Jully Gogoi Tiwari

Bovine viral diarrhea virus (BVDV) is globally endemic, with the ability to establish persistent infection (PI) being central to its complex epidemiology. Currently the genetic variability of BVDV in Bangladesh remains poorly understood. This study involved a survey in commercial dairy herds in the south-eastern part of Bangladesh in 2024/2025. A total of 373 blood samples were collected from cattle in 24 dairy herds. Serum and buffy coat samples were analyzed using antibody-ELISA and RT-qPCR targeting the 5′-UTR region, followed by sequencing. The MDBK cell line was used for virus isolation and biotyping. Herd and animal-level seroprevalences were 83.3% and 15.3%, respectively, while the corresponding viremic rates were 79.2% and 11.0%. Analysis of 41 sequences identified nine distinct BVDV-1 subgenotypes (1a, 1b, 1c, 1d, 1e, 1 k, 1p, 1o, and 1v), with BVDV-1b (41.5%) and BVDV-2a (14.6%) predominating. Additionally, five HoBiPeV-a pestiviruses were detected. Among antigen-positive cattle, 38 (92.68%) were identified as transiently infected and 3 (7.3%) were confirmed as PI. Six (14.6%) and 27 (65.9%) were identified as cytopathic and non-cytopathic biotypes, respectively. Risk factors for BVDV seropositivity included: female sex (OR: 3.0), clinical disease in the past three months (OR: 2.4), crowding (OR: 2.9), and lack of dedicated clothing for farm workers (OR: 5.7). Active infection was associated with calves (OR: 6.2), heifers (OR: 2.3), stunted growth (OR: 3.0), technician-performed artificial insemination (OR: 10.4), and frequent neighboring farm visits (OR: 3.1). This study has provided data crucial for formulating prevention and control strategies against BVDV to safeguard the Bangladeshi dairy industry.

Phenylalanine (Phe), an essential aromatic amino acid, is emerging as a potential biomarker of metabolic and health status in animals. Altered Phe concentrations reflect changes in metabolic, inflammatory, and disease processes. In companion animals, shifts in serum or biofluid Phe have been linked to hepatopathies, inflammatory enteropathies, and neoplastic conditions. In livestock, variations in milk or serum Phe accompany mastitis, metabolic stress, lameness, and other production-related disorders. Evidence for cats, horses, poultry, and aquaculture species remains limited. Interpretation is complicated by analytical variability, small sample sizes, and confounding factors such as diet, stress, and microbiome composition.
Non-invasive sampling of milk, urine, saliva, and breath, shows promise for Phe monitoring across animal species. Advances in multi-omics, particularly metabolomics, proteomics, and microbiome analyses, can clarify mechanisms and support development of composite biomarker panels. This review evaluates current evidence on Phe as a biomarker across species, highlights gaps in research coverage and methodology, and outlines priorities for future work. Expanding studies to underrepresented species, standardizing measurement protocols, and conducting longitudinal research. Addressing these priorities is essential to establish Phe as a robust biomarker, for veterinary diagnostics, health monitoring, and the optimization of animal welfare and production systems.

Background
Carbapenem-resistant Pseudomonas aeruginosa (CRPA) poses a significant threat to human health, with animal feces serving as an important reservoir of antibiotic-resistant bacteria and potentially CRPA. However, data on the prevalence and characteristics of CRPA in animals are still lacking. The pathogenic potential of CRPA from animals is also poorly understood. This study investigated the prevalence of CRPA in animals in China, along with the virulence potential and phylogenetic relationships of CRPA from animals and humans.

Results
The detection rate of CRPA among the 867 animal samples was 5.07%. Notably, multi-drug resistance was observed in 62% of the 50 animal-derived CRPA, significantly higher than the 23 clinical CRPA isolates in this study (p < 0.05). Furthermore, 20% of the CRPA isolates from animals showed resistance to colistin. Mutations in the oprD gene, rather than carbapenemases, were identified as the primary cause of carbapenem resistance. Phylogeographic analysis revealed that PA isolates were disseminated across 47 countries, and the sequence types (STs) exhibited significant diversity. Furthermore, a higher detection rate of animal-derived CRPA simultaneously carrying multiple virulence factors was observed, surpassing the rate in clinical CRPA. Galleria mellonella assays further confirmed that the CRPA from animals and humans exhibited greater pathogenicity than the hypervirulent Klebsiella pneumonia 18,622. Phylogenetic analysis further revealed that the animal hypervirulent CRPA had only a few SNPs with clinical PA from various countries, including our clinical CRPA, indicating the potential of clonal transmission of CRPA between animals and humans.

