Carrier Animals Research Articles

Mixed Leptospira infections in domestic animals from a rural community with high leptospirosis endemicity.

Leptospirosis is one of the most common zoonoses in the world which is associated with a severe febrile disease in humans causing a variety of syndromes including meningitis, interstitial nephritis, hepatitis, and sometimes death. Leptospirosis is caused by different pathogenic Leptospira species divided into almost 30 serogroups and more than 300 serovars which are carried by some animal asymptomatic chronic infections. Humans can become infected through direct contact with animal urine or indirectly by coming into contact with fresh water or mud contaminated with urine. In this research, we looked for leptospiral DNA in urine samples from dogs living in a rural, low-income and highly endemic community in the coast of Ecuador. We used molecular biology and next-generation sequencing for the detection. Our results showed evidence of two Leptospira species, L interrogans and L. santarosai, genomes in three dogs. It has been widely known that animal carriers are typically infected with a single leptospiral strain. However, recent reports, including the present one, indicate that carrier animals may be coinfected with two or more leptospiral species.

A Splice Site Variant in ADAMTS3 Is the Likely Causal Variant for Pulmonary Hypoplasia with Anasarca in Persian/Persian-Cross Sheep.

Pulmonary hypoplasia with anasarca, or hydrops fetalis, is characterized by stillbirth, diffuse oedema, and generalized lymph node hypoplasia. The enlarged fetus frequently causes dystocia. The disease has been reported in cattle and sheep as an inherited condition with a recessive mode of inheritance. This is the first report of the disease in Persian/Persian-cross sheep in Australia. Affected fetuses were reported from three flocks, and a total of eleven affected, eleven obligate carrier, and 188 related Persian/Persian-cross animals were available for analysis, as well as unrelated control animals. SNP genotyping revealed a region of homozygosity in affected animals on ovine chromosome six, which contained the functional candidate gene ADAMTS3. Whole genome sequencing of two affected fetuses and one obligate carrier ewe revealed a single nucleotide deletion, ENSOARG00000013204:g.87124344delC, located 3 bp downstream from a donor splice site region in the ADAMTS3 gene. Sanger sequencing of cDNA containing this variant further revealed that it is likely to introduce an early splice site in exon 14, resulting in a loss of 6 amino acids at the junction of exon 14 and intron 14/15. A genotyping assay was developed, and the ENSOARG00000013204:g.87124344delC segregated with disease in 209 animals, allowing for effective identification of carrier animals.

Molecular detection and association of 12.1kb deletion within the high mobility AT-hook 2 gene in the Netherlands dwarf rabbit (Oryctolagus Cuniculus).

Rabbits are mainly bred for human consumption and medical research. However, it has been recently showed that several rabbit breeds are also kept as pets for human leisure. The Netherlands dwarf rabbit is currently in the immense interest of many Vietnamese customers due to its personality and miniature stature. However, 12.1kb deletion from position 44,709,089 to 44,721,236bp in the high mobility AT-hook 2 (HMGA2) gene on chromosome 4 was identified as the structural variant causing dwarfism and altered craniofacial development in this breed. It has been documented that HMGA2 plays an important role in regulating growth and individuals with genotype HMGA2 del/del are fatal several days after birth. Despite the economically high value of the Netherlands dwarf rabbit, there has been no study on the genetic survey of lethal alleles in this breed in Vietnam. The aim of this study is to develop a fast and reliable method to screen the frequency of lethal alleles of HMGA2 in the South of Vietnam. Rabbit saliva was collected, and DNA extraction was followed. Multiplex polymerase chain reaction (PCR) with three primers was optimized and performed to detect the presence of 12.1kb deletion within the HMGA2 sequence. Our data showed that the 12.1kb deletion in the Netherlands dwarf rabbit population was detected by our optimized multiplex PCR. In 100 rabbit animals, 34 and 16 individuals were homozygous wild type (+/+) and homozygous mutant (del/del), respectively, while 50 rabbits were heterozygous. The frequency of HMGA2 lethal allele carrier was 66% (66/100 individuals). Our results indicated that we successfully developed a fast, accurate multiplex PCR to detect carrier individuals. Verification of the genotypes was followed by sequencing. We recommend implementing our multiplex PCR procedure in genetic selection for carrier and homozygous wild-type animals in the mating scheme to prevent the lethality of the rabbit offspring. Additionally, awareness should be raised among rabbit breeders to monitor the genetic makeup of the Netherlands dwarf rabbit populations. However, due to the limitation of the sample size, more samples should be taken in future studies to obtain the genetic frequency of the HMGA2 lethal allele more accurately.

