Apple Snail Pomacea Canaliculata Research Articles

福寿螺和田螺的消化酶活性比较研究

福寿螺和田螺的消化酶活性比较研究

Modeling behavior control of golden apple snails at different temperatures

The golden apple snail (Pomacea canaliculata) is a detrimental invasive pest of rice in Asia. Temperature is a critical factor to determine their invasiveness including the behavior and distribution of snails. In this study, the behavioral responses of golden apple snails acclimated to different water temperatures (15°C, 20°C, 25°C, and 30°C) were examined based on Markov chain analysis, Shannon entropy, and Random forest modeling. Markov chains revealed that most snails maintained their previous behavior at low temperatures, while behavior transition tended to be higher at high temperature. Shannon entropy was also dependent on temperature (low at low temperature and high at high temperature), indicating that snails maintained their previous behavior for a long time at low temperature regardless having motion and motionless behavior, whereas they changed continuously their behavioral types at high temperature. The Random forest model showed that Shannon entropy at low temperature was influenced by crawling at the bottom or at side of the aquarium (motion behavior), while clinging to the side of the aquarium or clinging to the side of the aquarium with stretching out antennae were important behaviors determining Shannon entropy at high temperature. Our results showed that snails controlled their behavior to reduce their thermal stress and maintain a stable internal state in harsh environment. With this mechanism, they are able to overwinter in the open fields with low temperature in Korea, resulting in the increase of potential damage in agricultural ecosystems. Therefore, further study on the development of adequate management system is required to avoid their invasiveness to open water systems and ecological impacts. Finally, Shannon entropy, Markov chain, and Random forest model are useful computation methods to quantify the effects of temperature changes on the behavior of golden apple snails.

Astaxanthin extraction from golden apple snail (Pomacea canaliculata) eggs to enhance colours in fancy carp (Cyprinus carpio)

High-value ornamental fish farming is one of the most valuable industries in the recent years, and the commercial value of ornamental fish, such as fancy carp (Cyprinus carpio) is primarily dependent on their body coloration. Therefore, a trial was conducted to investigate skin colour enhancement in fancy carp by feeding different levels (0, 25, 50, 100 and 200 mg/kg) of a dietary natural astaxanthin extracted from golden apple snail (Pomacea canaliculata) eggs, using a diet containing synthetic astaxanthin (50 mg/kg) and a control diet with no colouring added for comparison. The duration of the trial was four weeks with experimental diets containing carotenoid followed by the low carotenoid diet for other two weeks. The chromaticity of fish body skin of red and white position was assessed using the CIE L* a* b* system. Pigmentation response of skin redness (a*) of fancy carp fed with diets at 50, 100 and 200 mg/kg of natural astaxanthin supplement was higher than other treatments (P < 0.05). The lightness and yellowness (L* and b* values) indexes of carp fed with diet containing astaxanthin from golden apple snail eggs were similar compared to the other dietary treatments (P > 0.05). After two weeks of feeding diet without natural carotenoid supplement demonstrated that the group fed 50 mg/kg of natural astaxanthin still retained their redness (a*) and also had an overall tendency to improve skin colouring (L* and b*). Finally, dietary concentrations 50 mg/kg of astaxanthin extracted from golden apple snail eggs showed the highest efficiency for improving skin pigmentation in fancy carp.

Antipredator behaviour in response to single or combined predator cues in the apple snail Pomacea canaliculata

The documentation of antipredator behaviour associated with different risk levels (threat-sensitive predator avoidance), different predators (predator-specific avoidance) or combined predators (multiple predator avoidance) in freshwater caenogastropods is limited. We studied the antipredator behaviour of predator-naive hatchlings of the invasive apple snail Pomacea canaliculata to chemical cues from the common carp (Cyprinus carpio), Reeve's turtle (Mauremys reevesii) and crushed conspecifics in three laboratory experiments. First, we tested the snails' responses of crawling out of the water and self-burial in the sand to odour from a single nonfeeding predator or crushed conspecifics. A greater proportion of snails responded to odour from crushed conspecifics than to turtle or carp odours. Second, we studied the snails' responses to cues simulating a single feeding predator. When combined with cues from crushed conspecifics, snails tended to bury themselves in the sand in response to the turtle odour whereas they tended to crawl above the waterline in response to the carp odour. Third, we compared the snails' responses to single or combined predator cues. In the presence of cues from crushed conspecifics, the snails' responses to the combined odours from turtle and carp were more similar to the responses associated with the carp odour than to those associated with the turtle odour. Overall, these experiments indicate that P. canaliculata hatchlings show fine-tuned innate antipredator behaviour.

