10 research outputs found
The influence of light wavelength and intensity to the survival rates, growth rates and production index of Sutchi Catfish larvae
Sutchi catfish Pangasianodon hypophthalmus (Sauvage, 1878) is one of the most important freshwater fish species cultured in Southeast Asia. Artificial seed production of
sutchi catfish is very important in aquaculture industry. However, the larval survival rates were low when reared in the hatchery. Providing optimum rearing condition for sutchi
catfish larvae in the hatchery can increase the seeds production. Light conditions was reported to influence the survival and growth of fish. Hence, this study was conducted to examine the optimum light conditions in term of light wavelength and light intensity for rearing of sutchi catfish larvae. The sutchi catfish larvae were reared under five different light wavelengths (white, blue, green, yellow and red lights) and four different light intensities (1.40 10-4
, 1.40 10-3 , 1.40 10-2 , and 1.40 10-1 µmol/m²/s). The results
showed that, the survival rates (SR), growth rates (SGRTL and SGRBW) and Production Index (PI) were higher in red light than other wavelengths. For light intensity, only PImshown significant effect to the larvae. Light intensity of 1.40×10-3 µmoles/m²/s wasmsignificantly higher than 1.40×10-1 µmoles/m²/s intensity. Apart from that, there weremtendency for high SR, SGRTL and SGRBW under low light intensities (1.40 10-4m and 1.40 10-3
µmoles/m²/s) when compared to high light intensities (1.40 10-2, and 1.40 10-1 µmol/m²/s). Therefore, red light wavelength and low light intensities (1.40 10- 4 and 1.40 10-3 µmoles/m²/s) were recommended when rearing sutchi catfish larvae
High growth rate using new type demand feeding system with image processing program and fish behavior.
Demand feeding system serves feeds to fish, when fish switch on feeders. Although demand feeding system has advantages, it still has problems, e.g. hierarchy problem
of fish school and system learning period problem for fish. New type of demand feeding system was develop to solve these problems using fish behaviour and image
processing system. At first, behaviour experiment was conducted using the image processing software Roborealm to obtain the optimum parameter for computer program. Through the behaviour experiment, two typical behaviour patterns were detected. When fish was hungry, fish group came to the water surface (H: parameter >63%), and when fish was not hungry, fish came to bottom (L: <45%) of fish tank. These two parameters were obtained and were put into the computer program in the workstation. HD Wi-Fi camera continuously recorded the real time fish behaviour in fish
tank, and when fish group came to above the “H”, then the command was sent from workstation to microcomputer to send the order to feeding device to feed on. The results of feeding experiment showed this system could provide pellets to fish day and night time equally following fish behaviour. This feeding system could provide the
pellets to fish based on fish requirements. The growth rate was higher than other feeding system (timer feeder and demand feeder using an infrared light sensor)
Cannibalistic behaviour of Sutchi catfish (Pangasianodon hypophthalmus) larvae under different light conditions
Sutchi catfish Pangasianodon hypophthalmus larvae have high mortality rate in hatchery because of strong cannibalism. Many factors were influencing the cannibalism rate. One of them is light condition. In previous study, the sutchi catfish larvae show higher mortality in bright light condition than in dim light condition under white fluorescent lamp (Mukai, 2011). So far, there were no study conducted about the effect of different light wavelengths on the sutchi catfish larvae. In this study, the cannibalistic behaviours of sutchi catfish larvae was investigated under different light wavelengths (white, blue, green, yellow and red) and light intensities (0.0014, 0.014, 0.14 and 1.4 μmol m-2 s-1). Ten larvae (4-14 days old) were placed in a glass basin under different light conditions in a dark room. The behaviours of the larvae were recorded for 30 minutes after adaptation. The cannibalistic behaviours (biting, resting and swimming activity) of the larvae were analysed from the video recorded
The optimum light condition for Sutchi catfish larval rearing
Sutchi catfish Pangasianodon hypophthalmus (Sauvage, 1878) is one of the most important freshwater fish species cultured in Southeast Asia. Artificial seed production of sutchi catfish is very important in the aquaculture industry. However, the larval survival rates were low when reared in the hatchery. Providing optimum rearing condition for sutchi catfish larvae in the hatchery can increase the seeds production. The light condition was reported to influence the survival and growth of fish.
