Farms In Vietnam Research Articles

Evaluating the impact of the government loan program on farms in Vietnam: An application of fuzzy regression discontinuity design

AbstractThis study examines the role of a government loan program on the performance of agricultural, forestry, and fishery farms in Vietnam, utilizing a fuzzy regression discontinuity design. The results of the study indicate that: (i) the government loan program decreases the total revenue of participating farms and (ii) the heterogeneous impact of the loan program depends on the type of farm (e.g., nonlivestock farms tend to receive more positive effects from the loan program). Notably, the study reveals some mechanisms explaining why having government loans can reduce farm efficiency; specifically, farms that use more pesticides and do not engage in e‐commerce activities tend to suffer from the government loan program. The results of the study have important implications for future research, particularly in improving the effectiveness of government loan programs and promoting formal e‐commerce activities in the future.

Isolation and genetic characterization of waterfowl parvovirus in ducks in Northern Vietnam.

Short beak and dwarfism syndrome (SBDS), a highly contagious disease, has been reported in duck farms in Vietnam since 2019. In this study, we evaluated the virulence and characterized the virus obtained from SBDS cases in North Vietnam. Polymerase chain reaction was used to detect waterfowl parvovirus in ducks, and the virus from positive samples was inoculated into 10-day-old duck-embryonated eggs to reproduce the disease in young ducklings to determine the virulence and subjected to phylogenetic analysis of non-structural (NS) and VP1 gene sequences. Goose parvovirus (GPV) was isolated from ducks associated with SDBS in Vietnam. The virus Han-GPV2001 is highly virulent when inoculated into 10-day-old duck embryos and 3-day-old ducklings. The mortality rate of duck embryos was 94.35% within 6 days of virus inoculation. Inoculating 3-day-old ducks with the virus stock with 104.03 EID50 through intramuscular and neck intravenous administration resulted in 80% and 66.67% of clinical signs of SDBS, respectively, were shown. Phylogenetic analysis based on the partial NS and VP1 gene sequences revealed that the viral isolate obtained in this study belonged to novel GPV (NGPV) and was closely related to previous Vietnamese and Chinese strains. A GPV strain, Han-GPV2001, has been successfully isolated and has virulence in duck-embryonated eggs as well as caused clinical signs of SBDS in ducks. Phylogenetic analyses of partial genes encoding NS and capsid proteins indicated that the obtained GPV isolate belongs to the NGPV group.

Agricultural transformation: A story about the Internet of Things

Precision agriculture, a sustainable solution for enhancing crop productivity, utilizes enabling technologies, primarily centred around the Internet of Things (IoT), to optimize irrigation and increase crop yields by adapting farming techniques to specific conditions. This study presents the adoption of a low-cost and eco-friendly IoT initiative in rural farms in Vietnam, which is an unexpected location. It marks the country’s first IoT start-up for agriculture during the 4.0 Industrial Revolution. To answer three research questions, we conducted a contemporary case study mixed with a couple of field experiments in a real-life context to learn how an IoT application was blended with local culture to transform traditional agriculture to a modern and digitalized industry. The pilot implementation yielded promising results, with positive feedback from farmers. Following necessary modifications, the system has been widely adopted across provinces in Vietnam. The study identified three key factors contributing to the start-up’s success: ‘Thiên thời, Địa lợi, Nhân hòa’. We believe that the start-up can assist millions of local farmers to get on the 4.0 train and that adopting IoT to initiate smart agriculture in Vietnam has sent a strong message ‘To be successful, global technology has to integrate into local culture’.

