Important Disease Of Cattle Research Articles

Rapid Spread and Genetic Characterisation of a Recently Emerged Recombinant Lumpy Skin Disease Virus in Thailand.

Simple SummaryLumpy skin disease (LSD) is an economically important disease of cattle caused by LSD virus (LSDV), a member of poxviruses. It had never been found in Thailand before March 2021, but has since spread broadly to various provinces. Regional veterinarians have collected samples from the LSD cattle and submitted them for diagnosis as a part of disease surveillance during the outbreaks. Our study aimed to monitor the distribution of the outbreaks by recording the LSD cases based on clinical signs and laboratory tests up to June 2022, and characterise the causative agent virologically and genetically. Outbreak maps were created to illustrate the rapid temporal distribution of the LSD index cases in each province of Thailand. We detected two distant origins of the outbreaks. LSDV DNA was confirmed in blood, milk, and skin samples collected from sick animals by real-time PCR. LSDV was proven to be the causative virus based on serological, virological, and pathological diagnoses. By genetic analysis, the Thai LSDV is a recombinant virus derived from a vaccine strain previously appearing in China and Vietnam. Its genetic material is a mosaic hybrid genome containing the vaccine virus DNA as the backbone interspersed with DNA fragments of a field strain.The emergence of the lumpy skin disease virus (LSDV) was first detected in north-eastern Thailand in March 2021. Since then, the abrupt increase of LSD cases was observed throughout the country as outbreaks have spread rapidly to 64 out of a total of 77 provinces within four months. Blood, milk, and nodular skin samples collected from affected animals have been diagnosed by real-time PCR targeting the p32 gene. LSDV was isolated by primary lamb testis (PLT) cells, followed by Madin-Darby bovine kidney (MDBK) cells, and confirmed by immunoperoxidase monolayer assay (IPMA). Histopathology and immunohistochemistry (IHC) of a skin lesion showed inclusion bodies in keratinocytes and skin epithelial cells. Phylogenetic analyses of RPO30 and GPCR genes, and the whole genome revealed that Thai viruses were closely related to the vaccine-derived recombinant LSDV strains found previously in China and Vietnam. Recombination analysis confirmed that the Thai LSDV possesses a mosaic hybrid genome containing the vaccine virus DNA as the backbone and a field strain DNA as the minor donor. This is an inclusive report on the disease distributions, complete diagnoses, and genetic characterisation of LSDV during the first wave of LSD outbreaks in Thailand.

Morphological and Phenotypic Characteristics of the Bovine Nasopharyngeal Mucosa and Associated Lymphoid Tissue

The mammalian nasopharynx is an anatomically complex region of the upper respiratory tract that directly communicates with the nasal cavity, laryngopharynx, oesophagus and trachea. The nasopharyngeal mucosa contains moderate quantities of mucosa-associated lymphoid tissue (MALT) that is appropriately located for immunological sampling but also creates vulnerability to pathogens. In recent years, the nasopharynx has been inculpated in the pathogenesis of important diseases of cattle (foot-and-mouth disease) and humans (COVID-19), yet the tissue has never been described in detail in any species. In order to characterize the morphology and cellular composition of the bovine nasopharynx, samples of mucosa were collected from the nasopharynx of five 8-13-month-old steers and examined using light microscopy, immunohistochemistry and multichannel immunofluorescence. Morphologically, the nasopharyngeal epithelium was highly heterogeneous, with a continuum ranging from stratified squamous epithelium to highly attenuated, follicle-associated epithelium (FAE). Distribution of MALT was similarly regionally variable ranging from absent to clusters of multiple lymphoid follicles. Phenotypic characterization demonstrated dense distributions of dendritic cells and T lymphocytes surrounding lymphoid follicles, which comprised mostly B lymphocytes. The FAE overlaying the lymphoid follicles also contained higher numbers of dendritic cells and lymphocytes compared with the adjacent non-lymphoid epithelium, although cytotoxic T cells were notably scarce in the FAE. The bovine nasopharyngeal lymphoid tissue had comparable elements to other MALTs with specific differences that may help to elucidate the pathogenesis of infectious agents that have specific tropism for this tissue.

