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Study on Species Diversity of Macrofungi Belonging to the Phylum Basidiomycota in Son Tra Nature Reserve, Da Nang

Tran Thi Phu, Do Hong Hanh, Nguyen Thanh Trung

Received: 03-10-2023 / Accepted: 25-12-2023
This study was conducted to understand the diversity of species composition of macrofungi belonging to the phylum Basidiomycota in Son Tra Nature Reserve, Da Nang city by performing a line transect survey in 3 sub-areas divided into 15 different areas. Macrofungi specimens were collected at altitudes between 300 and 690 m above sea level. Among the specimens collected, we have identified 110 taxa belonging to 42 genera, 23 families, 10 orders, and 3 classes of the phylum Basidiomycota. Among them, species such as Microporus xanthopusand Stereum hirsutumare encountered more frequent during the sampling process. The life-styles of Basidiomycota macrofungi in Son Tra were either saprophytic, parasitic or symbiotic. The classification revealed that they can be divided into medicinal group, edible group, or group containing decomposers of organic matter to create humus for the soil. However, some species e also belonged to poisonous group.
Pathological Characteristics of the DogsCaused by CareVirus (CDV-768)

Nguyen Thi Lan, Bounheuang SIHOUNGVANH, Nguyen Thi Yen, Nguyen Huu Nam

Received: 20-10-2014 / Accepted: 29-11-2014
Canine distemper (CD)is an acute infectious disease caused by virusin dogs. Results of infecting virus strain Care (CDV-768) for three Berger doghybrids at2 months of age adose 106TCID50/25µlthrough the eyes, mouth,and nebulizationshowed thatinfected dogs showedsymptoms of moodiness, fatigue, appetite loss, fever, vomiting, diarrhea, and bloody diarrhea with sketchy notes on the skin, thickening/keratinizing of the soles of the feet. The macroscopic pathological lesions were found mainly in the lungs (pulmonary sectional epidemic, lung incarnate), intestinal hyperemia phenomena, hemorrhage, brain hemorrhage, swollen lymph nodes, liver degeneration, and swollen gallbladder. The microscopicpathological signs includedred blood cells inside alveoli, alveolar walls rupture, parenchymal cell degeneration, torn crushed villi,and inflammatory cell infiltration in the brain. Virus concentrated mainly in the lungs, lymph nodesandintestines. The experimental results showedthat virus strain Care (CDV-768)was highly virulentand potentially pathogenic for dogs.
Application of Ultrasound Method for Diagnosis of Canine Pyometritis in Hanoi and ItsTreatment

Su Thanh Long, Tran Le Thu Hang

Received: 20-06-2014 / Accepted: 30-08-2014
People’s living standard nowadays are being improved, hence, the number of people raising a pet increase dramatically. Together with cultural exchange and social and economic improvement, foreigners coming to Vietnam are increasing in number. They come to Vietnam for work or study and most of them brought their pet with. The risk of disease stemming from dog is related to dog number. Facing this reality,pet clinic units are increasing in number with modern equipment to accurately diagnose canine diseases. Ultrasound method was applied for diagnosis, especially, in case of dog pyometritis. By this method, the detecting rate of the disease was higher than clinical examination (P<0.05). The pyometritis rate in local dog breeds was lower than exotic breeds (P<0.05). The older dogs and non pregnancy dogs exhibited higher risk of carrying pyometritis than normal dogs. The recovering rate was 88.88% by surgical method and was higher than conservation treatment (65.21%; P<0.05).
Study on Identification and Culture Conditionfor Biosynthesis of Laccase by Trametes polyzona TĐ16

Nguyen Thi Hong Lien, Tran Thi Huong, Nguyen Van Hieu, Dang Thi Nhung, Phan Thi Hong Thao