Economic assessment of an intervention strategy to reduce antimicrobial usage in small-scale chicken farms in Vietnam

Antimicrobials are a core aspect of most livestock production systems, especially in low-and middle-income countries. They underpin the efficient use of scarce feed resources and stabilize returns on capital and labor inputs. Antimicrobial use (AMU) contributes to the production of healthy animals, yet AMU in livestock is linked to antimicrobial resistance (AMR) in animals, humans and the environment.The Vietnamese Platform for Antimicrobial Reduction in Chicken Production was implemented during 2016–2019 and was one of Southeast Asia's first interventions focused on AMU reductions in livestock production. The project targeted small-scale commercial poultry farms in the Mekong Delta region of Vietnam using a “randomized before-and-after controlled” study design. It provided farmers with a locally adapted support service (farmer training plan, advisory visits, biosecurity, and antimicrobial replacement products) to help them reduce their reliance on antimicrobials. A partial budget analysis was performed comparing the control group (status-quo) and intervention group (alternative). The median net farm-level benefit of the intervention strategies with the project's support was VND 6.78 million (interquartile range (IR) VND -71.9–89 million) per farm. Without project support the benefit was reduced to VND 5.1 million (IR VND -69.1–87.2 million) to VND 5.3 million (IR -VND 68.9–87.5 million) depending on the antimicrobial alternative product used. At the project level with a focus on AMU and its reduction, subsequently influence on the resistance reduction, our results showed that achieving resistance reduction benefits with the current knowledge and technologies required investment of at least VND 9.1 million (US$ 395.10) per farm during the project's lifetime. The results highlight the positive net profit for the majority of enrolled farms and a reasonable investments from the project. The recommendation focuses on the implementation of policies on financial support, legislation, and information as potential solutions to facilitate the application of intervention strategies to reduce AMU in poultry production.

PREVALENCE OF BOVINE MASTITIS AND THE FIRST DETECTION OF MYCOPLASMA BOVIS IN VIETNAM’S DAIRY FARMS

Mastitis still remains an economic disease in dairy farms all over the world. This study aimed to report the prevalence of this disease in large-scale farms in Vietnam, the pathogens profile, and first report the detection of Mycoplasma bovis (M. bovis) by applying conventional culture and real-time PCR (polymerase chain reaction) methods. We examined 64,802 enrolled dairy cows from six farms in Vietnam, yielding 1,874 (2.9%) total cases of clinical mastitis. The majority of the 14 pathogens were identified. Klebsiella spp. accounted for 21.0% of the total isolates. Streptococcus uberis (S. uberis), Escherichia coli (E. coli), other Streptococcus spp, and Coagulase-Negative Staphylococci (CNS), followed at 12.6, 7.6, 6.0, and 5.5 percent, respectively. The rest pathogens include Pseudomonas spp., Enterococcus faecalis, Enterobacter spp., Bacillus spp., Citrobacter spp., Pasteurella spp., Proteus spp., and Staphylococcus aureus were isolated with less than 1% each. To the best of our knowledge, this is the first report for detecting M. bovis in mastitis milk samples in Vietnam, where 35 out of 1,422 samples submitted in 2022 were M. bovis positive. Moreover, of the 35 positive cases, 11 cases had only M. bovis, while 24 cases had M. bovis and other pathogens, including 13 Enterobacteriaceae, 7 Streptococcus spp., and 4 CNS.

Economic and Environmental Performance of Farms in Vietnam: Does Contract Farming Matter?

Economic and Environmental Performance of Farms in Vietnam: Does Contract Farming Matter?

Knowledge, Attitude, and Practices of Swine Farmers related to Livestock Biosecurity: A Case Study of African Swine Fever in Vietnam

