.png){kind=logo}
Research Article
Apr 25, 2018
Helminthiasis and Gram Negative Enteric Bacteria in Freshwater Fish from Selected Lakes of Haramaya ... District, Ethiopia
Microbiological and helminthiasis examination of fish from Tinike and Adelle Lakes were conducted at Haramaya District, Ethiopia. The types of fish available in the lakes were also assessed. Adelle Lake has only Clarias gariepinus while the Tinike Lake has only Oreochromis niloticus fish species. Ten fish of each species, 20 in total, were collected from the lakes and post-mortem examined for the presence of adult helminthiasis in the body parts. Twelve samples from different body parts of each fish, 240 samples in total, and 11 samples of lakes water were aseptically collected and examined for gram-negative enteric bacteria. No adult parasites were observed in fish from Adelle Lake. However, 15% and 20% of the fish from Tinike Lake had cestodes in their intestine, and nematodes in their heart respectively. Of 251 total samples from fish and the lake water, 178 (70.9%) were positive for pathogenic microbial. Except for muscle tissue to which only 5% are positive, 50% and above samples were found positive for some Gram’s-negative bacteria. From total of fish and water sample, 43%, 36.3%, 15.1%, 12.8%, and 1.2% are positive for Proteus, E. coli, Salmonella, Yersinia and Klebsiella respectively in the descending order. Two bacterial genera, Proteus and E. coli (13.6%), Proteus and Yersinia (2%), Proteus and Salmonella (4%), E. coli and Yersinia (2%), E. coli and Salmonella (1.2%), and E .coli and Klebsiella (0.4%) while triplet of genera Proteus, E. coli and Yersinia (6%), Proteus, E. coli and Salmonella (0.8%), and Proteus, E. coli and salmonella (0.4%) were observed. Salmonella spp. was not detected from fish from Lake Adelle compared to the 30% in fish from Lake Tinike (P<0.0001). Proper cooking of fish could destroy those spoilage and public health risk. Observing similar levels of gram-negative enteric bacteria in the fish and water suggesting contaminated water as a source for the fish contamination.
.png){kind=logo}
Research Article
Mar 30, 2018
Diversity, Relative Abundance, Species Composition and Some Biological Aspects of Fishes in Gilgel ... Abay and Andassa Rivers, Blue Nile Basin, Ethiopia
Diversity, relative abundance and some biological aspect of fishes in Gilgel Abay and Andassa Rivers were studied from September 2010 to June 2011 by using gillnets of mesh sizes 6 cm, 8 cm, 10 cm and 12 cm, monofilaments of different mesh sizes, cast net, hook and lines. Fish species identification was done by using literature and specimen deposited in the laboratory. Abiotic parameters such as temperature, conductivity, pH, total dissolved solids and transparency of the rivers were also taken, using multi-meters. The analysis of independent ttest showed that there was significant deference in pH and transparency between seasons in Andassa River (p<0.05). In Gilgel Abay River, there was significant difference in temperature and transparency (p<0.05) between seasons. Totally 939 fish specimens were collected from Gilgel Abay and Andassa Rivers. Three families and thirteen species of fishes were identified from Andassa and Gilgel Abay Rivers. Labeobarbus intermedius, Varicorhinus beso, L. nedgia and Clarias gariepinus were the most dominant fish species found in both Rivers. Index of Relative Importance (IRI) and Shannon Diversity Index (H') were used to evaluate the abundance and diversity of fish species. Andassa River had higher diversity (H'=4.06) than Gilgel Abay River (H'=4.05) in dry season but lower than Gilgel Abay in wet season which was (H'=3.32) and 4.35, respectively. In wet season, the most abundant species in Andassa River were L. intermedius, V. beso, C. gariepinus and L. crassibarbis. L. intermedius, L. nedgia and C. gariepinus were the most abundance species in Gilgel Abay during wet season. In both seasons, L. intermedius was the most important species at Andassa and Gilgel Abay Rivers. In Gilgel Abay River, the most important fish species in wet and dry seasons were L. intermedius, L. nedgia and C. gariepinus. The sex ratio analysis showed that there was significant deviation from unity (p<0.05).
