Mesenchymal stem cells (MSCs) have been widely used as donor cells for somatic cell nuclear transfer (SCNT) to increase the efficiency of embryo cloning. Since replicative senescence reduces the efficiency of embryo cloning in MSCs during in vitro expansion, transfection of telomerase reverse transcriptase (TERT) into MSCs has been used to suppress the replicative senescence. Here, TERT-transfected MSCs in comparison with early passage MSCs (eMSCs) and sham-transfected MSCs (sMSCs) were used to evaluate the effects of embryo cloning with SCNT in a porcine model. Cloned embryos from tMSC, eMSC, and sMSC groups were indistinguishable in their fusion rate, cleavage rate, total cell number, and gene expression levels of OCT4, SOX2 and NANOG during the blastocyst stage. The blastocyst formation rates of tMSC and sMSC groups were comparable but significantly lower than that of the eMSC group (p < 0.05). In contrast, tMSC and eMSC groups demonstrated significantly reduced apoptotic incidence (p < 0.05), and decreased BAX but increased BCL2 expression in the blastocyst stage compared to the sMSC group (p < 0.05). Therefore, MSCs transfected with telomerase reverse transcriptase do not affect the overall development of the cloned embryos in porcine SCNT, but enables to maintain embryo quality, similar to apoptotic events in SCNT embryos typically achieved by an early passage MSC. This finding offers a bioengineering strategy in improving the porcine cloned embryo quality.
Karyotype analysis is a major work in the process of triploid abalone production for the purpose of productivity and quality improvement. However, the metaphase spreads for karyotype analysis have been prepared just from the larvae at trochophore stage, which has restricted the spectrum of sample correction inhibiting more efficient analysis. Here, we investigated the feasibility of preparing metaphase spreads from the larvae at veliger stage that is the next developmental stage of trochophore. For this, diploid and triploid larvae at trochophore and veliger stages from Pacific abalone (Haliotis discus hannai ) were subjected to metaphase spread preparation and its efficiencies were measured and compared each other. As the results, although the efficiencies of metaphase spread preparation were significantly lower in the larvae at veliger stage compared to the ones at trochophore stage regardless of ploidy status, we found that the preparation of metaphase spreads, which showed the clear chromosomal images containing the normal number of chromosomes, was possible from the veliger stage larvae. On the other hands, all larvae used in this study regardless of developmental stage and ploidy did not show colchicine sensitivity. Moreover, no significant difference was observed in cell cycle distribution of the cells comprising larvae between two developmental stages regardless of ploidy status. These suggested that the details of protocol to prepare metaphase spreads from abalone larvae should be optimized depending on its developmental stages. Taken together, we demonstrated the feasibility of preparing metaphase spreads from H. discus hannai veliger stage larvae for karyotype analysis.
This study used adult wistar-based rats to observe the sexual cycle as a morphological characteristic of vaginal epithelial cells by vaginal smearing, and investigated the fetal number through mating with male rats of the same strain. The target animal was a 12 to 13-week-old Wistar-based mature unlighted rat (weight 220 g to 240 g), room temperature 23 ± 2℃, 14 hours artificial lighting (05:00 to 19:00 hours), 10 hours Adapted individuals were used for rearing for at least 2 weeks under the conditions of the darkroom (19:00 to 05:00). The feed was managed for free feeding of pellet feed for animals and water. The vaginal smearing method was used for the experiments by observing the sexual cycle every morning and confirming that the normal sexual cycle of 4 or 5 days was repeated at least 2 cycles or more. As a result, the proestrus was found to have few red blood cells, the cells and nuclei were rather large and round, and many nucleated cells were identified. In the case of the estrus, the cells were large and the nuclei were not stained, and most of the keratinocytes were found. In addition, in the metestrus and diestrus, there were many white blood cells, and it was confirmed that nucleated epithelial cells and keratinocytes were significantly reduced. The pregnancy period was 21 ± 1.8 days, and the number of live births per delivery was 11.9 on average. The number of fetuses on the 8th and 10th days of pregnancy were 15.2 ± 0.4 and 15.4 ± 0.3, respectively. On the contrary, the number of fetuses on the 12th day of pregnancy was 12.9 ± 0.6, which was significantly (p < 0.05) decreased compared to the 10th day of pregnancy, and the number of fetuses was similar until delivery. As a result of investigating the change of body weight according to the birth weight and growth stage after delivery, the birth weight of female and male was 9.2 ± 2.0 g and 9.8 ± 2.5 g, respectively. After that, until the 16th day, the female and the male showed similarly moderate weight gain, and then showed a rapid weight gain until the 21st day of lactation. With reference to the results of this study, it is expected to be used as basic data for determining the mating time of rodents and controlling pregnancy and fetal number.
