bluuebunny/crossref_metadata_2025_split huggingface dataset:
Masculinization of Channel Catfish Ictalurus punctatus by Oral Administration of Trenbolone Acetate
Authors: Galvez John I. , Mazik Patricia M. , Phelps Ronald P. , Mulvaney Donald R. 
Published: April 2007

AbstractAll‐male populations of channel catfish, Ictalurus punelatus, were produced by feeding a diet containing trenbolone acetate to swim‐up fry for 60 d. This hormone was effective in producing 100% males at doses of 50 to 150 mg/kg of diet. Fish that received 0 or 1 mg/kg of diet did not differ from the expected 1:1 sex ratio. Survival of control fish and fish fed diets containing trenbolone acetate were similar (P > 0.05) at the end of the treatment period and after a 60‐d grow‐out period. Our results represent the first report of successful masculinization of channel catfish with a synthetic anabolic androgenic steroid.
Comparative Growth of Diploid and Triploid Asian Catfish Clarias macrocephalus in Thailand
Authors: Fast Arlo W. , Pewnim Thanit , Keawtabtim Rathaya , Saijit Rungarun , Te Franklin T. , Vejaratpimol Renu 
Published: April 2007

AbstractWild caught Asian catfish were spawned manually following HCG injection, and a portion of the eggs were subjected to cold‐shock at 4 C for 15 min within 2‐min post‐fertilization. Nuclear diameter measurements of cold‐shocked fish revealed that 96% were triploids (3N), while non‐shocked fish were all diploids (2N). During larval and fry culture (first 26 d), triploid fish mortality was =50%, while diploid mortality was =25%. Following 8‐mo culture in tanks at three stocking densities, triploid fish survival was significantly greater (P < 0.05), than diploids, with 84.0% and 57.3%, respectively. Triploid live weight was also significantly greater than diploids, with 69.2 and 45.9 g averages, respectively. Ninety‐two percent of diploids had welldeveloped gonads after 8 mo; whereas none of the triploids had mature gonads. Gonads were undifferentiated with 31% of the triploids. These sexually undifferentiated fish had greater growth rates than male or female triploids, and greater growth than all diploids. Carcass weight (gutted) of triploids was 95.8% of live weight, compared with 92.5% for diploids. Lastly, triploids had very few deformities compared with diploids, with 1.3% and 17.6%, respectively. Deformities included curved spines, and humped backs just posterior of the head.
Effects of Feed Application Rates on Growth, Survival, and Feed Conversion of Juvenile Snakehead Channa striatus
Authors: Qin Jianguang , Fast Arlo W. 
Published: April 2007

AbstractGrowth, survival and feed conversion ratio of juvenile snakehead Channa striatus were evaluated when fed a dry, formulated feed (50% crude protein) at 24 ± 1 C. Six daily feed application rates were used (0%, 5%, 10%, 15%, 20%, and 30%), as a percentage of fish body weight, with three replicates per treatment. After 29 d, final weights were all significantly greater (P < 0.01) than initial weights, except for the 0% application. Feed applications higher than 5% did not result in increased growth (P > 0.05). Feed conversion ratio was 0.99 at 5% feed application, and 6.3 at 30% feed application. Fish survival was increased by providing formulated diet, but no further improvement was found when feed applications exceeded 5%. Cannibalism was reduced by providing formulated feed, but it was unavoidable when substantial differences in fish size existed, even when feeding ad libitum. Our results indicate that the optimal feed application rate is close to 5% body weight/d for juvenile snakehead.
The Effects of Substituting Selected Oilseed Protein Concentrates for Fish Meal in Rainbow Trout Oncorhynchus mykiss Diets
Authors: Stickney Robert R. , Hardy Ronald W. , Koch Kim , Harrold Robert , Seawright Damon , Massee Kenneth C. 
Published: April 2007

AbstractThree oilseed protein concentrates (soybean, canola, and sunflower) were evaluated to determine their potential, when supplemented with deficient essential amino acids, to partially or completely replace fish meal in diets fed to rainbow trout Oncorhynchus mykiss. Triplicate aquaria of juvenile trout (average weight of 12 g) were fed the experimental diets for 10 wk, at which time the average weight of the fish was approximately sixfold higher than the initial weight. Average fish weight gains on diets in which the protein component was 100% fish meal; 75% fish meal, 25% soybean protein concentrate; 50% fish meal, 50% soybean protein concentrate; and 75% fish meal, 25% sunflowerseed protein concentrate were not significantly different (P < 0.05). The average weight of fish fed a commercial feed was significantly lower than that of fish fed the 100% fish meal diet, but not significantly different from fish fed the three other formulations mentioned above. Fish fed diets containing 50% fish meal, 50% canola protein concentrate; and 25% fish meal, 75% sunflowerseed protein concentrate had significantly lower average final weights than those of fish fed the other diets. Feed conversion ratio patterns among the dietary treatment groups reflected those of weight gain. Fish survival exceeded 95% on all diets. Apparent protein digestibility coefficients ranged from 79.5% (75% soybean protein concentrate, 25% canola protein concentrate) to 90.6% (100% soybean protein concentrate). The results of this study demonstrated that certain oilseed protein concentrates have good potential as protein sources in rainbow trout feeds when properly supplemented with essential amino acids.
Iron Methionine and Iron Sulfate as Sources of Dietary Iron for Channel Catfish Ictalurus punctatus
Authors: Lim Chhorn , Sealey W. M. , Klesius P. H. 
Published: April 2007

AbstractThe dietary iron requirement for normal growth and optimum hematological values and bioavailability was determined for channel catfish Ictalurus punctatus fingerlings using egg‐white based diets supplemented with 0,5,10,20,60, and 180‐mg iron/kg from iron methionine or 20, 60, and 180‐mg iron/kg from iron sulfate. The basal diet which contained 9.2‐mg iron/kg, 34% crude protein and 3.1 kcal of digestible energy/g was fed to channel catfish fingerlings (8.5 g) in triplicate flow‐through aquariums to satiation twice daily for 8 wk. Fish fed the basal diet without iron supplementation exhibited poor growth throughout the 8‐wk period. Fish fed iron‐supplemented diets did not differ with regard to final weight gain. Survival, feed conversion, total blood cell count, mean corpuscular hemoglobin concentration, serum iron, total iron binding capacity, and transferrin saturation were not significantly affected by dietary iron level. Hemoglobin, hematocrit, mean corpuscular hemoglobin, and mean corpuscular volume were significantly lower in fish fed the basal diet. These values were also consistently lower for fish fed diets with 5 and 10‐mg iron/kg from iron methionine. However, differences were not always significant. Results of this study indicate that supplementation of 5‐mg iron from iron methionine was sufficient for growth. However, a supplemental iron level of 20‐mg/kg diet or a total iron level of 30‐mg/kg of diet appeared to be needed for optimum hematological values. Iron methionine and iron sulfate were equally effective in preventing anemia in channel catfish.
Timing of Supplemental Feeding for Tilapia Production
Authors: Diana James S. , Lin C. Kwei , Yi Yang 
Published: April 2007

AbstractThe staged addition of feed to fertilized fish ponds was evaluated by adding fertilizers to 15 ponds stocked with Nile tilapia Oreochromis niloticus, then adding feed at half ad libitum rates once fish in the ponds reached a target weight. Each pond was stocked with 750 fish (3 fish/m2), and each treatment included three ponds with first feeding at (a) 50 g, (b) 100 g, (c) 150 g, (d) 200 g, and (e) 250 g. Ponds in Thailand (at the Ayutthaya Freshwater Fisheries Station, Royal Thai Department of Fisheries) were maintained for 236–328 d until the fish reached 500 g.Growth was similar for all treatments under fertilizer alone (1.17 g/d) and was also similar when feed was applied (3.1 g/d). Feed application rates averaged 1.17% BW/d, indicating substantial use of natural food. Pond water quality did not deteriorate under supplemental feeding. Feed conversion rates averaged 1.03. Multiple regression indicated that 73.8% of the variance in growth was explained by design variables (feed input and days), while 86.2% of the variance in growth was explained by adding dissolved oxygen content and alkalinity into the equation.The most efficient system was to grow fish to 100–150 g with fertilizers alone, then add feed. First adding feed (at 50% ad libitum) once fish reached 100 g produced the highest predicted annual revenues ($6,164 per hectare). Results of this experiment indicated that either critical standing crop occurred early (before the first fish sample) or did not occur at all in these ponds.
The Effect of Temperature on Production of Gonads by the Sea Urchin Strongylocentrotus franciscanus Fed Natural and Prepared Diets
Authors: McBride Susan C. , Pinnix William D. , Lawrence John M. , Lawrence Addison L. , Mulligan Timothy M. 
Published: April 2007

Abstract Strongylocentrotus franciscanus (248 ± 76 g wet body weight, mean and standard deviation) were maintained in the laboratory at 12.9 and 16.1 C and fed either Nereocystis luetkeana or a prepared feed for 4 mo (July through October). The size and histological condition of the gonads of an initial sample, the experimental animals, and a sample from the commercial fishery were evaluated. The gonad index of experimental S. franciscanus increased from an initial 3.4%± 1.4 to 19.2%± 3.3 (mean and standard deviation) for the four treatments. The feeding rate was greater for individuals fed N. luetkeana and for both foods at the higher temperature. Gonad production was not significantly different among the experimental treatments, indicating the prepared feed was nutritionally superior to the algal diet and an increase in catabolism at the higher temperature balanced the increase in food intake. Histological preparations determined the urchin gonads developed from an initial spent condition to the premature stage for both experimental and fishery samples, indicating neither food or temperature affected gametogenesis.
Net Absorption of Dietary Phosphorus from Various Inorganic Sources and Effect of Fungal Phytase on Net Absorption of Plant Phosphorus by Channel Catfish Ictalurus punctatus
Authors: Eya Jonathan C. , Lovell Richard T 
Published: April 2007

AbstractYear‐2 channel catfish (average weight 765 g) were fed a commercial‐type, all‐plant diet containing supplemental phosphorus (0.40%) from one of various sources, or fungal phytase (1,000 and 3,000 units), in 1‐m3 circular raceways for 21 d at a temperature of 28–30 C. Subsequently, net absorption of phosphorus from the diets was determined by the chromic oxide indicator method in which feces were collected from the rectum. Net absorption of the supplemental phosphorus was corrected for the absorbed residual phosphorus in the basal diet. Net absorption coefficients for monosodium phosphate, monoammonium phosphate, finely ground defluorinated rock phosphate and monocalcium phosphate were 88.6, 85.4, 81.7, and 81.2%, respectively, and were not significantly different. Net absorption coefficient for dicalcium phosphate was significantly lower, 74.8%, but was significantly higher than those for coarsely ground defluorinated rock phosphate and tricalcium phosphate, which were 55.1 and 54.8%, respectively. These data are in general agreement with relative bioavailability values based on growth response for channel catfish determined in other research, and should be appropriate for determining available phosphorus allowances in commercial feeds and establishing phosphorus budgets in aquaculture feeding operations. The net absorption of phosphorus from the all‐plant basal diet was 31.2% and increased significantly to 55.1 and 62.5% with the addition of 1,000 and 3,000 units of fungal phytase, respectively.
Growth, Survival, and Biochemical Composition of Freshwater Prawns Macrobrachium rosenbergii Fed Natural Food Organisms Under Controlled Conditions
Authors: Tidwell James H. , Schulmeister Greg , Mahl Cathy , Coyle Shawn 
Published: April 2007

AbstractUnder production conditions freshwater prawns Macrobrachium rosenbergii are supplied nutrients by a combination of prepared diets and natural pond organisms. For maximum production efficiency and profitability it is important that the nutritional contributions of natural foods be identified and quantified. In this study the relative importance of forage organisms previously identified as important natural foods for prawns in ponds were evaluated under controlled conditions. Juvenile prawns (average weight 1.80 ± 0.06 g) were stocked into 18 37.5‐L aquaria at a density of 10 prawns per tank. The six dietary treatments tested were: 1) unfed (negative control); 2) commercially prepared diet (positive control); 3) oligo‐chaetes; 4) chironomids; 5) zooplankton; and 6) a combination of the latter three. Each treatment was evaluated in triplicate aquaria for 7 wk. The growth rate of prawns in the unfed treatment was statistically lower than in fed treatments (P < 0.05). There were no significant differences (P > 0.05) between growth rates and survivals among prawns in the five fed treatments. Selective retention of arachidonic acid (20:4n‐6), eicosapentanoic acid (22: 5n‐3), and docosahexanenoic acid (22:6n‐3) in unfed prawns likely indicates the relative nutritional importance of these fatty acids. Comparisons of whole‐body fatty acid and amino acid concentrations of prawns and food organisms indicate that zooplankton and oligochaetes may have the most appropriate biochemical compositions as prawn food sources.
Influence of the Dietary Level of Iron from Iron Methionine and Iron Sulfate on Immune Response and Resistance of Channel Catfish to Edwardsiella ictaluri
Authors: Sealey Wendy M. , Lim Chhorn , Klesius P. H. 
Published: April 2007

