Explanation of the purpose and objectives of the study (2-3 lines). Mangrove ecosystems perform biological and socioeconomic functions. Mangrove environments can be ecotourism destinations. This ...study analyzes mangrove potential to determine typical mangrove ecotourism attractions and strengthen the branding and marketing of mangrove ecotourism destination on the Tamban coast of Malang Regency, Indonesia. Explanation of the working methodology and the materials used (2-3 lines). Local management and communities validate mangrove potential field observations. GIS with Sentinel-2 and NDVI approach was used to analyze tides and satellite imaging data on mangrove thickness, density, and area. Analysis of mangrove potential in ArcMap utilizing five parameters: thickness, density, kind, biota, and tides. Four density classes were created using satellite imagery: non-mangroves, rare mangroves, moderate mangroves, and tight mangroves. Presentation and analysis of the obtained results (2-4 lines). The results showed that the Tamban coast mangrove area has a moderate ecotourism potential (potential value = 2.250), so it could be developed into mangrove ecotourism through conservation and limited utilization activities through marine ecotourism to provide economic, ecological, and social incentives. Mangrove ecotourism features that attract tourists and strengthen branding and marketing of this location include mangrove tourism education, canoeing, camping, spot photography, beach attractiveness, bird and violin crab biodiversity. The conclusions obtained following the application of the study (2-3 lines). Mangrove ecosystem on the Tamban coast has a high potential for conservation and marine ecotourism in order to provide economic incentives, also ecological and social benefits. The richness and distinctiveness of Tamban's mangrove ecotourism potential and attractions promotes the GPMC branding as a typical mangrove ecotourism.
Aim: The aim of the present study was to analyze two different culture systems for their suitability in rearing the Genetically Improved Farmed Tilapia fry. Methodology: Genetically Improved Farmed ...Tilapia fry (Average body weight 0.50 g) were stocked, at a rate of 1500 fry,in tank and hapa.Three cement tanks (2 m × 2 m × 1 m; 4000 l) and three nursery hapa (2 m × 2 m × 1 m) were used for this experiment following completely randomized design. Fry were fed using prepared diet (crude protein 32%) at a feeding rate of 8-10 % of their body weight for 45 days. Fortnightly, feeding rate was adjusted based on the sampling. Results: After 45 days of rearing, tilapia fry attained a body weight of 5.44 g and 7.47±0.00 g in cement tanks and hapa based production systems, respectively. The specific growth rate significantly differed and it was higher (5.98 %/day) in hapa based system. Similarly, survival was significantly higher (92.00 %) in hapa based system. In contrast, increased feed conversion ratio was noticed in tank-based culture system (2.06) than the hapa based system (1.69). The protein efficiency ratio was significantly higher (1.97) in hapa based system. The recorded water quality parameters were within the optimal range for rearing of Genetically Improved Farmed Tilapia fry. Interpretation: Overall, the results of this study demonstrated that rearing of Genetically Improved Farmed tilapia fry in hapa, installed in earthen pond, would lead to better growth, feed utilization and survival. This method can be disseminated to farmers for better profitability in seed production of Genetically Improved Farmed Tilapia.
The genus
, an important group of catfish, exhibits heterogeneous distribution in Eurasian freshwater systems. This group includes economically important and endangered species, thereby attracting ...considerable scientific interest. Despite this interest, the lack of a comprehensive phylogenetic framework impedes our understanding of the mechanisms underlying the extensive diversity found within this genus. Herein, we analyzed 89 newly sequenced and 20 previously published mitochondrial genomes (mitogenomes) from 13 morphological species to reconstruct the phylogenetic relationships, biogeographic history, and species diversity of
. Our phylogenetic reconstructions identified eight clades, supported by both maximum-likelihood and Bayesian inference. Sequence-based species delimitation analyses yielded multiple molecular operational taxonomic units (MOTUs) in several taxa, including the
complex (four MOTUs) and
(two MOTUs), suggesting that species diversity is underestimated in the genus. A reconstructed time-calibrated tree of
species provided an age estimate of the most recent common ancestor of approximately 37.61 million years ago (Ma), with divergences among clades within the genus occurring between 11.56 Ma and 29.44 Ma, and divergences among MOTUs within species occurring between 3.71 Ma and 11.56 Ma. Biogeographic reconstructions suggested that the ancestral area for the genus likely encompassed China and the Korean Peninsula, with multiple inferred dispersal events to Europe and Central and Western Asia between 21.78 Ma and 26.67 Ma and to Japan between 2.51 Ma and 18.42 Ma. Key factors such as the Eocene-Oligocene extinction event, onset and intensification of the monsoon system, and glacial cycles associated with sea-level fluctuations have likely played significant roles in shaping the evolutionary history of the genus
.
