Non-vaccinated Cattle Research Articles

Prevalence of lumpy skin disease in cattle at Netrokona sadar in Bangladesh

Cattle farming is a significant contributor to the socio-economic development of Bangladesh. However, infectious diseases continuously challenge cattle farming, causing tremendous losses to farmers. Among the diseases, Lumpy Skin Disease (LSD) has become a major burden in recent years. This study was conducted to reveal the prevalence of LSD in cattle in Netrokona Sadar Upazila. Data were collected directly from the cattle farmers at Upazila Veterinary Hospital (UVH), by visiting farms, and retrospectively from the register book of UVH from November 2022 to October 2023. Of the total of 2511 observed cattle, the prevalence of LSD was the second highest (16.97%). We further investigated the prevalence of LSD according to age, sex, breed, season, vaccination status, nutrition, hygiene, and deworming. LSD was more prevalent in young (17.67%), females (18.25%), cross-breed (23.96%), and non-vaccinated (17.28%) cattle. A higher prevalence was also found in the summer (38.77%) than in other seasons. Furthermore, we found more prevalence in cattle provided with traditional diets (18.22%), in unhygienic management (17.33%), and non-dewormed (18.63%) cattle. The findings illustrated that sex, immunization status, season of the year, and diet were significantly (p<0.01) associated with the prevalence of LSD. The study will aid stakeholders in evaluating the current state of LSD in the area and developing effective control strategies against it. Res. Agric. Livest. Fish. Vol. 11, No. 2, August 2024: 137-147

Molecular Characterisation and Antibody Response to Bovine Respiratory Syncytial Virus in Vaccinated and Infected Cattle in Turkey.

Bovine respiratory syncytial virus (BRSV) is one of the most important respiratory pathogens of cattle. In this study, frequency of infection, analysis of variants, and the immune status of vaccinated and non-vaccinated cattle were studied. Blood (n = 162) and nasal/oropharyngeal (n = 277) swabs were collected from 62 cattle herds in Turkey. Lung samples (n = 37) were also taken from dead animals and abattoirs. Antibodies to BRSV were detected in 76 (46%) out of 162 sera. The antibody levels in the vaccinated and non-vaccinated groups were statistically significant. Among 277 nasal/oropharyngeal swabs and 37 lungs, ten nasal/oropharyngeal and four lung samples were positive for BRSV-RNA. BRSV-G gene sequences of 5 out of 14 RT-PCR positive samples showed that all viruses clustered as Group-III in phylogenetic analysis with 88-100% homology. Similarity with previous Turkish BRSVs was 89-98%, and that with BRSVs detected in the USA and Czechia was 89.47-93.12%. BRSV continues to circulate in Turkish cattle, and vaccination seems beneficial in preventing BRSV. The diversity of the BRSVs found in this study needs be considered in vaccination strategies.

Prevalence and risk factor analysis of lumpy skin disease in cattle population of Banskhali Upazila, Chattogram, Bangladesh

Objective: This investigation aimed at assessing the outbreak scenario of the disease in Banskhali Upazila, Chattogram district, Bangladesh. The epidemic was recorded in several areas of Bangladesh, but Banskhali Upazila was rarely mentioned in references. The study evaluated clinical features, and treatment protocol and identified risk factors associated with lumpy skin disease (LSD) in the cattle population of the study area. Materials and Methods: In the four months leading up to December 2020, 53 incidents involving cattle of four different ages and two different breeds were observed in Upazila Veterinary Hospital (UVH), Banskhali, Chattogram. 19 of them had been presumptively diagnosed with LSD based on the owners’ complaints, clinical histories, skin lesions unique to LSD, and associated risk factors. Results: The overall clinical prevalence of LSD was 35.85%, with a mortality rate of 1.88%. Fever and distinctive skin nodules were consistently noted at the highest frequency in affected cattle. Male (39.39%), crossbred (19.35%), and non-vaccinated (40%) cattle showed a significantly higher prevalence of the disease compared to their counterparts. Autohemotherapy, coupled with the administration of the antiviral drug acyclovir, systemic antibiotics such as streptopenicillin (36.84%), and the use of analgesics, anti-inflammatory agents, and antihistamines, were routinely utilized as supportive treatments for the disease. Conclusion: Strict quarantine, vector control, recording of outbreak pattern recording, and prophylactic vaccination may be the best treatments for lowering the disease’s risk factors for the disease. These findings may provide essential groundwork for further investigations to prevent further relapses or outbreaks of LSD in the future.