Downregulation of the Long Noncoding RNA IALNCR Targeting MAPK8/JNK1 Promotes Apoptosis and Antagonizes Bovine Viral Diarrhea Virus Replication in Host Cells.

Bovine viral diarrhea virus (BVDV) is the causative agent of the bovine viral diarrhea-mucosal disease, which is a leading cause of economic losses in the cattle industry worldwide. To date, many underlying mechanisms involved in BVDV-host interactions remain unclear, especially the functions of long noncoding RNAs (lncRNAs). In our previous study, the lncRNA expression profiles of BVDV-infected Madin-Darby bovine kidney (MDBK) cells were obtained by RNA-seq, and a significantly downregulated lncRNA IALNCR targeting MAPK8/JNK1 (a key regulatory factor of apoptosis) was identified through the lncRNA-mRNA coexpression network analysis. In this study, the function of IALNCR in regulating apoptosis to affect BVDV replication was further explored. Our results showed that BVDV infection-induced downregulation of the lncRNA IALNCR in the host cells could suppress the expression of MAPK8/JNK1 at both the mRNA and protein levels, thereby indirectly promoting the activation of caspase-3, leading to cell-autonomous apoptosis to antagonize BVDV replication. This was further confirmed by the small interfering RNA (siRNA)-mediated knockdown of the lncRNA IALNCR. However, the overexpression of the lncRNA IALNCR inhibited apoptosis and promoted BVDV replication. In conclusion, our findings demonstrated that the lncRNA IALNCR plays an important role in regulating host antiviral innate immunity against BVDV infection. IMPORTANCE Bovine viral diarrhea-mucosal disease caused by BVDV is an important viral disease in cattle, causing severe economic losses to the cattle industry worldwide. The molecular mechanisms of BVDV-host interactions are complex. To date, most studies focused only on how BVDV escapes host innate immunity. By contrast, how the host cell regulates anti-BVDV innate immune responses is rarely reported. In this study, a significantly downregulated lncRNA, with a potential function of inhibiting apoptosis (inhibiting apoptosis long noncoding RNA, IALNCR), was obtained from the lncRNA expression profiles of BVDV-infected cells and was experimentally evaluated for its function in regulating apoptosis and affecting BVDV replication. We demonstrated that downregulation of BVDV infection-induced lncRNA IALNCR displayed antiviral function by positively regulating the MAPK8/JNK1 pathway to promote cell apoptosis. Our data provided evidence that host lncRNAs regulate the innate immune response to BVDV infection.

Identification of Key Genes and Potential Pathways Associated with Mastitis Induced by E. coli.

Mastitis is one of the most important diseases of dairy cattle. It is an infectious disease leading to an inflammatory reaction in the cow's mammary gland. Escherichia coli is one of the common bacteria which induce mastitis in cows. The aim of this study was to identify key genes and potential pathways associated with mastitis induced by E. coli in dairy cattle using bioinformatics analysis. The gene expression profile of ten samples including five adjacent tissues from a quarter infected with Escherichia coli and five tissues from a healthy quarter of dairy cattle was assessed using GEO2R. Gene ontology and pathway analysis were performed using bioinformatics tools. A total of 156 differentially expressed genes were detected which 95 genes were upregulated and 61 genes were downregulated in adjacent tissue of quarter infected compared with healthy tissue. Cellular oxidant detoxification and oxidation–reduction process were the most significant biological process terms in gene ontology analysis. The most important pathways of DEGs were the biosynthesis of amino acids, p53 signaling pathway, and Metabolic pathways. Three important modules were identified and their path enrichment analysis was performed. There are 10 core genes, among which SOD2, COL1A2, COL3A1, POSTN, ALDH18A1, and CBS may be the main genes associated with mastitis, which can be considered as candidate genes in the prevention and carly diagnosis program of mastitis.

