Organization Of Animal Health Research Articles

An Evaluation of the Thermotolerance of Various Formulations of Freeze-Dried and Reconstituted Peste des Petits Ruminant Vaccines

Peste des Petits Ruminants (PPR) disease is widely distributed in Africa. Live attenuated PPR vaccines are produced using approved Nigeria 75/1 and Sungri/96 strains by the World Organisation of Animal Health (WOAH) to control the disease. These PPR vaccines are very efficacious; however, the main challenge is the maintaining of the cold chain during vaccine distribution and delivery. This study evaluated the thermotolerance of freeze-dried and reconstituted PPR Nigeria 75/1 vaccines from vaccine manufacturers using eight stabilizer formulations (lactalbumin hydrolysate and sucrose, sucrose and peptone, Weybridge medium, trehalose, Lactose and N-Z Amine, lactalbumin hydrolysate, sucrose and L glutamine, skimmed milk, and lactalbumin hydrolysate, maltose and gelatine). Aliquots of the reconstituted PPR vaccine batches were titrated after 2, 4, and 6 h of storage at 4 °C and 40 °C. The PPR vaccines were also titrated after storage at 40 °C and 45 °C for 3 and 5 days. The results showed that reconstituted PPR vaccine stabilized with lactalbumin hydrolysate–sucrose promoted tolerance at 40 °C for 6 h. It was also noted that all reconstituted PPR vaccine formulations except the formulation stabilized with lactalbumin hydrolysate–maltose–gelatine maintained the titre above a 102.5 TCID50/dose after 4 h of storage at 4 °C. Furthermore, the results showed that the PPR vaccine formulation containing lactalbumin hydrolysate sucrose was as the only one that maintained the titres above 102.5 TCID50/dose after storage at 45 °C for 5 days, with a titre loss of 100.95 TCID50/dose. Therefore, vaccine manufacturers producing PPR vaccines for use in tropical field regions could preferably use lactalbumin hydrolysate–sucrose stabilizer in vaccine formulation.

Evaluation of candidate data-based welfare indicators for veal calves in Switzerland.

Welfare assessment protocols have been developed for dairy cows and veal calves during the past decades. One practical use of such protocols may be conducting welfare assessments by using routinely collected digital data (i.e., data-based assessment). This approach can allow for continuous monitoring of animal welfare in a large number of farms. It recognises changes in the animal welfare status over time and enables comparison between farms. Since no comprehensive data-based assessment for veal calves is currently available, the purposes of this review are (i) to provide an overview of single existing data-based indicators for veal calves and (ii) to work out the necessary requirements for data-based indicators to be used in a comprehensive welfare assessment for veal calves in Switzerland. We used the Welfare Quality Protocol® (WQ) for veal calves and the Terrestrial Animal Health Code from the World Organisation of Animal Health for guidance throughout this process. Subsequently, routinely collected data were evaluated as data sources for welfare assessment in Swiss veal operations. The four WQ principles reflecting animal welfare, i.e., 'good feeding', 'good housing', 'good health' and 'appropriate behaviour' were scarcely reflected in routinely available data. Animal health, as one element of animal welfare, could be partially assessed using data-based indicators through evaluation of mortality, treatments, and carcass traits. No data-based indicators reflecting feeding, housing and animal behaviour were available. Thus, it is not possible to assess welfare in its multidimensionality using routinely collected digital data in Swiss veal calves to date. A major underlying difficulty is to differentiate between veal calves and other youngstock using routine data, since an identifying category for veal calves is missing in official Swiss databases. In order to infer animal welfare from routine data, adaptations of data collection strategies and animal identification are required. Data-based welfare assessment could then be used to complement on-farm assessments efficiently and, e.g., to attribute financial incentives for specifically high welfare standards accordingly.

