Resources

Description

Feed particle size requirements for crucian carp of 2-cm to 7-cm total length were determined in a joint study by ASA and the Zhejiang Freshwater Fisheries Research Institute in Huzhou, China. Results were used to formulate feed size recommendations for fish farmers producing crucian carp using feed-based production technologies. Crumble feeds of size 0.5-mm and 1.0-mm are recommended for fry of 2-cm and 3-cm total length, respectively. Crucian carp fry can be weaned to a 1.5-mm extruded pellet at 5-cm total length.

Language
English

Date Published
October 31, 1999

Author
Michael C. Cremer and Zhang Jian
Description

Grass carp were grown from fry to fingerlings on two feed regimes using the ASA 80:20 production model and soy-based feeds. Grass carp grew from 0.3 g to 83 g when fed a 36% protein, soy-based diet for the entire production season. Grass carp grew from 0.3 g to 78 g when fed a 36% protein, soy-based diet to size 25 g, followed by feeding with a 32% protein, soy-based diet thereafter. Growth was significantly different with the two feed regimes. FCR for the 36% protein feed regime was 1.12:1 for the 121-day feeding period. FCR for the combination feed regime was 1.19:1. No economic benefit was obtained by reducing the protein content of the feed once grass carp reached 25g in weight. The reduction in feed cost obtained with the combination feed regime was offset by the better growth performance of fish receiving the 36% protein feed for the duration of the production season.

Language
English

Date Published
October 31, 1999

Author
Michael C. Cremer and Zhang Jian
Description

Two fingerling sizes of grass carp were grown to market size in ponds using the ASA 80:20 production model and a soy-based diet. Fish were stocked at 600 grass carp per mu together with 100 silver carp per mu. Fingerlings of sizes 70 g and 100 g grew respectively to 797 g and 827 g in 178 days of feeding. Net production for the three, 100-g fingerling ponds averaged 438 kg/mu of grass carp and 113 kg/mu of silver carp. Net production for the three, 70-g fingerling ponds averaged 429 kg/mu of grass carp and 108 kg/mu of silver carp. The 100-g fingerlings reached a target market size of 750 g in 156 days, while the 70-g fingerlings reached 750 g in 165 days. FCR with the ASA all- plant protein, soy-based diet was 1.22 for the 70-g fingerlings and 1.19 for the 100-g fingerlings. Use of this diet in the extruded, floating form allowed the Xu Xing Zhang farm manager to closely monitor fish feeding performance and fish health and prevented over-feeding of fish and wasting of feed. Net economic return and return on investment were RMB 804/mu and 24% for the 70-g fingerling treatment, and RMB 449/mu and 11.7% for the 100-g fingerling treatment.

Language
English

Date Published
October 31, 1999

Author
Michael C. Cremer and Zhang Jian
Description

Japanese Sea Bass (Lateolabrax japonicus) growth in cages was evaluated with two ioscaloric and isonitrogenous feed rations formulated to contain 43% protein and 12% fat. One ration was formulated predominantly with fishmeal, while the other ration contained 40% dehulled soybean meal. Fish were stocked in 8.0-m3 cages at 350 fish per m3 and fed for 153 days. Sea bass grew from 3 g to 297g with the soy-based ration, and from 3 g to 289 g with the fishmeal-based ration. There was no significant difference in fish growth (P>0.05) with the two feeds. FCR averaged 1.53:1 and 1.55:1 for the soy-based and fishmeal-based rations, respectively. Survival averaged 50% for all cages and treatments. This was the first phase of a two-phase trial. Fish will be grown to a >500 g market size during the year 2000 phase two component of the trial.

Language
English

Date Published
October 31, 1999

Author
Michael C. Cremer and Zhang Jian
Description

Pompano (Trachinotus ovatus) growth in cages was evaluated with fishmeal and soybean meal based feed rations. Two ioscaloric and isonitrogenous feed rations were formulated to contain 43% protein and 12% fat. One ration was formulated predominantly with fishmeal, while the other ration contained 40% dehulled soybean meal. Fish were stocked in 1.5-m3 cages at 400 fish per m3 and fed for 150 days. Pompano grew from 2.7 g to 222 g with the soy-based ration, and from 2.7 g to 218 g with the fishmeal-based ration. There was no significant difference in fish growth (P>0.05) with the two feeds. FCR averaged 2.13:1 and 2.23:1 for the soy-based and fishmeal-based rations, respectively. Survival averaged 72% for all cages and treatments. Net economic return was 12% higher and return to investment was 10% greater with the soy-based ration. Production of pompano in cages with manufactured feeds was demonstrated to be both technically and economically feasible. Replacement of fishmeal with dehulled, high protein soybean meal resulted in no reduction in fish growth and a significant cost savings for feed.