Meat and carcass quality attributes are important factors influencing consumer preference and profitability in the pork industry. Single nucleotide polymorphisms (SNPs) are essential for livestock breeding and improvement. In the present study, the pig Perilipin 2 (PLIN2 ) gene was characterized with the aim of detecting genetic variation at these loci in relation to economic traits in Berkshire pigs. Four SNPs (G6714C, G6813A, G10340A, and G10632A) were detected in this studied. Statistical analysis indicated that G6714C was significantly associated with the National Pork Producers Council (NPPC) color score, G6813A, and G10340A significantly affected NPPC color score and NPPC marbling score, and G10632A significantly affected backfat thickness (BF) (p < 0.05). Therefore, the molecular markers used in the present study might provide a useful basis for identification and improvement of traits in the Berkshire pigs.
Behavioral response to a diel photoperiodicity (500 lx for 16 h, 5 lx for 4 h and < 0.5 lx for 4 h) and phototactic characteristics in dark conditions were examined with Siberian sturgeon Acipenser baerii (Chondrostei, Actinopterygii) prelarvae. Siberian sturgeon prelarvae represented both qualitative and quantitative changes in their behavioral patterns according to different light intensities in a diel photoperiodicity. Under daylight conditions (500 lx), prelarvae displayed saltatory changes of behavioral features with ages (Day 0-Day 9) in a general order of swimming-up/drifting, swimming in the upper water column, benthic swimming with rheotaxis, schooling and postschooling behavior. Compared to daylight conditions, prelarvae tended to show more benthic performances and quantitative reductions of schooling and postschooling behaviors under dimlight conditions (5 lx). Under dark conditions (< 0.5 lx), prelarvae exhibited a fairly uniform behavioral pattern characterized by the benthic swimming across the bottom of the tank. From phototaxis tests under dark conditions, navigational responses of prelarvae to a spotlight illumination were quantitatively changed as their ages increased. The phototactic responses reached the peak on Day 2, continued until Day 4, and then gradually decreased until Day 8. A partial recovery of positive phototaxis was observed on Day 9. Data from this study suggest that the diel light cycle as well as the light intensity of each interval in the cycle should be considered as important components of a practical guide for evaluating fitness and developmental states of artificially propagated Siberian sturgeon prelarvae.
This study investigated the effect of variation in the number of somaticcell- cloned embryos and their developmental stage at transfer on pregnancy, as well as the influence of the estrus status of recipient pigs on in vivo development of cloned porcine embryos after embryo transfer. For somatic cell nuclear transfer (SCNT), fibroblast cells were obtained from a male porcine fetus. Recipient oocytes were collected from prepubertal gilts at a local abattoir and then cultured. After SCNT, reconstructed embryos of different numbers and developmental stages were transferred into recipient pigs. The developmental stage of the cloned embryos and the number of transferred embryos per surrogate showed no significant differences in terms of the resulting cloning efficiency. However, the pregnancy rate improved gradually as the number of transferred cloned embryos was increased from 100- 150 or 151-200 to 201-300 per recipient. In pre-, peri-, and post-ovulation stages, pregnancy rates of 28.6%, 41.8%, and 67.6% and 16, 52, and 74 offspring were recorded, respectively. The number of cloned embryos and estrus status of the recipient pig at the time of transfer of the cloned embryo affect the efficiency of pig production; therefore, these variables should be particularly considered in order to increase the efficiency of somatic cell pig cloning.
