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1.
Two 7 day feeding trials were conducted with channel catfish swim-up fry to evaluate growth, feed conversion ratio, and body composition of fish fed one of the following feeds: salmon starter, catfish starter, or trout starter. Fish fed the salmon or trout starter feeds gained 50–75% more weight, converted feed more efficiently, and had higher body fat stores than fish fed the catfish starter feed. This may be related to the higher protein and energy content of these two feeds. It may be advantageous to feed salmonid starter feeds to hatchery reared catfish fry; however, it is not known whether or not the improved performance observed in the hatchery continues once the fish are stocked into nursery and grow out ponds.  相似文献   

2.
Abstract.— Channel catfish Ictalurus punctatus fry are typically held under hatchery conditions for 7 to 14 d after hatching to allow feeding and growth before they are stocked into nursery ponds to produce fingerling catfish. In an attempt to reduce hatchery operating costs, several catfish fingerling producers in Louisiana presently stock fry within 2 d after hatching before yolk absorption is complete. Fry at this stage of development are commonly referred to as "sac-fry." Although research has shown that fry can be stocked at the onset of yolk absorption with no detrimental effects on subsequent fingerling production, stocking sac-fry has been reported to result in reduced fingerling survival. To further investigate this topic, production trials were conducted in experimental outdoor pools over the course of two growing seasons to evaluate the effect of stocking fry of three different ages (2-, 7-, and 14-d post-hatch, DPH) on survival, growth (weight and length), condition factor (K), yield, feed consumption, and feed conversion ratio (FCR) of fingerling catfish. Results from both trials indicated that the age at which fry were stocked had no effect on production characteristics with the exception of growth. Specifically, fingerlings reared from fry stocked at 2 and 7 DPH were significantly larger than fingerlings reared from fry stocked at an age of 14 DPH. These findings suggest that the practice of stocking sac-fry may be a suitable alternative to the traditional procedure of holding and feeding fry under hatchery conditions prior to stocking. However, in order to fully evaluate the effects of early-age stocking of catfish fry on fingerling production, additional studies must be conducted under pond conditions. Furthermore, these studies must be coupled with a rigorous economic analysis before the practice of stocking sac-fry can be recommended to the catfish industry.  相似文献   

3.
Fifty‐six days feeding trial was conducted to evaluate the effect of Cirina butyrospermi caterpillar meal (CBM) as protein source in replacement of fish meal (FM) for Clarias gariepinus fingerlings. Six hundred African catfish (initial mean weight = 2.42 ± 0.01 g) were fed with four approximate isonitrogenous (48.97% crude protein), isolipidic (15.85% crude lipid) and isocaloric (21.10 kJg?1) formulated diets, in which CBM progressively replaced FM at 0 (D1), 50 (D2), 75 (D3), 100% (D4) levels. At the end of the trial period, the best growth performance and nutritional utilization were observed in the group of fish fed with D2 and was not significantly different from those fed with D1 (the control diet). The survival rates, which ranged from 85.33% to 90.33%, were not significantly different among fish from the four diet treatments. The proximate whole‐body composition of C. gariepinus fingerlings fed the different diets showed similar moisture and protein contents. However, in contrary to ash which decreased, whole‐body lipid increased significantly when fish fed with diet containing CBM inclusion superior or equal to 75% (D3 and D4). The higher gross profit was obtained with D2 (16.73$), while the lowest was observed with D4 (10.16$). This study demonstrates that 50% of fish meal can successfully be replaced with CBM in C. gariepinus fingerlings diet without a negative impact on growth or feed utilization. This will yield a cheaper feeding for profitable production of African catfish fingerlings.  相似文献   

4.
The effect of scheduled use of high‐protein and low‐protein diets on body weight and fry production of Nile tilapia, Oreochromis niloticus (L.), was determined. A preliminary feeding trial was first conducted on fingerlings. These were fed a high‐protein diet (H, 25% protein) or a low‐protein diet (L, 18% protein) daily, or diet H for 1–3 days followed by diet L for 1–4 days. Final body weight was significantly higher (P < 0.05) in fish fed diet H daily and in fish fed diet H for 2–3 days followed by diet L for 1 day (2H?1L and 3H?1L). Fingerlings on 1H?1L and 3H?2L had slightly lower growth. Based on the response of the fingerlings, five feeding schedules were tested with the broodstock. A high‐protein diet (HP, 40%) and a low‐protein diet (LP, 25%; same as H for fingerlings) were used. Feeding schedules significantly influenced body weight of female but not the male fish. Fry production was not significantly affected by the feeding schedule for broodstock. When growth, fry production and saving in feed cost were all considered, the broodstock on 1HP?1LP and 3HP?2LP feeding schedules both gave the highest overall performance. These findings give fish farmers an option in the management of feeding of tilapia broodstock.  相似文献   