Hence, this study was conducted to examine the optimum light condition in term of light wavelength and light intensity for sutchi catfish larval rearing. The sutchi catfish larvae were reared under five different light wavelengths (white, blue, green, yellow and red lights) and four different light intensities (1.40×10-4 , 1.40×10-3 , 1.40×10-2
, and 1.40×10-1 µmol/m²/s). The results showed that the
survival rates (SR), growth rates (SGRTL and SGRBW) and production index (PI) were higher in red light than other wavelengths. For light intensity, only PI showed a significant effect on the larvae. Light intensity of 1.40×10-3 µmol/m²/s was significantly higher than 1.40×10-1 µmol/m²/s intensity. Apart from that, there was a tendency for high SR, SGRTL and SGRBW under low light intensities (1.40×10-4 and 1.40×10-3 µmoles/m²/s) when compared to high light intensities (1.40×10 -2
, and 1.40×10-1 µmol/m²/s). Therefore, red light wavelength and low light intensities (1.40×10 -4 and
1.40×10-3 µmoles/m²/s) were the optimum light condition for sutchi catfish larval rearing
Influence of light wavelength and intensity on the survival and somatic growth of the early larval stage of sutchi catfish Pangasianodon hypophthalmus
The present study examined the influence of various light wavelengths and intensities on the survival and somatic growth of sutchi
catfish Pangasianodon hypophthalmus larvae during their most critical period. Two-day-old larvae (initial total length, TLi = 3 mm; initial body
weight, BWi = 0.002 g) at a stocking density of 10 larvae per litre were reared in triplicate under five light wavelengths (white as a control,
blue, green, yellow and red wavelengths) of four light intensities (1.40×10-3, 1.40×10-2, 1.40×10-1 and 1.40 μmol/m²/s). The larvae showed a
tendency towards higher survival rates (SR) and production index (PI) under longer light wavelengths (yellow and red wavelengths) and at a
light intensity of 1.40×10-3 μmol/m²/s. Furthermore, the larvae reared under red wavelength showed a tendency towards higher specific
growth rates for both length and body weight (SGRL and SGRBW) than those reared under other light wavelengths. These findings provide
fundamental information regarding the optimum light conditions for larval rearing of sutchi catfish, as well as providing insight about the
adaptation of the larvae towards the environmental light in the wild
High growth rate and low feed conversion ratio using new type demand feeding system with image processing program and fish behavior
New type feeding system was developed to overcome the various problems related to feeding to fish. This system used fish behaviour as indicator to control feeding device. In general when fish are hungry, they show some attitudes that they are searching something or looks
twitchy. When fish are satisfied, their behaviour is different. In this system, CCD cameras detected fish behaviour and computer program analysed the differences of behaviour, then the programed decided and transmitted the order to feeding device to start feeding or stop feeding. This type feeding device is creative, unique and the first in the world. This system can solve various feeding problems and surely will make a
revolution in aquaculture
High growth rates of Asian seabass (Lates calcarifer Bloch, 1790) fry reared using a demand feeder with an image processing system for detecting fish behaviour
The feeding behaviour and growth rates of Asian seabass (Lates calcarifer Bloch,
1790) fry were studied using a new type demand (NTD) feeder. This feeding system
was equipped with a programme to detect hunger behaviour in fish and automatically
dispense pellets. This system could overcome hierarchy in fish during feeding.
Fish rearing experiments were conducted to compare the NTD feeder with infrared
light demand (ILD) and automatic timer (AT) feeders. The specific growth rate of body
weight (SGRBW) was significantly higher with the use of the NTD feeder than with the
ILD or AT feeders. The specific growth rate of total length (SGRTL) and feed conversion
ratios (FCR) showed no significant differences among the three types of feeders.
