Differential gene-expression profiles from canine cumulus cells of ovulated versus in vitro-matured oocytes.

We compared the nuclear maturation status and gene-expression profiles of canine cumulus cells (CCs) derived from cumulus-oocyte complexes (COCs) that were spontaneously ovulated versus those that were matured in vitro. Cumulus-oocyte complexes were retrieved from uteri by surgical flushing (after spontaneous ovulation) or by ovariectomy follicle aspiration and in vitro maturation. The objective of Experiment 1 was to investigate the nuclear maturation status of in vivo- versus in vitro-matured oocytes. The objective of Experiment 2 was to compare gene-expression profiles of CCs derived from in vivo- versus in vitro-matured COCs. Genes analysed are related to cell maturation, development and apoptosis, including GDF9, MAPK1, PTX3, CX43, Bcl2 and BAX; mRNA expression for all of these genes, except for GDF9, differed (P<0.05) between in vivo- and in vitro-matured CCs. In conclusion, we found that gene-expression profiles are related to the quality of CCs and therefore posit that monitoring gene expression could be a useful strategy to guide attempts to improve in vitro culture systems.

Cell-free extract from porcine induced pluripotent stem cells can affect porcine somatic cell nuclear reprogramming.

Pretreatment of somatic cells with undifferentiated cell extracts, such as embryonic stem cells and mammalian oocytes, is an attractive alternative method for reprogramming control. The properties of induced pluripotent stem cells (iPSCs) are similar to those of embryonic stem cells; however, no studies have reported somatic cell nuclear reprogramming using iPSC extracts. Therefore, this study aimed to evaluate the effects of porcine iPSC extracts treatment on porcine ear fibroblasts and early development of porcine cloned embryos produced from porcine ear skin fibroblasts pretreated with the porcine iPSC extracts. The Chariot(TM) reagent system was used to deliver the iPSC extracts into cultured porcine ear skin fibroblasts. The iPSC extracts-treated cells (iPSC-treated cells) were cultured for 3 days and used for analyzing histone modification and somatic cell nuclear transfer. Compared to the results for nontreated cells, the trimethylation status of histone H3 lysine residue 9 (H3K9) in the iPSC-treated cells significantly decreased. The expression of Jmjd2b, the H3K9 trimethylation-specific demethylase gene, significantly increased in the iPSC-treated cells; conversely, the expression of the proapoptotic genes, Bax and p53, significantly decreased. When the iPSC-treated cells were transferred into enucleated porcine oocytes, no differences were observed in blastocyst development and total cell number in blastocysts compared with the results for control cells. However, H3K9 trimethylation of pronuclear-stage-cloned embryos significantly decreased in the iPSC-treated cells. Additionally, Bax and p53 gene expression in the blastocysts was significantly lower in iPSC-treated cells than in control cells. To our knowledge, this study is the first to show that an extracts of porcine iPSCs can affect histone modification and gene expression in porcine ear skin fibroblasts and cloned embryos.

No long-term feeding toxicities on the health status in rats fed with cloned Korean native beef cattle (Hanwoo) meat.

This study was designed to undertake a risk assessment to identify the health status of rats fed with somatic cell nuclear transfer (SCNT)-cloned Korean native beef cattle (Hanwoo) meat for 26 weeks. The rats were randomly divided into 5 groups, each consisting of 12 male (142.6 ± 5.23 g) and 12 female (113.7 ± 6.31 g) rats each. The animals were fed commercial pellets (control), pellets containing 5% (N-5) and 10% (N-10) of normal cattle meat, and diets containing 5% (C-5) and 10% (C-10) of cloned cattle meat. The mortality; clinical signs; body weight; food consumption; urinary, hematology, blood biochemistry, and histopathological analyses; and absolute and relative organ weights were analyzed and compared. During the 26-week test period, health status-related factors of the rats fed on cloned Hanwoo meat were found to have no test substance-related toxicities. The only difference was the increased uterus weight in female C-10 rats as compared to their counterparts counterparts (p < .05). On the basis of these health status results, it can be postulated that no food consumption risks might arise from the long-term feeding of cloned cattle meat in rats.

