Cutaneous larva migrans (CLM) is a zoonotic hookworm infection of dogs and cats commonly found in low-income countries in the tropical and subtropical regions and travellers to these regions. It is caused by invasion ...Cutaneous larva migrans (CLM) is a zoonotic hookworm infection of dogs and cats commonly found in low-income countries in the tropical and subtropical regions and travellers to these regions. It is caused by invasion of the skin by the parasitic larvae of hookworms which, after entry, move under the skin causing an inflammatory reaction resulting in a single or multiple tracks. Patients commonly present with a progressive, itchy, erythematous serpiginous skin rash, affecting the feet, although it can affect any other parts of the body. The diagnosis is mainly clinical, based on history and physical examination. Treatment of this condition can effectively be achieved with either albendazole or ivermectin. We present a case of a 7-year-old boy who was diagnosed with CLM after presenting to the hospital with a history of a progressive itchy rash with tracks on the left foot. Although CLM is a self-limiting disease, it causes a lot of suffering and, therefore, it is of public concern. There is a need to increase awareness of this disease among health workers, and to implement and promote preventive measures against the disease since the cause is known.展开更多
[Objectives]The paper was to screen effective biocontrol strains against Meloidogyne incognita.[Methods]The effect of six bacterial strains sourced from the research group s strain library on the activity of second in...[Objectives]The paper was to screen effective biocontrol strains against Meloidogyne incognita.[Methods]The effect of six bacterial strains sourced from the research group s strain library on the activity of second instar larvae of M.incognita,as well as on egg hatching,was evaluated.[Results]The treatment of fermentation supernatant derived from the X-2 strain exhibited a pronounced lethal effect on M.incognita,with a corrected mortality rate reaching 97%within 72 h.Additionally,this treatment significantly inhibited egg hatching,achieving an inhibition rate of 94.69%at a 20-fold dilution.The strain was identified as Bacillus velezensis,belonging to the genus Bacillus,and was designated as RKN1111.[Conclusions]This study presents alternative strains and a theoretical framework for the biological control of M.incognita.展开更多
[ Objective ] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp. [ Method ] The heterobacteria, vibr...[ Objective ] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp. [ Method ] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system. [ Result] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius, then their number would increase with growth. During whole rearing period, both boterobacteria in larvae, vibrios in water would increase by one order of magnitude, while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude. There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait. The correlation coefficients between larvae and heterobacteria and vibrios in water were 0. 704 and 0. 840 in culture system respectively, while the correlation among heterobacteria, vibrios in living bait and larvae, water were weak or negative. [ Conclusion ] There was a dynamic relation between water and larvae in rearing period, and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus, besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system.展开更多
[Objective] The aim was to explore key technology to cultivate Holotdchia diomphalia larvae with Agaricus bisporus residues and to provide, technologicar sup- ports for processing of Agaricus bisporus residues. [Metho...[Objective] The aim was to explore key technology to cultivate Holotdchia diomphalia larvae with Agaricus bisporus residues and to provide, technologicar sup- ports for processing of Agaricus bisporus residues. [Method] In the research, fodder thickness, population density and residues under different treatments were set to re- search effects on Holotrichia diomphalia larvae. [Result] The optimal thickness of fodder was 25 cm and the optimal feeding density was 44-56 larvae per hectare. The dry residues were more suitable, compared with decomposed residues and corn bran powders, for cultivation of Holotrichia diomphalia larvae. [Conclusion] Cultivation of Holotrichia diomphalia larvae with Agaricus bisporus residues is a new method to make use of Agaricus bisporus residues and of significance for extension of agricul- tural circulation chain, increase of economic benefits and ecological benefits.展开更多
In order to solve the seasonal supply problem of Clanis bilineata Walker larvae,effects of larva instar,time and temperature on larvae preservation were studied in this experiment.The results indicated that the 5th in...In order to solve the seasonal supply problem of Clanis bilineata Walker larvae,effects of larva instar,time and temperature on larvae preservation were studied in this experiment.The results indicated that the 5th instar mature larvae had the best preservation durability,and their optimum preservation condition was 2-4 ℃ with a upper time limit of 8 months.展开更多
The morphological characters on different developmental phases of embryo and larva and the schedule of the whole early developmental process in Styela canopus were observed and described. The types of reproduction and...The morphological characters on different developmental phases of embryo and larva and the schedule of the whole early developmental process in Styela canopus were observed and described. The types of reproduction and early development as well as the morphology, of egg and larva in different ascidian species were compared. Styela canopus is oviparous. Its egg, 230.4 similar to 336.0 mum in diameter, is equipped with extraembryonic cell layers measured 43.2 similar to 63.0 mum thick. The early development of Styela canopus is typical urodele development, including fertilization, cleavage, gastrulation, tadpole in membrane, tadpole, initiating metamorphosis and juvenile. The tadpole of Styela canopus, with a length of 0.6 similar to 0. 9 mm, consists of trunk and tail. There are obvious notochord, ocellus and adhesive papillae in the tadpole. Under the water temperature of (25 +/- 0-5) degreesC and the salinity of 27.0, the larva was hatched after 9.5 similar to 11.0 h since the fertilization.展开更多