First report of Perkinsus marinus occurrence associated with wild Pacific oysters Crassostrea gigas from the west coast of Korea

This study reports the occurrence of Perkinsus marinus associated with wild Pacific oyster (Crassostrea gigas) specimens collected along the west coast of Korea. Confirmation of P. marinus presence was achieved by conventional PCR using World Organization of Animal Health (WOAH)-recommended primers that specifically targeted regions of the rDNA locus (ITS1, 5.8S, and ITS2). Sequencing of 10 samples revealed two distinct sequences differing by a single base pair, indicating potential haplotype variability. One sequence closely resembled the P. marinus strain found in Maryland, USA, whereas the other exhibited divergence, indicative of species diversity in the Korean strain, as was evident from the haplotype network analysis. Further validation involved the Ray’s Fluid Thioglycollate Medium (RFTM) assay, which initially yielded inconclusive results, possibly due to low infection intensity. Subsequently, RFTM and 2 M NaOH assays conducted on the isolates in the present study, cultured P. marinus cells in standard DMEM/F12 medium, and a positive P. marinus strain (ATCC 50509), revealed characteristic hypnospores of P. marinus upon Lugol’s iodine staining. These comprehensive investigations underscore the conclusive confirmation of P. marinus in Korean waters and mark a significant milestone in our understanding of the distribution and characteristics of this parasite in previously unreported regions.

Current and potential use of animal disease data by stakeholders in the global south and north

What cannot be measured will not be managed. The Global Burden of Animal Diseases (GBADs) will generate information on animal disease burdens by species, production system, type and gender of farmer and consumer, geographical region, and time period. To understand the demand for burden of animal disease (BAD) data and how end-users might benefit from this, we reviewed the literature on animal diseases prioritisation processes (ADPP) and conducted a survey of BAD information users. The survey covered their current use of data and prioritizations as well as their needs for different, more, and better information. We identified representative (geography, sector, species) BAD experts from the authors’ networks and publicly available documents and e-mailed 1485 experts. Of 791 experts successfully contacted, 271 responded (34% response rate), and 185 complete and valid responses were obtained. Most respondents came from the public sector followed by academia/research, and most were affiliated to institutions in low- and middle-income countries (LMICs). Of the six ADPPs commonly featured in literature, only three were recognised by more than 40% of experts. An additional 23 ADPPs were used. Awareness of ADDPs varied significantly by respondents. Respondents ranked animal disease priorities. We used exploded logit to combine first, second and third disease priorities to better understand prioritzation and their determinants. Expert priorities differed significantly from priorities identified by the ADDPs, and also from the priorities stated veterinary services as reported in a survey for a World Organisation of Animal Health (WOAH) technical item. Respondents identified 15 different uses of BAD data. The most common use was presenting evidence (publications, official reports, followed by disease management, policy development and proposal writing). Few used disease data for prioritzation or resource allocation, fewer routinely used economic data for decision making, and less than half were aware of the use of decision support tools (DSTs). Nearly all respondents considered current BAD metrics inadequate, most considered animal health information insufficiently available and not evidence-based, and most expressed concerns that decision-making processes related to animal health lacked transparency and fairness. Cluster analysis suggested three clusters of BAD users and will inform DSTs to help them better meet their specific objectives. We conclude that there is a lack of satisfaction with current BAD information, and with existing ADDPs, contributing to sub-optimal decision making. Improved BAD data would have multiple uses by different stakeholders leading to better evidenced decisions and policies; moreover, clients will need support (including DSTs) to optimally use BAD information.