5.
Intensive tank rearing of channel catfish (Ictalurus punctatus Rafinesque) fry can be successfully accomplished with commonly available ‘salmonid’ starter diets. Ingredient substitution in starter diets is less important from the cost perspective but growth, survival and health of fish are major concerns. Several combinations of fish meals and animal protein substitutes were evaluated in diet formulations for hatchery rearing of catfish fry. Sub‐optimal thermal conditions were used which are characteristic for the north‐central USA where catfish culture is important for stocking purposes and live‐fish markets. A diet formulated on the basis of menhaden fish meal (29.1%), herring fish meal (25.1%) and animal by‐product mixture (16.38%) gave numerically the highest growth rate after 13 weeks of feeding, although growth reductions in fish fed diets exclusively with mehaden meal (77.6%) as protein or substituted with 50% animal by‐product protein were not significant. Instantaneous mortality rates were the highest between weeks 2 and 4 of rearing and increased almost proportionally with the increased fish meal protein substitution. A diet based on menhaden fish meal had the highest concentration of phosphorus and several other essential minerals, but these were not reflected in the mineral composition of the fish body at the termination of feeding. Among activities of digestive enzymes, trypsin was depressed in fish offered diets with 75–100% fish meal protein replacement. A diet superior in terms of fish performance was defined in the present study and it was concluded that the initial feeding can greatly affect physiological status of juvenile channel catfish.  相似文献   

6.
A 6-week feeding trial with four dietary protein levels (22%, 32%, 42% and 52%) and two dietary lipid levels (10% and 19%) was conducted to investigate the optimum dietary protein and lipid level for the growth of bagrid catfish fingerlings (0.92±0.01 g initial weight). Survival of fish was not affected by either dietary protein or dietary lipid level. Specific growth rate of fish fed the diets containing 10% lipid increased with increasing protein level and that of fish fed the diets containing 19% lipid increased with increasing protein level up to 42%. Feed efficiency of fish fed the 42% protein diet with 19% lipid and 52% protein diet with 10–19% lipid was higher than that of other groups. Daily feed intake of fish decreased with increasing dietary protein level at both lipid levels and showed a tendency toward higher values at 10% lipid diets than at 19% lipid diets. Protein efficiency ratio and protein retention of fish decreased with increasing dietary protein level, and those of fish fed the 19% lipid diet were higher than those of fish fed the 10% diet at 42% protein diet. Moisture content of fish fed 10% lipid diets was higher than that of fish fed 19% lipid diets, at each protein level. Crude lipid content of fish fed 19% lipid diets was higher than that of fish fed 10% lipid diets at each protein level. The results of this study indicate that an increase of dietary lipid level can improve growth and protein utilization, and the diet containing 42% protein with 19% lipid would be suitable for optimum growth and effective protein utilization of bagrid catfish fingerlings.  相似文献   

7.
A 30‐day feeding trial was conducted to evaluate dried fish and chicken viscera, and a combination of oil cakes as complete substitutes for fish meal in the diet of catfsh Clarias batrachus (Linn.) fingerlings. Triplicate groups of fingerlings with a mean initial body weight of 2.0 g were each fed four isonitrogenous diets at 4% of wet body weight. Performance of the diets was judged on the basis of feed acceptability, body weight gain, feed conversion ratio and protein efficiency ratio. A significant increase (P < 0.05) in body weight gain, protein efficiency ratio and a decreased feed conversion ratio (P < 0.05) was observed in fish fed on fish meal, followed by fish viscera, chicken viscera and only plant protein incorporated diets. Although inferior to fish meal and dried fish viscera, growth and feed utilization responses of fingerlings fed on dried chicken viscera and plant protein diets were similar. The fish accumulated a significantly greater (P < 0.05) amount of fat (18.3%) in the body carcass when fish viscera was incorporated in the diet. The study revealed that satisfactory growth and feed utilization responses could be achieved through replacement of fish meal by dried fish and chicken viscera in the diet of catfish fingerlings.  相似文献   