Ruminant health research – progress to date and future prospects, with an emphasis on Irish research

This review addresses the progress that has been made in ruminant health research over the last 60 yr, with an emphasis on Irish research. The review focuses on the economically important infectious diseases of dairy and beef cattle and of sheep, calf diseases, regulated and non-regulated infectious diseases, lameness, mastitis and parasitoses. The progress to date, current knowledge and future challenges are all addressed. Paradigm shifts have occurred in many of these diseases, the most profound of which is the change from increasing antimicrobial usage (AMU) to the realisation of the challenge of antimicrobial resistance (AMR) and the current reduction in AMU. Another major change in thinking is the move away from focus on the pathogen exclusively towards a more holistic view of the roles of host immunity and adequacy of management. In the last 60 yr, many new diseases have emerged but in parallel many new technologies have rapidly evolved to monitor and control these threats to animal health. Irish research has contributed substantially to improved current ruminant health. The major future challenge is how to manage ruminant health in a OneHealth world where animal, human and environmental health and sustainability are intimately intertwined and interdependent.

A locus conferring tolerance to Theileria infection in African cattle.

East Coast fever, a tick-borne cattle disease caused by the Theileria parva parasite, is among the biggest natural killers of cattle in East Africa, leading to over 1 million deaths annually. Here we report on the genetic analysis of a cohort of Bos indicus (Boran) cattle demonstrating heritable tolerance to infection with T. parva (h2 = 0.65, s.e. 0.57). Through a linkage analysis we identify a 6 Mb genomic region on bovine chromosome 15 that is significantly associated with survival outcome following T. parva exposure. Testing this locus in an independent cohort of animals replicates this association with survival following T. parva infection. A stop gained variant in a paralogue of the FAF1 gene in this region was found to be highly associated with survival across both related and unrelated animals, with only one of the 20 homozygote carriers (T/T) of this change succumbing to the disease in contrast to 44 out of 97 animals homozygote for the reference allele (C/C). Consequently, we present a genetic locus linked to tolerance of one of Africa's most important cattle diseases, raising the promise of marker-assisted selection for cattle that are less susceptible to infection by T. parva.

Isolation and Molecular Detection of Lumpy Skin Disease Virus from Outbreak Cases in Illubabor Zone, Oromia Regional State, Ethiopia

Background: Lumpy skin disease is one of the most economically important viral diseases of cattle and Asian water buffalo caused by lumpy skin disease virus, which occurs in most African countries including Ethiopia. In Ethiopia, it has been detected in exotic and local breed cattle. To this end, there is scarcity of information on its epidemic status, among cattle in Illubabor, Ethiopia. Therefore, outbreak investigation was conducted to estimate epidemic status of lumpy skin disease among cattle in illubabor zone, Yayo district. Methodology: Outbreak investigation was done from August to December 2020 in the Ilubabor zone, Yayo district, with the goal of isolating and detecting the virus using molecular methods. All ages and both sexes of local breed cattle from reported disease outbreaks of the study area were subjected to the study. Skin biopsies (n=44) were collected from non-vaccinated lumpy skin disease affected cattle after examining the presence of skin lesions and transported to NAHDIC for laboratory test. Virus was isolated by growing on Vero cells and molecular detection was performed by conventional and real-time polymerase chain reaction. Results: The characteristic capripoxvirus cytopathic effect was observed on 17 out of 44 Vero cells inoculated. Out of the total 44 samples, 88.63% (39/44) and (95.45%) 42/44 were found positive for LSDV by conventional and real time polymerase chain reaction respectively. Chi-square (x²) test was used to assess the association of sex and ages with affected group. Morbidity, mortality and case fatality rates were 15.49%, 1.4% and 9.09% respectively. Adult cattle showed higher morbidity (17.18%) than young ones (11.1%). Also not statistically significant, higher morbidity was observed in female (16.66%) than male (14.11%) cattle. Conclusion: The study showed that lumpy skin disease was circulating in cattle in the area and causing great loss to the farmers with high morbidity rates. To reduce economic losses caused by the disease, it was suggested that strategic programs for effective control and prevention be established.

Integrative Transcriptomics and Proteomics Analysis Provide a Deep Insight Into Bovine Viral Diarrhea Virus-Host Interactions During BVDV Infection.