Fish feeding behaviour experiments were conducted, and the feeding frequencies
were compared. The average feeding frequency and feeding amount per day by the
NTD feeder were significantly higher than those by the ILD feeder. In the NTD feeder,
seabass ate small amounts of pellets with high frequencies at each feeding time.
Therefore, high frequency feeding could be one of the reasons for the high growth
rates of fish fed using the NTD feeder
Demand feeding system using image processing program and fish behavior
Fish feeding systems have three methods; manual, automatic and demand feeding. Demand feeding system serves feeds to fish, when fish switch on feeders. Although demand feeding system has advantages, it still has problems, e.g. small number fish occupy the actuation of the feeder switch, and it takes long time for fish to learn the feeding system. New type of demand feeding system was develop to solve these problems using fish behaviour and image processing system. At first, behaviour experiment was conducted using the image processing software Roborealm to obtain the optimum parameter for computer program. Through the behaviour experiment, two typical behaviour patterns were detected. When fish was hungry, fish group came to the water surface (H: parameter >63%), and when fish was not hungry, fish came to bottom (L: <45%) of fish tank. These two parameters were obtained and were put into the computer
program in the workstation. HD Wi-Fi camera continuously recorded the real time fish behaviour in fish tank, and when fish group came to above the “H”, then the command
was sent from workstation to microcomputer to send the order to feeding device to feed on. The results of feeding experiment showed this system could provide pellets to fish
day and night time equally following fish behaviour. This feeding system could provide the pellets to fish based on fish requirements. Thus, this system has a potential to realize
sustainable aquaculture
Demand feeding device using a video processing system and fish behavior as parameter for a computer program to control feeding time and amount
Fish feeding system has three methods; manual, automatic and demand feeding. Demand feeding system serves feeds to fish, when fish switch on feeders. Although demand feeding system has advantages, there are still some problems; e.g. social status in fish. A few fish occupy the actuation of switch of the feeder, so results show the variation in fish growth. Another issue is that the fish learning period of demand feeders becomes long depending on fish species.
New type feeding system was developed to overcome these problems related to feeding to fish. The new feeding system uses fish behaviour as sensor to control feeding device. In general when fish are hungry and not hungry, their behaviours are different. In this system, CCD cameras detected fish behaviour and computer program analysed the differences of behaviour, then the programed decided and transmitted the order to feeding device to start feeding or stop feeding. Asian seabass young were used for feeding test of this feeding system. Control experiments were prepared with timer feeder and infrared feeding system. Glass aquaria (45 cm x 45 cm x 90 cm) were prepared with each feeding system and water filtration system. Each system was prepared triplicate aquaria.
Feeding experiment results showed no significant difference among each feeding system, however the experiment showed the new feeding system could provide the feed to fish smoothly and it can be used for fish rearing
Hunger classification of Lates calcarifer by means of an automated feeder and image processing
In an automated demand feeder system, underlining the parameters that contribute to fish hunger is crucial in order to facilitate an optimised food allocation to the fish. The present investigation is carried out to classify the hunger state of Lates calcarifer. A video surveillance technique is employed for data collection. The video was taken throughout the daytime, and the fish were fed through an automated feeding system. It was demonstrated through this investigation that the use of such automated system does contribute towards a higher specific growth rate percentage of body weight as well as the total length by approximately 26.00 and 15.00, respectively against the conventional time-based method. Sixteen features were feature engineered from the raw dataset into window sizes ranging from 0.5�min, 1.0�min, 1.5�min and 2.0�min, respectively coupled with the mean, maximum, minimum and variance for each of the distinctive temporal window sizes. In addition, the extracted features were analysed through Principal Component Analysis (PCA) for dimensionality reduction as well as PCA with varimax rotation. The data were then classified using a Support Vector Machine (SVM), k-Nearest Neighbor (k-NN) and Random Forest Tree models. It was demonstrated that the varimax based PCA yielded the highest classification accuracy with eight identified features. The prediction results based of the developed k-NN model on the selected features on the test data exhibited a classification rate of 96.5 was achieved suggesting that the features examined are non-trivial in classifying the fish hunger behaviour