This research investigated the growth performance of Clarias gariepinus fingerlings (mean weight 1.130.3g) fed cockroach meal (CM) as replacement for fish meal (FM). The fish were fed with three diets containing 45% crude protein; diet 1 (control 0% CM and 0% FM) diet 2 (10% FM, 0% CM), diet 3 (10% CM, 0% FM) for 56 days. The results showed significant differences (p<0.05) for the growth parameters evaluated for the treatments. Cockroach meal-based diet gave the best results in terms of mean weight gain (1.39+0.39g), food conversion ratio (2.54+0.15), specific growth rate (1.440.29%/day), protein efficiency ratio (0.87±0.20), apparent net protein utilization (16.23±7.19) and survival rate of 62%. This was followed by fish meal-based diet while the control diet gave a significantly (p<0.05) lower values. It can be concluded from the study that cockroach meal can substitute fish meal at 10% inclusion level. However, further study can be conducted for higher inclusion levels of cockroach meal in the diets of C. gariepinus. Keywords: Insect meal, protein, catfish, feed, growth.
{"title":"Effects of replacing fish meal with cockroach (Periplaneta americana) meal in the diet of African catfish (Clarias gariepinus) fingerlings","authors":"A. Orire, G. B. Fasomo, M. A. Haruna","doi":"10.4314/jas.v34i2.16","DOIUrl":"https://doi.org/10.4314/jas.v34i2.16","url":null,"abstract":"This research investigated the growth performance of Clarias gariepinus fingerlings (mean weight 1.130.3g) fed cockroach meal (CM) as replacement for fish meal (FM). The fish were fed with three diets containing 45% crude protein; diet 1 (control 0% CM and 0% FM) diet 2 (10% FM, 0% CM), diet 3 (10% CM, 0% FM) for 56 days. The results showed significant differences (p<0.05) for the growth parameters evaluated for the treatments. Cockroach meal-based diet gave the best results in terms of mean weight gain (1.39+0.39g), food conversion ratio (2.54+0.15), specific growth rate (1.440.29%/day), protein efficiency ratio (0.87±0.20), apparent net protein utilization (16.23±7.19) and survival rate of 62%. This was followed by fish meal-based diet while the control diet gave a significantly (p<0.05) lower values. It can be concluded from the study that cockroach meal can substitute fish meal at 10% inclusion level. However, further study can be conducted for higher inclusion levels of cockroach meal in the diets of C. gariepinus. \u0000Keywords: Insect meal, protein, catfish, feed, growth.","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"79 1","pages":"133-142"},"PeriodicalIF":0.0,"publicationDate":"2020-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90786683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Feeding trial was carried out to evaluate sperm quality of Clarias anguillaris broodstock fed varying inclusion levels of goron tula, Azanza garckeana pulp meal. The fish (mean weight 500g) were randomly distributed in concrete tanks (2 x 2 x 1.2m) at nine fish/tank in triplicates. Five isonitrogenous diets (40% CP) were formulated with the pulp meal incorporated at the rate of 0, 5, 10, 15, and 20% of the diet. Fish were fed at 3% of body weight for 56days. At the end of the feeding trial, results showed that dietary A. garckeana significantly (p<0.05) improved the milt quality of C. anguillaris. The broodfish fed 20% A. garckeana inclusion level had the highest (p<0.05) milt volume, sperm motility duration, testes lobe lengths, and whole sperm count while the least values of these variables were observed in group fed with the control diet (0% inclusion level). The findings conclusively revealed that increase in the level of A. garckeana pulp meal in the diet resulted into increase in sperm quality of C. anguillaris. Thus, the pulp meal can be freely utilized in catfish production in terms of sperm quality for mass fingerling production. Keywords: A. garckeana, Clarias anguillaris, sperm count, motility duration, milt volume.
