The intensification of aquaculture has emerged as a viable alternative for increasing aquaculture production due to competition that arose from the use of natural resources,such as land and water,by other production a...The intensification of aquaculture has emerged as a viable alternative for increasing aquaculture production due to competition that arose from the use of natural resources,such as land and water,by other production and developmental sectors.However,intensification demands increased inputs,such as fish and feed per unit culture area and,therefore,increased waste generation from the aquaculture production systems.The impact of waste products from aquaculture has increased public concern and threatens the sustainability of aquaculture practices.The need for increasing the production of aquaculture products cannot be overemphasized and,therefore,there is a need to develop culture systems that will increase fish production with efficient waste management in order to limit environmental degradation resulting from aquaculture wastes and ensure its sustainability.This paper reviewed various aspects of waste production from aquaculture,their sources,components,and methods of management,in different culture systems,primarily discussing waste production from feed,chemicals,and pathogens.We aimed to establish the sources of wastes,their contents,and potential harms to both the fish culture and the environment.Suggestions for managing wastes in different culture systems were made to ensure an improved and sustainable aquaculture production.展开更多
The aquafeed industry continues to expand in response to the rapidly growing aquaculture sector.However,the identification of alternative protein sources in aquatic animal diets to replace conventional sources due to ...The aquafeed industry continues to expand in response to the rapidly growing aquaculture sector.However,the identification of alternative protein sources in aquatic animal diets to replace conventional sources due to cost and sustainability issues remains a major challenge.Recently,insects have shown tremendous results as potential replacers of fishmeal in aquafeed.The present study aimed to review the utilization of insects in aquafeeds and their effects on aquatic animals’growth and feed utilization,immune response and disease resistance,and fish flesh quality and safety.While many insect species have been investigated in aquaculture,the black soldier fly(Hermetia illucens),and the mealworm(Tenebrio molitor)are the most studied and most promising insects to replace fishmeal in aquafeed.Generally,insect rearing conditions and biomass processing methods may affect the product’s nutritional composition,digestibility,shelf life and required insect inclusion level by aquatic animals.Also,insect-recommended inclusion levels for aquatic animals vary depending on the insect species used,biomass processing method,and test organism.Overall,while an appropriate inclusion level of insects in aquafeed provides several nutritional and health benefits to aquatic animals,more studies are needed to establish optimum requirements levels for different aquaculture species at different stages of development and under different culture systems.展开更多
Copper （Cu） contamination in the environment has been increased during the years with agricultural and industrial activities. Biotechnological approaches are needed for bioremediation in these areas. The aims of thi...Copper （Cu） contamination in the environment has been increased during the years with agricultural and industrial activities. Biotechnological approaches are needed for bioremediation in these areas. The aims of this study were i） to evaluate the phytoreme- diation capacity of the high-yielding bioenergy plant castor bean （Ricinus communis L.） in vineyard soils （Inceptisol and Mollisol） contaminated with Cu and a Cu mining waste; ii） to characterize the castor bean as a Cu phytoremediation plant; and iii） to evaluate the nutrient uptake by castor bean. Castor bean plants cultivated in soil with toxic levels of Cu for 57 d exhibited high phytomass production, a high tolerance index of roots＇ fresh mass and shoots＇ dry mass, a high level of Cu phytoaccumulation in the roots and also, a robust capacity for Cu phytostabilization. Furthermore, castor bean plants did not significantly deplete soil nutrients （such as N, P, and Mg） during cultivation. Plants cultivated in Inceptisol, Mollisol and Cu mining waste exhibited a strong potential for Cu phytoaccumulation, with values of 5900, 3 052 and 2805 g ha-1, respectively. In addition, the castor bean＇s elevated phytomass production and strong growth in Cu-contaminated soils indicated a high level of Cu phytoaccumulation and a potential application in biofuels. These findings indicate that the castor bean is a efficient hyperaccumulator of Cu and a potential candidate plant for the phytoremediation of Cu-contaminated soil.展开更多
The effects of processing by autoclaving(AC), soaking(SK), short-term fermentation(S-TF, 4 d) and longterm fermentation(L-TF, 14 d) on the nutritional composition, amino acid profile and some antinutrients were determ...The effects of processing by autoclaving(AC), soaking(SK), short-term fermentation(S-TF, 4 d) and longterm fermentation(L-TF, 14 d) on the nutritional composition, amino acid profile and some antinutrients were determined for cottonseed meal(CSM), groundnut meal(GNM) and groundnut husk(GH) in this study. After processing, crude protein content improved by 11% after L-TF, and crude lipid content 25%after SK for CSM; crude protein content improved by 27% after S-TF and L-TF, and crude lipid content 13%after SK for GNM. Soaking and fermentation were shown to significantly increase essential amino acid contents by 44%(SK, methionine) in CSM and 46% in GNM(L-TF, histidine). Phosphorus content was reduced by 59% in CSM and 57% in GNM by L-TF. All processing techniques, with the exception of AC,reduced phytic acid and gossypol contents in CSM and GNM. It was concluded that SK and fermentation were simple, cost-effective, and efficient ways to improve the nutritional value of the selected oilseed byproducts.展开更多
A 56-day feeding period was performed to investigate the possible impacts of dietary nano curcumin(0,50,100,150,and 200 ppm)on the growth,nutrient utilization,non-specific immune parameters,antioxidants in Nile tilapi...A 56-day feeding period was performed to investigate the possible impacts of dietary nano curcumin(0,50,100,150,and 200 ppm)on the growth,nutrient utilization,non-specific immune parameters,antioxidants in Nile tilapia under chronic low temperature(21.02±0.11◦C).Fishes(n=225;Initial weight=4.39±0.08 g/fish)were randomly stocked at 15 fish/tank for five experimental groups in triplicates.Under low-temperature circumstances,dietary curcumin in nano form showed no notable alteration in growth variable,nutrient efficiency,digestive enzymes efficiency,biometric indices,survival rates,and hematological components.Meanwhile,the serum of fishes with nano curcumin diets under low-temperature stress displayed higher total protein as well as lower glucose,cortisol,and total cholesterol compared with the control group.Moreover,fish fed nano curcumin diets displayed higher lysozyme and bactericidal activities compared to the control group and the best performance was found at dietary nano curcumin level of≥100 ppm.Also,groups fed the basal diet demonstrated the poorest antioxidant capacity,and the best superoxide dismutase(SOD)and glutathione peroxidase(GPx)existed in fish with nano curcumin diets while the best catalase(CAT)efficiency occurred at higher nano curcumin levels≥100 ppm.In addition,higher counts of intestinal microbiota in terms of total bacterial count(TBC),total yeast and molds count(TYMC),and coliform were noticed in fish consumed the basal diet compared to groups fed on nano curcumin diets.In conclusion,incorporating nano curcumin at a level of≥100 mg/kg diet(particularly at 150 mg/kg)improved a non-specific immune response,antioxidant,and healthier gastrointestinal microbiota in Nile tilapia under chronic low-temperature stress.展开更多
