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Manh N Hoang - One of the best experts on this subject based on the ideXlab platform.
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water quality animal performance nutrient budgets and microbial community in the biofloc based Polyculture system of white shrimp litopenaeus vannamei and gray mullet mugil cephalus
Aquaculture, 2020Co-Authors: Manh N Hoang, Phuoc N Nguyen, Peter BossierAbstract:Abstract Shrimp Polyculture has not been common practice because it is mostly limited to extensive aquaculture systems. A combination of shrimp-fish Polyculture and biofloc technology may have the potential to substitute low intensive shrimp Polyculture systems. An indoor trial was conducted to investigate whether a biofloc-based co-culture of Litopenaeus vannamei and Mugil cephalus generates synergistic effects at the level of water quality, animal production, and nutrient budgets relative to co-culture and/or biofloc based monoculture. Shrimp (0.50 ± 0.16 g) were randomly distributed in 12 fiberglass tanks (5 m3) at a density of 80 shrimp.m-3. Six tanks were operated as shrimp monoculture either without biofloc (M-only) or with bioflocs (M-biofloc). The other six tanks were operated as Polyculture (Mugil cephalus size of 1.51 ± 0.02 g added at 10% stocking density of the shrimp biomass) either without biofloc (P-only) or with biofloc (P-biofloc). The results showed that water quality parameters, such as total ammonia nitrogen (TAN), nitrite, nitrate, phosphate were significantly lower in M-biofloc and P-biofloc than in other treatments (p
Peter Bossier - One of the best experts on this subject based on the ideXlab platform.
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water quality animal performance nutrient budgets and microbial community in the biofloc based Polyculture system of white shrimp litopenaeus vannamei and gray mullet mugil cephalus
Aquaculture, 2020Co-Authors: Manh N Hoang, Phuoc N Nguyen, Peter BossierAbstract:Abstract Shrimp Polyculture has not been common practice because it is mostly limited to extensive aquaculture systems. A combination of shrimp-fish Polyculture and biofloc technology may have the potential to substitute low intensive shrimp Polyculture systems. An indoor trial was conducted to investigate whether a biofloc-based co-culture of Litopenaeus vannamei and Mugil cephalus generates synergistic effects at the level of water quality, animal production, and nutrient budgets relative to co-culture and/or biofloc based monoculture. Shrimp (0.50 ± 0.16 g) were randomly distributed in 12 fiberglass tanks (5 m3) at a density of 80 shrimp.m-3. Six tanks were operated as shrimp monoculture either without biofloc (M-only) or with bioflocs (M-biofloc). The other six tanks were operated as Polyculture (Mugil cephalus size of 1.51 ± 0.02 g added at 10% stocking density of the shrimp biomass) either without biofloc (P-only) or with biofloc (P-biofloc). The results showed that water quality parameters, such as total ammonia nitrogen (TAN), nitrite, nitrate, phosphate were significantly lower in M-biofloc and P-biofloc than in other treatments (p
Qian Huang - One of the best experts on this subject based on the ideXlab platform.
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transmission pattern of the parasitic dinoflagellate hematodinium perezi in Polyculture ponds of coastal china
Aquaculture, 2021Co-Authors: Qian Huang, Fei Wang, Shuqun SongAbstract:Abstract Since 2012, Hematodinium perezi epizootics have occurred frequently in cultured swimming crabs Portunus trituberculatus in Polyculture ponds along the coast of Shandong Province, China. These outbreaks have resulted in significant economic losses to local farmers. The cryptic transmission pattern of H. perezi has hampered the prevention and control of the pathogen in affected farms. The mudflat crab Helice tientsinensis is one of the dominant wild crabs in the region with considerable prevalence of the parasitic infection covering the full culture period of P. trituberculatus. Mudflat crabs can migrate in and out of Polyculture ponds during water exchange and may act as an important reservoir host and source of H. perezi for newly seeded P. trituberculatus. During 2019, we carried out continuous field investigations and sentinel experiments in the Polyculture pond system, as well as a series of laboratory infection trials, to study whether waterborne transmission of H. perezi can occur in Polyculture ponds, and to determine whether H. perezi can be transmitted from H. tientsinensis to cultured P. trituberculatus. The sentinel experiment verified waterborne transmission of H. perezi to cultured P. trituberculatus in the Polyculture pond. The cohabitation trial further indicated that H. perezi was transmittable from H. tientsinensis to P. trituberculatus through waterborne transmission, whereas P. trituberculatus was not able to acquire H. perezi infection by feeding on tissues of infected H. tientsinensis. The results highlighted the transmission pattern of the parasitic dinoflagellate H. perezi in the Polyculture pond systems widely used along the coast line of China. In addition, the mudflat crab H. tientsinensis was confirmed as a reservoir host of H. perezi in the epidemic area, and confirmed as the likely source of the parasite during the intensive culture of P. trituberculatus.