One Health and sex and gender-related perspective in the ecosystem: Interactions among drivers involved in the risk of leptospirosis in Europe. A scoping review

Leptospirosis has a complex transmission, involving rodents and many species of domestic and wild animals. Carrier animals spread leptospires, contaminating soil and water, the main sources of human infection. The risk of infection is modulated by socio-economic factors, environment and host animals and has changed, historically linked to agriculture but now prevalent in recreational environments. Leptospirosis also reveal gender-specific exposure patterns that determine infection risks. Emphasizing the interconnectedness of humans, animals, and the environment, the One Health approach highlights the ecosystem dynamics through which leptospires interact with hosts and abiotic factors, ensuring their survival and transmission.We advocate for integrating gender considerations into the ecosystem dynamics of complex zoonoses, such as leptospirosis, through a One Health perspective. This approach, yet to be fully explored, may enhance our understanding of the infection and its modulating factors. A scoping review of the literature was conducted across Embase and Pubmed databases to collect information on sex and gender-specific drivers, sources of infections, environmental drivers, and related risks of leptospirosis. Quantitative data were extracted from the articles selected according to a list of criteria, and analyzed to discern sex and gender disparities and identify primary drivers of leptospirosis. We confirmed that the excess of male leptospirosis cases described in many parts of the world is also present in Europe. Furthermore, we identified environmental and sociocultural drivers and hypothesized their interactions between and within human, animal, and environmental sectors. These interactions modulate direct and indirect exposure to Leptospira, heightening infection risks across the ecosystem. Based on our findings, utilizing leptospirosis as a model, we advocate for integrating One Health and gender approaches in public health practices to better plan and implement more effective and timely intervention measures.

Distribution trends of bovine Anaplasma marginale in Iowa, based upon veterinary diagnostic lab submissions from 2017-2022

Anaplasma marginale is the common etiological agent of bovine anaplasmosis. Infection results in erythrocyte de­struction leading to the clinical signs of anemia, hypoxia, abortion, jaundice and sudden death. Cattle that survive this acute phase or have lower levels of initial bacteremia become chronic, persistent carriers. Carrier animals serve as reser­voirs for the organism and allow infection to spread via me­chanical or biological vectors, to susceptible herdmates. The objective of this study was to report the distribution trends of A. marginale positive test results during a 5-year period in Iowa. This study evaluated Iowa State University Veterinary Diagnostic Lab (ISU VDL) testing results from bovine cases submitted from January 1, 2017 to January 1, 2022, for molecu­lar and serological detection of all stages of anaplasmosis. Cattle residing in Iowa with positive results for PCR or com­petitive ELISA were included in the analysis. The state was divided into 4 geographical districts (1 = northeast, 2 = south­east, 3 = southwest, and 4 = northwest) and the number of pos­itive tests in each district was determined. Total positive tests by district included: northeast 282; southeast 277; southwest 223; northwest 281. Disease spatial analysis mapping, based upon geographic longitude and latitude location of herds with positive diagnostic tests, illustrate progressive disease expan­sion from the southern counties of Iowa, near the Missouri border, into the northern parts of Iowa. These results suggest that A. marginale has developed a widespread distribution across the state of Iowa.