.png){kind=logo}
Research Article
Mar 29, 2018
Acute Toxicity of Zinc Sulfate Heptahydrate (ZnSO4*7H2O) and Copper (II) Sulfate Pentahydrate (CuSO ... 4*5H2O) on Freshwater Fish, Percocypris pingi
This study was carried out to determine acute toxicity of two heavy metals (zinc and copper) to fingerlings Percocypris pingi by static bioassays. The experimental fish were subjected to a range of concentrations of heavy metals. At different exposure periods (24 h, 48 h, 72 h and 96 h), the mortality rate were separately investigated. The median lethal concentration (LC50) was determined with Probit analysis. The LC50 values of zinc for the Percocypris pingi at 24 h, 48 h, 72 h and 96 h were 3.504 mg/L, 2.933 mg/L, 2.852 mg/L and 2.852 mg/L, respectively. But the LC50 values of copper at 24 h, 48 h, 72 h and 96 h were 1.730 mg/L, 1.389 mg/L, 1.340 mg/L and 1.340 mg/L, respectively. The heavy metals were ranked in order of toxicity: copper >zinc. The safe concentration of zinc and copper were 0.2852 mg/L and 0.1340 mg/L, respectively. Physicochemical parameters variables e.g. dissolve oxygen, total hardness, and ammonia nitrogen of aquaria were monitored under different concentrations of zinc (0, 1.60, 2.40, 3.20, 4.00, 4.80, 5.60) mg/L and copper (0, 0.60, 1.00, 1.40, 1.80, 2.20, 2.60) mg/L.
.png){kind=logo}
Research Article
Mar 06, 2018
Freshwater Fisheries Resource Potential Estimation: The case of Lake Ardibo, Northern Ethiopia
The study investigates aspects of the fresh water fish resource potential estimation by considering Lake Ardibo, a Crater Lake in the northern highland of Ethiopia. The general aim of this study was to produce a scientific guidance paper on the estimation of fish resource potential of Lake Ardibo and to show the practical applicability of the different fish resource potential estimations models in Lake Ardibo. And this research was done by taking seasonal data from the selected three sampling sites i.e. some limnological parameters (physico-chemical parameters) in the period from February 2009 till January 2010. The sampling sites were located the first one near the shore (littoral site-SS1), the other the vegetated-SS2, one with a relatively dense macrophyte vegetation and the 3rd site was pelagic-SS3. The locations of the sites were identified by the Global Positioning System (GPS). And also series year of catch effort data were collected from Woreda livestock and fishery office and fishery cooperatives. Based on the collected data analysis were made using empirical and Schaefer production models. Hence the empirical models estimation shows 98.1 kg per hectare per year or 206 tons per year; whereas the Schaefer production model gives maximum sustainable yield (MSY) of 3452.5 kg per hectare per year or 3.45 tons per hectare which means 7250 tons per year from the lake and fMSY is 416 standard boats. Results of the Schaefer-Fox model were higher than the empirical estimates. Thus, the Lake can provide sustainable a production of fish, i.e., MSY on average 98.1 kg/ha per year or 206 tons per year from empirically found relationships.