Alternative sources of fish oil(FO)are one of the major problems in aquaculture;therefore,the goal of the present study was to examine insect(black soldier fly larvae)oil(BSLO)as a potential replacer of fish/s oy oil ...Alternative sources of fish oil(FO)are one of the major problems in aquaculture;therefore,the goal of the present study was to examine insect(black soldier fly larvae)oil(BSLO)as a potential replacer of fish/s oy oil in juvenile rainbow trout(initial average weight of 32±0.15 g)feed.Four diets were formulated wherein FO(control diet)was completely replaced with either soybean oil(SO)or BSLO,and an additional BSLO-based diet supplemented with 1.5%bile acid(BSLO+BA)were fed to the fish for 10 weeks.Growth performance of the BSLO fed group was similar(P>0.05)to that of the FO and SO fed groups,howeve r,the fish fed BSLO+BA diet registered the lowest growth(P<0.05).Oil sources did not(P>0.05)affect the major nutrient content of whole-body,however,the fatty acid composition of the muscle and liver was influenced(P<0.05),with the highest 14:0,16:0,and total saturated fatty acid detected in BSLO or BSLO+BA fed trout compared to the others(P<0.001).No significant diffe rences were observed in eicosapentaenoic acid+docosahexaenoic acid(EPA+DHA)or total n-3 polyunsaturated fatty acid(PUFA)content in muscle among the groups,whereas,the highest EPA:DHA and n-3:n-6 ratios were detected in the FO group.Gene expression for fatty acid binding protein(fabp),fatty acid synthase(fas),and△5 desaturase in the liver was lower in FO(P<0.05),while BSLO+BA registered the highest△6 expression(P=0.006).Supplementation of BA in the BSLO diet increased superoxide dismutase(SOD)and catalase(CAT)activities compared to the other groups(P<0.05).In conclusion,BSLO could serve as a substitute for FO and SO in rainbow trout diet without negatively impacting growth performance,whole-body composition and nutrient retention,and modulate the expression of fatty acid metabolism-related genes in rainbow trout.展开更多
Multi-strain probiotics provide the most dependable approaches to improve health,immune response,and disease resistance in farmed fishes.In the present study,we examined the effects of multi-species probiotics on the ...Multi-strain probiotics provide the most dependable approaches to improve health,immune response,and disease resistance in farmed fishes.In the present study,we examined the effects of multi-species probiotics on the survival,growth,immune response,and disease resistance of rohu(Labeo rohita)larvae.Newly hatched larvae from the day of first feeding(average weight of 0.003 g)were reared with multi-species probiotics having a combination of Bacillus subtilis(109 colony forming units(cfu)/mL)and Lactobacillus spp.(Lactobacillus plantarum,Lactobacillus buchneri-1011 cfu/mL)in water containing doses of 0(control-C),0.5 mL/L(treatment 1-T1),and 1.0 mL/L(treatment 2-T2)in triplicates for 90 days.After the experiment,a challenge test was performed to assess the fish's resistance to pathogenic Aeromonas veronii.Significantly higher survival was recorded in larvae of treated groups(87%in T2 and 79%in T1)compared to the control(62%).Significantly higher growth performance(weight gain and specific growth rate—SGR)was shown by the probiotic-treated larval groups compared to the control.Probiotic supplementation resulted in significantly higher counts of total viable colony(TVC)and lactic acid bacteria(LAB)in the intestine.Some immunological parameters(mucosal fold fattening,goblet cell abundance,expansion of lamina propria and enterocytes)of the gut were significantly better in probiotic-treated fish.The liver of treated fish showed irregular shape nuclei turning into regular shape and reducing spaces between the hepatic cells.Probiotic-treated fish had the highest post-challenge survival rate(90%)against A.veronii infection.The erythrocytes of challenged fish treated with probiotics had significantly lower frequencies of various nuclear and cellular abnormalities.These findings suggest that multi-species probiotic supplements could improve the survival,growth,health status,and immune response of rohu in the early stages of its development.展开更多
Host associated probiotics(HAPs)provide health benefits to the host when administered as dietary supplement.However,a short-term probiotics application strategy has yet to be optimized.A 90-days study was conducted to...Host associated probiotics(HAPs)provide health benefits to the host when administered as dietary supplement.However,a short-term probiotics application strategy has yet to be optimized.A 90-days study was conducted to evaluate the response of Malaysian mahseer,Tor tambroides post larvae fed with basal diet enriched HAPs for 30-days,and its response following another 60-days feeding with only basal diet.Three experimental diets(Enterococcus faecalis strain 2674(T1),Aeromonas sp.strain A8-29(T2)and E.faecalis strain FC11682(T3))were prepared by spray-coating each HAPs on a basal diet at 1×108 CFU/g feed.Differences in growth performances,whole-body proximate and fatty acid composition,muscle morphometry,and gut morphology were evaluated.Results showed that after 30 days,T3 fish produced highest growth.All HAP treatment groups showed better muscle distribution profile,improved fatty acid composition,and higher villus length,width and area,than control group.After 90 days,the growth of T3 fish was still the highest.Muscle distribution profile and villus growth were higher in HAP treatments,although only total n-6 PUFA,total MUFA,linoleic acids,and linolenic acids in HAP treated fish remained high after probiotics withdrawal.No difference in whole-body proximate composition was observed in both 30 and 90 days.Collective findings demonstrated that short-term application of HAPs at an early stage could be used to boost T.tambroides growth,with E.faecalis strain FC11682 showing the best efficacy.展开更多
Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian populations.However,our knowledge of how MPs affect amphibians is very rudimentar...Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian populations.However,our knowledge of how MPs affect amphibians is very rudimentary,and even more limited is our understanding of their effects in combination with other emerging pollutants.Thus,we aimed to evaluate the possible toxicity of polyethylene MPs(PE-MPs)(alone or in combination with a mix of pollutants)on the health of Physalaemus cuvieri tadpoles.After 30 days of exposure,multiple biomarkers were measured,including morphological,biometric,and developmental indices,behavioral parameters,mutagenicity,cytotoxicity,antioxidant and cholinesterase responses,as well as the uptake and accumulation of PE-MPs in animals.Based on the results,there was no significant change in any of the parameters measured in tadpoles exposed to treatments,but induced stress was observed in tadpoles exposed to PE-MPs combined with themixture of pollutants,reflecting significant changes in physiological and biochemical responses.Through principal component analysis(PCA)and integrated biomarker response(IBR)assessment,effects induced by pollutants in each test group were distinguished,confirming that the exposure of P.cuvieri tadpoles to the PE-MPs in combination with a mix of emerging pollutants induces an enhanced stress response,although the uptake and accumulation of PE-MPs in these animalswas reduced.Thus,our study provides newinsight into the danger to amphibians of MPs coexisting with other pollutants in aquatic environments.展开更多
