摘要:

AbstractAn international cooperative effort to evaluate two possible Standard Reference Diets (SRD) for crustaceans was initiated at an informal discussion on crustacean nutrition during the 1984 World Mariculture Society (WMS) meeting in Vancouver, B.C. One diet, BML 81 S, was developed at the Bodega Marine Laboratory, University of California, Davis. The other, HFXCRD 84, was developed at the Halifax laboratory, Department of Fisheries and Oceans, Canada. Details of the formulation, preparation and proximate composition of the diets are provided. Both of these diets, which had been used to culture lobster,Homarussp., were compared with the usual control diets of several research teams from different countries in feeding trials with many different species of crustaceans including freshwater and marine shrimp, prawn, lobster, crayfish and crab.The preliminary data on growth and survival ofPandalus danae, Penaeus monodon, P. stylirostris, P. vannamei, P. brasiliensis, P. setiferus, P. aztecusandHomarus americanussuggest that either BML 81 S or HFX CRD 84 would be an acceptable SRD for these species. The only species tested that would not accept either diet werePanulirus argusandCherux tenuimanus. Use of an SRD will provide a more accurate assessment of non‐nutritional growth factors and permit comparisons among laboratories, species and experiment

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00560.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

AbstractObtaining reliable results from comparative crustacean nutrition studies requires a dietary reference protein which is available world‐wide and is nutritionally optimal for growth and survival. Traditional protein sources include “vitamin free” casein, egg albumin, whole egg protein, soybean protein, and others. These have proven to be inadequate for juvenile lobster (Homrus americanus). Purified rock crab (Cancer irroratus) protein is proposed to be nutritionally superior to casein for inclusion in semi‐purified lobster diets.Eighteen week feeding trials with juvenileH. americanuswere conducted to compare diets containing protein obtained from rock crabs (Cancer irroratus), and produced by several different purification processes with a control diet having casein as its primary protein source. Diets containing purified rock crab protein were found to be superior to the control diet. Among the differently derived purified rock crab protein products, the precooked, isopropanol‐purified was the most effective dietary i

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00561.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

AbstractTwo proposed standard reference diets for use in studies of crustacean nutrition were evaluated using newly metamorphosed postlarvae of the fresh water prawnMacrobrachium rosenbergii, After 90 days, no significant differences in mean whole wet weight or time interval between successive molts of the two dietary treatment group existed. The dietary amino acid composition of each diet and the corresponding amino acid composition of either the whole body or tail muscle tissue were highly correlated. There was a poor correlation between the dietary amino acid composition and the free amino acid composition of whole body and tail muscle tissue. Both diets could adequately serve as reference diets for nutritional studies with juvenileM. rosenbergii.

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00562.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

AbstractJuvenile Australian freshwater crayfish (Cherax tenuimanus) were individually housed in an experimental battery system and fed HFX CRD 84 and BML 81 S, two proposed standard reference diets for studies of crustacean nutrition. The HFX CRD 84 diet was accepted more readily than the BML 81 S diet. After 100 days, mean weight gain of marron fed the HFX CRD 84 diet was significantly greater than that of those fed the BML 81 S diet. Growth rate, measured 118 percent weight pin per ecdysis, declined during three successive 50 day periods. Growth on the proposed reference diets ranged from 16 to 33% of that achieved with pond raised marron of similar age. Both diets may be useful in the development of species specific modifications relative to nutrient composition.

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00563.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

AbstractAn experiment was conducted to measure the survival and growth of juvenile Dungeness crabs (Cancer magister) when fed purified crustacean diets in intensive laboratory culture. Wild‐caught juvenile crabs were held individually and fed either a casein‐based diet previously used for lobster experimentation (diet BML‐81 S), a crab protein‐based diet (HFX‐CRD‐84), or a closed‐formula commercial fish (trout) diet. Diets BML‐81 S and HFX‐CRD‐84 have been proposed as possible general crustacean reference diets. The crab protein‐based diet appeared to be more attractive to the crabs, but after a 90 day experimental period there were no significant differences (P<0.01) in growth or survival between crabs fed the proposed reference diets; however, survival on the trout diet was significantly reduced. Results are discussed in relation to the rearing conditions and the composition and physical charact

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00564.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

AbstractAdult red swamp crayfish (Procambarus clarkii) were held in fecal collection chambers and fed common feedstuffs in two different types of diets, as the sole feedstuff and as a 30% substitution in a reference diet. Feedstuffs tested were soybean meal, peanut meal, wheat shorts, cooked corn, menhaden fish meal, and shrimp‐head meal. Feed consumption, apparent digestible dry matter, and energy coefficients were determined for feedstuffs when fed in both diets. Addition of menhaden fish meal, shrimp‐head meal, and peanut meal in the reference diet resulted in decreased consumption, and menhaden fish meal was poorly digested when incorporated at 30% in the reference diet. Apparent dry matter and energy digestion coefficients Indicated that plant feedstuffs have greater potential as ingredients in crayfish diets than feedstuffs of animal origin. Differences in consumption and digestibility between the two types of diet were observed. Therefore, it appears that the associative effects of additions of feedstuffs in diets should be considered when formulating crayfish fe

