Growth Rate Of Fry Research Articles

Growth and survival of Clarias catfish (Clarias gariepnus B., 1822) at different stages of cultivation with the addition to the fodder of “Chiktonik”

Stressful situations decrease the growth rate and survival rate of fish, thus, the search for ways to reduce their adverse impact is relevant. The purpose of the research – to evaluate in aquaculture conditions the effect of different concentrations of vitamin-amino acid complex “Chiktonik” on the growth and survival of larvae and fry of African clarius catfish (Clarias gariepinus B., 1822) after stressful situations. The stressful situation for the fish arose from significant fluctuations in the content of ammonia, nitrites and nitrates in the water environment of the closed recirculation aqua system during the period of start-up of the biological filter, until the equilibrium was established. A series of experiments were performed, during which it was established that the addition of the drug at the rate of 1 ml per 1 kg of feed accelerates the growth of fish in experimental variants compared to the control. Experimental use of high doses of the drug (5, 15, 30 and 45 ml/kg of fodder) initially inhibited the growth of fish body weight, but 10-30 days after the experiment, the growth rate of the experimental material was equal to that of the control group of fish and even exceeded the control values in the future. The positive effect of the vitamin-amino acid complex “Chiktonik” on the survival of young clarius catfish at the stage of completion of the larval period of life and in the early stages of the fry period was established. In the experiment with older fish, which were fully developed fry, such an effect of the drug was not observed: the survival rate of fish was at the same level both in the experiment and in the control. Therewith, it was established that the fry reacted worse to higher doses of the drug compared to the grown larvae. The growth rate of fry after using high doses of the drug did not equal that of fish from the control group within a month after the experiment, unlike younger fish. In general, the expediency and safety of the practical use of the drug “Chiktonik” for young clarius catfish as a fodder additive at a dose of 1 ml/kg of fish fodder have been proved

Effects of Light Intensity and Photoperiod on the Growth Performance of Largemouth Bass (Micropterus salmoides) in Recirculating Aquaculture Systems

HighlightsLight design is needed in recirculating aquaculture systems.A long photoperiod is beneficial to largemouth bass growth.Low light intensity is beneficial to largemouth bass growth.Abstract. In this study, recirculating aquaculture systems (RAS) were used to culture juvenile largemouth bass, and the effects of LED light intensity and photoperiod on the survival and growth performance of juvenile largemouth bass were studied. In the light intensity experiment, largemouth bass juveniles with an initial weight of 0.53 ±0.02 g were subjected to a two-month feeding experiment under two different light intensities: group A, at 0.5 W m-2 in the first month and 5 W m-2 in the second month; and group B, at 5 W m-2 in the first month and 0.5 W m-2 in the second month. The results showed that in the first month of the experiment, the growth rate of fry was faster in group A than in group B. After changing the light intensity, the weight of the fry in group B after one month of growth had exceeded and was significantly higher than that in group A. Based on the above experimental results, we conducted a photoperiod experiment. Largemouth bass juveniles with an initial weight of 0.56 ±0.02 g were cultured for two months under four different photoperiods (24L:0D, 16L:8D, 8L:16D, and 0L:24D). The light intensity of the four groups was 0.5 W m-2. The fry growth rate was fastest in the 24L:0D photoperiod group and slowest in the 0L:24D photoperiod group. The growth rate of the 24L:0D photoperiod group was significantly higher than that of the 0L:24D photoperiod group (p < 0.05). The final fry weight was highest in the 24L:0D group, followed by that in the 16L:8D group and 8L:16D group, with the lowest weight observed in the 0L:24D group (p < 0.05). Although the different light conditions in the two experiments had no significant effect on the survival rate of juvenile largemouth bass (p > 0.05), a low-intensity light environment with a continuous photoperiod during the juvenile largemouth bass culture process promoted growth and development. Keywords: Growth, Largemouth bass, Light intensity, Photoperiod, RAS.

