Infected Cattle Research Articles

Human antibodies against Mycobacterium avium ssp. paratuberculosis combined with cytokine levels for the diagnosis and selection of Crohn's disease patients for anti-mycobacterial therapy-A pilot study.

Increasing evidence links a worldwide bacterial infection of cattle and other animal species by Mycobacterium avium ssp. paratuberculosis (MAP) to Crohn's disease (CD). A large, FDA phase 2/3 controlled clinical trial of combination antimycobacterial antibiotic therapy for CD has been completed, and the report describing the trial is pending publication. The identification of MAP infection in CD patients will become increasingly important. Thus, it is desirable to develop MAP-based tests that accurately predict which CD patients have a MAP infection. A prospective, case-control laboratory test study of 199 subjects (61 CD patients and 138 non-CD controls) was performed using a panel of MAP antigens, including Hsp65, PknG, PtpA, CL1, and MAP IDEXX, which were measured under blind conditions in the plasma of the 199 subjects. Results showed that compared to any individual MAP antigen, combinations of antigens showed improved CD classification performance. For the Hsp65 antigen, the sensitivity (SEN), specificity (SPE), positive predictive value (PPV), negative predictive value (NPV), correct classification (CC), and area under the curve (AUC) were 59.02%, 58.70%, 38.71%, 76.42%, 59.3% and 0.606, respectively. For the best combination of MAP antibodies (Hsp65 and PknG), the SEN, SPE, PPV, NPV, CC, and AUC were 59.02%, 60.87%, 40.00%, 77.06%, 60.30%, and 0.631, respectively. Further improvement of the CD classification performance was achieved by combining IFN-γ, IL-8, and IL-17 cytokines with antibodies against MAP antigens, yielding SEN, SPE, PPV, NPV, CC, and AUC of 62.3%, 62.32%, 42.22%, 78.9%, 62.31% and 0.708, respectively. Thus, combinations of antibodies against MAP antigens and cytokine levels yield better CD diagnostic predictive performance than any individual antibodies against MAP antigens.

Molecular Identification and Characterization of Piroplasms Infecting Cattle in Azad Kashmir

Molecular Identification and Characterization of Piroplasms Infecting Cattle in Azad Kashmir

Infectious bovine rhinotracheitis: Epidemiology, control, and impacts on livestock production and genetic resources

The present review aims to determine the epidemiology of infectious bovine rhinotracheitis (IBR), control measures, and its impact on livestock production and genetic resources. The literature search was conducted to select and compile peer-reviewed journals, book chapters, and international organization proceedings on the epidemiology, control, and impacts of IBR. IBR is a highly contagious disease of cattle that causes substantial economic losses throughout the world, particularly in the dairy and beef industries. Bovine alphaherpesvirus-1 causes this infectious viral disease, affecting the respiratory, and reproductive systems. IBR causes severe inflammation and dysfunction of the respiratory system. Infection of the reproductive system is responsible for abortion, retained placenta, metritis, and balanoposthitis. The transmission is by inhalation, contact with nasal and genital secretions, and fomites. Epidemiologically, the disease is known for its distinct latency characteristics. The infectious agent establishes a lifelong latent infection in the peripheral nervous system. The introduction of latently infected cattle, high stocking densities, confined pens, concurrent diseases, and low ambient temperatures increase the transmission and severity of the disease. The disease has no specific drug treatments, so control and prevention measures have inevitable roles. IBR is a significant constraint on livestock production globally, particularly in developing countries. It causes poor reproductive performance and productivity, the loss of replacement herds, and the culling of mature, productive animals. The implementation of strict biosecurity measures, immunization, quarantine, herd screening, and proper herd management are the most important control and prevention strategies.