本试验通过饲喂不同添加水平的黄颡鱼、黄颡鱼浆粕，对鳗鲡的精子质量进行了评价。鱼(平均体重500g)随机分布在2 x 2 x 1.2m的混凝土罐中，每箱9条鱼，一组3次。配制5种等氮饲粮(40% CP)，分别以饲粮中0%、5%、10%、15%和20%的比例添加纸浆粕。按体重的3%饲喂56d。试验结束时，结果表明:饲粮中添加加棘豆显著(p<0.05)提高了鳗鲡的面粉品质。20%添加水平的黄颡鱼乳体积、精子活动时间、睾丸叶长和全精子数最高(p<0.05)，而对照组(0%添加水平)最低。研究结果表明，日粮中猕猴桃浆粕含量的增加导致鳗鲡精子质量的提高。因此，就大量鱼种生产的精子质量而言，可以在鲶鱼生产中自由利用浆粕。关键词:沙蚕，鳗鲡，精子数，活动时间，精子体积
{"title":"Evaluation of milt quality of Clarias anguillaris (Linnaeus, 1758) Broodstock fed varying inclusion levels of wild hibiscus Azanza garckeana pulp meal","authors":"I. J. Ochokwu, M. .. Nwabunike, G. Udeh","doi":"10.4314/jas.v34i1.4","DOIUrl":"https://doi.org/10.4314/jas.v34i1.4","url":null,"abstract":"Feeding trial was carried out to evaluate sperm quality of Clarias anguillaris broodstock fed varying inclusion levels of goron tula, Azanza garckeana pulp meal. The fish (mean weight 500g) were randomly distributed in concrete tanks (2 x 2 x 1.2m) at nine fish/tank in triplicates. Five isonitrogenous diets (40% CP) were formulated with the pulp meal incorporated at the rate of 0, 5, 10, 15, and 20% of the diet. Fish were fed at 3% of body weight for 56days. At the end of the feeding trial, results showed that dietary A. garckeana significantly (p<0.05) improved the milt quality of C. anguillaris. The broodfish fed 20% A. garckeana inclusion level had the highest (p<0.05) milt volume, sperm motility duration, testes lobe lengths, and whole sperm count while the least values of these variables were observed in group fed with the control diet (0% inclusion level). The findings conclusively revealed that increase in the level of A. garckeana pulp meal in the diet resulted into increase in sperm quality of C. anguillaris. Thus, the pulp meal can be freely utilized in catfish production in terms of sperm quality for mass fingerling production. \u0000Keywords: A. garckeana, Clarias anguillaris, sperm count, motility duration, milt volume.","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"31 1","pages":"23-31"},"PeriodicalIF":0.0,"publicationDate":"2020-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77398363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The importance of inland fisheries sector cannot be over-emphasized and its significance in providing food security and generating local income is not in doubt. Production from inland open water capture fisheries is declining due to over-exploitation and habitat degradation. The rapidly declining catch from fish landing is a possible indication that the fish yields of most Nigerian inland waters are generally low for causes that may range from inadequate management of fisheries to degradation of water bodies. Artisanal fishing in the Niger Delta is faced with myriads of obstacles emanating from human activities; one of these problems being the menace of the commercial fishing trawlers and activities of the oil companies in the area. The local supply of fish and fishery products consists of production from the artisanal (85%), industrial (14%) and Aquaculture (1%) subsectors. The high activity level in the Niger Delta has exposed the area to the dangers of pollution of water, land and air as well as oil spills which have endangered aquatic life as well as the entire ecosystem, topography and surface vegetation leading to loss of biodiversity and conflicts. The contribution of fisheries to the nation economy is very significant in terms of employment, income generation, poverty alleviation, foreign exchange earnings and provision of raw materials for the animal feed industry. In order for biodiversity conservation to be effective, management measures must be broad based. Keywords: Inland Fisheries, Aquaculture, Over-exploitation, Sustainable, and Pollution.
