问题描述:
英语翻译
Abstract
This study evaluated the effects of three types of probiotics,two bacteria and one yeast on growth performance in Nile tilapia.Three diets were formulated containing the optimum protein level(40%) for tilapia fry:one supplemented at 0.1% with a bacterial mixture containing.Streptococcus faecium and Lactobacillus acidophilus;a second supplemented at 0.1% with the yeast Saccharomyces cerevisae;and a third,a control diet without supplements.Two additional diets were formulated to contain 27% protein to serve as a stress factor,and were supplemented at 0.1% with either the bacterial probiotic mix or the yeast.The diets were fed for 9 weeks to tilapia fry stocked in 20-l tanks at two densities:a high density of 20 fry per tank as a stress factor;and a low density of 10 fry per tank.Results indicate that the fry fed with diets with a probiotics supplement exhibited greater growth than those fed with the control diet.Of the four probiotic treatments,the 40% protein diet supplemented with yeast produced the best growth performance and feed efficiency,suggesting that yeast is anappropriate growth-stimulating additive in tilapia cultivation.
D 2003 Elsevier ScienceB.V.All rights reserved.
Keywords:Probiotics;Tilapia; Oreochromis niloticus; Streptococcus; Lactobacillus; Saccharomyces
1.Introduction
The demand for animal protein for human consumption is currently on the rise and is largely supplied with terrestrial farm animals.Aquaculture,however,is an increasingly important option in animal protein production.This activity requires high-quality feeds with high protein content,which should contain not only necessary nutrients but also complementary additives to keep organisms healthy and favor growth.Some of the most utilized growth-promoting additives include hormones,antibiotics,ionophores and some salts (Fuller,1992;Gongora,1998;Klaenhammer and Kullen,1999).Though these do promote growth,their improper use can result in adverse effects in the animal and the final consumer,as well as lead to resistance in pathogenic bacteria in the case of antibiotics.
Though probiotics are widely used in poultry and swine rearing,little has been done to incorporate them into aquaculture.Thus,this study was designed to evaluate the use of a bacteria mix containing Streptococcus faecium and Lactobacillus acidophilus,and the yeast Saccharomyces cerevisiae,as probiotic supplements in diets for Nilet ilapia fry.
2.Materials and methods
The experiment was conducted for 9 weeks,using3-week old Nile tilapia(Oreochro- omis niloticus,152.3 mg average weight) fry obtained from the Aquaculture Laboratory of CINVESTAV in Merida,Yucatan,Mexico.
Abstract
This study evaluated the effects of three types of probiotics,two bacteria and one yeast on growth performance in Nile tilapia.Three diets were formulated containing the optimum protein level(40%) for tilapia fry:one supplemented at 0.1% with a bacterial mixture containing.Streptococcus faecium and Lactobacillus acidophilus;a second supplemented at 0.1% with the yeast Saccharomyces cerevisae;and a third,a control diet without supplements.Two additional diets were formulated to contain 27% protein to serve as a stress factor,and were supplemented at 0.1% with either the bacterial probiotic mix or the yeast.The diets were fed for 9 weeks to tilapia fry stocked in 20-l tanks at two densities:a high density of 20 fry per tank as a stress factor;and a low density of 10 fry per tank.Results indicate that the fry fed with diets with a probiotics supplement exhibited greater growth than those fed with the control diet.Of the four probiotic treatments,the 40% protein diet supplemented with yeast produced the best growth performance and feed efficiency,suggesting that yeast is anappropriate growth-stimulating additive in tilapia cultivation.
D 2003 Elsevier ScienceB.V.All rights reserved.
Keywords:Probiotics;Tilapia; Oreochromis niloticus; Streptococcus; Lactobacillus; Saccharomyces
1.Introduction
The demand for animal protein for human consumption is currently on the rise and is largely supplied with terrestrial farm animals.Aquaculture,however,is an increasingly important option in animal protein production.This activity requires high-quality feeds with high protein content,which should contain not only necessary nutrients but also complementary additives to keep organisms healthy and favor growth.Some of the most utilized growth-promoting additives include hormones,antibiotics,ionophores and some salts (Fuller,1992;Gongora,1998;Klaenhammer and Kullen,1999).Though these do promote growth,their improper use can result in adverse effects in the animal and the final consumer,as well as lead to resistance in pathogenic bacteria in the case of antibiotics.
Though probiotics are widely used in poultry and swine rearing,little has been done to incorporate them into aquaculture.Thus,this study was designed to evaluate the use of a bacteria mix containing Streptococcus faecium and Lactobacillus acidophilus,and the yeast Saccharomyces cerevisiae,as probiotic supplements in diets for Nilet ilapia fry.
2.Materials and methods
The experiment was conducted for 9 weeks,using3-week old Nile tilapia(Oreochro- omis niloticus,152.3 mg average weight) fry obtained from the Aquaculture Laboratory of CINVESTAV in Merida,Yucatan,Mexico.
问题解答:
我来补答展开全文阅读