Comparison of Salmonella Dublin SRP vaccination programs on the development of immunity in calves

Salmonella Dublin is a common cause of calf illness and is en­demic in many regions of the U.S. dairy industry. A 2016 report from the National Veterinary Services Lab found S. Dublin was the most commonly isolated Salmonella serotype obtained from ill cattle in the U.S. This serotype is also considered to be host-adapted in bovine and therefore carrier animals that appear normal can be shedders and a source for maintaining the infec­tion within a herd. As such, finding mechanisms to protect naïve animals from clinical disease can reduce losses in dairy herds. The objective of this work was to describe the immune response stimulated by experimental Salmonella Dublin SRP vaccines.

Bloodborne pathogens in beef herds – a Kansas practitioner’s perspective

Management options for bloodborne diseases depend on preva­lence (herd level and geographic), disease stage and production class. Opportunities to manage disease can be classified ac­cording to disease stage. Newer studies show that, in contrast to older studies, there is not currently a known legal way to clear animals of anaplasmosis. The only currently labeled products for treatment of acute clinical anaplasmosis are injectable oxy­tetracyclines. For a time, an enrofloxacin product (Baytril-CA) was marketed with a label for treatment of anaplasmosis, but the conditional approval application has been withdrawn. Op­portunities for leukosis management are limited to exposure control as there are no effective treatments for animals in the clinical stage and no effective methods to clear infected non-clinical animals. Due to the relatively high prevalence in beef herds, a strict test-and-cull strategy is not practical. Instead identifying animals with high pre-viral load who are most infectious provides an option to decrease disease levels with reasonable economics at the farm level. More research is neces­sary to fully quantify production effects for carrier animals of both bovine leukosis and anaplasmosis.

Diagnostic performance of a rapid immunochromatographic test for the simultaneous detection of antibodies to Theileria equi and Babesia caballi in horses and donkeys

BackgroundEquine piroplasmosis is caused by two tick-borne protozoan parasites, Theileria equi and Babesia caballi,, which are clinically relevant in susceptible horses, donkeys, and mules. Moreover, equine piroplasmosis significantly constrains international trading and equestrian events. Rapidly diagnosing both parasites in carrier animals is essential for implementing effective control measures. Here, a rapid immunochromatographic test for the simultaneous detection of antibodies to T. equi and B. caballi was evaluated using samples from horses and donkeys collected in Greece, Israel, and Italy. The results were compared with an improved competitive enzyme-linked immunosorbent assay (cELISA) for detecting antibodies to both parasites using the same panel of samples.MethodsBlood samples were collected from 255 horses and donkeys. The panel consisted of 129 horses sampled at four locations in northern Greece, 105 donkeys sampled at four locations in Sicily, and 21 horses sampled at two locations in Israel. The rapid test and the cELISA were performed according to the manufacturer’s instructions, and the results were subjected to a statistical analysis to determine the sensitivity and specificity of both tests and their association.ResultsThe immunochromatographic test provided a result within 15 min and can be performed in the field, detecting both pathogens simultaneously. The overall coincidence rate between the rapid test and the cELISA for detecting antibodies against T. equi was 93% and 92.9% for B. caballi. The rapid test’s sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for T. equi were above 91.5%. Sixteen samples were positive for both parasites in the rapid test and eight in the cELISA. Either test had no significant association between T. equi and B. caballi detection. The detection rates of both parasites were significantly higher in Italy than in Greece or Israel and in donkeys than in horses. The agreement for T. equi between the results of both tests was high in Greece (93.8%) and Italy (95.2%) and moderate in Israel (76.2%). For B. caballi, the specificity and NPV of the rapid test were high (94.2% and 98.3%, respectively), although the sensitivity and PPV were moderate (69.2% and 39.1%, respectively) due to the small sample size. However, for B. caballi, the sensitivity was higher with the rapid test.ConclusionsThe rapid test detected T. equi and B. caballi simultaneously in the field, potentially replacing laborious cELISA testing and is recommended for import/export purposes. The test can also be helpful for the differential diagnosis of clinical cases, since seropositivity may rule out equine piroplasmosis since it does not indicate current or active infection.Graphical

Evaluation of specific chicken IgY antibody value developing diagnostic capture antibody ELISA kit against Foot and Mouth disease.

