bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance of Post‐juvenile Rainbow Trout Oncorhynchus mykiss Fed Diets Manufactured by Different Processing Techniques
Authors: Schwertner Margaret A. , Liu Kenneth K. M. , Barrows Frederic T. , Hardy Ronald W. , Dong Faye M. 
Published: April 2007

AbstractFour different methods of pelleting—extruded (EXT), steam pelleted (STM), using a Universal Pellet Cooker (UPC), and expanded (EXP)—were performed on subsamples of a single batch of mash to determine the effects on feed pellet characteristics, in vivo feed digestibility, and performance of rainbow trout Oncorhynchus mykiss fed the diets for 16 wk. Results indicated that the STM feed was the most (851 g/L) and UPC feed the least (672 g/L) dense, and that UPC feed had the highest % float (8.3%) and, of the pellets that sank, the fastest sink rate (15.1 cm/sec). While some differences occurred among pelleted diets in loss of dry matter (% dry loss) after incubation in a water bath for up to 10 min, the overall % dry loss was only approximately 1–2%. The method of pelleting did not affect fish weight gain, feed conversion ratio, or specific growth rate. Measurement of the apparent digestibility coefficient of dry matter of the test diets using Cr2O3 as the marker ranged from 71–89%. While it appeared that the method of pelleting can affect feed characteristics and the amount of feed offered to the fish, fish performance was not affected.
Effect of Water Temperature on Growth, Survival, and Biochemical Composition of Largemouth Bass Micropterus salmoides
Authors: Tidwell James H. , Coyle Shawn D. , Bright Leigh Anne , Van Arnum Aaron , Yasharian David 
Published: April 2007

AbstractThe effects of water temperature on growth rate, survival, and biochemical composition of juvenile largemouth bass Micropterus salmoides were evaluated under controlled conditions in tanks for 12 wk. Feed‐trained juvenile largemouth (9.1 ± 1.9 g) were stocked into nine 3,610‐L polyethylene tanks inside a greenhouse structure at 140 fish/m3 (500 fish/tank). Three treatment temperatures were evaluated (20, 26, and 32 C) with three replicates per treatment. Bass were fed to apparent satiation twice daily using a commercially available floating salmonid diet (45% crude protein and 16% lipid). After 97 d bass grown at 26 and 32 C had significantly higher (P < 0.05) average weights, SGR, condition factor (K), and production rates (kg/m3) than those in the 20 C treatment. Bass in the 26 C treatment had significantly lower (P 0.05) FCR and higher percent protein deposit (PPD) than bass raised at 20 and 32 C, which were not significantly different (P >0.05). There were no significant differences (P >0.05) in survival among treatments which averaged 97%, overall. Bass raised at 32 C had higher (P 0.05) lipid levels in the liver than other treatments. Whole body amino acid concentrations were not significantly impacted (P >0.05) by culture temperature. Largemouth bass raised at 26 C had significantly lower (P 0.05) levels of stearic acid (18:0) and significantly higher (P 0.05) levels of arachidonic acid (20:4 n‐6) than bass raised at 20 or 32 C. Bass raised at 32 C had significantly higher (P 0.05) levels of Linoleic acid (18:2 n‐6), total saturates, and dienes than bass raised at 26 or 20 C. These data indicate that growth and feed conversion efficiency are reduced at 20 C. Growth is similar at 26 and 32 C, but feed and dietary protein are more efficiently utilized at 26 C.
Growout of Freshwater Prawn Macrobrachium rosenbergii in Fertilized Ponds with Reduced Levels of Formulated Feed
Authors: Correia Eudes S. , Pereira José A. , Silva André P. , Horowitz Ami , Horowitz Sarah 
Published: April 2007