Purpose: African Swine Fever (ASF), one of the world’s most contagious and deadly livestock infectious diseases, was introduced to Vietnam in 2019 and has since become one of the biggest threats to the country’s porcine industry. To this day, very little is known about the major drivers of ASF outbreaks – in particular, the generally low levels of biosecurity found on smallholder farms in Vietnam. The main objective of this paper is to assess the knowledge disparities, diverging attitudes, and different practices among smallholder pig farming households that influence the adoption, implementation, and continuation of ASF biosecurity measures in Vietnam. Research Method: Structured questionnaire surveys were conducted to 183 smallholder pig farming households in December 2020 in four districts of Dong Nai, the largest pig production province in Vietnam. The determinants of farmers’ knowledge and attitude toward ASF were estimated using an ordinal probit regression; a panel-data probit regression approximated the probability of farmers adopting biosecurity measures. Findings: It was found that, prior to the first outbreaks of ASF in Vietnam in 2019, surveyed pig farmers generally had an inadequate level of knowledge about ASF to be able to successfully prevent and control the disease’s spread. Rather, farmers only managed to significantly improve their understanding of ASF after outbreaks had begun. Model estimates indicate that a better understanding of ASF ultimately helped improve farmers’ attitudes toward ASF biosecurity measures. Additionally, farmers with previous experience in dealing with other livestock infectious disease outbreaks were, in most cases, found to be more willing to implement ASF biosecurity measures. Together, deeper understanding of ASF and more positive attitudes towards ASF prevention and control measures contributed to an overall increase in the likelihood of farmers adopting and implementing appropriate ASF biosecurity practices. Originality/ Value: This paper highlights the need for improved community education campaigns in efforts to prevent and contain ASF outbreaks, as well as the need for increased financial assistance and support for swine farmers to enable them to adopt effective biosecurity practices.

Understanding vulnerability and resilience of Vietnamese pangasius farming in the context of the Covid-19 pandemic

In Vietnam, pangasius farming has developed rapidly in the past decades, with the aquaculture of this particular fish species proving to be very beneficial for the local economy. However, the emergence and spread of the Covid-19 pandemic and the policy responses in slowing the spread of the virus have significantly impacted the sector. This paper investigates both the vulnerability and resilience of pangasius aquaculture by identifying the various impacts of the Covid-19 pandemic on Vietnam's pangasius sector and the subsequent responses of this sector towards the issues brought forward by it. In this paper, data collected from 195 pangasius farms in Vietnam are operationalized via binary and ordinal logistic regression in an attempt to reveal the factors affecting the sector's output and the factors driving farmers' responses in the context of insecurity caused by the Covid-19 pandemic. Since the emergence of the pandemic-induced shock on the pangasius sector, farmers have encountered difficulties regarding the sale of harvests and have been confronted with lower prices for pangasius products, with the sector reporting a reduction in the sales volume and the number of buyers, as well as farmers facing disruptions in logistics and input accessibility. As a response to the impacts of the pandemic, pangasius farmers resorted to a number of coping strategies including feeding pangasius less, reducing the farming scale, delaying harvesting, and/or releasing smaller sized fingerlings. Our regressions suggest that farms signing contracts with buyers are more resilient to the reduction in output price and the reduction in number of buyers but, on the other hand, these farms seem to be more severely impacted by the adverse impacts of reduced sales volume, higher feed price and difficulty to sell harvest compared to those without contracts. Furthermore, our findings suggest that farms selling products to export traders suffered more severely from the reduction in the price of pangasius products and in the number of buyers but, at the same time, these farms seemed to have fewer problems with the reduced sales volume and the increased feed price. Interestingly, our findings also suggest a cross-vulnerability with climate change, specifically with respect to the increase in feed price and the disruption in input logistics, hereby further increasing the vulnerability of pangasius farmers.

Prevalence and Associated Factors of optrA-Positive-Enterococcus faecalis in Different Reservoirs around Farms in Vietnam.

Linezolid is an antibiotic of last resort for the treatment of infections caused by Gram-positive bacteria, including vancomycin-resistant enterococci. Enterococcus faecalis, a member of enterococci, is a significant pathogen in nosocomial infections. E. faecalis resistance to linezolid is frequently related to the presence of optrA, which is often co-carried with fex, phenicol exporter genes, and erm genes encoding macrolide resistance. Therefore, the common use of antibiotics in veterinary might promote the occurrence of optrA in livestock settings. This is a cross-sectional study aiming to investigate the prevalence of optrA positive E. faecalis (OPEfs) in 6 reservoirs in farms in Ha Nam province, Vietnam, and its associated factors and to explore genetic relationships of OPEfs isolates. Among 639 collected samples, the prevalence of OPEfs was highest in flies, 46.8% (51/109), followed by chickens 37.3% (72/193), dogs 33.3% (17/51), humans 18.7% (26/139), wastewater 16.4% (11/67) and pigs 11.3%, (14/80). The total feeding area and total livestock unit of the farm were associated with the presence of OPEfs in chickens, flies, and wastewater. Among 186 OPEfs strains, 86% were resistant to linezolid. The presence of optrA was also related to the resistant phenotype against linezolid and levofloxacin of E. faecalis isolates. Close genotypic relationships identified by Pulsed Field Gel Electrophoresis between OPEfs isolates recovered from flies and other reservoirs including chickens, pigs, dogs, and wastewater suggested the role of flies in the transmission of antibiotic-resistant pathogens. These results provided warnings of linezolid resistance although it is not used in livestock.