Bovine viral diarrhea virus (BVDV) is the causative agent of bovine viral diarrhea-mucosal disease (BVD-MD), an important viral disease in cattle that is responsible for extensive economic losses to the cattle industry worldwide. Currently, several underlying mechanisms involved in viral replication, pathogenesis, and evading host innate immunity of BVDV remain to be elucidated, particularly during the early stage of virus infection. To further explore the mechanisms of BVDV-host interactions, the transcriptomics and proteomics profiles of BVDV-infected MDBK cells were sequenced using RNA-seq and iTRAQ techniques, respectively, and followed by an integrative analysis. Compared with mock-infected MDBK cells, a total of 665 differentially expressed genes (DEGs) (391 down-regulated, 274 up-regulated) and 725 differentially expressed proteins (DEPs) (461 down-regulated, 264 up-regulated) were identified. Among these, several DEGs and DEPs were further verified using quantitative RT-PCR and western blot. Following gene ontology (GO) annotation and KEGG enrichment analysis, we determined that these DEGs and DEPs were significantly enriched in multiple important cellular signaling pathways including NOD-like receptor, Toll-like receptor, TNF, NF-κB, MAPK, cAMP, lysosome, protein processing in endoplasmic reticulum, lipid metabolism, and apoptosis signaling pathways. Significantly, the down-regulated DEGs and DEPs were predominantly associated with apoptosis-regulated elements, inflammatory factors, and antiviral elements that were involved in innate immunity, thus, indicating that BVDV could inhibit apoptosis and the expression of host antiviral genes to facilitate viral replication. Meanwhile, up-regulated DEGs and DEPs were primarily involved in metabolism and autophagy signaling pathways, indicating that BVDV could utilize the host metabolic resources and cell autophagy to promote replication. However, the potential mechanisms BVDV-host interactions required further experimental validation. Our data provide an overview of changes in transcriptomics and proteomics profiles of BVDV-infected MDBK cells, thus, providing an important basis for further exploring the mechanisms of BVDV-host interactions.

A Serosurvey for Ruminant Pestivirus Exposure Conducted Using Sera From Stray Mexico Origin Cattle Captured Crossing Into Southern Texas.

The US Department of Agriculture (USDA), Animal Plant Health Inspection Service (APHIS), Cattle Fever Tick Eradication Program (CFTEP) monitor a quarantine zone along the Texas border to prevent the introduction of stray livestock carrying cattle fever ticks entering the United States from Mexico. Stray cattle collected by CFTEP are checked for ticks and several infectious disease-causing pathogens, but not for bovine viral diarrhea virus (BVDV). BVDV is one of the most economically impactful viruses affecting US cattle producers. BVDV is present in all parts of the world, but it has been demonstrated that another distantly related pestivirus, HoBi-like pestivirus (HoBiPev), can also cause BVD. To date, HoBiPev has not been detected in the United States, but is commonly found in Brazil, and sporadically in Europe and Asia. The objective of the current study was to evaluate the seroprevalence of pestiviruses, with a specific focus on HoBiPev, in stray cattle. Virus neutralization (VN) assay was used to determine seroprevalence (or antibody titers) of BVDV-1, BVDV-2, and HoBiPev. Approximately 50% (67 of 134) of the samples were seropositive for pestiviruses; all 67 positive samples were positive (50%) for BVDV-1, 66 samples of the 67 were positive (49.3%) for BVDV-2, and the same 66 samples of the 67 were also positive (49.3%) for HoBiPev. Due to the antigenic cross-reactivity among Pestiviruses, the comparative antibody against each pestivirus was calculated from all VN-positive samples. Titers were clearly higher against BVDV-1, and only one sample had a titer clearly higher against BVDV-2. No sample had an antibody titer higher for HoBiPev, and while this does not prove the absence of HoBiPev, it does provide evidence that the prevalence of HoBiPev is less predominant than BVDV-1. Additionally, data from these samples provide evidence on the susceptibility of animals that may enter into the United States, with ~50% of the animals seronegative for bovine pestiviruses. This cattle population provides a unique opportunity to evaluate and monitor changes in seroprevalence of economically important cattle diseases affecting the cattle industry.