First Molecular Evidence of Anaplasma marginale Infection in Naturally Infected Cattle in Myanmar with Severe Hemolytic Anemia

First Molecular Evidence of Anaplasma marginale Infection in Naturally Infected Cattle in Myanmar with Severe Hemolytic Anemia

Analysis of Coinfection Pathogens From Foot‐and‐Mouth Disease Virus Persistently Infected Cattle Using Oxford Nanopore Sequencing

The persistent infection caused by foot‐and‐mouth disease virus (FMDV) still lacks a reliable explanation, as its etiology and maintenance are intricate and potentially involve concurrent infections with multiple pathogens. In this study, we utilized the nanopore platform for direct sequencing of clinical samples obtained from cattle persistently infected with FMDV serotype O and investigated the distribution characteristics of coinfecting pathogens in their pharyngeal region. Briefly, we exploited Oxford Nanopore sequencing technology to generate high‐quality and sufficient sequence data for the comprehensive characterization of microbial genomes. Furthermore, we performed sequence comparison, alignment, and phylogenetic tree construction. Our findings revealed a total of 23 viruses in FMDV carrier bovine, with FMDV, bovine orthopneumovirus, and Choristoneura fumiferana granulovirus emerging as the top three identified pathogens. The analysis unexpectedly revealed the presence of porcine circovirus type 2 and pepper mild mottle virus among the viral genes detected in the bovine FMDV carrier. Compared to noncarrier, carrier bovine of FMDV exhibited a greater diversity and abundance of mycoplasma types as well as reads counts. Therefore, we propose that the establishment and perpetuation of persistent FMDV infection may be attributed to the simultaneous presence of other viral agents and mycoplasmas. These findings highlight the significance of investigating multipathogen coinfection in elucidating the etiology of persistent FMD virus infection.

Experimental infection of cattle, sheep, and goats with the newly emerged epizootic hemorrhagic disease virus serotype 8.

Epizootic hemorrhagic disease virus serotype 8 (EHDV-8) emerged in Europe for the first time in late 2022. In this study, we investigated the kinetics of EHDV-8 infection in cattle, sheep, and goats. Following experimental infection with EHDV-8, four out of five calves displayed fever, while another calf exhibited ulcerative and crusty lesions of the muzzle. RNAemia peaked at day 7 post infection in all calves and remained relatively stable till the end of the study, at 78 days post infection. Infectious virus was isolated up to 21 days post infection in one calf. As far as small ruminants are concerned, one sheep experienced fever and two out of five had consistent RNAemia that lasted until the end of the study. Remarkably, infectious virus was evidenced at day 7 post infection in one sheep. In goats, no RNA was observed. All infected animals seroconverted, and a neutralizing immune response was observed in all species, with calves exhibiting a more robust response than sheep and goats. Our study provides insights into the kinetics of EHDV-8 infection and the host immune responses. We also highlight that sheep may also play a role in EHDV-8 epidemiology. Altogether, the data gathered in this study could have important implications for disease control and prevention strategies, providing crucial information to policy makers to mitigate the impact of this viral disease on livestock.

Prevalence of Bovine Cysticercosis, Human Taeniasis and Associated Risk Factors in Selected Towns of Silte Zone

Bovine cysticercosis is an infection of cattle caused by the larval stage of Cysticercus Bovis, the human intestinal cestodes and it has economical and public health importance. Across-sectional study was conducted from March 2022 to August 2022 to determine the prevalence of Bovine Cysticercosis, Human Taeniasis and associated risk factors in selected towns of Silte zone. The study was conducted in Silte zone municipal abbatoir in cattle slaughtered at Kilto, Kutery, Kirate and Werabe town municipal abattoirs. Systematic random sampling technique was used to collect data from abattoir survey of the study animals and questionnaire survey collected data stored by using in Epi data software and analyzed using (SPSS-22) software program. The study animals were 422 cattle which were systematic randomly selected. The present study revealed that the overall prevalence of C.bovis was 36 %, which indicated a high prevalence of the parasite in the study area. A prevalence of 35.7%, 35.92%, 37.96% and 34.11% were Kilto, Kutery, Kirate and Werabe Tawon were observed, respectively. Among considered risk factors, sex, body condition and breed showed statistically significant difference in prevalence of C. bovis in study area. Regarding the anatomical distribution of the cysts, shoulder muscle showed highest prevalence 28.44%, was followed by tongue 20.79% tricepsbrachi muscle 18.35%, masseter muscle 17.74%, heart 12.84%, and liver 1.8%. Out of 110 respondents, 64.5% had contracted T.saginata. Among considered risk factors, sex, age , occupation, education status, raw meat consumption and knowledge about the disease, showed statistically significant difference in prevalence of T. saginata in study area. The findings of this study indicated that importance of Bovine Cysticercosis and Taeniasis in the study area. Therefore, attention should be given to the public awareness, detailed meat inspection to be safe to public health, consumption of well-cooked cattle meat should be implemented for breaking the cycle of the diseases and promote meat industry in the country.