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00565.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

AbstractDecapsulation ofArtemiaspp. cysts in strong hypochlorite solutions reportedly increases the number of nauplii that hatch. Commercial cysts ofArtemia franciscanowere subjected to four decapsulation methods prior to hatching them in aerated seawater. Samples were removed from the hatch vessels every 5 h from 15 through 45 h, and fully hatched nauplii were counted. The experiment was performed three times. No significant difference was seen between mean numbers of control nauplii and nauplii obtained using the decapsulation method that yielded the best hatch: oxidation for 15 min in equal parts Clorox® and seawater plus 6 mL of a 40% NaOH solution, followed by reduction with 100 mL of 0.7Msodium thiosulfate. A third treatment was inferior to either of these, and two others produced very low yields. It was concluded that of the methods evaluated, none is superior to no treatment at all, and some are clearly detrimental to developingArtemiaembryos

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00566.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

AbstractGrowth of juvenile Florida red tilapin (1.57 g average weight) spawned and sex‐reversed (monosex male) at salinities of 4 ppt and 18 ppt was compared at rearing salinities of 18 ppt and 36 ppt in 200 L aquaria under controlled photoperiod (12 L:12 D) and temperature (28 C). Growth was significantly higher for progeny spawned at 18 ppt than those spawned at 4 ppt under both rearing salinities with no difference observed between 18 ppt and 36 ppt.In another experiment, growth of juvenile progeny (0.98 g average weight) spawned and sex‐reversed at salinities of 2 ppt and 18 ppt was compared in 24 m3outdoor pools at 36 ppt. When water temperatures exceeded 27 C, growth and survival were not significantly different between these groups. However, when temperatures fell below 25 C, growth and survival were significantly higher among progeny spawned at 18 ppt.The results showed that progeny spawned and reared through early ontqenetic development in brackishwater are better adapted for growth in brackish and seawater and suggested that these fish may have higher resistance to cold‐stress in seawater than progeny spawned in fresh

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00567.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

AbstractA protected form of vitamin C, L‐ascorbyl‐2‐poly phosphate (APP), was tested for safety and efficacy in fishes. Phosphorylation of the 2‐hydroxyl group protected the 2,3‐enediol of L‐ascorbic acid against oxidation. When APP was added to feed, about 15% of its vitamin C activity was lost during milling and storing 5–7 d at ambient temperature. Stability of APP in pelleted feeds at 25 or 40 C was up to 83 times or 45 times greater than that of ascorbic acid (AA), respectively. In later tests, trout feed mash, steam‐pelleted in triplicate, frozen, and shipped on dry ice before analysis, had 46% loss of AA and no apparent loss of APP.With 16% milling loss (highest detected in trout feeds assayed in initial tests) and 22% storage loss after 90 d, conservative APP mix rates were estimated. Mixing 153 g L‐ascorbate‐equivalent as APP per metric ton of airdry ingredients (153 ppm) would give 128 ppm in the finished feed after steam‐pelleting and 100 ppm after 60–90 d storage at 40 C.Low‐temperature extrusion of Oregon‐Moist salmon feed reduced AA slightly. Ascorbic acid oxidized in frozen storage and while thawing and, after 12 h at room temperature, only trace amounts remained. Ascorbyl‐2‐polyphosphate at 0.05 to 0.2 times that of equimolar AA in casein‐base or practical feeds supported long‐term growth and development in rainbow trout and other fishes. Trout feeding trials with practical feeds in actual production regimens documented APP activity at growth rates approaching the maximum for trout farming.Corrected for greater stability, APP antiscorbutic activity appeared to be comparable to that of AA on a molar‐equivalent basis. Similarly, apparent equimolar activity was inferred from estimated equilibrium levels of liver, kidney, and whole‐body AA and L‐ascorbyl‐2‐sulfate (AS) after prolonged APP use in trout feeds.Fathead minnow growth and reproduction in egg‐to‐egg life‐cycle tests also confirmed APP safety and efficacy as a stabilized source of vitamin C for feeds.None of the typical lesions of scoliosis, malformed gill lamellae, and crenulated opercles, nor conditions of poor health, anorexia, and eventual torpor seen in vitamin C‐deficient controls occurred in trout fed APP. No liver pathology was evident in trout fed APP for 252 d at 1.7 to 3.3 times the National Resear

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00568.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

AbstractProduction characteristics of channel catfish (Ictalurus punctatus) reared in cages and open ponds were compared. Fish reared in open ponds had significantly better growth and food conversion ratios than fish reared in cages. Cages and open ponds stocked with fish which were closely graded in size produced fish with less size variability at harvest compared to ponds and cages stocked with nongraded and coarsely graded fish. The decrease in size variability at harvest was reflected in a greater proportion of marketable fish.

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1989.tb00569.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY