bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Satiate and Restricted Feeding of Channel Catfish with Diets of Varying Protein Quality in Production Ponds
Authors: Munsiri Prasert , Lovell Richard T. 
Published: April 2007

AbstractA 2 × 3 factorial experiment was conducted using satiate and restricted feeding with 32% crude protein diets containing low, medium, and high quality protein. Protein quality in the experimental diets was varied primarily by substituting peanut meal and cottonseed meal for soybean meal. Percentages of lysine, the first‐limiting amino acid, were 1.14, 1.33, and 1.61 in the low, medium, and high quality protein diets respectively. Digestible energy concentration of the diets was 2.9 kcal/g. Channel catfish were grown from an average weight of 47 g to marketable size over a 15 wk period at a stocking density of 13,750 fish/ha in 400 m2 earthen ponds. Each treatment was replicated in three ponds. Fish in the satiation group were fed as much as they would consume each day for the 15 wk experimental period. Fish in the restricted group were fed as much as they would consume until the daily feed allowance reached 65 kg/ha, which was reached at approximately week 5 of the experiment, and thereafter, there was no further increase in feed allowance.There was no significant interaction between feeding regimen and dietary protein quality for weight gain or feed conversion. Weight gain and feed efficiency under both satiation and restricted feeding increased linearly as protein quality increased. Protein quality had no influence on protein efficiency ratio (PER) under satiate feeding but had a positive effect on PER under restricted feeding. Protein quality had a positive linear effect on dressing percentage under restricted feeding, but in those fish fed to satiation, dressing percentage only increased between the low and high quality protein treatments. Protein quality had a negative linear effect on muscle fat but had no effect on visceral fat under satiate or restricted feeding. These results indicate that channel catfish are sensitive to protein quality differences in practical feeds at both satiate and restricted feeding rates, and that reduction in protein quality reduces dressing yield and increases muscle fat in food size fish.
Seasonal Changes in Water Quality in Commercial Channel Catfish Ponds in Mississippi
Authors: Tucker Craig S. , van der Ploeg Martine 
Published: April 2007

AbstractSelected water quality variables were measured at monthly intervals for 1 yr in 10 commercial channel catfish ponds in northwest Mississippi. Temporal changes in most variables appeared to be related to seasonal periodicity of phytoplankton abundance. Phytoplankton standing crops and total organic matter were highest in summer months when primary production was favored by warm water temperatures, high solar irradiance, and large inputs of nutrients resulting from high summer fish feed allowances. As day length, water temperature, and feed inputs decreased in autumn and winter, phytoplankton abundance and organic matter concentrations decreased. Seasonal changes in total nitrogen and total phosphorus concentrations were similar to phytoplankton abundance because much of the total nitrogen and phosphorus was contained within phytoplankton cells. Contrasting to the seasonal trend for total nitrogen, concentrations of dissolved inorganic nitrogen were lowest in the summer and highest in the cooler months. Rapid assimilation by phytoplankton served to maintain relatively low concentrations of dissolved inorganic nitrogen during the summer despite highest nitrogen loading rates during that period. Low water temperatures and generally less favorable conditions for phytoplankton growth decreased rates of nitrogen assimilation in the winter and ammonia, nitrite, and nitrate accumulated. Soluble reactive phosphorus concentrations were low throughout the year because physico‐chemical processes, such as precipitation and adsorption to bottom muds acted to continually remove inorganic phosphorus from the water column.
Neutral Buoyancy Salinity of Pacific Halibut Hippoglossus stenolepis Eggs and Larvae
Authors: Liu Han Wu , Stickney Robert R. , Dickhoff Walton W. , McCaughran Donald A. 
Published: April 2007

AbstractSamples of halibut eggs in nature have led to theories that development occurs near the sea bed and, alternatively, well up in the water column. Resolution of the conflicting theories and information which should assist culturists in providing the proper environmental conditions for egg development and hatching were the subjects of this study. The neutral buoyancy salinity (NBS) of Pacific halibut eggs and larvae ranged between 29.8–34%. Eggs and larvae with higher NBS (> 35%) were usually abnormal or stressed. Thus, eggs found near the seabed may be nonviable.
On the Structure and Molt Controlling Function of the Y‐Organ in the Prawn Penaeus indicus
Authors: Vijayan K. , Mohamed Sunilkumar , Diwan Arvind D. 
Published: April 2007

AbstractThe morphological and histological structure of the Y‐organ of Penaeus indicus is described. The gland 1–2 × 0.3 mm (LXW) is located in between the mandibular and posterior dorsoventral muscle at the junction of prebranchial and branchial chambers. Histochemical tests were performed to determine the chemical nature of the Y‐organ cells. Significant changes in the size and tinctorial affinity of the Y‐organ cells were observed in relation to the molt cycle. Y‐organectomy experiments revealed that the onset of premolt development was inhibited, suggesting the presence of molt inducing factor in the Y‐organ.
Growth of the Pearl Oysters Pinctada mazatlanica and Pteria sterna in Different Culture Structures at La Paz Bay, Baja California Sur, México
Authors: Gaytan‐Mondragon Isabel , Caceres‐Martinez Carlos , Tobias‐Sanchez Marcos 
Published: April 2007

AbstractA growth study of Pinctada mazatlanica and Pteria sterna was conducted to explain the basic steps required for the development of a pearl culture program in México. Seed for both species was collected using onion bags filled with black polyethylene sheets (40 ± 80 cm) and 5 g of vexar filament. The spatfall was July‐August 1987 for P. mazatlanica and December 1987‐February 1988 for P. sterna. The seed (12.8 ± 1.2 and 13.0 ± 0.6 mm respectively) was placed in pearl‐nets for intermediate culture (to attain 30 mm height). Populations were subsequently divided into three groups, two groups at 10 m depth in lantern and pocket nets and a third placed over a submerged shelf at 10 m depth in plastic net cages. Growth in height, survival and temperature were monitored. After 22 mo P. mazatlanica showed no significant differences in growth between culture structures. Nevertheless, the survival obtained in cages (99%) was larger than that obtained in hanging structures (65%). After 18 mo of culture, significant differences (F = 5.199 P = 0.05) in growth were observed for P. sterna. Larger animals were found in pockets (106.6 ± 0.8 mm) followed by lanterns (104.0 ± 0.7 mm) and finally in cages (103.5 ± 0.6 mm). Survival in pockets was 99%, 84% in lanterns and 98% in cages. With the operation of the different culture structures used in this study, the bottom cage system seems optimal to begin a culture program to obtain pearl‐oysters for nucleus implantation.
Preliminary Observations on the Reproductive Physiology of Female Orangemouth Corvina in Captivity
Authors: Thomas Peter , Copeland Paul A. , Prentice John A. 
Published: April 2007

AbstractSeasonal changes In oocyte growth and plasma estradiol, testosterone, thyroid hormones and vitellogenin levels were monitored in three captive adult female orangemouth corvina Cynoscion xanthulus subjected to a condensed (8 mo) seasonal cycle of photoperiod and water temperature. Plasma concentrations of estradiol and testosterone began to rise when temperature increased to 28 C and photoperiod to 15 h light (midsummer conditions). This was accompanied by elevated circulating levels of vitellogenin and the appearance of vitellogenic oocytes (diameter > 100 μm). Estradiol concentrations and mean oocyte size increased concurrently during late summer conditions and were maximum during fall conditions, approximately 8 wk after the beginning of ovarian recrudescence. In contrast, plasma levels of thyroid hormones did not show any distinct seasonal changes. Gonadally recrudesced females contained several size classes of vitellogenic oocytes. Injection of these fish with a luteinizing hormone‐releasing hormone analog (LHRHa) caused maturation and spawning of the largest oocytes (mean diameter of follicles × 2500 μm). Another group of vitellogenic oocytes had been recruited into this size class by 2 wk after the end of spawning, which suggests that this species is capable of repeated spawning during the reproductive season. Injection of LHRHa resulted in increased plasma levels of gonadotropin and repeated spawning over several days. LHRHa‐induced final oocyte maturation, ovulation and spawning were preceded by increases in plasma levels of two teleostean maturation‐inducing steroids, 17α,20β, 21‐trihydroxy‐4‐pregnen‐3‐one (20β‐S) and 17α,20β‐dihydroxy‐4‐pregnen‐3‐one (17α,20β‐P4). The results provide preliminary evidence that oocyte growth is stimulated in orangemouth corvina subjected to an abbreviated seasonal cycle in captivity under midsummer photoperiod and temperature conditions and is associated with seasonal increases in plasma estradiol concentrations and vitellogenin production. However, the relative importance of 20β‐S versus 17α, 20β‐P4 in the control of final oocyte maturation in this species could not be determined from the results of the present study.
A Survey of Trout Fin Erosion, Water Quality, and Rearing Conditions at State Fish Hatcheries in Utah
Authors: Bosakowski Thomas , Wagner Eeric J. 
Published: April 2007