Soil erosion is a crucial geo-environmental hazard worldwide that affects water quality and agriculture,decreases reservoir storage capacity due to sedimentation,and increases the danger of flooding and landslides.Thu...Soil erosion is a crucial geo-environmental hazard worldwide that affects water quality and agriculture,decreases reservoir storage capacity due to sedimentation,and increases the danger of flooding and landslides.Thus,this study uses geospatial modeling to produce soil erosion susceptibility maps(SESM)for the Hangu region,Khyber Pakhtunkhwa(KPK),Pakistan.The Hangu region,located in the Kohat Plateau of KPK,Pakistan,is particularly susceptible to soil erosion due to its unique geomorphological and climatic characteristics.Moreover,the Hangu region is characterized by a combination of steep slopes,variable rainfall patterns,diverse land use,and distinct soil types,all of which contribute to the complexity and severity of soil erosion processes.These factors necessitate a detailed and region-specific study to develop effective soil conservation strategies.In this research,we detected and mapped 1013 soil erosion points and prepared 12 predisposing factors(elevation,aspect,slope,Normalized Differentiate Vegetation Index(NDVI),drainage network,curvature,Land Use Land Cover(LULC),rainfall,lithology,contour,soil texture,and road network)of soil erosion using GIS platform.Additionally,GIS-based statistical models like the weight of evidence(WOE)and frequency ratio(FR)were applied to produce the SESM for the study area.The SESM was reclassified into four classes,i.e.,low,medium,high,and very high zone.The results of WOE for SESM show that 16.39%,33.02%,29.27%,and 21.30%of areas are covered by low,medium,high,and very high zones,respectively.In contrast,the FR results revealed that 16.50%,24.33%,35.55%,and 23.59%of the areas are occupied by low,medium,high,and very high classes.Furthermore,the reliability of applied models was evaluated using the Area Under Curve(AUC)technique.The validation results utilizing the area under curve showed that the success rate curve(SRC)and predicted rate curve(PRC)for WOE are 82%and 86%,respectively,while SRC and PRC for FR are 85%and 96%,respectively.The validation results revealed that t展开更多
Harmful cyanobacterial blooms cause many ecological disasters worldwide. During the development of cyanobacterial blooms, the diversity and domination of cyanobacterial taxa are of a particular concern. In this study,...Harmful cyanobacterial blooms cause many ecological disasters worldwide. During the development of cyanobacterial blooms, the diversity and domination of cyanobacterial taxa are of a particular concern. In this study, the microbial community structure within a water system, such as in Yuqiao Reservoir and Haihe River in Tianjin City, China, was compared by using next-generation sequencing. A total of 5 001 operational taxonomic units were obtained and clustered from filtered 16 S rDNA V3–V4 region sequences. The cyanobacterial and microbial structures greatly differed in these two water areas. Microcystis was dominant in Yuqiao, whereas Synechococcus was dominant in Haihe. Proteobacteria species were dominant among all detected samples. The relative abundances of Bacteroidetes and Planctomycetes were higher in Yuqiao Reservoir than in Haihe River, whereas Firmicutes and Verrucomicrobia were relatively abundant in Haihe River. Further analyses indicated that the domination of both cyanobacteria was strongly related to several environmental factors, such as total nitrogen, total phosphorus, and dissolved oxygen, reflecting the role of trophic states in shaping the dominance of cyanobacterial taxa. The present study provided the example for Microcystis and Synechococcus dominance along a cyanobacterial bloom in north China. Applying highthroughput sequencing could offer a wide field of vision in analyzing microbial community structures.展开更多
From 20 January to 20 July 2023, a study was carried out on the Lobé Creek, a waterway subject to considerable natural and man-made pressures, with a negative impact on its biodiversity and habitats. The aim was ...From 20 January to 20 July 2023, a study was carried out on the Lobé Creek, a waterway subject to considerable natural and man-made pressures, with a negative impact on its biodiversity and habitats. The aim was to evaluate the growth rate of invasive aquatic macrophytes and their contribution to the use of organic fertilisers: a case of Eicchornia crassipes (Mart.) Solms, 1883 in the Lobé Creek (Littoral-Cameroon) with a view to its appropriate use in agronomy. The specific objective was to examine the impact of anthropogenic actions on Lobé Creek, characterise physico-chemical environment of the study area, and evaluate the growth rate of E. crassipes and its chemical composition with a view to producing an organic biofertiliser. The results show that E. crassipes represents a considerable threat to the populations of these localities. As for the physico-chemical parameters, the temperature values vary from 24 ± 1.41˚C to 26.5 ± 1.13˚C;pH from 6.3 ± 0.1 to 7.2 ± 0.07;conductivity and dissolved oxygen vary respectively from 40.7 ± 1.83 µS/cm to 19.6 ± 3.11 µS/cm and from 7.3 ± 0.14 mg/l to 5.8 ± 1.55 mg/l. Its average growth rate varies from 0.69 feet/day to 0.63 feet/day. With regard to the nitrogen, phosphorus and potassium content of water hyacinth plants, the results show that the average total nitrogen content ranges from 6.11 ± 1.59 g/kg to 5.2 ± 2.03 g/kg;total phosphorus, from 0.52 ± 0.54 g/kg to 0.88 ± 0.38 g/kg;and potassium, from 1.43 ± 0.45 g/kg to 2.61 ± 0.89 g/kg.展开更多
Objective:To investigate the effect of the hexane solvent fraction of Halymenia durvillei(HDHE)on triple-negative breast cancer.Methods:The phytochemical profile of HDHE was investigated by GC-MS.The cytotoxicity of H...Objective:To investigate the effect of the hexane solvent fraction of Halymenia durvillei(HDHE)on triple-negative breast cancer.Methods:The phytochemical profile of HDHE was investigated by GC-MS.The cytotoxicity of HDHE against MDA-MB-231 cells was determined.The apoptotic and autophagic effects of HDHE were analyzed.The expression of molecular markers controlling apoptosis,autophagy,DNA damage,and endoplasmic reticulum(ER)stress was determined.Results:HDHE contains a mixture of fatty acids,mainly hexadecanoic acid.HDHE at a cytotoxic concentration induced apoptotic death of MDA-MB-231 cells through mitochondrial membrane dysfunction,and induction of apoptosis markers,and increased the expression of proteins related to DNA damage response.HDHE also induced the expression of LC-3,a marker of autophagic cell death at a cytotoxic concentration.Moreover,HDHE modulated the expression of ER stress genes.Conclusions:The hexadecanoic acid-enriched extract of Halymenia durvillei promotes apoptosis and autophagy of human triple-negative breast cancer cells.This extract may be further explored as an anticancer agent for triple-negative breast cancer.展开更多
Freshwater bodies are natural resources that should be exploited to the fullest, while maintaining the sustainability of ecosystems and ecosystem services which they support. Riparian forests are more important as the...Freshwater bodies are natural resources that should be exploited to the fullest, while maintaining the sustainability of ecosystems and ecosystem services which they support. Riparian forests are more important as they contain rivers which are vital sources of fresh water for local populations. However, the quality and quantity of water issued from the watershed depend on the structural state of these forests. The aim of this work was to assess the physico-chemical and structural state of the Akono gallery forest. To achieve this, fieldwork consisted of selecting six major streams of the watershed including Ndjolong, Menyeng adzap, Emomodo, Mvila, Negbe and Ossoé kobok. On each of these, two stations, one intact and one degraded, were marked by transects. The method involved measuring Hydrometric parameters (depth, length, width) of the stream and Physico-chemical parameters of water in the streams while dendrometric parameters were measured along 100 m-transects laid using the point-centred quarter method modified for water bodies to collect tree, shrub and palm variables such as trunk diameter, crown diameter and height. Macrophytes and species identification were carried out using standard botanical procedures. Results showed that, the majority of physico-chemical parameters measured differed significantly between intact and degraded stations (P Pentachletra mancrophylla, whereas on degraded sites, this index was low and characterized by the relative dominance of species Piptadeniastrum africanum. Sorensen’s index (0.56) and CFA showed that the different stands were homogeneous. We can affirm that the riparian forests of Akono watershed are towards a state of stability notwithstanding the perpetuation of anthropological actions.展开更多