Comparative analysis of tuberculin and defined antigen skin tests for detection of bovine tuberculosis in buffaloes (Bubalus bubalis) in Haryana state, India

BackgroundBovine tuberculosis (bTB) is a chronic disease that results from infection with any member of the Mycobacterium tuberculosis complex. Infected animals are typically diagnosed with tuberculin-based intradermal skin tests according to World Organization of Animal Health which are presently in use. However, tuberculin is not suitable for use in BCG-vaccinated animals due to a high rate of false-positive reactions. Peptide-based defined skin test (DST) antigens have been identified using antigens (ESAT-6, CFP-10 and Rv3615c) which are absent from BCG, but their performance in buffaloes remains unknown. To assess the comparative performance of DST with the tuberculin-based single intradermal test (SIT) and the single intradermal comparative cervical test (SICCT), we screened 543 female buffaloes from 49 organized dairy farms in two districts of Haryana state in India.ResultsWe found that 37 (7%), 4 (1%) and 18 (3%) buffaloes were reactors with the SIT, SICCT and DST tests, respectively. Of the 37 SIT reactors, four were positive with SICCT and 12 were positive with the DST. The results show that none of the animals tested positive with all three tests, and 6 DST positive animals were SIT negative. Together, a total of 43 animals were reactors with SIT, DST, or both, and the two assays showed moderate agreement (Cohen’s Kappa 0.41; 95% Confidence Interval (CI): 0.23, 0.59). In contrast, only slight agreement (Cohen’s Kappa 0.18; 95% CI: 0.02, 0.34) was observed between SIT and SICCT. Using a Bayesian latent class model, we estimated test specificities of 96.5% (95% CI, 92–99%), 99.7% (95% CI: 98–100%) and 99.0% (95% CI: 97–100%) for SIT, SICCT and DST, respectively, but considerably lower sensitivities of 58% (95% CI: 35–87%), 9% (95% CI: 3–21%), and 34% (95% CI: 18–55%) albeit with broad and overlapping credible intervals.ConclusionTaken together, our investigation suggests that DST has a test specificity comparable with SICCT, and sensitivity intermediate between SIT and SICCT for the identification of buffaloes suspected of tuberculosis. Our study highlights an urgent need for future well-powered trials with detailed necropsy, with immunological and microbiological profiling of reactor and non-reactor animals to better define the underlying factors for the large observed discrepancies in assay performance, particularly between SIT and SICCT.

Development of a highly sensitive TaqMan method based on multi-probe strategy: its application in ASFV detection.

The establishment of high sensitive detection method for various pathogenic microorganisms remains constantly concerned. In the present study, multi-probe strategy was first systematically investigated followed by establishing a highly sensitive TaqMan real-time fluorescent quantitative PCR (qPCR) method for detecting African swine fever virus (ASFV). Briefly, four probes based on the B646L gene of ASFV were designed and the effects of different combinations of the probes in a single TaqMan qPCR assay on the detection sensitivity were investigated. As less as 0.5-5 copies/μl of the ASFV gene was detected by the established TaqMan qPCR assay. Furthermore, plasmid harboring the B646L in water samples could be concentrated 1000 times by ultrafiltration to enable a highly sensitive detection of trace viral nucleic acids. Moreover, no cross-reactivity was observed with other common clinical swine viruses such as PCV2, PCV3, PCV4, PEDV, PDCoV, CSFV, PRRSV, and PRV. When detecting 173 clinical porcine serum samples, the coincidence rate between the developed method and WOAH (World Organization of Animal Health) recommended method was 100%. This study might provide an integrated strategy to achieve higher detection sensitivity of trace pathogenic microorganisms and applicably sensitive TaqMan-based qPCR assays.

Development of a Real-Time qPCR Method for the Clinical Sample Detection of Capripox Virus.