Conclusion
Our findings reveal that animals could be an important reservoir of hypervirulent CRPA and highlight the potential for zoonotic transmission to humans. The emergence of hypervirulent CRPA in animal feces highlights the significance of developing control measures in animal farming environments from a “One Health” perspective.

Background
Dog-mediated rabies disproportionately affects marginalised and socioeconomically disadvantaged communities. Tea estate (TE) communities in India exemplify one such vulnerable population. Despite their vulnerability, limited research has explored rabies epidemiology within TE settings. This retrospective study uses secondary data to evaluate the incidence of dog bite and their determinants amongst the TE communities in the Udalguri district of Assam state of India.

Methods
Secondary data from 17 to 29 months (January 2022 to May 2024) were retrieved from the hospitals and dispensaries of 11 TE of Udalguri district, Assam. The collected information included dog-bite victims’ demographics and adherence to post-exposure prophylaxis (PEP). Data were analysed using R software, employing descriptive statistics, chi-square tests, odds ratios and mixed-effect logistic regression. Administrative approval was obtained prior to data collection.

Results
A cumulative annual incidence of 11.8 bites per 1,000 individuals was recorded across 11 TE in Udalguri. Children aged ≤15 years accounted for 35% of cases, and dependents were the most affected occupational group (32%). Most exposures involved dogs (66%), and 76% of incidents were bites. Less than half (43%) of victims completed the full PEP regimen of five doses, although 71% received at least three doses. Chi-square analysis indicated that males and children aged ≤ 15 years were more likely to be bitten by dogs compared to other animals than females and the older residents. Children aged ≤ 15 years and non-workers had higher odds of receiving any PEP, while females and children aged ≤ 15 years are more likely to receive at least three doses. In multivariable analysis, females were less likely than males to be bitten by dogs compared to other animals (aOR = 0.4, 95% CI: 0.3–0.7), older individuals had higher odds of completing PEP (aOR = 1.8, 95% CI: 1.2–2.8), and children (≤15 years) were more likely to receive at least three doses of PEP (aOR = 1.9, 95% CI: 1.1–3.3). Temporal analysis showed no clear seasonal pattern, although spikes were observed during winter and monsoon months.

Conclusion
This retrospective study contributes to build the foundation for community-based approach to control dog-mediated rabies in TE by highlighting key epidemiological patterns, demographic vulnerabilities and limitations of the existing intervention implementation delivery among TE communities. We recommend further in-depth investigations to inform the context specific interventions designed to address the unique vulnerabilities, thereby reducing the risk of rabies specifically in tea -estate populations.

Background: This review examined alternative treatments for bovine mastitis, driven by the rising issue of antibiotic resistance that limits the effectiveness of antibiotic therapies. As few new antibiotics are being developed, exploring non-antibiotic options is essential.

Method: Data were gathered by searching five databases, including PubMed, Scopus, Google Scholar, NCBI, and CABI, for articles on alternative treatments for bovine mastitis. Full texts of relevant studies published from 2013 onwards, both in vitro and in vivo, were screened and retrieved. A deductive approach was used to identify key themes from the review. Data were presented using tables and graphs created with R software for visualisation.

Results: Eligible studies included 69 articles tapered from an initial search of 1696 after removing duplicates and irrelevant records. Phytotherapy was found to be the most extensively researched approach, demonstrating significant effectiveness against mastitis pathogens, including multidrug-resistant Staphylococcus aureus, coagulase-negative S. aureus (CoNS), Escherichia coli, different species of Streptococci, though concerns about the degradation of active compounds in milk and variability in natural product composition exist. Bacteriophage therapy also showed promise, with studies indicating its effectiveness and low risk of inducing bacterial resistance. Treatments such as Trisodium citrate, pheromonicin-NM, and lactoferrin therapy exhibited statistically significant results, particularly against biofilm formation, a major challenge in mastitis management. Many of these treatments lacked extensive in vivo validation. The review highlights the geographic concentration of research, predominantly in countries like China and India, and emphasises the need for more standardised protocols to improve comparison across studies.