Quantitative analysis of sperm mRNA in the pig: relationship with early embryo development and capacitation.

Although it is well known that mRNA is present in mammalian spermatozoa, the relevance of mRNA to capacitation and early embryo development in the pig remains unclear. In the present study, we investigated differences in the abundance of selected mRNAs coding for MYC, CYP19, ADAM2, PRM1 and PRM2 in purified porcine spermatozoa depending on embryo cleavage rate and capacitation (n=20 semen samples). Semen samples were used in IVF procedures, with subsequent embryo development classified into one of two groups based on cleavage rate (i.e. high (>75%) and low (<75%) cleavage groups) and mRNA abundance in purified spermatozoa compared between these two groups. In addition, mRNA abundance was compared between capacitated and non-capacitated spermatozoa. Comparison of mRNA levels between porcine spermatozoa revealed that the abundance of MYC, CYP19, ADAM2, PRM1 and PRM2 mRNA was significantly greater in the high cleavage group (n=10 high cleavage group semen samples) than in the low cleavage group (n=10; P<0.05). Significant downregulation of MYC mRNA was observed in capacitated spermatozoa (n=12; P<0.05). The results of the present study suggest that the amount of specific mRNAs could be used for estimating the quality of spermatozoa in the pig.

Rho GTPase activating protein 15 (arhGAP15) siRNA effect apoptosis-induced by ethanol in bovine fibroblast cells.

The Rho GTPases are the sub-group of Ras super family and identified in all eukaryotes. The Rho GTPases effect different cellular signaling pathways involved in a number of diseases such as cancer, neurological and cardiovascular disorders. Members of Rho GTPases including RhoA, RhoC and Rac1 play a major role in regulation of apoptosis in different kind of stress conditions. Here we investigated the Rho GTPase activating protein 15 (ArhGAP15) gene knock-down effect on apoptosis induced by ethanol in bovine fibroblast cells. The bovine Fibroblast cells were treated and transfected with two different concentrations (50 and 100 nM) of ArhGAP15 siRNA for 48 h respectively. Both concentrations of siRNA were effective and the results of RT-PCR revealed an efficient knock-down of ArhGAP15 mRNA in fibroblast cells. Further, the normal cells exposed to a 100 mM ethanol concentration showed a reduction in cell viability and induced the ratio of apoptosis related Bax/Bcl-2 proteins compared with ArhGAP15 siRNA transfected ethanol treated cells. Ethanol also increased caspase-3 expression in normal fibroblast cells compared with transfected cells. The ArhGAP15 knock-down cells treated with ethanol decreased Bax/Bcl-2 ratio and lower caspase-3 protein levels in ArhGAP15 knocked-down cells. Our results suggest that apoptosis induced by ethanol involves the activation of Rho GTPase activating protein 15 and silencing of the said gene protects apoptosis.

Association of functional sequence variants of the myosin heavy chain 3 gene with muscle collagen content in pigs.

This study examined the association between functional sequence variants (FSVs) of myosin heavy chain 3 (MYH3) genotypes and collagen content in a Landrace and Jeju native pig (JNP) crossbred population. Four muscles (Musculus longissimus dorsi, Musculus semimembranosus, Musculus triceps brachii, and Musculus biceps femoris) were used for the analysis of meat collagen content, and the same animals were genotyped for the FSVs of the MYH3 gene by using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). Three FSVs of MYH3 genotypes were identified and had genotype frequencies of 0.358, 0.551, and 0.091 for QQ, Qq, and qq, respectively. QQ animals for the FSVs of the MYH3 genotypes showed higher collagen content in their M. longissimus dorsi (p < 0.001), M. semimembranosus (p < 0.001), M. triceps brachii (p < 0.001), and M. biceps femoris (p < 0.001) than qq homozygous animals. After the validation of this result in other independent populations, the FSVs of MYH3 genotypes can be a valuable genetic marker for improving collagen content in porcine muscles and can also be applied to increase the amount of collagen for biomedical purposes.

Identification of Copy Number Variations in Four Horse Breed Populations in South Korea.