Technology costs for the first wave of wind farms in Vietnam: Paying extra for better wind nearshore

Technology analysts often dichotomize wind power projects as onshore vs offshore. They neglect nearshore projects installed in the intertidal flats. We explore the characteristics of this intermediate category using an original sample of Vietnam's wind power projects for the 2018–2021 period. The median investment for onshore wind power projects in Vietnam is 1695 USD/kW. It is 2011 USD/kW for nearshore projects. Nearshore wind-power generation capacity requires about 20 % more investment per MW than onshore, inter-quartile range of 0 % – 45 %. Nevertheless, nearshore projects remain much less capital-intensive than far-offshore projects – projected at 3150 USD/kWh in Vietnam based on experience in OECD countries with fixed-bottom projects. Escaping the onshore vs offshore dichotomy allows us to consider a different policy direction for the industry. Rather than pursuing bluefield mega-projects far offshore, a “small steps” policy to extend nearshore wind farms may be cheaper, faster, and more institutionally feasible.

Modeling the accuracy of a novel PCR and antibody ELISA for African swine fever virus detection using Bayesian latent class analysis.

Diagnostic test evaluation for African swine fever (ASF) in field settings like Vietnam is critical to understanding test application in intended populations for surveillance and control strategies. Bayesian latent class analysis (BLCA) uses the results of multiple imperfect tests applied to an individual of unknown disease status to estimate the diagnostic sensitivity and specificity of each test, forgoing the need for a reference test. Here, we estimated and compared the diagnostic sensitivity and specificity of a novel indirect ELISA (iELISA) for ASF virus p30 antibody (Innoceleris LLC.) and the VetAlert™ ASF virus DNA Test Kit (qPCR, Tetracore Inc.) in field samples from Vietnam by assuming that disease status 1) is known and 2) is unknown using a BLCA model. In this cross-sectional study, 398 paired, individual swine serum/oral fluid (OF) samples were collected from 30 acutely ASF-affected farms, 37 chronically ASF-affected farms, and 20 ASF-unaffected farms in Vietnam. Samples were tested using both diagnostic assays. Diagnostic sensitivity was calculated assuming samples from ASF-affected farms were true positives and diagnostic sensitivity by assuming samples from unaffected farms were true negatives. ROC curves were plotted and AUC calculated for each test/sample combination. For comparison, a conditionally dependent, four test/sample combination, three population BLCA model was fit. When considering all assumed ASF-affected samples, qPCR sensitivity was higher for serum (65.2%, 95% Confidence Interval [CI] 58.1-71.8) and OF (52%, 95%CI 44.8-59.2) compared to the iELISA (serum: 42.9%, 95%CI 35.9-50.1; OF: 33.3%, 95%CI 26.8-40.4). qPCR-serum had the highest AUC (0.895, 95%CI 0.863-0.928). BLCA estimates were nearly identical to those obtained when assuming disease status and were robust to changes in priors. qPCR sensitivity was considerably higher than ELISA in the acutely-affected population, while ELISA sensitivity was higher in the chronically-affected population. Specificity was nearly perfect for all test/sample types. The effect of disease chronicity on sensitivity and specificity could not be well characterized here due to limited data, but future studies should aim to elucidate these trends to understand the best use of virus and antibody detection methods for ASF. Results presented here will help the design of surveillance and control strategies in Vietnam and other countries affected by ASF.

Aeromonas hydrophila ST251 and Aeromonas dhakensis are major emerging pathogens of striped catfish in Vietnam.