Dietary supplementation of L-tryptophan: Effect on growth and survival of Pabda, Ompok bimaculatus (Bloch) fry

ABSTRACT A 30-day experiment was conducted to assess the effect of tryptophan-supplemented diets on growth and survival of Pabda, Ompok bimaculatus fry. Fifty pabda fry (0.114 ± 0.02 g; 2.45 ± 0.13 cm) were stocked into each aerated aquarium following a completely randomized design consisting of four treatments with triplicate each. Four iso-proteinious purified diets were prepared with different levels of tryptophan—0%, 1%, 2%, and 3%—of the dry diet and were designated as Control, TRP1, TRP2, and TRP3 respectively. Fishes were fed with the experimental diet ad libitum four times a day. The results showed that fish fed with tryptophan-supplemented diets exhibited significantly (P < 0.05) lower cannibalism and higher survival than the control diet. Further, the tryptophan-supplemented groups showed a significantly lower coefficient of variation (%) and size heterogeneity (P < 0.05). However, the growth as measured by body weight gain, length increment, and specific growth rate of fry in tryptophan-supplemented groups was significantly lower than the control group (P < 0.05). Moreover, maximum survival (52.67 ± 1.76%) and minimum cannibalism (21.33 ± 5.70%) coupled with higher growth and performance index (0.38 ± 0.01) were recorded in the 2% tryptophan-supplemented group compared to other tryptophan-fed groups. Overall interpretation from the present study concludes that the dietary supplementation of 2% tryptophan is recommended for better survival of pabda fish, although growth was compromised.

Costs and benefits of biparental mucus provisioning in discus fish (Symphysodon aequifasciatus)

We tested the manner in which the number of fry influences the costs and benefits of mucus provisioning in discus fish (Symphysodon aequifasciatus) via two experiments. In experiment-1, we found that fry grew more rapidly when they were raised with parents than when raised without parents, suggesting that fry benefits from the mucus provisioning by parents. In experiment-2, a reduction in the body weight of parents correlated with brood size. The growth rate of fry did not linearly correlate with brood size. We discuss the functions, costs, and benefits of mucus provisioning in discus fish.

Community Based Milkfish Farming in Tanzania

In the 1990s experimental integrated mariculture of finfish, shellfish and seaweeds in a flow through system was developed to investigate bio-filtration in the ponds. The project supported mainly by WIOMSA culminated in a stakeholders’ workshop in 2004 translating the results of the experiment to community based projects. The finfish tested were milkfish ( Chanos chanos ), rabbit fish ( Siganus canaliculatus and S. sutor ), mullet ( Mugil cephalus ) and Zanzibar tilapia ( Oreochromis urolepis hornorum ). Before the workshop there were 3 milkfish mariculture ponds in Tanzania one of which was established by IMS. Following the workshop, pond finfish mariculture took off in the coastal Tanzania. In 2006, the first commercial type farm at Bagamoyo produced 1 MT/ha/yr, earning the group 2000 USD. Ever since, finfish farming has spread to all coastal districts with the highest production of 7.5 MT/ha/yr at Ndumbwe Mtwara in 2011. In 2011, trials of tilapia acclimatization and farming in estuarine and full strength sea water were started where survival and growth rates of fry and fingerlings of 4 species of tilapia were tested.

Performance of Different Dietary Lipids on Growth Indices and Survival of Striped Gourami, Colisa Fasciatus (Perciformes: Osphronemidae) Fry

Effects of different types of lipids enriched supplemental diets containing 1% docosahexaenoic acid (DHA), 1% Phospholipids, 5% Cod liver oil and 1% Cod liver oil and live feed (Tubificid worms) on growth indices and survival of Colisa fasciatus fry were observed. The experiment was conducted in triplicates with a control for 50 days following randomized complete block design (RCBD). The water quality parameters were monitored and found to be within suitable range for freshwater aquaculture. After ending the trial period, significant variations (P<0.05) were observed on the survival and specific growth rate of fry among all the treatments. These results indicate that there are significant variations among different lipids on performance of fry and DHA showed the highest performance regarding growth indices and survival (in close proximity to live feed) among all the biofunctional lipids as an ingredient of supplemental diet.