The most preferred method for the detection of foot-and-mouth disease (FMD) viral antigen and identification of viral serotype is the enzyme-linked immunosorbent assay (ELISA). Diagnostic tests with high sensitivity are necessary both to distinguish infected vaccinated animals and execute disease control programs for the identification of the carrier animals. The current strategies for the detection of FMD virus are mainly based on the capture antibody (sandwich) ELISA test. The usage of laying pullets as an animal bioreactor for the production of specific egg yolk antibodies (IgY) has increased in recent years due to its high yield, affinity, low price, and quick production turnover. The present study aimed to produce a concentrated and purified IgY polyclonal antibody to design a capture antibody ELISA kit against the FMD virus (FMDV) serotype A. At first, laying hens were immunized with inactivated FMDV serotype virus, and then, on days 14, 21, and 28 following vaccination, the eggs and sera were collected. Afterward, the IgY polyclonal antibodies were extracted and purified from the chicken egg yolk using a polyethylene glycol 6000-ethanol precipitation procedure. Extracts were filtered, purified by ion exchange chromatography, and dialyzed. The purified IgY concentration, estimated by Bradford assay, confirmed its presence by SDS-PAGE and Western blot and also its specific immune reaction by Ouchterlony double immunodiffusion and Dot blot tests. Moreover, for achieving the optimum concentration of antigen/antibody (sera) in sandwich ELISA, a checkerboardtitrationtest was set up based on indirect ELISA results. Eventually, 119 previously confirmed samples (including 80 positive and 39 negative) by both real-time polymerase chain reaction (quantitative PCR, qPCR) and a commercial ELISA kit were used for evaluation of the sensitivity and accuracy of our developed Capture antibody ELISA kit. In this manner, the sensitivity and specificity of our designed kit were 100% and 98%, respectively. Accordingly, the present developed capture ELISA kit based on IgY had high sensitivity and specificity for FMD virus detection and it could be used in the future for both commercial detecting and serotyping applications.

The Influence of Environmental Sanitation on Stunting

Introduction: According to Pekanbaru City Health Department in 2019, there were 17.,67% of toddlers in Pekanbaru with poor nutritional status. Poor sanitation can trigger the emergence of infectious diseases that can reduce nutritional absorption in toddlers throughout the digestive process, resulting in stunting. The aim of this study was to analyze environmental sanitation influences on stunting. Methods: This research used case control study design. The case and control groups each received 30 samples. Independent variables include water source for sanitation, condition of latrines, condition of hand washing facilities with soap, condition of waste water drainage channels, management of household waste, type and condition of floors, presence of vectors and disease carrier animals, drinking water quality from biological conditions. The dependent variable was stunting. All data were collected using questionnaires that were asked directly to participants. Data analysis was performed by using the chi-square and multiple logistic regression tests. Results and Discussion: Water sources for sanitation, availability and condition of latrines, drinking water quality from biological terms influences on stunting (p-value <0.,05). Multivariate tests show that, the drinking water quality from biological terms and water sources for sanitation had a probability value of 21% to cause stunting. Conclusion: The dominant factor influences on stunting is the drinking water quality in biological terms and water sources for sanitation.