SEROLOGICAL SCREENING FOR Neospora caninum INFECTION IN A DAIRY CATTLE FARM WITH REPRODUCTIVE DISORDERS, IN SOUTH-EASTERN ROMANIA

Neospora caninum is an apicomplexan protozoa parasite that causes reproductive disorders in cattle worldwide. Despite the high seroprevalence reported in Romania, there are limited data on N. caninum infection in dairy cattle, and no studies have evaluated the presence of infection over time in a limited area. Therefore, this study aimed to assess the seroprevalence of N. caninum in a dairy cattle farm in Southeastern Romania where a previously study reported about the cattle exposure to N. caninum infection. A total of 85 cattle, assigned in four groups, according to the reproductive status (repeated breeding syndrome, history of abortion, pregnant cows, and fresh cows) were tested for the presence of N. caninum antibodies, using an indirect ELISA test. The overall seroprevalence was 28.23% (95% CI: 18.67–37.80). According to the reproductive groups, the seroprevalence varied between 19.04% (95% CI: 2.25-35.84) in fresh cows to 38.09% (95% CI: 17.32 - 58.87) in cows with repeated breeding syndrome. By these findings new information is provided about the disease's presence in the studied farm, implying that infection with N. caninum may be the primary cause of reported reproductive disorders, as well as about the infection's persistent nature.

A Current Update on Neospora caninum

Neospora caninum is an apicomplexan protozoan parasite, which was first identified as a cause of canine paralysis. This parasite is now recognized as an important cause of reproductive problems and abortion in cows. Prior to its first recognition in Norwegian dogs in 1984 and consequential classification as a distinct species in 1988, many N. caninum infections were misdiagnosed as toxoplasmosis. Neospora has a complex life cycle and transmission routes. Carnivores probably become infected by ingesting tissue cysts containing bradyzoites, and herbivores probably become infected by the ingestion of food or drinking water contaminated by N. caninum sporulated oocysts from the feces of carnivores. During pregnancy it becomes activated again, breaks out of the tissue cysts and migrates to the placenta. Infection of the placenta may lead to abortion, which would provide a source of contaminated meat for definitive hosts. In addition, the parasite may be transmitted to the foetus, which can lead to the birth of congenitally and persistently infected calves. Most reports of neosporosis outbreaks have occurred in cows that are intensively managed; thus, the incidence increases as larger cattle farms with intensive feeding practices become more common. Immunofluorescent antibody test (IFAT) and indirect enzyme-linked immunosorbent assay (ELISA) and histopathology of fetus are used for diagnosis. At present, there is no effective treatment for bovine neosporosis. Control of abortion in infected cattle depends on saving food and water sources and the grazing environment from feces of carnivores, properly discarding aborted feoutus and control of dog.

Cattle Pinkeye Disease Classification using Machine Learning

Pinkeye (infectious bovine keratoconjunctivitis, or IBK) is a bacterial infection of the cattle eye that causes inflammation and, in severe cases, temporary or permanent blindness. It is a painful, debilitating condition that can severely affect animal productivity. Due to lower weight gain, lower milk production, and higher medical costs, the cattle industry could experience large losses. Previous studies tried to classify livestock diseases using machine learning, but there has been a lack of studies conducted on pinkeye disease classification. The proposed study aims to design a classification model to classify whether the infected cattle have pinkeye or not at an early stage by analyzing a set of attributes. The study collected data from the Wolaita Sodo Kenido Koyisha Wereda Livestock and Fishery Office. The significance of this study is to prevent the expansion of disease among the cattle with an early detection for taking precautionary measures. The researchers used the percentage splits 80/20, 70/30, 60/40, and 90/10 to build classification models. Based on the results of the experiments, the researcher chose the 70/30 split due to the better performance obtained. The study trained four different models, including Random Forest, AdaBoost, Artificial Neural Network, and Extreme Gradient Boost algorithms. These models are selected based on an exhaustive study conducted. To assess the algorithm's performance, confusion matrix, accuracy, precision, recall, and f1-score have all been utilized. By a 99.15% accuracy, the Artificial Neural Network outperforms the other algorithms by all the metrics except recall.
 Keywords: Machine learning, Infectious bovine keratoconjunctivitis, IBK, Cattle pinkeye, Pinkeye disease classification

