Extruded soybean meal(ESBM) was evaluated as a protein source for partial replacement of fish meal(FM) in diets of juvenile Litopenaeus vannamei. In the control diet(Diet 1), FM protein was replaced with increasing di...Extruded soybean meal(ESBM) was evaluated as a protein source for partial replacement of fish meal(FM) in diets of juvenile Litopenaeus vannamei. In the control diet(Diet 1), FM protein was replaced with increasing dietary levels of ESBM(4.28%, 8.40%, 12.62%, 16.82%, and 25.26%) at 10%, 20%, 30%, 40%, and 60% levels(Diets 2 to 6, respectively). An eight-week feeding trial was conducted on 720 juvenile shrimp(0.67 g ± 0.01 g mean initial weight), and nutrient digestibility of the six diets was determined. ESBM could replace 20% of FM without causing a significant reduction in growth of shrimp, but other dietary treatments strongly affected whole body composition. Crude protein content of the whole body fed Diet 6 was significantly lower than that fed Diet 2(P < 0.05), while crude lipid content of the whole body fed Diet 5 or 6 was significantly higher than that fed Diet 2(P < 0.05). Protein digestibilities of Diets 5 and 6 were significantly lower than that of Diet 1(P < 0.05). Digestibility of lipids ranged from 96.97% in Diet 6 to 98.34% in Diet 3, whereas dry matter digestibility decreased with increasing replacement level. This study indicates that 20% FM replacement with ESBM in the basic diet containing 40% protein and 30% FM is optimal for juvenile L. vannamei.展开更多
To ascertain the nutrient components and nutritive quality of the flesh of big yellow croaker in three culture conditions （ traditional cage, offshore cage and cage-free）, basic nutritional components,amino acid,fat...To ascertain the nutrient components and nutritive quality of the flesh of big yellow croaker in three culture conditions （ traditional cage, offshore cage and cage-free）, basic nutritional components,amino acid,fatty acid and mineral elements were determined. The results indicated that crude protein in flesh of the big yellow croaker in cage-free culture was higher than that in offshore cage and much higher than that in traditional cage （ P 〈0.05）. Crude fat of the croaker cul- tured in the traditional cage was twice as high as that in cage-free culture, while that in the offshore cage was in the middle. Proline content in the cage-free culture was much higher than that in the offshore cage, and also than that in the traditional cage （P 〈 0.05 ）. There was no significant difference in the content of alanine, methionine and tryptophan （ P 〈 0.05）. Contents of other amino acids had no significant difference between the cage-free culture and offshore cage, but were much lower in the traditional cage （P 〈 0.05 ）. Top six fatty acids were 9-Hexadecenoic acid, palmitic acid,9-Octadecenoic acid, Octadecauoic acid, DHA and EPA. The palmitic acid content was the highest in cage-free culture and in traditional cage, 9-Octadeeenoic acid content was the highest in offshore cage. Content of unsaturat- ed fatty acids in cage-free culture, offshore cage and traditional cage was 63.60,66.32,57.67, respectively, and polyunsaturated fatty acid was 29.10, 28.57, and 24.40. Content of DHA in cage-free culture was significantly higher than that in the offshore and traditional cage. Content of zinc had no significant difference in three culture models. Content of phosphorus had no significant difference between that in cage-free culture and offshore cage, was lower in the traditional cage. The cage-free cultured croakers had the highest content of calcium and phosphorus. Content of selenium was about the same between the offshore cage and the traditional cage stocking, higher in the cage-free culture. This research has considerable application value for identifying quality and sources of the big yellow croakers.展开更多
The paper reviews the recent advances in studying grouper nutrition requirement for the development of cost-effective and environmentally friendly artificial diets. It consists of seven parts: protein and amino acid, ...The paper reviews the recent advances in studying grouper nutrition requirement for the development of cost-effective and environmentally friendly artificial diets. It consists of seven parts: protein and amino acid, lipid and essential fatty acid, carbohydrate, vitamin, mineral, alternative protein source, broodstock and larval nutrition. The review provides some basic information for further investigation of nutrient requirements of groupers.展开更多
Mortality is normal and natural in aquaculture experiments. However, it becomes a problem when measuring feed intake as a component of nutrient utilization parameters such as： feed conversion ratio, feed conversion e...Mortality is normal and natural in aquaculture experiments. However, it becomes a problem when measuring feed intake as a component of nutrient utilization parameters such as： feed conversion ratio, feed conversion efficiency, apparent net protein utilization, protein efficiency ratio and protein productive value. In order to accurately evaluate feed intake with due consideration of mortality encountered, a formulae was developed using empirical data obtained from an experiement that had mortality. The formulae Fwas： total feed consumed by numbers of survived fishes=DL∑i=1n（Fi/Ni）N. Where, D=Numbers of days fishes were fed within each period ibefore it was adjusted（e.g fortnight）, it was constant throught period of experiment; F=Uantity of feed fed per day for a fortnight before the quantity was adjusted, it changed every fortnight; L=Numbers of living fishes at the end of experimental period; N=Numbers of fishes at each weighing period, it might change every fortnight or might be constant if no mortality occurred; while n=Numbers of times fishes were weighed and quantity of feed was adjusted but this did not include the final weighing at the termination of experiment. However, if the fishes were weighed weekly, then D=6.展开更多