.png){kind=logo}
Research Article
Feb 16, 2018
Preliminary Survey of Gram-Negative Bacterial Pathogens from Commonly Caught Fish Species (Oreochro ... mis niloticus, Cyprinus carpio and Clarias gariepinus) in Lake Hayiq, Ethiopia
A cross-sectional study was conducted from October 2016 to May 2017 on Oreochromis niloticus, Cyprinus carpio and Clarias gariepinus fish species at Lake Hayiq, North East Ethiopia with the objective of isolation and identification of major gram-negative bacterial pathogens of commonly catched fish species from Lake Hayik. A total of 98 live fishes (49 Oreochromis niloticus, 30 Cyprinus carpio and 19 Clarias gariepinus) were collected and transported to the laboratory. From the three fish species a total of 384 organ samples (96 skins, 98 gills, 94 intestines, 33 swim bladders, 19 kidneys, and 44 livers) were taken. A systematic random sampling technique was used to select the fish samples after drawn from the water. Among 384 fish organ samples 116 (30.2%) gram negative bacterial isolates were found: 9 (2.3%) Aeromonas species, 24 (6.3%) Pseudomonas species, 6 (1.6%) Enterobacter species, 29 (7.6%) Escherichia species, 4 (1.6%) Edwardsiella species, 11 (2.9%) Klebsiella species, 5 (1.3%) Proteus species, 8 (2.1%) Vibrio species, 14 (3.6%) Flavobacter species and 6 (1.6%) Salmonella species were found. Isolation among organs: Pseudomonas species, skin (33.3%), intestine (33.3%), and swim bladder (12.5%); Escherichia species: intestine (41.4%), skin (24.2%) and gill (24.2%) and Klebsiella species: liver (27.3%), gills (36.4%) were found. All the isolated bacterial species were gram-negative bacteria. From the three fish species, Oreochromis niloticus was the most affected fish species (48.2%) while Clarias gariepinus species were the least affected species (17.2%). In conclusion, majorities of those pathogens isolated and identified were very important for different fish disease outbreaks and also public health importance. But, very few and disintegrated studies with scanty data have been done whereas, it has been nowadays fishery is one of the main growth transformation plan for food security in Ethiopia. Therefore, it needs further integrated investigation on fish bacterial diseases.
.png){kind=logo}
Research Article
Jan 11, 2018
African Catfish Aquaculture in Malaysia and Nigeria: Status, Trends and Prospects
Global aquaculture production continue growing in order to meet up with ever increasing fish demand, especially as fish from capture has levelled off and makes an increase in aquaculture production as the only hope to meet the demand for fish. Aquaculture industry involves culture of many fish species of either fresh or brackish water origin and among the important freshwater fish species is North African catfish which is also called African catfish (Clarias gariepinus). Its production is increasing as the total aquaculture production also increases and its culture is spread globally, with Nigeria officially reported as producing the highest annual amount of the fish. There is a substantial culture of the fish in Malaysia, though not a native fish species but its presence in Malaysia is getting closer to over three decades and for almost a decade now, it has been the highest finfish produced in either fresh or brackish water aquaculture in Malaysia. This review discussed African catfish aquaculture in Malaysia and Nigeria, compared the production and prospects of the industry in the two countries.
.png){kind=logo}
Research Article
Dec 29, 2017
Comparative Growth Performance and Proximate Nutrient Composition of Three Local Strains of Nile Ti ... lapia (Oreochromis Niloticus L.) Collected From Different Locations in Uganda
The availability of O. niloticus fingerlings remains a problem in South Western Highland Agro-Ecological Zones. Most fish farmers produce only small sized fish probably because of inbreeding in Uganda. Brood stocks of Nile tilapia, Oreochromis niloticus L. were collected from Lakes Victoria, Kyoga and Kayumbu, a minor lake in SWHAEZ. The brood-stock were conditioned and bred. Fingerlings of F1 generation of each strain were fed diet containing 35% Crude Protein for 90 days. The results showed that Victoria strain growth performance was better compared to other tilapia strains in growth performance. Survival rate was not significantly different among Nile tilapia strains. Crude protein contents in fish body was higher in Victoria (69.30%) followed by Kayumbu strains (68.125%) with Kyoga having the least crude protein content (64.5%). Fish body of Kayumbu strains contained higher values of crude fat (11.70%) followed by Victoria strain (9.90%) while Kyoga strain had the least crude lipid (8.50%). The Victoria strain (47.8 g feed/fish) had significantly higher feed intake and PER than all the other strains. Kyoga and Kayumbu strains were comparable in terms of feed intake. However, the Kayumbu strain had significantly the least PER (2.46). The lowest FCR value was obtained in Kayumbu strain (1.67), while the higher ones were obtained in Kyoga and Victoria strains 1.82 and 1.78, respectively). The poor performance of kayumbu strain was probably due to in breeding and other environmental factors like temperatures. Therefore, exploitation of the genetic variation within the different native wild strains through selective breeding can help to improve growth performance of the Kayumbu strain in South Western Highland Agro-Ecological Zones (SWHAEZ).
