Published: 2020-04-29

Efficacy of propylene glycol on prevention and treatment of ketosis for dairy cows in lactation stage

Hai T. Nguyen, & Toan T. Diep
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.4.02.2020
Abstract | PDF (260.1K)

Abstract

The objective of this study was to evaluate the efficacy of propy-lene glycol (PG) on prevention and treatment of ketosis in dairy cows from 09/2018 to 03/2019. The study consisted of 2 exper-iments using a total of 126 multiparous dairy cows in a HF crossbred herd. Cows in both experiments were randomly as-signed to treatments in a randomized complete block design. In Exp. 1, 96 cows without ketosis disease (BHB < 1.4 mmol/L) were assigned to 2 groups (48 cows/group), including (1) un-treated control group (no PG) and (2) treatment group (oral PG for 3 consecutive days after parturition). In Exp. 2, 30 ke-totic cows (BHBA < 1.4 mmol/L) were divided into 3 groups (10 cows/group), including (1) cows provided with glucose + vitamin B12 + dexamethasone (TT1), (2) cows treated with PG for 3 days (TT2), and (3) combination of TT1 and TT2 (TT3). The results of the Exp. 1 showed that the proportion of ketotic cows was lower (P < 0.01) in the PG-treated group (18.75%) than in the control group (47.92%). The PG treatment also reduced (P 0.05).

Production of fish seasoning powder from snakehead meat (Channa striata) by applying Alcalase and Flavourzyme enzyme mixture

Thu T. M. Truong, & Thuy T. M. Le
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.6.02.2020
Abstract | PDF (260.1K)

Abstract

Fish hydrolysate was produced from snakehead meat by applying an enzyme mixture consisting of Alcalase and Flavourzyme with a ratio of 1:3; hydrolysis temperature 55oC; pH 6.5 – 6.9. The results showed that the ratio of enzyme mixture to fish meat of 0,2% and hydrolysis time of 26 h were the optimal hydrolysis conditions. Fish hydrolysate had highest peptide content (26,4 g/L) and nitrogen amino acid content (10,6 g/L), and lowest nitrogen ammonia content (0,257 g/L). Sensory score, protein content, recovery yield and moisture content of fish seasoning powder were 18,9; 17,1%; 42,5% and 4,88%, respectively by mixing radish solution and fish hydrolysate at the ratio of radish solution to fish hydrolysate of 25%:40% and drying at 60oC for 72 h. The product still remained good sensory quality. The moisture content and total aerobic bacteria of product were at acceptable level after 4 weeks stored at ambient temperature.

Replacement of rotifer with Artemianauplii in clownfish larvae rearing (Amphiprion percula Lacepede, 1802)

Trang T. L. Tran, & Dung V. Tran
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.5.02.2020
Abstract | PDF (260.1K)

Abstract

This study was conducted to minimize the period of using rotifer in rearing percula clownfish larvae from newly hatched to 30 days. Artemia nauplii was used to replace rotifer when the larvae reached 5, 7, 9, 11 and 13 days after hatching (DAH). The results showed that larvae fed with Artemia nauplii starting from 7 DAH achieved the highest specific growth rate in standard length (4,02%/day). The later the starting point of weaning was, the lower the larval specific growth rate was. The lowest specific growth rate was at 13 DAH (3.21%/day;P    0.05). Similarly, the starting points of weaning times had no significant effects on larval survival rate, ranging from 39,6 - 48,2% (P > 0.05). The results of this study helped reduce the period of using rotifer in rearing the clownfish larvae which contributes to the improvement of larval performance in artificialre production of this species.

Isolation of agarase-producing bacteria from seawater and examination of the enzyme activity

Lien T. H. Nguyen, Phong V. Nguyen, & Thanh T. L. Bien
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.7.02.2020
Abstract | PDF (260.1K)

Abstract

This study aimed to isolate agarase-producing bacteria from seawater, and then determine activity of the agarase. Eight coastal surface seawater samples were collected from Ba Ria -Vung Tau province. Twenty-one bacterial strains that are ca-pable of liquefying agar were isolated. These isolates produce ddisintegration zones around their colonies on agar plates with diameters ranging from 4.0 to 7.0 cm after an incubation period of 2 days at room temperature. Five bacterial strains (M1, M5, M7, M62B, and M71) that produced large halos on plates were identified belonging to Vibrio genus with identity  > 96%. The crude enzyme activities of these strains ranged from 0.15 to 0.22 U/mL in reaction with agarose as substrate. Among isolated strains, the strain M71 showed the highest agarase activity, and was used to examine the degradation of seaweed. The hydrolysis of dried Gracilaria seaweed by the crude enzyme of M71 at concentration of 5% (v/v) released 915 μM/mL reducing sugar after a 24-h incubation period at 40oC.