Description of infectious bovine keratoconjunctivitis outbreaks in West Virginia beef herds

Infectious bovine keratoconjunctivitis (IBK) is the most important ocular disease of cattle. Prevention and control of the disease can prove challenging, and the list of potential etiologic agents has expanded in recent years. Little has been recently published characterizing IBK outbreaks at the herd level. This case series investigation was conducted to describe the disease characteristics and management practices in herds affected by IBK outbreaks in 1 practice area in West Virginia in 2019. Seven producers were interviewed: 6 cowcalf producers and 1 stocker producer. Producers were asked questions pertaining to disease severity and management, such as herd health protocols and husbandry. In addition, organisms from each of the herds were identified by culture and/or PCR. Results revealed a range of disease incidence as well as similarities and differences in management practices among herds. The interpretability of results is limited due to small sample size and data collection method; however, results suggest that some herds in the area where producerswere interviewed experienced severe IBK outbreaks, and that some management practices relevant to IBK were similar between herds. Results also suggest that further study to identify poorly characterized IBK risk factors is warranted.

Seasonal analysis of leptospirosis in apparently healthy dairy cattle of Pananchery panchayat in Thrissur district, Kerala

Leptospirosis is an economically important zoonotic bacterial disease of cattle with global distribution. The present study investigated the seroprevalence and distribution of leptospiral serovars in cattle population in Pananchery panchayat of Thrissur district, Kerala. From 52 apparently healthy dairy cattle, serum samples were collected in both pre-monsoon and postmonsoon seasons. All samples were subjected to microscopic agglutination test (MAT) against 13 serovars of Leptospira spp. Among the samples tested, 13 (25 per cent) samples in pre-monsoon and 19 (36.54 per cent) samples in post-monsoon were found to be positive. The predominant serovars detected in pre-monsoon were Hardjo (29.41 per cent) followed by Grippotyphosa (17.64 per cent), Bataviae and Pomona (11.76 per cent each). Similarly in post-monsoon, Hardjo (28.57 per cent) followed by Grippotyphosa (23.81 per cent), and Bataviae (19.05 per cent) were identified as the most common serovars. Higher seroprevalence of disease in apparently healthy cattle in post-monsoon compared to pre-monsoon indicate the influence of rainfall on occurrence of leptospirosis.

Mycoplasma bovis Mastitis.

Bovine mycoplasmoses, which is mostly caused by Mycoplasma bovis, is a significant problem in the dairy and beef industry. Mycoplasmal mastitis has a global occurrence with notable effects in the United States and Europe. The pathogen was first detected in a mastitis case in California, United States, and regarded as major contagious mastitis. It is highly contagious and resistant to antibiotics and lack cell wall rendering certain group of antibiotics ineffective. Outbreaks mostly originate from introduction of diseased dairy cows to a farm and poor hygienic practices that help to maintain cow to cow transmission. Rapid detection scheme is needed to be in place in dairy farms to devise preventive measures and stop future outbreaks. However; early detection is hampered by the fastidious growth of M. bovis and the need for specialized equipment and reagents in laboratory settings. Intramammary Mycoplasma bovis infections cause elevation in milk somatic cell count which is one of the important factors to determine milk quality for grading and hence dictates milk price. There are multiple attributes of M. bovis regarded as virulence factors such as adhesion to and invasion into host cells, avoidance of phagocytosis, resistance to killing by the alternative complement system, biofilm formation, and hydrogen peroxide production. Nevertheless, there are still undetermined virulence factors that hamper the development of sustainable control tools such as effective vaccine. To date, most vaccine trials have failed, and there is no commercial M. bovis mastitis vaccine. Mycoplasma bovis has been shown to modulate both humoral and cellular immune response during bovine mastitis. In the future, research seeking new immunogenic and protective vaccine targets are highly recommended to control this important dairy cattle disease worldwide.

