Vol. 17 No. 2 (2019)

This study was carried out to evaluate agronomical characteristics, yield and submergence tolerance of inbredrice lines thathave been selected fromcross combinations betwwen purerice line and cultivars with lines carrying submergence tolerance gene Sub1. The field experiments were conducted at Gia Loc district, Hai Duong province. Out of 24 inbred lines, 6 promising ones selected possessed good characteristics,such as short growth duration, medium plantheight, short flagleaves, slight pestinfestation, high yield as well as with the high milled rice tohead riceratio, and low to moderate amylose content. Basedon PCR amplificationusing twoSSR primers SC3 and ART5, the resultsshowed that all lines carried the submergence gene Sub1. The most promising line,U1080,selected from the cross between TL6/and Swarna-Sub1 haddesirable growth duration, slight pest infestation, high yield and good eating quality. Thus,for the improvement of submergence tolerance, therice cultivars should be crossedwith the materialscarrying submergence tolerancegeneandindividuals selectionbe practicedin the segregatingpopulationfor furtherevaluation ofagronomical characteristics in both normal and flooding conditions.

The objective of the present study was to determine the safety and efficacy of vaccine Han-Streptila incommercialtilapia by injection (in Hau Giang, Tien Giang and Dong Thap provinces) and by oral route (in An Giang, Vinh Long and Dong Thap provinces). The control, immune and safe groupswere set up in each province. The safety of the vaccine was determined by observing the abnormalities of experimental fish; the efficacy of the vaccine was determined by comparing the final cumulative mortality between thevaccinated groupandthe control group during the trial or after challenge test. This also was evaluated throughrelative percentage survival(RPS).The results showed that the vaccine hadno effect on mortality and growth of fish. Thevaccineefficacy through injection with tilapia of 10g/p achieved 66.9% and oral route for fish 2.5g/p achieved 63.9% protection after 24 weeks. Therefore,HAN-STREPTILA vaccine tested in the South of Vietnam wassafe and highly effective.

To determine the infection of fishborne zoonotic trematodes (FZT), metacercariae stage, in juveniles and grow-out Sutchi catfish in Tiengiang province,aresearch was conducded from April 2017 to April 2018 with a total of 272 grow-out fish (at 48 ponds) and 3320 fingerling fish (at 64 ponds). Fishsampleswere tested with the parasite method and metacercariae genus were identified by morphology method. It was found that fish were infected with Haplorchis pumilio metacercariae and the prevalences in the fish were higher during the rainy season compared to the dry season (the prevalence of fingerling pond was from 12.5 to 37.5% andgrow-out fish was from 12.1 to 30.0%for the rainy season; the respective figure were from 0.0 to 13.3% and from 0.0 to 25.0%for the dry season). Drying the pond bottom (<2 days), home made food, a snail's presence in ponds and dog/catpresence ) in the farming area were found to be the risk factors of FZT in the fish (P <0.05). Therefore, technical controls should be done to prevent and decrease the FZT prevalence in figerling and grow - out Pangasianodon catfish to contribute to the food safety and human health.

Canine Parvovirus type 2 (CPV-2) has caused a highly contagious and fatal disease characterized by vomiting and hemorrhagic gastroenteritis in dogs of all age.In this study, four diarrheal stool samples collected from Parvovirus-infected dogs were used for VP2 gene sequencing. The results of VP2 gene sequencing and analysis of present CPV strains showed high nucleotide (nt) and amino acid (aa) identities when compared with those of other reference worldwide strains, sharing 98.4 - 100% nt and 97.7 - 100% aa. The results of the phylogenetic tree showed that the Parvovirus type 2 in this study was genetically classified into two distinct groups of Feline Panleukopenia Virus (FPV) and CPV. Three strains VNUA-CP31, VNUA-CP32 and VNUA-CP35 belonged to the branch of FPV and close to the FPV in China. Parvovirus type 2 VNUA-CP17 belongsto the branch of CPV and is close to Parvovirus vaccines of the Pfizer and South Korea.