Tilapia Lake Virus(TiLV)disease is an emerging and transboundary disease of tilapia cultures,causing mortality up to 90%globally.TiLV is a negative sense single stranded RNA virus belongs to family Amnoonviridae,genus...Tilapia Lake Virus(TiLV)disease is an emerging and transboundary disease of tilapia cultures,causing mortality up to 90%globally.TiLV is a negative sense single stranded RNA virus belongs to family Amnoonviridae,genus Tilapinevirus and species Tilapia tilapinevirus.The first TiLV outbreak to fishes was reported from Israel followed by other countries viz.,Ecuador,Colombia,Egypt,Thailand,Chinese Taipei,India,Malaysia,Bangladesh,Uganda,Tanzania,Peru,Mexico,Philippines,Indonesia,and USA.All the life stages of Tilapia(belonging to the family Cichlidae)are vulnerable to TiLV infection.However,river barb and giant gourami have also been found susceptible to TiLV infection.The virus infects the vital organs of the fish,including eyes,brain,and liver.The notable pathological finding of this disease includes syncytial cell formation and massive hepatocellular necrosis with pyknotic and karyolytic nuclei in the liver cells of infected fish.The disease is very contagious and spreads through both horizontal and vertical transmission.Several sensitive and rapid molecular diagnostic tools like reverse transcriptase polymerase chain reaction(RT-PCR),RT-quantitative PCR(RT-qPCR),loop-mediated isothermal amplification(LAMP)have been developed for early detection of the virus.Till date,no comprehensive control measures have been developed throughout the globe,although aggressive work on this line is going on.Implementations of strict good management practices,including quarantine protocols,are the only available option to combat the outbreak and spread of the disease.This review emphasizes the etiology,occurrence and distribution,mode of transmission,pathology and pathogenesis,diagnosis,possible control measures,and challenges of TiLV disease.展开更多
This study comprehensively assessed long-term vegetation changes and forest fragmentation dynamics in the Himalayan temperate region of Pakistan from 1989 to 2019.Four satellite images,including Landsat-5 TM and Lands...This study comprehensively assessed long-term vegetation changes and forest fragmentation dynamics in the Himalayan temperate region of Pakistan from 1989 to 2019.Four satellite images,including Landsat-5 TM and Landsat-8 Operational Land Imager(OLI),were chosen for subsequent assessments in October 1989,2001,2011 and 2019.The classified maps of 1989,2001,2011 and 2019 were created using the maximum likelihood classifier.Post-classification comparison showed an overall accuracy of 82.5%and a Kappa coefficient of 0.79 for the 2019 map.Results revealed a drastic decrease in closed-canopy and open-canopy forests by 117.4 and 271.6 km^(2),respectively,and an increase in agriculture/farm cultivation by 1512.8 km^(2).The two-way ANOVA test showed statistically significant differences in the area of various cover classes.Forest fragmentation was evaluated using the Landscape Fragmentation Tool(LFT v2.0)between 1989 and 2019.The large forest core(>2.00 km^(2))decreased from 149.4 to 296.7 km^(2),and a similar pattern was observed in medium forest core(1.00-2.00 km^(2))forests.On the contrary,the small core(<1.00 km^(2))forest increased from 124.8 to 145.3 km^(2) in 2019.The perforation area increased by 296.9 km^(2),and the edge effect decreased from 458.9 to 431.7 km^(2).The frequency of patches also increased by 119.1 km^(2).The closed and open canopy classes showed a decreasing trend with an annual rate of 0.58%and 1.35%,respectively.The broad implications of these findings can be seen in the studied region as well as other global ecological areas.They serve as an imperative baseline for afforestation and reforestation operations,highlighting the urgent need for efficient management,conservation,and restoration efforts.Based on these findings,sustainable land-use policies may be put into place that support local livelihoods,protect ecosystem services,and conserve biodiversity.展开更多
Crassostrea(Magallana)saidii has been commercially ranched in Malaysia and consumed for more than 160 years,but it was only recently identified as a new species to science.This study was conducted to evaluate the repr...Crassostrea(Magallana)saidii has been commercially ranched in Malaysia and consumed for more than 160 years,but it was only recently identified as a new species to science.This study was conducted to evaluate the reproductive phenology of C.(M.)saidii.Samples of 30 individual oysters were taken monthly for 15 months from the sole population at Sungai Muar estuary in Johor,Malaysia.The sex ratio was 1:1.64(male:female)for all examined specimens,with female numbers significantly higher.Hermaphrodism was detected in 1.56%of all samples.Spawning peaks in April(2019)and November(2018 and 2019),and were positively associated with the increased rainfall upstream.Gametogenesis occurred throughout the research period with temporal variations.The highest values of maturity index(MI)were recorded in March,August and October 2019,when most oysters were in matured and maturing stages.Condition index(CI)ranged from 31.90±1.25(April 2019)to 70.03±3.23(October 2019),exhibiting two peaks(March and October 2019)and subsequently reduced in CI indicating spawning consistency with histological observations.Anthropogenic stressors such as heavy sedimentation and inland development are threatening the survival of this species.The understanding of their reproductive biology is essential to ensure the survival and sustainability of C.(M.)saidii fishery.展开更多
A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog （Rana catesbeiana） cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella sp...A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog （Rana catesbeiana） cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella spp. （46 isolates） followed by Aeromonas spp. （33 isolates）, Flavobacterium spp. （31 isolates）, and Vibrio spp. （30 isolates）. Majority of the bacterial isolates were found sensitive to furazolidone （85.0%）, chloramphenicol （85.0%）, oxolinic acid （90.0%）, florfenicol （95.0%）, and flumequine （97.5%）. On the other hand, most of the bacterial isolates were resistant to oleandomycin （77.5%） and lincomycin （87.5%）. Nitrofurantoin and flumequine can be inhibited the growth of all of Vibrio spp. whereas all isolates of Edwardsiella spp. were found sensitive to florfenicol and flumequine. Multiple antibiotic resistance （MAR） index were in range of 0.30-0.40, indicating that bacterial isolates from cultured bullfrogs may have received high risk exposure to the tested antibiotics. In addition, 90-100% of the isolates were resistant to copper, cadmium, and chromium. These results provided insight information on tolerance level of bacterial isolates from cultured bullfrogs to 21 antibiotics as well as heavy metals.展开更多
文摘The intensification of aquaculture has emerged as a viable alternative for increasing aquaculture production due to competition that arose from the use of natural resources,such as land and water,by other production and developmental sectors.However,intensification demands increased inputs,such as fish and feed per unit culture area and,therefore,increased waste generation from the aquaculture production systems.The impact of waste products from aquaculture has increased public concern and threatens the sustainability of aquaculture practices.The need for increasing the production of aquaculture products cannot be overemphasized and,therefore,there is a need to develop culture systems that will increase fish production with efficient waste management in order to limit environmental degradation resulting from aquaculture wastes and ensure its sustainability.This paper reviewed various aspects of waste production from aquaculture,their sources,components,and methods of management,in different culture systems,primarily discussing waste production from feed,chemicals,and pathogens.We aimed to establish the sources of wastes,their contents,and potential harms to both the fish culture and the environment.Suggestions for managing wastes in different culture systems were made to ensure an improved and sustainable aquaculture production.