Received: 18-08-2023 / Accepted: 26-12-2023
White-rot fungi are capble of degrading wood lignin by extracellular lignin modifying enzyme system, in which laccase plays an important role in ligninolysis and is widely used in some industries. This study was carried out with the objective of identifying the white rot fungus TD16 and selected suitable conditions for the biosynthesis of laccase to apply in the biopulping. The strain TD16 was studied for biological characteristics and sequence of the ITS - rDNA gene analyzed. The fruiting bodies have a scalloped shape and the edges are smooth. The upper surface of fruiting bodies is dark brown with concentric circular veins. The hymenium layer is white-brown and rough. On MEA medium, the colonies of TD16 fungal strain are fluffy, snow white, and evenly circular. The strain TD16 has a relatively fast growth rate and can produce extracellular enzymes. The strain TD16 was identified as Trametes polyzonaand named as Trametes polyzonaTD16. The optimal culture conditions for enhanced laccase biosynthesis were investigated. Trametes polyzonaTĐ16 showed the highest laccase activity of upto 8.135 U/ml on MT2 medium containing 0.0625mM CuSO4after 7 days of fermentation at 37ºC and pH of 5.0.
Functional Roleof Mould Strains in Production of Rice Wine

Nguyen Ngoc Hoa, Dang Xuan Nghiem

Received: 07-03-2012 / Accepted: 17-05-2012
This investigation on the possible role of mould in production of traditional rice wine was carried out with the 4 candidate mould strains which were selected from 21 mould strains isolated from traditional rice wine starters and traditional soysauce starters. The 4 mould strains were preliminarily identified and named as M3 (Rhizopus spp.), M10 (Rhizopus spp.), M16 (Aspergillus oryzae), and M18 (Endomycopsisfibuliger). M10, M16 and M18 strains expressed very strong extracellular enzyme activities (amylase, protease, cellulase), while M3 strain had weak extracellular protease and cellulase activity and no extracellular amylase. Noteably, the yield of rice wine of the traditional alcoholic fermentation was not increased when large amounts of the biomass of the 4 isolated mould strains were added. There was a strong correlation between the pH of fermention liquid and the final yield of wine. The lower the pH of fermentation liquid was, the lower the yield of wine. Moreover, all 4 mould strains were determined to have no role in the formation of aldehyde, methanol and higher alcohol in rice wine products.
Some Physiological Parameters in Sevoflurane-Anesthetized DogsDuring Sterilization

Hoang Thi Ngoc Huyen, Hoang Phuong Nguyen

Received: 20-12-2022 / Accepted: 29-06-2023
This study aimed to examine some physiological parameters including heart rate, respiratory rate, body temperature, blood pressure, and oxygen saturation in dogs that were anesthetized with sevoflurane for sterilization and to examine the associations between these parameters at different times of anesthesia. Thirty-four (34) dogs with body weights between 1.7 and 25kg were pre-anesthetized with zolazepam, tiletamine, medetomidine hydrochloride, and butorphanol, and then they were maintained with sevoflurane. Physiological parameters were recorded at different times during anesthesia. During surgical anesthesia, the heart rates and body temperatures of most dogs were in the physiological range. The respiratory rate, blood pressure, and oxygen saturation varied widely. At the time of the Sevoflurane connection, the heart rate was directly proportional to the breathing rate, and systolic blood pressure was directly proportional to temperature and heart rate. However, these associations were no longer present at 30 minutes and 60 minutes after the sevoflurane connection. At 60 minutes, oxygen saturation was inversely proportional to diastolic though this association was not present at the time of the Sevoflurane connection and at 30 minutes. The results show that sevoflurane maintenance of anesthesia in dogs was safe. Because physiological parameters could vary widely within each dog and during anesthesia, all dogs have to be monitored carefully throughout the surgical process to handle complications that might occur. On the other hand, Sevofulrane might have effects at different degrees on different physiological parameters and this potential characteristic should be investigated in future research.
Several Research Approaches on Governancein Agricultural Cooperativesin the World and Applicability in Vietnam– A review