MOLECULAR GENETIC STATUS OF PIGS OF UKRAINIAN BREEDS SUITABLE FOR USE IN XENOTRANPLANTATION

Thousands of people in Ukraine and the world need organ transplants. However, the main obstacle to the wider use of transplantation remains the shortage of donor organs and tissues. To prevent human infection with viruses during organ transplantation, pigs are carefully screened for PERV retroviruses and animals with low expression levels of PERV-A and PERV-C are selected. The article is devoted to the discussion of the results of research on the frequency of retrovirus PERV types A and C in populations of Ukrainian pig breeds. The research was carried out on samples of pigs of the following breeds: Mirgorod, Great White, Poltava meat, Ukrainian meat, Ukrainian Steppe Ryaba, Landras, Pietren, Vietnamese Vyslobryukha, Vietnamese Meishan, and wild pig. Biomaterial samples (venous blood, bristles with hair bulbs) were collected for molecular genetic analysis. Isolation of genomic DNA from the samples was carried out by the salt method and using the Chelex-100 ion exchange resin. Genotyping was performed by the method of allele-specific (PCR-SSP) multiplex polymerase chain reaction using primers complementary to regions of the PERV-C, PERV-A gene loci. A fragment of the domestic pig alpha-actin locus (α-Actin) was used as an internal PCR control. Amplification was carried out in a thermal cycler "Tertsik-2" ("DNA-technology", RF). Electrophoretic separation of amplified DNA sections in multiplex PCR format was performed in a 2% agarose gel in a tris-borate electrophoresis buffer. It was established that among the studied groups of pigs, the highest concentration of retrovirus PEVR-C was found in animals of the breeds Vietnamese Vyslobrukha (100%), Poltava meat (75%), Ukrainian steppe spotted (55%), large white (50%), landrace (50%). The largest share of PEVR-A retrovirus carrier animals is characterized by the breeds of Vietnamese Vyslobrukha (100%), Poltava meat 95%), Pietren (80%) and Ukrainian meat (73%). The largest number of individuals free from PERV-A and PERV-C retroviruses were found in experimental groups of breeds of Ukrainian steppe spotted (75 and 45%, respectively), Myrhorod (32 and 75%, respectively), landrace (75 and 50%, respectively) and wild pig. Pigs these breeds can become promising organ donors for xenotransplantation.

Investigation of Some Autosomal Recessive Inherited Diseases (BLAD, DUMPS, CVM, and FXID) in Holstein Cattle

Genetic disorders are often transmitted via autosomal recessive inheritance, which negatively affect health, welfare, and yield traits in farm animals such as cattle. In this study, a total of 80 animals belonging to Holstein Friesian (HF) reared in the dairy farm of Akdeniz University were investigated in terms of Bovine Leukocyte Adhesion Deficieny (BLAD), Deficiency of Uridine Monophosphate Synthase (DUMPS), Factor XI Deficiency (FXID), and Complex Vertebral Malformation (CVM) via three molecular genotyping methods such as Polymerase Chain Reaction (PCR), PCR-Restriction Fragment Length Polymorphism (PCR-RFLP), and Allele-Sprcific PCR (AS-PCR). BLAD and DUMPS were analysed by PCR-RFLP, while PCR and AS-PCR were utilized to investigate FXID and CVM disorders, respectively. Based on fragment patterns on agarose gel electrophoresis, animals were genotyped as normal, mutant, and carrier. In this study, no carrier or mutant animals were detected for BLAD, CVM, DUMPS, and FXID diseases in HF cattle, since these animals were previously imported from disease-free dairy farms located in different provinces of Türkiye. Nevertheless, this population should be periodically checked for autosomal genetic disorders, since inherited diseases may be observed in the next generations due to causative mutations in the related genomic regions.

Role of genetic introgression in introducing mutant alleles in Bos indicus cattle and prevalence of lethal genetic disorders in Bos taurus × Bos indicus and Bos indicus cattle in India.