基金financially supported by the Special Fund for Agro-scientific Research in the Public Interest of China(201003020)the Guangdong University Innovation Talents Cultivating Project of China(1009324)+1 种基金the Guangdong Natural Science Foundation of China(S2012 040007863)by the Guangdong Province Universities and College Pearl River Scholar Funded Scheme(GD UPS-2011)
文摘Extruded soybean meal(ESBM) was evaluated as a protein source for partial replacement of fish meal(FM) in diets of juvenile Litopenaeus vannamei. In the control diet(Diet 1), FM protein was replaced with increasing dietary levels of ESBM(4.28%, 8.40%, 12.62%, 16.82%, and 25.26%) at 10%, 20%, 30%, 40%, and 60% levels(Diets 2 to 6, respectively). An eight-week feeding trial was conducted on 720 juvenile shrimp(0.67 g ± 0.01 g mean initial weight), and nutrient digestibility of the six diets was determined. ESBM could replace 20% of FM without causing a significant reduction in growth of shrimp, but other dietary treatments strongly affected whole body composition. Crude protein content of the whole body fed Diet 6 was significantly lower than that fed Diet 2(P < 0.05), while crude lipid content of the whole body fed Diet 5 or 6 was significantly higher than that fed Diet 2(P < 0.05). Protein digestibilities of Diets 5 and 6 were significantly lower than that of Diet 1(P < 0.05). Digestibility of lipids ranged from 96.97% in Diet 6 to 98.34% in Diet 3, whereas dry matter digestibility decreased with increasing replacement level. This study indicates that 20% FM replacement with ESBM in the basic diet containing 40% protein and 30% FM is optimal for juvenile L. vannamei.
基金Sponsored by Research Program of Zhejiang Provincial Department of Education(Y201328411)Program of Zhejiang Provincial Department of Science and Technology(2009C22007)
文摘To ascertain the nutrient components and nutritive quality of the flesh of big yellow croaker in three culture conditions （ traditional cage, offshore cage and cage-free）, basic nutritional components,amino acid,fatty acid and mineral elements were determined. The results indicated that crude protein in flesh of the big yellow croaker in cage-free culture was higher than that in offshore cage and much higher than that in traditional cage （ P 〈0.05）. Crude fat of the croaker cul- tured in the traditional cage was twice as high as that in cage-free culture, while that in the offshore cage was in the middle. Proline content in the cage-free culture was much higher than that in the offshore cage, and also than that in the traditional cage （P 〈 0.05 ）. There was no significant difference in the content of alanine, methionine and tryptophan （ P 〈 0.05）. Contents of other amino acids had no significant difference between the cage-free culture and offshore cage, but were much lower in the traditional cage （P 〈 0.05 ）. Top six fatty acids were 9-Hexadecenoic acid, palmitic acid,9-Octadecenoic acid, Octadecauoic acid, DHA and EPA. The palmitic acid content was the highest in cage-free culture and in traditional cage, 9-Octadeeenoic acid content was the highest in offshore cage. Content of unsaturat- ed fatty acids in cage-free culture, offshore cage and traditional cage was 63.60,66.32,57.67, respectively, and polyunsaturated fatty acid was 29.10, 28.57, and 24.40. Content of DHA in cage-free culture was significantly higher than that in the offshore and traditional cage. Content of zinc had no significant difference in three culture models. Content of phosphorus had no significant difference between that in cage-free culture and offshore cage, was lower in the traditional cage. The cage-free cultured croakers had the highest content of calcium and phosphorus. Content of selenium was about the same between the offshore cage and the traditional cage stocking, higher in the cage-free culture. This research has considerable application value for identifying quality and sources of the big yellow croakers.
文摘The paper reviews the recent advances in studying grouper nutrition requirement for the development of cost-effective and environmentally friendly artificial diets. It consists of seven parts: protein and amino acid, lipid and essential fatty acid, carbohydrate, vitamin, mineral, alternative protein source, broodstock and larval nutrition. The review provides some basic information for further investigation of nutrient requirements of groupers.
文摘Mortality is normal and natural in aquaculture experiments. However, it becomes a problem when measuring feed intake as a component of nutrient utilization parameters such as： feed conversion ratio, feed conversion efficiency, apparent net protein utilization, protein efficiency ratio and protein productive value. In order to accurately evaluate feed intake with due consideration of mortality encountered, a formulae was developed using empirical data obtained from an experiement that had mortality. The formulae Fwas： total feed consumed by numbers of survived fishes=DL∑i=1n（Fi/Ni）N. Where, D=Numbers of days fishes were fed within each period ibefore it was adjusted（e.g fortnight）, it was constant throught period of experiment; F=Uantity of feed fed per day for a fortnight before the quantity was adjusted, it changed every fortnight; L=Numbers of living fishes at the end of experimental period; N=Numbers of fishes at each weighing period, it might change every fortnight or might be constant if no mortality occurred; while n=Numbers of times fishes were weighed and quantity of feed was adjusted but this did not include the final weighing at the termination of experiment. However, if the fishes were weighed weekly, then D=6.