AbstractFormulated feed for freshwater prawn farming under semi‐intensive conditions is expensive, presenting a significant portion of the farm's operating costs. Production and availability of natural food in earthen ponds may reduce the needs for formulated feed. This paper evaluates growth of freshwater prawn Macrobrachiurn rosenbergii under three feeding regimes, where supplemental feed was reduced and natural productivity of the ponds was increased by a fertilization program that included the addition of lime, phosphorus and nitrogen. Prawns (4.35 g) were stocked into 12 50‐m2 earthen ponds (6 juveniles/m2) and grown for 84 d feeding on 25% crude protein ration. Chemical and physical water parameters were monitored routinely. Growth and production were similar at 100% formulated feed supplementation with no fertilization and at 50% formulated feed with fertilization, as determined by weight gain, specific growth rate, and net yield (P >0.05). However, further reduction in feed supplementation (0, 25%, and 50% of feeding rate, respectively, for each subsequent 28‐d period) with fertilization, yielded shrimp smaller than market size. Feed conversion ratios were significantly higher (P 0.05) for the 100% versus the 50% feed supplementation. Survival rate averaged 86% with no significant differences among treatments. Reducing up to 50% of the supplemental feed with added fertilization for increased natural productivity does not reduce yield of M. rosenbergii raised under semi‐intensive conditions in northeastern Brazil. Under the local conditions of semi‐arid and warm water temperatures (24.0–33.5 C), increasing natural productivity of ponds significantly improves feed conversion ratio, which is reflected in feed cost savings and potential savings of the farm operating cost.
Use of White Fat as a Replacement for Squid Liver Oil in Practical Diets for Surubim Pseudoplatystoma coruscans
Authors: Martino Ricardo C. , Trugo Lulz C. , Cyrino José Eurico P. , Portz Leandro 
Published: April 2007

AbstractThe effect of dietary lipid on culture performance, fatty acid composition of carcass, and the liver polar lipid of surubim fingerlings Pseudoplatystoma coruscans was investigated. Five isonitrogenous (46.5% crude protein) and isolipidic (19% crude lipid) diets were formulated with squid liver oil (SLO) and white fat (pig lard‐PL) as lipid sources. Diet 1 was supplemented with 12% SLO, diet 2 with 8% SLO and 4% PL, diet 3 with 6% SLO and 6% PL, diet 4 with 4% SLO and 8% PL, and diet 5 with 12% PL. Fish were fed to apparent satiation over a 64‐d feeding trial. No statistically significant difference (P >0.05) was observed in growth performance of fish. In contrast, fatty acid profile of fish carcass and liver polar lipid fraction was affected (P 0.05) by dietary fatty acid composition. Palmitic (16:O) and the oleic (18:1n‐9) acids were the major saturated and monoene fatty acids respectively found in fish carcass, independent of the lipid source in the diets. The total amount of saturated and monoene fatty acids was significantly higher (P 0.05) in the carcass of the fish fed diets 4 and 5, than in the other fish. The concentration (P 0.05) of eicosapentaenoic and docosahexaenoic acids and the n‐3/n‐6 ratio in fish carcass and in polar lipid fraction of liver increased in direct proportion to the level of squid liver oil in diet. Results of this experiment clearly demonstrated that both squid liver oil and pig lard have a positive nutritive value for surubim and that it is possible to increase the n‐3 to n‐6 ratio in favor of n‐3, without loss in the growth performance, feeding fish with a diet containing a lipid source rich in this fatty acid.
Tissue Residues of Diuron in Channel Catfish Ictalurus punctatus Exposed to the Algicide in Consecutive Years
Authors: Tucker Craig S. , Kingsbury Susan K. , Ingram Reba L. 
Published: April 2007

AbstractIn 1999, the United States Environmental Protection Agency granted an emergency exemption under Section 18 of the Federal Insecticide, Fungicide. and Rodenticide Act authorizing the use of the algicide diuron [3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea] to manage cyanobacterial off‐flavors in channel catfish Ictalurus punctcatus. Catfish may remain in ponds for more than one growing season and may therefore be exposed to more than one set of diuron treatments. This study was conducted to determine whether diuron residues in fish carry over from one year to the next and, if so, whether the cumulative exposure causes residues to exceed the tolerance level of 2.0 mg/kg in fillets. Catfish in earthen ponds were exposed to the label‐specified treatment protocol of nine consecutive weekly applications of diuron at 0.01 mg/L in the fall of one year and again the following spring. Diuron concentrations in fillets were below limits of detection (0.05 mg/kg) in all fish (N = 18) prior to the initial diuron treatment series. Immediately after the ninth weekly diuron application in the fall. tissue diuron levels averaged 0.353 mg/kg (pooled SEM = 0.036; range = 0.078–0.724 mg/kg; N= 18). On the day before the second set of diuron treatments 6 mo later. diuron concentrations were below limits of detection in all fish sampled. Immediately after the second set of nine weekly diuron applications, tissue concentrations averaged 0.127 mg/kg (pooled SEM = 0.015; range = not detected to 0.191 mg/kg; N = 18). This study showed that diuron residues in channel catfish were depleted within 2 to 4 mo after exposure to the chemical and there was no carryover of residues in fish from one year to the next. Maximum residue levels in catfish fillets were less than half the tolerance level of 2.0 mg/ kg.
Dietary Lipid Utilization by Juvenile Summer Flounder Paralichthys dentatus
Authors: Gaylord T. Gibson , Schwarz Michael H. , Davitt Gina M. , Cool Ryan W. , Jahncke Michael L. , Craig Steven R. 
Published: April 2007