.png){kind=logo}
Research Article
Dec 13, 2017
Description of Myxidium tetraodoni Sp. Nov., Myxidium anisocapsularis Sp. Nov. and Myxobolus magai ... Sp. Nov. (Myxosporea: Bivalvulida) Infecting Some Freshwater Fishes in Cameroon (Central Africa)
Examination of some Teleost fishes captured in the Maga detention lake located in the Far North Region of Cameroon, revealed the presence of three new species of Myxosporidia of the genera Myxidium Bütschli, 1882 and Myxobolus Bütschli, 1882 of which complete description is given in the present study. These species are: Myxidium tetraodoni sp. nov., parasite of the urinary bladder of Tetraodon lineatus Linnaeus, 1758 (Tetraodontidae) that form ellipsoidal spores with a turgid middle part and rounded ends. They measured 11.6 (10.5-12.5) µm long × 8.2 (7.2-9.6) µm broad; the spherical polar capsules are of equal size and measure 3.7 (3.0-4.3) µm. Myxidium anisocapsularis sp. nov., a parasite of the gall bladder of Distichodus engycephalus Günther, 1964 (Distichodontidae) form spindle-shaped and elongated spores, that measure 15.2 (14.0-16.2) µm long × 6.0 (5.0-6.7) µm broad; its polar capsules are quite unequal and respectively measure 6.0 (5.0-6.5) × 3.3 (3.0-3.8) µm for the larger and 4.7 (4.0-5.5) × 3.0 (2.3-3.3) µm for the smaller. Myxobolus magai sp. nov., a gill parasite of Labeo batesii Boulenger, 1911 (Cyprinidae) form ovoid spores with the anterior end larger with small protuberance, that measure 10.6 (9.0-12.0) × 6.3 (5.5-7.0) µm. Its polar capsules measure 2.8 (2.4-3.4) × 2.3 (2.0-3.0) µm.
.png){kind=logo}
Research Article
Nov 21, 2017
Population Dynamics of Bigeye Grunt, Brachydeuterus auritus (Valenciennes, 1831) in Ghana and Manag ... ement Implications
Population dynamics of Brachydeuterus auritus harvested from Ghana’s coastal waters was assessed following previous indications that this important species is collapsing. In view of this, a total of 849 samples of B. auritus were collected from February 2016 to January 2017, measured for total lengths and examined using FiSAT II. The mean length was 13.7 cm with a growth pattern of 2.8. The asymptotic length (L∞) and growth rate (K) were 21.53 cm and 0.67 yr-1 respectively portraying that this species is a fast-growing species. The lengths at first maturity and capture were calculated as 14.4 cm and 6.02 cm respectively which indicated the presence of growth overfishing. The critical length at capture (Lc=0.28) was lower than 0.5, supporting the earlier assertion that the investigated fish species is plagued with growth overfishing. Natural mortality rate (M=1.44/yr) was higher than fishing mortality rate (F=1.22/yr) an indication that small sized fished fishes were largely harvested. The recruitment layout was unremitting throughout the year with two major peaks showing the presence of strong recruitment into the stock - a strategy to avert extinction of its species. However, the exploitation rate (E=0.46) was slightly lower than the Emax (0.52) showing that the biomass of the investigated stock could surpass the maximum sustainable yield (Emax) if necessary fishery management options are not put in place. Furthermore, using the Quadrant rule, the investigated stock was categorized as developing, hence any unsustainable increase in fishing efforts could facilitate growth overfishing leading to its collapse. Therefore, to ensure sustainable exploitation and contribution to protein requirement for coastal community households, relevant fisheries measures are advocated
.png){kind=logo}
Research Article
Oct 27, 2017
Fecundity and Condition Factor of Clarias anguillaris of Oguta Lake, Nigeria