In this study, genome-wide CNVs were identified using a total of 469 horses from four horse populations (Jeju horses, Thoroughbreds, Jeju riding horses, and Hanla horses). We detected a total of 843 CNVRs throughout all autosomes: 281, 30, 301, and 310 CNVRs for Jeju horses, Thoroughbreds, Jeju riding horses, and Hanla horses, respectively. Of the total CNVRs, copy number losses were found to be the most abundant (48.99%), while gains and mixed CNVRs accounted for 41.04% and 9.96% of the total CNVRs, respectively. The length of the CNVRs ranged from 0.39 kb to 2.8 Mb, while approximately 7.2% of the reference horse genome assembly was covered by the total CNVRs. By comparing the CNVRs among the populations, we found a significant portion of the CNVRs (30.13%) overlapped; the highest number of shared CNVRs was between Hanla horses and Jeju riding horses. When compared with the horse CNVRs of previous studies, 26.8% of CNVRs were found to be uniquely detected in this study. The CNVRs were not randomly distributed throughout the genome; in particular, the Equus caballus autosome (ECA) 7 comprised the largest proportion of its genome (16.3%), while ECA 24 comprised the smallest (0.7%). Furthermore, functional analysis was applied to CNVRs that overlapped with genes (genic-CNVRs); these overlapping areas may be potentially associated with the olfactory pathway and nervous system. A racing performance QTL was detected in a CNVR of Thoroughbreds, Jeju riding horses, and Hanla horses, and the CNVR value was mixed for three breeds.

Trichostatin A promotes the development of bovine somatic cell nuclear transfer embryos.

We studied the effects of trichostatin A (TSA), a histone deacetylase inhibitor, on the development of bovine somatic cell nuclear transfer (SCNT) embryos by investigating (1) the optimal concentration and treatment time of TSA for development of bovine SCNT embryos, (2) the status of histone acetylation in TSA-treated and control SCNT embryos and (3) the expression of histone acetylation- and deacetylation-related genes in TSA-treated and control SCNT embryos. We observed that 50 nM TSA-treatment for 20 h following fusion resulted in more efficient in vitro development of bovine SCNT embryos to the blastocyst stage. In regard to histone H4K5 acetylation, half of the control SCNT embryos faintly displayed histone H4K5 signals 30 min after electrofusion, while most of the TSA-treated SCNT embryos displayed histone H4K5 signals within 30 min after electrofusion. Furthermore, the expressions of HDAC1 and HDAC2 in the blastocysts were significantly lower (P<0.05) in the TSA-treated SCNT than in the control SCNT. However, the expression of GCN5 and HAT1 did not differ between the TSA-treated and control SCNT. In conclusion, we demonstrated that TSA-treatment after SCNT in bovine embryos can dramatically improve the practical applications of current cloning techniques.

3,4-Dihydroxyflavone acts as an antioxidant and antiapoptotic agent to support bovine embryo development in vitro.

The effects of two antioxidants, superoxide dismutase (SOD) and the flavonoid 3,4-dihydroxyflavone (DHF), on bovine embryo development in vitro were examined. Blastocyst development, total cell and inner cell mass (ICM) numbers, intracellular levels of reactive oxygen species (ROS), apoptotic indices and gene expression levels were examined before and after treatment of day 2 bovine embryos (≥2-4 cells) with various concentrations of 3,4-DHF or SOD for 6 days. Statistical analysis was performed using analysis of variance, with significance defined at the P<0.05 level. SOD had no significant effect on bovine embryo development at any tested concentration (control, 32.8%; 300 U/ml, 33.9%; 600 U/ml, 24.2%). In contrast, 10 µM 3,4-DHF promoted higher blastocyst development (39.3%) than any other concentration (control, 26.7%; 1 µM, 30.3%; 50 µM, 29.5%; 100 µM, 20.5%). Compared with 300 U/ml SOD, 10 µM 3,4-DHF resulted in significantly higher blastocyst development (44.2%) (control, 31.5%; SOD 300 U/ml, 33.6%). Treatment with 3,4-DHF increased the ICM cell number and reduced intracellular ROS production and apoptotic cell numbers. When O(2) tension was decreased from 20% (high tension) to 5% (low tension), embryo development rates were doubled regardless of 3,4-DHF treatment. Under high O(2) tension, 10 µM 3,4-DHF treatment may render bovine embryo development similar to a low O(2) tension environment. The best blastocyst development was obtained under low O(2) tension plus 10 µM 3,4-DHF treatment. The relative expression levels of antioxidant (MnSOD), antiapoptotic (Survivin, Bax inhibitor) and growth-related genes (IFN-τ, Glut-5) were significantly increased after 3,4-DHF treatment, while the expression levels of oxidant (Sox) and apoptotic genes (Caspase-3 and Bax) were reduced. These results suggest that 3,4-DHF may promote the in vitro development of bovine embryos through its antioxidant and antiapoptotic effects.