AbstractChannel catfish Ictalurus punctatus fingerlings were fed purified diets supplemented with iron at levels of 0, 20, 60, and 180 mg/kg from iron sulfate (FeS) or 5, 10, 20, 60, and 180 mg/kg from iron methionine (FeM) in triplicate tanks for 8 wk. Fish were then divided into two groups and subjected to different assays to measure disease resistance and individual immune functions. Representative fish from each dietary treatment were challenged by bacterial immersion with virulent Edwardsiella ictaluri, and mortality due to enteric septicemia was recorded. Other fish were immunized with 0.2–mL formalin‐killed E. ictaluri and boosted 21 d post‐immunization. Antibody response was determined by FAST‐ELISA. Chemiluminescent and chemotaxis assays were performed using peritoneal macrophages. Supplementation of the diet with various levels of iron from FeS or FeM did not significantly affect antibody production. Chemotactic migration by macrophages was depressed in iron‐deficient fish and a level of 60 mgkg from either FeS or FeM provided the highest chemotactic indexes. A deficiency of dietary iron was found to increase mortality of channel caffish due to enteric septicemia of catfish (ESC). However, more studies should be conducted to better understand the effects of sources and levels of dietary iron on immune responses and disease resistance in channel caffish.
The Toxicity of Hydrogen Peroxide to Rainbow Trout Oncorhynchus mykiss and Cutthroat Trout Oncorhynchus clarki Fry and Fingerlings
Authors: Arndt Ronney E. , Wagner Eric J. 
Published: April 2007

AbstractFungal and parasitic infections of fish can significantly impact the survival of cultured fish. Formalin is currently used to control such infections; however, concern has arisen over its safety to users and to the environment. Hydrogen peroxide has been designated as a low priority fungicidal drug by the United States Food and Drug Administration (FDA), yet, little information is available on treatment concentrations or its toxicity to trout. Rainbow trout Oncorhynchus mykiss and cutthroat trout Oncorhynchus clarki fry and Angerlings were exposed to hydrogen peroxide concentrations of 0, 70, 170, 280, 420 and 540 ppm for 30, 60 or 120 rnin at 15 C to determine the chemical's toxicity. Rainbow trout fry and fingerlings experienced elevated mortalities (>20%) during treatments using 420 and 540 ppm for 30 min; 280, 420 and 540 ppm for 60 min; and >170 ppm for 120 min. Cutthroat trout fry experienced elevated mortalities (>23%) during treatments using 540 ppm for 30 min; 420 and 540 ppm for 60 min; and >170 ppm for 120 min. Cutthroat trout fingerlings experienced elevated mortalities (>60%) during treatments using 540 ppm for 60 min and >280 ppm for 120 min. No control mortalities were encountered for both life stages of either species. The lethal concentrations (LC50) of both age classes and species for each of the three durations ranged from 514–636 ppm for 30 min treatments, 322–506 ppm for 60 min treatments, and 189–280 for 120 min treatments. Mortalities for all four toxicity tests which occurred during a 96‐h post‐treatment period were centered around the following treatments: 30 min, 540 ppm; 60 min, 280–540 ppm; 120 min, 170 ppm. Tissue damage to gills was found only among fish that did not survive the initial chemical exposure. Test concentrations proved to be relatively stable during a 24‐h period, retaining better than 85% of their original strength for all five dilutions. At a water temperature of 15 C concentrations should not exceed 280 ppm for a 30‐min treatment.
Enhancement of Gonad Production in the Sea Urchin Loxechinus albus in Chile Fed Extruded Feeds
Authors: Lawrence John M. , Olave Sergio , Otaiza Ricardo , Lawrence Addison L. , Bustos Eduardo 
Published: April 2007

Abstract Loxechinus albus were fed algae (Macrocystis pyrifera and Ulva sp.) and two feeds prepared by extrusion (one containing kelp). Results were the same for individuals maintained in suspended cages in the sea and in aquaria on land. Gonads increased in size in individuals fed extruded feeds and decreased in individuals fed algae during the spawning season. Gonads increased ca. four‐fold in size in individuals fed the extruded feeds during the post‐spawning season, much greater than those fed algae. Individuals fed extruded feeds had a lower feeding rate than individuals fed algae on a wet‐weight but not on a dry‐weight basis. The extruded feed supports gonadal growth more than natural food and has potential for use for aquaculture of sea urchins.
Effects of Stocking Density and Monosex Culture of Freshwater Prawn Macrobrachium rosenbergii on Growth and Production in Concrete Tanks in Saudi Arabia
Authors: Siddiqui Abdul Qayyum , Al‐Hafedh Yousef S. , Al‐Harbi Ahmed H. , Ali Seikh A. 
Published: April 2007