[ Objective] The paper was to understand the biological characteristics of bananamoth [ Opogona sacchari ( Bojer ) ] larvae in sugarcane. [ Method ] Through the rearing test of bananamoth larvae with different hosts...[ Objective] The paper was to understand the biological characteristics of bananamoth [ Opogona sacchari ( Bojer ) ] larvae in sugarcane. [ Method ] Through the rearing test of bananamoth larvae with different hosts, the biological characteristics of bananamoth larvae in sugarcane were observed and analyzed. [ Result ] The mortality rate of bananamoth larvae reared with sugarcane was higher than that of the pests reared with potato. The larva had 8 instars, and the devel- opment duration of the larvae reared with sugarcane was 34.6 d longer than the pests reared with potato. The larvae needed about 98.8 d to complete a generation in average. Viewed from the observation values of head width, body length and weight of larvae, bananamoth larvae reared with sugarcane basically accorded with the growth and development law of larvae. [Condusion ] The results provided theoretical basis for the preparation of effective measures against bananamoth and the assurance of safe production of.sugarcane.展开更多
In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatch...In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatching of A. japonicus, and the larval survival rate, disease incidence rate and economic benefit were analyzed. The results showed that compared with those of conventional temperature-reared larvae, the survival rate of raised temperature-reared larvae was increased by 15.8%, the disease incidence rate was reduced by 10.2%, and the economic benefit was improved by 21.6%. These results will provide theoretical basis and technical support for the artificial breeding of A. japonicus.展开更多
The larval external morphologies of Eupithecia abietaria debrunneata Stau dinger, Eupithecia spadix Inoue and Telenomeuta punctimarginaria (Leech) of Larentiinae are described.
A chironomid larvae images recognition method based on wavelet energy feature and improved KNN is developed. Wavelet decomposition and color information entropy are selected to construct vectors for KNN that is used t...A chironomid larvae images recognition method based on wavelet energy feature and improved KNN is developed. Wavelet decomposition and color information entropy are selected to construct vectors for KNN that is used to classify of the images. The distance function is modified according to the weight determined by the correlation degree between feature and class, which effectively improves classification accuracy. The result shows the mean accuracy of classification rate is up to 95.41% for freshwater plankton images, such as chironomid larvae, cyclops and harpacticoida.展开更多
Eight kinds of phytoecdysteroids extracted from different parts of Ajuga multiflora Bunge (Labiatae) that were collected from different places at different time were tested for killing effects on the 2-instar larvae o...Eight kinds of phytoecdysteroids extracted from different parts of Ajuga multiflora Bunge (Labiatae) that were collected from different places at different time were tested for killing effects on the 2-instar larvae of Cryptorrhynchus lapathi L by adding them to the artificial diet of larvae. The experimental results indicated that adding 1-3-mL phytoecdysteroids to the artificial diet could lead 58%-100% of 2-instar larvae of C. lapathi to death within 24 days. The phytoecdysteroids extracted from the whole plant of A. multiflora which was collected before flowering time were much more effective than those extracted from the plants collected at flowering and after flowering periods, and the modified mortality rate of larvae reached 65.22%, 85.07%, and 98.11% at the dosage level of 1-mL, 2-mL, and 3-mL extracts, respectively. The extract made from root of A. multiflora plant was more effective in killing efficiency than those from stem and leaves, and the average death rates of larvae were up to 100%, 98.20% and 98.32% at dosage levels of 1-mL, 2-mL, and 3-mL extracts, respectively. The killing speed of the extracted phytoecdysteroids was slower than that of triflumuron, hexaflumuron or deltamethrin emulsifiable concentrate. The mortality rate of larvae is closely related to the feeding duration on the diets containing phytoecdysteroids. Feeding on the diets with addition of phytoecdysteroids for 16 days, more than 80% of treated 2-instar larvae of C. lapathi were led to death. The killing effect of the extracts was little affected by the growth areas of A. multiflora plant and the adding way to artificial diet.展开更多
Cutaneous larva migrans(CLM) represents the most common tropically acquired dermatosis.CLM is caused by infection with hookworm larvae in tropical and sub-tropical areas,and people who have a history of foreign travel...Cutaneous larva migrans(CLM) represents the most common tropically acquired dermatosis.CLM is caused by infection with hookworm larvae in tropical and sub-tropical areas,and people who have a history of foreign travel and of walking barefoot on sandy soil or beaches are at a high risk of getting infected with it.The diagnosis is usually made on the basis of the typical appearance of the lesion,intense itching and history of foreign travel.CLM is a common parasitic skin disease that can be easily prevented by wearing 'protective' footwear.A case of CLM is described in this article.展开更多