A diet of somatic cell nuclear transfer cloned-cattle meat produced no toxic effects on behavioral or reproductive characteristics of F1 rats derived from dams fed on cloned-cattle meat.

BACKGROUND: The composition and nutritional value of meat and milk derived from cloned animals and their progeny has not been demonstrated to be different from normal animals, but possible food consumption risks that might arise from unidentified hazards remain. In this study, we investigated the effects of somatic cell nuclear transfer cloned-cattle meat diet on the behavioral and reproductive characteristics of F1 rats derived from dams that were also fed on cloned-cattle meat. METHODS AND RESULTS: F1 rats were divided into five diet groups with their dams: commercial pellets (control), pellets containing 5% (N-5) and 10% (N-10) of normal-cattle meat, and diets containing 5% (C-5) and 10% (C-10) of cloned-cattle meat. In most cases, the cloned-cattle meat diet did not affect body weight and food consumption in both male and female F1 rats during 11 weeks, except for significantly higher body weight in both N-5 and N-10 (3-5 weeks, p<0.05 or p<0.01) and significantly higher food consumption in the both normal- and cloned-cattle meat groups (7-9 weeks, p<0.05 or p<0.01), as compared with the controls, respectively. We detected no signs of test substance-related toxicities on organ weights and behavioral characteristics (sensory reflex, motor function, and spatial learning and memory tests). Reproductive functions did not significantly differ among all examined rats (mating, fertility, and implantation). CONCLUSIONS: These behavioral and reproductive toxicity results suggest that there are no obvious food safety concerns related to cloned-cattle meat in these parameters.

GWAS and Post-GWAS High-Resolution Mapping Analyses Identify Strong Novel Candidate Genes Influencing the Fatty Acid Composition of the Longissimus dorsi Muscle in Pigs.

Fatty acid (FA) composition is one of the most important parameters for the assessment of meat quality in pigs. The FA composition in pork can also affect human health. Our aim was to identify quantitative trait loci (QTLs) and positional candidate genes affecting the FA profile of the longissimus dorsi muscle in a large F2 intercross between Landrace and Korean native pigs comprising 1105 F2 progeny by genome-wide association studies (GWAS) and post-GWAS high-resolution mapping analyses. We performed GWAS using the PorcineSNP60K BeadChip and a linear mixed model. Four genome-wide significant QTL regions in SSC8, SSC12, SSC14, and SSC16 were detected (p < 2.53 × 10-7). Several co-localizations of QTLs in SSC12 for oleic acid, linoleic acid, arachidonic acid, monounsaturated FAs, polyunsaturated FAs, and the polyunsaturated/saturated FA ratio were observed. To refine the QTL region in SSC12, a linkage and linkage disequilibrium analysis was applied and could narrow down the critical region to a 0.749 Mb region. Of the genes in this region, GAS7, MYH2, and MYH3 were identified as strong novel candidate genes based on further conditional association analyses. These findings provide a novel insight into the genetic basis of FA composition in pork and could contribute to the improvement of pork quality.

SINE indel polymorphism of AGL gene and association with growth and carcass traits in Landrace x Jeju Black pig F(2) population.