{"title":"Inland fisheries: Status, management and related conflicts in the niger delta, Nigeria","authors":"S. U. Nwaka, I. Isangedighi, N. L. Isemin","doi":"10.4314/jas.v34i1.8","DOIUrl":"https://doi.org/10.4314/jas.v34i1.8","url":null,"abstract":"The importance of inland fisheries sector cannot be over-emphasized and its significance in providing food security and generating local income is not in doubt. Production from inland open water capture fisheries is declining due to over-exploitation and habitat degradation. The rapidly declining catch from fish landing is a possible indication that the fish yields of most Nigerian inland waters are generally low for causes that may range from inadequate management of fisheries to degradation of water bodies. Artisanal fishing in the Niger Delta is faced with myriads of obstacles emanating from human activities; one of these problems being the menace of the commercial fishing trawlers and activities of the oil companies in the area. The local supply of fish and fishery products consists of production from the artisanal (85%), industrial (14%) and Aquaculture (1%) subsectors. The high activity level in the Niger Delta has exposed the area to the dangers of pollution of water, land and air as well as oil spills which have endangered aquatic life as well as the entire ecosystem, topography and surface vegetation leading to loss of biodiversity and conflicts. The contribution of fisheries to the nation economy is very significant in terms of employment, income generation, poverty alleviation, foreign exchange earnings and provision of raw materials for the animal feed industry. In order for biodiversity conservation to be effective, management measures must be broad based. \u0000Keywords: Inland Fisheries, Aquaculture, Over-exploitation, Sustainable, and Pollution.","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"112 1","pages":"57-70"},"PeriodicalIF":0.0,"publicationDate":"2020-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79708348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
There had been growing interest in the use of extracts from different plants species to boost fish production. In this study Gongronema latifolium leaf extract was supplemented in a commercial diet of Clarias gariepinus juveniles at varying concentrations of 0.5g (T2), 1.0g (T3) and 1.5g (T4) per kg of feed while the control (T1) had no leaf extract. They were fed for 8weeks while growth performance and haematological data were collected and analysed. Proximate composition of the fish flesh was carried out after the feeding trials. The initial mean weight ranged between 9.0±0.5 to 9.0±0.7g, the best mean weight gain (14.3±2.0g) was observed in T3 while the least (12.3±6.2) in T2. Specific growth rate recorded was 5.4±0.4, 5.3±0.5, 5.4±0.1 and 5.3±0.2 for T1, T2, T3 and T4 respectively. There was no significant difference (p>0.05) in the survival rates among treatments. The best feed conversion ratio was observed in T3 and the control group. The results of haematological indices revealed that red blood count ranged between 3.0±0.1109cells/l in T3 to 33.61±0.2 109cells/l in T1, pack cell volume (38.9±1.3%) was best in T1, the least white blood cell (165.1±4.9109cells/l) in T4 while the highest level (169.8±1.3109cells/l) was recorded in (T1). The platelets and mean corpuscular haemoglobin concentration showed no significant difference amongst the treatments. The haematological results showed that the leaf extract enhanced the status of some of the haematological parameters such as the white blood cell. The proximate composition of the fish flesh was not significantly different amongst the treatments. The findings of this study also revealed that increase in the concentration of the leaf extract affected the acceptability of the feed hence a decline in growth. Considering the foregoing, G. latifolium leaf extract has shown to have some prospects in aquaculture when supplemented at various concentrations. Keywords: Gongronema latifolium, Clarias gariepinus, haematology, leaf extract, juveniles
