Growth and energy budget of F-2 'all-fish' growth hormone gene transgenic common carp

The growth and energy budget for F-2 'all-fish' growth hormone gene transgenic common carp Cyprinus carpio of two body sizes were investigated at 29.2 degrees C for 21 days. Specific growth rate, feed intake, feed efficiency, digestibility coefficients of dry matter and protein, gross energy intake (I-E), and the proportion of I-E utilized for heat production (H-E) were significantly higher in the transgenics than in the controls. The proportion of I-E directed to waste products [faecal energy (F-E) and excretory energy loss (Z(E) + U-E) where Z(E) is through the gills and U-E through the kidney], and the proportion of metabolizable energy (M-E) for recovered energy (R-E) were significantly lower in the transgenics than in the controls. The average energy budget equation of transgenic fish was as follows: 100 I-E = 19.3 F-E + 6.0 (Z(E) + U-E) + 45.2 H-E + 29.5 R-E or 100 M-E = 60.5 H-E + 39.5 R-E. The average energy budget equation of the controls was: 100 I-E = 25.2 F-E + 7.4 (Z(E) + U-E) + 35.5 H-E + 31.9 R-E or 100 M-E = 52.7 H-E + 47.3 R-E. These findings indicate that the high growth rate of 'all-fish' transgenic common carp relative to their non-transgenic counterparts was due to their increased feed intake, reduced lose of waste productions and improved feed efficiency. The benefit of the increased energy intake by transgenic fish, however, was diminished by their increased metabolism.

Effect of dietary cyanobacteria on growth and accumulation of microcystins in Nile tilapia (Oreochromis niloticus)

A 12-week growth trial was conducted in a flow-through system to investigate the chronic toxic effect of dietary intake of cyanobacteria on growth, feed utilization and microcystins accumulation in Nile tilapia (Oreochromis niloticus L.) (initial body weight: 5.6 g). Six isonitrogenous and isocaloric diets were formulated to include different contents of cyanobacteria with the dietary microcystins increasing from 0 to 5460.06 ng/g diet. The results showed that dietary intake of cyanobacteria could increase the growth of tilapia while there are no impacts on feed conversion efficiency or mortality. Feeding rate was higher for the diets containing highest cyanobacteria. Microcystins were mostly accumulated in fish liver. The relationship between microcystins contents in muscle, liver, spleen and dietary intake could be described by quadratic equations. Microcystins content in the muscle of Nile tilapia in present study exceeded the upper limit of the tolerable daily intake (TDI) of microcystins suggested by the WHO (0.04 mu g/kg body weight/d). It is suggested that Nile tilapia fed on toxic cyanobacteria is not suitable for human food. (c) 2006 Elsevier B.V. All rights reserved.

Effects of the "all-fish" growth hormone transgene expression on non-specific immune functions of common carp, Cyprinus carpio L.

This study investigated non-specific immune functions of the F-2 generation of "all-fish" growth hormone transgenic carp, Cyprinus carpio L. Lysozyme activity was 145.0 (+/- 30.7) U ml(-1) in the transgenic fish serum and 105.0 (+/- 38.7) U ml(-1) in age-matched non-transgenic control fish serum, a significant difference (P < 0.01). The serum bactericidal activity in the transgenics was significantly higher than that in the controls (P < 0.05), with the percentage serum killing of 59.5% (6.83%) and 50.8% (8.67%), respectively. Values for leukocrit and phagocytic percent of macrophages in head kidney were higher in transgenics than controls (P < 0.05). However, the phagocytic indices in the transgenics and the controls were not different. In addition, the mean body weight of the transgenics was 63.4 (6.65) g, much higher than that of the controls [39.2 (+/- 3.30) g, P < 0.01]. The absolute weight of spleen of the transgenics [0.13 (+/- 0.03) g] was higher than that of the controls [0.08 (+/- 0.02) g, P < 0.01]. However, there was no difference in the relative weight of spleen between the transgenics and the controls, with the spleen mass index being 0.21% (+/- 0.02%) and 0.20% (+/- 0.03%), respectively. This study suggests that the "all-fish" growth hormone transgene expression could stimulate not only the growth but also the non-specific immune functions of carp. (c) 2006 Published by Elsevier B.V.

