Optimization of parthenogenetic activation of rabbit oocytes and development of rabbit embryo by somatic cell nuclear transfer

The present study explored a suitable parthenogenetic activation (PA) procedure for rabbit oocytes and investigated the developmental potential of somatic cell nuclear transfer (SCNT) embryos using rabbit foetal fibroblasts (RFFs). The electrical activation had the optimal rate of blastocyst (14.06%) when oocytes were activated by three direct current (DC) pulses (40 V/mm, 20 μs each) followed by 6‐dimethylaminopurine (6‐DMAP) and cycloheximide (CHX) treatment; the blastocyst rate of ionomycin (ION) + 6‐DMAP + CHX (12.07%) activation was higher than that of ION + 6‐DMAP (8.6%) activation or ION + CHX (1.24%) activation; there was no significant difference in blastocyst rate between ION + 6‐DMAP + CHX and DC + 6‐DMAP + CHX groups. The blastocyst rate of ION + 6‐DMAP + CHX‐activated oocytes in the basic rabbit culture medium (M‐199) + 10% foetal bovine serum (FBS; 14.28%) was higher than that in buffalo conditioned medium (5.75%) or G1/G2 medium (0), and the blastocyst rate was increased when M‐199 + 10% FBS was supplemented with amino acids. Refreshing culture medium every day or every other day significantly increased the blastocyst rate. Treatment of donor cells with 0.5% FBS for 3–5 days increased blastocyst rate of SCNT embryos (33.33%) than no serum starvation (22.47%) or 0.5% FBS treatment for 6–9 days (23.61%); the blastocyst rate of SCNT embryos derived from nontransgenic RFFs was higher than that derived from transgenic RFFs by electroporation. The blastocyst development ability of SCNT embryos derived from RFFs by electroporation (32.22%) was higher than that of liposome (19.11%) or calcium phosphate (20.00%) transfection, and only the embryos from electroporation group have the EGFP expression (24.44%). In conclusion, this study for the first time systematically optimized the conditions for yield of rabbit embryo by SCNT.     

Spatial distributions of metal(loid)s and their transport in agricultural soils around abandoned metal mine sites in South Korea

Journal of Soils and Sediments - To develop efficient strategies and methods to remediate soils contaminated by metal(loid)s, it is vital to monitor the metal(loid)s in the soil by conducting field...     

Re: Use of polymerase chain reaction for the differentiation of Group A bovine rotavirus G6, G8, and G10 genotypes in the North Island of New Zealand

Extract

In the paper by L Howe, H Sugiarto and RA Squires published in the New Zealand Veterinary Journal 56, 218–221, 2008, entitled, “Use of polymerase chain reaction for the differentiation of Group A bovine rotavirus G6, G8, and G10 genotypes in the North Island of New Zealand”, the authors concluded that “Currently, the rotavirus vaccine available in New Zealand contains only the G6 strain, and may not provide optimal protection for animals infected with G10 rotavirus. … This information may be of assistance in the development and optimisation of vaccines, and enhancement of effective control strategies.”     

苦竹在炼山后生长恢复情况调查研究

研究杉木林下的苦竹,在杉木采伐、炼山后的恢复生长情况.研究表明苦竹具有很强的生长能力,在无人工促进情况下,前两年新竹的平均直径分别为0.47 cm、0.58 cm,平均高度为54.7 cm、109.3cm,新竹数量16.7株·m-2、9.4株·m-2,郁闭度为0.33、1.0;地上部生物量为965 g·m-2、1 071g·m-2,其中叶片的生长量较秆、茎大,约占地上部生物量的一半.前两年间的生物量无显著差异.     

黑龙江省北安所大豆育种回顾与展望

北安所育成的北丰系列大豆对黑龙江省乃至全国大豆产业做出了突出贡献,对北丰系列大豆的育种进程进行全面细致的归纳和总结.     

Colloid Osmotic Pressure of Parenteral Nutrition Components and Intravenous Fluids

Objective: Parenteral nutrition is an important part of therapy for critically ill animals that cannot tolerate enteral feedings. It has been hypothesized that parenteral nutrition might also play a role in increasing colloid osmotic pressure (COP). The purpose of this study was to measure COP of various parenteral nutrition components and compare them to the COP of commonly used intravenous solutions.
Design: Membrane colloid osmometry was used to measure the COP of parenteral nutrition components (lipids, Abstractamino acids, dextrose solutions) and of synthetic colloids, crystalloids, and blood products.
Main Results: Parenteral nutrition components and all crystalloid solutions had COP measurements < 1 mm Hg. Great variation in COP was found in the different artificial colloids and blood products. The COP of the artificial colloids tested ranged from 32.7 ± 0.2 mm Hg for hetastarch to 61.7 ± 0.5 mm Hg for dextran 70.
Conclusions: The results of this in vitro study suggest that parenteral nutrition does not directly contribute to an increase in oncotic pressure. Further studies are needed to determine whether parenteral nutrition may indirectly influence COP in vivo. Knowing the COP of a fluid, along with its other properties, is useful in making appropriate therapeutic decisions.     

Fibrin–alginate hydrogel supports steroidogenesis,in vitro maturation of oocytes and parthenotes production from caprine preantral follicles cultured in group

This study aimed to establish a culture system that improves the in vitro development of caprine preantral follicles. In a first experiment, follicles were encapsulated as a single unit per bead and cultured singly or in groups or with five follicles in the same alginate (ALG) bead for 18 days. In a subsequent experiment, the “five follicles per bead” design was chosen to culture in ALG, fibrin–alginate (FA) or hyaluronate (HA) for 18 days. In a third experiment, we chose the five follicles per bead in FA to culture for 30 days. The culture set‐up of five follicles per ALG bead increased antrum formation and follicle diameter compared to the other culture designs (p < .05). Moreover, under this condition, 44.44% of the oocytes from in vitro cultured preantral follicles reached meiotic resumption. A significant increase of follicle diameter occurred in attachment system and FA (p < .05), but the ALG condition reached the highest among all groups on day 18 (p < .05). Follicles encapsulated in matrix produced more estradiol and progesterone than attachment system (p < .05). The expression of MMP‐9 mRNA was higher in FA than in other groups (p < .05) and similar to antral follicles from in vivo control (p > .05). Only FA group resulted in oocytes matured. After 30 days, oocytes from preantral follicles in vitro grown in FA developed to eight‐cell parthenotes. In conclusion, a culture system using FA supported the development of caprine preantral follicles cultured in group and included in the same bead of hydrogel, improving the oocyte maturation and producing parthenotes.