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Artemia parthenogenetica is an emerging species used in marine hatcheries in Vietnam. Disinfection during their cyst incubation is important, however, disinfectants might have side-effects. This study examined the effects of polyvinylpyrrolidone coated nanosilver particles (AgNPs) on A. parthenogenetica cyst hatching and nauplii development. Cysts were exposed to low (0.1, 0.4, 0.7 mg/L) and high (1, 4, and 7 mg/L) levels of AgNPs for 48h. The total Vibrio in incubated water and nauplii significantly decreased when AgNPs were applied, however, the hatching success significantly reduced when the AgNPs level exceeded 1 mg/L. Nauplii instar I and instar II were exposed to 10; 50; 100; 200; 500; 600; 700; 750; 800; 900 and 1000 mg/L to determine their LD50. The LD50-36h and LD50-48h of AgNP on Instar I were 136.5 and 53.21 mg/L while those on Instar II were 22.15 and 12.1 mg/L.    

The objective of this study was to determine the effects of 2,4-Dichlorophenoxyacetic acid (2,4-D) combined with 6-Benzylaminopurine (BAP) and sucrose on the shoot and root regeneration of Paph. micranthum var. North Vietnam. Young fresh leaves were cut into small explants and then cultured on media containing 2,4-D (0.5, 1.0, or 2.0 ppm). Within each of the 2,4-D concentration, BAP was added at three different concentrations (0.5, 1.0, or 2.0 ppm) for callus induction after 4 weeks. Shoot tips (2-3 mm in length) from the leaf-derived calluses were then transferred vertically on half-strength MS medium (2,4-D combined with BAP (0.5, 1.0, or 2.0 ppm) for shooting, and rootless shoots with 2 leaves were transferred to the same MS medium for rooting after 4 months of culture. Rootless shoots with 2 leaves were also transferred vertically on half-strength MS medium with different sucrose concentrations (0, 10, 20, 30, or 40 g L-1) to optimize the growth and development of the plantlets. The results indicated that the optimum degree of shoot and root regeneration occurred on half-strength MS medium containing 2.0 ppm 2,4-D combined with 2.0 ppm BAP. Approximately 86.6% of the cultures responded with 3.3 shoots and 3.0 leaves/explant. In addition, under the optimal concentrations, the number and length of roots per explant after 4 months of culture were 2.1 roots per explant and an average root length of 1.1 cm. MS medium supplemented with 30 g L-1 sucrose had the highest number of leaves and roots, and also the longest average length of roots, which gave 3.8 leaves, 3.3 roots/explant, and a root length of 1.8 cm after 4 months.

Mineral nutrients are essential to plant growth and development. The present study aimed to evaluate the effects of mineral fertilizer doses and N:P:K ratio on growth, yield, and raw material quality of the tea variety PH10 to improve the production of high-quality tea products. The field experiment was conducted from 2015 to 2017. A two-factor experiment was designed by pplit-plot design with three replications. The mainplot treatments were three fertilizer doses of N  for one metric ton of fresh shoot products (30, 40, and 50 kg N ha-1). The subplot treatments were two NPK ratios (3:1:1 and 3:1:2). Plant height, leaf canopy, plant diameter, shoot yield parameters, shoot components, biochemical compounds, and sensory quality for Oolong and Sencha tea products were evaluated. The results showed that increasing fertilizer doses improved remarkably growth, yield, and made tea quality of PH10 variety up to 40 kg N ton-1. Different fertilizer ratios resulted in variations in plant growth, the content of carbohydrate, sensory quality for taste and flavor as well as total sensory quality with higher values at NPK ratio of 3:1:2. Applying mineral fertilizer with an NPK ratio of 3:1:2 and  40 kg N per ton of fresh shoot products was recommended to bring about the most benefits of tea yield and quality as well as economic profit.  

