Boxfish Research Articles

Gross Anatomy and Histological Features of Gymnarchus niloticus (Cuvier, 1829) from the River Niger at Agenebode in Edo State, Nigeria

This study was conducted to record the anatomy and histological features of the gastrointestinal tract of the trunk fish Gymnarchus niloticus captured at Agenebode in the Lower River Niger, Edo State. The gastrointestinal tract was segmented into the mouth, oesophagus, stomach, pyloric caeca, and intestine. The slender (taeniform) body that is fuller at the head tappers at its end. There are no spines on this fish, and the fins used for locomotion are the dorsal fins and not the typical pectoral fins as in other fish. The oesophagus, stomach, pyloric caeca, intestine, and cloaca (anterior, intermediate, posterior, and rectum) were analysed for histological examination. The stomach had significantly higher villi and thicker inner circular muscles compared to the intestine and oesophagus. The lamina propria was thickest in the stomach which is significantly higher when compared with the oesophagus, but not with the intestine. However, the intestine showed significantly thicker outer longitudinal muscle, while gastric glands were observed only in the stomach. The histological features were closely associated with the functions of the different segments of the gastrointestinal tract. In conclusion, the histological features of the gastrointestinal tract of G. niloticus are consistent with the feeding habit of a carnivorous fish. In conclusion, the GIT is a complex structure composed of organs that reveals that it is a higher vertebrate created for a hardy survival, consistent with the feeding habit of a carnivorous fish. The histology reveals a GIT formed by four conspicuous layers from the inside to the outside of the mucosa, submucosa, and an inner longitudinal layer of the muscularis and the outer circular of the muscularis typical of higher vertebrates.

Determinants of consumers’ choice behaviour for fresh fish types

The demand for and supply of fresh fish in many developing countries in the world today Nigeria inclusive, are yet to satisfy the annual dietary needs of their citizenry. This phenomenon, therefore, put unresisting pressure on the need to identify and grow more fresh fish that can meet the socio-cultural and economic desires of consumers. In the light of this, the present study examines the determinants of consumers’ choice behaviour for fresh fish types in Nigeria. Primary data were collected from 360 household heads through a structured questionnaire using a multistage sampling procedure. Multinomial logit regression model (MNL) was employed to analyse the impacts of socio-economic and fish-specific attributes of consumer choice for fresh fish. Results showed that 81 per cent were female households with a mean age of 35 years and mean household size of 4 members. Mean years of schooling and monthly expenditure were 13 and ₦3,611.94 (USD10.01), respectively. Mean consumptions of fresh fish category were mudfish (0.3354), catfish (0.1889), tilapia (0.2167), trunk fish (0.1138) and snakehead fish (0.1444). The McFadden R2 was 0.50 and the validity of independence of irrelevant alternatives hypothesis for the use of MNL was not violated given a p-value of 0.7618. Results showed that consumers' income, price of the fish, level of education, household size, experience and freshness had a significant impact on fresh fish choices. The study therefore recommends that policy that will increase consumers’ satisfaction for every naira spent on fresh fish and improve fish qualities should be given proper attentions.

Budidaya Ayam-Ikan Terintegrasi Dalam Pembangunan Ekonomi Masyarakat Desa Nyogan Kecamatan Mestong

Abstract
 The aim of the service activity was to develop the economy of Nyoga Community through the cultivation of integrated fish broiler.Due to the successfulness of the previous service program in year 2017 concerning the cultivation of Tilafia and catfish with farmer group (Kelompok Usaha Bersama (KUBE)) Mina Jaya dan Harapan Makmur in Nyogan village, the next program was to tried to apply the cultivation program of integrated fish and broiler by participation method from all of members of KUBE. Like previous program, the method was to involve all the group member of KUBE. Group member prepared the chicken pen above the fish pond and service team from University of Jambi granted the breed of fish and chicken. The result showed the good achievement with the increase of community interest of the KUBE to self-financingly build more unit of box fish nets
 Keyword : Nyogan, catfish, tilafia, integrated system, broiler

“FISH BOX PERLTIER COOLER” FISH COLLING BOX EQUIPPED WITH PELTIER ELECTRIC COOLER (PEC)