BUPARVAQUONE

Theileriosis is a type of blood protozoan infection caused by the transmission of Theileria spp. species in tropical and subtropical regions by ticks belonging to the Ixodidae family. The disease progresses with high mortality and morbidity especially in ruminants. While deaths are observed in the first few days in peracute cases, it is reported that deaths are observed within the first weeks in acute cases. Fever, lymphadenopathy, respiratory distress, increase in heart rate, decrease in milk yield, weight loss, abortion and death are observed in patients. Buparvaquone, an antiprotozoal drug of the hydroxynaphthoquinone group, is the single most effective drug used in the treatment of the disease. Although it is recommended to use 2.5 mg/kg intramuscularly against theileriosis infection in cattle, it can be used in the same dosage regimen 2-3 days later if deemed necessary by the physician. In case of use of the drug, local reactions may develop in the area where it is applied, and it is not recommended to be used with vaccines and in pregnant animals. The drug is generally considered safe. Since the disease is transmitted by ticks, it is recommended to add an ectoparasitic agent to the treatment protocol. In this review, it has been tried to give information about the use of buparvaquone in the treatment of theileriosis.

Geographic expansion of Fasciola hepatica (Linnaeus, 1758) due to changes in land use and cover in Brazil

Fasciolosis is caused by parasites of the genus Fasciola, affecting animals and humans worldwide. In South America, the disease is a result of infection with Fasciola hepatica and although animal infections are more frequently reported, the full extent of the impact on human health due to underdiagnosis remains uncertain. This study analyzed changes in land use and the distribution of F. hepatica in bovine livers in Brazil over 18 years. Data on land use and land cover were collected from the Mapbiomas Project. Data on 414,481,963 slaughtered cattle and condemned livers due to F. hepatica infection were obtained from 4,433 municipalities. Joinpoint analysis was used to study the time series, and the Susceptible-Infected-Recovered (SIR) model was utilized to explore the behavior of F. hepatica infection. In the North, pasture areas significantly increased (P = 0.000001), while forested areas decreased (P = 0.000001). The midwestern and northern regions concentrated the highest number (>290 million) of cattle slaughtered in Brazil. More than 2 million bovine livers were infected by F. hepatica. The infected cattle originated from 194 municipalities in 2002, increasing to 747 in 2020. We consider that the changes in land use and intense cattle transportation may have caused the expansion of F. hepatica. The SIR model analyzed the spread of the disease looking at all six biomes: Caatinga, Amazon Forest, Cerrado, Pantanal, Atlantic Forest, and Pampa. Moreover, this infection not only threatens the health of animals but is also a major concern to biodiversity and vulnerable human communities in South America. Emblematic biomes such as the Amazon basin already face challenges with logging, desertification, and loss of biodiversity. Therefore, strategies for mitigating infection should include controlling illegal pasture areas, establishing health inspections of animal transport, quarantine of newly arrived animals, and livestock zoning, as well as clear One Health policies.

Detection and quantification of Babesia bovis and Babesia bigemina using different target genes