The objectives of this study were to evaluate the effects of nitrogen forms on root system development (expressed as total root length, nodal root number, nodal root length, and lateral root length), water use, photosynthetic rate, and dry matter production under water deficit (WD) at 20% w/w and continuously waterlogged (CWL) conditions. Rice plants cv. Nipponbare were grown in plastic pots in a vinyl house. Six N forms were applied at the same rate of 360 mg N per pot, and were prepared as follows: N-NH4+ alone (A); N-NH4+ with nitrification inhibitor (A+DCD); N-NO3- alone (N); N-NO3- with nitrification inhibitor (N+DCD); combined N-NH4+ and N-NO3- (AN); and combined N-NH4+ and N-NO3- with nitrification inhibitor (AN+DCD). The nitrification inhibitor, dicyandiamide (DCD) (C2H4N4), was applied at the rate of 100 mg pot-1. The results of the experiment showed that under both WD and CWL conditions, significant increases were seen in the root system development as expressed through total root length, nodal root number, nodal root length, and lateral root length in the N-NO3- treatments with and without DCD compared to the application of N-NH4+ treatments with and without DCD. This led to an increase in water use, and eventually a significant increase in dry matter production. Similarly, the A treatments with and without DCD also significantly increased root system development as compared with the AN and AN+DCD treatments. Furthermore, under both CWL and WD conditions, the positive and notably significant correlations between the total root length and water use, as well as between the total root length and shoot dry weight, were found only in the A and A+DCD treatments. These results indicate that rice prefers sole ammonium over the mixed ammonium-nitrate treatment, and sole nitrate applications under both WD and CWL conditions.

Context. Tannin found in many plants has traditionally been used as medicine for diarrhea treatment in pigs, but few in vivo studies have been conducted in piglets. Aims. This study aimed to evaluate the effects of tannin supplementation on post-weaning diarrhea and the growth performance of weaned piglets. Methods. Eighty one Duroc x (Landrace x Yorkshire) piglets were randomly allocated to age and sex-balanced groups: 27 for a control group with basal feed (CON) and 54 for a treatment group with a supplementation of a 0.25 g tannin blend for every 1.0 kg of the basal feed (TAN). At weaning, each piglet was individually identified by ear tag and had their diarrhea status recorded for 30 days. The body weights were recorded at weaning (IBW) and at the finishing period (FBW) to calculate the average daily gain (ADG). Diarrhea was identified by scoring fecal consistency twice per day. Key results. The obtained odds-ratio for the treatment and for IBW were 3.014 and 0.841, respectively, showing positive effects of the TAN and increased IBW on the diarrhea rate. Increasing the IBW by one kilogram led to a decrease in the diarrhea rate by 0.841 times. The FBW and ADG in TAN were higher (P = 0.0089 and P = 0.0044, respectively) than those in CON. Conclusions. Tannin supplementation at the rate of 0.25 g per 1.0 kg of feed helps prevent post-weaning diarrhea and improve ADG in weaned piglets. Increasing body weight at weaning also reduces the diarrhea rate.

This study evaluated the effects of binder type (molasses and cassava flour) and inclusion level (5% and 10%) on the physical and nutritional properties of pellet feeds formulated with fruit by-products (pineapple and passion fruit peel). A 2×2 factorial design was used to assess the impact on pellet durability, length, density, chemical composition, and amino acid profile. The result found that Results indicated that binder type and dosage significantly influenced key physical parameters and nutrient composition (P < 0.05).  The significant interactions between binder type and inclusion level were observed for pellet durability, length, density, NDF, sugar, starch, saponin, and several amino acids including aspartic, glutamic, threonine, alanine, agrinine, lysine, leucine and proline acid (P < 0.05). Among treatments, 10% molasses as a binder is optimal for enhancing both the physical integrity and nutritional quality of pellet feeds containing fruit by-products, offering a promising and sustainable feeding strategy for ruminant production.