The Purpose The purpose of this study is to provide solutions of SMEs D.SadewaKenjeran Beach related to traditional storage of marine fish products that is still using ice cubes as a cooler in the box of fishes storage. Method The method used by using Peltier Electric Cooler (PEC) in the box of fishes storage to produce stable temperature. The PEC box control system is equipped with Arduino and programmed with CX programmer. It is designed to accommodate 15kg of fish per process. Result The expected result is to improve the stability of the cooling process (below 100C), the growth of bacteria will be slower so that the product can last longer. So the productivity of SMEs can be increased 2 times with the capacity of box 15 kg of fishes. The Finding The findings of this study are the usage of 15 kg PEC box fish with Arduino CX Programmer temperature control system as a solution of storage problems of marine fish products. Keywords :Peltier Electric Cooler (PEC), SMEs, Box, Fish

Evaluation of pesticides residues distribution in fresh and smoked body parts of Clarias gariepinus and assessment of possible health risks in Nigeria

Pesticides residues in fresh and smoked body parts of Clarias gariepinus were investigated to evaluate their contamination status and risks to human health. The results gave an overview of the contamination levels of these (head, body trunk and liver) fish parts. The pesticides [organochlorine (OC), organophosphorus (OP), pyrethroids (PY) and others like: guazatine, methoprene, metalaxyl and imidachloprid] concentration in the fresh and smoked body parts ranged from 0.002 to 0.221 µg/kg and 0.002 to 0.175 µg/kg, with mean concentration of 0.002–0.218 µg/kg and 0.002–0.126 µg/kg, respectively. Smoking was observed to reduce the overall pesticide concentration as follows: head (0.23 µg/kg or 17.3%), liver (0.34 µg/kg or 29.8%) and muscles (0.41 µg/kg or 27.2%). The pesticides contents were significantly lower than standard daily intake and the risk associated with consumption of the fish also showed that the fish posed no potential threat to consumers.

CFD Analysis for Merdeka 2 Solar Vehicle

Vehicle's low drag force is critical to achieve higher speed and for efficient energy usage. Most solar vehicles that participated in the World Solar Challenge event adopted the 'cockroach' shape which has been considered as the best shape to achieve optimum speed and aerodynamics characteristics. However, the team from University of Malaya decided to design their entry vehicle based on the profile of a box fish, said to possess an even lower drag coefficient value. This paper describes the aerodynamics characteristics numerical study of the solar vehicle using a computational fluid dynamics (CFD) code called FLUENT. The numerical computation is based on the frontal area of the vehicle and the obtained results have shown reasonable values of drag and lift coefficients when compared to ordinary road vehicles.

Establishment of a biomimetic device based on tri-layer polymer actuators—propulsion fins

We propose to use bending type tri-layer polymer actuators as propulsion fins for a biomimetic device consisting of a rigid body, like a box fish having a carapace, and paired fins running through the rigid body, like a fish having pectoral fins. The fins or polymer bending actuators can be considered as individually controlled flexible membranes. Each fin is activated with sinusoidal inputs such that there is a phase lag between the movements of successive fins to create enough thrust force for propulsion. Eight fins with 0.125 aspect ratio have been used along both sides of the rigid body to move the device in the direction perpendicular to the longitudinal axis of the body. The designed device with the paired fins was successfully tested, moving in an organic solution consisting of solvent, propylene carbonate (PC), and electrolyte. The design procedure outlined in this study is offered as a guide to making functional devices based on polymer actuators and sensors.

Sugar Codes for Axons?

Proteoglycans are complex macromolecules with the potential for extraordinary diversity. Several recent studies have demonstrated important roles for heparan sulfate and chondroitin sulfate proteoglycans (HSPGs and CSPGs) in axon pathfinding and have linked HSPGs to specific signaling pathways. More speculatively, there are hints of a "sugar code," in which specific sugar modifications might act instructively in guidance decisions. This raises the intriguing possibility that the complexity of neuronal wiring may in part reflect the complexity of proteoglycan modifications.