Meat and bone meal replacement in diets for juvenile gibel carp (Carassius auratus gibelio): effects on growth performance, phosphorus and nitrogen loading

A 11-week growth trial was conducted in a flow-through system with juvenile gibel carp Carassius auratus gibelio to evaluate the effects of gradual replacement of fish meal (FM) by meat and bone meal (MBM) on growth performance, phosphorus (P) and nitrogen (N) loading. Six isonitrogenous (crude protein: 410 g kg(-1)) and isoenergetic (gross energy: 18 kJ g(-1)) diets were formulated. FM was used as the control protein. In the other five diets, 20, 40, 60, 80 and 100% FM protein was substituted with MBM20, MBM40, MBM60, MBM80, MBM100, respectively. Total P content in the diets ranged from 16.0 to 28.3 g kg(-1) and the available P was 5.0-6.6 g kg(-1). The results showed that the best growth was achieved with fish fed on the control diet and MBM20. Final body weight, weight gain, feed efficiency, protein retention efficiency and energy retention efficiency decreased with increased dietary MBM. No significant differences were found in the feeding rate and hepatosomatic index between the groups. Apparent digestibility coefficient (ADC) of dry matter, protein and P decreased with increase in dietary MBM, while there were no significant differences in the ADC of energy. P and N retention decreased linearly while P and N loading increased linearly with the increased dietary MBM levels. No significant differences were observed in the activity of alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase, as well as pyruvate kinase in liver or in serum. Total superoxide dismutase activity in MBM20 was significantly higher than that of MBM100.

Effect of inclusion of blue-green algae meal on growth and accumulation of microcystins in gibel carp (Carassius auratus gibelio)

Six isonitrogenous (crude protein content: 38%) and isoenergetic (gross energy content: 17 kJ g(-1)) diets were formulated to investigate the effects of inclusion of blue-green algae meal on gibel carp (Carassius auratus gibelio). In each diet, 15% of the protein was supplied by fishmeal; the remainder was supplied by soybean meal and blue-green algae meal. Diet 1 was used as control with no blue-green algae meal whereas the content in diets 2-6 was 15.15, 29.79, 44.69, 59.58 and 74.48%, respectively. Each diet was fed to five groups of gibel carp for 12 weeks in a flow-through system. Final body weight and specific growth rate (SGR) of fish fed diet 5 were significantly lower than the control diet (P < 0.05). Mortality of gibel carp increased with increase in algae meal inclusion (P < 0.05), but there was no significant difference between fish fed diets 3-6 (P > 0.05). Feed conversion efficiency (FCE) decreased with the increase in algae meal inclusion (P < 0.05). Fish-fed diet 6 showed the highest feeding rate (P < 0.05), while there were no significant differences among the other groups (P > 0.05). Apparent digestibility coefficient of dry matter, protein, and energy decreased with increasing algae meal inclusion in the diets (P < 0.05). Aspartate aminotransferase (GOT) activity in the liver was not significantly different among groups (P > 0.05). Liver alanine aminotransferase (GPT) activity of fish-fed diets 4, 5 and 6 was significantly lower than the control diet (diet 1; P < 0.05). Microcystins in the muscle, liver, gallbladder, and spleen increased with increasing algae inclusion (P < 0.05).

Effect of dietary carbohydrate sources on growth performance and utilization for gibel carp (Carassius auratus gibelio) and Chinese longsnout catfish (Leiocassis longirostris Gunther)

The nutritional function of monosaccharides, disaccharides and polysaccharides for omnivorous gibel carp and carnivorous Chinese longsnout catfish were investigated and the ability of these two species to utilize carbohydrates was compared. For each species, triplicate groups of fish were assigned to each of five groups of isoenergetic and isonitrogenous experimental diets with different carbohydrate sources: glucose, sucrose, dextrin, soluble starch (acid-modified starch) and alpha-cellulose. The carbohydrates were included at 60 g kg(-1) in Chinese longsnout catfish diets and at 200 g kg(-1) in gibel carp diets. A growth trial was carried out in a recirculation system at 27.8 +/- 1.9 degrees C for 8 weeks. The results showed that fish with different food habits showed difference in the utilization of carbohydrate sources. For gibel carp, better specific growth rate (SGR) and feed efficiency (FE) were observed in fish fed diets containing soluble starch and cellulose, but for Chinese longsnout catfish, better SGR and FE were observed in fish fed diets containing dextrin and sucrose. Apparent digestibility coefficient of dry matter (ADC(d)) and apparent digestibility coefficient of energy (ADC(e)) were significantly affected by dietary carbohydrate sources in gibel carp. ADC(d) and ADC(e) significantly decreased as dietary carbohydrate complexity increased in Chinese longsnout catfish except that glucose diet had medium ADC(d) and ADC(e). In both species, no significant difference of apparent digestibility coefficient of protein was observed between different carbohydrate sources. Dietary carbohydrate sources significantly affected body composition, and liver phosphoenolpyruvate carboxykinase (PEPCK), pyruvate kinase (PK), glucose 6-phosphate dehydrogenase (G6PD) and malic enzyme (ME) activities also varied according to dietary carbohydrate complexity. Fish with different food habits showed different abilities to synthesize liver glycogen, and the liver glycogen content in gibel carp was significantly higher than in Chinese longsnout catfish. The influence of carbohydrate source on gluconeogenesis and lipogenesis was also different in the two fish species.