Genetic polymorphisms in the glycogen debrancher enzyme (AGL) gene were assessed with regard to their association with growth and carcass traits in the F(2) population crossbred Landrace and Jeju (Korea) Black pig. Three genotypes representing the insertion and/or deletion (indel) polymorphisms of short interspersed nuclear element were detected at frequencies of 0.278 (L/L), 0.479 (L/S), and 0.243 (S/S), respectively. The AGL S allele-containing pigs evidenced significantly heavier body weights at birth, the 3rd week, 10th week, and 20th week during developmental stages and higher average daily gains during the late period than were noted in the L/L homozygous pigs (P < 0.05), respectively. However, average daily gains during the early period were not significantly associated with genotype distribution (P > 0.05). With regard to the carcass traits, the S allele pigs (S/-) evidenced significantly heavier carcass weights and thicker backfat than was measured in L/L homozygous pigs (P < 0.05). However, body lengths, meat color, and marbling scores were all found not to be statistically significant (P > 0.05). Consequently, the faster growth rate during the late period and backfat deposition rather than intramuscular fat deposition cause differences in pig productivity according to genotypes of the AGL gene. These findings indicate that the AGL genotypes may prove to be useful genetic markers for the improvement of Jeju Black pig-related crossbreeding systems.

Length difference between equine ZFX and ZFY genes and its application for molecular sex determination.

PURPOSE: we analyzed the sex chromosome-encoding ZFX-ZFY genes and tested molecular sexing using the amplification patterns of intron 9 of ZFX-ZFY in the horse. METHODS AND RESULTS: the amplification of the ZFX-ZFY produced two distinct patterns, reflecting sexual dimorphism based on a length difference between the X and Y chromosomes. The amplification products from foals showed two distinct bands: one was common to all foals and mares, indicating that this band was amplified from ZFX, while the other was specific to some foals, indicating that it was from ZFY. The result based on the PCR assay was identical to the results of amplification of the Y chromosome-specific SRY gene and those of investigations of the phenotypic gender in three different horse populations. CONCLUSION: we suggest that this PCR strategy for determining sexes by comparing the amplification patterns of ZFX-ZFY genes is a convenient and precise method for discriminating sexes in horses.

Osmolarity at early culture stage affects development and expression of apoptosis related genes (Bax-alpha and Bcl-xl) in pre-implantation porcine NT embryos.

This study examined whether high osmolarity of culture medium at the early culture stage affects development and expression of apoptosis related genes (Bax-alpha and Bcl-xl) of porcine nuclear transfer (NT) and in vitro fertilization (IVF) embryos. NT and IVF embryos were divided into three groups and the basic medium was PZM-3 (260-270 mOsmol, control group). The control group of embryos was cultured in PZM-3 for whole culture period. Other two groups of embryos were cultured in a modified PZM-3 with 0.05 M sucrose (300-320 mOsmol, sucrose group) or increased NaCl to 138 mM (300-320 mOsmol, NaCl group) for the first 2 days, and then cultured in PZM-3 for 4 days. NT embryos cultured in NaCl group showed a significantly higher developmental rate to the blastocyst stage with a decreased apoptosis rate compared to the control (P < 0.05). There was no difference in blastocyst formation and apoptosis incidence among the three culture treatments for IVF-derived embryos. Bax-alpha mRNA expression was significantly higher in the control than sucrose or NaCl group for both NT and IVF embryos (P < 0.05). Moreover, the relative abundance of Bax-alpha/Bcl-xl was higher in the control than the treatment groups. These results indicate that the higher osmolarity at the early embryonic stage of porcine NT and IVF embryos can improve the in vitro development with reduced apoptosis through regulating the Bax-alpha/Bcl-xl gene expression.

Development of vitrified-thawed bovine oocytes after in vitro fertilization and somatic cell nuclear transfer.