This study investigated the potential of replacing soybean meal with lupin (Lupinus angustifolius) at varying inclusion levels in the diets of growing–finishing pigs from 12 to 22 weeks of age. A total of 120 crossbred pigs (Duroc × [Yorkshire × Landrace]) were randomly assigned to four dietary treatments: a control diet without lupin (LP0), and diets containing 5% (LP5), 9% (LP9), or 12% (LP12) lupin. Growth performance parameters were recorded over a 70-day feeding period. Pigs fed the LP12 diet exhibited significantly lower body weight and average daily gain (p<0.05) compared to those fed LP0, LP5, and LP9 diets. Feed intake did not differ significantly among treatments (p>0.05), whereas feed conversion ratio was significantly higher in the LP9 and LP12 groups than in LP0 and LP5 (p<0.05). Economic analysis indicated that the LP5 diet provided the greatest economic benefit, reducing feed cost per kilogram of gain without impairing performance. These findings suggest that dietary inclusion of lupin up to 9% does not compromise growth performance, with 5% being the most economically advantageous level for fattening pigs.

African Swine Fever Virus infections have significantly impacted swine production in many parts of the world.  Rodents are considered vectors of several swine disease agents, but their role in ASFV transmission has not been determined.  This work sought to determine whether rats could be experimentally infected with ASFV.  In a pilot project prior to the experimental trial, 27 rats, mice, and shrews were trapped from 3 farms (range 7-10 per farm) with current ASFV outbreaks.  These animals were euthanized, sampled, and tested for ASFV with polymerase chain reaction.  None of the samples (n=81) were PCR-positive for ASFV.  The experimental trial utilized 45 commercially obtained rats (Rattus norvegicus domestica): 9 orally inoculated with ASFV, 9 intraperitoneally inoculated, 18 non-inoculated contacts, and 9 negative controls.  On each of days 7, 14, and 21 post-inoculation, 3 orally inoculated rats, 3 intraperitoneally inoculated rats, 6 non-inoculated contact rats, and 3 negative control rats were euthanized, sampled, and tested for ASFV with PCR.    Clinical signs did not develop in any of the rats. Body temperatures climbed during week 2, but there was no difference between inoculated and non-inoculated groups.  None of the samples (blood, spleen, liver, lung, and ileum) were ASFV-positive on PCR.  Serum tested by ELISA for ASFV antibodies was negative.  Despite direct ASFV challenge, inoculated rats did not develop clinical disease or transmit ASFV to contacts, indicating that rats were unable to serve as biological vectors for ASF. 

The effect of conventional cage and cage-free systems on welfare quality of laying hens has been assessed recently, but with contrary results. This study aims to identify welfare issues of laying hens when keeping in battery cage and deep litter system at a commercial farm. In cage system, white hybrid hens were kept in three cage lines, three hens per cage and two tiers per line. In the deep litter system, hens were equally allocated to three compartments of a barn. Hen welfare was assessed at 5% of laying, peak period and end of laying with main health and social behaviour parameters according to Welfare Quality ® (2009). A total of 450 hens were randomly chosen from different locations of the barn and cage for scoring by one assessor. The logistic analysis was applied using a proportional odds model to compare the prevalence of each welfare measure among two housing systems at a significant level of 5% by R software. Hens in the conventional cage had a worse plumage condition and keel bone deformation than those in the deep litter system, especially at the end of laying (P<0.05). In the deep litter system, hens showed a higher prevalence of foot pad dermatitis (46.0% hens scored 1 in deep litter system compared with 11.33% in cage) and a higher avoidance distance test at different ages (P<0.05) than those in battery cage. The deep litter system shows a better benefit for hen welfare than the battery cage except foot pad dermatitis.