基金funded by the Ministry of Education of Malaysia under the Fundamental Research Grant Scheme(FRGS)(R/FRGS/A07.00/00387A/005/2013/00107)Niche Research Grant Scheme(NRGS)(R/NRGS/A0.700/00387A/006/2014/00152)partially supported by Chiang Mai University。
文摘The aquafeed industry continues to expand in response to the rapidly growing aquaculture sector.However,the identification of alternative protein sources in aquatic animal diets to replace conventional sources due to cost and sustainability issues remains a major challenge.Recently,insects have shown tremendous results as potential replacers of fishmeal in aquafeed.The present study aimed to review the utilization of insects in aquafeeds and their effects on aquatic animals’growth and feed utilization,immune response and disease resistance,and fish flesh quality and safety.While many insect species have been investigated in aquaculture,the black soldier fly(Hermetia illucens),and the mealworm(Tenebrio molitor)are the most studied and most promising insects to replace fishmeal in aquafeed.Generally,insect rearing conditions and biomass processing methods may affect the product’s nutritional composition,digestibility,shelf life and required insect inclusion level by aquatic animals.Also,insect-recommended inclusion levels for aquatic animals vary depending on the insect species used,biomass processing method,and test organism.Overall,while an appropriate inclusion level of insects in aquafeed provides several nutritional and health benefits to aquatic animals,more studies are needed to establish optimum requirements levels for different aquaculture species at different stages of development and under different culture systems.
基金Supported by the Coordenao de Aperfeic oamento de Pessoal de N'vel Superior (CAPES) of Brazil and the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) of Brazil
文摘Copper （Cu） contamination in the environment has been increased during the years with agricultural and industrial activities. Biotechnological approaches are needed for bioremediation in these areas. The aims of this study were i） to evaluate the phytoreme- diation capacity of the high-yielding bioenergy plant castor bean （Ricinus communis L.） in vineyard soils （Inceptisol and Mollisol） contaminated with Cu and a Cu mining waste; ii） to characterize the castor bean as a Cu phytoremediation plant; and iii） to evaluate the nutrient uptake by castor bean. Castor bean plants cultivated in soil with toxic levels of Cu for 57 d exhibited high phytomass production, a high tolerance index of roots＇ fresh mass and shoots＇ dry mass, a high level of Cu phytoaccumulation in the roots and also, a robust capacity for Cu phytostabilization. Furthermore, castor bean plants did not significantly deplete soil nutrients （such as N, P, and Mg） during cultivation. Plants cultivated in Inceptisol, Mollisol and Cu mining waste exhibited a strong potential for Cu phytoaccumulation, with values of 5900, 3 052 and 2805 g ha-1, respectively. In addition, the castor bean＇s elevated phytomass production and strong growth in Cu-contaminated soils indicated a high level of Cu phytoaccumulation and a potential application in biofuels. These findings indicate that the castor bean is a efficient hyperaccumulator of Cu and a potential candidate plant for the phytoremediation of Cu-contaminated soil.
基金a part of CPDs PhD supported by the Danish International Development Agency(DANIDA)(grant number DFC No.13-PO1-GHA)
文摘The effects of processing by autoclaving(AC), soaking(SK), short-term fermentation(S-TF, 4 d) and longterm fermentation(L-TF, 14 d) on the nutritional composition, amino acid profile and some antinutrients were determined for cottonseed meal(CSM), groundnut meal(GNM) and groundnut husk(GH) in this study. After processing, crude protein content improved by 11% after L-TF, and crude lipid content 25%after SK for CSM; crude protein content improved by 27% after S-TF and L-TF, and crude lipid content 13%after SK for GNM. Soaking and fermentation were shown to significantly increase essential amino acid contents by 44%(SK, methionine) in CSM and 46% in GNM(L-TF, histidine). Phosphorus content was reduced by 59% in CSM and 57% in GNM by L-TF. All processing techniques, with the exception of AC,reduced phytic acid and gossypol contents in CSM and GNM. It was concluded that SK and fermentation were simple, cost-effective, and efficient ways to improve the nutritional value of the selected oilseed byproducts.
文摘A 56-day feeding period was performed to investigate the possible impacts of dietary nano curcumin(0,50,100,150,and 200 ppm)on the growth,nutrient utilization,non-specific immune parameters,antioxidants in Nile tilapia under chronic low temperature(21.02±0.11◦C).Fishes(n=225;Initial weight=4.39±0.08 g/fish)were randomly stocked at 15 fish/tank for five experimental groups in triplicates.Under low-temperature circumstances,dietary curcumin in nano form showed no notable alteration in growth variable,nutrient efficiency,digestive enzymes efficiency,biometric indices,survival rates,and hematological components.Meanwhile,the serum of fishes with nano curcumin diets under low-temperature stress displayed higher total protein as well as lower glucose,cortisol,and total cholesterol compared with the control group.Moreover,fish fed nano curcumin diets displayed higher lysozyme and bactericidal activities compared to the control group and the best performance was found at dietary nano curcumin level of≥100 ppm.Also,groups fed the basal diet demonstrated the poorest antioxidant capacity,and the best superoxide dismutase(SOD)and glutathione peroxidase(GPx)existed in fish with nano curcumin diets while the best catalase(CAT)efficiency occurred at higher nano curcumin levels≥100 ppm.In addition,higher counts of intestinal microbiota in terms of total bacterial count(TBC),total yeast and molds count(TYMC),and coliform were noticed in fish consumed the basal diet compared to groups fed on nano curcumin diets.In conclusion,incorporating nano curcumin at a level of≥100 mg/kg diet(particularly at 150 mg/kg)improved a non-specific immune response,antioxidant,and healthier gastrointestinal microbiota in Nile tilapia under chronic low-temperature stress.
