RESUMEN
A total of 200 26-day-old crossbred weaning piglets ((Yorkshire × Landrace) × Duroc; 6.55 ± 0.62 kg) were used in a 6-week experiment to evaluate the effects of adding probiotics complex supplementation (Syner-ZymeF10) with high and low ZnO diets on the performance of weaning pigs in 42 days. Pigs were randomly allotted to a 2 × 2 factorial arrangement and they were supplemented with two concentration level of ZnO with 3000 ppm and 300 ppm and probiotics complex supplementation with 0 and 0.1%. There were ten replicate pens per treatment with five pigs per pen (two gilts and three barrows). Pigs fed diets with 3000 ppm ZnO had a higher BW during the overall period and ADG during d 8-21, d 22-42, and overall period than pigs receiving 300 ppm ZnO diets (p < 0.05), as well as a G: F which tended to increase on d 8-21 and overall period (p < 0.1) and decreased tendency on faecal gas emission of methyl mercaptans and acetic acid concentration (p < 0.1). Dietary probiotics complex supplementation had decreased the E. coli count (p < 0.05) and tended to increase the Lactobacillus count (p < 0.1). Dietary probiotics complex supplementation and different level of ZnO supplementation had no significant effect on the nutrition digestibility and faecal score (p > 0.05). In conclusion, probiotic supplementation reduced the fecal E. coli counts and tended to improve Lactobacillus counts. There were no interactive effects between ZnO and probiotic complex supplementation on all the measured parameters.
RESUMEN
The population genetic structure of Isaria cicadae, which caused enzootic of cicadas nymphs in three regions, was analyzed by ISSR marker. The results showed that all three enzootic populations showed high genetic diversity with the highest in the Jingtingshan population and the lowest in the Shitai population. The UPGMA clustering analysis revealed that different enzootic populations did not have a predominant lineage but were polyphyletic and heterogeneous. Genetic lineages had nothing to do with geographical origin. However, two subpopulations of Jingtingshan from different sampling periods were gathered into different clades, which exhibited remarkable temporal heterogeneity. The genetic differentiation (Gst) among populations (subpopulations) was 0.2153 and the gene flow was low at 0.9110 (Nmï¼1), which indicated the low gene flow was one of the main reasons for the genetic variation in the population. Therefore, high heterogeneity and low dominance might be genetic structure characteristics of I. cicadae population causing enzootic of cicada nymphs.
Asunto(s)
Variación Genética , Hemípteros/genética , Animales , Genética de Población , Repeticiones de Microsatélite , Ninfa , FilogeniaRESUMEN
In order to study the important factors involved in cationic liposome-mediated gene transfer, Lipofectamine 2000 or DOTAP was evaluated using three types of cells (Hep-2, MCF-7 and SW-480) in vitro transfection efficiencies. Different properties of the two reagents were analyzed and compared by DNA arrearage assay and MTT assay. Both Lipofectamine 2000 and DOTAP had strong capability to combine with DNA; Lipofectamine 2000 can get higher transfection efficiency of the three cells by using GFP as report gene, meanwhile, DOTAP can also get higher transfection efficiency against Hep-2 cell. However, DOTAP showed lower transfection efficiency against MCF-7 and SW-480 cell. On the other hand, the cytotoxicity assay showed that over 85% cell viability of MCF-7 cell could be achieved both by Lipofectamine 2000 and DOTAP under the optimal transfection condition. Relatively speaking, Lipofectamine 2000 has very high transfection efficiency in a broad range of cell lines, but because of the special selectivity of cell type on liposome, DOTAP also has a broad application prospect.