Aim: The study aimed to investigate the morphometric and meristic measurements, length-weight relationship and relative condition factor of Odonus niger landed along coastal Karnataka. Methodology: ...The morphometric and meristic measurements, length-weight relationship and relative condition factor (Kn) of O. niger was studied for a period of eight months from August 2019 to March 2020. The different morphometric characters were subjected to statistical analysis. The length-weight relationship was analyzed for both the sexes (female and male) and combined data. Monthly relative condition factor was analyzed for both the sexes and for different size group. Results: A comparison of different morphometric measurements exhibited good extent of correlation indicating good extent of interdependence of these characters. Four out of eight morphometric characters are environmentally controlled and suggested wide range of zoogeographical distribution of O. niger. The length-weight relationship is indicated as W = 0.046 L2.565, W = 0.044 L2.589 and W = 0.047 L2.561 with coefficient of determination (r2) of 0.910, 0.913 and 0.910 for male, female and combined sexes, respectively. The 'b' values of both the sexes (male and female) exhibited negative allometric growth (p<0.05) and appeared to be leaner. There was no significant (p<0.05) variation for relative condition factor (Kn) among the months and size groups. However, little higher values were observed during November and February. Interpretation: The study fills the knowledge gap and support for developing a suitable management system for this fish species.
Aim : Schizothorax labiatus is one of the economically valuable food fish among indigenous schizothoracids (snow trouts), inhabiting the Jhelum River system in Kashmir along with other snow trouts of ...family Cyprinidae. The present study was conducted to understand and bring forward various reproductive traits of S. labiatus inhabiting River Jhelum. Methodology : The investigation was carried on 310 samples (221 males and 89 females) with total length and total weight ranging between 143 to 350 mm and 62 to 449 g, respectively, for a period twelve months. Results : Gonadosomatic index (GSI) was recorded maximum during April for both males (6.19) and females (11.12), indicating that the fish fully matures during this month and spawns during coming months i.e, May when the GSI values start decreasing abruptly. The average values of absolute and relative fecundity in the fish were recorded per gm body weight as 10323 and 42, respectively. Sex ratio was found in 1:0.41 ratio, indicating a significant dominance of males over opposite sex and Lm, i.e., length at first maturity was estimated to be 196 mm and the corresponding age at this length was 2+years. Interpretation : The fish breeds once in a year in natural/wild habitat. These findings on reproductive biology of the endemic snow trout, and the influence of environmental conditions on breeding biology will serve as a baseline data towards planning seed production and conservation strategies.
We re-analyze Thorny skate data from two comparative fishing experiments conducted by DFO in 1995 and 1996 using improved and more contemporary methods to estimate the relative efficiency of the ...Campelen 1800 demersal shrimp trawl survey protocol compared to the Engel 145 otter trawl. We correct possible bias in the method previously applied to these data. We investigate if there are size-based differences and if depth or spatial regions have important effects on results. We also investigate the influence and robustness of the estimation procedures, which was a concern in the original analyses of these data for other groundfish species. We did not find strong evidence that the relative efficiency of the Campelen trawl protocol compared to the Engel was different for smaller-sized Thorny skate compared to larger ones. However, we conclude that there is a potential that size-based differential catchability existed but there is insufficient information to reliably estimate these effects for Thorny skate. We also found evidence of significant differences in relative efficiency among NAFO Divisions and experiments, which is similar to other flatfish species. However, the mechanisms for these differences are unknown and it is not clear if spatial estimates should be used when converting Engel indices to Campelen equivalents. Hence, we do not recommend a different Engel-Campelen conversion factor than the one currently used in stock assessments for Thorny skates on the Grand Banks (NAFO Divisions 3LNOPs).