Use of Apple Snails (Pomacea canaliculata) as a Source of Fatty Acids in Feed Towards the Performance, Blood Cholesterol and Cholesterol Levels in Alabio Duck (Anas platyrhinchos borneo) Meat and Eggs

Use of Apple Snails (Pomacea canaliculata) as a Source of Fatty Acids in Feed Towards the Performance, Blood Cholesterol and Cholesterol Levels in Alabio Duck (Anas platyrhinchos borneo) Meat and Eggs

Uric acid-degrading bacteria in the gut of the invading apple snail Pomacea canaliculata and their possible symbiotic significance

In previous studies we have mapped uric acid deposits in specialized tissues of the invading apple snail Pomacea canaliculata. Uric acid stores function as reservoirs of combined nitrogen in insects. The first step for recycling uric acid nitrogen involves the action of uricase and here we explored the occurrence of uricase-positive bacteria in the gut of this snail. Six bacterial strains assigned to the genera Pseudomonas, Enterobacter, Citrobacter and Lactococcus were isolated on the basis of their ability to grow in vitro in a medium containing uric acid as the only carbon and nitrogen source. Uricase specific activity could be determined in three of these genera (not in Citrobacter), showing optimal pH values ranging 7.3–8.7 and optimal substrate concentrations (ranging 25–30 μM). These uricolytic bacteria may participate in recycling of combined nitrogen in this snail.

Impacts of golden apple snail (Pomacea canaliculata) on water quality and microbes

Impacts of golden apple snail (Pomacea canaliculata) on water quality and microbes

Canal type affects invasiveness of the apple snail Pomacea canaliculata through its effects on animal species richness and waterweed invasion

Loss of complex natural microhabitats due to human activity is a major cause of decreased biodiversity but its effects on biological invasion are not well understood. The effects of physical environmental factors, especially the type of agricultural canals, on the invasive freshwater snail Pomacea canaliculata were studied at 33 sites in the Chikugogawa River basin, Kyushu, Japan. Differences among sites in the local fauna and vegetation were also monitored. Structural equation modeling with a model selection procedure revealed that canals with a concrete lining had more snails. The effect was indirect in that the concrete lining reduced animal species richness and increased the invasive waterweed Egeria densa, which may serve as a refuge, protecting the snails from predation. A tethering experiment conducted simultaneously indicated high predation pressure on the snails: over 20 % of the tethered snails were lost within a day. Thus, human impacts may increase biological invasion by reducing biotic resistance and increasing the risk of invasional meltdown.

Invasive apple snails (Pomacea canaliculata) are predators of amphibians in South China

Invasive species are one of the most serious threats to amphibian populations. We investigated the effects of two invasive (Pomacea canaliculata and Physella acuta) and one native (Radix sp.) snail species on five species of wetland-breeding frogs in Hong Kong. We quantified embryonic survivorship and determined whether particular attributes of amphibian egg masses influenced consumption by snails. P. canaliculata preyed on four of the species, consuming >90 % of eggs of Microhyla fissipes and Fejervarya limnocharis, nearly 70 % of eggs of Kaloula pulchra, approximately 40 % of eggs of Duttaphrynus melanostictus, but no eggs of Polypedates megacephalus. P. acuta and Radix sp. consumed only the eggs of K. pulchra, but those eggs were probably non-viable. This study shows that P. canaliculata, which occurs at high densities in tropical East Asia, may be an important predator of amphibian eggs. Future research should evaluate their effects on amphibian populations, community structure, and food web dynamics.

Integrated Management to Control Golden Apple Snails (Pomacea canaliculata) in Direct Seeding Rice Fields: An Approach Combining Water Management and Rice-Duck Farming

Direct seeding has high potential to reduce water and labor use. However, the extension of conventional direct seeding is facing great golden apple snail pest problems. To establish an agrochemical-free management for reducing damage, an integrated approach combining rice-duck farming system and water management was developed. Results showed that dry direct seeding was effective in reducing seedling loss at the beginning of rice growth, and the following duck herding significantly reduced the snail populations in the flooding period. With increasing shortage of water and labor force, this integrated approach might have great potential for controlling snails, especially for water-deficient areas in Asia.