AbstractA total of 600 hatchery trout were examined for signs of fin erosion including rainbow trout Oncorhynchus mykiss, cutthroat trout O. clarki, brook trout Salvelinus fontinalis and brown trout Salmo trutta. A scoring system was used to evaluate erosion on all fins from 20 fish samples. Water quality and hatchery rearing variables were also determined for corresponding raceways or ponds. For rainbow trout groups (N= 24), stepwise multiple linear regression was used to interpret the relationship between fin erosion and the other variables. These fish groups averaged between 92 and 243 mm in total length and no significant correlation was observed between length and a fin erosion index (r = 0.045). The best‐fit regression model (adjusted R2= 0.689) suggested that fin erosion was correlated with lower alkalinities, unnatural bottom substrates (concrete or steel), higher unionized ammonia levels, and higher fish densities. Despite significant variation between hatcheries, fin condition was significantly better in rainbow trout than in cutthroat trout in three of four hatcheries containing both species and the same substrate. Fin erosion in rainbow trout occurred primarily on dorsal fins, followed in order of decreasing severity, by pectoral, caudal, anal, and ventral fins.
Toward Coordination and Funding of Long‐Term Genetic Improvement Programs for Striped and Hybrid Bass Morone sp.
Authors: Hallerman Eric M. 
Published: April 2007

AbstractThe productivity and profitability of striped and hybrid bass Morone sp. aquaculture would be enhanced by genetic improvement of cultured stocks. To date, genetic improvement of cultured bass stocks largely has been limited to interspecific hybridization and ploidy manipulation, techniques which are aimed at short‐term genetic gains. Upon domestication, long‐term improvement of striped or hybrid bass can be approached. Lines of striped bass and other Morone species can be selected for rapid growth, stress tolerance, disease resistance, combining ability, or other traits. Improved lines can be crossed to produce superior hybrids or crossbreds, or manipulated to produce superior triploid or transgenic stocks. Current breeding projects are limited in size, and coordination of breeding activities among groups would be advantageous. Faced with the likelihood of limited government funding, long‐term genetic improvement of Morone species might be supported by the industry through a fund receiving a small percentage of the proceeds from sales of cultured Morone products.
Pond Bottom Soil Respiration during Fallow and Culture Periods in Heavily‐Fertilized Tropical Fish Ponds
Authors: Boyd Claude E. , Teichert‐Coddington David 
Published: April 2007

AbstractBenthic respiration in two fish culture ponds at Comayagua, Honduras, was below 1g CO2/m2per day during culture periods. When ponds were drained for fish harvest, bottom soils were exposed to the air, and soil respiration rates as high as 10g CO2/m2per day were recorded. High rates of soil respiration following removal of saturated conditions declined as labile organic matter was consumed and soil moisture content declined. Laboratory studies showed that the moisture content greatest for soil respiration was near saturation, and either drying soils or completely saturating them drastically reduced respiration. Although soil respiration rates were much greater during the fallow period than during the culture period, more organic matter was decomposed during the culture period because it was much longer (5 months) than the fallow period (2 weeks).
Effects of Dietary Vitamin C on Maturation and Egg Quality of Cod Gadus morhua L.
Authors: Mangor‐Jensen Anders , Holm Jens Chr. , Rosenlund Grethe , Lie ØOsyvind , Sandnes Kjartan 
Published: April 2007

AbstractThe effects of dietary vitamin C on maturation and egg quality of cod Gadus morhua L. have been investigated. The broodstock groups were fed three different levels of vitamin C mixed into a commercial dry pellet. The experimental feeding started three months prior to the spawning season. Naturally spawned eggs were collected and analyzed with regard to viability, biochemical composition and physical characteristics. Differences in free amino acid profile, egg strength and neutral buoyancy were found, whereas no effects on vital parameters, such as fertilization rate and survival rate, were detected.
Vibriosis of Swimming Crab Portunus trituberculatus in Larviculture
Authors: Muroga Kiyokuni , Sszuik Kouji , Ishimaru Kkatswa , Nogami Kinya 
Published: April 2007