Fecundity and condition factor of Clarias angullaris were studied in Oguta Lake for eight weeks. Forty species of C. anguillaris were studied. The length-weight relationship, fecundity, condition factor and gonad-osomatic indices were factors employed for assessment of health status of the fish. The mean length and weight of the C. anguillaris collected were 27.46 ± 1.47 (12.00-38.50) cm and 391.26 ± 17.92 (144.60-553.40) g respectively. Some of the morphometrics manifested linkage and C. anguillaris exhibited a coefficient of determination (R2) of 0.008, and Pearson’s correlation coefficient (r) of -0.091. Fecundity-weight relationship of C. anguillaris was also not significant (p=0.062) with a Pearson’s correlation coefficient (r) of -0.357 and coefficient of determination (R2 )=0.127. The variations in condition factor of C. anguliaris at Oguta Lake was 19.96% (R2=0.1996) and this was explained by the variations in GSI. Clarias anguillaris from the Oguta Lake showed negative allometric growth pattern which implied that the fish species is increasing in length faster than its weight. This could be as a result of the polluted nature of the Lake, shortage of food supply, diseases which might have altered the fish speciation
.png){kind=logo}
Research Article
Oct 13, 2017
Length-Weight Relationship, Condition Factor and Gut Content of Chrysichthys Furcatus Gunther, 1864 ... (Bagridae) from Cross River at Ahaha
The study aimed to estimate the length weight relationship, condition factor and gut content of Chrysichthys furcatus a commercial important food fish in Obubra, central Cross River State. Monthly samples were collected for six month between May to October 2014. During the period a total of 187 specimens comprising of 125 females and 62 males were collected. The length - weight frequency distribution shows a total length ranged of 16 cm-60 cm and weight 50 g-549 g. The female fish have the highest length and weight frequency distribution except at weight ranged of 50 g-99 g where the males were more. Both sexes exhibited negative allometric growth pattern with an increased in length resulting to increase in weight of the fish. The condition factor (k) decreased with increased in the size of fish, why July and August recorded the least monthly condition factor. About 102 (54.55%) stomachs had some degree of food items in their guts with medium size specimens having the highest number of stomachs with some degree of food than small and large respectively. A total of 7 major categories with 27 food items comprising of animals, plants and detritus materials were identified. The sum total of 3,486 prey item with Cyclops (531) 15.24% constituting the most encountered while coleopteran (10) 0.29% was the least encountered prey. The most occurred prey item was detritus (100%) and Cyclops (98.12%) while the least coleopterans 3.67% with sand grains (11.44%) constituting the bulks of the gut content. The index of relative importance (IRI) reveals that Cyclops (1736.72), keretela (1394.82), tublex (1251.06), crustacean (1238.33) and crustacean eggs (1238.33) were the important and preferred prey item in the guts of C. furcatus. The ability of fish to capitalize on any available food items in the environment (euryphagous) is an important characteristic of culturable fish species. This implies that C. furcatus have brighter prospects for culture in ponds and proper species management and sustainability.
.png){kind=logo}
Research Article
Sep 29, 2017
Comparative Studies of Several Physiologic and Biochemical Indexes of Wild Type and Hatchery-Bred S ... turgeons in the Early Ontogenesis
It was shown that, depending on the ways of breeding and living conditions, realization of food-seeking and defensive behavioural reactions as well as single biochemical indexes (pattern of neurotransmitters and levels of free amino acids in the brain) in the wild type and hatchery-bred sturgeon juveniles differ significantly. Basing on the studied indexes, the juveniles, bred in the ponds, are close to the wild type juveniles, whereas the juveniles, bred by pool technique, are quite different from them.