Effect of dietary phospholipid sources and levels on growth performance, enzymes activity, cholecystokinin and lipoprotein fractions of rainbow trout (Oncorhynchus mykiss) fry

This study was conducted to evaluate the effect of soybean lecithin (SBL) and chicken egg lecithin (EGL) on growth performance; pancreatic and intestine enzymes, cholecystokinin (CCK) and lipoprotein fractions of rainbow trout, Oncorhynchus mykiss (Walbaum) fry. Seven isonitrogenic and isolipidic diets were prepared by replacing 0 (as a control), 2%, 4% and 6% soybean and chicken egg lecithin instead of soybean oil in diets. Trout fry with initial average weight of 120 ± 4.08 mg, were randomly distributed in 21 90 L tanks. Triplicate groups (165 fish for each tank) of fry were fed each diet to visual satiation at six meals per day for 40 days. Dietary supplements of 2% and 4% chicken egg lecithin led to increase in fry final weight, weight gain and specific growth rate suggesting that moderate PL levels are needed during this stage of rainbow trout. Also 2% chicken egg lecithin caused significantly higher activity of amylase, lipase, phospholipase A2, alkaline phosphatase (AP), aminopeptidase-N (AN) and lower activity of leucine alanine peptidase (leu-ala) in the digestive tract of fry than those in control group. Furthermore, fry fed 2% chicken egg lecithin had a higher ratio of AN/leu-ala and AP/leu-ala than that in the control group. Chicken egg lecithin increased significantly cholecystokinin (CCK) and chylomicron fractions of fry compared to control group. It is noteworthy that soybean lecithin had moderate effect on final growth, weight gain and specific growth rate of fry and induced significantly higher activity of amylase, lipase, phospholipase A2 and secretion of CCK compared to control group. The results of this study indicate that dietary supplementation 2% chicken egg lecithin indirectly through some biochemical parameters improves growth performance of rainbow trout fry.

Substitution of fish meal by sesame oil cake (Sesamum indicum L.) in the diet of rainbow trout (Oncorhynchus mykiss W.)

The present study evaluated the nutritional value of sesame oil cake (SOC) in rainbow trout fry (initial body weight of 1.42 g) in a growth trial performed for 45 feeding days at 15 ± 1 °C. A series of five isonitrogenous (380 g digestible protein kg−1 dry matter (DM)) and isoenergetic (18.1 MJ digestible energy kg−1 DM) diets were formulated in which the digestible SOC protein progressively replaced 0%, 13%, 26%, 39% and 52% of the digestible protein of a high quality fish meal (D0-D52). Growth rate of fry significantly improved in fish fed SOC diets compared to the fishmeal control diet (D0) whatever the SOC inclusion level. This positive effect on growth was mainly related to a marked improvement of voluntary feed intake. The decrease of feed efficiency observed with increasing SOC was entirely explained by the reduction of DM and energy digestibilities with SOC incorporation. Nitrogen retention efficiency (nitrogen gain/nitrogen intake) was high (40–41%) and significantly reduced only in fish fed D52 (37%). Our results suggest that SOC can be a suitable protein source for a carnivorous fish and replace at least half of the fishmeal protein (without amino acid supplementation) without growth reduction in rainbow trout fry.

Increased performance of offspring sired by parasitic males in bluegill sunfish

Males of many species are characterized by alternative mating tactics. In bluegill sunfish (Lepomis macrochirus), some males delay maturation and become ‘‘parentals’’ while other males mature precociously and become ‘‘cuckolders.’’ Parentals use an overt, territorial mating tactic, defending a nest and courting females. Cuckolders instead use a sneaking tactic to parasitize parentals. It has previously been shown that parentals that are heavily cuckolded provide less care to their young, yet females do not appear to discriminate against cuckolders, and they may actually release more eggs when a cuckolder is present than when spawning only with a parental. Here I examined growth rate of fry of known paternity through the yolk-sac stage of development using complementary laboratory and field studies to assess a potential indirect benefit for females that mate with cuckolders. Comparison of maternal half-siblings sired in vitro shows that cuckolder offspring grow faster and to a larger size than parental offspring while feeding endogenously on their yolk sac. Because both food resource and maternal genes are equivalent across treatments, these data indicate a genetic difference in growth between the two male life histories. In the field, fry from nests that have proportionately more cuckolder offspring are larger when they emerge from the nest. This increased size can lead to threefold higher survivorship for cuckolder offspring than parental offspring from Hydra canadensis predation, a major predator of bluegill fry. These results are discussed in the context of mate choice for direct and indirect benefits and in the context of the evolution of alternative mating tactics. Key words: bluegill sunfish, good genes, growth rate, indirect benefits, Lepomis macrochirus, mate choice, mating systems. [Behav Ecol 15:327–331 (2004)]