Background:The possibility of partially replacing soybean meal(SBM)with Hermetia illucens(HI)defatted larvae meal in broiler nutrition has frequently been suggested.For sustainability reasons,however,the larvae fat pr...Background:The possibility of partially replacing soybean meal(SBM)with Hermetia illucens(HI)defatted larvae meal in broiler nutrition has frequently been suggested.For sustainability reasons,however,the larvae fat produced during defatting should also be used and could be particularly beneficial regarding gut health due to its fatty acid composition.To evaluate the suitability of HI larvae as protein and fat source,a 2×3 factorial arrangement with two types of protein,i.e.SBM(S)or SBM and 15%of its crude protein replaced by HI larvae meal(L),and three levels of fat sources,namely 0(0 L),50%(50 L)or 100%HI larvae fat(100 L)at the expense of soybean oil was applied.Results:In the starter phase,an interaction showed higher body weight(BW),average daily gain(ADG)and improved feed conversion ratio(FCR)if 50%or 100%HI larvae fat was fed with HI larvae meal.Moreover,BW,ADG and FCR improved when feeding HI larvae meal as protein source.Additionally,we observed an increased average daily feed intake in the grower,finisher,and overall phase in the L groups and an improved FCR in 0 L compared to 50 L groups during the overall period.Regarding apparent ileal digestibility,HI larvae meal feeding increased dry matter,organic matter,and fat digestibility.Feeding HI larvae meal as protein source decreased the concentrations of agmatine,spermidine,spermine and ammonia in the caecal digesta,whereas fat source affected agmatine with higher concentrations in 50 L compared to 0 L in the colonic digesta.In contrast,caecal ethanolamine concentrations increased in HI larvae meal groups compared to SBM.Caecal butyric acid concentrations decreased with HI larvae meal feeding.An interaction was found for the jejunal villus area,being higher in L+100 L compared to S+100 L.Furthermore,L groups had greater villus width.Conclusions:A partial replacement of SBM with HI larvae meal and soybean oil with HI larvae fat in broiler diets without impairing animal performance or gut health seems possible.Feeding HI larvae meal affected broiler performance positively in the starter phase and improved apparent ileal digestibility.展开更多
Objective:To evaluate the effectiveness and residual effects of trypsin modulating ecstatic factor-Bacillus thuringiensis israeliensis(TMOF-Bti) formulations against Aedes aegypti(Ae. aegypti)(L) larvae at UKM Campus ...Objective:To evaluate the effectiveness and residual effects of trypsin modulating ecstatic factor-Bacillus thuringiensis israeliensis(TMOF-Bti) formulations against Aedes aegypti(Ae. aegypti)(L) larvae at UKM Campus Kuala Lumpur.Methods:Twenty first instar Ae.aegypti larvae were added in each bucket containing 4 L of water supplied with crushed dried-leaf powder as their source of food.Combination of TMOF-Bti in rice husk formulation with the following weights viz 10,25,50 and 100 mg,respectively in duplicate was distributed in the buckets;while TMOF-Bti in wettable powder formulation each weighing viz 2,5,10 and 20 mg,respectively in duplicate was also placed in the buckets.The control buckets run in duplicate with 4 L of water and 20 first instar Ae.aegypti larvae.All buckets were covered with mosquito netting.Larval mortality was recorded after 24 hours and weekly for five weeks.A new batch of 20 1^(st) instar larvae Ae.aegypti was introduced into each bucket weekly without additional TMOF-Bti rice husk formulation or wettable powder.The experiment was repeated for four times.Results:The result of the study showed that all formulations were very effective on the first two weeks by giving 100% larval mortality for all concentrations applied.The TMOF(2%) + Bti(2%) had a good residual effect until the end of 3^(rd) week,TMOF(4%) + Bti(4%) until 4^(th) week,wettable powder TMOF(20%) + Bti(20%) until the third week.Condusions:From the results it can be concluded that the TMOF-Bti formulations can be utilized in dengue vector control.展开更多
Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. i...Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred(Duroc × Landrace × Large White) female pigs(initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet(Control group) and two diets corresponding to 4%(H1 group) and 8%(H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens(replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment(n =8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.Results: The results showed that the H1 diet significantly increased the abundance of Lactobacillus,Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group(P < 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group(P < 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group(P < 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group(P < 0.05);the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower(P < 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group(P < 0.05), while decreased the concentrations of phenol, p-cresol, and skatole(P < 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines(IFN-γ) compared with pigs in the control group(P < 0.05), and up-regulated anti-inflammatory cytokine(IL-10) and intestinal barrier genes(ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group(P < 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.Conclusions: Collectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.展开更多
Decreasing fish resources in estuaries is a subject of anthropogenic activities. Studies of the spatiotemporal distribution of fish eggs and larvae can help identify the status and processes underlying recruitment in ...Decreasing fish resources in estuaries is a subject of anthropogenic activities. Studies of the spatiotemporal distribution of fish eggs and larvae can help identify the status and processes underlying recruitment in a fishery. As the fifth largest river estuary in the world, the Huanghe (Yellow) River estuary (HRE) is a typical estuary that has been seriously aff ected by human activities. Annual surveys on ichthyoplankton and environmental factors were conducted in the months of May of 2005 and 2009-2016 in the HRE to investigate the spatiotemporal distribution of fish eggs and larvae and the associated infl uencing factors. A total of 23 and 20 species of eggs and larvae, respectively, were collected. The dominant orders were Perciformes (51.2%) and Clupeiformes (25.6%). The average number of fish