8.
Aflatoxins are a group of mycotoxins produced by the mold organisms Aspergillus flavus and A. parasiticus on feed grains and oil seeds such as corn, peanuts, and cottonseed. Research conducted in aquaria, about 15 yr ago, demonstrated that channel catfish Ictalurus punctatus are very tolerant to dietary aflatoxin B1 (AFB1) from a purified source. To evaluate the effect of feeding diets containing aflatoxin from a natural source, moldy corn (MC) naturally contaminated with a high concentration (550 pg/kg) of total aflatoxins was incorporated into practical diets. The diets were fed to Juvenile catfish in two experiments. Experiment 1 consisted of feeding catfish (mean body weight 7.1 g/fish) four diets containing 20% or 40% of two lots of corn; one with no apparent mold contamination, which was designated as clean corn (CC), or the previously described MC. Each diet was fed twice daily to five 100-L aquaria of 20 fish each for 12 wk. Experiment 2 consisted of three diets containing either 50% CC or MC, or a combination of 25% CC and 25% MC prepared by the cooker-extrusion method. Each diet was fed once daily for 130 d to five replicate 0.04-ha ponds of catfish fingerlings. Results of these experiments indicate that feeding diets containing aflatoxin from moldy corn does not affect channel catfish weight gain, feed consumption, feed efficiency, survival, hematocrit, or hepatosomatic ratio. No liver abnormalities were observed upon gross examination. Levels of aflatoxin were reduced approximately 63% in the diets used in experiment 2 after exposure to the high temperature (ca. 120 C) of the cooker-extrusion process used to manufacture commercial catfish diets.  相似文献   

9.
A study was conducted to evaluate low‐protein traditional or alternative diets for pond‐raised hybrid catfish, Ictalurus punctatus × Ictalurus furcatus. Three 24% protein diets containing decreasing levels of soybean meal (30, 20, and 15%) and increasing levels of cottonseed meal and corn germ meal were compared with a 28% protein control diet. Hybrid catfish fingerlings (mean initial weight = 71 g/fish) were stocked into 20 earthen ponds (0.04 ha) at a density of 14,826 fish/ha with five ponds per dietary treatment. Fish were fed once daily to apparent satiation for a 191‐d growing season. There were no significant differences in total diet fed, net yield, weight gain, feed conversion ratio (FCR), survival, or fillet proximate nutrient composition among dietary treatments (P ≥ 0.10). However, regression analysis showed for fish fed 24% protein diets there was a linear increase in FCR as soybean meal levels decreased (P = 0.06). Compared with fish fed the 28% protein control diet, fish fed 24% protein diets had lower carcass and fillet yield. Results demonstrate a 24% protein alternative diet containing 20% soybean meal may be substituted for 28% protein diets for hybrid catfish during food fish production.  相似文献   

10.
The present study was performed to evaluate the effect of using Artemia biomass, by‐product from Artemia cyst production on growth and feed utilization of goby Pseudapocryptes elongatus fingerlings. A control diet containing fishmeal as main protein source was compared with four experimental diets in which fishmeal protein was replaced by increasing dietary levels of Artemia protein, namely 25%, 50%, 75% and 100%. The five test diets were compared with a commercial diet and dried Artemia. All diets were formulated to be equivalent in crude protein (360–370 g kg?1) and lipid (58–65 g kg?1). The experiment was conducted in 80 L plastic tanks filled with water at a salinity of 15 g L?1. Goby fingerlings with 0.21 g initial weight were fed the test diets for 30 days. The results showed that weight gain and specific growth rate of goby were positively correlated with total feed intake. Moreover, growth performances and feed utilization in the fry receiving the commercial feed and fishmeal control diet were similar, both were inferior to the groups fed dried Artemia and the based formulated diets. These results illustrate that both dried Artemia and Artemia‐based feeds can be used for feeding goby fingerlings, indicating the high potential of using locally produced Artemia biomass, which could contribute to reduce the reliance on fishmeal and improve profits for Artemia producers.  相似文献   