{"title":"Growth performances, nutrient utilization and haematology of Clarias gariepinus juveniles fed varying concentrations of Gongronema latifolium leaf extracts","authors":"J. Ikwuemesi, O. Irozuru, I. Okwu","doi":"10.4314/jas.v34i2.12","DOIUrl":"https://doi.org/10.4314/jas.v34i2.12","url":null,"abstract":"There had been growing interest in the use of extracts from different plants species to boost fish production. In this study Gongronema latifolium leaf extract was supplemented in a commercial diet of Clarias gariepinus juveniles at varying concentrations of 0.5g (T2), 1.0g (T3) and 1.5g (T4) per kg of feed while the control (T1) had no leaf extract. They were fed for 8weeks while growth performance and haematological data were collected and analysed. Proximate composition of the fish flesh was carried out after the feeding trials. The initial mean weight ranged between 9.0±0.5 to 9.0±0.7g, the best mean weight gain (14.3±2.0g) was observed in T3 while the least (12.3±6.2) in T2. Specific growth rate recorded was 5.4±0.4, 5.3±0.5, 5.4±0.1 and 5.3±0.2 for T1, T2, T3 and T4 respectively. There was no significant difference (p>0.05) in the survival rates among treatments. The best feed conversion ratio was observed in T3 and the control group. The results of haematological indices revealed that red blood count ranged between 3.0±0.1109cells/l in T3 to 33.61±0.2 109cells/l in T1, pack cell volume (38.9±1.3%) was best in T1, the least white blood cell (165.1±4.9109cells/l) in T4 while the highest level (169.8±1.3109cells/l) was recorded in (T1). The platelets and mean corpuscular haemoglobin concentration showed no significant difference amongst the treatments. The haematological results showed that the leaf extract enhanced the status of some of the haematological parameters such as the white blood cell. The proximate composition of the fish flesh was not significantly different amongst the treatments. The findings of this study also revealed that increase in the concentration of the leaf extract affected the acceptability of the feed hence a decline in growth. Considering the foregoing, G. latifolium leaf extract has shown to have some prospects in aquaculture when supplemented at various concentrations. \u0000Keywords: Gongronema latifolium, Clarias gariepinus, haematology, leaf extract, juveniles","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"56 1","pages":"97-105"},"PeriodicalIF":0.0,"publicationDate":"2020-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77427091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bioaccumulation of heavy metals (cadmium, Cd; chromium,Cr; lead, Pb; copper, Cu) in plankton and water from Elechi creek were studied for twelve months. Plankton and water samples collected using plankton net and bottles were analysed for heavy metals following standard method of APHA and the data obtained were subjected to statistical analysis. Results showed that plankton accumulated more heavy metals than water with the orders of magnitude, Cu> Cd > Cr >Pb and Cu > Cr> Pb> Cd for plankton and water respectively. The mean values of heavy metals in water were lower than the EPA, USEPA and WHO permissible limits for human consumption. Pb concentration in plankton differed significantly in station 4 while Cu differed seasonally with dry season values higher than wet season values unlike the heavy metal concentration in water. The higher bioconcentration factor (BCF) and the order, Cd>Pb>Cr> Cu observed showed that plankton has high potential to concentrate heavy metals. The dominance by Bacillariophyceae followed by Chlorophyceae and Cyanophyceae in species and abundance and the presence of indicator species, Cyclotella species , Melosira monoliformis and Navicula distans indicates pollution. This calls for awareness and constant assessment to avoid further contamination of the resources meant for human consumption. Keywords: Heavy metals, plankton, bioaccumulation, pollution, Elechi Creek