species eggs and larvae were 6.0 and 4.1 in average abundance of 0.91 and 0.13 ind./m^3 , respectively. The dominant species were mainly low-commercial-value small-sized fishes, such as Clupanodon punctatus , Harengula zunasi, and Acanthogobius, whereas certain traditional commercial fishes, such as Trichiurus lepturus , and Clupea pallasii, were not seen. Analysis of the fish egg and larval community revealed four temporal assemblages and two spatial assemblages. Salinity was the main factor on the spatial distribution of ichthyoplankton communities, the species number and Shannon-Weiner diversity index (H′) of the fish egg and larval community near the river mouth with lower salinity were signifi cantly lower than the community far away from the river mouth with higher salinity. In addition, increases of water temperature promoted the number and abundance of fish species eggs, and the areas of abundant prey tended to have a more diversified and abundant of ichthyoplankton species. In overall, overfishing, dam construction, and other human activities were the main drivers that led to the substantial decline in fishery resources in the HRE.展开更多
Objective:To determine lead level primarily in Culex quinquefasciatus(Cx.quinquefasciatus), and Culex gelidus(Cx.gelidus) larvae inhabiting lead consuming factories,and to putatively estimate eco-toxicological impact ...Objective:To determine lead level primarily in Culex quinquefasciatus(Cx.quinquefasciatus), and Culex gelidus(Cx.gelidus) larvae inhabiting lead consuming factories,and to putatively estimate eco-toxicological impact of effluents from the firms.Methods:Third instars larvae were sampled by standard dipping method and lead concentrations in the larvae and their respective surrounding factory aquatic environments were determined through standard atomic absorption spectrophotometry(AAS).Results:Cx.quinquefasciatus was the most abundant species followed by Cx.gelidus.The levels of lead were higher in the Cx.quinquefasciatus(1.08-47.47μg/g),than in the wastewaters surface(0.01-0.78 μg/mL) from the factories or closer areas around factories. Other species were not reaching the.criteria for lead determination.Conclusions:The Cx. quinquefasciatus larvae can bio-accumulate the metal and can potentially serve as a biomarker of lead contamination,to complemente conventional techniques.展开更多
In order to improve production and breed new broods of bay scallop Argopecten irradians irradians, different-colored orange, purple and white lines were established by two mating methods of self-fertilization and mass...In order to improve production and breed new broods of bay scallop Argopecten irradians irradians, different-colored orange, purple and white lines were established by two mating methods of self-fertilization and mass spawning at a commercial scallop hatchery in spring, 2002. And then larval growth and survival of different lines was compared to test whether there is a relationship between shell color and growth and survival at early developmental stage. Both growth and survival have no significant differences among different experimental larvae of self-fertilization or mass spawning. Results are as following in the order of orange, purple and white shell stock. For the self-fertilization, growth rates of larvae were 6.174, 6.412, and 6.599 μm/d, respectively. Survival rates of larvae at Day 3 were 74.41%, 76.86%, and 82.05%; Day 6 were 49.14%, 65.63%, and 52.79%; and Day 9 were 25.06%, 20.80%, and 26.47%, respectively. For the mass spawning, the growth rates were 7.836, 7.941, and 7.878 μm/d, respectively. Survival rates at Day 3 were 93.05%, 91.95%, and 92.50%; Day 6 were 79.17%, 78.05%, and 82.50%; and Day 9 were 34.72%, 36.67%, and 38.33%, respectively. The absence of any relationship between shell color and growth and survival at the larval stage may be resulted from their common genetic basis.展开更多
During the First Chinese Antarctic Expedition zooplankton samples were collected at each of the oceanography stations in the waters around South Sheltland Islands (S. S. Is.) and in the northern part of the Bellinshau...During the First Chinese Antarctic Expedition zooplankton samples were collected at each of the oceanography stations in the waters around South Sheltland Islands (S. S. Is.) and in the northern part of the Bellinshausen Sea from 20 January to 12 February, 1985 by vertical tows of an 80 cm diameter conical net from 200 m to surface. Two deep tows with a closing net. were performed in slope water north of S.S. Is, and in the basin of Bransfield Strait. Eggs and larvae of Euphatisia superba Dana in zooplankton samples were identified and counted.There were four records of eggs from 27 stations. Most catches were of small number and restricted to within the nearshore area south of S.S Is.The largest number (1500/1000 cubic meters )was found in the outer side of Smith Island.No Nauplius was found . The earliest stage we found 【was Metanauplius , in two deep tows. The distribution of Calyptopis MI and Furcili I-III were quite similar. They were found mainly in three areas: 1 ) nearshore water along the展开更多
In laboratory conditions,effects of rearing temperature and stocking density were examined on hatching of fertilized egg and growth of auricularia larvae of Apostichopus japonicus respectively.Data series like larval ...In laboratory conditions,effects of rearing temperature and stocking density were examined on hatching of fertilized egg and growth of auricularia larvae of Apostichopus japonicus respectively.Data series like larval length and density,metamorphic time,and survival rate of the larvae were recorded.Statistics showed that for A.japonicus,survival rate(from fertilized egg to late auricularia) decreased significantly with the increasing rearing temperature(P<0.05).At different temperatures SGR was statistically significant as well(P<0.05) from day 1,and maximal SGR was found on day 9 at 24℃(159.26±3.28).This study clearly indicated that at low temperature(<24℃),metamorphic rate was remarkably higher than at higher temperature(>26℃).Hatching rate was significantly different between 0.2-5 ind./ml groups and 20-50 ind./ml groups.Rearing larvae at the higher density had the smaller maximal-length,whereas needed longer time to complete metamorphosis.This study suggested that 21℃ and 0.4 ind./ml can be used as the most suitable rearing temperature and stocking density for large-scale artificial breeding of A.japonicus's larvae.展开更多
