Vol. 13 No. 1 (2015)

Two-line hybrid rice has been developing in Vietnam. By 2013, 11 two-line hybrid varieties have been recognized as national varieties. This study aimed to characterize agronomic traits, yield characters and tms genotypes of TGMS lines. In spring season 2013, the TGMS lines showed following performances: 140-163 daysgrowth duration,14-16leaves,62.2-84.6cmin plant height,19.5-25.8 cmin panicle length, short flag leaf, incomplete panicle exsertion, compact architecture, high rateof long filament, long flowering duration (4-10 days),168.8-208.8seed per panicle and, 19.3-26.2 gramin 1000 seed weight. All 16 TGMS lines were genotyped with tms5while 827S line hadboth tms4and tms5 gene.

Tomato is apopularly important vegetable in the world and Vietnam. Assessing genetic diversity and detcetion of genes for disease resistance of the existing germplasm of tomato are usefull for development ofnew varieties with high yield, good qualityand disease resistance. In this study,10 SSR markersand four markers related to TYLCV resistance genes (Ty1, Ty2and Ty3) were usedto analyse genetic diversityand identify the TYLCV genes, respectively, of26 of tomatoes accessions available at food crops research institute. The results showed, that only 5 marker showedpolymorphism.26 accessions were grouped into 5 clusters with similarity coefficients threshold of 0.7 by using NTSYSpc 2.1 software. The information found in this study is very important fornew tomato hybrid breeding programs.Only four of 26 accessions carriedTy1andthe genesTy2 and Ty3 were not detected

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).

Catfish genus SilurusLinneaus, 1758 (family Siluridae, oderSiluriformes) in Vietnam hasbeen identified with2 speciese, i.e.S. asotusLinneaus, 1758 distributed in provinces in Northen Vietnam, Southern China and Northen Laos andS. meridionalisChen, 1977, distributed in Ky Cung river in Lang Son province, Southern China (Guangdong, Guangxii, Sichuan & Hubei provinces). Threenew species were discovered recently S. caobangensissp.n. collected fromBang river,Cao Bang province;S. langsonensissp. n. collected fromKy Cung river,Lang Son province in 2009-2010;and S. dakrongensissp. n collected fromDakrong river,Quang Tri province in 2012-2013.. This article provided description ofthese new specieswith theirscientific names,specific differencesin the genus and establishment ofidentificationkeysto species.

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.

Most vaccines usedin aquaculture are killed or inactivated pathogens. The goal of vaccination is the generation ofimmune response to administerantigen able to provide long -term protection against infection. To achive this objective, it requires the addition of an adjuvant. Among adjuvants, oil adjuvants are the most common used for vaccine in aquaculture. However, there were few studies describing mechanism reaction tooil adjuvant in fish. This study injected killed a polyvalent vaccines imulsified with Montanide TMISA 760 adjuvant against V.alginolyticus, V. parahaemolyticus, and V. harveyi causing Vibriosis in cobiaRachycentron canadum. The musculartissuesat the injection site was sampled at day 7, 14 và 21 post vaccination and fixed by buffer formaline 10% for histological observations. Histological sections were cut and stained by H&E to observe structure changes caused by oil adjuvant. The result showedthe the oil dropletsdeposited in the muscle and the muscular fibers were broken atthe injectionsite7 dayspost vaccination. At 14dyas post vaccination the sign of immune responsewith inflammatory cells surrounding the oil droplets forming granuloma.The inflamatorylesions and granuloma were observed more obvious at y 21days post vaccination. This study indicated that oil-based vaccine not only induced cellular immune response but also causedserious side-effectsat the injection site in cobia.