Production of Exotic &lt;I&gt;Clarias gariepinus&lt;/i&gt; Fingerlings at Varying Stocking Densities in Outdoor Concrete Ponds

The effect of stocking density on the production of exotic Clarias gariepinus fry to fingerling stage was examined during the nursery phase in outdoor concrete tanks. The fry were held at five stocking densities of 250, 500f, 750,1000 and 1250 fry/m3. There was significant difference (P < 0.05) in the mean weight gain per day and specific growth rate of fry held at the different stocking densities. The mean weight gain and specific growth rate decreased as stocking density increased. The development of “jumpers” increased as the stocking density increased. Higher stocking density gave rise to bigger “jumpers”. There was significant difference (P > 0.05) in the survival of the fry held at the different stocking densities. Highest survival was obtained at stocking density of 250 fry/m3 while stocking density of 1250 fry/m3 gave the lowest survival. Fry held at 250 fry per cubic metre gave the optimum stocking density. Key words: Exotic Clarias gariepinus, stocking density, fry, fingerling, jumper. Journal of Aquatic Sciences Vol.18(1) 2003: 21-24

Young of the Midas cichlid get biologically active nonnutrients by eating mucus from the surface of their parents

Fry (first mobile offspring) of the Midas cichlid,Cichlasoma citrinellum, feed on the epidermal mucus of their parents. Ingesting mucus increased at first then fluctuated during the four-week period of parental care of swimming young (fry). Total protein in the mucus was assessed using Bio-Rad-Protein-assays. Western blots revealed prolactin (tiPRL 177 and traces of tiPRL 188) and growth hormone (tiGH). Thyroxine (T4) was also detected quantitatively by RIA. Fry with parents grew faster initially than those raised without. The growth rate of fry isolated from parents increased, however, when fed daily about 0.01 mg ovine PRL or ovine GH.

Techniques for Rearing Margined Madtom Fry

Abstract The margined madtom Noturus insignis was used as a model species to develop methods for rearing madtoms in the laboratory. Commercial flake food, salmon starter, Larval AP 100, Kyowa Fry Feed, and brine shrimp Artemia sp. were tested as diets. In rearing trials, mean growth rates of fry ranged from 0.17 to 0.58 mm/d, and the fastest growth rates were obtained with brine shrimp as part or all of the diet; however, the highest survival was obtained with a diet of salmon starter. Approximately half of the total fry mortality occurred within the first 2 d in feeding trials, and mortality after 5 d was low. Tanks apparently need to be thoroughly cleaned twice daily to ensure good survival of larvae and fry. The rearing system used in this study and a stocking density of only one fish per 2 L of water precluded large die-offs, even when parts of the system failed. Twice-daily feedings of 300–400 mg of salmon starter per 38-L tank, supplemented with about five brine shrimp nauplii per milliliter, are recommended for rearing madtom larvae to 2–3 weeks of age. After that time, a diet of salmon starter is suitable for rearing larvae to the juvenile stage.

PEMBENIHAN NILA MERAH (Oreochromis sp.) MENGGUNAKAN JARING APUNG DI WADUK KEDUNGOMBO

The objectives of the research were to know the production of hatchery, survival rate and growth rate of fry. Floating nets were made for plastics hapa (2 mm mesh size) with 3 different size (5 m2, 10 m2, and 15 m2). The larvae were stocked in different hapa nursery size ( 1 m3, 2 m3, 3 m3) at the rate of 1000 larvae/m3 of water. The fry produced from the first nursery were subsequently reared in waring (mesh size 0,04 cm) at density of 600 fry/m3 of water. The spawning were conducted for 6 months, while larvae rearing were 2 months for each period respectively. The result showed that the hatchery of 15 m2 scale were technically and biologically feasible. During 6 months period it produced 11,870 fingerling of 40 gram, 3,028 fry of 4 gram and 4,290 of larvae. The survival rate and growth rate of fry water not significantly affected by different hapa size either in the first and second nursery. The survival rate of the first nursery was 64.70-72.63% of 5.0-6.8 cm fry, while the second nursery was 97.29-98.30% of 11.5-12.4 cm fry.