Molecular assays have been widely used for the detection and quantification of bovine babesiosis due to their high sensitivity and specificity. However, variations in the sensitivity of pathogen detection may occur depending on the selected target gene. Thus, this study aimed to compare the detection sensitivity (DS) of Babesia bovis and B. bigemina infection levels in artificially and naturally infected cattle using quantitative PCR (qPCR) and six target genes. For B. bovis, the merozoite surface antigen genes 2b and 2c (msa-2b and msa-2c), and the mitochondrial cytochrome b gene (cybmt) were used. For B. bigemina, the genes encoding the proteins associated with rhoptry 1c (rap-1c), rap-1a, and cybmt were used. Six bovines, free of babesiosis, were artificially infected with 1 × 10−8 red blood cells infected (iRBC) with B. bovis (n = 3) or 1 × 10−6B. bigemina iRBC (n = 3). The animals were evaluated daily until parasitemia was confirmed (≥ 2.0%). The quantity of iRBC present in each animal was determined by examining blood smears. Blood samples were then subjected to DNA extraction, serial dilution, and qPCR analysis to determine the DS of each target gene. In addition, 30 calves naturally infected by Babesia spp. were also evaluated using the same six target genes. Regarding the artificial infection, B. bovis cybmt showed 25-fold higher sensitivity than the msa-2b and msa-2c genes, while the B. bigemina cybmt exhibited 5-fold and 25-fold higher sensitivity than the rap-1a and rap-1c genes, respectively. The rap-1a gene was found to be 5 times more sensitive than the rap-1c gene, while the B. bovis msa-2b and msa-2c genes exhibited similar DS. The positive frequencies of naturally infected calves for the target cybmt, msa-2b, and msa-2c genes (B. bovis) were: 100%, 33.3% and 50%, while cybmt, rap-1a, and rap-1c genes (B. bigemina) were 90%, 83.3%, and 63.3%, respectively. This study may contribute to the selection of suitable genes for molecular monitoring of bovine babesiosis. Mitochondrial genes could be considered as an alternative to improve the sensitivity of B. bovis and B. bigemina detection using qPCR.

Study of the spread of minor viral cattle infections (Leukemia, Immunodeficiency, and Spumavirus infection) using polymerase chain reaction

The aim of the study was to investigate the prevalence of minor cattle infections (leukemia, bovine immunodeficiency and spumavirus infection) using the polymerase chain reaction (PCR). Blood samples were collected from cows in conditionally leukemia-free farms in ten regions of Ukraine to determine the presence of these infections. The samples were examined via classical PCR to detect the genetic material of the specific fragment of the ENV gene of the leukemia virus using BLV-env-3/BLV-env-4 primers recommended by the OIE. To identify the proviral DNA of bovine foamy virus (BFV), primers Int 1-Int 2 and Int 3-Int 4 were used, and for the detection of bovine immunodeficiency virus (BIV) proviral DNA, a pair of primers RT_+(–) flanking the conservative domain of reverse transcriptase and a pair of primers flanking the pol gene of the BIV were selected. The situation concerning leukemia is most severe in Sumy and Kharkiv regions. A significant percentage of animals carrying the foamy virus was observed in farms in Kirovohrad, Kherson, Donetsk, and Kharkiv regions. Moreover, genetic material of the immunodeficiency virus was found in samples from Kirovohrad, Donetsk, and Kherson regions. These results indicate a significant prevalence of minor infections among cattle in Ukraine due to a lack of awareness among livestock workers, highlighting the necessity for comprehensive sanitary and preventive measures

The Fasciola hepatica egg development and hatching test (EDHT) using commercial drugs: a simple protocol for tackling anthelminthic resistance and promoting cattle productivity.

Fasciolosis is an important zoonotic disease caused by the trematode Fasciola hepatica, and it causes great losses in bovine production. The anthelmintic resistance is a major problem in the control of fasciolosis. In this study, the F. hepatica egg development and hatching test (EDHT) was used for the evaluation of the ovicidal activity of commercial drugs, commonly used for treating infected cattle, which reflects F. hepatica anthelminthic resistance in infected bovines, according to recent literature. Bile samples from F. hepatica naturally parasitized cattle were obtained from slaughterhouses in the cities of Lages and Otacílio Costa, Santa Catarina State, Brazil. The bile was washed, the eggs were recovered, quantified, and distributed in universal collectors, with a minimum of 1,000 eggs per vial. Four commercial drugs were used in this study, containing albendazole sulfoxide (ABDZ), closantel (CSTL), nitroxynil (NTXL), and triclabendazole with fenbendazole (TBZF). The drugs were diluted according to the manufacturer instructions. All drugs, and the respective control, were tested in triplicates, with the quantity of recovered eggs determining the number of drugs to be tested. The vials were incubated for 28days at 27°C, and the eggs were classified according to their degree of development under a stereomicroscope. In total, 121 egg samples were analyzed. Two samples were identified as resistant to TBZF. Undetermined resistance/susceptibility has been found in two isolates treated with ABDZ, one treated with NTXL and six treated with TBZF. CSTL did not present ovicidal activity and cannot be used in EDHT. This is the first time that commercial drugs were used in F. hepatica EDHT.