AbstractSince 1985, frequent mass mortalities due to a bacterial infection have occurred in zoeal larvae of swimming crab Portunus trituberculatus reared at the Tamano Station of the Japan Sea‐Farming Association. A bacterium was predominantly isolated from diseased larvae and was demonstrated by experimental infection to be the causative agent of the disease. Based on morphological, physiological, biochemical, serological and genetic characteristics of the pathogen, it was thought to be a new species and tentatively named Vibrio sp. Zoea. Challenge experiments with the bacterium in several aquatic animals indicate that Vibrio sp. Zoea appears to be a pathogen specific for crustaceans.
Effects of Size‐Grading on Variation and Growth in Channel Catfish Reared at Similar Densities
Authors: Carmichael Gary J. 
Published: April 2007

AbstractChannel catfish Ictalurus punctatus obtained from two spawns were size‐graded into four weight groups: large, mean = 92.4 g ± 0.9 SE; medium = 64.2 ± 0.5; small = 36.1 ± 0.5; and communal = 49.0 ± 2.0 (a combination of large, medium, and small fish). Twelve indoor 643 L rearing units were stocked with the four size‐graded groups at initial densities (but different numbers of fish) of 3.12 g offish per L water and were fed for 66 d at 3% of biomass daily. At harvest the final densities (mean = 9.95 g/L) were equal in all rearing units. Survival and feed conversion were similar among the size‐groups. Initial Coefficients of variation for weight were significantly different among the size‐graded group as large < medium < small < communal. Final coefficients of variations were significantly greater than initial values in the large, medium, and small size‐graded group and were less in the communal group. Gain, survival, and coefficient of variation relationship within the communally stocked rearing units were similar to those for separately reared groups. Final coefficients of variation were greater (210, 204, and 115%) or less (89%) than initial values for large, medium, small, and communal groups, respectively, and indicate a repnrtitioning of variation, perhaps due to altered feeding behavior or social hierarchical order.
Evaluation of Omega‐3 Fatty Acid Enrichment of Artemia Nauplii as Food for Striped Bass Morone saxatilis Walbaum Larvae
Authors: Oozkizlick Sureyya , Chu Fu‐Lin E. 
Published: April 2007

AbstractThree enrichment techniques were evaluated for their efficiency in improving the dietary value of Artemia nauplii to striped bass larvae. Newly hatched Artemia nauplii from the Great Salt Lake (GSL) were enriched for 24 h using the following diets: 1) gelatin‐acacia microcapsules containing menhaden oil rich in omega‐3 polyunsaturated fatty acids (PUFA), primarily 20:5ω3 eicosapen‐taenoic acid; 2) an emulsion of Baker's yeast and menhaden oil; and 3) marine Chlorella sp. Unfed San Francisco Bay (SFB) and GSL nauplii were used as controls. Enriched GSL (all three diets) and unfed SFB nauplii had significantly higher (P < 0.05) levels of 20:503 than the unfed nauplii from GSL. Seven days post‐hatched (day 0) striped bass larvae were reared for 21 d on enriched or unfed nauplii. On day 21, wet weight and total length of striped bass larvae fed enriched GSL nauplii and unfed SFB nauplii were significantly greater (P < 0.05) than those fed unenriched GSL nauplii. The enrichment of the GSL nauplii appeared to increase the eicosapentaenoic acid content and enhance the growth of the striped bass larvae.
Effects of Stocking Density and Feed on Pond Production Characteristics and Revenue of Harvested Freshwater Prawns Macrobrachiurn rosenbergii Stocked as Size‐Graded Juveniles1
Authors: Daniels William H. , Dabramo Louis R. , Fondren Mack W. , Durant Martin D. 
Published: April 2007

AbstractA nursery‐reared population of juvenile freshwater prawns (Macrobrachium rosenbergii) averaging 0.11 ± 0.058 g was size graded through a 4‐mm bar grader producing a numerically 53% upper size population (0.25 ± 0.086 g). These were stocked into triplicate earthen ponds (0.04–0.07 ha each) at densities of 39,540, 59,300 and 79,100/ha, grown for 131 to 134 d, and fed a specially formulated diet. An additional three ponds were stocked at 39,540/ha and fed a commercial sinking catfish feed. Density had a significant effect on average whole body wet weight at harvest but no significant effect on either total yield, survival, or feed conversion. Mean wet weight was significantly higher for prawns stocked at 39,540/ha (34.3 g) than that for those stocked at either 59,300/ha (26.7 g) or 79,100/ha (263 g). The direct relationship between the percentage of small males and increasing density usually seen with ungraded populations was not evidenced in the size‐graded populations. Average total yield ranged from 1,041 to 1,662 kg/ha for stocking densities from 39,540 to 79,100/ha. Differences in overall mean wet weight resulted from differences in mean wet weights for orange claw and no claw males and berried and open females, not from differences in morphotype distributions. These differences resulted in significantly higher percentages of tails within the larger count categories and higher revenues for prawns stocked at 39,540/ha. Feed type had no significant effect. Projected net revenues suggest that prawns need to be marketed and sold as a whole product.
Tolerance to Formalin by a Fluidized‐Bed Biofilter and Rainbow Trout Oncorhynchus mykiss in a Recirculating Culture System
Authors: Heinen John M. , Weber Amy L. , Noble Alicia C. , Morton Joseph D. 
Published: April 2007