Processing of fermented fruit juice from acerola (Malpighia glabraL.)

Mai T. N. Tran
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.12.02.2020
Abstract | PDF (260.1K)

Abstract

Fruit cider has high nutrition and often preserved cold after processing.The aroma and flavour characteristics of the original material enhancethe sensory of the cider. This study was carried on the acerolajuice which has the dry matter concentration of 18oBx, pH 4.0. Thefermentation was induced with the yeast content of 0.20% for 3 daysat room temperature. As a result, the obtained product had the drymatter concentration, the alcohol content, the vitamin C content andpH of 7.2±0.8oBx, 1.4% v/v, 581.2 mg% and 3.1, respectively.

Alpha-glucosidase inhibitory activity of some brown seaweeds collected in Nha Trang bay, Khanh Hoa province

Han T. Nguyen, Duong T. H. Ngo, & Yen T. P. Nguyen
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.11.02.2020
Abstract | PDF (260.1K)

Abstract

Diabetes has become a global problem in recent years. Inhibition of α-glucosidase is one of the effective approaches to control the post-prandial blood gluccose and thereby mananging diabetes. This study evaluated inhibitory activity of seven brown seaweed extracts (Colpomenia sinuosa, Padina australis, Sargassum aquifolium, Sargassum mcclurei, Sargassum duplicatum, Sargassum polycystum và Sargassum swartzi) against α-glucosidase. The results indicated that all seaweed extracts inhibited enzyme activity with the IC50 values ranging from 154.27 to 426.27μg/mL. The seaweed Sargassum mcclurei showed the highest α-glucosidase inhibitory activity. The effects of extraction conditions and extraction solvent fractions on α-glucosidase inhibitory activity of Sargassum mcclurei were investigated. The suitable extraction conditions were found to be the solid to liquid ratio (g/mL) of 1/40, the extraction time of 60 min and the extraction temperature of 60oC. The ethyl acetate extracted fraction showed the highest α-glucosidase inhibitory activity compared with other fractions.

Evaluating the decision to participate in a fair trade model of coffee-producing households in Xuan Truong commune, Da Lat city, Lam Dong province

Nam H. Tran, & Han T. N. Tran
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.1.02.2020
Abstract | PDF (260.1K)

Abstract

Fair trade in coffee production offers an opportunity to improve farmers’ position in the market. The study used a logit model with the maximum likelihood estimation method to evaluate the famers’ decision to participate in a fair trade coffee production model. Data were collected by directly interviewing 220 farmers in Xuan Truong commune, Da Lat city, Lam Dong province. This commune has applied the fair trade model in coffee production with the brand of Cau Dat coffee. The results of this study showed that the probability of households deciding to participate in the fair trade coffee model was 14.43%. In addition, factors affecting the decision to participate in the fair trade coffee model were householders, education level, area of agricultural land, profitability, awareness of fair trade, desired price of coffee, and agricultural extension. In particular, the farmer’s awareness of fair trade and the desired price of coffee had positive impacts on the farmers’ participation in a fair trade coffee model.

Consumer’s behavior towards organic food: A case study in Ho Chi Minh City

Hoa T. T. Ha, Luan D. Tran, & Linh T. N. Nguyen
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.2.02.2020
Abstract | PDF (260.1K)

Abstract

This study aimed to examine factors influencing consumers’ behavior towards organic food. Structural equation modelling (SEM) was used to test the relationships between the factors through data collected from 450 consumers in Ho Chi Minh City. Research results showed that consumption intention had the greatest direct impact on consumer behavior. Subjective norms had the strongest influence on consumption intention, followed by the attitude towards organic food. In addition, the price of organic food was a barrier to consumption intention towards this food. At the same time, the results of the multi-group analysis showed that the relationships in the models were not significantly different between male and female, but significantly different among income groups.