A description of infectious bovine keratoconjunctivitis outbreaks in West Virginia beef herds

Infectious bovine keeratoconjuctivitis (IBK) is the most important ocular disease of cattle. Prevention and control of the disease can prove challengin, and the list of potential etiologic agens has expanded in recent years. Little has been recently published characterizing IBK outbreaks at the herd level. This case series investigation was conducted to describe the disease characteristics and management practices in herds affected by IBK outbreaks in 1 practice area in West Virginia in 2019. Seven producers were interviewed: 6 cow-calf producers and 1 stocker producer. Prdocuers were asked questions pertaining to disease severity and management, such as herd health protocols and husbandry. In addition, organisms from each of the herds were identified by culture and/or PCR. Results revealed a range of disease incidence as well as similarities and differences in management practices among herds. The interpretability of results is limted due to small sample size and data colelction method; however, results suggest that some herds in the area where producers were interviewed experienced severe IBK outbreaks, and that some management practices relevant to IBK were similar between herds. Results also suggest that further study to identify poorly characterized IBK risk factors is warrented.

Prevalence of Coccidia in sheep at the Bauchi Abattoir, Inkil, Bauchi state

Coccidiosis is a disease that destroys the intestinal mucosa which is caused by the protozoa parasites of the genus Eimera or Isospora species. The symptoms include diarrhoea, fever, weight loss, emaciation and consequently, death. Many infections are subclinical (that is, not severe enough to cause readily observable symptoms). Coccidiosis is an economically important disease of cattle, sheep, goats, pigs, poultry and also rabbits, in which the liver and intestine are affected. In dogs, cats, and horses, coccidiosis is less often diagnosed but can result in clinical illness.

Study of clinical signs and post mortem changes in vaccinated and unvaccinated buffaloes experimentally infected with the virulent Pasturella multocida bacterium that causes hemorrhagic septicemia in buffaloes-South of Iraq .

Hemorrhagic septicemia is an important disease of cattle and buffaloes. Which causes disease revolutions with great economic losses in Asia and Africa, and in Iraq it is considered one of the more dangerous diseases in buffaloes than in cows. This study was prepared to reassess the vaccination program against hemorrhagic septicemia, which is used in Iraq, especially in buffaloes, due to the nature of their lives in the marshes and as a result of the epidemic that occurred in 2008 by conducting a challenge test on buffaloes directly with a study of some physiological and immunological aspects before and after examining the challenge, as well as the effect of virulent germ The animal body has clinical symptoms and pathological changes when the post mortem is performed. This study has the advantage of using the buffalo itself by performing the challenge assay directly on it. We can depend on animal mortality, clinical symptoms and local interaction to distinguish animal resistance to the challenge test and the efficacy of the vaccine type in immunization of buffaloes against hemorrhagic septicemia. Clinical and pathological symptoms may be used on the field diagnosis of the disease and are considered as enhancement for bacterial diagnosis.

Coding-Complete Sequences of Recombinant Lumpy Skin Disease Viruses Collected in 2020 from Four Outbreaks in Northern Vietnam.

ABSTRACTLumpy skin disease virus (LSDV) causes a severe, systemic, and economically important disease in cattle. Here, we report coding-complete sequences of recombinant LSDVs from four outbreaks in October and November 2020 in northeastern Vietnam.

Incidence of Contagious Bovine Pleuropneumonia in Livestock of Pothohar Plateau Punjab, Pakistan

Mycoplasma mycoides variant mycoides causes contagious bovine pleuropneumonia (CBPP), an important infectious disease of cattle’s respiratory system. To determine the prevalence of CBPP, a cross-sectional study was done in the Pothohar plateau (districts Rawalpindi, Attock and Jhelum) Punjab. Using a sandwich enzyme-linked immunosorbent assay, 850 serum samples were tested for specific antibodies against M. mycoides subspecies mycoides. Age, gender, and breed were all examined as potential risk factors. The overall prevalence in this study was 17.65%. CBPP prevalence was 14.62%, 17.50%, and 20.32% in districts Rawalpindi, Attock and Jhelum, respectively, with significant difference (P<0.05). Gender and breed were not substantially connected with the animal’s serological status (P<0.05) among the investigated putative predisposing factors, however age was strongly associated with CBPP positivity (P<0.05). Positivity was highest in animals over 7 years of age (27.78%), followed by 4-6 years of age (15.65%), and lowest in animals under 4 years of age (13.33%). This study establishes the prevalence of CBPP in the state, which could pose a threat to the state’s cattle export market and necessitates the development of control measures to reduce the disease’s economic losses.