{"title":"Comparative evaluation of bioaccumulation of heavy metals in plankton and water from Elechi Creek, Port Harcourt, Nigeria","authors":"B. B. Otene, I. Ukwe","doi":"10.4314/JAS.V32I2.12","DOIUrl":"https://doi.org/10.4314/JAS.V32I2.12","url":null,"abstract":"Bioaccumulation of heavy metals (cadmium, Cd; chromium,Cr; lead, Pb; copper, Cu) in plankton and water from Elechi creek were studied for twelve months. Plankton and water samples collected using plankton net and bottles were analysed for heavy metals following standard method of APHA and the data obtained were subjected to statistical analysis. Results showed that plankton accumulated more heavy metals than water with the orders of magnitude, Cu> Cd > Cr >Pb and Cu > Cr> Pb> Cd for plankton and water respectively. The mean values of heavy metals in water were lower than the EPA, USEPA and WHO permissible limits for human consumption. Pb concentration in plankton differed significantly in station 4 while Cu differed seasonally with dry season values higher than wet season values unlike the heavy metal concentration in water. The higher bioconcentration factor (BCF) and the order, Cd>Pb>Cr> Cu observed showed that plankton has high potential to concentrate heavy metals. The dominance by Bacillariophyceae followed by Chlorophyceae and Cyanophyceae in species and abundance and the presence of indicator species, Cyclotella species , Melosira monoliformis and Navicula distans indicates pollution. This calls for awareness and constant assessment to avoid further contamination of the resources meant for human consumption. Keywords: Heavy metals, plankton, bioaccumulation, pollution, Elechi Creek","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87192285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study on length-weight relationship and condition factor of Bagrus bayad macropterus from Agbura River, a tributary of the Nun River was conducted monthly for eighteen months (April 2012 – December 2013). Three thousand, six hundred and forty (3640) fish samples comprising of one hundred and ninety-three (193) Bagrus bayad macropterus were collected using traditional fishing gear and drag nets. The specimens were preserved in ice-packed box and taken to laboratory for length-weight measurement. The length-weight relationship was estimated using the linear regression model 𝑊=𝑎𝐿𝑏 and condition factor (k) determined using the equation 𝐾=100𝑊𝐿𝑏 .The standard length ranged between 17.6 and 27.2 cm and the weight ranged between 170.56 and 501.30 g in males and 16.8 to 32.2 cm and 190.60 to 510.35 g in females. The value of length exponent was more than 3 showing positive allometric growth pattern. The b-values tested using ANOVA indicated a highly significant regression of weight on standard length (P<0.05). The correlation (r) between increase in length and gain in weight was significant. The condition factor ranged between 1.51 and 3.13 with mean k-value of 2.23. The k-values showed monthly variations with peak values between the months of January and April. The fish species was in good condition in the study area as the K values were above one throughout the period of study.Keywords: Condition factor, length- weight relationship, Bagrus bayad macropterus, Agbura River Niger Delta
{"title":"Condition factor and length-weight relationship of Bagrus bayad macropterus (Daget, 1954) from Agbura River, Niger Delta, Nigeria","authors":"P. E. Omoruwou, J. Meye","doi":"10.4314/JAS.V32I2.3","DOIUrl":"https://doi.org/10.4314/JAS.V32I2.3","url":null,"abstract":"The study on length-weight relationship and condition factor of Bagrus bayad macropterus from Agbura River, a tributary of the Nun River was conducted monthly for eighteen months (April 2012 – December 2013). Three thousand, six hundred and forty (3640) fish samples comprising of one hundred and ninety-three (193) Bagrus bayad macropterus were collected using traditional fishing gear and drag nets. The specimens were preserved in ice-packed box and taken to laboratory for length-weight measurement. The length-weight relationship was estimated using the linear regression model 𝑊=𝑎𝐿𝑏 and condition factor (k) determined using the equation 𝐾=100𝑊𝐿𝑏 .The standard length ranged between 17.6 and 27.2 cm and the weight ranged between 170.56 and 501.30 g in males and 16.8 to 32.2 cm and 190.60 to 510.35 g in females. The value of length exponent was more than 3 showing positive allometric growth pattern. The b-values tested using ANOVA indicated a highly significant regression of weight on standard length (P<0.05). The correlation (r) between increase in length and gain in weight was significant. The condition factor ranged between 1.51 and 3.13 with mean k-value of 2.23. The k-values showed monthly variations with peak