Larval rearing of an African catfishHeterobranchus longifilis(Teleostei, Clariidae): effect of dietary lipids on growth, survival and fatty acid composition of fry

Legendre M., N. Kerdchuen, Ci. Corraze, P. Bergot. Aquat. Living Resour., 1995, 8, 355-363. With the aim of improving dry diets for first feeding of Heterobranchus long$lis larvae, the effect of dietary lipid sources on growth rate, survival rate and fatty acid composition of fry from 2 days up to 17 days of age was evaluated. Six feeding regimes were tested: Artemia nauplii which served as a reference, and 5 experimental dry diets diffenng only by the lipid source. The different oils used for the different expenmental diets were the following: cod liver oil, palm oil, copra oil, peanut oil and cotton seed oil. Each diet was tested on duplicate groups of 400 larvae placed in the 40 1 tanks of a recirculating system (27-29°C) and fed to excess six times per day every 4 hours. Separation and identification of the fatty acids of diets, eggs and fry were carried out by gas-liquid chromatography. After 15 days of feeding, survival rates were high for al1 treatments (71-87%) and did not differ significantly. By contrast, growth rates were largely influenced by the feeding regime. Fry fed with Artemia were significantly bigger (289 mg) than those fed artificial dry diets (79-1 15 mg). However, it was found that the specific growth rate of fry fed Artemia was supenor to that of fry receiving dry diets only for fish of less than 50 mg body weight, indicating that Artemia presents a nutritional advantage only for fry at their youngest stages of development (first 6 days of feeding). Among the artificial dry diets, the best results were obtained with diets containing palm or copra oil, the lowest growth rate being observed with the cod liver oil diet. Peanut and cotton seed oil diets led to intermediate results. The fatty acid composition of the whole fry reflected that of the experimental diets. Al1 together, the results indicated the existence of an optimal ratio between n-3 and n-6 fatty acids for covenng essential fatty acids requirement of the fry. Growth rates tended to be reduced by an excess of n-3 fatty acids (cod liver oil) or by an excess in n-6 fatty acids (cotton seed oil) as well. Evidence of the occurrence of HUFA (20:4n-6 and 22:6n-3) biosynthesis are given.

X-Ray-Induced Changes in Growth of Mozambique Tilapia

Abstract Early fry (30 d postfertilization) and 7–8-week-old Mozambique tilapias (Tilapia mossambica) were exposed to X rays in dosages of 50, 100, 200, 300, 400, or 500 roentgens and reared in outdoor culture tanks between May 1981 and October 1988. Fish of either sex that were irradiated as fry grew faster than controls at all test X-ray doses. Among fish irradiated at age 7–8 weeks, males grew significantly faster, but females grew significantly slower, than controls at all test doses. X-ray-induced changes in growth were dose-dependent: growth rates of fry (both sexes) and of juvenile males rose relative to those of controls with increased radiation dose. The growth increase per unit of radiation dose was higher for fry than for older juveniles. The length–weight regression was steeper for irradiated males than for controls. The average weights of F1 offspring of irradiated fish were greatly reduced as compared with controls, which suggests the transfer of the detrimental effects of X rays from irradiated parents to their offspring.

Effects of temperature on hatchability, development and growth of eggs and yolksac fry of Oreochromis mossambicus (Peters) under artificial incubation

. The eggs and yolk sac fry of the mouth brooding tilapia. Oreochromis mossambicus (Peters), were artificially reared in an experimental hatchery system at different temperatures. The hatchability, embryonic development of eggs and growth of yolk sac fry were studied under controlled conditions. It was shown that the upper lethal temperature for O. mossambicus eggs was above 40°C and the lower lethal temperature between 11°C and 17°C. For yolk sac fry these values lay between 34 and 40°C and 17 and 20°C respectively. Fry survival between 24·3 and 34·0°C was near to 100% while al 20°C it was less than 60%. The somatic growth rates of fry at temperature between 20 and 34·5°C up to 10 days post hatch are presented and were found to differ significantly. At 34·6°C a negative SGR was recorded during the period 6–9 days post hatching, but, during the first 6 days, the SGR at this temperature was more than four times higher than at 20°C. At the elevated temperatures, the utilization of yolk is faster and the loss of weight observed was due to starvation. This should be taken into account when incubating under artificial rearing condition so that initiation of exogenous feeding is timed most appropriately.