Fertility is an important trait associated with reproductive performance and animal welfare concern. Lethal alleles affect fertility through early embryonic death, abortions, and stillbirth depending on the genetic expression of the allele. Holstein Friesian and Jersey are two major Bos taurus breeds used widely for increasing milk yield along with purebreds of Bos indicus breeds like Gir, Kankrej, Sahiwal, and Tharparkar. In the present study, prevalence of lethal mutants in crossbred Holstein Friesian (CBHF, n = 2435), crossbred Jersey (CBJY, n = 2874), Gir (n = 3288), Kankrej (n = 593), Sahiwal (n = 965), and Tharparkar (n = 18) were studied. Heterozygous carrier animals were identified for bovine leukocyte adhesion deficiency (BLAD), Citrullinemia, complex vertebral malformation (CVM), Brachyspina, Holstein Haplotype 1 (HH1), Holstein Haplotype 3 (HH3),Holstein Haplotype 4 (HH4) and Jersey Haplotype 1 (JH1). Breed purity analysis confirmed inheritance of Bos taurus genes contributing to the presence of lethal mutant alleles like BLAD, Citrullinemia, HH1, and JH1 in apparently phenotypic Bos indicus animals. Screening and elimination of heterozygous carrier bulls/cows is essential to control fertility loss associated with lethal alleles.

Multi-antigen pan-sarbecovirus DNA vaccines generate protective T cell immune responses.

SARS-CoV-2 is the third zoonotic coronavirus to cause a major outbreak in humans in recent years, and many more SARS-like coronaviruses with pandemic potential are circulating in several animal species. Vaccines inducing T cell immunity against broadly conserved viral antigens may protect against hospitalisation and death caused by outbreaks such viruses. We report the design and pre-clinical testing of two T-cell-based pan-sarbecovirus vaccines, based on conserved regions within viral proteins of sarbecovirus isolates of human and other carrier animals, like bats and pangolins. One vaccine (CoVAX_ORF1ab) encoded antigens derived from non-structural proteins, the other (CoVAX_MNS) antigens from structural proteins. Both multi-antigen DNA vaccines contained a large set of antigens shared across sarbecoviruses and were rich in predicted and experimentally validated human T cell epitopes. In mice, the multi-antigen vaccines generated both CD8 and CD4 T cell responses to shared epitopes. Upon encounter of full-length spike antigen, CoVAX_MNS-induced CD4 T cells were responsible for accelerated CD8 T cell and IgG antibody responses specific to the incoming spike, irrespective of its sarbecovirus origin. Finally, both vaccines elicited partial protection against a lethal SARS-CoV-2 challenge in human-ACE2-transgenic mice. These results support clinical testing of this universal sarbecovirus vaccine for pandemic preparedness.

Spatiotemporal patterns of rabid dogs and cats and the opinions of personnel responsible for disease control in Thailand

The aim of this study was to evaluate the patterns of rabies cases in dogs and cats in Thailand from 2013 to 2016 via spatiotemporal analysis. We also assessed the opinions of responsible district-level personnel regarding risk factors and control measures for rabies. Evaluation of rabies case patterns was based on secondary data from a national online database, and a structured questionnaire was used to obtain the opinions of district-level personnel. A total of 1202 cases (1202/13058, 9.21 %) of rabid dogs and cats were documented between 2013 and 2016, with the majority of cases involving dogs (1165/13058; 8.92 %). The spatiotemporal analysis indicated that most of the cases were recorded in central Thailand and that there was a general trend of an increase in rabies cases from the beginning of 2013 to the end of 2016. Month-by-month analysis for each year suggested that the number of rabies cases tended to increase over the course of the year in 2013 and 2016. Results from the autocorrelation indicated that the correlation coefficient tended to be similar in adjacent time lags. In terms of the opinion analysis, only one factor (i.e., the presence of a forest that served as a habitat for carrier animals in the district) was statistically significant (P < 0.05) in the final binary logistic regression model. The results of this study may facilitate planning for effective rabies control in Thailand.

Leptospirosis in horses: Sentinels for a neglected zoonosis? A systematic review.