Capripox viruses (CaPVs), including sheep pox virus (SPV), goat pox virus (GPV), and lumpy skin disease virus (LSDV), are the cause of sheep pox (SPP), goat pox (GTP), and lumpy skin disease (LSD) in cattle. These diseases are of great economic significance to farmers, as they are endemic on farms and are a major constraint to international trade in livestock and their products. Capripoxvirus (CaPV) infections produce similar symptoms in sheep and goats, and the three viruses cannot be distinguished serologically. In this study, we developed a real-time quantitative polymerase chain reaction (qPCR) method for identifying CaPV in goats, sheep, and cattle. Clinical samples were tested and verified. The developed assay was highly specific for target viruses, including GPVSPV and LSDV, which had no cross-reaction with other viruses causing similar clinical symptoms. An artificially synthesized positive control plasmid using the CaPV 32 gene inserted into the vector pMD19-T was used as a template, and the correlation coefficient of the linear regression curve (R2) was 0.9916, the estimated amplification efficiency (E) was 96.06%, and the sensitivity (limit of detection, LOD) was 3.80 copies per reaction. Using the clinical samples as a template, the limit of detection (LOD) was 4.91 × 10-5 ng per reaction (1.60 × 10-5-2.13 × 10-3 ng, 95% confidence interval (CI)), which means that this method was one of the most sensitive detection assays for CaPVs. A total of 85 clinical samples from CaPV-infected animals (goats, sheep, and cattle) and 50 clinical samples from healthy animals were used to test and compare the diagnostic results using the Synergy Brands (SYBR) Green-based PCR method recommended by the World Organization of Animal Health (WOAH). Both diagnostic sensitivity (DSe) (95.8-100%, 95% CI) and diagnostic specificity (DSp) (92.9-100%, 95% CI) results of the real-time quantitative PCR (qPCR) and SYBR Green PCR were 100%, and the kappa value (κ) was 1.0 (1-1, 95% CI). In summary, the assay established based on TaqMan probes was advantageous in high specificity, sensitivity, and general applicability and could be a competitive candidate tool for the diagnosis of CaPV in clinically suspected animals.

Highly pathogenic avian influenza: Considerations for vaccination and implications for international trade. A primary breeder’s perspective. Proceeding of The First International Avian Influenza Summit, University of Arkansas- October 16-17, 2023"

Vaccination against avian influenza requires the assessment of multiple technical, legislative, and trade aspects related to its epidemiology and the country’s veterinary infrastructure, commerce policies, and interests. According to the World Organization of Animal Health (WOAH), vaccination against AI should not preclude a country from eligibility for trade as long as it can prove freedom from natural infection. Importing countries may have policies above the general guidelines offered by WOAH; however. Whether living with the disease for a long(er) time, having to adjust vaccines to better protect against newer avian influenza virus variants or clades, and/or whether there are indemnity incentives available to compensate growers for the losses related to outbreaks, considerations pertaining to the geographic spread of the disease across the country’s territory, the sector(s) of the poultry industry being affected, and whether all alternatives to combat the disease have been explored, and perhaps exhausted, should also be taken into consideration. WOAH’s guidelines for the continuation of trade include zoning that limits restrictions to a geographical area (10 km, county, or state) instead of the entire country. Compartmentalization also offers another approach to the continuation of trade for premises that demonstrate robust biosecurity and management programs backed by testing to demonstrate freedom from infection. Alternatives to avoid or reduce waste products (e.g., meat and eggs) should also be considered according to implications to the risk involved of further spread onto other avian and poultry populations. Considering the fact that the 2.3.4.4b clade has been able to infect a large number of wild bird and mammalian species and, at least for countries where the disease is not endemic in its commercial sectors, vaccinating only poultry, at least in countries with low prevalence and incidence rate would not prevent the spread of the disease amongst that large pool of susceptible animal species. For this latter aspect, perhaps vaccination strategies would be more effective if developed towards mitigating prevalence in the natural reservoirs. This implies developing vaccines capable of being deployed in mass. In the large scheme of things and within the one-health concept, this latter approach may have a larger impact on combatting high pathogenicity avian influenza.