Aim: Landmark-based truss network system was applied to examine the morphometric and meristic differences among four different populaces of Macrognathus aculeatus namely; Dhakuriabeel, Jashore (DBJ); ...Arial Kha River, Madaripur (AKRM); Nabaganga River, Jhenaidah (NRJ); Kopotakkha River, Jashore (KRJ) in Bangladesh. Methodology: Completely 80 samples of M. aculeatus were collected (20 individuals from each population) for this study. Six meristic characters, 6 morphometric characters and 15 truss-based morphometric characters were measured for one-way analysis of variance (ANOVA) and Tukey-HSD post hoc test. Discriminant function analyses were also performed by using morphometric and truss-based morphometric characters to detect potential characters responsible for population separation. Results: Completely 80 samples of M. aculeatus were collected (20 individuals from each population) for this study. Six meristic characters, 6 morphometric characters and 15 truss-based morphometric characters were measured for one-way analysis of variance (ANOVA) and Tukey-HSD post hoc test. Discriminant function analyses were also performed by using morphometric and truss-based morphometric characters to detect potential characters responsible for population separation. Interpretation: The baseline information derived from the present study would be useful for appropriate conservation of M. aculeatus populations as well as for the researchers for further investigation.
Prevalence of brucellosis in ruminants in Bangladesh Rahman, M.S.,Bangladesh Agricultural Univ., Mymensingh (Bangladesh); Faruk, M.O.,Bangladesh Agricultural Univ., Mymensingh (Bangladesh); Her, M.,Ministry of Food, Agriculture, Forestry and Fisheries, Anyang (Republic of Korea). Animal, Plant and Fisheries Quarantine and Inspection Agency ...
Veterinární medicína,
08/2011, Letnik:
56, Številka:
8
Journal Article
Recenzirano
Odprti dostop
The prevalence of brucellosis was determined in buffaloes, cattle, sheep and goats in the districts Bagerhat, Bogra, Gaibangha, Mymensingh and Sirajgonj in Bangladesh. A total of 550 sera samples ...(105 buffaloes, 188 cattle, 127 goats and 130 sheep) were screened by RBT and were further confirmed with I-ELISA. A structured questionnaire was used to collect epidemiological information. The overall serological prevalence derived from the samples was 2.87% in buffaloes, 2.66% in cattle, 3.15% in goats, and 2.31% in sheep. The prevalence was relatively higher in females than in males in cattle, goats and sheep, but an insignificantly higher prevalence was observed in buffalo males than buffalo females. A significant association was found between abortion or age and occurrence of brucellosis. Our results provide (a) a comparison of the prevalence of brucellosis in different livestock species in Bangladesh, (b) constitute baseline data for further study of Brucella infections, and (c) are a starting point for the control of brucellosis.
Increases in natural mortality have been suggested as a potential driver for both the collapse and lack of recovery for the American plaice (Hippoglossoides platessoides) population on the Grand Bank ...of Newfoundland in NAFO Divisions 3LNO. However, natural mortality is among the most difficult parameters to estimate since it can be confounded with other parameters and model misspecifications. One method used to avoid this confounding involves modeling unfished components of a population where total mortality and natural mortality are equal. Here, we use a state-space metapopulation dynamics model to investigate whether there is evidence that natural mortality rates for unfished juvenile American plaice have varied since the population collapse. In addition, our model examined the degree of synchrony in age-1 recruitment signals between each management Division. The best fitting model included temporal variability in natural mortality rates, but estimates did not frequently differ from zero. This indicates that change in natural mortality rates is not an important driver of current juvenile 3LNO American plaice stock dynamics. Instead, this model identified that juvenile stock dynamics were mainly affected by variations in age-1 recruitment. Furthermore, a correlation analysis of the temporal variations in recruitment showed that trends were somewhat dissimilar between NAFO Divisions 3L and 3NO. Overall, although increases in M have been suggested by recent studies, we did not find strong evidence for this in juvenile fish.
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