Histopathology provides a diagnostic method to detect the effects of irritants and pathogens in different fish organs and it can be used as an indicator for abnormal conditions in aquatic environments. The present study used histopathology to examine lesions on Grass carp (Ctenopharyngo donidella) gills associated with three common parasites. Fifty-eightGrass carp fry infectedwithmetacercaria of Centrocestus formosanus, Dactylogyrus sp. and Ichthyophthirius multifiliis r, were obtained fromfish farm nurseries. Symptoms, prevalenceand intensity were recordedandhistopathological examination was performed on sectioned gill tissuesstained with Haematoxylin-Eosin. Based on the results, the lesions in gill tissues caused by these three parasites exhibited similar characteristics as structural deformation and circulatory disturbances. However, each of them hadits own distinctive characteristics. The infection bymetacercaria of C. formosanuspresented severe lesions associated with moderate to severe hyperplasia of cartilage of the primary lamellae, epithelial hyperplasia, gill hemorrhage, congestion, and disorting andinflammation around the metacercarial cyst. Gills infected with Dactylogyrussp. mainly expressed epithelial hyperplasia, inflammation and lamellae damage due to the mechanical effects of hooks and toxic secretions. I.multifiliis causinghyperplasia and hemorrhage was noted withfurther study needed to clarify the histopathology at different stage of cyst formation.

This study was conducted to estimate breeding values (BV)of average daily weight gainBLUPs method ofstress negative Piétrain pigs raised atDong Hiep livestock farm, Hai Phong province and Animal farm of Vietnam National University of Agriculture. The dataof 373 individualswereused to estimate breeding values.In addition,BV estimates of 20 sires and average daily gain of504 stress negative Piétrain pigs (245 boars and 259 gilts) born from these 20 sires were used to estimate relationship between breeding values of sires and average daily weight gainof progenies.The results showed that there was apositive associationbetween breeding values of sires and average daily gain of progenies.Average daily gainof progeniesfrom the top 5% sires according to BV estimate was 551.20 g/day. These values decreased to 546.07, 536.94and 530.50 g/daywhenselection intensity decreased to 10%, 15% and 20%, respectively.Based on estimates ofbreeding value ​​by BLUPfor thestress negativePiétrain boarsthe the productivity performance of progenies was improved: the selected boar proportions5, 10, 15, 20% improved13.25; 12.20; 10.32; and 9%, respectively,of the average daily gainof progenies.

Dien Bien district is located in the northwestof moutainous area in Viet Namwhereprestigenatural,social and historical conditions existfor development of historical, culture and ecological tourism. Agricultural land use plays animportant role to support for development of tourismin the area in terms oflocal food supplywith specialtyproducts. In addition, appropriate land use enablesto create beautiful landscape and enhance traditional culture of Dien Bien area such as terraced fields, paddy fieldsin Muong Thanh valley, local fruitorchards, and gardens of vegetable, Bauhinia variegataandpeach flower and medical herbsto attact tourists. Four and 10 land use types of tourist potential were suggested for valley and slope land, respectively.

This study aimed to investigate the currentperformance in compensation, supports and resettlement in Van Don District. Data collection, survey, synthesis and comparative methodwere usedto evaluate the compensation, supports and resettlement of 2 key projects in Van Don District. Most of the land owners agreedthat the compensation,supports and resettlement have been implementedon time and compliedwith the laws. However, there were some limitations related toconpensation(compensation price lower than market value;payment by cash). Proposed solutions for these problems are Improving the capacity of institution in managing land, especially, in termsof land registry; compensation policy diversification;long-term aids and employment policies.

Coffee isone of the main crops cultivatedon basaltic soils in Gia Lai province. However, the development of coffee is facing with various problems, for example the age of coffee trees, soils degradation, etc.Analyses of physical and chemical properties of basaltic soils undercoffee replantation showed that the soils have high clay content in deeper layers. At the first (0-20cm) and second layer (21-50cm) of the soil the average bulk density value ​​was0.84 g/cm3and 0.89 g/cm3, respectively. The density characteristic was in the range of 2,19-2,69 at the first examined layer and keeps constant value into deeper horizons. The total porosity was66.53% and 64.55% in the first and second horizon of the soil, respectively.The pH valuewas around 4.3 to 5.54. The organic matter content and total nitrogen achieved moderate to highvalues. Total phosphorus and available phosphorus contents showedhigh levelin the first horizonbutlow levels (poor) in the second layer. The total potassium and available potassium were low. The concentrations of Ca++, Mg++exchange were relatively poor. At the pHKClvalues between 4.69- ≥ 4.72 in the both horizons, the mobile aluminum concentration was notfound in the examined soils layers.