Characterization of Rosculus vilicus sp. nov., a rhizarian amoeba interacting with Mycobacterium avium subsp. paratuberculosis.

Free-living amoebae are described as potential reservoirs for pathogenic bacteria in the environment. It has been hypothesized that this might be the case for Mycobacterium avium subsp. paratuberculosis, the bacterium responsible for paratuberculosis. In a previous work, we isolated an amoeba from a water sample in the environment of infected cattle and showed that this amoeba was associated with Mycobacterium avium subsp. paratuberculosis. While a partial 18S rRNA gene has allowed us to suggest that this amoeba was Rosculus-like, at that time we were not able to sub-cultivate it. In the present study, we succeeded in cultivating this strain at 20-25°C. This amoeba is among the smallest (5-7 μm) described. The sequencing of the whole genome allowed us to extract the full 18S rRNA gene and propose this strain as a new species of the Rosculus genus, i.e., R. vilicus. Of note, the mitochondrial genome is particularly large (184,954 bp). Finally, we showed that this amoeba was able to phagocyte Mycobacterium avium subsp. paratuberculosis and that the bacterium was still observed within amoebae after at least 3 days. In conclusion, we characterized a new environmental amoeba species at the cellular and genome level that was able to interact with Mycobacterium avium subsp. paratuberculosis. As a result, R. vilicus is a potential candidate as environmental reservoir for Mycobacterium avium subsp. paratuberculosis but further experiments are needed to test this hypothesis.

Seroepidemiological investigation of Getah virus in the China-Myanmar border area from 2022-2023.

Getah Virus (GETV) is an RNA virus that is transmitted by mosquitoes and can cause disease or death in a variety of vertebrates. Its prevalence is increasingly severe in Asia. This study conducted a GETV epidemiological investigation on 1,300 bovine sera collected in the Honghe Prefecture of Yunnan Province on the China-Myanmar border from 2022 to 2023. The positive rate of GETV antibodies in bovine serum in Honghe Prefecture was determined to be 20.25% through indirect Enzyme-linked immunosorbent test (ELISA) methods. Using Real-time PCR methods to detect GETV RNA in bovine serum, the positive rate was 0.23% (3/1300), and viral nucleic acids were only detected in three bovine sera in Jianshui area in 2022. The YN2305 strain was successfully isolated from mouse neuroblastoma (N2a) cells and the complete gene sequence was obtained. All the above results indicate the existence of GETV infection in cattle in Honghe Prefecture, Yunnan Province. Homology and genetic evolution analysis found that the isolated strain has a high homology with the JL1808 strain isolated from cattle in 2018, with a nucleotide identity of 100%, and a nucleotide identity of 99.8% with the SD17-09 strain isolated from foxes in 2017. Compared with the nucleotides of 44 virus strains published in Genbank, YN2305 has multiple nucleotide site mutations in the structural gene E2 and non-structural gene NS. The nucleotide and amino acid identity of the E2 gene are 94.2-100% and 96.4-100%, respectively. Genetic evolution analysis found that this virus strain is most closely related to the bovine origin JL1808, and it is in gene group III with HuN1, Kochi-01, SD17-09, MI-110-C1, and MI-110-C2 strains that causes significant clinical symptoms in Chinese pig, fox and horse populations, belonging to the same evolutionary branch. This study determined the infection rate, genotype, and main prevalence areas of GETV in bovine sera in the China-Myanmar border area. Therefore, the epidemiological investigation of GETV infection in multiple animal hosts should be further expanded, and research on its pathogenicity and vectors should be carried out.

Characterization of Three New Outer Membrane Adhesion Proteins in Fusobacterium necrophorum.