AbstractThe ability of juvenile summer flounder Paralichthys dentatus to utilize dietary lipid as energy, and the effect of dietary lipid on weight gain and body composition was investigated in a 12‐week feeding trial. Diets were formulated to provide 55% crude protein from herring meal and casein. Menhaden oil was added to produce diets with 8, 12, 16 or 20% total lipid while providing 16.0 kJ available energy/g dry diet. The diet containing 20% total lipid supplied 16.7 kJ available energy/g dry diet due to the high levels of protein and lipid. An additional diet was included to reproduce currently available commercial diet formulations for flounder, providing 55% crude protein supplied solely from herring meal and 16% total dietary lipid. Juvenile summer flounder (initial weight 23 g) were stocked into triplicate aquaria in a closed, recirculating system maintained at 20 C. Fish were fed 2% of body weight each day divided into two equal feedings. Upon termination of the study, effects of dietary lipid on weight gain, body condition indices, and proximate composition were determined. Weight gain (96–149% of initial weight), feed efficiency ratio values (0.43–0.48). fillet yield, and whole‐body composition all were unaffected by dietary lipid level. High levels of dietary lipid did increase the lipid content in the finray muscle, as fish fed diets containing 16 and 20% dietary lipid had significantly higher lipid levels than fish fed the diet containing 8% lipid. No apparent protein sparing effect of lipid was observed. These data indicate that currently available commercial feeds for summer flounder may be over‐formulated and show a need for further research to determine specific and accurate nutritional information for this species.
Toward the Genetic Improvement of Feed Conversion Efficiency in Fish
Authors: Doupé Robert G. , Lymbery Alan J. 
Published: April 2007

AbstractFeed conversion efficiency (FCE) is the effectiveness with which feed is converted to saleable fish product. Feed costs are a major input to aquaculture production systems, and genetic improvement in FCE may therefore have an important influence on profitability. FCE is usually expressed by a composite measure that combines feed intake and growth rate. The two most common measures are feed conversion ratio (feed intake/weight gain over a specified time interval) and its inverse, feed efficiency. Feed conversion ratio and feed efficiency are measures of gross FCE, because they do not distinguish between the separate energy requirements of growth and maintenance. There is abundant evidence of substantial genetic variation in FCE and its component traits in terrestrial livestock species and, although data are few, the same is likely for cultured fish species. The major problems with selecting from this variation to genetically improve FCE in fish species are:It appears impractical to measure feed intake on individual fish, so that family mean data must be used.We do not know the optimal time period over which to test fish for FCE.We do not know the genetic correlations between FCE under apparent satiation or restricted intake conditions, or between FCE at different times in the production cycle.If these problems can be overcome, selection to improve FCE might be best achieved by measuring feed intake of growing animals, and by utilizing genetic correlations that are likely to exist between feed intake and other production traits to develop a weighted selection index.
Volitional Spawning of Black Sea Bass Centropristis striata Induced with Pelleted Luteinizing Hormone Releasing Hormone‐Analogue
Authors: Watanabe Wade O. , Smith Theodore I.J. , Berlinsky David L. , Woolridge Christopher A. , Stuart Kevin R. , Copeland Kimberly A. , Denson Michael R. 
Published: April 2007