Leptospirosis is considered a neglected tropical zoonosis in low-income countries due to surveillance system limitations and non-specificity of symptoms. Humans become infected through direct contact with carrier animals or indirectly through Leptospira-contaminated environments. Conventionally, equines have been considered an uncommon source of leptospirosis, but recent publications in Latin America suggest that their role in the maintenance and dispersion of the bacteria could be more relevant than expected, as horses are susceptible to a wide variety of zoonotic Leptospira spp. from domestic and wild animals with which they share the environment. A systematic review of the published literature was conducted to compile the available information on Leptospira spp. in Ecuador, with a special focus on equine leptospirosis, to better understand the epidemiology of the bacterium and identify possible knowledge gaps. A systematic review of the published literature was conducted in PubMed, SciELO and Web of Science databases to compile the available information on Leptospira spp. in Ecuador, with a special focus on equine leptospirosis, to better understand the epidemiology of the bacterium. We used a combination of the terms (Leptospira OR Leptospirosis) AND Ecuador, without restrictions on language or publication date. Our literature review reveals that published scientific information is very scarce. Eighteen full-text original scientific articles related to Leptospira or leptospirosis cases in Ecuador were included in the systematic review. Most of the studies reported data obtained from one of the four regions (Coast), and specifically from only one of the 24 Provinces of Ecuador (Manabí), which evidence a large information bias at the geographical level. Furthermore, only the studies focused on humans included clinical signs of leptospirosis and there is only one study that analyzes the presence of Leptospira spp. in water or soil as a risk factor for pathogen transmission. Finally, only one study investigated Leptospira in horses. Since sentinel species can provide useful data on infectious diseases when epidemiologic al information is lacking, and horses could be considered excellent sentinel species to reveal circulating serovars, we propose developing a nationwide surveillance system using horses. This cost-effective epidemiological survey method provides a baseline for implementing specific prevention and control programs in Ecuador and neighboring developing countries.

Genomic approach to manage genetic variability in dairy farms

In this study we investigated the genetic variability, the inbreeding and allele frequencies of monogenic traits in seven herds of Holstein breed and provided insight to farmers on the value of genomic management of reproduction in their herds. A total of 3,953 Holstein cows were sampled and genotyped with the Neogen GGP Bovine 100K SNP chip within the activities of the Regione Lombardia funded GO-PEI project ‘GENOmic tool for the management of reproduction in dairy cattle and for the control of inbreeding – GENORIP’. Principal component analysis was applied for analysing the genetic variability within and among farms using the SVS software of Golden Helix. Run of Homozygosity (ROH) and the genomic inbreeding were obtained with the detectRUNS package of the R software. Genotype frequencies for mendelian disease, fertility and production traits were also obtained. A total of 458,267 ROH were identified and ROH were distributed on all autosomes with an average length of 2,703,811 bp covering 12.7% of the genome. Several genomic regions appear under selection, while a specific region on BTA4 was identified in one herd, harbouring genes mainly related to the specific selection strategy of the farmer. The FROH values obtained considering ROH greater than 16 Mb, varied from 0.004 to 0.325, with the highest FROH average value of 0.136. Among mendelian heritable diseases, the Haplotype Cholesterol Deficiency was the one with the largest proportion of carrier animals, i.e. 5.6%. A herd-tailored process to assist farmers in genomic management of reproduction was released. The ROH distribution within herd, together with the genotype frequencies for disease, fertility and production mendelian traits, suggest that similar directional selection is occurring across herds. This study released to each farmer the genomic make-up of their herd used jointly with the gEBV estimated by their national breeders’ association (ANAFIBJ) for herd reproductive management.

Use of milk samples in epizootic surveillance of cattle diseases

Relevance. The analysis of the possibility of using milk as a non-invasive type of samples in the epizootological control of diseases of cattle is given. During pathogenesis, many etiologic agents cause breast lesions or are excreted together with milk, which makes milk an ideal sample for laboratory diagnostics of infectious diseases of cattle, since it is available in any quantity and its samples are easy to collect.Methods. Conventional methods of document analysis were used.Results. It is shown that milk samples can be used both at the individual and at the population level for early identification of infected herds, screening of infected herds and use to obtain evidence of the well-being of herds. The availability of commercial diagnostic test systems for detecting antibodies in milk to the causative agents of leukemia of cattle, viral diarrhea of cattle, Brucella abortus, Mycobacterium avium subspecies paratuberculosis, Fasciola hepatica, Q fever (Coxiella burnetii) makes available programs for the control and eradication of diseases in dairy herds and at the level of countries. The use of combined non-invasive milk samples makes it possible to combat slowly progressive and chronic cattle infections of dairy cattle (bovine leucosis, paratuberculosis, brucellosis), and exclude carrier animals from the production chain in real time, which indicates the feasibility of introducing this type of samples into veterinary practice in the Russian Federation.