The congenital head anomalies are most often used to describe defects in the eyes, mouth, nose, skull, and or brain. The faulty embryogenesis most likely found to be associated with abnormal genetic or epigenetic causes during pregnancy. Eventually it leads to congenital anomalies. Rabbit-headed Lamb (RH) is a disorder in sheep breeding that is characterized by some deformities in the head and the face. A dead –day old- crossbred white Najdi lamb with a deformed face and head was reported to be born in the current case. The external and physical examination revealed a deformed skull and facial region with a unilateral eye, fused mouth, piglike nose, and patent skull with the brain coming out from left eye orbit. Additionally, the lamb was very skinny with unusual long extremities. This is the first report of this syndrome that describes such deformities in a stillbirth Najdi breed lamb.
Amniotic membrane stem cells are considered as a good alternative to embryonic stem cells, but their use in clinical studies is still not common. Here, exosomes from canine amniotic membrane mesenchymal stem cells (cAmMSCexo) were used for dog sperm cryopreservation. Upon cryopreserved straws using cryoprotectant containing 0, 0.5, 1, or 2 μg/mL of cAmMSC-exo were thawed, motility and membrane integrity were analyzed. However, results showed no significant differences between the groups. We concluded that cAmMSC-exo with lower than 2 µg/mL have no effects on sperm cryopreservation, and further studies to get higher concentrations of cAmMSC-exo should be conducted for clinical application.
The milk fever and mastitis that occur during the colostrum period in dairy cattle cause great damage in the dairy industry by causing a rapid decline in the cattle’s health and decreasing milk production. In order to prevent this, gradual milking (GM), calcium injection with gradual milking (CG), and calcium injection with complete milking (CC) methods are used. However, differences in effectiveness between these methods have not been established. Therefore, this study was conducted to determine the effects of each preventive method on milk fever and mastitis. The results of this study showed that while there was a significant negative correlation of GM with milk fever and mastitis (r = –0.657, p < 0.05), there was no correlation of CG and CC with milk fever and mastitis. The incidence of milk fever was significantly lower in CG and CC than in GM (p < 0.05) but no differences in the incidence of mastitis were observed between the three groups. No significant differences in the rate of recovery from milk fever and mastitis were observed between the three groups. The recurrence rate of milk fever was significantly higher in CG and CC than in GM (p < 0.05), though no differences in the recurrence rate of mastitis were observed. This study showed an inverse relationship between the incidence rates of milk fever and mastitis when calcium injection was not used during the colostrum period. When calcium injections were used, the incidence of milk fever was reduced without affecting the incidence of mastitis regardless of the milking method, but the recurrence rate of milk fever was increased. The results of this study would be useful for controlling blood calcium concentrations and establishing efficient milking strategy in order to effectively prevent milk fever and mastitis in dairy cattle during the colostrum period.
Changes of gonadal morphology and mRNA expression patterns of vitellogenin were investigated in Siberian sturgeon Acipenser baerii (Chondrostei) during its early gonadal maturation period. Early differentiations and morphological transitions of both ovaries and testes appeared to occur actively until the age of 3 years, however from then on, the maturation patterns to full maturity were largely gender-dependent, in which males showed a faster progression of maturation than did females while females experienced a steady-state progress with a lagged interval before entering the final maturation. Expression of vitellogenin mRNAs are closely correlated with transitional patterns of gonadal appearances. In both females and males, hepatic mRNA levels of vitellogenin exponentially increased in the earliest interval (up to 1-year-old). However, in subsequent periods, vitellogenin expression in females continued to increase with age, whereas in males, the expression stabilized at a younger age. Nevertheless, at the age older than or equal to 7-year-old, fully matured individuals showed a quite low level of vitellogenin expression in both females and males. Collectively, results from this study could be useful as a fundamental guideline to address the gonad maturation of this sturgeon species, which is helpful for making practical decisions about farming practices and management for caviar production on local sturgeon farms.