Biological control of invasive apple snails by two species of carp: Effects on non-target species matter

Molluscivorous fish, especially carp, have been adopted as bio-control agents of the invasive apple snail Pomacea canaliculata, but previous studies have focused on their effectiveness, with little attention paid to their undesirable effects on non-target plants and animals. We conducted an 8-week mesocosm study to compare the effectiveness of two indigenous fish, common carp (Cyprinus carpio) and black carp (Mylopharyngodon piceus), in removing P. canaliculata, and their potential side effects on macrophytes and non-target mollusks in a freshwater wetland. Three species of macrophytes and a community of mollusks in the wetland sediment were enclosed in 1×1×1m enclosures either with apple snails (AS), with apple snails and common carp (AS+CC), with apple snails and black carp (AS+BC), or without apple snails and fish. Both species of carp were effective predators of P. canaliculata, removing most of the individuals in the enclosures except a few that were too big to fit into their mouth. By reducing apple snail population, black carp reduced grazing of apple snail on macrophytes. In contrast, although common carp controlled apple snail population, it did not reduce overall loss in plant biomass as the fish might also fed on macrophytes. Both species of carp preyed on non-target mollusks. Application of bio-control agents in invasive species management needs to consider their effects on both the pest and non-target plants and animals. Adoption of common and/or black carp to control apple snail populations thus depends on the weight given to their effectiveness and subtle different effects on non-target organisms by wetland management authority.

The potential ecological impact of the exotic snail Pomacea canaliculata on the Thai native snail Pila scutata

ABSTRACT: The aims of this study were to compare food consumption, growth rates, time to reach food, and food preferences of the golden apple snail (Pomacea canaliculata) and the Thai native snail (Pila scutata). The eggs of the two species collected from natural habitats were hatched in the laboratory. Snails of one month were raised together and separately to determine growth rates and food consumption. It was found that the growth rate of P. canaliculata was significantly faster than that of P. scutata when both were raised together and when they were raised separately. Both snails grew better when raised separately. P. canaliculata consumed significantly more food than P. scutata. When raised separately, P. canaliculata crawled to food at a significantly faster rate than P. scutata. On average, P. canaliculata and P. scutata took 8.2± 3.2 and 15.1± 3.1 min, respectively, to reach the food offered. To test for food preferences, four local species of aquatic plants, namely Hydrilla verticillata, Nymphaea lotus, Salvinia cucullata, and Alternanthera triandra were provided to both snails. It was discovered that P. canaliculata consumed all the four different food species offered. In contrast, P. scutata tended to feed on S. cucullata rather than the other species. It is concluded that P. canaliculata was superior to P. scutata in terms of growth rates, food consumption, and was also non-selective for food and therefore there is no doubt that in a shared habitat, P. canaliculata will influence P. scutata.

Molecular characteristics of the HSP70 gene and its differential expression in female and male golden apple snails (Pomacea canaliculata) under temperature stimulation

Heat-shock protein 70 (HSP70) is one of the most important heat-shock proteins that helps organisms to modulate stress response via over-expression. The HSP70 gene from Pomacea canaliculata was cloned using the RACE approach; the gene is 2,767bp in length and contains an open reading frame of 1,932bp, which is encoded by a polypeptide of 643 amino acids. BLAST analysis showed that the predicted amino acid sequence of the P. canaliculata HSP70 gene shared a relatively high similarity with that of other known eukaryotic species that display conserved HSP characteristics. The phylogeny demonstrated a separate clustering of the apple snail HSP70 with other constitutive members from other mollusk species. Quantitative real-time RT-PCR was used to detect the differential expression of HSP70 in both sexes of P. canaliculata at different temperature conditions. These results showed that HSP70 transcript levels decreased slightly under cold shock and increased significantly under heat-shock conditions in both sexes compared to normal temperatures (26°C). Under cold-shock treatment, the sex effect was not significant. With heat treatment, HSP70 expression could be induced at 36°C in both females and males, and it peaked at 42 and 39°C in females and males, respectively. In addition, a clear time-dependent HSP70 expression pattern of the apple snail exposed to the same high temperature (36°C) was observed at different time points. The maximal induction of HSP70 expression appeared at 12 and 48h in males and females after heat shock, respectively. The maximal induction in females was significantly higher compared to males under heat stimulus. Taken together, these results strongly suggested that males were more susceptible to heat than females and provided useful molecular information for the ecological adaptability of P. canaliculata against extreme environmental stress.