基金the J.William Fulbright Scholarship Program for financial support as a Visiting Scholar at Aquaculture Research Institute,University of Idaho,USAthe United States Department of Agriculture Agricultural Research Service for partially funding the research(Accession numbers:437676&436723)。
文摘Alternative sources of fish oil(FO)are one of the major problems in aquaculture;therefore,the goal of the present study was to examine insect(black soldier fly larvae)oil(BSLO)as a potential replacer of fish/s oy oil in juvenile rainbow trout(initial average weight of 32±0.15 g)feed.Four diets were formulated wherein FO(control diet)was completely replaced with either soybean oil(SO)or BSLO,and an additional BSLO-based diet supplemented with 1.5%bile acid(BSLO+BA)were fed to the fish for 10 weeks.Growth performance of the BSLO fed group was similar(P>0.05)to that of the FO and SO fed groups,howeve r,the fish fed BSLO+BA diet registered the lowest growth(P<0.05).Oil sources did not(P>0.05)affect the major nutrient content of whole-body,however,the fatty acid composition of the muscle and liver was influenced(P<0.05),with the highest 14:0,16:0,and total saturated fatty acid detected in BSLO or BSLO+BA fed trout compared to the others(P<0.001).No significant diffe rences were observed in eicosapentaenoic acid+docosahexaenoic acid(EPA+DHA)or total n-3 polyunsaturated fatty acid(PUFA)content in muscle among the groups,whereas,the highest EPA:DHA and n-3:n-6 ratios were detected in the FO group.Gene expression for fatty acid binding protein(fabp),fatty acid synthase(fas),and△5 desaturase in the liver was lower in FO(P<0.05),while BSLO+BA registered the highest△6 expression(P=0.006).Supplementation of BA in the BSLO diet increased superoxide dismutase(SOD)and catalase(CAT)activities compared to the other groups(P<0.05).In conclusion,BSLO could serve as a substitute for FO and SO in rainbow trout diet without negatively impacting growth performance,whole-body composition and nutrient retention,and modulate the expression of fatty acid metabolism-related genes in rainbow trout.
基金Krishi Gobeshona Foundation,Bangladesh Agricultural Research Council,Dhaka,supported a grant(CGP TF 75-F/20)the corresponding author.Bangladesh Agricultural University Research System(BAURES)is gratefully acknowledged for the financial management of this project(Project No.2020/954/KGF).
文摘Multi-strain probiotics provide the most dependable approaches to improve health,immune response,and disease resistance in farmed fishes.In the present study,we examined the effects of multi-species probiotics on the survival,growth,immune response,and disease resistance of rohu(Labeo rohita)larvae.Newly hatched larvae from the day of first feeding(average weight of 0.003 g)were reared with multi-species probiotics having a combination of Bacillus subtilis(109 colony forming units(cfu)/mL)and Lactobacillus spp.(Lactobacillus plantarum,Lactobacillus buchneri-1011 cfu/mL)in water containing doses of 0(control-C),0.5 mL/L(treatment 1-T1),and 1.0 mL/L(treatment 2-T2)in triplicates for 90 days.After the experiment,a challenge test was performed to assess the fish's resistance to pathogenic Aeromonas veronii.Significantly higher survival was recorded in larvae of treated groups(87%in T2 and 79%in T1)compared to the control(62%).Significantly higher growth performance(weight gain and specific growth rate—SGR)was shown by the probiotic-treated larval groups compared to the control.Probiotic supplementation resulted in significantly higher counts of total viable colony(TVC)and lactic acid bacteria(LAB)in the intestine.Some immunological parameters(mucosal fold fattening,goblet cell abundance,expansion of lamina propria and enterocytes)of the gut were significantly better in probiotic-treated fish.The liver of treated fish showed irregular shape nuclei turning into regular shape and reducing spaces between the hepatic cells.Probiotic-treated fish had the highest post-challenge survival rate(90%)against A.veronii infection.The erythrocytes of challenged fish treated with probiotics had significantly lower frequencies of various nuclear and cellular abnormalities.These findings suggest that multi-species probiotic supplements could improve the survival,growth,health status,and immune response of rohu in the early stages of its development.
基金funded by Universiti Malaysia Terengganu under the Research Intensified Grant Scheme (RIGS VOT NO 55192/5).
文摘Host associated probiotics(HAPs)provide health benefits to the host when administered as dietary supplement.However,a short-term probiotics application strategy has yet to be optimized.A 90-days study was conducted to evaluate the response of Malaysian mahseer,Tor tambroides post larvae fed with basal diet enriched HAPs for 30-days,and its response following another 60-days feeding with only basal diet.Three experimental diets(Enterococcus faecalis strain 2674(T1),Aeromonas sp.strain A8-29(T2)and E.faecalis strain FC11682(T3))were prepared by spray-coating each HAPs on a basal diet at 1×108 CFU/g feed.Differences in growth performances,whole-body proximate and fatty acid composition,muscle morphometry,and gut morphology were evaluated.Results showed that after 30 days,T3 fish produced highest growth.All HAP treatment groups showed better muscle distribution profile,improved fatty acid composition,and higher villus length,width and area,than control group.After 90 days,the growth of T3 fish was still the highest.Muscle distribution profile and villus growth were higher in HAP treatments,although only total n-6 PUFA,total MUFA,linoleic acids,and linolenic acids in HAP treated fish remained high after probiotics withdrawal.No difference in whole-body proximate composition was observed in both 30 and 90 days.Collective findings demonstrated that short-term application of HAPs at an early stage could be used to boost T.tambroides growth,with E.faecalis strain FC11682 showing the best efficacy.
基金supporting the financing of this study(Process#307743/2018–7)the granting of research productivity grants to Dr.Malafaia G.(Proc.#307743/2018–7)and Dr.Melo e Silva D.(Process#307652/2018-1)+1 种基金for the scientific initiation scholarships to students Silva A.M.and Luz T.M.In addition,the authors thank the Federal Institute of Goiano(GO,Brazil)granting important financial assistance for the publication of this study(Proc.#23219.000139.2022-17).
文摘Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian populations.However,our knowledge of how MPs affect amphibians is very rudimentary,and even more limited is our understanding of their effects in combination with other emerging pollutants.Thus,we aimed to evaluate the possible toxicity of polyethylene MPs(PE-MPs)(alone or in combination with a mix of pollutants)on the health of Physalaemus cuvieri tadpoles.After 30 days of exposure,multiple biomarkers were measured,including morphological,biometric,and developmental indices,behavioral parameters,mutagenicity,cytotoxicity,antioxidant and cholinesterase responses,as well as the uptake and accumulation of PE-MPs in animals.Based on the results,there was no significant change in any of the parameters measured in tadpoles exposed to treatments,but induced stress was observed in tadpoles exposed to PE-MPs combined with themixture of pollutants,reflecting significant changes in physiological and biochemical responses.Through principal component analysis(PCA)and integrated biomarker response(IBR)assessment,effects induced by pollutants in each test group were distinguished,confirming that the exposure of P.cuvieri tadpoles to the PE-MPs in combination with a mix of emerging pollutants induces an enhanced stress response,although the uptake and accumulation of PE-MPs in these animalswas reduced.Thus,our study provides newinsight into the danger to amphibians of MPs coexisting with other pollutants in aquatic environments.