Probiotics and prebiotics are increasingly encouraged in aquaculture to reduce antibiotic use. The present study aimed to investigate the effects of dietary supplementation of peptidoglycan or Lactobacillus plantarum or its combination on the growth performance, disease resistance, and immune status of striped catfish juvenile. Fish were fed on the commercial feed supplemented with various concentrations of peptidoglycan and Lactobacillus plantarum at 0, 5, 5, 2.5 + 2.5, and 5.0 + 5.0 per kg of feed, named to PP0.0, PG5.0, LP5.0, PP2.5, and PP5.0 treatments. Fish were then fed at a ration of 3% of fish body weight for 6 weeks. After feeding trial, fish were infected with Aeromonas veronii at 50% lethal dose (LD50, 107 CFU/mL). Blood samples were collected after 2, 4, and 6 weeks of experiment (T2, T4, and T6) and at second day after bacterial infection for hematological parameters and immune assays. The results demonstrated that supplementation with PP2.5 significantly improved growth performance and feed utilization in fish, while the LP5.0-based diet reduced mortality in A.veronii-challenged fish, indicating enhanced disease resistance. The modifications in hematology and immune status were affected by pro-, pre-, and synbiotics tested in this study. In conclusion, dietary supplementation with peptidoglycan and L.plantarum enhances growth, immunity, and disease resistance in striped catfish, supporting sustainable aquaculture practices for improved fish health and production efficiency. 

In this study, six mathematical models including von Bertalanffy, Janoschek, Gompertz, Logistic, Lopez, Richards were employed to analyzed the growth curve and predict the optimum slaughter age of Na Tau ducks. Body weight data were collected weekly from birth to ten weeks of age. The parameters used to evaluate the growth functions were the coefficient of determination (R2), the AIC (Akaike's information criterion), BIC (Bayesian information criterion) and the standard error of the regression function (SER), as analyzed using R software. Among the models tested, the Janoschek model provided the best fit for both male and female ducks. The asymptoic body weight of male ducks ranged from 2213.16 g (Logistic model) to 2726.58 g (Lopez model), whereas for female ducks, it was estimated between 1968.89 g (Logistic model) to 2401.25 g (Lopez model). The age at the inflection point was estimated from 3.36 to 4.59 weeks for males, and from 3.09 to 4.33 weeks for females. The average weekly gain (AWG) estimated by the best-fit model were recorded at 6.79 and 6.32 weeks for males and females, respectively. Based on these findings, the optimal slaughter age was determined to be 6.79 weeks for male Na Tau ducks (with a body weight of 1736.07 g) and 6.32 weeks for females (with a body weight of 1523.58 g).

This study aimed to find the best model to describe the growth of Tien Yen female chickens and predict the live weight, weight gain, and suitable slaughter age. The body weights of 500 female chickens were measured every week from birth to 24 weeks of age. The chicken of control group was fed local resources such as agricultural products (yellow corn, and rice bran) and commercial feed. The chicken of treatment group was fed the treatment diet. The data for growth performance was analyzed in R using six mathematical functions (von Bertalanffy, Janoschek, Gompertz, Logistic, Lopez, and Richards). The best models to describe the growth of Tien Yen females were Gompertz and Richards, respectively. This α value for Tien Yen female raised by the control group was estimated to be from 1,674.02 g (Logistic) to 1,762.14 g (von Bertalanffy) and this value for Tien Yen female raised by the treatment group was from 1,833.47 g (Logistic) to 1,970.95 g (von Bertalanffy). The estimated age for the control group at the inflection point was between 6.20 and 10.42 weeks, whereas, this figure for the treatment group was from 6.74 to 9.78 weeks. The maximum absolute growth rate (monthly gains) occurred at 10 and 11 weeks of age for the control and treatment groups, respectively. This suggests the suitable slaughter ages are from 14.75 weeks (1,478.10 g) to 15.16 weeks (1,546.43 g) for female Tien Yen chickens.

Spotted sea bass (Lateolabrax maculatus, McClelland, 1844) is a species belonging to the genus Lateolabrax (Lateolabracidae), and is characterized by the many distinct black spots on the bodies of mature fish. For the first time, six specimens have been recorded in Quang Ninh province. The specimens were collected from Luon Cave in Bai Tu Long National Park in May-June 2019. The new specimens collected from Quang Ninh, Vietnam are different from the recorded specimens from Japan, Korea, Taiwan, and China in terms of lateral line scales (LLS) as the samples collected in Quang Ninh, Vietnam have 94-97 scales and the samples collected from the other countries have 66-82 scales. Phylogenetic analysis of the 16S rDNA sequence confirmed that all of the samples collected in Quang Ninh, Vietnam belonged to the species of spotted sea bass.

