Title: | Growth enhancement of fowls by dietary administration of recombinant yeast cultures containing enriched growth hormone |
Author(s): | Chen CM; Cheng WT; Chang YC; Chang TJ; Chen HL; |
Address: | "Department of Zoology, College of Life Science, National Chung Hsing University, Taichung, Taiwan. chchen1@gragon.nchu.edu.tw" |
DOI: | 10.1016/s0024-3205(00)00797-9 |
ISSN/ISBN: | 0024-3205 (Print) 0024-3205 (Linking) |
Abstract: | "In present study the methylotrophic yeast, Pichia pastoris, was used to express a recombinant growth hormone (rGH) gene of swine. A synthetic secretion cassette was constructed using the promoter of the alcohol oxidase1 gene (AOX1), and a alpha-factor signal peptide. After electroporatic transformation and zeocin selection, several clones exhibited high levels of rGH protein expression constituting more than 20% of total yeast protein. Over 95% of rGH was shown to be export into the culture supernatant. Yeast transformant containing the highest recombinant growth hormone level (rGH yeast) and native GS115 Pichia pastoris (non-rGH yeast, as a control) were separately cultured, harvested and adsorbed by wheat bran. Yeast cultures of four dosages (0.05, 0.1, 0.2, and 0.4%) were mixed respectively with chick basal diet and fed to simulated country chickens for 9 weeks. The results showed that, when compared to control chicks, the percentage of body weight gain was improved significantly (P<0.05) in chicks fed with diets containing 0.1 or 0.2% rGH-rich yeast culture at brooding stage, and in chicks fed with 0.4% rGH-rich yeast culture at growing stage. The average weight gain in rGH yeast treated groups for the full-term (0 to 63d) and short term (43 to 63d) of growth were 10.6 and 9.4%, respectively, better than the non-rGH yeast control group. These experimental data suggest that the use of rGH-containing yeast as a supplement in fed provided an alternative approach for growth improvement in simulated country chickens" |
Keywords: | "Alcohol Oxidoreductases/genetics Amino Acid Sequence Animal Feed Animals Base Sequence Chickens/*growth & development Cloning, Molecular *Dietary Supplements Growth Hormone/administration & dosage/*genetics Mating Factor Peptides/genetics *Pichia/genetics;" |
Notes: | "MedlineChen, C M Cheng, W T Chang, Y C Chang, T J Chen, H L eng Comparative Study Research Support, Non-U.S. Gov't Netherlands 2000/11/01 Life Sci. 2000 Sep 15; 67(17):2103-15. doi: 10.1016/s0024-3205(00)00797-9" |