Vol. 16 No. 12 (2018)

Anthracnose caused by Colletotrichumspp. is one of the most destructive diseases of chili in Vietnam and worldwide. Identifying Colletotrichumspecies that cause anthracnosebased on morphological characteristics often causes confusion. The objective of the study was to design specific primer pairs for rapid and accurate diagnosis of Colletotrichumfungus causing anthracnose by PCR(polymerase chain reaction). In the study, based on the Internal TranscribedSpacer (ITS) region and the intergenic region of apn2 and MAT1-2-1genes (ApMat) four specific primer pairs were designed. Four species,i.e.C. truncatum, C. fructicola, C. gloeosporioides sensu strictoandC. siamensethat cause chili anthracnose in the Red River Delta and some other provinceswere detected.The study also showed that a modified rapid extraction protocol using NaOH was highly effective to prepare DNA samples from Colletotrichumcultures for PCR reaction. PCR analyses using the newly designed specific primers on 52 chili Colletotrichumisolates collected from 13 provinces, mainly the Red River Delta, revealedC. siamenseas the most abundant species (51.9%of total isolates), followed by C. fructicola(21.2%), C. truncatum(15.4%), and C. gloeosporioidessensu stricto (9.6%).

The study was conducted to evaluate the conformationalcharacteristics and production performance of Hon Chu chicken, a major local chicken of Lao PDR. The assessment surveys were conducted in some households in the 3 neighboring villages of Luang Prabang. The experiments to evaluate conformation, performances of reproduction and production were conducted at Northern Luang Prabang Agriculture and Forestry College, Lao PDR. Results showed that Hon Chu chickens had small stature and variable body color patterns. Under free range conditions at households, the male and female body weight at 20 weeks of age was 780 and 670 g, respectively. The first laying age was over 7 months of age and egg production was 62 eggs/layer/year. Underconfinement conditions and mixed feeding, at 24 weeks of age, cock and hen weight was 2,171 and 1,858 g, respectively. At 30 weeks of age, the meat proportion was 71%, the ratio of the thigh meat was higher than the breast. The first laying age was 23rdweek with egg yield of 25 eggs in 13 laying weeks but small eggs (44 g), and thick eggshell.

The objective of this study was to evaluatethe species composition and stock of aquatic products in the West Lake and to recommend management solutions for conservation and sustainable development of fisheries resources. By the general world classification method and domestic standards as well as reserve assessment, the results indicated aserious decline in composition of fish and molluscs, with 21 species of fishes and 3 species of molluscs being recorded. Bottom stocking biomass and mollusc stocking density were low (10.64 g/m2). The composition of fish species was not suitable withtilapia dominated, accounting for 88.87% of the total biomass. The fish farming and other natural fish species were very low. The reserve biomas was low, only 243-270 tonnes.

Gross and histological structures of the salt glands of the sea duck 15 (VB15) and the F1(VB15 x mallards) ducklingswere investigated in this study. The ducks hadbilateral crescent salt glands under the skin in the supraorbital depression of the frontal bone. The measurements of the gland length, width and weight showed that the gland development wasfaster from post-hatching to 6 weeks of age. There were no differences of the three values among three duck groups raised in fresh water. The salt glandsof VB15 raised in sea water had higher weight than that of the counterparts in fresh water. The glands of VB15 consistedof concentric polygonal lobes arranged in rows and separated by interlobular connective tissuesthat contain vasculature system. Each lobe hadbranched striated secretory tubules lining with single layer of cuboidal cells. Connective tissue was underneath the cuboidal cellepithelia. Thebranchedductsopenedinto the central canal that drain in a main duct leads to the anterior of the nasal cavity. This is the first study on salt glands of Vietnam marine animals, especially of VB15breedand can be considered as the basisfor further studies on age-dependent functions of the salt glands and theoptimal age of VB15 for shifting from fresh water to salty water as well as appropriate salinity for VB15.

The aim of this study was to determine the serotypes of Haemophilus parasuisstrains isolated from suspected pig cases of glasser disease. A total of 205 specimens including nasal,trachea, joint fluids, heart and lung collected from 41 suspected pigs inThanh Hoa, Hung Yen and Ha Nam province were used for bacterial isolation and identification. The isolates (22 isolatesin total)ofH. parasuisfrom pigs suspected of being infected withH. parasuisshowedthe major characteristics of small, transparent, and non-hemolytic colonies,gram negative, pleomorphic rod from short to long bacilli,catalase, oxidaseandV factor positive, indole and urease negative, and capable of fermentatingglucose, galactose and fructose, and unable to grow on MacConkey agar. Theseisolates were confirmed by specific PCR asH. parasuis. In the present study, for the first time, we reportedthe application of multiplex PCR assay for serotypedetermination ofH. parasuisisolates from the field in Vietnam.mPCRresults showed variable distributions in the serotypesofH. parasuisisolated from the field. Remarkably,serotypes4, 5 and 1 were the most prevalent with 25%, 25% and15%, respectively, followed by serotypes13 and 2 with 5%, and non-typable serotypewith 20%.