基金The authors extend their appreciation to Researchers Supporting Project number(RSP2024R390),King Saud University,Riyadh,Saudi Arabia.
文摘Soil erosion is a crucial geo-environmental hazard worldwide that affects water quality and agriculture,decreases reservoir storage capacity due to sedimentation,and increases the danger of flooding and landslides.Thus,this study uses geospatial modeling to produce soil erosion susceptibility maps(SESM)for the Hangu region,Khyber Pakhtunkhwa(KPK),Pakistan.The Hangu region,located in the Kohat Plateau of KPK,Pakistan,is particularly susceptible to soil erosion due to its unique geomorphological and climatic characteristics.Moreover,the Hangu region is characterized by a combination of steep slopes,variable rainfall patterns,diverse land use,and distinct soil types,all of which contribute to the complexity and severity of soil erosion processes.These factors necessitate a detailed and region-specific study to develop effective soil conservation strategies.In this research,we detected and mapped 1013 soil erosion points and prepared 12 predisposing factors(elevation,aspect,slope,Normalized Differentiate Vegetation Index(NDVI),drainage network,curvature,Land Use Land Cover(LULC),rainfall,lithology,contour,soil texture,and road network)of soil erosion using GIS platform.Additionally,GIS-based statistical models like the weight of evidence(WOE)and frequency ratio(FR)were applied to produce the SESM for the study area.The SESM was reclassified into four classes,i.e.,low,medium,high,and very high zone.The results of WOE for SESM show that 16.39%,33.02%,29.27%,and 21.30%of areas are covered by low,medium,high,and very high zones,respectively.In contrast,the FR results revealed that 16.50%,24.33%,35.55%,and 23.59%of the areas are occupied by low,medium,high,and very high classes.Furthermore,the reliability of applied models was evaluated using the Area Under Curve(AUC)technique.The validation results utilizing the area under curve showed that the success rate curve(SRC)and predicted rate curve(PRC)for WOE are 82%and 86%,respectively,while SRC and PRC for FR are 85%and 96%,respectively.The validation results revealed that t
基金Supported by the International Science&Technology Cooperation Program of China(No.2013DFA71340)the National Natural Science Foundation of China(No.51779247)
文摘Harmful cyanobacterial blooms cause many ecological disasters worldwide. During the development of cyanobacterial blooms, the diversity and domination of cyanobacterial taxa are of a particular concern. In this study, the microbial community structure within a water system, such as in Yuqiao Reservoir and Haihe River in Tianjin City, China, was compared by using next-generation sequencing. A total of 5 001 operational taxonomic units were obtained and clustered from filtered 16 S rDNA V3–V4 region sequences. The cyanobacterial and microbial structures greatly differed in these two water areas. Microcystis was dominant in Yuqiao, whereas Synechococcus was dominant in Haihe. Proteobacteria species were dominant among all detected samples. The relative abundances of Bacteroidetes and Planctomycetes were higher in Yuqiao Reservoir than in Haihe River, whereas Firmicutes and Verrucomicrobia were relatively abundant in Haihe River. Further analyses indicated that the domination of both cyanobacteria was strongly related to several environmental factors, such as total nitrogen, total phosphorus, and dissolved oxygen, reflecting the role of trophic states in shaping the dominance of cyanobacterial taxa. The present study provided the example for Microcystis and Synechococcus dominance along a cyanobacterial bloom in north China. Applying highthroughput sequencing could offer a wide field of vision in analyzing microbial community structures.
文摘From 20 January to 20 July 2023, a study was carried out on the Lobé Creek, a waterway subject to considerable natural and man-made pressures, with a negative impact on its biodiversity and habitats. The aim was to evaluate the growth rate of invasive aquatic macrophytes and their contribution to the use of organic fertilisers: a case of Eicchornia crassipes (Mart.) Solms, 1883 in the Lobé Creek (Littoral-Cameroon) with a view to its appropriate use in agronomy. The specific objective was to examine the impact of anthropogenic actions on Lobé Creek, characterise physico-chemical environment of the study area, and evaluate the growth rate of E. crassipes and its chemical composition with a view to producing an organic biofertiliser. The results show that E. crassipes represents a considerable threat to the populations of these localities. As for the physico-chemical parameters, the temperature values vary from 24 ± 1.41˚C to 26.5 ± 1.13˚C;pH from 6.3 ± 0.1 to 7.2 ± 0.07;conductivity and dissolved oxygen vary respectively from 40.7 ± 1.83 µS/cm to 19.6 ± 3.11 µS/cm and from 7.3 ± 0.14 mg/l to 5.8 ± 1.55 mg/l. Its average growth rate varies from 0.69 feet/day to 0.63 feet/day. With regard to the nitrogen, phosphorus and potassium content of water hyacinth plants, the results show that the average total nitrogen content ranges from 6.11 ± 1.59 g/kg to 5.2 ± 2.03 g/kg;total phosphorus, from 0.52 ± 0.54 g/kg to 0.88 ± 0.38 g/kg;and potassium, from 1.43 ± 0.45 g/kg to 2.61 ± 0.89 g/kg.
基金the National Research Council of Thailand to Rapeewan Settacomkul(No.13/2563)Faculty of Medicine,Thammasat University to Kant Sangpairoj(No.2-20/2563).
文摘Objective:To investigate the effect of the hexane solvent fraction of Halymenia durvillei(HDHE)on triple-negative breast cancer.Methods:The phytochemical profile of HDHE was investigated by GC-MS.The cytotoxicity of HDHE against MDA-MB-231 cells was determined.The apoptotic and autophagic effects of HDHE were analyzed.The expression of molecular markers controlling apoptosis,autophagy,DNA damage,and endoplasmic reticulum(ER)stress was determined.Results:HDHE contains a mixture of fatty acids,mainly hexadecanoic acid.HDHE at a cytotoxic concentration induced apoptotic death of MDA-MB-231 cells through mitochondrial membrane dysfunction,and induction of apoptosis markers,and increased the expression of proteins related to DNA damage response.HDHE also induced the expression of LC-3,a marker of autophagic cell death at a cytotoxic concentration.Moreover,HDHE modulated the expression of ER stress genes.Conclusions:The hexadecanoic acid-enriched extract of Halymenia durvillei promotes apoptosis and autophagy of human triple-negative breast cancer cells.This extract may be further explored as an anticancer agent for triple-negative breast cancer.