Conclusion: The review highlighted phytotherapy, followed by bacteriophage therapy, as the next most researched alternative treatment for mastitis, effective against various pathogens despite concerns about compound degradation. Future research should prioritise the long-term effects of these therapies and their real-world effectiveness in enhancing dairy cow welfare and improving productivity in dairy operations.

Bovine mastitis remains one of the most widespread and economically significant diseases affecting the dairy sector in Pakistan. Despite being a leading global milk producer, Pakistan’s dairy industry faces persistent challenges in controlling mastitis, particularly among smallholder farmers with limited access to veterinary care and diagnostic tools. Antibiotics are frequently used to manage mastitis, often without veterinary oversight, contributing to the growing concern of antimicrobial resistance (AMR). The widespread presence of
Staphylococcus aureus
, a biofilm-forming pathogen, further complicates treatment and accelerates resistance development. Pakistan has initiated efforts to address AMR through national action plans. However, gaps remain in surveillance, responsible antibiotic use, and access to affordable alternatives. This review examines the current landscape of bovine mastitis in Pakistan, including its epidemiology, economic impact, therapeutic practices, and AMR trends. It also outlines practical, low-cost recommendations for improving mastitis management and reducing inappropriate use of antibiotics, particularly in rural settings. Addressing these interconnected challenges through locally adapted, sustainable approaches is essential for improving animal health, milk safety, and long-term productivity in Pakistan’s dairy sector, whilst addressing the global challenge of AMR.

Bovine viral diarrhea virus (BVDV) remains a signiicant and highly contagious pathogen that markedly impacts production and reproductive performances of diierent animals worldwide. .is review represents the global epidemiology of BVDV, emphasizing its genetic diversity, prevalence, host range, associated risk factors, diagnostic advancements, and control strategies. A systematic electronic search was performed to retrieve relevant published articles. A total of 248 studies published over the past 26 years (from January 2000 to March 2025) across 69 countries were included. Data showed that BVDV-1 has been detected across all the continents and comprises 25 subgenotypes (1a-1x and Chinese ZM-95), of which the predominant subgenotypes are 1a, 1b, and 1c. Multiple subgenotypes, such as BVDV-1f, 1g, 1h, 1k, 1l, 1r, 1s, 1t, 1u, and 1x, were distinct and circulating in European countries. Additionally, ,ve subgenotypes (2a–2e) of BVDV-2 have been identiied, with BVDV-2a being the most frequently reported in diierent geographical locations. Notably, the emergence of HoBi-like pestivirus subgenotypes (BVDV-3a–3d) has been detected in Russia, Italy, ,ailand, India, and Bangladesh. Overall, the high prevalence of BVDV has been reported in various European (2.9%–87.1%) and Asian countries (0.2%–89.49%). Although cattle are the primary host, BVDV infections have been documented across a wide range of domestic and wild species, including buualo, sheep, goats, deer, bison, yak, camelids (camels, alpacas, and llamas), pigs, and wild boar. While Ag/Ab-ELISA remains a widely used diagnostic method, advanced techniques, such as RT-qPCR, CRISPR-Cas12a, RT-LAMP, and genome sequencing, are utilized for connrmatory identiication and genotyping of BVDV. Introduction of persistently infected (PI) animals into herds, grazing on common pasture, animal movements, mixed farming practices, and unhygienic breeding practices were frequently documented as potential risk factors. Key measures for controlling and eradicating BVDV include culling of PI animals, prophylactic vaccination, and avoiding mixed farming practices.