values between the months of January and April. The fish species was in good condition in the study area as the K values were above one throughout the period of study.Keywords: Condition factor, length- weight relationship, Bagrus bayad macropterus, Agbura River Niger Delta","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"109 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80698748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study determined mortality, recruitment and exploitation rate of a commercially important fish, Protopterus annectens from Orashi River and River Sombriero between October 2013 and September 2014. A total of 347 individuals of P. annectens were collected fortnightly by commissioned fishers using multiple gear. The total mortality was 3.225 yr -1 , natural mortality was 1.465 yr -1 , fishing mortality was 3.107 yr -1 and exploration rate was estimated as 0.355. The exploration rate (Emax) that gave maximum relative yield per recruit was 0.355. The exploitation rate at which marginal increase was E= 10% was 0.263. The exploitation rate E=50% which corresponded to 50% of the margin or unexploited stock was 0.229. The mean ratio of length at first capture (LC) and asymptotic length (L∞) was 0.050 while that of natural mortality (M) and growth rate (Kyr -1 ) was 2.5. The recruitment pattern showed all year round recruitment with peak and latent periods. The parameters obtained were L∞ = 82.95, K = 0.18yr -1 , T = 29.1 0 C, L mean = 29.5cm, Lmax = 74.97cm. The fish was available all year round. There is need to ensure sustainability of the species in rivers by checking activities of indigenous inhabitants whose commercial activities may destroy the favourable environment of the fish. Keywords: Mortality, exploitation rate, recruitment, Protopterus annectens
该研究确定了2013年10月至2014年9月期间，来自Orashi河和Sombriero河的一种重要商业鱼类——颈原terus annectens的死亡率、捕捞率和捕捞率。委托渔民采用多渔具每两周采集347尾。总死亡率为3.225 yr -1，自然死亡率为1.465 yr -1，捕捞死亡率为3.107 yr -1，勘探率为0.355。每井最大相对产量的勘探率(Emax)为0.355。边际增量为E= 10%时的采收率为0.263。开采率E=50%，对应50%的边际或未开采量为0.229。首次捕获长度(LC)与渐近长度(L∞)之比均值为0.050，自然死亡率(M)与生长率(Kyr -1)之比均值为2.5。招聘模式为全年招聘，有高峰期和潜伏期。L∞= 82.95,K = 0.18yr -1, T = 29.10 C, L mean = 29.5cm, Lmax = 74.97cm。鱼一年四季都能吃到。有必要通过检查土著居民的活动来确保河流中鱼类的可持续性，因为他们的商业活动可能破坏鱼类的有利环境。关键词:死亡率，开采率，招募，节肢原蚁
{"title":"Mortality, exploitation rate and recruitment pattern of African lungfish, Protopterns annectens (Owen, 1839) from Orashi and Sombreiro Rivers, Niger Delta, Nigeria","authors":"C. Onwuka","doi":"10.4314/jas.v32i2.11","DOIUrl":"https://doi.org/10.4314/jas.v32i2.11","url":null,"abstract":"The study determined mortality, recruitment and exploitation rate of a commercially important fish, Protopterus annectens from Orashi River and River Sombriero between October 2013 and September 2014. A total of 347 individuals of P. annectens were collected fortnightly by commissioned fishers using multiple gear. The total mortality was 3.225 yr -1 , natural mortality was 1.465 yr -1 , fishing mortality was 3.107 yr -1 and exploration rate was estimated as 0.355. The exploration rate (Emax) that gave maximum relative yield per recruit was 0.355. The exploitation rate at which marginal increase was E= 10% was 0.263. The exploitation rate E=50% which corresponded to 50% of the margin or unexploited stock was 0.229. The mean ratio of length at first capture (LC) and asymptotic length (L∞) was 0.050 while that of natural mortality (M) and growth rate (Kyr -1 ) was 2.5. The recruitment pattern showed all year round recruitment with peak and latent periods. The parameters obtained were L∞ = 82.95, K = 0.18yr -1 , T = 29.1 0 C, L mean = 29.5cm, Lmax = 74.97cm. The fish was available all year round. There is need to ensure sustainability of the species in rivers by checking activities of indigenous inhabitants whose commercial activities may destroy the favourable environment of the fish. Keywords: Mortality, exploitation rate, recruitment, Protopterus annectens","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78942121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study evaluated the haematological parameters of Heterobranchus longifilis fingerlings fed different dietary levels of Leucaena leucocephala leaf meal. Five hundred (500) H. longifilis fingerlings of mean weight 