Characterizations of Cholinesterases in Golden Apple Snail (Pomacea canaliculata)

Cholinesterases (ChEs) have been identified in vertebrates and invertebrates. Inhibition of ChE activity in invertebrates, such as bivalve molluscs, has been used to evaluate the exposure of organophosphates, carbamate pesticides, and heavy metals in the marine system. The golden apple snail (Pomacea canaliculata) is considered as one of the worst invasive alien species harmful to rice and other crops. The ChE(s) in this animal, which has been found recently, but poorly characterized thus far, could serve as biomarker(s) for environmental surveillance as well as a potential target for the pest control. In this study, the tissue distribution, substrate preference, sensitivity to ChE inhibitors, and molecular species of ChEs in P. canaliculata were investigated. It was found that the activities of both AChE and BChE were present in all test tissues. The intestine had the most abundant ChE activities. Both enzymes had fair activities in the head, kidney, and gills. The BChE activity was more sensitive to tetra-isopropylpyrophosphoramide (iso-OMPA) than the AChE. Only one BChE molecular species, 5.8S, was found in the intestine and head, whereas two AChE species, 5.8S and 11.6S, were found there. We propose that intestine ChEs of this snail may be potential biomarkers for manipulating pollutions.

Understanding the Regulation of Estivation in a Freshwater Snail through iTRAQ-Based Comparative Proteomics

The apple snail Pomacea canaliculata is a freshwater gastropod with a remarkable ability to withstand seasonal or unpredictable dry conditions by entering estivation. Studies of P. canaliculata using conventional biochemical and the individual gene approaches have revealed the expressional changes of several enzymes and antioxidative genes in response to estivation and arousal. In this study, we applied iTRAQ-coupled two-dimensional LC-MS/MS to identify and quantify the global protein expression during the estivation and arousal of P. canaliculata. A total of 1040 proteins were identified, among which 701 proteins were quantified and compared across four treatments (i.e., control, active snails; short-term estivation, 3 days of exposure to air; prolonged estivation, 30 days of exposure to air; and arousal, 6 h after resubmergence in water) revealing 53 differentially expressed proteins. A comparison of protein expression profiles across treatments indicated that the proteome of this species was very insensitive to initial estivation, with only 9 proteins differentially expressed as compared with the control. Among the 9 proteins, the up-regulations of two immune related proteins indicated the initial immune response to the detection of stress cues. Prolonged estivation resulted in many more differentially expressed proteins (47 compared with short-term estivation treatment), among which 16 were down-regulated and 31 were up-regulated. These differentially expressed proteins have provided the first global picture of a shift in energy usage from glucose to lipid, prevention of protein degradation and elevation of oxidative defense, and production of purine for uric acid production to remove toxic ammonia during prolonged estivation in a freshwater snail. From prolonged estivation to arousal, only 6 proteins changed their expression level, indicating that access to water and food alone is not a necessary condition to reactivate whole-sale protein expression. A comparison with hibernation and diapause revealed many similar molecular mechanisms of hypometabolic regulation across the animal kingdom.

Should apple snail Pomacea canaliculata (Caenogastropoda, Ampullariidae) be used as bioindicator for BDE-209?

Apple snail Pomacea canaliculata has been reported to accumulate polybrominated diphenyl ethers (PBDEs) and was recently proposed as PBDE bioindicator. This work investigates the ability of P. canaliculata to accumulate BDE-209 by dietary exposure under controlled experimental conditions. A 30-day long enrichment feeding assay was carried out using 30 adult apple snails, placed in individual aquaria. Food was enriched at three BDE-209 concentrations (400, 4,700, and 8,300 μg g(−1) lipid weight). Correlation between BDE-209 values in food and snail tissue were estimated according to Stockholm Convention suggested criteria for chemicals with K(OW) >5. All animals survived with no evident physical alterations, and all of them accumulated BDE-209. BDE-209 levels in tissue samples increased exponentially with the exposure concentration. The bioaccumulation factor vs. food concentration plot showed a peculiar pattern, in which at intermediate concentrations the snails accumulated less BDE-209 than expected. Our results suggest that P. canaliculata would present a detoxification mechanism for BDE-209 different from the most commonly reported metabolic pathways.