Heavy metals in commercial fish of Ogun River at Abeokuta, Nigeria

AbstractSilver catfish, silverside fish, Nile tilapia and trunk fish caught near Abeokuta, contained Cu, Fe, Mn, Pb and Zn below the maximum acceptable level recommended by FAO for human consumption. Copyright © 2004 Whurr Publishers Ltd

Factors regulating the height of spawning ascents in trunkfishes (Ostraciidae)

Factors regulating the height of spawning ascents in trunkfishes (Ostraciidae)

Effects of mesh covers on the growth and survival of silver-lip pearl oyster ( Pinctada maxima, Jameson) spat

Spat of the silver-lip (or gold-lip) pearl oyster, Pinctada maxima, were re-settled onto PVC slats at a mean density of 340 per 100 cm 2. Spat had a mean (±s.e.) dorso-ventral shell height and antero-posterior shell length of 1.2±0.3-mm and 1.8±0.5-mm, respectively. The PVC slats were either left exposed (control) or covered with a mesh sleeve of varying aperture sizes (0.75, 1.5 or 3.0-mm) before being transferred to an ocean-based suspended nursery culture system. After two weeks of nursery culture, there was no significant difference ( P>0.05) among the number of spat retained on the covered slats; however, all covered slats had significantly greater ( P<0.001) spat retention than the control which had fewer than 1 spat per 100 cm 2. Some of the spat in the control treatment may have been eaten by box fish (Ostraciidae) and file fish (Monacanthidae) which were observed pecking at the exposed PVC slats. Shell height and shell length increased significantly ( P<0.05) with each increase in mesh size. The remaining spat on the control slats were smaller than the mean size of the spat at the start of the trial although this difference was not significant ( P>0.05). This probably resulted from fish and other predators preferentially attacking the larger individuals. There was no advantage in using sleeves with a mesh size small enough to retain dislodged spat. The majority of dislodged spat in the 0.75-mm and 1.5-mm mesh sleeves perished when they fell into the corners of the sleeve whereas most dislodged individuals were small enough to fall through the 3.0-mm mesh sleeve. A 3.0-mm mesh is appropriate to house spat of the size used in this study. Smaller mesh sizes, while not affecting survival, fouled more rapidly and resulted in reduced spat growth.

Vibrindole A, a Metabolite of the Marine Bacterium, Vibrio parahaemolyticus, Isolated from the Toxic Mucus of the Boxfish Ostracion cubicus

The EtOAc extract of the whole culture medium of Vibrio parahaemolyticus, which inhabits the toxic mucus of the box fish Ostracion cubicus, afforded a new indole-derived natural product, vibrindole A [1], along with some known cyclic dipeptides and indoles. The structure of 1 was determined by analysis of its physicochemical characteristics.

New Genus and Species of Boxfish (Tetraodontiformes: Ostraciidae) from the Oligocene of Moravia, the Second Fossil Representative of the Family

New Genus and Species of Boxfish (Tetraodontiformes: Ostraciidae) from the Oligocene of Moravia, the Second Fossil Representative of the Family

An Indo‐Pacific trunkfish Tetrosomus gibbosus (Linnaeus): first record of the family Ostracionidae in the Mediterranean

An Indo‐Pacific trunkfish <i>Tetrosomus gibbosus</i> (Linnaeus): first record of the family Ostracionidae in the Mediterranean

Early Growth and Quality of Chum Salmon (Oncorhynchus keta) Produced in Keeper Channels and Gravel Incubators

Chum larvae were incubated in two types of incubation system — a pilot Japanese-style hatchery (JSH) and a set of deep-gravel incubators (box) — at two levels of flow and two, or three, levels of egg density. Following voluntary emergence, fish were reared in tanks on an OMP diet and their growth rates compared. Initially, fry from both systems were of the same average size, but the JSH fish emerged 6 d earlier than the box fish and at a stage of development 6 d less advanced. At the end of 8 wk, all JSH groups were significantly longer than the box groups; the most extreme groups averaged 63.4 and 59.2 mm, respectively. Not only had the JSH fish kept their 6-d lead in additional growth, but they also grew significantly faster (calculated average rates were 3.553 and 3.217 mm/wk in the above groups). A previous assessment of fry quality had rated the JSH fry inferior to the box fry on the basis of four criteria (efficiency of yolk conversion, size and stage of development at emergence, and time of emergence). In this test, however, JSH fry rated superior in terms of final size and rate of growth achieved during 8 wk following emergence. Difficulties with simplistic quality criteria and how such criteria relate to fitness are discussed.