The exact control of machanism position in agricutural machines is an important taskto improve the capacity and quality of the machines. According to resultsof the survey on imitative models of source circuitsin hydraulic system, the article provided soluttionsfor source circuit structure in position control used in agricuture to improve controlling propertysuitable forproduction conditions in Vietnam.

A higher order shear deformation theory (HSDT) was presented for free vibration analysis of simply supported (diaphragm), elastic functionally graded (FG), rectangular, plates. Functionally graded materials (FGMs), although heterogeneous,are idealized as continua with their mechanical properties changing smoothly with respect to the spatial coordinates.. Poisson’s ratio was assumed to beconstant,buttheirYoung’smodulianddensitiesvarycontinuouslyinthethicknessdirectionaccording to the volume fraction of constituents, which is mathematically modelled as power law function. The equations of motion were obtained using Hamilton’s principle employing HSDT. Navier’ssolution was used to solve the equations ofmotion. The effect of variation of material properties in terms of gradation index,the effects of aspect ratios, thickness-to-side ratio on the natural frequencies of FG plates werestudied in this article. The numerical results were compared with results available in the literature to validate theoretical model of the paper.

This paper studiedthe connection of wind farm using permanent magnet synchronous generators model to the main grid. The interests were the fault ride through capability and the ability to recover operation of wind turbines according to the wind grid code requirements. Wind turbine generators using permanent magnet synchronous potentially provide a definite reactive power depending on the instantaneous voltage level of connection point and they must return quickly to normal operation. Simulations were conducted by PSS/E.

Vietnam tourism is one of the key economic sectors that has contributed a considerable share (4.13%) to GDP of the country in 2012. With many beautiful landscapes, diverse cultures, long history, etc. Vietnam has been rated as a fully potential destination for foreign visitors. However, high inflation in the host country resulted in expensive tourism expenses may affect the volatility of foreign visitors to Vietnam. The paper examined the effects of the 1, 2, 3, 4, 5 and 6 month lagged consumer price indices (CPI) as exogenous (X) variableson the volatility of foreign visitors to Vietnam, using the GARCH(1,1)-X models. The results showed that the volatility of foreign visitors to Vietnam is characterized by a heteroscedastic process and the volatility is positively influenced by the lagged CPI. The findings are important implications for policy makers, tourism enterprises and investors in Vietnam tourism industry.

Usingdatagatheredfrom surveying 132 taxpayers and applying exploratory factor analysis method and regression model, the presentarticle discusses the evaluation of tax-payers toward service quality of Na Hang District’sTax Bureau ofTuyen Quang Province. The study results showedthatservice quality,in general, has met the demand of tax-payerswith approximately 79,3%tax-payers satisfied with sevice quality. The research also identifiedseven factors affecting the satisfactory degrees of tax-payers. Those are: trustability, infrastructure, sympathy, equity and democracy, service capability, transparence/openess and accountability and responsiveness. The article also proposedmeasures to improve and enhance service quality of the tax bureau,thereby to enhance the satisfactionof tax-payers.

Goverment’s supportive policy is important leverage to promote the enterprise development, especially in the economy slow-down period. However, in the course of policy implementation severalproblemsarise. With theinformation collected by interview methods using a set of questionaireforimplementingagenciesandthe beneficiary enterprises, this article showedthat gorverment’s supportive policy in Nghe An province has brought positive impacts on enterprise development,contributing to increasing capital, reduction ofproduction costs, and relievingbusiness problems in therecessionperiod; thereby promotingthe development of enterprises in the province.In addition, the article pointed out shortcomings of policy mechanisms, such ascomplicated procedures for receiving support, inadequatelevels of support, low enterprises’ accessibilityto the support… From these evaluations, the authorsmade a number of proposals to improve the effectiveness of policy support in the future.