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the parasitic dinoflagellate hematodinium infects multiple crustaceans in the Polyculture systems of shandong province china
Journal of Invertebrate Pathology, 2021Co-Authors: Qian Huang, Shuqun SongAbstract:The parasitic dinoflagellates of the Hematodinium genus have impacted wild and cultured stocks of commercial crustaceans worldwide. In the past decade, outbreaks of Hematodinium epizootics resulted in substantial mortalities in cultured Chinese swimming crabs Portunus trituberculatus in the Polyculture ponds located in Shandong Peninsula, whereas the source and transmission of the parasite in the Polyculture pond system remains to be determined. During April to December of 2018, 2034 crabs and 108 shrimps were collected from the Polyculture pond systems in the highly endemic area of Hematodinium diseases in Qingdao, Shandong Province. Among those, 188 individuals of the 6 crab species were infected by the parasite, including 4 novel host species (Uca arcuate, Hemigrapsus penicillatus, Helice wuana and Macrophthalmus japonicas). No infection was identified in Penaeus monodon. Further phylogenetic analyses indicated that the Hematodinium isolate infecting the six crab hosts, together with other isolates reported from China, composed the genotype II of Hematodinium perezi. The parasite was more infectious to cultured Portunus trituberculatus and the dominant wild crab Helice tientsinensis dwelling in the waterways connecting to the Polyculture ponds, even though it was found to be a host generalist pathogen. The prevalence of Hematodinium perezi infection in Helice tientsinensis was higher than that of other wild crabs and showed significant positive correlation with that of the cultured Portunus trituberculatus. The results indicated that the wild crabs, particularly Helice tientsinensis, were the important alternate hosts closely involved in transmission and spreading of the Hematodinium disease in the Polyculture pond systems.
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the parasitic dinoflagellate hematodinium perezi infecting mudflat crabs helice tientsinensis in Polyculture system in china
Journal of Invertebrate Pathology, 2019Co-Authors: Qian Huang, Fei WangAbstract:Abstract Since 2012, frequent outbreaks of Hematodinium diseases have significantly impacted sustainable culture of marine crabs Portunus trituberculatus in the coastal areas of Shandong Peninsula. The mechanisms of the Hematodinium parasite epizootics in Polyculture pond systems remain to be explored and alternate crustacean hosts are speculated to play important roles in transmission and epizootiology of the disease. To investigate their possible role in transmission, the common wild mudflat crabs Helice tientsinensis were sampled from the waterway connecting to Polyculture ponds in Huangdao, Qingdao, China and diagnosed for Hematodinium infection. Hematodinium infection was found in H. tientsinensis collected in the waterway from April–November 2018, with a prevalence of 5.8–31.7%. In addition, 23.1% of H. tientsinensis sampled from the adjacent Polyculture pond were infected during the peak of the Hematodinium epizootic in July. Amoeboid trophonts or prespores were observed in the hemolymph of the Hematodinium-infected crabs and histopathological changes were observed in major organs (e.g. hepatopancreas, heart, gill and muscle). The ITS1 rRNA of Hematodinium sp. infecting H. tientsinensis shared 99–100% similarity to isolates infecting P. trituberculatus and Penaeus monodon in local Polyculture ponds, and are included in a monophylogenetic clade, Hematodinium perezi genotype II, in the phylogenetic tree. The results further showed that this generalist parasite was infecting various types of marine crustaceans in the coastal waters of China, and that mudflat crabs H. tientsinensis may serve as an important alternate host during epizootics of Hematodinium parasites in the Polyculture system.
Shuqun Song - One of the best experts on this subject based on the ideXlab platform.
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transmission pattern of the parasitic dinoflagellate hematodinium perezi in Polyculture ponds of coastal china
Aquaculture, 2021Co-Authors: Qian Huang, Fei Wang, Shuqun SongAbstract:Abstract Since 2012, Hematodinium perezi epizootics have occurred frequently in cultured swimming crabs Portunus trituberculatus in Polyculture ponds along the coast of Shandong Province, China. These outbreaks have resulted in significant economic losses to local farmers. The cryptic transmission pattern of H. perezi has hampered the prevention and control of the pathogen in affected farms. The mudflat crab Helice tientsinensis is one of the dominant wild crabs in the region with considerable prevalence of the parasitic infection covering the full culture period of P. trituberculatus. Mudflat crabs can migrate in and out of Polyculture ponds during water exchange and may act as an important reservoir host and source of H. perezi for newly seeded P. trituberculatus. During 2019, we carried out continuous field investigations and sentinel experiments in the Polyculture pond system, as well as a series of laboratory infection trials, to study whether waterborne transmission of H. perezi can occur in Polyculture ponds, and to determine whether H. perezi can be transmitted from H. tientsinensis to cultured P. trituberculatus. The sentinel experiment verified waterborne transmission of H. perezi to cultured P. trituberculatus in the Polyculture pond. The cohabitation trial further indicated that H. perezi was transmittable from H. tientsinensis to P. trituberculatus through waterborne transmission, whereas P. trituberculatus was not able to acquire H. perezi infection by feeding on tissues of infected H. tientsinensis. The results highlighted the transmission pattern of the parasitic dinoflagellate H. perezi in the Polyculture pond systems widely used along the coast line of China. In addition, the mudflat crab H. tientsinensis was confirmed as a reservoir host of H. perezi in the epidemic area, and confirmed as the likely source of the parasite during the intensive culture of P. trituberculatus.