Tran The Cuong, Nguyen Huu Nhuan, Tran Dinh Thao

Received: 11-04-2023 / Accepted: 21-06-2023
Research on governance in agricultural cooperatives in Vietnam is not yet popular while the agricultural cooperative model is facing the requirement of changing governance to ensure the interests of cooperative members as well as other stakeholders to promote development. By synthesizing studies on reputable data systems, the article presents an overview on concepts and mainstream theories applied in research and models of governance in agricultural cooperatives, then discuss the possibility of applying relevant theories to appropriate types of cooperatives in Vietnam.
Satisfaction withTBR225 Rice Variety ofFarm Households in Hanoi City

Chu Thi Kim Loan, Tran Minh Chau

Received: 16-02-2022 / Accepted: 18-04-2023
Theobjective of the paper was to analyze the satisfaction level of farmhouseholds in Hanoi citywith TBR225 rice variety. Theprimary data were collected from a survey of 300 farmhouseholds in 2022. Thestudy imployed analytical methodsof descriptive statistics, T-test and ANOVA. The surveyresultsshowsthat the satisfaction of thesurveyed farmers with TBR225varietywas veryhigh (4.34/5 points). Many factors contributingto the general satisfaction of thefarmers wereassessed at highscoresof 3.41-4.24,especially the indicators of thevariety quality. Some indicators had average scores thatshould be improved suchasdegradability orreuse of thepackages (3.01), thepromotional programs (3.12), and stability of theprice(2.88). The test shows that there wassignificantdifference in the average satisfaction scoresbetween groups of thefarmhouseholds. Specifically, the group of farmers in Thanh Oaidistrict,the households with more than two-thirds of the rice cultivated area under TBR225 variety, or adopting TBR225 variety cultivationfrom two to three crops, had a higher average score than the remaininggroup.
Agricultural Commercialisation and Multidimensional Poverty: AReview

Nguyen Tien Dung, Le Thi Hoa Sen, Hoang Gia Hung, Tran Thanh Duc, Hoang Thi Hong Que, Phan Viet Toan, Le Viet Linh, Hoang Dung Ha, Nguyen Van Chung, Le Van Nam, Le Chi Hung Cuong, Truong Thi Hang

Received: 14-11-2022 / Accepted: 27-03-2023
This paperaimedto review agricultural commercialisation and multidimensional poverty concepts and to propose the theoretical framework for their relationship in agriculture-based developing countries. Agricultural commercialisation is the transition from subsistence production to market-oriented production. Multidimensional poverty takes into accountthe deprivation of people, including income andbasicsocial deprivation.The proposed theoretical framework on the relationship between agricultural commercialisation and multidimensional poverty includes four components. The agricultural commercialisation process is a central position reflectingsubsistence, semi-commercial and commercialagricultural production system of farmhouseholds.The input factors include driver factors and determinants, which keep the roles in pushing the agricultural commercialisation process.The final component in the framework is multidimensional poverty, an outcome of agricultural commercialisation.The theoretical framework is essential for further studies on multidimensional poverty reduction based on agricultural commercialisation in Vietnam.
Effects of Combining Soil and Foliar Fertilization on Growth, Developmentand Yield ofEggplant

Thieu Thi Phong Thu, Tran Thi Thiem, Phung Xe Pa

Received: 06-12-2022 / Accepted: 27-03-2023
The experiment aimed to determine the suitable types of organic fertilizer for the growth, development and yield of eggplant in Gia Lam, HaNoi.Atwo-factor experiment was laid out in randomized complete block design comprising 8treatments with three replications. The first factor wassoil fertilization withP1 - Chicken manure, P2 - Minori fertilizer, P3 - Inorganic fertilizerandP4 - Vermicompost. The second factor wasfoliar organic fertilization with C1 - O-MIC and C2 - HB101 (plant vitalizer). Research results showed that vermicompost exhibitedthe best effectson the growth and yield of eggplant. Foliar application of HB101 brought better effectson the growth and yield of eggplant compared to application of O-MIC. Combined use of vermicompost and HB101 foliar vitalizer gave the highest eggplant yield of 14.05 tons/ha, 2.89 tons/ha higher than the yield in combination ofinorganic fertilizerandO-MIC and 2.39 tons/ha higher than the yield inthe combination ofinorganic fertilizerand HB101.
High-Tech CantaloupeCultivationin Tay Ninh Province -Current Situation and Solutions