Import Risk Analysis of the Decapod Iridescent Virus 1 (DIV1) Applied in South Korea: Qualitative Risk Review and Institutional Improvement Plans

Decapod iridescent virus 1 (DIV1) is a dangerous new virus that causes mortality to shrimp and crayfish. This virus has been reported in China, which is a major exporter of decapods to South Korea and its neighboring countries, Taiwan and Thailand. This virus can be regarded as a pathogen with a high risk of entry into Korea. Therefore, South Korea has been conducting emergency quarantine for DIV1 since 2020, and in this study, an import risk analysis was performed following the World Organization of Animal Health and domestic laws and regulations to present scientific grounds and validity for South Korea’s DIV1 emergency quarantine. Import risk analysis was performed by hazard identification, entry assessment, exposure assessment, and consequence assessment. As a result of the import risk analysis, it was confirmed that the current DIV1 quarantine can significantly reduce the import risk. However, it was also established that the management of prawns and polychaetes intended for animal feed or bait and currently not subjected to quarantine is also required. Additionally, two species of crabs that would meet the criteria for a completely susceptible species and two species of crayfish that required surveillance of the import amount or route of exposure were also identified. In conclusion, these uses and susceptible species were designated as quarantine targets for nonhuman consumption requiring risk management and import sanitary conditions to be performed before export and after import. Finally, alternatives to reduce the cost burden of stakeholders following the introduction of the system were also presented.

Detection and identification of foot-and-mouth disease O/ME-SA/Ind-2001 virus lineage, Indonesia, 2022

ABSTRACT Foot-and-mouth disease (FMD) is a contagious disease affecting cloven-hoofed animals, which has been well-documented as one of the major animal diseases that causes severe economic loss in livestock sectors. The disease is endemic in many countries, particularly in Asia and Africa. Indonesia has been declared a disease-free country since 1986, and the World Organization of Animal Health (WOAH/OIE) recognized Indonesia as an FMD-free country without vaccination in 1990. However, the FMD virus was detected in many disease outbreaks in cattle and goats in Indonesia in May 2022. This study reports the detection and identification of FMD serotype O viruses in Indonesia. Although these viruses appeared to belong to the ME-SA/Ind-2001e lineage, they formed a unique cluster with 95.3% average nucleotide sequence similarity of the FMD VP1 gene to Ind-2001e viruses from other Asia countries. The illegal trade of live animals from endemic areas in Southeast Asia is one of the possible routes regarding the incursion of FMD in Indonesia, however, it requires further investigation.

Retrospective Analysis of Official Data on Anthrax in Europe with a Special Reference to Ukraine.

Anthrax is an acute infectious zoonotic disease caused by Bacillus anthracis that mostly affects grazing livestock and wildlife. Furthermore, B. anthracis is considered one of the most important biological agents of bioterrorism that could also be potentially misused in biological weapons. The distribution of anthrax in domestic animals and wildlife in Europe with a particular focus on Ukraine as a country of war was analyzed. Between 2005 and 2022, 267 anthrax cases were registered at the World Organization of Animal Health (WOAH) in animals in Europe, including 251 cases in domestic animals and 16 in wildlife. The highest numbers of cases were recorded in 2005 and 2016 followed by 2008, and the highest numbers of registered cases were reported from Albania, Russia, and Italy. In Ukraine, anthrax is currently a sporadic infection. Since 2007, 28 notifications were registered, with isolates mainly from soil samples. The highest number of confirmed anthrax cases was registered in 2018, and Odesa, which is close to Moldova, had the highest number of cases, followed by the Cherkasy region. The presence of thousands of biothermal pits and burial grounds of fallen cattle nationwide favors the re-emergence of new foci. Most confirmed cases were in cattle; however, single cases were confirmed in dogs, horses, and pigs. Further investigation of the disease in wildlife and in environmental samples is needed. The genetic analysis of isolates, investigation of susceptibility to antimicrobial compounds, and determination of virulence and pathogenicity factors are required in this volatile region of the world for awareness raising and preparedness.