文摘Cutaneous larva migrans (CLM) is a zoonotic hookworm infection of dogs and cats commonly found in low-income countries in the tropical and subtropical regions and travellers to these regions. It is caused by invasion of the skin by the parasitic larvae of hookworms which, after entry, move under the skin causing an inflammatory reaction resulting in a single or multiple tracks. Patients commonly present with a progressive, itchy, erythematous serpiginous skin rash, affecting the feet, although it can affect any other parts of the body. The diagnosis is mainly clinical, based on history and physical examination. Treatment of this condition can effectively be achieved with either albendazole or ivermectin. We present a case of a 7-year-old boy who was diagnosed with CLM after presenting to the hospital with a history of a progressive itchy rash with tracks on the left foot. Although CLM is a self-limiting disease, it causes a lot of suffering and, therefore, it is of public concern. There is a need to increase awareness of this disease among health workers, and to implement and promote preventive measures against the disease since the cause is known.
基金Supported by Key R&D Project of Science&Technology Department of Ningxia Hui Autonomous Region(2021BBF02013)Post-doctoral Program of Hebei Province(2019003011)Hebei Province Innovation Ability Enhancement Plan Project(225676109H).
文摘[Objectives]The paper was to screen effective biocontrol strains against Meloidogyne incognita.[Methods]The effect of six bacterial strains sourced from the research group s strain library on the activity of second instar larvae of M.incognita,as well as on egg hatching,was evaluated.[Results]The treatment of fermentation supernatant derived from the X-2 strain exhibited a pronounced lethal effect on M.incognita,with a corrected mortality rate reaching 97%within 72 h.Additionally,this treatment significantly inhibited egg hatching,achieving an inhibition rate of 94.69%at a 20-fold dilution.The strain was identified as Bacillus velezensis,belonging to the genus Bacillus,and was designated as RKN1111.[Conclusions]This study presents alternative strains and a theoretical framework for the biological control of M.incognita.
基金the National High Technology Research and Development Program of China (863 Program) (2006AA10A406)National Key Technology Research and Development Program of China (2006BAD01A13)Public Agriculture Specific Research Program (nyhyzx07-042)~~
文摘[ Objective ] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp. [ Method ] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system. [ Result] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius, then their number would increase with growth. During whole rearing period, both boterobacteria in larvae, vibrios in water would increase by one order of magnitude, while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude. There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait. The correlation coefficients between larvae and heterobacteria and vibrios in water were 0. 704 and 0. 840 in culture system respectively, while the correlation among heterobacteria, vibrios in living bait and larvae, water were weak or negative. [ Conclusion ] There was a dynamic relation between water and larvae in rearing period, and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus, besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system.
基金Supported by the National Key Technology R&D Program (2007BAD89B09-10)National Public Service Project (200803033-A0903)~~
文摘[Objective] The aim was to explore key technology to cultivate Holotdchia diomphalia larvae with Agaricus bisporus residues and to provide, technologicar sup- ports for processing of Agaricus bisporus residues. [Method] In the research, fodder thickness, population density and residues under different treatments were set to re- search effects on Holotrichia diomphalia larvae. [Result] The optimal thickness of fodder was 25 cm and the optimal feeding density was 44-56 larvae per hectare. The dry residues were more suitable, compared with decomposed residues and corn bran powders, for cultivation of Holotrichia diomphalia larvae. [Conclusion] Cultivation of Holotrichia diomphalia larvae with Agaricus bisporus residues is a new method to make use of Agaricus bisporus residues and of significance for extension of agricul- tural circulation chain, increase of economic benefits and ecological benefits.
文摘In order to solve the seasonal supply problem of Clanis bilineata Walker larvae,effects of larva instar,time and temperature on larvae preservation were studied in this experiment.The results indicated that the 5th instar mature larvae had the best preservation durability,and their optimum preservation condition was 2-4 ℃ with a upper time limit of 8 months.
文摘The morphological characters on different developmental phases of embryo and larva and the schedule of the whole early developmental process in Styela canopus were observed and described. The types of reproduction and early development as well as the morphology, of egg and larva in different ascidian species were compared. Styela canopus is oviparous. Its egg, 230.4 similar to 336.0 mum in diameter, is equipped with extraembryonic cell layers measured 43.2 similar to 63.0 mum thick. The early development of Styela canopus is typical urodele development, including fertilization, cleavage, gastrulation, tadpole in membrane, tadpole, initiating metamorphosis and juvenile. The tadpole of Styela canopus, with a length of 0.6 similar to 0. 9 mm, consists of trunk and tail. There are obvious notochord, ocellus and adhesive papillae in the tadpole. Under the water temperature of (25 +/- 0-5) degreesC and the salinity of 27.0, the larva was hatched after 9.5 similar to 11.0 h since the fertilization.