Vong Thinh Nam

Received: 07-03-2022 / Accepted: 02-03-2023
This research aimed to understand the current situation of high -tech cantaloupe cultivation in recent years, find out existing problems so as to provide solutions which develop high -tech cantaloupe cultivation in Tay Ninh province in the future. Secondary data were collected from documents of local reports and relevant previous researches. Primary data were gathered through survey of 20 households practicing high tech cantaloupe cultivation in Tay Ninh province. Results of the research show that areas for growing cantaloupe were concentrated in urban areas where cultivated land was limited and the growers were not aware of high-tech cultivation. The packaging and preservation were not done promptly at harvest which may affect quality of product. The households did not actively access to stable consumption channel. Some solutions to develop high-tech cantaloupe cultivation in Tay Ninh province -a strong agricultural province - were recommended.
Effect of Temperature on the Development of Spodoptera frugiperda(J. E. Smith) (Lepidoptera: Noctuidae)

Tran Thi Thu Phuong, Giang Kim Long, Nguyen Thanh Hai, Ho Thi Thu Giang

Received: 05-09-2022 / Accepted: 20-12-2022
The fall armyworm Spodoptera frugiperda(J. E. Smith) (Lepidoptera: Noctuidae) is a serious polyphagous insect pest native to the Americas. The objective of the present study was to determine the effect of temperature on developmental time and oviposition of fall armyworm in Vietnam. Fall armyworm was reared individually in incubators at different temperatures (20, 25, 27.5, 30, and 33C), 75-85% RH, and12L:12D photoperiod with maize leaves (variety HN88) at 3-5 leaf stage as food. The life cycle of the fall armyworm at temperatures of 20, 25, 27.5, 30 and 33C was 50.56, 36.92, 31.91, 24.28 and 22.28 days, respectively. The total number of eggs laid by a female at temperatures 20, 25, 27.5, 30 and 33C was 1,119;1,020;1,152;1,168 and 778 eggs, respectively. The lower threshold temperature for development of egg, larvae, and pupae was 11.14C, 12.47C, and 13.59C, respectively. The thermal constant (K) for egg, larvae and pupae development was 42.7, 200.71 and 129.65 degree day, respectively. The degree-day required for egg-to-adult development of fall armyworm was 383.67.
Effects of some Fermentation Conditions of Aspergillus oryzae T6 on the Biosynthesis of -Glucosidase inhibitors in the Production of Health Foods for People with High Blood Glucose and Overweight

Nguyen Duc Tien, Nguyen Thi Huyen

Received: 05-10-2022 / Accepted: 20-12-2022
This study evaluated the influence of some fermentation conditions on the biosynthesis of α-glucosidase inhibitors (AGIs) of AspergillusoryzaeT6 (A. oryzae T6) cultured on semi-solid medium from black beans in the production of health-protective foods for people with high blood glucose and overweight. By determining the inhibitory activity of α-glucosidas the results showed that the biosynthesis of AGIs on semi-solid medium from black beans (Vigna cylindrica Skeels) gave the best effect in terms of the thickness of the fermentation medium block (24cm). The periodic agitation of the semi-solid medium from black beans during fermentation was every 12 hours; humidity of semi-solid medium from black beans for fermentation was 55% and fermentation time was 56 hours. The resulting AGIs products with IC50of 0.202 ± 0.006 mg/ml were applied to food production to help stabilize blood glucose in people with high blood sugar and overweight.
Isolation and Selection of Lactic Acid Bacteria for Probiotic Beverage Production from Ginger