6.56g ± 0.47 were randomly distributed into treatment tanks and fed twice a day at 3% body weight for 36 weeks. Experimental diets were compounded with each diet containing 10% (SW10), 20% (SW20), 30% (SW30) and 40% (SW40) inclusion of L. leucocephala leaf meal whereas fishmeal based diet (SWC) and commercial diet (SWCF) served as control. The determination of haematological parameters followed standard procedures. Results obtained showed that SWC and SWCF were significantly high (P 0.05). The haematological result revealed that fish fed diet containing 20% L. leucocephala leaf meal inclusion level did not adversely affect the blood parameters of H. longifilis fingerlings. Key Words : Blood parameters, nutrition, leaf meal, plant protein, Leucaena leucocephala, Heterobranchus longifilis
{"title":"Haematology of Heterobranchus longifilis fingerlings fed different dietary levels of Leucaena leucocephala leaf meal","authors":"A. Agbo, J. Balogun, S. Oniye, J. Auta","doi":"10.4314/jas.v32i2.5","DOIUrl":"https://doi.org/10.4314/jas.v32i2.5","url":null,"abstract":"This study evaluated the haematological parameters of Heterobranchus longifilis fingerlings fed different dietary levels of Leucaena leucocephala leaf meal. Five hundred (500) H. longifilis fingerlings of mean weight 6.56g ± 0.47 were randomly distributed into treatment tanks and fed twice a day at 3% body weight for 36 weeks. Experimental diets were compounded with each diet containing 10% (SW10), 20% (SW20), 30% (SW30) and 40% (SW40) inclusion of L. leucocephala leaf meal whereas fishmeal based diet (SWC) and commercial diet (SWCF) served as control. The determination of haematological parameters followed standard procedures. Results obtained showed that SWC and SWCF were significantly high (P 0.05). The haematological result revealed that fish fed diet containing 20% L. leucocephala leaf meal inclusion level did not adversely affect the blood parameters of H. longifilis fingerlings. Key Words : Blood parameters, nutrition, leaf meal, plant protein, Leucaena leucocephala, Heterobranchus longifilis","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"11 1","pages":"257-265"},"PeriodicalIF":0.0,"publicationDate":"2018-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82605856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Variations of some electrolytes such as Sodium (Na + ), Potassium (K + ), Chloride (Cl-) and Calcium (Ca 2+ )in the plasma of Clarias gariepinus juveniles and adults reared in grow-out concrete tanks and earthen ponds in three Agricultural Zones of Lagos State were assessed to determine the levels of osmotic impairment in fish raised using two grow-out aquaculture facilities. A total of six farms and a control farm were selected for the study based on their culture systems and production capacities (earthen ponds and concrete tanks). Sixty-four blood samples were collected from juveniles and adults of catfish reared in these farms for six months. Blood samples were analyzed by standard laboratory methods using Randox diagnostic test kit. Results from the electrolytes analyses indicated that the values of Na + and K + ions significantly increased (P 0.05) in Cl - between the control and other farms. While significant reduction (P < 0.05) of Ca 2+ were recorded in other farms when compared to the control. These alterations were more noticeable in the fish reared in MOY and TEM fish farms than other farms. Keywords : Aquaculture, stress, electrolytes, culture systems, catfish
{"title":"Changes in electrolytes levels in the plasma of Clarias gariepinus juveniles and adults reared in two grow-out facilities","authors":"N. M. Achlike","doi":"10.4314/jas.v32i2.4","DOIUrl":"https://doi.org/10.4314/jas.v32i2.4","url":null,"abstract":"Variations of some electrolytes such as Sodium (Na + ), Potassium (K + ), Chloride (Cl-) and Calcium (Ca 2+ )in the plasma of Clarias gariepinus juveniles and adults reared in grow-out concrete tanks and earthen ponds in three Agricultural Zones of Lagos State were assessed to determine the levels of osmotic impairment in fish raised using two grow-out aquaculture facilities. A total of six farms and a control farm were selected for the study based on their culture systems and production capacities (earthen ponds and