Search Results (13)

Antibiotics are present in the environment, primarily due to their release through wastewater treatment plants, agricultural practices, and improper disposal of unused medications. In the environment, these drugs can be bioaccumulated by organisms and transferred along the food chain. This is a problem when considering the consumption of fish meat. In the United States, legislation stipulates that the maximum residue limit for sulfadiazine (SDZ) should not exceed 100 μg kg⁻¹. Lambari fishes have potential economic importance in aquaculture, as they are relatively easy to breed and can be raised in small-scale operations. Finally, studying the biology and ecology of lambari could provide valuable information about freshwater ecosystems and their inhabitants. The current work aimed to measure the bioaccumulation and depletion of the antibiotic SDZ ¹⁴C in lambari (Astyanax bimaculatus). For this purpose, the tests were divided into two stages; seven days of exposure and seven days of depletion, where one fish was randomly selected and sampled every day. In the exposure phase, the fish were fed the medicated feed three times a day at a concentration of 2.5 mg·g⁻¹. The control fish were fed uncontaminated feed. For the depletion phase, the remaining lambari were transferred to clean tanks and fed uncontaminated feed three times a day. The fish samples were burned in the Oxidizer and the reading of radioactivity was performed in a liquid scintillation spectrometer. It is worth noting that on day 7 and day 14, the water in the aquariums was filtered through filter paper to collect the metabolic excrement. SDZ concentrations increased over the days and accumulation occurred in the fish, with day seven presenting the maximum accumulation value of 91.7 ng·g⁻¹ due to feeding uptake. After the depletion phase on day 13, the value found was 0.83 ng·g⁻¹. The bioconcentration factor calculated was 20 L·kg⁻¹. After the bioaccumulation period, the concentrations of SDZ in the water and excreta were 4.5 µg·L⁻¹ and 363.5 ng·g⁻¹, respectively. In the depletion period, the concentrations in the water and excreta were 0.01 µg·L⁻¹ and 5.96 ng·g⁻¹, respectively. These results imply that there was little SDZ bioaccumulation in the fish, but that it was distributed in larger amounts in the water. This is due to the physicochemical properties of the molecule with the low Log P value. Regarding the maximum residue limit, the value was below the established value. This study contributes to understanding SDZ dynamics in an aquatic species native to Brazil. Full article

Non-native aquatic plants can alter the physiochemical condition of habitats and can have negative ecological and economic impacts. Thus, understanding the characteristics of non-native aquatic plant species is important as a foundation for the conservation of biodiversity and environmental management. The yellow flag (Iris pseudacorus) is an emergent aquatic plant native to Africa, northwest Asia, and Europe that has been introduced through the aquarium trade to all continents except Antarctica. This species has recently been brought into China and it has established large and widespread naturalized populations causing serious ecological and environmental problems. Unfortunately, information about the yellow flag in China is very scarce. We summarize the introduction pathways, current distribution, and ecological impacts of the yellow flag through field surveys and a review of the literature. We hope that this study can provide useful information for researchers and wetland managers involved with non-native emergent plants in China and other regions. Full article

Marine resources such as marine invertebrates and mangrove plants favor the production of secondary metabolites that exhibit antifouling properties. These natural-derived compounds are considered environmentally friendly compared to synthetic compounds with similar activity and technological applications. The current study was conducted to determine the antifouling properties of Diadema setosum (DS) and Sonneratia lanceolata (SL) crude extracts and their incorporated paints, in addition to the identification of the metabolites involved. Both crude extracts were tested against Pseudomonas aeruginosa via a crystal violet assay, while the incorporated paints with 5% (SL5% and DS5%) and 10% (SL10% and DS10%) weight per volume (w/v) were tested in an aquarium and submerged in the seawater at Kemaman and Pulau Redang (Malaysia) for field testing. The identification of the bioactive compounds from the crude extracts was carried out using Liquid Chromatography-Mass Spectrometry (LC-MS). The results of the crystal violet assay showed that both of the crude extracts reduced the biofilm formed by Pseudomonas aeruginosa. The marine bacteria growths contained in natural seawater were inhibited the most by SL5%, followed by DS5%, DS10%, and SL10% in the aquarium testing. Based on the photographic observation, all of the paints incorporated with the crude extracts successfully reduced the settlement of fouling organisms compared to the blank paint, as lesser macroalgae were found growing on the SL5%, DS5%, and DS10%. The LC-MS results showed 3-Methyloxiranyl phosphonic acid; (2RS,3SR)-form from the SL crude extract, while the 8-Decene-1,3,5-triol, 3-Hydroxyundecanoic acid, and 1-O-(6-Deoxy-6-sulfoglucopyranosyl)glycerol; α-D-form, 3-Hexadecanoyl from the DS crude extract were involved in the antifouling properties. In conclusion, both crude extracts have the potential to be developed as antifouling agents. Full article