Vu Quynh Huong, Vu Thi Yen, Nguyen Thi Thanh Thuy

Received: 28-09-2022 / Accepted: 20-12-2022
Lactic acid bacteria play an important role in the production of fermentedfoods. This study aimed to isolate and select lactic acid bacteria strains from fermented products for application in the production of ginger-based probiotic drinks. Fourty sixstrains of bacteria were isolated. The isolates producedcolonies with 1.0 to 1.5mm in diameter, mainly round, glossy, milky white, and floating pellicle in liquid culture. Six gram-positive, catalase-negativestrains withrod orspherical shaped cellswere pre-selected. Identification by MALDI-TOF revealedthat theybelongto 4 speciesof Enterococcus faecium, Enterococcus casseliflavus, Lactobacillus fermentumand Lactobacillus plantarum. Furtherstudy was conducted for the strain L.plantarumSM1.3. Itwas tolerantto acid(pH 1.0-3.0)and 0.3%bile salts,and ableto produce amylase, protease, and cellulase. This strain inhibited two tested bacteria,E. coliand Salmonellasp.Gene alignment results indicated that the strain SM1.2 belongedto Limosilactobacillus fermentumspecies and strain SM1.3 namedLactiplantibacillus plantarum.Ginger-based probiotic drink usingL. plantarumSM1.3 has good sensory quality andbacterial density and can be stored up to 5 days at 4C.
Technical Efficiency in Pig Fattening at Household Level in Hanoi

Le Thi Thu Huong, Luu Van Duy

Received: 08-07-2022 / Accepted: 15-08-2022
Small-scale pig holders in Vietnam arefacing variousdifficulties because ofincreasing input costs and fierce competition withlarge-scale livestock farming. Therefore, finding ways to improve technical efficiency in pig production can help the farmers deal with this problem. To measure technical efficiency and analyze the factors affecting the technical efficiency in fattening pigsat household levelin Hanoi, the presentstudy useddata envelope analysis (DEA) approach and Tobit regression. The research results showedthat the technical efficiency of the households was 67.3% on averge, indicatingthat the households can reduce 32.7% of the inputs without affecting the output. To improve technical efficiency, in the short term, the households should use a combination of industrial feed and agricultural by-products, speed up the raising time, and adjust the density of pigs in the barn. In the long term, the households should adjust the production scale to improve technical efficiency.
Biological Characterization of Streptomycessp. VNUA30 Strain with Antagonistic Activity Against Pathogenic Fungi CausingDisease on some Plants

Nguyen Thi Thanh Mai, Nguyen Thanh Hai, Nguyen Thi Thu, Tran Thi Dao, Nguyen Xuan Canh

Received: 04-05-2022 / Accepted: 05-07-2022
Diseases caused by pathogenic fungi account for 80% of plant diseases resulting in a global crop yieldreduction. The use of chemical fungicides for the control of fungal diseases causes environmental pollution and affects human health. Biocontrol using actinomycetes having antifungal activity was reported to be effective and biosafe. This studyfound that actinomycete strain VNUA30 exhibited a broad-spectrum antifungal activity against five plant pathogenic fungi, i.e. Colletotrichum gloeosporioides, Fusarium oxysporumf.sp. cubense(FocTR4), Corynespora casiicola, Sclerotium rolfsii, and Diaporthe sp. with inhibition rate of 62.50%; 52.58%; 72.22%; 57.77%; and 95.37%, respectively. Biological studies showed that strain VNUA30 was able to produce melanoid pigment, siderophore, H2S and IAA, assimilate citrate, reduce nitrate, liquefy gelatin, degrade urea and produce extracellular enzymes chitinase, cellulase, xylanase, protease, and pectinase. Combining the morphological and biochemical characteristics with the 16S rRNA sequence analysis, this strain was identified as Streptomyces deccanensis VNUA30. The results confirmed that actinomycete strain VNUA30 is a potential strain as bio-control agent for fungal diseases on plants with high efficiency.
Effects of Wood Vinegar in Crop Cultivation: A Review