Abstract This study was conducted to evaluate the effects of stocking density and monosex culture on growth, survival, yield and feed conversion ratio of freshwater prawn Macrobrachium rosenbergii in concrete tanks. Juvenile prawns with an average weight of 1.8 g were stocked into triplicate tanks at densities of 5, 10, 15 and 20 prawns/m2, grown for 168 d and fed a 34% tilapia diet. Stocking density had significant effect on prawns. Final mean body weight decreased with the increasing density, being highest at 5 prawns/m2 (29.6 9). and lowest at 20 prawns/m2 (17.4 g). Total yield increased from 135 g/m2 (1,350 kg/ha) at a density of 5 prawns/m2 to 261 g/m2 (2,610 kg/ha) at density 15/mz to 245 g/m2 (2,450 kg/ha) at 20/mz. Feed conversion ratios were high and ranged from 3.7 (5 prawns/m2) to 5.6 (20 prawns/m2).In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m2 for 112 d, the all‐male population had the best growth performance and feed conversion ratio, followed by the mixed‐sex and all‐female populations. The all‐male population had 99% marketable prawns (>20 g) with an average yield of 159 g/m2 (1,590 kg/ha); the mixed‐sex population had 90% marketable prawns and the yield was 135 g/mz (1,350 kg/ha); and the all‐female population had 75% marketable prawns with an average yield of 108 g/m2 (1,080 kgha).
Optimal Dietary Protein Concentration for Hybrid Tilapia Oreochromis niloticus × O. aureus Fed All‐Plant Diets
Authors: Twibell Ronald G. , Brown Paul B. 
Published: April 2007

Abstract.There are several estimates of the optimal dietary crude protein concentration for juvenile tilapia fed high quality animal proteins or mixtures of animal and plant derived feedstuffs. In the present study, the optimal dietary crude protein concentration for hybrid tilapia Oreochromis niloticus × O. aureus reared in glass aquaria was determined using diets free of fish meal. Further, initial weight of fish was approximately 21 g, which is the beginning of the growout phase of many commercial operations. The diets contained primarily corn co‐products and soybean meal as the sources of amino acids, and were formulated to provide 24, 26, 28, 30, 32 or 34% crude protein. The diets were fed to quadruplicate groups of tilapia for 10 wk. Increasing concentrations of dietary crude protein resulted in proportional improvements in weight gain and feed efficiency up to 30% dietary crude protein. Fish fed 24% dietary crude protein exhibited significantly reduced weight gain compared to fish fed 28–34% dietary crude protein. Protein efficiency ratio (PER) of tilapia was unaffected by dietary crude protein concentration. However, fish fed 28% crude protein exhibited numerically higher PER (2.58) than fish fed other levels of crude protein. Muscle crude protein levels were lower in fish fed diets containing 24–28% crude protein than in fish fed 30% and higher concentrations. Quadratic regression analyses of weight gain and feed efficiency data indicated the optimal dietary crude protein concentration to be 29.65% and 28.33%, respectively, while broken line analyses indicated 27.5 and 27.3%, respectively. Based on weight gain, feed efficiency, PER, and proximate composition data, the authors recommend 28% dietary crude protein as the minimum for hybrid tilapia fed all‐plant diets and reared in tanks.
Coliform Organisms in Waters of Channel Catfish Ponds
Authors: Boyd Claude E. , Tanner Margaret 
Published: April 2007

Abstract.Water from 48 channel catfish Ictalurus punctatus ponds at Auburn and Greensboro, Alabama, USA, usually contained less than 1,000 total coliform and 200 fecal coliform bacteria per 100 mL. There were no sources of human fecal matter to ponds. Also, the fecal coliform: fecal streptococci ratio was less than 1.0 and typical of fecal contamination by warm‐blooded animals other than humans. The abundance of coliforms was greater in spring and summer than in fall and winter in catfish ponds and sportfish ponds at Auburn, Alabama. In spite of high organic matter inputs in feed, catfish ponds had no greater abundance of coliforms than sportfish ponds.