Distribution, feeding and body condition of four small fish species in the near-shore and central areas of Liangzi Lake, China

Small fish abundance is usually high in heavily vegetated habitats in Yangtze lakes, China. Visual and swimming barriers created by dense macrophytes beds could reduce feeding efficiency and growth of small fishes. We tested the hypothesis that small fishes in habitats with dense macrophytes would show decreased feeding efficiency and reduced growth rates by comparing feeding efficiency (measured as the relative weight of fore-gut contents), total length, and condition factor of four small young-of-the-year fishes collected in the near-shore (heavily vegetated) and central (less vegetated) areas of Liangzi Lake. Feeding efficiency, total length, or condition factor were each significantly reduced in the near-shore area compared with the central area for Ctenogobius giurinus, Pseudorasbora parva and Carassius auratus auratus. This supports our hypothesis that vegetation abundance may mediate feeding efficiency and growth of small fishes. Although Hypseleotris swinhonis did not show significant decreases in feeding efficiency or growth in the near-shore area, there was not any reversed tendency, i.e. increased feeding rate or growth in the near-shore area compared to the central area.

Partial compensatory growth in hybrid tilapia Oreochromis mossambicus x O-niloticus following food deprivation

The capacity of hybrid tilapia Oreochromis mossambicus x O. niloticus [23.2 +/- 0.2 g (mean +/- SE)] to show compensatory growth was assessed in an 8-week experiment. Fish were deprived of feed for 1, 2 and 4 weeks, and then fed to satiation for 4 weeks; fish fed to satiation during the experiment served as control. Water temperature gradually declined from 28.1 to 25.5 degrees C throughout the experiment. Specific growth rate (SGR) decreased with progressive food deprivation. At the end of deprivation, body weight was lower in the deprived fish than in the control. Fish deprived for 4 weeks exhibited lower contents of lipids and energy in whole body, and higher moisture content and ratio of protein to energy (P/E) than those of the control; they also consumed feed faster than the control when normal feeding was resumed. All deprived fish showed higher food intake (FI) than that of the control during re-alimentation; however, enhanced SGR was only observed in the fish deprived for 4 weeks. There were no significant differences in digestibility of protein and energy, food efficiency (FE) or energy retention efficiency between the control and deprived fish. At the end of re-alimentation, deprived fish failed to catch up in body weight with the control, while content of moisture, lipids and energy, and P/E in whole body of the deprived fish did not significantly differ from that of the control. The results of the experiment revealed that the hybrid tilapia reared in freshwater showed partial capacity for compensatory growth following food deprivation of 4 weeks, and that growth compensation was due mainly to increased FI, rather than to improved FE.

Effects of live food and formulated diets on survival, growth and protein content of first-feeding larvae of Plelteobagrus fulvidraco

In recent years, much progress has been made in the rearing of fish larvae fed only artificial diets. A preliminary study was made in an attempt to evaluate the effects of live food and formulated diets on survival, growth and body protein content of first-feeding larvae of Plelteobagrus fulvidraco. Three test diets varying in protein level were formulated: Feed 1 containing 45% protein, Feed 2 with 50% protein and Feed 3 with 55% protein. Larvae fed live food (newly hatched Artemia, unenriched) were the control. The experiment started 3 days post-hatch and lasted for 23 days. At the end of the 23-day trial, survival was best in the control group (65.6%) whereby the final body weight and specific growth rate (SGR) were significantly lower than those in the test feed groups. At the same time, coefficients of variation for SGR and final body weight in the test groups were significantly higher than those in the control. Whole body protein content in all treatments showed a similar tendency during development: significantly higher 3 days post-hatch, then decreasing significantly, and then increasing unstatistically 10 days post-hatch. All results suggest that live food is still better for first-feeding larvae of P. fulvidraco, since live food leads to healthier larvae growth.