Heterogeneity and Recombination of Foot-and-Mouth Disease Virus during Multi-Strain Coinfection of Cattle.

Superinfection of cattle persistently infected with foot-and-mouth disease virus (FMDV), with a heterologous FMDV strain has been shown to generate novel recombinant viruses. In this study, we investigated the pathogenesis events within specific tissues associated with FMDV coinfections in cattle subjected to either simultaneous or serial exposure to two distinct strains of FMDV. Both strains of FMDV (one each of serotypes O and A) were similarly localized to the nasopharyngeal mucosa during the early stages of infection. However, while no recombinant FMDV genomes were recovered from simultaneously coinfected cattle, interserotypic recombinants were isolated from nasopharyngeal tissue samples obtained at 48 h after heterologous superinfection of a persistently infected FMDV carrier. Additionally, analysis of FMDV genomes obtained from replicate nasopharyngeal tissue samples demonstrated that adjacent segments of the mucosa were sometimes infected by distinct viruses, demonstrating a multifocal and heterogeneous distribution of FMDV infection during primary and persistent phases of infection. This work indicates that superinfection of FMDV carriers may be an important source of emergent recombinant strains of FMDV in areas where multiple strains are co-circulating. IMPORTANCE Foot-and-mouth disease (FMD) is a socioeconomically impactful livestock disease with a complex epidemiology and ecology. Although recombinant viruses have been identified in field samples, the mechanisms of emergence of those viruses have never been elucidated. This current study demonstrates how serial infection of cattle with two distinct serotypes of FMD virus (FMDV) leads to rapid generation of recombinant viruses in the upper respiratory tracts of infected animals. This finding is particularly relevant in relation to the management of persistently infected FMDV carrier cattle that can maintain subclinical FMDV infection for months to years after an initial infection. Such carrier animals may function as mixing vessels that facilitate the emergence of novel recombinant FMDV strains in areas where multiple virus strains are in circulation.

Prevalence of anaplasmosis and ehrlichiosis in reindeer of the nenets autonomous okrug

Vector-borne diseases pose a serious threat to the sanitary and epidemiological wellbeing of a person. As a rule, the source of pathogens of this group of diseases is considered to be carrier animals that can keep the pathogen in their body for life. Changing climate conditions lead to changes in the habitat of insect vectors, which inevitably leads to the expansion of the geographical boundaries of vector-borne infections. The aim of the work is to study the prevalence of anaplasmosis and ehrlichiosis among reindeer of the Nenets Autonomous Okrug. The material for the research was stabilized EDTA venous blood from reindeer (Rangifer tarandus) of the Nenets breed. The diagnosis was established by PCR. It has been proved that the infection of reindeer with anaplasmosis averages 14.3%, while vazhenki have the greatest extent of invasion – 21.4%, while males and calves are less affected by the pathogen (9.1% and 12.5%, respectively). Infection of animals with ehrlichiosis turned out to be more significant: DNA of ehrlichiae was present in 44.9% of samples, while the infection of vazhenok was 57.1%, calves – 37.5%, choirs – 45.5%. The morphological composition of the blood of healthy and infected reindeer had no significant differences in a number of indicators, which indicates a latent chronic course of the disease. Thus, the results of the work indicate that anaplasmosis and ehrlichiosis are widespread among reindeer living on the territory of the Low-Earth tundra, which serve as a natural reservoir for these pathogens.