AbstractThe black sea bass is a high‐value marine serranid and is a prime candidate for intensive cultivation. Reliable methods for controlled spawning are needed to accelerate the development of hatchery technologies that result in mass production of healthy juveniles. During 1998–2001, spawning studies were conducted at The University of North Carolina at Wilmington (UNCW) and at the South Carolina Department of Natural Resources (SCDNR), Charleston, using pelleted luteinizing hormone releasing hormone analogue (LHRH‐a).From April through July 2001, 28 vitellogenic‐stage females, with mean oocyte diameters (MOD) ranging from 277–448 μm, were implanted with a 95% cholesterol‐5% cellulose pellet containing LHRH‐a (‐50 μg/kg body wt) at UNCW. In 10 individual spawning trials, females with MOD of 305–448 μm and maximum oocyte diameter × 475 μm spawned volitionally beginning 2–3 d post‐implantation (PI) and continued spawning over an average of 1.9 d (range = 1–4 d). Individual females released a mean total of 149,000 eggs (117,000 eggs/kg) with a mean buoyancy rate of 40.5% (floaters). Fertilization and hatching rates were 98% and 27.2% of floaters, respectively, yielding 14,600 yolksac larvae/female (12,600 yolksac larvae/kg body wt), and overall egg viability averaged 8.9%. In eight group spawning trials (2–3 females/group), average performance of females, including fecundity (103,800 eggs/female; 105,500 eggs/kg body wt), buoyancy rate (42.5%), fertilization and hatching rates (97.7% and 24.3% of floaters), numbers of yolksac larvae produced (10,900 yolksac larvae/female; 10,100 yolksac larvae/kg body wt), and overall egg viability (10.6%) was comparable to what was seen in individual spawning trials.From 1998–2000, a total of 58 vitellogenic stage (70% of oocytes 500 pm) females were implanted with pelleted LHRH‐a (‐50 μg/kg body wt) in nine group spawning trials (2–19 females/group) at SCDNR. Volitional spawning typically began 18–42 h PI and recurred every 1–3 d for an average duration of 9 d. Female groups released a mean of 560,000 eggs (84,000/female; 132,000/kg body wt) over the spawning period, with mean buoyancy rate of 25.7% floaters. Fertilization and hatching rates were 17.7% and 11.6 % of floaters, respectively, yielding 4,300 yolksac larvae/female (4,600 yolksac larvae/kg body wt). Overall egg viability was 2.9%.Captive wild‐caught black sea bass were induced to undergo repetitive volitional spawning by implantation of pelleted‐LHRH‐a, consistent with a multiple clutch group synchronous pattern of ovarian development. Group spawning appears to be a practical way to compensate for variable fecundity and egg viability of individual females. Research is needed to identify optimum hormone treatments and eligibility requirements.
Lipid Nutrition and Feeding of Cobia Rachycentron canadum Larvae
Authors: Faulk Cynthia K. , Holt G. Joan 
Published: April 2007

AbstractThis study examined the fatty acid composition of cobia Rachycentron canadum eggs and yolksac larvae, as well as the ovaries of wild caught females as an initial guide to lipid nutritional requirements. A 2‐wk feeding study also was conducted to investigate the effectiveness of four dietary treatments on the growth and survival of cobia larvae. Cobia eggs in the tailbud stage contained 31.4 ± 1.3 μg lipid/egg. After hatching, the amount of lipid decreased significantly (P < 0.05) from 28.3 ± 0.3 to 23.2 ± 0.1 μg lipid/larvae during the yolksac larval stage (days 1 to 3 after hatching). Ovaries from wild caught adults and captive spawned eggs and yolksac larvae contained high levels of PUFAs with docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and arachidonic acid (ARA) accounting for approximately 80% of the total suggesting that cobia larvae may have a high dietary requirement for these fatty acids. For the feeding study, larvae were fed: 1) Artemia only; 2) enriched rotifers for 1 d only + microparticulate diet (day 313); 3) enriched rotifers for 3 d (day 3–5) + Artemia (day 3–13); and 4) enriched rotifers for 6 d (day 3–8) + Artemia (day 3–13). Cobia larvae began feeding on rotifers 3 d after hatching and on newly hatched Artemia nauplii by the fifth day following the onset of exogenous feeding (day 7). On day 7, no differences in larval growth were found among larvae fed rotifers for 3 versus 6 d, whereas larvae fed only Artemia or rotifers for I d followed by microparticulate diet were significantly smaller (P < 0.05) and did not survive beyond day 9 and 13, respectively. The results of the feeding study indicate that cobia larvae require rotifers for a minimum of 4 d following the onset of exogenous feeding.
Evaluation of Experimental and Practical Diets for Bluegill Lepomis macrochirus and Hybrid Bluegill L. cyanellus × L. macrochirus
Authors: Twibell Ronald G. , Wilson Keith A. , Sanders Shawn , Brown Paul B. 
Published: April 2007