A study was carried out to evaluate the effect replacement of cornwith broken rice in the diet on the performance of growing-finishing pigs.Two hundred forty cross-bred D (LY) growing- finishing pigs (68 days old)were alloted intoa completely randomized design of fourtreatments with 3 replicates of 20 pigs each.Treatments consisted of graded levels of broken rice (0, 25, 50 and 75%) to orreplace cornin the diet. Results showedthatwhen using broken rice as substitutefor75% corn in the diet, the body weight, average weight gain (kg/head/day), the dressing percentage, carcasspercetage, eye muscle areaand leanmeat percetage,andmeat shear forcewere higher in comparison with25% and 50% of broken rice replacements and100% corn. The use of broken rice as substitue for corndid not affect feed intakeand feed conversion ratio (kg feed/kg body weight gain), carcass length, backfatthickness, pH45 ', pH24h, meatcolor, rate of water lossduring storageand feed cost per1 kg weight gain. It is therefore suggested thatbroken rice can replace up to75% corn in the diet of growing - finishing pigs.

The objective of this study was to assess genetic diversity and genetic differentiationbetween Lạc Sơn chicken and other native chicken breeds using 20 microsatellite markers. The resultsindicated that microsatellite markers studied werepolymophic with an average of 6.73 alleles/locus. The genetic diversity of Lạc Sơn chicken was on theaverage level with the expected heterozygosity of 0.60 and the number of alleles/locus was 6.05.The inbreeding coefficient of Lac Son chicken was very low. The lowestgenetic distance was found between Lạc Sơn chicken and Đông Tảo chicken but the highestgenetic distance was found between Lạc Sơn chicken and Tai đỏ chicken.Sub-structuring of the Vietnamese chicken breeds was related to their geographical distributiondistance. Three chicken breeds, viz. Ri, Đong TaoandMia,in the Red River Delta were in the same group, while Lac Son chicken in the northern central region was seperatedand different from Tai Đỏ chicken (Red Jungle Fowl) breed.

In agricultural production, irrigation water is at the forefront, especially in the context of climate change. The objective of this study wasto predictthe irrigation waterrequirementsfor the major land use types in the Srepok basin and to propose agricultural land-use planning to support decision makers in integrated river basin management towards sustainable development. The modeling approach under thesupport ofCROPWAT 8.0and assessment of natural land adaptation process were applied in the study. Irrigation demand for coffee, pepper, cashew, rubber, tea, rice, maize and cassava were calculated in 2015with highest value of 7.746 m3.ha-1.crop-1forwinter-spring rice. Theirrigation water wasforecast for the future (2045) with decreasing trend in three scenarios (11.7% for low scenario, 18.59% for average scenario and 4.25% in the high scenario) compared to the presentperiod. Furthermore, three maps for agricultural land-use thatdefine suitable areasand spatial allocation of land use plans, were proposed with climatechange scenarios as a response solution.

The present study aimed to evaluate phosphorus (P) buffering capacity and risk of P leaching to the environmentin the long-term reduced P application in the triple rice cropping paddy fields in Bac Lieu provincein the Mekong Delta of Vietnam. The soil samples were collected in the harvest stage of Winter-Spring (WS) 2013-2014 crop on the fields thatwere applied withreducedP fertilizerforsevenconsecutive crops (from WS 2011-2012 to WS 2013-2014). The P solutionsfrom 0to 60mg P/L concentration were added to the soil samples within 24 hoursto determine the soil absorption of P. The results showed that the P absorptiondecreased when the P concentration to soil samples increased in allreducedP fertilizer treatments. The P bufferingcapacityvaried in the rangeof123-132 mg P/kg and it reduced when applied 60 kg P2O5/ha compared withoutP application, with20 kg P2O5/ha or with 40 kg P2O5/ha. The degree of phosphorus saturation (DPS) ranged from 9.15 to15.6% and continuousapplication ofPatthe rate of 60 kg P2O5/hamight result in P leaching risk. It is recommended thatDPS in the other paddy soils be studied to assess the risk ofPleachingto environment,consequently, to enhance the P efficiency management in rice production in the Mekong Delta of Vietnam.

The objective of this study was to design and develop a wall painting equipment to gradually replace human laborand increase labor productivity. The study was conducted to design and fabricate wall painting machine with a flow of 54 liters per hour. Based on the theoretical calculation, application of graphic design software, experimentation, and the principle of working, the parts of wall painting machine were designed and fabricated. Specially, based on the theories of general hydraulics and machine design, the automatic paint pumpingsystem, a type of peristaltic pump, was designed to be suitable for painting solution and painting system. The project has successfully fabricated the wall painting machine with the capacity of 300 m2 per hour, 3-4 times higher than that of the manual painting equipment with cheap manufacturing cost. The quality of painting surface did not depend on the skill of painters In addition, the system is quite compact, easy to move at construction place.