Do Thi Huong, Phan Thi Thuy, Nguyen Thi Ai Nghia

Received: 27-09-2021 / Accepted: 05-04-2022
Wood vinegar is produced fromagricultural and forestry byproducts pyrolysis such as waste from woodandbamboo, rice straw, husks, sugarcane bagasse and corn-cob. Wood vinegar consistsof more than 200 water-soluble chemicalcompounds, 80-90%water and 10-20% organic chemicalcompounds: organicacid, alkane, phenolic, alcohol and ester. Thus, wood vinegar has a powerful antioxidant and antimicrobial activity as well as anti-inflammatory agent, anti-fungal drug, pest control and natural plant growth promotion. This review article sums up the rolesof wood vinegar in crop cultivation such as promotingcropgrowth andyield, enhancing the use efficiency of chemical fertilizersand pesticides, stimulating germination, improvingsoil health and manure quality,and eradicating weed.Therefore, wood vinegar can be considered to be a potential material for sustainable agricultural development in Vietnam.
Ecotourism Development in XuanThuy National Park

Pham Thi Thanh Thuy, Do Kim Chung

Received: 02-11-2021 / Accepted: 27-05-2022
Ecotourism is growing rapidly and actively contributes to the improvement ofthe livelihoods of local people, tourists' understanding of biodiversity and protectionof natural resources. The article aimedatpointingout the current status of ecotourism development activities and thereby proposing solutions to improve the efficiency of ecotourism activities in Xuan Thuy National Park. In addition to secondary information, primary data were collected from 110 tourists, 35 households participating in providing ecotourism services, 2 management staff of Xuan Thuy National Park, and 12 managers at district and commune level. The research results show that ecotourism development has had an unstable growth over the past time and was facing many difficulties and challenges such as poor infrastructure for ecotourism, low level of human resources, etc. The tourism expertise wasnot high as well as tourism products werelimited, and lackedcohesion with tour operators and routes in attracting visitors. The solutions to promote ecotourism in Xuan Thuy National Park are suggested as follows: organizing and promoting ecotourism development; improvingthe efficiency of management and protection of natural resources and the environment; investingin infrastructure for eco-tourism in Giao Thuy district.
Thiết kế và chế tạo mô hình chuyển động năng thu được từ chuyển độngcủa xe thành điện năng

Nguyen Van Dieu, Ngo Tri Duong, Bui Quoc Huy

Received: 14-10-2024 / Accepted: 30-05-2022 / Published: 29-05-2024
Bài báo này đề xuất một mô hình thu năng lượng động học được lắp đặt dưới gờ giảm tốc để thu năng lượng bị lãng phí do các phương tiện đi qua gờ giảm tốc. Mô hình bao gồm ba phần chính: hệ thống truyền động - bơm - hệ thống lưu trữ, mô-đun máy phát điện, mô-đun điều khiển. Hoạt động như một đầu vào năng lượng, hệ thống truyền động - bơm thu năng lượng động năng để tạo ra khí nén. Sau đó, hệ thống lưu trữ sẽ lưu trữ lượng không khí này để nó sẵn sàng xả khí tới hệ thống máy phát điện. Khi khí nén được xả vào mô-đun máy phát điện, mô-đun này sẽ tạo ra năng lượng điện có thể được sạc cho ắcquy. Mô-đun điều khiển có thể tự động giám sát và điều chỉnh lượng khí nén cũng như năng lượng trong ắcquy. Các thử nghiệm được đưa ra cho thấy hệ thống có khả năng tích trữ một lượng khí nén dưới 50psi. Năng lượng này cho phép tạo ra điện năng một chiều 14,8VDC để nạp vào ắcquy 12VDC. Kết quả ban đầu cho phép tiến hành những nghiên cứu sâu hơn về một nguồn năng lượng mới trong tương lai.
DOI: https://doi.org/10.1234/2c2fdq38
Genetic Identification of Target Mutationsin OsSWEET14 Promoter-edited TBR225 Rice Lines