Cryopreservation could be a useful technique for providing a steady source of oocytes for nuclear transfer and in vitro embryo production. The purpose of this study was to develop a method for cryopreservation of bovine oocytes while maintaining the developmental potential following subsequent in vitro fertilization (IVF) or somatic cell nuclear transfer (SCNT). Following vitrification-thawing, the surviving oocytes were (a) used for parthenogenetic activation, (b) examined for pronuclear formation after IVF, (c) examined for embryo development after IVF, and (d) used for SCNT employing fetal fibroblasts transfected with green fluorescent protein (GFP) gene. While most of the oocytes survived vitrification when the microdrop method was used (92.50%), the cleavage and blastocyst formation rates after parthenogenetic activation were lower (46.5% and 11.1%) than that in the non-vitrified control (86.6% and 13.5%). After IVF, the pronuclear formation (2PN) of fertilized embryos was lower in the vitrified group than in the control (21.7% and 59.9%). After SCNT, fusion rates were similar in control (58.33%) and vitrified-thawed oocytes (53.19%). However, the cleavage (73.1% and 46.3%) and blastocyst formation rates (22.2%, 7.4%; p<0.05) differed between control and vitrified-thawed oocytes. In vitrified-thawed or control oocytes, all embryos reconstructed using fetal fibroblasts transfected with GFP gene showed GFP expression. To evaluate the complete developmental potential, embryos derived from vitrified-thawed and fresh control oocytes were non-surgically transferred to 27 recipients (16 for control and 11 for vitrified-thawed). In the vitrified-thawed group, two pregnancies were detected at day 60, and one of them lasted until day 222. While in the fresh group, one pregnancy maintained to term. In conclusion, vitrified-thawed bovine oocytes could support development into the subsequent stages after IVF and SCNT. In addition, this study showed the possibility of the vitrified-thawed bovine oocytes in the production of transgenic cloned animals. In addition, further studies are required to increase the efficiency of oocyte vitrification for the practical uses and production of live offspring.

Genome-wide analyses of the Jeju, Thoroughbred, and Jeju crossbred horse populations using the high density SNP array.

The Jeju horse is an indigenous Korean horse breed that is currently registered with the Food and Agriculture Organization of the United Nations. However, there is severe lack of genomic studies on Jeju horse. This study was conducted to investigate genetic characteristics of horses including Jeju horse, Thoroughbred and Jeju crossbred (Jeju × Thoroughbred) populations. We compared the genomes of three horse populations using the Equine SNP70 Beadchip array. Short-range Linkage disequilibrium was the highest in Thoroughbred, whereas r2 values were lowest in Jeju horse. Expected heterozygosity was the highest in Jeju crossbred (0.351), followed by the Thoroughbred (0.337) and Jeju horse (0.311). The level of inbreeding was slightly higher in Thoroughbred (- 0.009) than in Jeju crossbred (- 0.035) and Jeju horse (- 0.038). FST value was the highest between Jeju horse and Thoroughbred (0.113), whereas Jeju crossbred and Thoroughbred showed the lowest value (0.031). The genetic relationship was further assessed by principal component analysis, suggesting that Jeju crossbred is more genetically similar to Thoroughbred than Jeju horse population. Additionally, we detected potential selection signatures, for example, in loci located on LCORL/NCAPG and PROP1 genes that are known to influence body. Genome-wide analyses of the three horse populations showed that all the breeds had somewhat a low level of inbreeding within each population. In the population structure analysis, we found that Jeju crossbred was genetically closer to Thoroughbred than Jeju horse. Furthermore, we identified several signatures of selection which might be associated with traits of interest. To our current knowledge, this study is the first genomic research, analyzing genetic relationships of Jeju horse, Thoroughbred and Jeju crossbred.

Wee1B depletion promotes nuclear maturation of canine oocytes.