Survey and analysis of flowers and ornamental plants at some nurseries in Ho Chi Minh City according to criteria for garden design

Tien T. M. Duong, & Thuy T. Vuong
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.8.02.2020
Abstract | PDF (260.1K)

Abstract

This research was carried out from October 2017 to October 2018 at some ornamental plant stores and nurseries in district 7, Go Vap district, district 10, Tan Binh district and Binh Chanh dis-trict. These are important ornamental plant trading and producing areas in Ho Chi Minh City. This study aimed to identify and anal-yse the potentials of using ornamental flowers, plants and trees for garden design. The investigation was conducted through question-naire surveying, morphological comparison, species identification. The collected data was then statistically analysed. We divided these districts by zones and routes for the invesgation. There were 542 identified ornamental plant species in Ho Chi Minh City. Ac-cording to the analysis of 7 important groups of ornamental plants such as tree trunks, shape of the tree, leaves, and flower groups, the bonsai pots for interior display, with large leaves, dark green to light green colors, large flowers, height from 0.1 to 1 m and no fra-grance is common. Briefly, the obtained results would contribute to the design and construction of gardens in Ho Chi Minh City.

Assessment of climate change adaptation capacity of agriculture in Ho Chi Minh City

Linh T. Vu, Loi K. Nguyen, Ngoc T. A. Pham, & Dung M. Ho
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.10.02.2020
Abstract | PDF (260.1K)

Abstract

This research used sociological survey method combined with Likert scale and the factor analysis method to assess adaptability to climate change from 4 factors including awareness of climate change, experience in responding to climate change, government support and access to resources. Based on the results of social survey of 10 districts related to agricultural activities in Ho Chi Minh City, the research calculated the score for 4 criteria and zoning for climate change adaptation value for each district. The results showed that high and average –resilient districts were Cu Chi, 9 and 12. Cu Chi was rated to have the highest adaptability, with an overall adaptability value of 0.86. Indeed, Cu Chi district was noted for having support from the government and access to the highest level of support among the 10 districts. Meanwhile, Binh Chanh, Go Vap and Thu Duc districts were located in a low adaptability area.

Correlation between nematode and soil properties on some pepper-cultivated areas in Gia Lai province

Sinh N. Nguyen, Tuan Q. Le, & Han T. N. Le
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.9.02.2020
Abstract | PDF (260.1K)

Abstract

The research aimed to understand the soil structure for pepper agriculture, the relationship between nematodes distribution and some soil quality parameters. Secondary data collection, field survey, and soil sampling and analysis were conducted in field and in laboratory. The results showed that the soil had pH values ranging from acid to neutral, average N and P levels, and high organic matter content. The isolation of nematodes showed that there were 26 genera of nematodes belonging to 17 families and 7 orders in soil. The lower the soil organic matter content and pH value were, the higher the density of nematodes was, indicating the possibility of survival and development of nematodes in extreme soil environment. This is one of significant factors that may impact the pepper produc-tivity. Therefore, increasing nutrient contents of soil would prevent nematode activities and at the same time enhance the resistance of pepper to nematodes.

Analysis of genetic diversity of 100 cashew (Anacardium occidentale L.) cultivars screened in Binh Phuoc based on nut yield and ISSR markers

Toan D. Pham, Tri M. Bui, Duc M. Tran, & Thu T. Nguyen
Electronic version: 29 Apr 2020 | DOI: 10.52997/jad.3.02.2020
Abstract | PDF (260.1K)

Abstract

Cashew (Anacardium occidentale L.) is an important tropical tree, belonging to Anacardiaceae family and has high economicvalue growing in Vietnam. The objective of this study was to assess genetic diversity of cashew distributed in Binh Phuoc province for breeding development and conservation. A total of 100 cashew samples of over 10 years age distributed in BinhPhuoc province were divided into eight main groups based on nut yield. In contrast, the cluster analysis was divided 100 cashew samples into 12 groups based on 11 ISSR markers. The genetic diversity of 100 cashew samples ranged from 0.04 to 0.26, with a mean of 0.19. The results showed that cashew samples were high levels of polymorphism based on nut yield, as well as the ISSR markers. The results of this research would be one of the important information in the genetic evaluation of cashew trees and useful information for cashew breeding development in future.