With a range of programs focused on local plant and insect conservation, the Cincinnati Zoo & Botanical Garden works with partners and our communities to restore landscapes and thriving ecosystems for wildlife and people. We used organizational identity theory (OIT) to evaluate the current strategies and practices of five programs and determine opportunities for adaptation to better achieve our organizational conservation goals. Case studies ranged from habitat restoration of wetlands and gardens to community engagement to encourage individual gardeners and the reintroduction of endangered plants and insects. We present program characteristics and how collaborative partnerships facilitate opportunities for zoos to lead the conservation of local flora and fauna. The OIT framework reveals components critical to strategy implementation and best practices relevant to other zoos, aquariums, and botanical gardens when evaluating their collaborative conservation initiatives. Full article

Effective conservation of endangered species relies on the characterization of habitat use and tracking of long-term population trends, which can be especially challenging for marine species that migrate long distances and utilize a diversity of habitats throughout their lives. Since 2012, citizen science volunteers at the Aquarium of the Pacific in Long Beach, California, have been monitoring an urban population of East Pacific green sea turtles (Chelonia mydas) that resides near the mouth of the San Gabriel River (SGR) in Southern California, USA, in order to gain insights about how the population uses this area. Here, we collate and analyze nine years of citizen science data, including observed sightings collected across 10 observation stations. Our results confirm that green sea turtles are frequently present around warm water effluent from power plants, similar to research results reported for other locations in the eastern Pacific Ocean. Importantly, observational data also show notable green sea turtle activity around the outfalls for a small wetland habitat bordering the SGR, highlighting the importance of wetland ecosystems as a key habitat and foraging area for this threatened population. Finally, our results showcase the benefits of using citizen science to monitor sea turtle populations in easily accessible nearshore habitats. Full article

Guizhou is one of the centers of origin for the tea plant (Camellia sinensis (L.) Kuntze). The location contains highly diverse ancient tea plant germplasms in its Sandu Aquarium Autonomous County. After a prolonged course of continuous evolution, these ancient plants have gained a wealth of genetic diversity. Their resources could be harnessed for the selection and breeding of fine varieties of tea plant, as well as for the effective utilization and protection of germplasm resources. In this study, the specific locus-amplified fragment (SLAF) sequencing method was used to analyze the population structure and conduct a genome-wide association study (GWAS) for the three traits of 125 ancient tea plants in the Sandu County of Guizhou province, China. A total of 807,743 SLAF tags and 9,428,309 population single-nucleotide polymorphism (SNP) tags were obtained. The results of the phylogenetic tree analysis, cluster analysis, and principal component analysis showed that 125 germplasms were clustered into four groups, and the heterozygosity rates for groups I, II, III, and IV, were 0.211, 0.504, 0.144, and 0.192, respectively. Additionally, GWAS analysis suggested that seven candidate genes were related to altitude at the origin of the plants, eight were related to tree shape, and three were associated with leaf color. In this study, we clarified genetic relationships between four ancient tea plant-producing areas in Sandu County and obtained candidate genes related to their development associated with altitude, tree shape, and leaf color. The study provides useful information for tea plant-breeding development and molecular identification. Full article

Anubias Schott (Araceae) have high ornamental properties as aquarium plants. However, the genus has difficulties in species identification, and the mechanism of its adaptation to the aquatic environment is unknown. To better identify species and understand the evolutionary history of Anubias, the plastomes of Anubias barteri Schott, A. barteri var. nana (Engl.) Crusio, and A. hastifolia Engl., were sequenced. The sizes of the plastomes of Anubias ranged from 169,841 bp to 170,037 bp. These plastomes were composed of conserved quadripartite circular structures and comprised 112 unique genes, including 78 protein-coding genes, 30 transfer RNA genes, and 4 ribosomal RNA genes. The comparative analysis of genome structure, repeat sequences, codon usage and RNA editing sites revealed high similarities among the Anubias plastomes, indicating the conservation of plastomes of Anubias. Three spacer regions with relatively high nucleotide diversity, trnL-CAA-ndhB, ycf1-ndhF, and rps15-ycf1, were found within the plastomes of Anubias. Phylogenetic analysis, based on 75 protein-coding genes, showed that Anubias was sister to Montrichardia arborescens (L.) Schott (BS = 99). In addition, four genes (ccsA, matK, ndhF, and ycf4) that contain sites undergoing positive selection were identified within the Anubias plastomes. These genes may play an important role in the adaptation of Anubias to the aquatic environment. The present study provides a valuable resource for further studies on species identification and the evolutionary history of Anubias. Full article