Aeromonads are ubiquitous in aquatic environments and several species are opportunistic pathogens of fish. Disease losses caused by motile Aeromonas species, particularly Aeromonas hydrophila, can be challenging in intensive aquaculture, such as at striped catfish (Pangasianodon hypophthalmus) farms in Vietnam. Outbreaks require antibiotic treatments, but their application is undesirable due to risks posed by resistance. Vaccines are an attractive prophylactic and they must protect against the prevalent strains responsible for ongoing outbreaks. This present study aimed to characterize A. hydrophila strains associated with mortalities in striped catfish culture in the Mekong Delta by a polyphasic genotyping approach, with a view to developing more effective vaccines. During 2013-2019, 345 presumptive Aeromonas spp. isolates were collected at farms in eight provinces. Repetitive element sequence-based PCR, multi-locus sequence typing and whole-genome sequencing revealed most of the suspected 202 A. hydrophila isolates to belong to ST656 (n = 151), which corresponds to the closely-related species Aeromonas dhakensis, with a lesser proportion belonging to ST251 (n = 51), a hypervirulent lineage (vAh) of A. hydrophila already causing concern in global aquaculture. The A. dhakensis ST656 and vAh ST251 isolates from outbreaks possessed unique gene sets compared to published A. dhakensis and vAh ST251 genomes, including antibiotic-resistance genes. The sharing of resistance determinants to sulphonamides (sul1) and trimethoprim (dfrA1) suggests similar selection pressures acting on A. dhakensis ST656 and vAh ST251 lineages. The earliest isolate (a vAh ST251 from 2013) lacked most resistance genes, suggesting relatively recent acquisition and selection, and this underscores the need to reduce antibiotics use where possible to prolong their effectiveness. A novel PCR assay was designed and validated to distinguish A. dhakensis and vAh ST251 strains. This present study highlights for the first time A. dhakensis, a zoonotic species that can cause fatal human infection, to be an emerging pathogen in aquaculture in Vietnam, with widespread distribution in recent outbreaks of motile Aeromonas septicaemia in striped catfish. It also confirms vAh ST251 to have been present in the Mekong Delta since at least 2013. Appropriate isolates of A. dhakensis and vAh should be included in vaccines to prevent outbreaks and reduce the threat posed by antibiotic resistance.

Polymerase chain reaction-based detection of coinfecting DNA viruses in Vietnamese pigs in 2017 and 2021.

Many studies have reported on the phenomenon of co-infections involving two or more pathogens (bacteria or viruses) over the past few years. However, very few studies on this issue were conducted in Vietnam. Therefore, this study aimed to determine the circulation of single and multiple porcine parvovirus (PPV) (e.g., PPV1, PPV2, PPV3, and PPV4), porcine bocavirus (PBoV), and torque teno virus (TTV) (TTV1 and TTV2) infections in Vietnamese pigs. A total of 174 porcine circovirus 2-positive samples from pigs (n = 86 for 2017 and n = 88 for 2021), including from the sera and internal organs, across 11 provinces were examined by polymerase chain reaction. This study demonstrated the wide distribution of DNA viruses among pig farms in Vietnam in 2021, with the detection rate for PPV ranging from 3.4% to 27.3% among PPV1-PPV4. Moreover, the detection rates of TTV genotypes were confirmed to be 14.8% (TTV1) and 63.6% (TTV2), respectively, and the positive rate of PBoV was 65.9%. The most frequent combinations were double and triple infections. Double infection was found in 16/86 (18.6%) in 2017 and 26/88 (29.5%) in 2021, while triple infection was found at 19/86 (22.1%) in 2017 and 26/88 (29.5%) in 2021. The incidence of simultaneous detection of more than three viruses was low. These results provide at least partial information about the occurrence of three viruses, including PPV (including PPV1 to 4), PBoV, and TTV (TTV1 and TTV2), in pigs. Determination of particular viruses in pigs will help to prevent the porcine respiratory disease complex caused by DNA viruses in Vietnamese pigs in the future.