Tran Lan Dai, Pham Thu Hang, Cao Le Quyen, Pham Thi Van, Pham Xuan Hoi, Nguyen Duy Phuong

Received: 29-11-2021 / Accepted: 05-04-2022
Understanding host-pathogen interactions is key in breeding disease-resistant crops, including bacterial leaf blight. As a key virulence strategy to cause bacterial leaf blight, Xanthomonas oryzae pv.oryzae(Xoo) secretes transcription activator-like effectors (TALEs) to control the expression of host target genes through binding to the effector-binding elements (EBEs) located on the promoter regions. Precise mutagenesis at the TALE-interaction sites on the host genes by using gene editing tools such as clustered regularly interspaced short palindromic repeats/CRISPR-associated protein-9 nuclease (CRSIPR/Cas9) has been seen as a promising way to improve BLB resistance ofrice cultivars. In a previous study, we generated some transgenic TBR225 rice lines containing a single copy of CRISPR/Cas9 expression construct for editing AvrXa7/Tal5EBE on the promoter OsSWEET14. In this study, we continued to evaluate genotype and phenotype of T1edited TBR225 lines to determinethe genetic stability and phenotypic effective of the CRISPR/Cas9-induced OsSWEET14mutations. The genotypic analysis showed that 65%of transgenic TBR225 plants harbored the targeted OsSWEET14mutation, including nucleotide (Nu) insertion and deletion. The OsSWEET14mutations were stably inherited to the next generation with an expected segregation ratio consistent with Mendelian segregation (1:2:1). The preliminary phenotypic analysis suggested that the mutation of OsSWEET14promoter did not affect the growth and yield of gene-edited rice plants. Some T1TBR225 lines showed the resistance to Xoo isolate VXO_11 in the leaf-clipping experiment. The obtained results are a premise for development of the BLB-resistant TBR225 rice variety in the future.
Application of SCP Modelling in the Development of Stable Market for Cobia Fish in Nghia Hung District Nam Dinh Province

Bui Thi Mai Linh, Nguyen Thi Thu Trang, Nguyen Thi Kim Oanh, Doan Thi Ngoc Thuy

Received: 28-09-2021 / Accepted: 01-03-2022
The present research analyzed the impact of the structure and the conduct on the market efficiency to develop a stable market for cobia fish farming households in Nghia Hung district, Nam Dinh province. The study used 217 samples with direct interview method and the data collected were analyzed by structural equation modelling (SEM) to evaluate the strength of the relationship between the structure, the conduct and the market efficiency. Research results showed that structural factors and market conduct positively affected market efficiency, but the cost factor exerted no influence on the fisheries policy. The findings showed that the competitive advantage factor had the strongest impact on fisheries policy factor (0.414), followed by and material input (0.345). The industry competition factor had the biggest influence on quality assurance factor (0.145) while the quality assurance factor (0.353) exerted positive impact on improving market efficiency and developing a stable market. Some solutions to promote these factors were proposed.
Current Status of Environmental Cost Management Accounting at Animal Domestic Feed Production Enterprises in Vietnam

Nguyen Dang Hoc, Bui Thi Khanh Hoa

Received: 23-09-2021 / Accepted: 01-03-2022
This study aimed to reflect the performance of applying environmental cost management accounting (ECMA) at domestic animal feed production enterprises in Vietnam. Descriptive statistics technique was applied to describe the situation and implementation level of ECMA in 102 surveyed enterprises. Anova analysis was also used to compare and test the difference in the level of implementation of ECMA among enterprises which had different production scale. The research results showed that the environmental costs identified in domestic animal feed production enterprises included the cost of waste treatment, the cost of environmental management and prevention, and the cost of non-product output. However, there were very few enterprises that kept track of environmental costs on their own accounts and most of them did not establish norms and separately estimate environmental costs. Especially, none of enterprises had separate environmental costs reports; rather these costs were intergrated in the other expenses reports. Some recommendations animal feed production enterprises to compelete ECMA were proposed.
Nutrient Requirements of Dogs and Cats: AReview