Language
English

Date Published
October 31, 1999

Author
Michael C. Cremer and Zhang Jian
Description

A feeding demonstration was conducted in Harbin in 1999 to demonstrate the advantages of ASA’s 80:20 pond technology and soy-based diets for producing bigmouth buffalo fingerlings. Bigmouth buffalo fry with an average weight of 0.5 g were stocked in two 7-mu ponds in Harbin in May and fed soy-based feeds for 106 days between June and September. The fry grew from 0.5 g to 60 g during this period, with an average FCR of 0.93:1. Net production averaged 244 kg/mu of bigmouth buffalo fingerlings and 62 kg/mu of silver carp fingerlings. Average survival for bigmouth buffalo was 83%. Net economic return was RMB 4,108/mu, with a 114% return to investment. The trial successfully demonstrated the value of the 80:20 technology and both the production and economic advantages of soy-based aquafeeds.

Language
English

Date Published
October 31, 1999

Author
Michael C. Cremer and Zhang Jian
Description

Hybrid wuchang bream (Megalobrama hoffmanni) were grown to market size in ponds using the ASA 80:20 production model and an extruded, soy-based feed. Hybrid wuchang bream grew from 64g to 508 g in 184 days at a stocking density of 800 fish per mu. Net production in three, approximately 5-mu ponds averaged 293 kg/mu of wuchang bream and 71 kg/mu of silver carp. FCR with the ASA soy-based feed was 1.97:1. Net economic return was RMB 634/mu, with a 16.1% return to investment.

Language
English

Date Published
October 31, 1999

Author
Michael C. Cremer and Zhang Jian
Description

A 10-day feeding demonstration was conducted at Rao Ping, Guangdong Province, to determine if coastal aquaculture species could be weaned from a fresh fish diet to extruded, manufactured feeds. Sea bass weighing 55 g and 110 g, red drum weighing 150 g, and juvenile snapper sea bream 5-6 cm in length were tested in the demonstration. All species and all sizes of fish were successfully weaned to extruded feed pellets. Sea bass readily consumed extruded pellets on the second day of the weaning process. Snapper sea bream of size 5-6 cm consumed extruded pellets on the first day pellets were presented. Red drum was the most difficult of the species tested to wean to extruded pellets.

Language
English

Date Published
October 31, 1999

Author
Michael C. Cremer and Zhang Jian
Description

The American Soybean Association (ASA), in cooperation with the China National Fisheries Extension Center (NEC) and its affiliate provincial agencies, has conducted a series of feeding trials with tilapia in ponds and cages over the past five years. These trials have been conducted on commercial fish farms throughout China, and have tested a variety of feeds and feed formula variations to determine the technical and economic feasibility of culturing tilapia in feed-based pond (80:20 technology) and cage (LVHD technology) production systems with soybean-based aquafeeds. These efforts were continued in 1997 with a feeding trial in Guangzhou that evaluated hybrid tilapia growth performance from fry to market size on soybean-based fingerling and grow-out diets.

Language
English

Date Published
October 31, 1997

Author
M. C. Cremer and Zhang Jian
Description

The American Soybean Association (ASA), in cooperation with the China National Fisheries Extension Center (NEC) and its affiliate provincial agencies, has conducted a series of production trials with native and imported fish species since 1991 to demonstrate and evaluate the technical and economic feasibility of feed-based fish culture in China. Tilapia have been one of the key imported species evaluated for both pond and cage production in China. ASA continued its evaluation of tilapia in 1997 with a feeding trial that examined the production performance of red tilapia in LVHD cages with soybean meal-based feeds.

Language
English

Date Published
October 31, 1997

Author
M.C. Cremer and Zhang Jian
Description

Fourteen pond trials were conducted in 1995 and 1996 to assess the fingerling to market growth of crucian carp, pacu, tilapia and wuchang carp (bream) with a variety of aquafeed formulations. The objective of the trials was to test and demonstrate the technical and economic feasibility of production of these species in 80:20 culture systems with feeds formulated primarily from plant proteins. An all-plant protein diet (‘J’) was tested against similar diets (‘H’ and ‘K’) containing primarily plant protein and 5% fish meal.

The all-plant protein ‘J’ diet produced as good or better growth than the ‘H’ diet containing fish meal with crucian carp. Crucian carp of approximately 50 g grew to an average of 227 g in six trials. The production target of 250 g was reached in only two trials. Float and sink forms of the test diets produced inconsistent results. Observations indicate crucian carp are not aggressive feeders and may require training at the fry to fingerling stage to readily adapt to floating feeds. Economic return with crucian carp was highly variable.