Fusobacterium necrophorum, an anaerobic Gram-negative pathogen, causes necrotic cattle infections, impacting livestock health and the US feedlot industry. Antibiotic administration is the mainstay for treating F. necrophorum infections, although resistance hampers their effectiveness. Vaccination, especially targeting outer membrane proteins (OMPs) due to their antigenic properties and host specificity, offers an alternative to antibiotics. This study identified high-binding-affinity adhesion proteins from F. necrophorum using binding and pull-down assays with bovine adrenal gland endothelial cells (EJG). Four OMP candidates (17.5 kDa/OmpH, 22.7 kDa/OmpA, 66.3 kDa/cell surface protein (CSP), and a previously characterized 43 kDa OMP) were expressed as recombinant proteins and purified. Rabbit polyclonal antibodies to recombinant OMPs were generated, and their ability to inhibit bacterial binding in vitro was assessed. The results show that treatment with individual polyclonal antibodies against 43 kDa significantly inhibited bacterial adhesion, while other antibodies were less potent. However, combinations of two or more antibodies showed a more prominent inhibitory effect on host-cell adhesion. Thus, our findings suggest that the identified OMPs are involved in fusobacterial attachment to host cells and may have the potential to be leveraged in combination for vaccine development. Future in vivo studies are needed to validate their roles and test the feasibility of an OMP-based subunit vaccine against fusobacterial infections.

The effectiveness of scientifically based monitoring programs and therapeutic and preventive measures for controlled infectious diseases of animals

The aim of the work was to assess the effectiveness of an improved monitoring program for controlled infectious animal diseases and individual vaccination programs for acute respiratory viral infection in cattle. To fulfill the tasks set, serological studies, PCR diagnostics, bacteriological and coprological methods of examining biological samples from animals were carried out. As a result of the work, the main factors influencing the effectiveness of vaccine prophylaxis of acute respiratory viral infection in cattle populations have been identified. It was found that in three administrative and administrative districts of the Sverdlovsk region, the main factors in 35.1% of cases are violations of the rules of vaccination of acute respiratory viral infection of cattle, in 13.5% of cases - violations of zoo-hygienic and veterinary–sanitary conditions of keeping farm animals. A comprehensive assessment of the effectiveness of individual vaccination programs for cattle against acute respiratory viral infection has been carried out, taking into account the epizootological situation in agricultural organizations. It was shown that vaccination of cattle against acute respiratory viral infection according to individual programs ensured the formation of specific immunity in 92.5-95.0% of animals. The number of immunotolerant individuals and animals with a low level of immunoreactivity in the physiological group of young cattle did not exceed 3.5%, in the physiological group of adult animals – 1.25%. The high efficiency of improved scientifically based programs for monitoring, diagnosis, therapeutic, preventive and health measures to protect animals from epizootically significant infectious diseases of cattle among the populations of farm animals of the Ural Federal District has been confirmed.

Detection of bovine coronavirus (BCoV) infection in cattle with clinical respiratory signs by PCR and investigation of the serological status of these animals

Aim: It was aimed to reveal the antigenic and serological prevalence of bovine coronavirus (BCoV) in cattle with clinically respiratory infection and to evaluate the relationship between virus shedding and serological status of animals in this study. Materials and Methods: In the study, nasal swab samples were collected from a total of 92 cattle of different gender between 0 and 2 years of age with clinical respiratory symptoms. These samples were subjected to RT-PCR using specific primer pairs. Furthermore, serum samples were also collected from the same animals and evaluated for BCoV-specific antibodies through an indirect ELISA method. Results: Ten (10.87%) swap samples were defined as positive for BCoV using RT-PCR. The seropositivity rate was 93.48% (86/92) in cattle by ELISA and 90% (9/10) in virus-shedding animals with nasal swab samples. Conclusion: The fact that 93.47% seropositivity was detected in unvaccinated animals against coronavirus in this study indicates that the animals were exposed to BCoV through colostrum or at a certain period of their lives. However the fact that 9 out of 10 animals with BCoV detected in swab samples also have BCoV-specific antibodies casts doubt on the efficacy of these antibodies in protecting against respiratory BCoV infections. We concluded that more detailed studies are needed to reveal the role of antibodies in respiratory coronavirus infections.