The bovine viral diarrhea virus (BVDV) infects a wide range of domestic and wild mammals. This review hypothesized that there might be cross-species transmission of BVDV. Therefore, the aim was to explore the BVDV-5′ UTR and N-pro sequence-based evidence to understand host plasticity among different animals. A total of 146 unique BVDV sequences retrieved from GenBank, originating from 12 distinct mammalian species that are submitted from 55 countries, were analyzed. The phylogenetic analysis revealed that all three BVDV species exhibited genetic relatedness infecting diverse animal species. BVDV-1 sequences obtained from cattle, buffalo, and pigs and BVDV-2 and HoBi-like pestivirus sequences from cattle, goats, and sheep showed a genetic resemblance. Surprisingly, cattle and buffalo in China, cattle and yak in Mongolia, cattle and wild boar in Serbia, cattle and deer in Mexico, cattle and alpacas in Canada, goats and pigs in the USA, and sheep and buffalo in Argentina were infected with BVDV-1 within the same county and strongly positioned in the same cluster, indicating potential spillover with host tropism. Moreover, BVDV sequences isolated from various neighboring countries clustered closely, suggesting potential cross-border transmission events. Based on genomic evidence, the BVDV transmission cycle could be depicted, where cattle act as a primary source of infection, while other domestic and wild animals maintain the infection ecology within their habitat due to virus tropism.

Riemerella anatipestifer causes septicemia in waterfowl, especially in ducks worldwide, while it is becoming a threat to chicken farming in China. In this study, a total of 27,136 samples from septicemic chickens and dead embryos were collected in 29 provinces from 2021 to 2024 to characterize the transmission dynamics of R. anatipestifer and guide evidence-based control strategies. A total of 752 R. anatipestifer strains were isolated and identified by PCR, showing rapid geographical expansion (from 10 to 19 provinces) and rapidly increasing isolation rates (from 1.03% to 4.56%), with peaking in winter/spring. Infection shifted toward younger chickens, infection rates in 3–6-week-old white-feathered broilers increased dramatically from 0.99% to 13.24% (mainly leg lesions), while 50-100-day-old layers showed 2.16% salpingitis. Tissue-specific colonization showed high loads in oviducts (21.68%) and hocks (10.89%). Although R. anatipestifer was detected in 20.18% of early “jelly-like embryos,” it was not found in semen/ovarian follicles. Serotyping showed dominance of type 1 (70.82%) and type 10 (15.86%), with 2.83% untypable strains. Alarmingly, R. anatipestifer had a severe resistance to enrofloxacin (91.54%), polymyxin (88.22%), and amikacin (86.10%). As the first large-scale survey of R. anatipestifer in chickens, these findings highlight its cross-species adaptation, vertical transmission risk, and increasing prevalence in young broilers, which contributes to the understanding of the epidemiology of R. anatipestifer in chickens and provides scientific guidance for the treatment and control of the disease.

Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) are vector-borne orbiviruses that pose an emerging threat to livestock, including cattle and sheep. This review summarizes the global distribution, genetic diversity, and key factors driving their spread along with the existing knowledge gaps and recommendations to mitigate their impact. Both viruses cause hemorrhagic disease in susceptible ruminants and are commonly reported in tropical and subtropical regions including North America, Asia, Africa, Oceania, and some parts of Europe. The geographical distribution of these viruses, encompassing 27 BTV and 7 EHDV serotypes, has shifted, particularly with the recent invasion of BTV-3, 4, and 8 and EHDV-8 serotypes in Europe. Several factors contribute to the recent spread of these viruses such as the distribution of virulent strains by the movement of temperature-dependent Culicoides vectors into new areas due to rapid climate change, the reassortment of viral strains during mixed infections, and unrestricted global trade. These diseases cause significant economic impacts including morbidity, mortality, reduced production, high management costs, and the disruption of international trade. Effective prevention and control strategies are paramount and rely on vaccination, vector control using insecticides, and the destruction of breeding sites, husbandry practices including the isolation and quarantine of infected hosts, restriction of animal movement, prompt diagnosis and identification of circulating strains, and effective surveillance and monitoring plans such as the pre-export and post-import screening of semen used for artificial insemination. However, challenges remain with intercontinental virus spread, live vaccines, and the failure of inactivated vaccines to produce protective immunity against dissimilar strains. Significant knowledge gaps highlight the need for a better scientific understanding and a strategic plan to ensure healthy livestock and global food security.