11.
Abstract

This study evaluated the effects of dietary protein concentration (26, 28, and 32%) and an all-plant protein diet (28% protein) on growth, feed efficiency, processing yield, and body composition of channel catfish, Ictalurus punctatus raised from advanced fingerlings to large marketable size (about 800 to 900 g/fish) for two growing seasons. Fingerling channel catfish (average weight = 56 g/fish) were stocked into twenty 0.04-ha ponds at a density of 18,525 fish/ha. Fish were fed once daily to satiation during the two growing seasons and fed according to recommended winter feeding schedules during the winter. There were no differences in diet consumption, weight gain, feed conversion ratio, survival, processing yields (carcass, shank fillet, and nugget), or fillet composition (moisture, protein, fat, and ash) among fish fed the various diets. These results indicate that a 26% protein diet containing plant and animal proteins or a 28% all-plant protein diet is adequate for channel catfish raised in ponds from advanced fingerlings to large marketable size without adversely affecting weight gain, feed efficiency, processing yield, or body composition. Large marketable-size channel catfish appear to use diets less efficiently but give higher processing yields compared to small marketable-size fish.  相似文献   

12.
Experiment was conducted to ascertain the effect of l ‐carnitine on growth and body composition of Cirrhinus mrigala fry (0.342 ± 0.03 g) using five different concentrations (0.25, 0.50, 0.75, 1, and 0%) of l ‐carnitine‐incorporated diets for 120 d. At the end of trial, weight gain, feed conversion efficiency, and protein efficiency of fishes fed with 0.25% l ‐carnitine diet were observed to be significantly higher. Poor growth was recorded in the fry fed diet with no carnitine, while intermediate growth was observed when fed with 0.50, 0.75, and 1% l ‐carnitine‐incorporated diets. The analysis of body composition of C. mrigala fry indicated that there is no significant difference (P > 0.05) in moisture, protein, and ash contents, but significant difference (P < 0.05) was found in body lipid content of fry, fed with different concentrations of l ‐carnitine. Decrease in viscerosomatic and hepatosomatic indices were observed in fishes fed with l ‐carnitine‐incorporated diets. Results of this study indicated that diet containing 0.25% l ‐carnitine can promote higher growth in C. mrigala fry.  相似文献   

13.
Abstract

The performance of poultry layer waste (PLW) meal as a dietry protein inclusion for hybrid clariid catfish (Clarias gariepinus♂ ×Heterobranchus bidorsalis♀) fingerlings (hetero-clarias), cultivated in glass tanks, was evaluated. Four isonitrogenous diets (35% crude protein) were fed to unsexed hetero-clarias fingerlings for 90 days. The inclusion levels of the PLW meal were at 0%, 10%, 20% and 30%. Growth performance and nutrient utilization of the fish were based on percentage daily weight gains, specific growth rate, feed conversion ratio and protein efficiency ratio. There were no significant differences (P> 0.05) in growth performance and nutrient utilization of the fishes fed on diets containing up to 30% PLW inclusion. All fish fed diets containing PLW did better (P> 0.05) than those fed the control diet. The most cost-effective diet in terms of cost-weight gain was diet containing 10% PLW. These results indicate that up to 30% of PLW meal could be included in the diet of hybrid diet catfish.  相似文献   

14.
The 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.  相似文献   

15.
Nitrogenous waste control in aquaculture systems is necessary to maintain healthy animals and to meet effluent standards. Decreased ammonia production has been attained in traditional livestock production systems by adding extracts of Yucca shidigera to the feed or storage lagoon system. An extract of Yucca shidigera was fed to post yolk-sac and juvenile channel catfish Ictalurus punctatus and hybrid tilapia Oreochrornis mossambicus × O. niloticus to determine the effects on growth, nitrogen retention, ammonia excretion, and toxicity. Post yolk-sac channel catfish fry fed the 1.0-g yucca extract/kg as an agar coating were the only group of experimental organisms that had significantly greater weight gains compared to the control and 0.5-g yucca extract/kg diet groups after 12 wk. Significantly lower fecal nitrogen concentrations were obtained from catfish fed diets containing yucca extract compared to the control groups, although no differences between fecal nitrogen concentrations for catfish fed diets with either 0.5-g or 1.0-g yucca extract/kg diet occurred. Ammonia excretion rates were significantly lower for catfish fed diets containing yucca extract compared to the control group. Accordingly, fish fed diets containing the yucca extract had significantly greater whole-body protein composition, while lipid levels were significantly lower. No significant differences in proximate composition occurred for fish fed any of the diets containing yucca extract, though growth rates were significantly higher than the controls. This study demonstrated that a yucca extract can be used in the diet of channel catfish, and increased growth and decreased ammonia concentrations can be obtained in rearing systems.  相似文献   