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the parasitic dinoflagellate hematodinium infects multiple crustaceans in the Polyculture systems of shandong province china
Journal of Invertebrate Pathology, 2021Co-Authors: Qian Huang, Shuqun SongAbstract:The parasitic dinoflagellates of the Hematodinium genus have impacted wild and cultured stocks of commercial crustaceans worldwide. In the past decade, outbreaks of Hematodinium epizootics resulted in substantial mortalities in cultured Chinese swimming crabs Portunus trituberculatus in the Polyculture ponds located in Shandong Peninsula, whereas the source and transmission of the parasite in the Polyculture pond system remains to be determined. During April to December of 2018, 2034 crabs and 108 shrimps were collected from the Polyculture pond systems in the highly endemic area of Hematodinium diseases in Qingdao, Shandong Province. Among those, 188 individuals of the 6 crab species were infected by the parasite, including 4 novel host species (Uca arcuate, Hemigrapsus penicillatus, Helice wuana and Macrophthalmus japonicas). No infection was identified in Penaeus monodon. Further phylogenetic analyses indicated that the Hematodinium isolate infecting the six crab hosts, together with other isolates reported from China, composed the genotype II of Hematodinium perezi. The parasite was more infectious to cultured Portunus trituberculatus and the dominant wild crab Helice tientsinensis dwelling in the waterways connecting to the Polyculture ponds, even though it was found to be a host generalist pathogen. The prevalence of Hematodinium perezi infection in Helice tientsinensis was higher than that of other wild crabs and showed significant positive correlation with that of the cultured Portunus trituberculatus. The results indicated that the wild crabs, particularly Helice tientsinensis, were the important alternate hosts closely involved in transmission and spreading of the Hematodinium disease in the Polyculture pond systems.
Holly Zafian - One of the best experts on this subject based on the ideXlab platform.
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the performance of native and non native turfgrass monocultures and native turfgrass Polycultures an ecological approach to sustainable lawns
Ecological Engineering, 2011Co-Authors: Mark T Simmons, Michelle Bertelsen, Steve Windhager, Holly ZafianAbstract:As environmental impacts and life-cycle costs (water use, water, fertilizer, pesticides and mowing) of the constructed landscape come under increasing scrutiny, the development of methods to reduce resource inputs for managed turf are increasingly important. While the use of a number of native turfgrass species as alternatives to non-natives has been previously examined, only a few are presently commercially available, and many species have been perceived as failing to perform to the level required by industry and consumers. Furthermore, the use of Polycultures of native turfgrasses has not been extensively investigated, but could offer an alternative to the conventional lawn. We hypothesize that because native short grass species would be expected to be well-adapted to climate and soil conditions in areas with infrequent and erratic rainfall, their performance in terms of drought resistance, resilience to disturbance, and efficient resource use, will exceed that of a non-native species. Moreover, ecological theory predicts that a Polyculture of coexisting native species may exhibit additional performance benefits. One native (Bouteloua dactyloides) and one commonly-used, non-native monoculture (Cynodon dactylon) and two native Polyculture assemblages (two and seven species including B. dactyloides, Bouteloua gracilis, Bouteloua rigidiseta, Hilaria belangeri, Erioneuron pilosum, Bouteloua hirsuta, Sporobolus vaginiflorus) were compared for leaf density and weed resistance under two irrigation regimens, traffic regimes and mowing intensities. The native turfgrass and turfgrass assemblages generally had 30% higher leaf densities in the early growing season, and up to 50% lower weed density than the non-native monoculture. There was no difference among species tested in response to traffic or irrigation regimens, suggesting that all assemblages could be subjected to both higher traffic frequencies and reduced water inputs. Even though native species can have slower growth rates compared to the non-native species they maintained a higher or equivalent leaf density than the non-native turfgrass. This is a potentially important finding because of the large impact that mowing has on the total carbon footprint of turfgrass, and the corresponding reduction in that carbon footprint that could be realized through a reduced mowing frequency and corresponding reduction in life-cycle cost. This study suggests that regionally adapted native grass species are worth investigating as mono- and Polycultures for performance advantages and lower resource inputs, and consequently may be suitable alternatives to conventional non-native turfgrasses in many applications. © 2011 Elsevier B.V. All rights reserved.