Choline Requirement of Swim-Up Rainbow Trout Fry

Abstract Triplicate 150-fish lots of first-feeding fry of rainbow trout (Oncorhynchus mykiss; initial mean weight, 0. 12 g) were fed casein–gelatin-based diets containing 0, 200, 400, 800, 1,000, 2,000, 4,000, or 8,000 mg choline/kg of feed for 12 weeks to determine their need for dietary choline. Although the growth rates of fry were suboptimal, results showed that fry needed no more than 4,000 mg choline/kg casein–gelatin diet for maximum growth and 2,000 mg/kg for maximum body fat and minimum protein. Survival was significantly lower for fish fed 800 mg choline/kg of diet than for those fed greater amounts of the nutrient. These results suggest that the dietary choline requirement of early feeding salmonids is greater than that previously reported for older salmonids. The amount of choline needed by fishes apparently decreases with age or size.

Genetic Differences in the Early Development and Growth of Sympatric Sockeye Salmon and Kokanee (Oncorhynchus nerka), and their Hybrids

Anadromous (sockeye salmon) and nonanadromous (kokanee) Oncorhynchus nerka spawn sympatrically yet appear genetically distinct in a number of rivers in British Columbia. To investigate whether genetic differences are maintained by selection against -hybrid" progeny, we raised pure and reciprocal crosses of Shuswap River sockeye and kokanee under controlled hatchery conditions. Sockeye eggs were larger and survived slightly better than kokanee eggs, regardless of male type, both to the eyed egg stage and as young fry. We observed no differences in survival among cross types during the remainder of the 460 d study. Rate of yolk absorption was similar in pure sockeye and pure kokanee alevins, but significantly faster in alevins sired by sockeye than those sired by kokanee. This indicates a male genetic effect which compensates for the difference in egg size. Hybrid alevins developed differently because egg size is mismatched with the male genotype. Growth rates of fry were significantly more variable within pure kokanee families than within pure sockeye families Hybrid crosses survived as well as pure crosses under the study conditions. However, any progeny resulting from hybrid crosses in nature may sustain higher mortality than those from pure crosses.

Summer Habitat Utilization and Ecology of Cutthroat Trout Fry (Salmo clarki) in Cascade Mountain Streams

Emergent cutthroat trout fry (Salmo clarki) were observed in the margins, backwaters, and side channels, collectively called "lateral habitats," of three study streams with different riparian vegetation. Most fry remained in these lateral habitats until the end of their first summer. The abundance of cutthroat fry was proportional to the area of lateral habitat in each of the study streams. Average size and growth rate of fry were related to the effect of site elevation on stream temperature and the influence of riparian vegetation on the availability of invertebrate food. Lateral habitats are characterized by slow, shallow-water, abundant detritus and benthic invertebrate assemblages of high density. Stream margins and backwaters provide gradients of depth and velocity, cover, and access to food that are appropriate to the habitat requirements of fry. Because fry populations are closely related to the abundance and quality of lateral habitats in small streams, these habitats should be included in the assessment of habitat requirements of cutthroat trout.

An experimental study on the culture of fry of Oreochromis mossambicus (Peters) in a peaty swamp in Sri Lanka using cowdung and poultry manure as fertilizer

Growth rates of fry of Oreochromis mossambicus were studied in a dug-out pond in Muthurajawela swamp, which had been fertilized with cowdung and poultry waste. This swamp is characterized by waters with very low pH, low dissolved oxygen and low values of primary productivity. The addition of fertilizer increased the gross primary production from 0.18 g C/m 2-day to 1.08 g C/m 2-day in about 40 days, with pH and dissolved oxygen values becoming favourable for growth of fry. The average growth rate of 0.04 g/day was comparable to the growth rates attained in favourable habitats in Sri Lanka.