This study was carried out to evaluate combined and singular effects of ethanolic extract of Persian shallot (Allium hirtifolium Boiss) and synbiotic Biomin^®IMBO on growth performance, innate immune responses, and antioxidant defense in zebrafish (Danio rerio). Fish with initial weight of 151.90 ± 0.31 mg were allocated in 21 10-L glass aquariums. The experimental groups were as follows: T1, control (without any supplementation); T2, 1% synbiotic; T3, 3% synbiotic; T4, 1% Persian shallot (as a medical plant); T5, 3% Persian shallot; T6, 1% Persian shallot and 1% synbiotic; T7, 3% Persian shallot and 3% synbiotic. At the end of the experiment (60 days), all treatments significantly showed higher final weight (FW), weight gain (WG), WG (%), and specific growth rate (SGR) compared with the fish fed on control diet. Furthermore, both synbiotic Biomin^®IMBO and Persian shallot significantly improved intestine immune parameters including lysozyme, alternative complement hemolytic activity (ACH50), total immunoglobulin (total Ig), and myeloperoxidase (MPO) of zebrafish compared to fish fed on control diet (p < 0.05). Also, in all experimental groups, hepatic catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GR) activities significantly increased compared to the control group. Whereas, the highest MDA level was observed in the control group compared to the treatments (p < 0.05). Moreover, skin mucus immune parameters of zebrafish have been noticeably improved with synbiotic Biomin^®IMBO and Persian shallot compared to fish fed on the control diet (p < 0.05). The results indicate that synbiotic or Persian shallot supplemented diet could enhance the general health status of the zebrafish. Full article

The effects of two aquatic plants, duckweed (Lemna sp.) and azolla (Azolla sp.), on the growth performance of fantail goldfish (Carassius auratus) and dissolved nutrient concentrations were studied. The experiments were carried out in triplicate sets over a period of seven weeks. Eight specimens of fantail goldfish (length = 5.16 ± 0.06 cm; body weight = 2.30 ± 0.06 g) were released into each of the aquariums containing 40 L of water. Submerged sponge filters were used as the substrate (bed) for the nitrifying bacteria to facilitate nitrification. The fish were provided feed at the rate of 2% of their body weight twice daily. In situ and ex situ water parameters (temperature, dissolved oxygen, pH, total suspended solids, ammonia, nitrite, nitrate, and phosphate), body weight and length of the Fantail goldfish, and wet weight of aquatic plants were measured weekly. The results showed no significant differences (p > 0.05) in any of the three aquariums in water temperature, pH, and dissolved oxygen. Survival of the fish was 100%. The highest food conversion ratio and specific growth rate were observed in the aquarium stocked with duckweed, followed by the aquarium with azolla and the control set (p < 0.05). The concentrations of nutrients (ammonia and nitrate) were recorded lowest (p < 0.05) in the aquarium with azolla, followed by duckweed and the control. The results suggested that aquatic plants were effective in absorbing nutrients and can serve as biofilters to create better conditions for the growth of the fantail goldfish. Full article

Application of herbal immune-stimulants for modulation of fish growth and immune response has received great interest during the past decades. With several pharmacological properties, Doum palm, Hyphaene thebaica (Mart.) is known to be a beneficial medicinal plant. The objective of this study was to investigate the effects of the dietary addition of doum palm fruit powder (DPFP) on growth performance, non-specific immune response, and antioxidant parameters of African catfish, Clarias gariepinus (B.). A total of 120 fish (average initial weight 60.50 ± 0.04 g) were randomly allocated to four groups (three replicates/group, 10 fish/aquarium); a basal diet without DPFP supplementation was used as a control, and three other diets were prepared by supplementing 5, 10, or 15 g kg⁻¹ DPFP for a ten-week feeding period. Following ten weeks of feeding, the fish were challenged with Aeromonas hydrophila (as an immune challenge test), and mortalities were recorded. In comparison to the control diet, dietary DPFP significantly improved growth parameters, including final body weight, body weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR), and protein efficiency ratio (PER), along with an increase in the content of dry matter of the whole body, in a concentration-dependent manner. Moreover, the heights of intestinal villi, numbers of goblet cells, and intraepithelial lymphocytes (IEL) exhibited marked escalation in all parts of the intestine by increasing the level of DPFP, except for numbers of IEL in the proximal part. The decline in serum glucose, cholesterol, and triglyceride levels was prominent in DPFP10 and DPFP15 groups respective to the DPFP0 group. Furthermore, DPFP boosted the hepatic level of catalase (CAT) in the fish, in a dose-dependent manner; meanwhile, the activity of superoxide dismutase (SOD) and reduced glutathione (GSH) content were also augmented in DPFP10 and DPFP15 groups respective to the DPFP0 group. Dietary DPFP (DPFP15 followed by DPFP10 then DPFP5) led to a pronounced enhancement in the innate immune response (phagocytic percent and index, lysozyme activity, nitric oxide (NO) production, and sialoglycans, namely α 2,3-sialyltransferase and α 2,6-sialyltransferase content); however, the myeloperoxidase (MPO) activity was reduced. Significantly higher relative percentage survival (RPS, 88.56%) of the fish, following the A. hydrophila challenge, was observed for the DPFP15 group. We can suggest that DPFP can beneficially influence fish growth, intestinal histomorphology, hepatic levels of catalase (CAT), superoxide dismutase (SOD) activity and glutathione (GSH) content, immune response, and disease resistance against A. hydrophila challenge. Full article