Inherited Tolerance in Cattle to the Apicomplexan Protozoan Theileria parva is Associated with Decreased Proliferation of Parasite-Infected Lymphocytes.

Theileria parva is the causative agent of East Coast fever and Corridor disease, which are fatal, economically important diseases of cattle in eastern, central and southern Africa. Improved methods of control of the diseases are urgently required. The parasite transforms host lymphocytes, resulting in a rapid, clonal expansion of infected cells. Resistance to the disease has long been reported in cattle from T. parva-endemic areas. We reveal here that first- and second-generation descendants of a single Bos indicus bull survived severe challenge with T. parva, (overall survival rate 57.3% compared to 8.7% for unrelated animals) in a series of five field studies. Tolerant cattle displayed a delayed and less severe parasitosis and febrile response than unrelated animals. The in vitro proliferation of cells from surviving cattle was much reduced compared to those from animals that succumbed to infection. Additionally, some pro-inflammatory cytokines such as IL1β, IL6, TNFα or TGFβ which are usually strongly expressed in susceptible animals and are known to regulate cell growth or motility, remain low in tolerant animals. This correlates with the reduced proliferation and less severe clinical reactions observed in tolerant cattle. The results show for the first time that the inherited tolerance to T. parva is associated with decreased proliferation of infected lymphocytes. The results are discussed in terms of whether the reduced proliferation is the result of a perturbation of the transformation mechanism induced in infected cells or is due to an innate immune response present in the tolerant cattle.

Bovine Leukaemia Virus: Current Epidemiological Circumstance and Future Prospective

Bovine leukaemia virus (BLV) is a deltaretrovirus that is closely related to human T-cell leukaemia virus types 1 and 2 (HTLV-1 and -2). It causes enzootic bovine leukosis (EBL), which is the most important neoplastic disease in cattle. Most BLV-infected cattle are asymptomatic, which potentiates extremely high shedding rates of the virus in many cattle populations. Approximately 30% of them show persistent lymphocytosis that has various clinical outcomes; only a small proportion of animals (less than 5%) exhibit signs of EBL. BLV causes major economic losses in the cattle industry, especially in dairy farms. Direct costs are due to a decrease in animal productivity and in cow longevity; indirect costs are caused by restrictions that are placed on the import of animals and animal products from infected areas. Most European regions have implemented an efficient eradication programme, yet BLV prevalence remains high worldwide. Control of the disease is not feasible because there is no effective vaccine against it. Therefore, detection and early diagnosis of the disease are essential in order to diminish its spreading and the economic losses it causes. This review comprises an overview of bovine leukosis, which highlights the epidemiology of the disease, diagnostic tests that are used and effective control strategies.

Review: Vaccines and Vaccination against Lumpy Skin Disease.

The geographical distribution of lumpy skin disease (LSD), an economically important cattle disease caused by a capripoxvirus, has reached an unprecedented extent. Vaccination is the only way to prevent the spread of the infection in endemic and newly affected regions. Yet, in the event of an outbreak, selection of the best vaccine is a major challenge for veterinary authorities and farmers. Decision makers need sound scientific information to support their decisions and subsequent actions. The available vaccine products vary in terms of quality, efficacy, safety, side effects, and price. The pros and cons of different types of live attenuated and inactivated vaccines, vaccination strategies, and associated risks are discussed. Seroconversion, which typically follows vaccination, places specific demands on the tools and methods used to evaluate the effectiveness of the LSD vaccination campaigns in the field. We aimed to give a comprehensive update on available vaccines and vaccination against LSD, to better prepare affected and at-risk countries to control LSD and ensure the safe trade of cattle.