Cuticular Swabs and eDNA as Non-Invasive Sampling Techniques to Monitor Aphanomyces astaci in Endangered White-Clawed Crayfish (Austropotamobius pallipes Complex)

In endangered crayfish conservation projects, it is paramount to map the distribution of the causative agent of crayfish plague, Aphanomyces astaci, in native populations. Considering the inapplicability of the destructive cuticular sampling protocol for monitoring endangered populations, we explored the use of non-invasive sampling techniques to detect this pathogen with molecular assays. In the present study, we exploited environmental DNA (testing increasing water volumes combined with different filter porosities) and cuticular swabs to collect A. astaci DNA. In addition, we evaluated the impact of the storage method on DNA preservation during field activities. After the first evaluations performed on both highly infected Austropotamobius pallipes and carrier Procambarus clarkii specimens in laboratory conditions, these sampling techniques were applied to wild populations of white-clawed crayfish. Our findings highlight better results with the filtration of 5 L of water with filters of 2.7 µm porosity for eDNA analysis and demonstrate that cuticular swabbing is equally effective as the World Organisation of Animal Health’s protocol. Storage in absolute ethanol proved to be the best solution to preserve swabs and filter samples for up to a week at room temperature. In conclusion, we suggest an integration of both sampling methods when monitoring A. astaci for conservation purposes.

IETS management of the challenges associated with embryo pathogen interaction

One of the very first challenges the International Embryo Transfer Society (IETS) addressed was concern about disease transmission via the transfer of in vivo–derived (IVD) bovine embryos. IETS commissioned its Import/Export Committee, later named Health and Safety Advisory Committee (HASAC), to resolve this matter, with the assistance of the Data Retrieval Committee following its formation in 1991. Since its first meeting in 1984, considerable achievements have been made, including meeting the numerous challenges created by the many innovations in this industry. Based on research studies and their designs, the IETS HASAC developed a system for categorising pathogens and diseases potentially susceptible to interaction with IVD embryos. This has been instrumental in defining safe operating protocols and ultimately leading to the development of the now universally accepted techniques for certification of embryo health. The close cooperation of IETS/HASAC with the World Organization of Animal Health (WOAH, formerly OIE) has facilitated the establishment of guidelines for regulators worldwide, thus ensuring the safety of international trade with embryos, while avoiding unjustified regulatory measures. In addition, IETS/HASAC produced and published the IETS Manual: A Procedural Guide and General Information for the Use of Embryo Transfer Technology Emphasising Sanitary Procedures for the embryo transfer industry (1st edition, 1987; 5th edition, 2023). This manual and its updates were designed to provide the industry world-wide with a source of information on safe and sanitary handling procedures for embryos, to describe the procedures necessary to ensure that the transfer of embryos does not result in transmission of pathogenic agents or disease, and to ensure consistent and accurate identification of embryos. The result of these 40 years of IETS/HASAC involvement is that embryo transfer technology is recognised as having a comparative advantage in international movement of germplasm.

Point-of-Care Testing for Sensitive Detection of the African Swine Fever Virus Genome.

African swine fever (ASF) is a contagious viral hemorrhagic disease that affects domestic pigs and wild boar. The disease is notifiable to the World Organization of Animal Health (WOAH), and causes significant deaths and economic losses. There is currently no fully licensed vaccine available. As a result, early identification of the causative agent, ASF virus (ASFV), is crucial for the implementation of control measures. PCR and real-time PCR are the WOAH-recommended standard methods for the direct detection of ASFV. However, under special field conditions or in simple or remote field laboratories, there may be no sophisticated equipment or even stable electricity available. Under these circumstances, point-of-care systems can be put in place. Along these lines, a previously published, rapid, reliable, and electricity-free extraction method (TripleE) was used to isolate viral nucleic acid from diagnostic specimens. With this tool, nucleic acid extraction from up to eight diagnostic samples can be realized in one run in less than 10 min. In addition, the possibility of completely omitting viral DNA extraction was analyzed with so-called direct real-time PCR protocols using ASFV original samples diluted to 1:40 in RNase-free water. Furthermore, three real-time PCR cyclers, developed for use under field conditions (IndiField, Liberty16 and UF-300 GenecheckerTM), were comparatively applied for the sensitive high-speed detection of ASFV genomes, with overall PCR run times between 20 and 54 min. Depending on the viral DNA extraction/releasing method used and the point-of-care cycler applied, a total time for detection of 30 to 60 min for up to eight samples was feasible. As expected, the limitations in analytical sensitivity were positively correlated to the analysis time. These limitations are acceptable for ASFV diagnostics due to the expected high ASFV genome loads in diseased animals or carcasses.