Estimation of basic reproduction number (R0) of African swine fever (ASF) in mid-size commercial pig farms in Vietnam.

African swine fever (ASF) is a devastating disease affecting the global swine industry. Recently, it has spread to many countries in Africa, Europe, Asia, and the Caribbean, leaving severe damage to local, regional, national, and global economies. Due to its highly complex molecular characteristics and pathogenesis, the development of a successful vaccine has been an unmet challenge. Therefore, ASF control relies solely on biosecurity, rapid detection, and elimination. Epidemiological information obtained from natural ASF outbreaks is critical for designing and implementing ASF control measures. Basic reproduction number (R0), an epidemiological metric used to describe the contagiousness or transmissibility of infectious agents, is an important epidemiological tool. In this study, we have calculated R0 for the in-farm spread of ASF among fattening pigs and sows in two midsize commercial pig farms, HY1 and HY2, that practice the spot removal approach in controlling ASF outbreaks in Vietnam. The R0 values for the sows and fattening pigs were 1.78 (1.35–2.35) and 4.76 (4.18–5.38) for HY1 and 1.55 (1.08–2.18) and 3.8 (3.33–4.28) for HY2. This is the first study to evaluate the transmission potential of ASF in midsize commercial pig farms in Vietnam. Based on the R0 values, we predict that the spot removal approach could be used to successfully control ASF outbreaks in midsize commercial sow barns but not in fattening pens.

Multivariate analysis identifying the main factors associated with cow productivity and welfare in tropical smallholder dairy farms in Vietnam

This study aimed to rank potential drivers of cow productivity and welfare in tropical smallholder dairy farms (SDFs) in Vietnam. Forty-one variables were collected from 32 SDFs located in four geographically diverse dairy regions, with eight SDFs per region. Twelve variables, including milk yield (MILK), percentages of milk fat (mFA), protein (mPR), dry matter (mDM), energy-corrected milk yield (ECM), heart girth (HG), body weight (BW), ECM per 100 kg BW (ECMbw), body condition score (BCS), panting score (PS), inseminations per conception (tAI), and milk electrical resistance (mRE) of cows, were fitted as outcome variables in the models. Twenty-one other variables describing farm altitude, housing condition, and diet for the cows, cow genotypes, and cow physiological stage were fitted as explanatory variables. Increased farm altitude was associated with increases in ECM and mRE and with decreases in PS and tAI (P < 0.05). Increases in roof heights and percentage of shed side open were associated with increases in ECM, mFA, and mDM (P < 0.05). Increased dry matter intake and dietary densities of dry matter and fat were associated with increased MILK, ECM, and ECMbw and decreased tAI (P < 0.05). Increased dietary lignin density was associated with increased PS. Increased genetic proportion of Brown Swiss in the herd was associated with increased MILK, ECM, and ECMbw (P < 0.05). Thus, to improve cow productivity and welfare in Vietnamese SDFs, the following interventions were identified for testing in future cause-effect experiments: increasing floor area per cow, roof heights, shed sides open, dry matter intake, dietary fat density, and the genetic proportion of Brown Swiss and decreasing dietary lignin density.

Characterisation of chicken farms in Vietnam: A typology of antimicrobial use among different production systems

Characterisation of chicken farms in Vietnam: A typology of antimicrobial use among different production systems

Smart Agriculture for Small Farms in Vietnam: Opportunities, Challenges and Policy Solutions

Vietnam’s agriculture has gained outstanding achievements such as having a foothold on its food and nutrition security, solving the jobs in the rural areas, its contribution to GDP, etc., but it has also been facing challenges in the context of climate change and disasters. Smart agriculture is a solution for Vietnam and its small farmers to overcome the above difficulties. Smart agriculture helps farmers gain access to complete and timely information, skills, techniques to make better decisions in their production and trading.