Agricultural field wastes contain a large amount of active chemicals in the form of pesticide residues. However, treatment of these active chemicals is still weak since a more complex process is required. This study aimed to extract pesticide residues from field waste bags using baking soda (NaHCO3), acetic acid (CH3COOH), and a cleaning solution, and then remove the pesticides from the wastewater by the photo-Fenton reaction. The pesticide bags were collected from intensive paddy fields in Hanoi. The research was conducted on samples of selected fungicides, insecticides, and herbicides. The results showed that a 1% NaHCO3 solution had an optimal extraction performance and obtained a high rate of COD after 15 minutes of exposure, followed by CH3COOH and the cleaning solvent. The extraction process under the photo-Fenton reaction was enhanced by circulation (25 liters per min) and aeration (60 liters per minute). It was found that alanine, carbaryl, and carbamate were in the extracted solutions. The removal efficiency by the photo-Fenton reactions with 254nm UV light at pH around 3.0 increased from 64% to 92% for these residues when the ratio of Fe2+/H2O2 increased from 1:5 to 1:15. This study shows a potential pesticide treatment from field waste bags by photo-Fenton reactions to reduce negative impacts on the environment and ecosystem.

The ftsZ proteins have been well-characterized to play a crucial role in the cell division. Here, we reported a comprehensive analysis of the ftsZ proteins in Bacillus and Lactococcus genus groups by the bioinformatics approaches. As the results, we identified and characterized ftsZ proteins in 19 Bacillus and 22 Lactococcus species. The sizes and weights of the ftsZ proteins in Bacillus and Lactococcus genus groups ranged from 376 to 410 aa residues, 387 to 430 aa residues, and from 39.53 to 44.15 kDa, 41.14 to 45.11 kDa, respectively. All ftsZ proteins in Bacillus and Lactococcus species were acidic and globular and localized in the cytoplasm. Next, the 3D model and multiple alignments have been performed. We realized that the ftsZ proteins in Bacillus and Lactococcus species exhibited five specific regions. Taken together, our study could provide a general background for further functional characterization of the ftsZ proteins in Bacillus and Lactococcus species.

The research focused on evaluating the economic efficiency of swine farms applying biosecurity practices in Bac Ninh Province. Our study surveyed 143 pig farms in Bac Ninh province. The ordinal logit regression model was employed to estimate the factors affecting the level of biosecurity practices. Moreover, the semi-log regression model was used to examine the influence of some factors affecting the profitability of pig farms. The results showed that biosecurity practices had a significant impact on the economic efficiency of livestock farms by helping livestock farms increase their economic efficiency, reducing the mortality rate of animals, and reducing the rate of abandonment of farms.  The factors affecting the level of biosecurity application on the farms included the gender, experience, and education of the farm owner, and the livestock scale. The results aslo expressed a negative relationship between the economic efficiency of the farm and seeding costs, electricity and water costs, feeding costs, labor costs, and veterinary medicine costs, and a positive relationship between the economic efficiency and selling price as well as between the livestock scale and biosecurity application. Finally, some appropriated solutions could be recommended for the improvement of the economic efficiency of swine farms applying biosecurity practices.

H'Mong cattle are considered to have several advantages over other local Yellow cattle in Vietnam, serving as a valuable livestock genetic resource. This breed is not only a primary livelihood but also a source of pride deeply tied to the cultural identity of the H'Mong people. Several research and development projects have been undertaken to utilize this cattle breed. This paper reviews available research findings to provide an overview of the breed’s origins, actual strengths and weaknesses, and proposes sustainable solutions for its utilization.