AbstractTwo experiments were conducted to identify appropriate experimental and practical diets for bluegill Lepomis macrochirus and hybrid bluegill L. cyanellus × L. macrochirus reared in aquaria. In the first study, four experimental diets and five commercial diets were evaluated in juvenile hybrid bluegill initially weighing 4.8 g/fish. The experimental diets contained casein (CAS), casein + gelatin (CAWGEL), casein + L‐arginine‐HCI (CAS/ARG), or casein + gelatin + crystalline amino acids (CAS/AA) as sources of crude protein. The commercial diets included three diets formulated to meet the nutritional requirements of rainbow trout Oncorhynchus mykiss and two diets formulated to meet the nutritional requirements of channel catfish Ictalurus punctatus. Each diet was fed twice daily at a rate of 4% of body weigh/d to triplicate groups of fish. At the end of the 8‐wk feeding trial, weight gain was significantly higher in fish fed the best commercial rainbow trout diets (205–217%) compared to fish fed diets formulated for channel catfish (87–104%). Weight gain and feed efficiency (FE) of fish fed the experimental diets (5346% and 0.19–0.32, respectively) were significantly lower than those of fish fed the commercial rainbow trout diets (143–217% and 0.49–0.64, respectively). In the second experiment, the same dietary treatments were fed for 8 wk to juvenile bluegill initially weighing 3.7 g/fish. Each diet was fed twice daily at a rate of 4% of body weight/d to triplicate groups of fish. Weight gain was significantly higher in fish fed commercial trout diets (291–402%) compared to fish fed diets formulated for channel catfish (164–191%). Weight gain and FE of fish fed CAS/ARG were significantly higher than those of fish fed the commercial catfish diets, but significantly lower than those of fish fed the best commercial trout diets. Results of this study indicate that commercial rainbow trout diets are preferable to commercial channel catfish diets for culture of bluegill and hybrid bluegill. More research is needed to identify appropriate experimental diets for this group of fishes.
Incorporating Date Pits Phoenix dactylifera and their Sprouts in Semi‐purified Diets for Nile Tilapia Oreochromis niloticus (L.)
Authors: Belal Ibrahim E. H. , Al‐ Owafeir M. A. 
Published: April 2007

AbstractThe expansion in date processing has produced a large quantity of date pits Phoenix dactylifera L.: var. ruzeiz that could be used in animal feeds. To evaluate the nutritional value of date pits and their sprouts, two growth trials were conducted using semi‐purified diets and fingerling tilapia Oreochromis niloticus (L.). In the first trial, four isocaloric‐isonitrogenous diets containing different levels (0, 15, 30, and 45%) of date pits as a replacement for corn starch were fed to three replicate groups of fingerlings with a mean initial weight of 3.09 ± 0.10 g/fish. At the conclusion of the 9‐wk growth trial, final weight gain, feed conversion, specific growth rate and PER were significantly reduced in fish fed diets with all levels of date pits as compared to those fed the control diet (without date pits). However, there were no significant differences in these parameters for fish fed diets contained 15%, 30%, or 45% date pits. Body crude fat was gradually reduced as the level of date pits in the test diets was increased. Consequently, body moisture, crude protein and total ash were proportionally increased. In second trial, three isocaloric‐isonitrogenous diets containing 0% date pits (control diet), 15% date pits sprouted for 15 d, and 15% date pits sprouted for 30 d were fed to triplicate groups of tilapia with mean initial weight 2.60 t 0.09 g/ fish) for 9 wk. Growth rates and body composition of fish fed diets containing date pits that were sprouted for 15 or 30 d were similar to that of those fed the control diet. Under the reported conditions the inclusion of sprouted date pits did not affect growth and body composition, whereas nonsprouted date pits negatively influenced fish performance.
Characteristics of Effluents from Central Arkansas Baitfish Ponds
Authors: Bodary Melinda J. , Stone Nathan , Lochmann Steve E. , Frimpong Emmanuel 
Published: April 2007

AbstractScientific information on baitfish effluents is important to provide a basis for the development of appropriate and cost‐effective management practices that minimize environmental impacts. Effluents from 10 commercial golden shiner Notemigonus crysoleucas ponds in central Arkansas were sampled December 2000 through June 2001. Grab samples of the first and last 10% of pond volume were collected during intentional draining events. Effluents were sampled as they exited pond drainpipes and at the ends of drainage ditches just prior to stream discharge. Concurrent receiving stream samples were collected upstream and downstream of the discharge point. Total nitrogen (TN), total phosphorus (TP), 5‐d biochemical oxygen demand (BODS), and total suspended solids (TSS) of each sample were measured. Mean whole effluent concentrations for the first 10% were 36 mg TSS/L, 9 mg/L BOD5, 2 mg TN/L, and 0.5 mg TP/L. The water quality of the first and last 10% of pond effluent were not significantly different (P < 0.05). Filtering effluents through a 5‐pm mesh screen did not significantly reduce nutrient concentrations. Serial fractionation of effluents resulted in small but significant decreases in TSS concentrations in samples filtered through the 10, 8, and 5‐μm meshes (P < 0.05). Effluent discharge through farm ditches generally did not improve effluent water quality. Effluents collected at ditch ends were significantly less than drainpipe samples in BOD, concentrations only (P < 0.05). Limited data on receiving stream water quality indicated that only TP concentrations were greater in pond effluents than in receiving streams. Overall, baitfish pond effluents are similar in composition to effluents of other phytoplankton‐based pond production systems.