AbstractFormalin tolerances of a fluidized‐bed sand biofilter and rainbow trout Oncorhynchus mykiss were tested in a semi‐closed freshwater recirculating culture system. Progressively higher formalin levels were tested until fish mortality (±1.9%) occurred. A 1‐h exposure to 167 ppm formalin, followed by flushing, was safe for trout (no mortality) at 15.0 C but not at 16.5 C. A 110‐ppm indefinite treatment (no flushing) was safe at 17.3 C, but 120 ppm at 17.3 C and 100 ppm at 17.8 C were not. Biofilter nitrification was not impaired by 1‐h formdin treatments up to 167 ppm at 16.5 C, and not, usually, by indefinite treatments up to 120 ppm at 17.3 C. However, a find indefinite treatment of 70 ppm was followed by abnormally high nitrite levels for 9 d. Formaldehyde remained detectable in the system for 11 h during indefinite treatment at 120 ppm formalin. Tests on the system's Co2 stripper did not indicate that it removed formaldehyde.
Effects of Water Temperature, Density, and Sex Ratio on the Spawning Rate of Red Claw Crayfish Cherax quadricarinatus (von Martens)
Authors: Yeh Hsin Sheng , Rouse David B. 
Published: April 2007

AbstractEffects of water temperature on red claw crayfish Cherax quadricarinatus spawning rates was evaluated for 3 mo at 22, 26 and 30 ± 1 C. A 20/m2 stocking density and a 1:2 M: F sex ratio was used. Spawning rate increased as temperature increased, with 30 C providing the highest spawning rate (P < 0.05). Effects of stocking density and sex ratio on the reproduction of red claw crayfish were also evaluated at densities of 10.15 and 20/m2, with a sex ratio of 1:1, and at three sex ratios (1:1. 1:3 and 1:5 M: F) at a density 10/m2. Water temperature was maintained at 28 ± 1 C and photoperiod was maintained at 14L: 10D for 6 mo during the density and sex ratio experiments. Spawning rates were not significantly different (P > 0.05) within the three stocking densities at a sex ratio of 1:1, nor were they different (P > 0.05) for the three sex ratios at a density of 10/m2. Results revenled that densities as high as 20/m2 and sex ratios of 1 male to 5 females can be used to increase spawning per tank. Also, high temperature (28 ± 1 C) and long day lengths (14L: 10D) can be utilized to stimulate peak spawning rates, but high spawning rates cannot be maintained for more than about 3 mo.
Dietary Threonine Requirement of Juvenile Red Drum Sciaenops ocellatus
Authors: Boren R. Scott , Gatlin Delbert M. 
Published: April 2007

AbstractThreonine is an indispensable amino acid required by all animals for normal growth and metabolic functions. An experiment was conducted in a brackish water (5 ± 1 ppt) recirculating system to quantify the minimum dietary threonine requirement of juvenile red drum Sciaenops ocellatus. The experimental diets contained 350/0 crude protein from red drum muscle and crystalline amino acids and 3.2 kcal available energy/g diet. Incremental levels of L‐threonine were added to the diets and fed to juvenile red drum initially averaging 2.8 g/fish for 8 wk. Weight gain and feed efficiency of fish fed the various diets were significantly (P < 0.05) affected and increased linearly as dietary threonine increased until plateauing around 0.8% of dry diet. Protein efficiency ratio and protein conversion efficiency values for fish fed the different diets also were significantly affected by threonine level and indicated requirement values of 0.8–0.9% of dry diet. Free threonine in plasma also significantly responded to increasing dietary threonine but indicated a slightly higher requirement value of approximately 1.0% of dry diet. Based on these data, the minimum threonine requirement of juvenile red drum was determined to be approximately 0.8% of dry diet (2.28% of dietary protein). This requirement level is similar to values reported for some other fish species. Based on this information diets may be formulated more precisely for aquacultural production of red drum.