Le Duc Ngoan, Dinh Van Dung

Received: 08-10-2021 / Accepted: 21-01-2022
Dogs and cats are two types of domesticated animals that have been close to humans since ancient times. They are kept for house keeping, hunting, and entertainment (racing) purposes and are increasingly popular as pets. Viet Nam currently has more than 5 million families raising more than 7.5 million cats and dogs, equal to the number of largeruminants in the country. As pets, so their owners pay more attention to optimize nutrients to ensure good health (ideal body condition, neither obese nor rather thin) rather than maximize nutrients. The objective of this paper was to review the basic nutrient requirements of cats and dogs based on recommendations of NRC (2006), AAFCO (2014) and FEDIAF (2017) and some other studies.Dogs and cats are both carnivores, their energy requirements are higher than that of other livestock (4,000 kcal metabolizable energy/kg feed).The crudeprotein requirements of dogs are lower (18-23%) than those of cats (20-33%), but these are also higher than those of cattle and pigsor poultry, and the requirement for some nutrients is also very different from that of traditional livestock.
Study on Artificial Diets for Rearing Predatory Mite Amblyseius swirskiiAthias-Henriot (Acari: Phytoseiidae)

Duong Thi Nga, Nguyen Duc Tung

Received: 05-08-2021 / Accepted: 21-01-2022
This study aimed to find out the most suitable artificial diets for rearing predatory mite Amblyseius swirskii Athias-Henriot. The experiment was conducted according to individual rearing method in an incubator at 27℃with four artificial diets, viz. TA1 as basic diet (containing sucrose, yeast extract, egg yolk powder, vitamins mix); TA2, basic diet supplemented with 20% black soldier fly pupal powder; TA3 and TA4, basic diet supplemented with 20% decapsulated and non-decapsulated TA4 of dry cysts of Artemia franciscana, respectively. The results showed that females of A. swirskii fed on TA2 and TA3 had the shortest life cycle (7.68 and 7.88 days, respectively), followed by those fed on TA4 (8.11 days) and the longest was those fed on TA1 (8.68 days).The total number of eggs laid by the females rearing on TA2, TA3 or TA4 was significantly higher than that of TA1. The intrinsic rate of increase (rm) of the females fed on TA2 (0.182), TA3 (0.176) and TA4 (0.174) were significantly higher than those fed on TA1 (0.151). In conclusion, the artificial diets TA2, TA3 and TA4 can be used in mass rearing A.swirskii, and can also be used as supplemental diets for supporting the mite population on crops in the absence or lack of prey.
Bacillus sp. Isolated from Goose Grass (Eleusine indica) Enhances the Removal Efficiency of Ammonium in Shrimp Aquaculture

Do Quang Trung, Tran Thi Tuyet Thu, Luu The Anh

Received: 03-08-2021 / Accepted: 21-01-2022
Treatment of aquaculture wastewater by biological method is being more attractive to the scientists. This study aimed to screen the salt-tolerant and ammonia-oxidizing Bacillusendophytic bacteria having potential to reduce ammonium levels in shrimp aquaculture wastewater. In this study, eight Bacillusstrains were screened from endophytic bacteria isolated from gooose grass. Among these strains, two strains, MT50 and MT51 showed the highest efficiency for ammonium removal (80.36 and 82.24%, respectively). They optimally grew at pH of 7 and in highly salty condition (4% NaCl). Investigation in laboratory conditions for their ability in improving shrimp aquaculture wastewater showed that both Bacillusstrains had ammonium removal from 72.25 and 78.85% at day 7th. Notably, strain MT50 in combination with unsterilized shrimp-wastewater presented the highest ammonium removal efficiency (79.91%) with 1% cell suspension at day 4th. The results also showed the nitrite and nitrate production in all experiments and these compounds were removed by the selected Bacillusspecies. Results suggested that tưo Bacillussp. isolated might be used as heterotrophic nitrification-aerobic denitrification species.

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