At present, for the rapid drying of poultry manure, high price drying mixer must beimported. Thus, design and manufacture of a small size dryer are required to produce organic fertilizer from poultry manure and to reduce poultry manure processing time, improve the quality of organic fertilizer, reduce investment and production costs, and reduce environmental pollution. Combining theoretical and experimental research and using graphic design software such as SolidWorks, AutoCAD, and Inventor were employed to select the structure, operating principles and specification of technical parameters and to test working performance of themixer. Drying machine with the capacity of 500kg/batch was of lightweight structure and easy to manufacture and install, operate and clean. The machine was of low cost, suitable for processing poultry manure into organic/microbial fertilizers and for drying various types of livestock wastes. In addition to the poultry manure processing, the machine can be used for drying or mixing complete feeds from ground raw materials of naturally-derived or concentrate feeds with locally available ingredients.

A mini-stamping machine model using compressed air was designed on the basis of the existing equipment and technical design softwares combined with the results of calculations. The machine model is intended for use in training andscientific research. Technological parameters of the machine were calculated, determined and selected based on the shape, size and materials of the parts to be manufuctered. Mini stamping machine using compressed air can be fabricated in variable types of parts thanks to the quick, convenient structure and shape change of the forming machine. Based on the design drawings, the parts and part cluster were manufactured and assembled into a complete machine model and applied to the processing of sheet metal forming.

This study aimed to investigatethe effect of soaking temperature on germination and the effect of light exposure conditions and time on the polyphenol content and antioxidant activity of germinated soybean and mungbean seeds. Five soaking temperatures,viz. 25, 30, 35, 40,and 45C,were tested andseeds were germinated under dark and light conditions. Results showed that 30C was optimal for soaking as evidenced bythe highest germination rateandsprout length and weight. Polyphenol contents and antioxidant activities measured by Folin-ciocalteu and DPPH methods, respectively, showed thatpolyphenol content increased over time under both dark and light conditions, in which mung beans increased more significantly. Indark condition, the polyphenol of mung bean rised from 0.5 mg GAE/g DW in the original seeds to 4.9 mg GAE/g DW at 5thday, while this value of soybean increased from 1.0 mg GAE/g DW in the original seeds to 3.4 mg GAE/g DW at 5thday. The antioxidant activity also increased during germiation. The antioxidant activities of mung beans and soybeans were 0.12 and 1.3 mol TE/g DW, respectively, and these increased to 4.8 và 3.2 µmol TE/g DW at 5thdayunder dark condition.Germination resulted in an increase in polyphenol contents and antioxidant activities of the two beans.

The objective of the study was to assess the factors affecting the level of households’participation in forest management, protection and developmentand topropose policy implications forforestmanagement, protection and development in Tra Vinh province. The data used in the study were collected from a questionnaire survey with a total of 191 householdsand analyzed usingthe multiple regression model (OLS) to determine the factors influencing the levelof households’participation forest management, protection and development. Results showedthat positivefactors influencing households’participation wereawareness, income from forest and non-timber forest products, distance from forest to the Commune People's Committee (or commune market), creditaccess, duration of forest protection contract, female household headand ownership of land use right certificate.On the other hand,three variables with negative relationship with the level of households’ participation includedexperiencein aquaculture production,forest management by the contract and income from fishery exploitationin the forest.

In order to clarify the current situation and use of preferential loan, data were collected from 255 students and alumni at Vietnam National University of Agriculture, who had borrowed and not borrowed preferential loans from the Vietnam Social Policy Bank in the period of 2014-2016. Results showed that nearly 67% of students borrowed 4-8 times, of which 30% borrowed in 6 semesters, accounting for the highest proportion of loans. Ninety four percent of students used the loan for tuition fees, living expenses, housing, and materials. Tuition fees accounted for the highest proportion (90%) while living expenses such as lodging, and eating accounted for 44.25%. The average student loans increased but it only met 49% of the cost for education. The study also showed that the loans had a positive impact on students’ education, learning outcomes, extracurricular activities and employment. Based on theses results, three main solutions were proposed: (1) Considering loan grant to non-policy students; (2) Lending with the maximum amount according to the state regulations; (3) Continuingto raise the annual maximum loan amount.

African swine fever (ASF) is a contagious viral hemorrhagic fever, that can kill up to 100% of infected pigs. ASF isoriginally occurred inmanyAfrican countries. Currently, the ASF has spread to central and eastern Europeancountries and China. Since its first report on 19 February 2019to 07April 2019,twenty threeprovinces/cities in the North and Middle of Vietnam have been reportedwith ASF incidenceand tend to spread to southern provinces. Although live-attenuated vaccines and subunit vaccines may serve as promising candidates, the vaccine development against ASF has been hampered by large gaps in knowledge of the biology of ASF virusandits interaction with the hosts or immunity. Strict biosecurity remains the most crucial aspect in the control and spread of ASF between domestic pig farms. In this review, important information on dificulties and prospect for developing ASF vaccine as well as effective experience from other countries were evaluated and discussed. Furthermore, the approp[riate recommendations applied toASF situation in domestic pigs in Vietnam were provided.