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Disaccharides have been used as an extender for dromedary camel semen (Bravo et al. 2000 Anim. Reprod. Sci. 62, 173-193). More recently we have investigated the effect of different concentrations of lactose extender on the viability of Bactrian camel spermatozoa (Mosafer et al. 2005 Reprod. Fertil. Dev. 17, 197). Considering the osmolality (316.1 � 1.48 mOsm/kg) and pH (7.4 � 0.03) of Bactrian camel semen (Mosaferi et al. 2005 Theriogenology 63, 92-101), the objective of this study was to investigate the effect of osmolality of sucrose extender on the viability of Bactrian camel spermatozoa. Sucrose at the concentrations of 9, 10, 11, 12, and 13% with osmolalities of 292, 331, 356, 386, and 410 mOsm/kg, respectively, were prepared. All extenders contained 20% egg yolk and antibiotics, with pH adjusted to 6.9. Semen was collected from camels with a sound history of semen quality and fertility (n = 3) using a modified artificial vagina and divided into different treatments after mechanical reduction of semen viscosity (3). Progressive forward motility of spermatozoa was examined at the time of semen collection and at 4, 12, and 24 h after incubation at 4�C. Data were analyzed using the GLM procedure in SAS/STAT after arcsin transformation. At the time of semen dilution, the progressive forward motility of spermatozoa was greater at osmolality of 331 (23%) compared with 292 (1%), 386 (6%), and 410 (3.5%) mOsm/kg (P < 0.05). No progressive forward motility of spermatozoa was noticed after 4 h incubation at 4�C at osmolalities of 292, 386, and 410 mOsm/kg. At this time, a significant decrease (P < 0.05) of progressive forward motility occurred at osmolalities of 331 (4%) and 356 (0.5%) compared with that of the time of dilution. After 12 and 24 h incubation at 4�C, no progressive forward motility of spermatozoa was detected in any of these extenders. In conclusion, 10% sucrose (331 mOsm/kg) at the adjusted pH of 6.9 was the most suitable concentration of this disaccharide for preserving Bactrian camel semen for less than 4 h under chilled conditions.

The objective of this study was to determine the effects of genetic manipulation, cell type, and culture conditions on developmental potential of bovine nuclear transfer (NT) embryos. Ovum pickup (OPU) technology was developed to obtain the oocytes for NT. A total 4044 cumulus-oocyte complexes (COCs) were obtained during 492 OPU sessions, with an average of 8.2 COCs recovered each session. Cultured granulosa cells (CGC), bovine fetal (150 days) oviduct epidermic cells (FOEC), and adult ear skin fibroblasts (ASFC) were used as donor cells for NT and were transfected with the expression vector including human FIX coding sequence directed by goat β-casein promoter and neomycin gene. The cells were screened under 800 µg mL −1 G418 for 10-14 days until the apperance of a "mono-colony" of cells which were then picked. Each cell population was expanded by consecutive passage culture under 300 µg mL −1 G418 until used for NT, ensuring that the majority of cells were transgenic. Oocytes were enucleated at 20 h post-maturation and a single donor cell was transferred into the perivitelline space of a recipient oocyte. After fusion and activation, the reconstructed embryos were co-cultured with vero cells in B2 medium for 7 days. NT efficiency between primary granulosa cells (PGC) without in vitro culture and CGC, as well as among CGC, FOEC and ASFC that were transfected with exogenous DNA (named TCGC, TFOEC, TASFC, respectively), were compared (Table 1). Differences between groups were verified by chi-square test using SAS 6.12 (SAS Institute, Inc., Cary, NC, USA) program. CGCs presented a higher fusion rate (P < 0.01) for reconstructed embryos and higher development to the blastocyst stage for NT embryos than did PGC (67% vs. 54% and 41% vs. 21%, respectively). There were no significant differences (P > 0.05) in cleavage rate (65%, 71%, and 69%, respectively) and development to the blastocyst stage for NT embryos (36%, 30% and 40%, respectively) for TCGC, TFOEC, and TASFC. A total of 86 blastocysts were selected for transfer into uteri of 86 cows, resulting in 26 pregnancies (30%) at 60 days by ultrasound scanning. Among these, 12 cows remain pregnant and 14 have aborted. The results indicated that oocytes recovered from OPU can be successfully used for NT with development to the blasocyst stage. PGC, CGC, FOEC, and ASFC can all be used for generating transgenic cattle by NT, although this needs to be verified by the birth of live calves. The cryopreservation of sperm has contributed greatly to animal breeding and reproduction. This study was designed to examine the effect of raffinose, sucrose, and trehalose as cryoprotectants for freezing of mouse sperm. The cryoprotectant solution (CPA) consisting of 3% skim milk (Skim Milk dehydrated, Bacto, Difco, Seoul, Korea) as buffer or extender was prepared and supplemented with 0.3 M raffinose (D[+]raffinose pentahydrate, Sigma) or sucrose or trehalose as non-permeating cryoprotectants. Sperm samples for cryopreservation were collected from caudae epididymides and vas deferens ...