基金Supported by Special Fund for Industrial Technology System Construction of Modern Agriculture (nycytx-024-01-07)Research Special Fund for PublicService Sectors (Agriculture) (200903004)~~
文摘[ Objective] The paper was to understand the biological characteristics of bananamoth [ Opogona sacchari ( Bojer ) ] larvae in sugarcane. [ Method ] Through the rearing test of bananamoth larvae with different hosts, the biological characteristics of bananamoth larvae in sugarcane were observed and analyzed. [ Result ] The mortality rate of bananamoth larvae reared with sugarcane was higher than that of the pests reared with potato. The larva had 8 instars, and the devel- opment duration of the larvae reared with sugarcane was 34.6 d longer than the pests reared with potato. The larvae needed about 98.8 d to complete a generation in average. Viewed from the observation values of head width, body length and weight of larvae, bananamoth larvae reared with sugarcane basically accorded with the growth and development law of larvae. [Condusion ] The results provided theoretical basis for the preparation of effective measures against bananamoth and the assurance of safe production of.sugarcane.
文摘In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatching of A. japonicus, and the larval survival rate, disease incidence rate and economic benefit were analyzed. The results showed that compared with those of conventional temperature-reared larvae, the survival rate of raised temperature-reared larvae was increased by 15.8%, the disease incidence rate was reduced by 10.2%, and the economic benefit was improved by 21.6%. These results will provide theoretical basis and technical support for the artificial breeding of A. japonicus.
基金Supported by the National Natural Science Foundation of China(50778048)(60803096)the Natural Science Foundation of Hei-longjiang Province(E200812)China Postdoctoral ScienceFoundation Funded Project(20070420882)~~
文摘A chironomid larvae images recognition method based on wavelet energy feature and improved KNN is developed. Wavelet decomposition and color information entropy are selected to construct vectors for KNN that is used to classify of the images. The distance function is modified according to the weight determined by the correlation degree between feature and class, which effectively improves classification accuracy. The result shows the mean accuracy of classification rate is up to 95.41% for freshwater plankton images, such as chironomid larvae, cyclops and harpacticoida.
基金This paper was supported by National Natural Science Foundation of China(39970620)the"TRAPOYT"
文摘Eight kinds of phytoecdysteroids extracted from different parts of Ajuga multiflora Bunge (Labiatae) that were collected from different places at different time were tested for killing effects on the 2-instar larvae of Cryptorrhynchus lapathi L by adding them to the artificial diet of larvae. The experimental results indicated that adding 1-3-mL phytoecdysteroids to the artificial diet could lead 58%-100% of 2-instar larvae of C. lapathi to death within 24 days. The phytoecdysteroids extracted from the whole plant of A. multiflora which was collected before flowering time were much more effective than those extracted from the plants collected at flowering and after flowering periods, and the modified mortality rate of larvae reached 65.22%, 85.07%, and 98.11% at the dosage level of 1-mL, 2-mL, and 3-mL extracts, respectively. The extract made from root of A. multiflora plant was more effective in killing efficiency than those from stem and leaves, and the average death rates of larvae were up to 100%, 98.20% and 98.32% at dosage levels of 1-mL, 2-mL, and 3-mL extracts, respectively. The killing speed of the extracted phytoecdysteroids was slower than that of triflumuron, hexaflumuron or deltamethrin emulsifiable concentrate. The mortality rate of larvae is closely related to the feeding duration on the diets containing phytoecdysteroids. Feeding on the diets with addition of phytoecdysteroids for 16 days, more than 80% of treated 2-instar larvae of C. lapathi were led to death. The killing effect of the extracts was little affected by the growth areas of A. multiflora plant and the adding way to artificial diet.
文摘Cutaneous larva migrans(CLM) represents the most common tropically acquired dermatosis.CLM is caused by infection with hookworm larvae in tropical and sub-tropical areas,and people who have a history of foreign travel and of walking barefoot on sandy soil or beaches are at a high risk of getting infected with it.The diagnosis is usually made on the basis of the typical appearance of the lesion,intense itching and history of foreign travel.CLM is a common parasitic skin disease that can be easily prevented by wearing 'protective' footwear.A case of CLM is described in this article.
基金supported by the Federal Ministry Republic of Austria,Agriculture,Regions and Tourism(LE 14-20,Application number 16.1.1-S2-23/18 and 16.2.1.-S2-23/18),within an EIP-Project.