concrete tanks). Sixty-four blood samples were collected from juveniles and adults of catfish reared in these farms for six months. Blood samples were analyzed by standard laboratory methods using Randox diagnostic test kit. Results from the electrolytes analyses indicated that the values of Na + and K + ions significantly increased (P 0.05) in Cl - between the control and other farms. While significant reduction (P < 0.05) of Ca 2+ were recorded in other farms when compared to the control. These alterations were more noticeable in the fish reared in MOY and TEM fish farms than other farms. Keywords : Aquaculture, stress, electrolytes, culture systems, catfish","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"33 1","pages":"249-256"},"PeriodicalIF":0.0,"publicationDate":"2018-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81957028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Illegal and overfishing are major threat to fisheries resource sustainability in Nigeria. The study determined social characteristics of fishers, level of awareness of the law and level of enforcement of fisheries law. A simple random sampling technique using 320 questionnaires was adopted to select the sampled population from four artisanal riverine communities along New Calabar River and Bonny Estuaries in Rivers State namely Station 1 (Nembe waterside), Station 2 (Mgbuosimini), Station 3 (Isaka-Bundu) and Station 4 (Borokiri-Rex-Lawson waterside). Respondents were identified through household listing. The level of education of fishers indicated that most of the sampled fishers were educated. From the respondents, only 1.56% was aware of the law. There was very high level of non-compliance to the 76 mm mesh size requirement; Nembe waterside, had 83.00%, Mgbuosimini had 76.00%, Isaka-Bundu had 80.00% and Borikiri Rex-Lawson Waterside had 85.00% mesh sizes less than 76 mm requirement. This indicated a violation of the mesh size requirement due to ignorance on the part of fishers and open access to the marine resources. Fishers agreed that the law should be reviewed. Therefore, the study recommends that there should be programmes to increase awareness of review of the provisions and enforcement of the law. Key Words : Factors, influencing, Fisheries Law, compliance, landing sites
{"title":"Status of fisheries law compliance in some fish landing sites in two local government areas of Rivers state, Nigeria","authors":"Adi George, D. B. Edubamo","doi":"10.4314/JAS.V32I2.7","DOIUrl":"https://doi.org/10.4314/JAS.V32I2.7","url":null,"abstract":"Illegal and overfishing are major threat to fisheries resource sustainability in Nigeria. The study determined social characteristics of fishers, level of awareness of the law and level of enforcement of fisheries law. A simple random sampling technique using 320 questionnaires was adopted to select the sampled population from four artisanal riverine communities along New Calabar River and Bonny Estuaries in Rivers State namely Station 1 (Nembe waterside), Station 2 (Mgbuosimini), Station 3 (Isaka-Bundu) and Station 4 (Borokiri-Rex-Lawson waterside). Respondents were identified through household listing. The level of education of fishers indicated that most of the sampled fishers were educated. From the respondents, only 1.56% was aware of the law. There was very high level of non-compliance to the 76 mm mesh size requirement; Nembe waterside, had 83.00%, Mgbuosimini had 76.00%, Isaka-Bundu had 80.00% and Borikiri Rex-Lawson Waterside had 85.00% mesh sizes less than 76 mm requirement. This indicated a violation of the mesh size requirement due to ignorance on the part of fishers and open access to the marine resources. Fishers agreed that the law should be reviewed. Therefore, the study recommends that there should be programmes to increase awareness of review of the provisions and enforcement of the law. Key Words : Factors, influencing, Fisheries Law, compliance, landing sites","PeriodicalId":32064,"journal":{"name":"Turkish Journal of Aquatic Sciences","volume":"74 1","pages":"275-283"},"PeriodicalIF":0.0,"publicationDate":"2018-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83748000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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