Pacu reached the production target of >400 g in two trials conducted and with all three diets tested (‘H’, ‘J’ and ‘K’). There was no difference in pacu growth among the test diets, or among floating and sinking forms of the ‘H’ diet. Feed conversion ratios of 1.2-1.6 indicated rapid and economical growth of pacu on all diets.

Nile tilapia growth was best on the ‘K’ diet, although tilapia grew rapidly on both the ‘J’ and ‘K’ diets tested in one trial in 1995. Average daily growth rates were 8.3% and 9.7% of body weight, respectively, with 31-g fingerlings growing to 355-410 g in 126 days. A 1996 trial stocked fingerlings of 6 g that were unable to attain market size by the end of the production season. There was no growth difference of fingerlings with the ‘J’ and ‘H’ feeds.

Bream growth was also better on the ‘K’ diet, with only minor variations in growth among the ‘H’ and ‘J’ diets in three trials. Floating feeds produced better growth than sinking feeds with bream. Average bream growth, feed conversion ratio and economic return with the three diets was 356 g, 1.8 and Y3255/mu.

Language
English

Date Published
October 31, 1996

Author
H.R. Schmittou, Zhang Jian and M.C. Cremer
Description

Twenty-three cage trials were conducted in 1995 and 1996 to assess fry-fingerling and fingerling-market production potential of Nile tilapia, common carp, crucian carp, wuchang carp (bream), and channel catfish in low-volume high-density (LVHD) cages. The objective of the trials was to test and demonstrate the technical and economic feasibility of production of these species in LVHD cage culture systems with feeds formulated primarily from plant proteins. An all-plant protein diet was tested against similar diets containing 5-10% fish meal.

The all-plant protein ‘J’ diet produced as good or better growth than the ‘H’ and ‘K’ diets containing 5% fish meal in 6 of 8 comparison trials with nile tilapia, 5 of 7 trials with common carp, and all trials with crucian carp and bream. Nile tilapia averaged daily weight gains of 5.4% and 3.1% per day for 50 g and >96 g fingerlings, respectively. Average net income was Y335/m3 ($40.55/m3) for all Nile tilapia trials reporting economic data. Highest net income was Y562/m3 ($68.04/m3) with the ‘J’ floating feed. Nile tilapia fry to fingerling production inLVHD cages was technically and economically feasible, with average net economic returns of Y360/m3 ($43.58/m3).

Common carp did not demonstrate a requirement for fishmeal in formulated feeds. Fish in seven cage trials gained an average of 2.6% of body weight per day on all diets tested. Best comparative growth performance was with the ‘H’ and ‘J’ feeds. The ‘H’ feed produced 7-13% better growth than the ‘K’ feed in two comparison trials. There were no differences in growthwith the ‘K’ and ‘S’ feeds in one comparative trial. Stocking density had no effect on common carp growth. Fish at 400-500/m3 grew at an average rate of 2.65% of body weight per day, while fish at 270-300/m3 grew at an average rate of 2.5% of body weight per day.

Crucian carp fingerlings of 20-26 g did not attain a target market size of 250 g in two cage production trials. Maximum growth with 26-g fingerlings was 177 g with the ‘J’ feed. Stocking of larger fingerlings is indicated to reach market size by the end of the production season. Average FCR of 2.45 was high and indicates a need to modify feed formulations for crucian carp in cages.

Bream did not demonstrate a requirement for fishmeal in one LVHD trial conducted. Floating forms of the ‘H’ and ‘J’ feeds produced 6.7% better growth than the sinking forms of the feedsat the 330/m3 density tested. Fingerling stocking size of 35 g was too small to produce market size fish in this trial.

Language
English

Date Published
October 31, 1996

Author
H.R. Schmittou, Zhang Jian and M.C. Cremer1
Description

Vitamin C is known to perform numerous biochemical and physiological functions in both plant and animal metabolism (Tolbert, 1979). Most animals can synthesize this vitamin in the form of ascorbic acid in amounts sufficient to prevent the clinical symptoms of deficiency collectively known as scurvy. However, primates, guinea pigs, fish, shrimp, and some insects, bats, and birds require a dietary source of vitamin C to prevent or reverse scorbutic symptoms. Among these species, dietary essentiality of vitamin C in fish and shrimp probably results from an absence or insufficiency of L- gulonolactone oxidase (Wilson, 1973; Yamomoto et al., 1978). This enzyme is required for biosynthesis of ascorbic acid from glucose or other simple precursors (Lehninger, 1971).

Language
English

Date Published
October 30, 1979

Author
Tim O’Keefe