文摘Background:The possibility of partially replacing soybean meal(SBM)with Hermetia illucens(HI)defatted larvae meal in broiler nutrition has frequently been suggested.For sustainability reasons,however,the larvae fat produced during defatting should also be used and could be particularly beneficial regarding gut health due to its fatty acid composition.To evaluate the suitability of HI larvae as protein and fat source,a 2×3 factorial arrangement with two types of protein,i.e.SBM(S)or SBM and 15%of its crude protein replaced by HI larvae meal(L),and three levels of fat sources,namely 0(0 L),50%(50 L)or 100%HI larvae fat(100 L)at the expense of soybean oil was applied.Results:In the starter phase,an interaction showed higher body weight(BW),average daily gain(ADG)and improved feed conversion ratio(FCR)if 50%or 100%HI larvae fat was fed with HI larvae meal.Moreover,BW,ADG and FCR improved when feeding HI larvae meal as protein source.Additionally,we observed an increased average daily feed intake in the grower,finisher,and overall phase in the L groups and an improved FCR in 0 L compared to 50 L groups during the overall period.Regarding apparent ileal digestibility,HI larvae meal feeding increased dry matter,organic matter,and fat digestibility.Feeding HI larvae meal as protein source decreased the concentrations of agmatine,spermidine,spermine and ammonia in the caecal digesta,whereas fat source affected agmatine with higher concentrations in 50 L compared to 0 L in the colonic digesta.In contrast,caecal ethanolamine concentrations increased in HI larvae meal groups compared to SBM.Caecal butyric acid concentrations decreased with HI larvae meal feeding.An interaction was found for the jejunal villus area,being higher in L+100 L compared to S+100 L.Furthermore,L groups had greater villus width.Conclusions:A partial replacement of SBM with HI larvae meal and soybean oil with HI larvae fat in broiler diets without impairing animal performance or gut health seems possible.Feeding HI larvae meal affected broiler performance positively in the starter phase and improved apparent ileal digestibility.
基金financially supported by Entogenex Industries Sdn.Bhd.,Malaysia(grant No.NN 001-2008)
文摘Objective:To evaluate the effectiveness and residual effects of trypsin modulating ecstatic factor-Bacillus thuringiensis israeliensis(TMOF-Bti) formulations against Aedes aegypti(Ae. aegypti)(L) larvae at UKM Campus Kuala Lumpur.Methods:Twenty first instar Ae.aegypti larvae were added in each bucket containing 4 L of water supplied with crushed dried-leaf powder as their source of food.Combination of TMOF-Bti in rice husk formulation with the following weights viz 10,25,50 and 100 mg,respectively in duplicate was distributed in the buckets;while TMOF-Bti in wettable powder formulation each weighing viz 2,5,10 and 20 mg,respectively in duplicate was also placed in the buckets.The control buckets run in duplicate with 4 L of water and 20 first instar Ae.aegypti larvae.All buckets were covered with mosquito netting.Larval mortality was recorded after 24 hours and weekly for five weeks.A new batch of 20 1^(st) instar larvae Ae.aegypti was introduced into each bucket weekly without additional TMOF-Bti rice husk formulation or wettable powder.The experiment was repeated for four times.Results:The result of the study showed that all formulations were very effective on the first two weeks by giving 100% larval mortality for all concentrations applied.The TMOF(2%) + Bti(2%) had a good residual effect until the end of 3^(rd) week,TMOF(4%) + Bti(4%) until 4^(th) week,wettable powder TMOF(20%) + Bti(20%) until the third week.Condusions:From the results it can be concluded that the TMOF-Bti formulations can be utilized in dengue vector control.
基金supported by the Presidential Foundation of the Guangdong Academy of Agricultural Sciences(201802B,201621)Guangdong Modern Agro-industry Technology Research System(2016LM1080,2017LM1080)
文摘Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred(Duroc × Landrace × Large White) female pigs(initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet(Control group) and two diets corresponding to 4%(H1 group) and 8%(H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens(replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment(n =8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.Results: The results showed that the H1 diet significantly increased the abundance of Lactobacillus,Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group(P < 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group(P < 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group(P < 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group(P < 0.05);the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower(P < 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group(P < 0.05), while decreased the concentrations of phenol, p-cresol, and skatole(P < 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines(IFN-γ) compared with pigs in the control group(P < 0.05), and up-regulated anti-inflammatory cytokine(IL-10) and intestinal barrier genes(ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group(P < 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.Conclusions: Collectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.
基金Supported by the National Natural Science Foundation of China—Shandong Provincial Joint Fund for Marine Science Research Centers(No.U1606404)the National Key Basic Research Program of China(973 Program)(No.2015CB453301)the National Marine Public Welfare Research Project of China(No.201405007)
文摘Decreasing fish resources in estuaries is a subject of anthropogenic activities. Studies of the spatiotemporal distribution of fish eggs and larvae can help identify the status and processes underlying recruitment in a fishery. As the fifth largest river estuary in the world, the Huanghe (Yellow) River estuary (HRE) is a typical estuary that has been seriously aff ected by human activities. Annual surveys on ichthyoplankton and environmental factors were conducted in the months of May of 2005 and 2009-2016 in the HRE to investigate the spatiotemporal distribution of fish eggs and larvae and the associated infl uencing factors. A total of 23 and 20 species of eggs and larvae, respectively, were collected. The dominant orders were Perciformes (51.2%) and Clupeiformes (25.6%). The average number of fish species eggs and larvae were 6.0 and 4.1 in average abundance of 0.91 and 0.13 ind./m^3 , respectively. The dominant species were mainly low-commercial-value small-sized fishes, such as Clupanodon punctatus , Harengula zunasi, and Acanthogobius, whereas certain traditional commercial fishes, such as Trichiurus lepturus , and Clupea pallasii, were not seen. Analysis of the fish egg and larval community revealed four temporal assemblages and two spatial assemblages. Salinity was the main factor on the spatial distribution of ichthyoplankton communities, the species number and Shannon-Weiner diversity index (H′) of the fish egg and larval community near the river mouth with lower salinity were signifi cantly lower than the community far away from the river mouth with higher salinity. In addition, increases of water temperature promoted the number and abundance of fish species eggs, and the areas of abundant prey tended to have a more diversified and abundant of ichthyoplankton species. In overall, overfishing, dam construction, and other human activities were the main drivers that led to the substantial decline in fishery resources in the HRE.