Most mammalian oocytes are arrested at the germinal vesicle stage by activation of Wee1B. Meiotic resumption is regulated by inactivation of Wee1B and activation of cell division cycle 25B. The aim of this study was to determine whether treatment with Wee1B-targeting small interfering RNA (Wee1B-siRNA) promotes nuclear maturation of canine oocytes from germinal vesicle stage to metaphase II (MII) stage. In experiment 1, the percentage of canine oocytes that matured to MII stage was higher (P < 0.05) among oocytes cultured in vitro for 72 hours than among those cultured for 24 and 48 hours (5.4 ± 2.5% vs. 0.0 ± 0.0% and 1.4 ± 1.0%, respectively). Furthermore, the percentage of oocytes that matured to metaphase I (MI) stage was higher (P < 0.05) among oocytes cultured for 48 and 72 hours than among those cultured for 24 hours (14.9 ± 10.0% and 22.4 ± 8.1%, respectively, vs. 5.7 ± 6.0%). In experiment 2, canine oocytes were intracytoplasmically microinjected with Wee1B-siRNA (50 µM) at various culture time points (0, 24, 48, or 72 hours). The nuclear configuration of the exception of oocytes in the 72-hour group was examined after 84 hours of culture. The percentage of oocytes that matured to the MII stage was higher (P < 0.05) among those treated with Wee1B-siRNA at 0 hours than among control oocytes and those injected at 72 hours (18.0 ± 1.7% vs. 2.1 ± 2.8% and 0.0 ± 0.0%, respectively). Moreover, the percentage of oocytes that matured to the MI stage was higher (P < 0.05) among those injected at 0 hours than among control oocytes and those injected at 24 and 72 hours (45.9 ± 6.8% vs. 22.1 ± 3.5%, 22.8 ± 10.0%, and 10.0 ± 4.4%, respectively). In experiment 3, oocytes were intracytoplasmically microinjected with Wee1B-siRNA at 0 hours of IVM and cultured for 0, 24, 48, or 72 hours. Thereafter, maturation-related gene expression was analyzed by quantitative real-time polymerase chain reaction. Messenger RNA expression of cAMP and cell division cycle 25B was lower (P < 0.05) in oocytes injected at 48 hours than in the other groups. Messenger RNA expression of cAMP was lower (P < 0.05) in oocytes injected at 0 hours than in control oocytes and those injected at 72 hours. Messenger RNA expression of mitogen-activated protein kinase 1 and mitogen-activated protein kinase 3 was higher (P < 0.05) in oocytes injected at 72 hours than in the other groups. In conclusion, we confirmed that Wee1B-siRNA microinjection enhances the percentages of canine oocytes that reach the MI and MII stages. These data suggest that Wee1B-siRNA microinjection could be a useful strategy to obtain mature canine oocytes for research and assisted canine reproduction.

Effect of feeding fermented rice punch on oestrous induction in anoestrous bitches.

INTRODUCTION: As a consequence of poor productivity caused by a long anoestrous period, considerable research effort has been given to oestrus induction in dogs to enhance the productivity of young dogs and to preserve breeds. MATERIALS AND METHODS: Oestrus was induced in 30 anoestrous bitches more than three months after the last oestrus. Bitches orally received fermented rice punch with or without bromocriptine once daily for 21 consecutive days. The bitches were divided into two groups (n=10 per group): Group (1) fed fermented rice punch and Group (2) administered bromocriptine (100 µg/kg/day) and fed fermented rice punch. RESULTS: The concentration of dopamine in fermented rice punch was 47.2 mg/kg (parts per million). Six of 10 (60.0 per cent) and seven of 10 (70.0 per cent) bitches showed pro-oestrual bleeding in Groups 1 and 2, respectively. The mean and median values (min-max) to oestrus induction was not significantly different between Groups 1 and 2 (9.7±7.3, 6.5 (3-22) and 11.3±6.6, 7.9 (5-21) days) after treatment commencement (P>0.05). The pregnancy rate was very similar between Groups 1, 2 (66.0%) and control (66.0, 57.0 and 50.0 per cent). The mean and median values (min-max) of pups per bitch are also not significantly different between Groups 1, 2 and control (7.0±1.8, 7.0 (5-9) and 7.5±2.1, 7.5 (5-10) and 7.0±0, 7.0 (7-7)). CONCLUSION: We suggest that rice punch effectively induces oestrus in bitches.

In vitro development of canine somatic cell nuclear transfer embryos in different culture media.

The objective of the present study was to investigate the effects of three different culture media on the development of canine somatic cell nuclear transfer (SCNT) embryos. Canine cloned embryos were cultured in modified synthetic oviductal fluid (mSOF), porcine zygote medium-3 (PZM-3), or G1/G2 sequential media. Our results showed that the G1/G2 media yielded significantly higher morula and blastocyst development in canine SCNT embryos (26.1% and 7.8%, respectively) compared to PZM-3 (8.5% and 0%or mSOF (2.3% and 0%) media. In conclusion, this study suggests that blastocysts can be produced more efficiently using G1/G2 media to culture canine SCNT embryos.