH(P>0.05).Conclusions:Pomegranate peel methanolic extract 0.48 mg/mL supplemented to Tris-based semen extender of rams is the best enrichment in preserving the sperm post-thaw characteristics via improving biochemical profiles and antioxidant capacity.

Taurine in semen extender modulates post–thaw semen quality,sperm kinematics and oxidative stress status in mithun(Bos frontalis)spermatozoa

Objective:To assess the effect of taurine on post-thaw semen quality parameters,sperm kinematics,antioxidant and oxidative stress profiles and sperm cholesterol efflux in mithun(Bos frontalis).Methods:A total of 50 ejaculates(n=25 samples)were selected based on biophysical parameters.Each sample was split into four equal aliquots after dilution with the Tris-citrate-glycerol extender.GroupⅠ,Ⅱ,ⅢandⅣcontained 0 mM(the control),25 mM,50 mM and 100 mM of taurine,respectively.Frozen-thawed samples were analysed for motility parameters(progressive forward and in bovine cervical mucus penetration test),kinetic and velocity parameters by computer-assisted sperm analyzer,viability,sperm and nuclear abnormalities,acrosome integrity,plasma membrane and nuclear integrities,sperm enzymatic leakage and biochemical(sperm cholesterol and oxidative stress)profiles.Results:The extender containing 50 mM taurine led to a significant enhancement in viability,acrosomal integrity,plasma membrane integrity,motility(progressive and in cervical mucus),and sperm cholesterol content and notably reduced sperm morphological and nuclear abnormalities,and leakage of intracellular enzymes compared to other taurine treated and untreated control groups(P<0.05).Moreover,in addition to significant improvement in kinetic and velocity profiles,50 mM taurine protected the integrity of acrosome and biochemical membranes than in the untreated control and other taurine treated groups.Inclusion of 50 mM taurine held a clear advantage over the control or 25 mM or 100 mM taurine in cryopreservation of mithun semen.Conclusions:Taurine(50 mM)supplementation in semen extender can be effectively utilized to reduce oxidative stress and improve post-thaw semen quality in mithun.