Increased salinity caused by saltwater intrusion or runoff from de-icing salts can severely affect freshwater vegetation and deteriorate aquatic ecosystems. These habitats can be restored with freshwater ecotypes (locally adapted populations) that tolerate above-normal salinity. Vallisneria americana is a prominent species in many freshwater ecosystems that responds differently to abiotic conditions such as substrate composition and fertility, so, in this study, we evaluated the effects of salt stress on 24 ecotypes of V. americana. Instant Ocean aquarium salt was used to create saline solutions (0.2 to 20.0 parts per thousand (ppt)), then plants were abruptly exposed to these solutions and maintained in these concentrations for five weeks before being visually assessed for quality and destructively harvested. Analysis of variance and nonlinear regression were used to calculate LC₅₀ values—the lethal concentration of salt that reduced plant biomass and quality by 50% compared to control treatment. Growth rate and visual quality varied significantly among ecotypes, and ecotypes that were most and least sensitive to salt had 50% biomass reductions at 0.47 and 9.10 ppt, respectively. All ecotypes survived 10.0 ppt salinity concentration but none survived at 20.0 ppt, which suggests that the maximum salinity concentration tolerated by these ecotypes is between 15.0 and 20.0 ppt. Full article

Bacopa caroliniana (BC) is a perennial creeping herb and popular aquarium plant. This plant is easily cultivated; consequently, it has the potential to be a raw material which is readily available for mass production if it contains useful bioactive substances. The information about the functionality of this plant has been very limited. Therefore, the aims of this research were to analyze the composition of the essential oil (EO) of BC and to study its insecticidal effect on rice weevils. Moreover, the interactive effects of active compounds of the EO on this activity were also investigated. A total of 18 volatile compounds was identified, accounting for ca. 94% of the BC-EO in terms of quantity. Of them, α-terpinolene was the largest compound. The impact of individual volatile compounds on the inhibition of acetylcholine esterase and insecticidal activity were determined. α-Terpinolene exhibited the highest activity on these assays. Both additive and synergistic effects existed in terms of the insecticidal activity. Many compounds found in the BC-EO are widely present in other EOs. Thus, the information obtained from this study is useful for EO-related research, applications in selecting EOs or in seeking the best combination of EOs or individual compounds to achieve efficient insecticidal effects. Full article

Plant proteins substitutes of fishmeal in aquafeed are usually lacking in some essential amino acids and fatty acids. The microalgae Chlorella vulgaris has good-quality protein with amino acids rich in methionine, lysine and alanine. Four novel diets having C. vulgaris as the main source of protein were produced for African catfish Clarias gariepinus with an initial average weight of 1.09 ± 0.05 g. The diets were labeled Feed 1 (F1) to feed 4 (F4). The treatment diets were included 25% (F1), 15% (F2), 5% (F3) and 0% (F4) green algae meal. The basal ingredients of the feed were corn (maize) included as F1, 40%, F2, 43%, F3, 53% and F4, 43%; and millet meal, which varied in F1 as 23%, F2, 30%, F3, 30% and F4, 30%. The ingredients were preconditioned at 110 °C and pelleted. Post-fingerling African catfish were stocked at 10 fish per aquarium. There were three replicate aquariums for each feed type and the fish were fed for 60 d. The specific growth rate was best for the catfish fed with 25% C. vulgaris diet 7.86 ± 0% day⁻¹, and worst at 6.77 ± 0.07% day⁻¹ for the control group F4, 0% algal meal. The food conversion ratio (FCR) was lowest (1.88 ± 0.02) for 25% algal meal diet (F1) and highest (2.98 ± 0.01) for the 0% algal meal diet F4. Similarly, catfish had average weight gain of 121.02 ± 0.04 g for those fed with F1 compared to 62.50 ± 0.0 g for those fed with 0% algae F4. Protein efficiency ratio was highest for the F1-fed fish (2.46 ± 0.22) and lowest for those fed with F4 (2.02 ± 0.09). The hepatosomatic index was lowest for F1-fed fish (1.48 ± 0.01) and highest for catfish fed with F4 (2.50 ± 0.59). Based on the results, C. vulgaris is a good protein source for African catfish and can also substitute fishmeal in the catfish diets. Full article