文摘Objective:To determine lead level primarily in Culex quinquefasciatus(Cx.quinquefasciatus), and Culex gelidus(Cx.gelidus) larvae inhabiting lead consuming factories,and to putatively estimate eco-toxicological impact of effluents from the firms.Methods:Third instars larvae were sampled by standard dipping method and lead concentrations in the larvae and their respective surrounding factory aquatic environments were determined through standard atomic absorption spectrophotometry(AAS).Results:Cx.quinquefasciatus was the most abundant species followed by Cx.gelidus.The levels of lead were higher in the Cx.quinquefasciatus(1.08-47.47μg/g),than in the wastewaters surface(0.01-0.78 μg/mL) from the factories or closer areas around factories. Other species were not reaching the.criteria for lead determination.Conclusions:The Cx. quinquefasciatus larvae can bio-accumulate the metal and can potentially serve as a biomarker of lead contamination,to complemente conventional techniques.
基金This work was financially supported by Project of Scientific Innova-tion, Chinese Academy of Sciences (ZKCX2-211).
文摘In order to improve production and breed new broods of bay scallop Argopecten irradians irradians, different-colored orange, purple and white lines were established by two mating methods of self-fertilization and mass spawning at a commercial scallop hatchery in spring, 2002. And then larval growth and survival of different lines was compared to test whether there is a relationship between shell color and growth and survival at early developmental stage. Both growth and survival have no significant differences among different experimental larvae of self-fertilization or mass spawning. Results are as following in the order of orange, purple and white shell stock. For the self-fertilization, growth rates of larvae were 6.174, 6.412, and 6.599 μm/d, respectively. Survival rates of larvae at Day 3 were 74.41%, 76.86%, and 82.05%; Day 6 were 49.14%, 65.63%, and 52.79%; and Day 9 were 25.06%, 20.80%, and 26.47%, respectively. For the mass spawning, the growth rates were 7.836, 7.941, and 7.878 μm/d, respectively. Survival rates at Day 3 were 93.05%, 91.95%, and 92.50%; Day 6 were 79.17%, 78.05%, and 82.50%; and Day 9 were 34.72%, 36.67%, and 38.33%, respectively. The absence of any relationship between shell color and growth and survival at the larval stage may be resulted from their common genetic basis.
文摘During the First Chinese Antarctic Expedition zooplankton samples were collected at each of the oceanography stations in the waters around South Sheltland Islands (S. S. Is.) and in the northern part of the Bellinshausen Sea from 20 January to 12 February, 1985 by vertical tows of an 80 cm diameter conical net from 200 m to surface. Two deep tows with a closing net. were performed in slope water north of S.S. Is, and in the basin of Bransfield Strait. Eggs and larvae of Euphatisia superba Dana in zooplankton samples were identified and counted.There were four records of eggs from 27 stations. Most catches were of small number and restricted to within the nearshore area south of S.S Is.The largest number (1500/1000 cubic meters )was found in the outer side of Smith Island.No Nauplius was found . The earliest stage we found 【was Metanauplius , in two deep tows. The distribution of Calyptopis MI and Furcili I-III were quite similar. They were found mainly in three areas: 1 ) nearshore water along the
基金Supported by the National High Technology Research and Development Program of China(863 Program)(No.2006AA10A411)Shandong Agriculture Seed Stock Projects
文摘In laboratory conditions,effects of rearing temperature and stocking density were examined on hatching of fertilized egg and growth of auricularia larvae of Apostichopus japonicus respectively.Data series like larval length and density,metamorphic time,and survival rate of the larvae were recorded.Statistics showed that for A.japonicus,survival rate(from fertilized egg to late auricularia) decreased significantly with the increasing rearing temperature(P<0.05).At different temperatures SGR was statistically significant as well(P<0.05) from day 1,and maximal SGR was found on day 9 at 24℃(159.26±3.28).This study clearly indicated that at low temperature(<24℃),metamorphic rate was remarkably higher than at higher temperature(>26℃).Hatching rate was significantly different between 0.2-5 ind./ml groups and 20-50 ind./ml groups.Rearing larvae at the higher density had the smaller maximal-length,whereas needed longer time to complete metamorphosis.This study suggested that 21℃ and 0.4 ind./ml can be used as the most suitable rearing temperature and stocking density for large-scale artificial breeding of A.japonicus's larvae.