文摘Freshwater bodies are natural resources that should be exploited to the fullest, while maintaining the sustainability of ecosystems and ecosystem services which they support. Riparian forests are more important as they contain rivers which are vital sources of fresh water for local populations. However, the quality and quantity of water issued from the watershed depend on the structural state of these forests. The aim of this work was to assess the physico-chemical and structural state of the Akono gallery forest. To achieve this, fieldwork consisted of selecting six major streams of the watershed including Ndjolong, Menyeng adzap, Emomodo, Mvila, Negbe and Ossoé kobok. On each of these, two stations, one intact and one degraded, were marked by transects. The method involved measuring Hydrometric parameters (depth, length, width) of the stream and Physico-chemical parameters of water in the streams while dendrometric parameters were measured along 100 m-transects laid using the point-centred quarter method modified for water bodies to collect tree, shrub and palm variables such as trunk diameter, crown diameter and height. Macrophytes and species identification were carried out using standard botanical procedures. Results showed that, the majority of physico-chemical parameters measured differed significantly between intact and degraded stations (P Pentachletra mancrophylla, whereas on degraded sites, this index was low and characterized by the relative dominance of species Piptadeniastrum africanum. Sorensen’s index (0.56) and CFA showed that the different stands were homogeneous. We can affirm that the riparian forests of Akono watershed are towards a state of stability notwithstanding the perpetuation of anthropological actions.
基金the Dean,College of Fisheries,CAU(Imphal),Lembucherra,Tripura,799210,IndiaDirector ICAR-CIFA,Bhubaneswar,751002,India for providing the necessary facilities.
文摘Tilapia Lake Virus(TiLV)disease is an emerging and transboundary disease of tilapia cultures,causing mortality up to 90%globally.TiLV is a negative sense single stranded RNA virus belongs to family Amnoonviridae,genus Tilapinevirus and species Tilapia tilapinevirus.The first TiLV outbreak to fishes was reported from Israel followed by other countries viz.,Ecuador,Colombia,Egypt,Thailand,Chinese Taipei,India,Malaysia,Bangladesh,Uganda,Tanzania,Peru,Mexico,Philippines,Indonesia,and USA.All the life stages of Tilapia(belonging to the family Cichlidae)are vulnerable to TiLV infection.However,river barb and giant gourami have also been found susceptible to TiLV infection.The virus infects the vital organs of the fish,including eyes,brain,and liver.The notable pathological finding of this disease includes syncytial cell formation and massive hepatocellular necrosis with pyknotic and karyolytic nuclei in the liver cells of infected fish.The disease is very contagious and spreads through both horizontal and vertical transmission.Several sensitive and rapid molecular diagnostic tools like reverse transcriptase polymerase chain reaction(RT-PCR),RT-quantitative PCR(RT-qPCR),loop-mediated isothermal amplification(LAMP)have been developed for early detection of the virus.Till date,no comprehensive control measures have been developed throughout the globe,although aggressive work on this line is going on.Implementations of strict good management practices,including quarantine protocols,are the only available option to combat the outbreak and spread of the disease.This review emphasizes the etiology,occurrence and distribution,mode of transmission,pathology and pathogenesis,diagnosis,possible control measures,and challenges of TiLV disease.
基金This research was supported by project number(RSP2024R384)King Saud University,Riyadh,Saudi Arabia.
文摘This study comprehensively assessed long-term vegetation changes and forest fragmentation dynamics in the Himalayan temperate region of Pakistan from 1989 to 2019.Four satellite images,including Landsat-5 TM and Landsat-8 Operational Land Imager(OLI),were chosen for subsequent assessments in October 1989,2001,2011 and 2019.The classified maps of 1989,2001,2011 and 2019 were created using the maximum likelihood classifier.Post-classification comparison showed an overall accuracy of 82.5%and a Kappa coefficient of 0.79 for the 2019 map.Results revealed a drastic decrease in closed-canopy and open-canopy forests by 117.4 and 271.6 km^(2),respectively,and an increase in agriculture/farm cultivation by 1512.8 km^(2).The two-way ANOVA test showed statistically significant differences in the area of various cover classes.Forest fragmentation was evaluated using the Landscape Fragmentation Tool(LFT v2.0)between 1989 and 2019.The large forest core(>2.00 km^(2))decreased from 149.4 to 296.7 km^(2),and a similar pattern was observed in medium forest core(1.00-2.00 km^(2))forests.On the contrary,the small core(<1.00 km^(2))forest increased from 124.8 to 145.3 km^(2) in 2019.The perforation area increased by 296.9 km^(2),and the edge effect decreased from 458.9 to 431.7 km^(2).The frequency of patches also increased by 119.1 km^(2).The closed and open canopy classes showed a decreasing trend with an annual rate of 0.58%and 1.35%,respectively.The broad implications of these findings can be seen in the studied region as well as other global ecological areas.They serve as an imperative baseline for afforestation and reforestation operations,highlighting the urgent need for efficient management,conservation,and restoration efforts.Based on these findings,sustainable land-use policies may be put into place that support local livelihoods,protect ecosystem services,and conserve biodiversity.
文摘Crassostrea(Magallana)saidii has been commercially ranched in Malaysia and consumed for more than 160 years,but it was only recently identified as a new species to science.This study was conducted to evaluate the reproductive phenology of C.(M.)saidii.Samples of 30 individual oysters were taken monthly for 15 months from the sole population at Sungai Muar estuary in Johor,Malaysia.The sex ratio was 1:1.64(male:female)for all examined specimens,with female numbers significantly higher.Hermaphrodism was detected in 1.56%of all samples.Spawning peaks in April(2019)and November(2018 and 2019),and were positively associated with the increased rainfall upstream.Gametogenesis occurred throughout the research period with temporal variations.The highest values of maturity index(MI)were recorded in March,August and October 2019,when most oysters were in matured and maturing stages.Condition index(CI)ranged from 31.90±1.25(April 2019)to 70.03±3.23(October 2019),exhibiting two peaks(March and October 2019)and subsequently reduced in CI indicating spawning consistency with histological observations.Anthropogenic stressors such as heavy sedimentation and inland development are threatening the survival of this species.The understanding of their reproductive biology is essential to ensure the survival and sustainability of C.(M.)saidii fishery.
基金funded by Universiti Malaysia Terengganu, Malaysia
文摘A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog （Rana catesbeiana） cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella spp. （46 isolates） followed by Aeromonas spp. （33 isolates）, Flavobacterium spp. （31 isolates）, and Vibrio spp. （30 isolates）. Majority of the bacterial isolates were found sensitive to furazolidone （85.0%）, chloramphenicol （85.0%）, oxolinic acid （90.0%）, florfenicol （95.0%）, and flumequine （97.5%）. On the other hand, most of the bacterial isolates were resistant to oleandomycin （77.5%） and lincomycin （87.5%）. Nitrofurantoin and flumequine can be inhibited the growth of all of Vibrio spp. whereas all isolates of Edwardsiella spp. were found sensitive to florfenicol and flumequine. Multiple antibiotic resistance （MAR） index were in range of 0.30-0.40, indicating that bacterial isolates from cultured bullfrogs may have received high risk exposure to the tested antibiotics. In addition, 90-100% of the isolates were resistant to copper, cadmium, and chromium. These results provided insight information on tolerance level of bacterial isolates from cultured bullfrogs to 21 antibiotics as well as heavy metals.