Characterisation of chicken farms in Vietnam: A typology of antimicrobial use among different production systems

The usage of antimicrobials in livestock production is a driver for antimicrobial resistance worldwide. Reducing the use of antibiotics in the animal sector is a priority and requires a change in practices. Vietnam has diverse husbandry and antimicrobial use practices. The objective of this study was to determine the socio-economic and technical factors associated with antibiotic usage patterns on chicken farms in the north and south of Vietnam. Semi-structured interviews (n = 34) and on-farm questionnaires (n = 125) were conducted to collect socio-economic, technical, biosecurity, health management, and antibiotic usage data. Using Multivariate Corresponding Analysis, we identified three production systems (A, B, C) and three patterns of antibiotic usage (1, 2, 3). Group A raised indoor exotic chickens in an intensive setting and was associated with group 1, which used antibiotics according to company recommendations for both treatment and prevention. Group C raised free-range chickens for their own consumption and was associated with group 2, which used antibiotics according to drugstore advice for treatment. Finally, group B was a market-oriented, semi-confined system associated with group 3, which practiced experience-based antibiotic use and overuse. Farms in the south of Vietnam were associated with group 3 and those in the north with group 2. The prediction of antibiotic usage patterns based on farming practices could lead to the identification of a group of farms to be targeted in order to foster the more prudent use of antibiotics in Vietnam.

Carriage of Plasmid-Mediated Colistin Resistance-1-Positive Escherichia coli in Humans, Animals, and Environment on Farms in Vietnam.

Plasmid-Mediated Colistin Resistance 1 (mcr-1) was first reported in 2015 and is a great concern to human health. In this study, we investigated the prevalence of mcr-1 and mcr-1-positive Escherichia coli (MCRPEC) and the association in infection status among various reservoirs connected to livestock. The study was conducted in 70 poultry and swine farms in a commune in Ha Nam province, northern Vietnam. Samples were collected from farmers, food animals, domestic animals, and farm environments (flies and wastewater) for polymerase chain reaction (PCR) screening for mcr-1 gene and species identification of PCR positive isolates. Among 379 obtained mcr-1 positives isolates, Escherichia coli was the major identified, varying from 50% (2/4) in dog feces to 100% (31/31) in humans feces isolates. The prevalence of MCRPEC was 14.4% (20/139), 49.7% (96/193), 31.3% (25/80), 36.7% (40/109), 26.9% (18/67), and 3.9% (2/51) in humans, chickens, pigs, flies, wastewater, and dogs, respectively. The study identified association between MCRPEC infection status in humans and flies (OR = 3.4), between flies and chickens (OR = 5.3), and between flies and pigs (OR = 9.0). Farmers' age and farm livestock unit were also associated factors of MCRPEC infection status in humans (OR = 5.1 and 1.05, respectively). These findings bring new knowledge on antibiotic resistance in livestock setting and important suggestions on potential role of flies in the transmission of mcr-1 resistance gene.

Risk Factors for Prolonged Birth Interval in Modern Swine Farms in Vietnam

The present study aimed to investigate factors influencing the prolonged birth interval in swine, defined as a birth interval longer than 30 minutes. In total, 3380 piglets born from 239 Landrace x Yorkshire sows from 5 farms in the North of Vietnam were included in this study. The dependent variable was the prolonged birth interval, and independent variables included parity, gestation length, litter size, relative birth order, crown-rump length, birth weight, body-mass index, ponderal index, piglet’s gender, dead-born piglet, and oxytocin use. Important factors for the prolonged birth interval were determined by using Generalized Linear Mixed Models. The incidence of the prolonged birth interval was 14.5%. Crown-rump length (OR=1.09, 95% CI=1.06-1.14), birth weight (OR=1.06, 95% CI=1.02-1.09), and dead-born piglet (OR=1.98-2.08, 95% CI=1.38-2.97) were positively associated with the prolonged birth interval, while litter size (OR=0.90, 95% CI=0.96-0.94) negatively correlated with the prolonged birth interval. The incidence of prolonged birth interval decreased with an increase in relative birth order, bottoming at relative birth order of 40-80, and then increased to the end of parturition. The last piglets had the highest risk of experiencing prolonged birth intervals. This study indicated that prolonged birth interval in swine was common; therefore, careful farrowing supervision should be practiced to reduce stress in sows and piglets.