Compensatory growth and food consumption in gibel carp, Carassius auratus gibelio, and Chinese longsnout catfish, Leiocassis longirostris, experiencing cycles of feed deprivation and re-feeding

The compensatory responses of juvenile gibel carp and Chinese longsnout catfish to four cycles of 1 part of a study designed to determine feeding regimes that would maximise growth rates. Both species showed compensatory growth in the re-feeding periods. The compensation was not sufficient for the deprived fish to match the growth trajectories of controls fed to satiation daily. The compensatory growth response was more clearly defined in the later cycles. The deprived fish showed hyperphagia during the 2-week periods of re-feeding and the hyperphagic response was clearer in the later cycles. The hyperphagia tended to persist for both weeks of the re-feeding period. The gibel carp showed no difference in gross growth efficiency between deprived and control fish. In the catfish, the gross growth efficiency of the deprived fish was marginally higher than that of control fish, but the efficiency varied erratically from week to week. Over the experiment, the deprived fish achieved growth rates 75-80% of those shown by control fish, although fed at a frequency of 66%. There was no evidence of growth over-compensation with the deprivation-re-feeding protocol used in this study. (C) 2004 Elsevier B.V. All rights reserved.

Enhanced robotic body extension with modular units

The adaptation of robots to changing tasks has been explored in modular self-reconfigurable robot research, where the robot structure is altered by adapting the connectivity of its constituent modules. As these modules are generally complex and large, an upper bound is imposed on the resolution of the built structures. Inspired by growth of plants or animals, robotic body extension (RBE) based on hot melt adhesives allows a robot to additively fabricate and assemble tools, and integrate them into its own body. This enables the robot to achieve tasks which it could not achieve otherwise. The RBE tools are constructed from hot melt adhesives and therefore generally small and only passive. In this paper, we seek to show physical extension of a robotic system in the order of magnitude of the robot, with actuation of integrated body parts, while maintaining the ability of RBE to construct parts with high resolution. Therefore, we present an enhancement of RBE based on hot melt adhesives with modular units, combining the flexibility of RBE with the advantages of simple modular units. We explain the concept of this new approach and demonstrate with two simple unit types, one fully passive and the other containing a single motor, how the physical range of a robot arm can be extended and additional actuation can be added to the robot body. © 2012 IEEE.

Effect of replacement of dietary fish meal by meat and bone meal and poultry by-product meal on growth and feed utilization of gibel carp, Carassius auratus gibelio

Triplicate groups of gibel carp Carassius auratus gibelio (initial body weight: 5.25 +/- 0.02 g) were fed for 8 weeks at 20-25 degreesC on five isonitrogenous (crude protein: 400 g kg(-1)) and isoenergetic diets (gross energy: 17 kJ g(-1)). Meat and bone meal (MBM) or poultry by-product meal (PBM) were used to replace fish meal at different levels of protein. The control diet contained fish meal as the sole protein source. In the other four diets, 150 or 500 g kg(-1) of fish meal protein was substituted by MBM (MBM15, MBM50) or PBM (PBM15, PBM50). The results showed that feeding rate for the MBM50 group was significantly higher than for other groups except the PBM50 group (P < 0.05). Growth rate in the MBM15 group was significantly higher than that in the control (P < 0.05), while there was no significant difference in growth between the control and other groups (P > 0.05). Feed efficiency and protein efficiency ratio in MBM50 was significantly lower while that in MBM15 was significantly higher (P < 0.05). Replacement of fish meal by MBM at 500 g kg(-1) protein significantly decreased apparent dry matter digestibility (ADC(D)) and gross energy (ADC(E)) while apparent protein digestibility (ADC(P)) was significantly decreased by the replacement of MBM or PBM (P < 0.05). The results suggest that MBM and PBM could replace up to 500 g kg(-1) of fish meal protein in diets for gibel carp without negative effects on growth while 150 g kg(-1) replacement by MBM protein improved feed utilization.