Taiwan Bat Lyssavirus: In Vitro and In Vivo Assessment of the Ability of Rabies Vaccine-Derived Antibodies to Neutralise a Novel Lyssavirus.

Rabies is a neglected tropical disease. The prototype virus, the rabies virus, still causes tens of thousands of human fatalities annually. Rabies is one member of the genus Lyssavirus. The burden of other lyssaviruses is unclear. The continued emergence of novel lyssaviruses means that assessment of vaccine efficacy against these viruses is critical, as standard rabies vaccines are not efficacious against all lyssaviruses. Taiwan bat lyssavirus (TWBLV) was first reported in 2018 following isolation from Japanese house bats. Since the initial detection and genetic characterisation, no attempts have been made to antigenically define this virus. Due to the inaccessibility of the wildtype isolate, the successful generation of a live recombinant virus, cSN-TWBLV, is described, where the full-length genome clone of the RABV vaccine strain, SAD-B19, was constructed with the glycoprotein of TWBLV. In vitro and in vivo characterization of cSN-TWBLV was undertaken and demonstrated evidence for cross-neutralisation of cSN-TWBLV with phylogroup I -specific sera and rabies virus standard sera. For neutralisation equivalent to 0.5 IU/mL of WHO and World Organisation of Animal Health (WOAH) sera against CVS, 0.5 IU/mL of WOAH sera and 2.5 IU/mL of WHO sera were required to neutralise cSN-TWBLV. In addition, specific sera for ARAV and EBLV-1 exhibited the highest neutralising antibody titres against cSN-TWBLV, compared to other phylogroup I-specific sera.

‘Natural born carers’? Reconstituting gender identity in the labour of calf care

Environmental crises and agricultural policy reforms are key moments for the reorganisation of farming practices, which can contribute to the reconstitution of female farming roles and identities. In this paper, we consider the role of animal disease in providing an opportunity to reconstitute female farming identities, particularly emphasising female farm employees. Focusing on the careers and labour of calf rearers, the paper shows how calf rearing identities are structured and contested, and linked to cultures of care that are shaped by patriarchal farming relations. Drawing on 25 biographical interviews, the paper reveals four distinct narratives of calf rearing: natural born carers, rescue, taking back control, and from outsider to insider. Despite significant changes to the organisation of animal health and welfare for calves, these narratives reveal the marginal status of both calves and calf rearers. Calf rearers’ labour of care encompasses both affectual attachments to calves but also family and farm relationships, reflecting how careful rearing is configured by the material and cultural relations of farming. Whilst some calf rearers have been able to challenge these relationships and reconstitute calf rearing identities, the narratives suggest that calf rearers lack agency to change animal health practices. Awareness of these gendered dimensions to calf rearing and animal health is vital for policy makers seeking to improve the health of livestock.

Validation of an indirect in-house ELISA using synthetic peptides to detect antibodies anti-gp90 and gp45 of the equine infectious anaemia virus.