16.
This study examined four experimental diets with different protein concentrations and sources for pond‐raised fingerling hybrid catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus. A 35% protein diet with fishmeal was used as the control diet. Test diets were 32 and 28% all‐plant‐protein diets and a 28% protein diet with porcine meat, bone, and blood meal. Small fingerlings with a mean initial weight of 2.9 g/fish were stocked into 20 earthen ponds (0.04 ha) at a density of 172,970 fish/ha. They were fed once daily to apparent satiation for 107 d. No significant differences were observed for total diet fed, gross yield, final weight, survival, or condition factor among dietary treatments. However, fish fed the 28 and 32% all‐plant‐protein diets had a significantly higher feed conversion ratio than fish fed the 35% protein diet with fishmeal. There were no significant differences in chlorophyll a and nitrite concentrations in the pond water, but ponds receiving the 35% protein diet had significantly higher ammonia than those receiving 28% protein diets. Economic analysis suggested potential cost savings by using low‐protein and all‐plant‐protein diets for hybrid catfish fingerling production.  相似文献   

17.
Two experiments were conducted to evaluate various ingredient combinations in a 28% or 32% protein diet for optimum performance of channel catfish Ictalurus punctatus. All diets contained soybean meal and corn, but with or without cottonseed meal, wheat middlings or fish meal (FM). Channel catfish fingerlings were stocked into 0.04 ha earthen ponds at 18 530 fish ha?1. Fish were fed one of eight diets once daily to apparent satiation for two growing seasons. Results demonstrated that the dietary ingredient composition used had significant effects on fish performance, but magnitude of differences was relatively small. Overall, diets containing FM resulted in greater weight gain (Experiments 1 and 2) and lower feed conversion ratio (Experiment 1) than fish fed all‐plant diets. However, certain combinations of plant ingredients provided the similar fish growth as some diets containing FM. There were no significant differences in weight gain between fish fed soybean meal–corn or soybean meal–corn–wheat middlings‐based diets with cottonseed meal or FM. The use of wheat middlings in the diet had no significant effects on fish production characteristics.  相似文献   

18.
The 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.  相似文献   

19.
20.
Three levels of dietary protein (26, 28, or 32%) and four levels of animal protein (0, 2, 4, or 6%) were evaluated in a factorial experiment for pond-raised channel caffish using practical-type extruded feeds. Meat, bone, and blood meal (65% protein) was used as the animal protein source. Channel catfish fingerlings (average weight: 69 glfish) were stocked into 48 0.04-ha ponds at a rate of 24,700 fishha. Four ponds were used for each dietary treatment. Fish were fed once daily to apparent satiation for 158 d. No differences were observed in weight gain, feed consumption, feed conversion ratio, survival, and hematocrits of channel catfish fed diets containing various levels of dietary protein and animal protein. Inclusion of animal protein in the diet did not affect fish dressout, percentage visceral fat, or fillet composition. Comparison of means pooled by dietary protein without regard to animal protein showed that fish fed diets containing 26% protein had a lower percentage dressout than fish fed higher protein diets (55.4% vs. 56.3%). Fish fed the 32% protein diet had lower visceral fat than those fed the 26% or 28% protein diet (2.9% vs. 3.6% or 3.4%). Fillet fat was lower for fish fed the 32% protein diet than for fish fed the 26% protein diet (5.8% vs. 7.1%). Fillet fat in fish fed the 28% protein diet (6.5%) was not different from fish fed either 26% or 32% dietary protein. No differences were detected in fillet protein, moisture, and ash concentrations among fish fed diets containing various concentrations of protein. There were no interactions between dietary protein and animal protein for any variables. Results from the present study indicate that animal protein can be eliminated from diets for grow out of channel catfish fed to apparent satiation using diets containing 26% to 32% crude protein.  相似文献   

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