Juvenile growth and survival of the apple snail Pomacea canaliculata (Caenogastropoda: Ampullariidae) reared at different constant temperatures

BackgroundPomacea canaliculata is a freshwater snail that cultured under certain conditions could provide interesting rewards in research and aquaculture. P. canaliculata is usually reared at 25°C, though the optimal temperature for culturing this species, that balances growth and survival rates, is so far unknown. In this work we present results of growth and survival of cohorts reared in the laboratory at different constant water temperatures (15, 20, 25, 30 and 35°C) during the pre-reproductive period.FindingsTwo different groups were recognized among the five treatments: the two lower temperatures (15 and 20°C) that showed no mortality but with very low growth rates and the treatments of 25, 30 and 35°C in which snails grew faster but displayed a reduction in survival as temperature increases. After 10 weeks, the mean shell lengths attained at 30 and 35°C were only 2–3 mm higher than that of the treatment of 25°C and were not statistically different.ConclusionsOur results support using water temperatures of 25°C for the rearing of cohorts when the objective is to quickly obtain numerous large snails. Temperatures of 15 and 20°C may be appropriate if the aim is to preserve juveniles for long periods with a very low risk of mortality. The results reported here will be useful to the scheduling of laboratory trials intended for basic research, snail control or mass rearing for different applications of this species.

Primer registro del caracol manzano exótico Pomacea canaliculata (Gastropoda: Ampullariidae) en México, con comentarios sobre su propagación en el bajo río Colorado

The apple snail Pomacea canaliculata (Lamarck, 1822) is for the first time reported for Mexico. The species was discovered in several locations adjacent to the Matamoros-1950 dam, Algodones, Baja California. The spread of P. canaliculata in Mexican waters was through the tributaries of the Colorado River from a population originally introduced in Yuma, Arizona, USA, around 2005. To date, no harmful effects have been detected on native vegetation, fauna of the Colorado River or agricultural crops in the Mexicali Valley, Baja California.

Reproductive organogenesis in the apple snail Pomacea canaliculata (Lamarck, 1822), with reference to the effects of xenobiotics

The complex array of male and female reproductive organs in Pomacea canaliculata develops from the gonoductal and copulatory primordia. These primordia are present in both sexes, but while the gonoductal primordium (or ‘gonoduct’) is present in hatchlings, the copulatory primordium only appears in juveniles at the 5-mm (shell length) stage. The proximal portion of the gonoduct will produce the gonad, while the more distal portions will produce the accessory sexual organs (the visceral vas deferens, pallial seminal vesicle, prostate and genital papilla in males, and the visceral oviduct, uterus and vagina in females). The gonadal portion of the gonoduct differentiates histologically into either the testis or the ovary at the 10-mm stage, while the more distal portions remain undifferentiated and the copulatory primordium remains approximately the same size in both sexes. The copulatory rudiment becomes larger in juvenile males at the 15-mm stage and rudiments of all adult components have appeared by then. At this stage, the pallial gonoduct differentiates into either the pallial seminal vesicle and prostate, or the uterus and vagina. Subadults at the 20-mm stage possess either some mature spermatogenic nests or some large oocytes. Crossing of the genital papilla over the rectum, a crucial event in male differentiation, has already occurred at this stage. Sexual differentiation of the operculum and the initiation of copulatory behaviour occur between the 15- and 20-mm stages, while oviposition begins c. 2 weeks later. Full development of gonoduct derivatives is reached at the 25-mm stage in both sexes. However, the copulatory structures remain rudimentary in females, even though they may still develop to some extent later on. These findings not only indicate two distinct origins of reproductive organs, but also several developmental stages during which different control mechanisms may operate. This has implications for understanding potential targets and responses to endocrine-disrupting xenobiotics.

Characterization of free endogenous sphingoid bases in the golden apple snail Pomacea canaliculata: involvement in snail development and nutrient limitation

A high-performance liquid chromatography-based method was developed for the analysis of free sphingoid bases endogenous to the golden apple snail (Pomacea canaliculata). Four molecular species of free endogenous sphingoid bases were observed in the snail and identified as C14 and C16 sphingosine (SPH), C14 dihydrosphingosine, and C16 sphingadienes with Δ-4,6 conjugated double bonds (Δ-4,6-C16 sphingadienes). When free endogenous sphingoid bases were evaluated at different stages of development of P. canaliculata, it was found that all four sphingoid bases decreased significantly from a young age to adulthood. We also found that the amount of C14 SPH decreased significantly in the food-restricted snails compared to animals with an adequate food supply, suggesting that nutrient deprivation decreases the levels of the sphingoid base. Taken together, these results suggest that sphingoid bases may play roles in the development of the golden apple snail and its stress response to nutrient limitation.