.png){kind=logo}
Research Article
Sep 29, 2017
Growth and Energy Metabolism of Tambaqui (Colossoma Macropomum) Fed Diets with Different Levels of ... Carbohydrates and Lipids
The study assessed the protein sparing effect resulting from carbohydrate (CHO) and lipid (LIP) use and metabolic responses of juvenile tambaqui fed diets with different proportions of CHO and LIP. In a completely randomized 3 × 2 factorial design, the 6 diets tested combined 3 CHO (410 gkg-1, 460 gkg-1 and 510 gkg-1) and 2 LIP (40 gkg-1 and 80 gkg-1) levels. The 1080 fish tested (10.88 g ± 0.13 g mean body weight) were randomly distributed into twenty-four 500-L tanks (45 fish per tank). An increase in diet CHO and LIP levels improved feed conversion and protein efficiency ratio. The highest addition of CHO (510 gkg-1) and LIP (80 gkg-1) reduced diet intake and weight gain and increased serum triglyceride levels and fat deposition in muscle and liver. Glucose levels, serum protein and liver glycogen showed no difference between treatments with different CHO and LIP levels. Liver and muscle fat deposition were higher in the treatments with the highest diet LIP level, irrespective of diet CHO. The hepatosomatic index (HSI) and viscerosomatic fat index (VSI) exhibited no differences between treatments. Therefore, tambaqui can use both CHO and LIP to optimize protein use. The physiological responses indicate that the best CHO-LIP combination in tambaqui diets is 460 gkg-1 and 40 gkg-1, respectively. This combination promotes satisfactory growth without causing excess fat accumulation.
.png){kind=logo}
Research Article
Sep 25, 2017
Age, growth and diet of Reba carp Cirrhinus reba (Hamilton 1822) in Lower Anicut reservoir, Tamil N ... adu, India
The Reba carp Cirrhinus reba (Hamilton) has a best food category fish in India and its adjacent countries. The natural resources of this species are on the way out due to over exploitation and habitat changes. Here, is an important consideration that should be taken into account to the develop conservation strategies of the species. Besides, the present investigation was designed the health condition, age and growth and assessment of feeding behaviour. Following this, the species health status was assessed by Fulton’s condition factor and reported their irrelevant growth related to the size. C. reba attained the highest growth rate in females than males were strongminded by von Bertallanffy Growth Factor parameters and Electronic Length Frequency Analysis. However, analysis of stomach contents was revealed that this species were observed an omnivore, particularly plankton feeder. So far, the objective of this study was to provide necessary inputs on the biological parameters of this species for artificial propagation programs and conserved natural populations in our riverine ecosystem.
.png){kind=logo}
Research Article
Sep 21, 2017
Maturation and Reproductive Biology of Reba Carp Cirrhinus Reba (Hamilton) in Lower Anicut Reservoi ... r, Tamil Nadu, India
Examine the reproductive biology of Cirrhinus reba at Lower Anicut reservoir and analyses of gonads assessed by ovarian cycles. Sex ratio, size at first maturity, GSI, macroscopic appearance ovary, fecundity, oocyte diameter and histological examination suggested as a result of spawning season. Males were 59.4% and females 40.6% suggested the ratio significantly deviated from expected 1:1. Size at 50% maturity estimated from logistic model curve 132 mm in males and 148 mm for females. GSI was represented increasing the development of gonads in both sexes until it was ripe and spent. During spawning, increasing the length and weight of gonads from immature to ripe, maximum values of GSI for both sexes (3.43%-3.49% to 4.09%- 6.01%) were obtained during April to August with peak in July. Size-frequency distribution of ova diameter were clearly indicate maximum values of diameter enclosed during July to corresponding microscopic stages of gonads. Five stages of oocyte development were determined through histological examination can be divided immature, maturing, matured, ripe and spent. Total length, weight, gonad length and weight were significantly related to fecundity. Stocks of C. reba were enclosing females spawn once a year during spawning season. Following, the implications for management and controlled feral carp stocks were discussed in detail.