Equine infectious anaemia (EIA) is controlled by the identification of seropositive animals. The official diagnostic method is the agar gel immunodiffusion (AGID) test, which detects antibodies against a viral core protein (p26). Although AGID is inexpensive and specific, the report of results takes considerable time and the test has low analytical sensitivity. To validate our in-house indirect ELISAgp90/45 , following the World Organization of Animal Health (OIE) criteria. Test validation. Synthetic peptides gp90 and gp45 were used as antigens in ELISAgp90/45 . Tests used for validation, calibration and linear working operating range, analytical and diagnostic sensitivity and specificity, repeatability and reproducibility were assessed by comparing them with the AGID test and using 1844 equine sera grouped into five different panels. We were able to replace the National References Sera with our Internal Reference Sera. ELISAgp90/45 had acceptable repeatability and reproducibility. Analytical sensitivity of the ELISAgp90/45 was 800 times greater than that of AGID test for positive sera and 400 times greater for weak positive sera. ELISAgp90/45 also showed optimal analytical specificity, since no cross-reactivity was detected with antibodies against other equine viruses. One sample was positive by AGID test and negative by ELISAgp90/45. ELISAgp90/45 was performed using 243 EIA positive and 878 negative equid sera, and showed a diagnostic sensitivity of 99.59% [CI 97.73%-99.99%] and a diagnostic specificity of 90.32% [CI 88.17%-92.19%], compared to AGID test; thus, it was demonstrated to be a robust test. Samples were derived from naturally infected equid populations showing heterogeneous clinical states: therefore, their status was uncertain and some horses were sampled more than once. The AGID test may not be the most useful gold standard. ELISAgp90/45 is a useful tool for the diagnosis of EIAV infection and meets validation requirements established by the OIE.

Characterization of a Nigerian Lumpy Skin Disease Virus Isolate after Experimental Infection of Cattle.

Lumpy skin disease virus (LSDV), together with sheeppox virus and goatpox virus, belong to the genus Capripoxvirus within the family Poxviridae. Collectively, they are considered the most serious poxvirus diseases of agricultural livestock. Due to their severe clinical course and consequent loss of production, as well as high mortality of naïve small and large ruminant populations, they are known to have a significant impact on the economy and global trade restrictions of affected countries. Therefore, all capripox diseases are classified as notifiable under the guidelines of the World Organization of Animal Health (OIE). Since the 1970s, several outbreaks of LSD have been recorded in Nigeria. Until now, only a little information on the virus strains leading to the reported outbreaks have been published, dealing mainly with the phylogenetic relationship of those strains and the description of field outbreaks. During the present study, we experimentally infected cattle with a low-passage Nigerian LSDV strain isolated from a skin sample of LSD positive cattle in Nigeria in 2018. Clinical, molecular and serological data indicate that this LSDV isolate is highly pathogenic in cattle since it induced a severe clinical course and approximately 33% mortality in naïve Holstein Friesian cattle after experimental infection.

After SARS-CoV-2, will H5N6 and other influenza viruses follow the pandemic path?

While the world is focused on attending, controlling, and mitigating the current pandemic of COVID-19, caused by the SARS-CoV-2, other viral threats are possibly emerging and reemerging especially in Asia, posing a risk for the spread in that region and beyond. A predictable threat is the avian influenza virus, especially H5N6, which has recently led to significant outbreaks in China and the Philippines, deserving more attention and control. In the current review, we assess the history of this highly pathogenic reemerging virus, as well as the contemporary implications of poultry outbreaks occurring in some Asian countries. We also look at outbreaks due to other strains not only in Asia but also across Europe and Africa, according to recent reports from the World Organization of Animal Health (OIE).

Limit of detection of bacterial contaminant in living bacterial vaccine

A total number of 30 vaccine vials including 3 batches of 3 different types of live bacterial poultry vaccines (Mycoplasma red vaccine, Mycoplasma yellow vaccine and non colored Mycoplasma vaccine) were experimentally contaminated with 1,5,10 CFU of Escherichia coli reference strain (ATCC25992) /dose then subjected for sterility testing as referenced in world organization of animal health(OIE). The sterility is defined as the absence of viable microorganisms, includes viruses. It should be achieved by the use of aseptic techniques and validated sterilization methods, including heating, filtration, chemical treatments and irradiation that fit the intended purpose. Further dilution was carried out of vaccines showing negative results.Kappa index in different contamination levels in all tested vaccines after dilution was ranged between high Kappa index and almost total . In this study , it could be concluded that the applied testing method is appropriate for testing sterility of living bacterial poultry vaccines and it is fit to use