Comparative study on the effect of dietary lipid level on growth and feed utilization for gibel carp (Carassius auratus gibelio) and Chinese longsnout catfish (Leiocassis longirostris Gunther)

An 8-week growth trial investigated the effect of dietary lipid level on growth performance of a carnivorous fish, Chinese longsnout catfish (Leiocassis longirostris Gunther) and an omnivorous fish, gibel carp (Carassius auratus gibelio). For each species, seven isonitrogenous semi-purified diets (455 g kg(-1) crude protein for Chinese longsnout catfish and 385 g kg(-1) crude protein for gibel carp) were formulated to contain 30, 60, 90, 120, 150, 180 or 210 g kg(-1) lipid. For Chinese longsnout catfish, feed intake (FI) decreased with increasing dietary lipid and there was no significant difference in feed intake from 90 to 210 g kg(-1) lipid. Specific growth rate (SGR) increased with dietary lipid level (P < 0.05) and the 150 and 180 g kg(-1) groups were the best. Feed conversion efficiency (FCE), protein retention efficiency (PRE) and energy retention efficiency (ERE) were higher at 180 g kg(-1) lipid. For gibel carp, FI decreased with increased dietary lipid and 180 and 210 g kg(-1) lipid groups showed lower values. SGR increased with dietary lipid level and the 150 and 180 g kg(-1) were the best. FCE was higher at 180 g kg(-1) lipid level. PRE increased with dietary lipid level and there was no significant difference in groups from 120 to 210 g kg(-1) dietary lipid. ERE increased with increasing dietary lipid level, and groups fed 120, 150 and 180 g kg(-1) lipid showed the highest values. In Chinese longsnout catfish, increase in dietary lipid level, resulted in increased carcass dry matter, crude protein, crude lipid and gross energy. In gibel carp, dry matter, crude protein, and crude lipid increased with dietary lipid level. Based on regression between SGR and dietary lipid, dietary lipid requirements for Chinese longsnout catfish and gibel carp were 142.6 and 140.5 g kg(-1), respectively.

Effect of replacement of fish meal by meat and bone meal and poultry by-product meal in diets on the growth and immune response of Macrobrachium nipponense

The potential use of poultry by-product meal (PBM) and meat and bone meal (MBM) as alternative dietary protein sources for juvenile Macrobrachium nipponense was studied by a 70-day growth trial. Triplicate groups of M. nipponense (initial body weight: 0.37 g) were fed at 20.7-22.4 degreesC on each of the five isoenergetic and isonitrogenous diets (protein content about 38%) with different replacement of fish meal by MBM or PBM. The control diet used white fish meal as the sole protein source, the other four diets were prepared with 15% or 50% fish meal protein substituted by either MBM (MBM15, MBM50) or PBM (PBM15, PBM50). The results showed that replacement of fish meal by MBM in diets did not affect growth performance of M. nipponense (P > 0.05), while specific growth rate in PBM15 was significantly higher than that in other groups (P < 0.05). Survival rates of shrimp fed with MBM15 diet were significantly higher than that in other groups (P < 0.05). No significant differences in immunological parameters, including total haemocyte count (THC), phenoloxidase activity (PO) and respiratory burst (O-2(-)), were observed between the shrimps that were fed five experimental diets, and all determined immunological parameters in control groups were slightly higher than those in replacement groups. In conclusion, either MBM or PBM investigated could replace up to 50% fish meal protein in diets for M. nipponense. (C) 2003 Elsevier Ltd. All rights reserved.

Effect of ration on the growth and energy budget of Chinese longsnout catfish, Leiocassis longirostris Gunther

The effect of ration on growth and energy budget of Chinese longsnout catfish was investigated in a growth trial. Fish of initial body weight of 6.5 g were fed at six ration levels (RLs): starvation, 0.8%, 1.6%, 2.4%, 3.2% of body weight per day, and apparent satiation for 8 weeks. Fish were weighed biweekly to adjust feed amount. The results showed that specific growth rate in wet weight, protein and energy increased logarithmically with increased RLs. The relationship of specific growth rate in wet weight (SGRw, % day(-1)) and RL (%) was a decelerating curve: SGRw=-0.62+3.10 Ln(RL+1). The energy budget equation at satiation was: 100 IE=12.94 FE+5.50(ZE+UE)+40.07 HE+41.49 RE, where IE, FE, (ZE+UE), HE, RE are food energy, faecal energy, excretory energy, heat production and recovered energy respectively. Body composition was slightly but significantly affected by ration size except for protein content. The most efficient ration based on the relationship between RL and feed efficiency ratio in energy (FERe) was 1.8% of body weight per day.