Comparative study of the ELISA use with milk and blood serum for bovine brucellosis diagnosis

Enzyme immunoassay, being a more sensitive method, makes it possible to identify specific antibodies in samples of combined milk. The ELISA study of harvested milk in farms can become an important element in the system of anti-brucellosis measures regarding the control of the epizootic state in farms taking into account the availability and ease of implementation of this method. For screening express-diagnostics of bovine brucellosis the method of enzyme immunoassay with milk of cows has been developed. ELISA with milk serum is specific, sensitive, easy to formulate, account for and interpret the results. It has been found that the conditions of storage and transportation of milk samples corresponding to room temperature values and leading to fermentation do not affect the level of specific anti-viral immunoglobulins for eight days, and the question of the use of a cold chain during transportation of milk samples to be examined to the place of analysis can be withdrawn from the agenda. When working out the optimal sample preparation, the difference in the specific signal when setting the ELISA between the milk serum obtained by high-speed centrifugation and the milk serum obtained by fermentation for 24 hours was less than 10%. Therefore, high-speed centrifugation was chosen for the preparation of milk serum samples during the ELISA study. The possibilities of using ELISA with milk serum on vaccinated and non-vaccinated cattle against brucellosis have been studied. Milk and blood for testing in the ELISA should be taken 6 months or more after vaccination (within the instructional time frame). A high level of correlation was established between ELISA data with milk and ELISA data with blood serum, regardless of epizootic or immune status (satisfactory and unfavorable herds, vaccinated and unvaccinated animals), which amounted to 86.8–92.0%.

Seroprevalence and Identification of Brucella melitensis Based on a Glycosyltransferase Gene among Ruminants in Rafha, Saudi Arabia

Brucellosis is a zoonotic disease with veterinary, public health, and economic implications. The study aimed to estimate the seroprevalence of Brucella spp. among ruminants in Rafha, Saudi Arabia during January to October 2022 and to identify camel strains based on a glycosyltransferase gene sequence. Sera (n=1012) were collected from non-vaccinated sheep, goats, camels and cattle of different sex, age and breed randomly from the abattoirs to investigate the circulating brucella antibodies using RBPT. One hundred and eighteen sera (9.7%) were reactive for Brucella spp. IgG immunoglobulins, with higher percentages detected in sheep (11.4%), females (13.3%), adults (10.7%), and naieme breed (13.9%). Significant correlation between Brucella spp. antibodies and animal species (0.095), age (0.077) was found, while strong correlation between antibodies and sex was observed. Glycosyltransferase gene was amplified and sequenced from camel reactive sera (n=6). Camel strains displayed multiple nucleotide substitutions and deletions, nucleotide identity among local strains is 96.2-100%. Phylogenetic analysis showed that Brucella spp. strains clustered in two groups, Rafha strains clustered in one group together with other strains. Further investigation is needed to determine the prevalence of the bacteria among farm animals and to identify the strains involved to improve the preventive measures and strategies adopted for control.

Effects of concurrent administration of modified live viral vaccines with RB51 on immune responses to RB51.

Brucella abortus is a gram negative, zoonotic pathogen that can cause abortions and stillbirths in the cattle industry and has contributed to significant economic losses to cow-calf producers. Cell mediated immunity (CMI) is an important component of the immune response associated with protection against Brucella abortus and other intracellular pathogens. Brucellosis and viral modified live vaccines (vMLV) are licensed individually but may be used concurrently under field conditions. Peripheral blood mononuclear cells (PBMC) from non-vaccinated cattle and cattle vaccinated with either Brucella abortus strain RB51, a vMLV or both RB51 and a vMLV vaccine were isolated. The frequency of CD4+, CD8+ and γδ+ T cell populations within PBMC, and the frequency of interferon gamma (IFN-γ) production within these cell types was characterized via flow-cytometry. The goal of this study was to characterize immune responses to RB51 vaccination and determine the effect of concurrent vaccine administration. Although immune responses were greatest in PBMC from cattle vaccinated with only RB51, cattle vaccinated with both RB51 and vMLV demonstrated measurable T cell responses associated with protective immunity. Data suggests a lack of significant biological differences between the groups in protective immune responses. Collectively, our data demonstrated a lack of vaccine interference following concurrent administration of vMLV and RB51. Although concurrent administration of individually licensed vaccines may influence immune responses and contribute to vaccine interference, potential vaccine combinations should be evaluated for biological effects.

East Coast Fever Carrier Status and Theileria parva Breakthrough Strains in Recently ITM Vaccinated and Non-Vaccinated Cattle in Iganga District, Eastern Uganda

East Coast fever (ECF) is a tick-borne disease of cattle that hinders the development of the livestock industry in eastern, central and southern Africa. The 'Muguga cocktail' live vaccine, delivered by an infection and treatment method (ITM), remains the only immunisation strategy of controlling ECF. However, there are challenges of the live vaccine inducing ECF carrier status in immunised animals and the possibility of lack of protection from parasite strains that are antigenically different from the vaccine strains. In Uganda, there are insufficient data regarding the ECF carrier status and T. parva genetic diversity in vaccinated and associated non-vaccinated cattle to assess the effectiveness of ITM vaccination. Blood was collected from recently ECF vaccinated (98) and non-vaccinated (73) cattle from Iganga district in Eastern Uganda at 120 days post-vaccination. The p104 gene nested PCR was used to screen for T. parva DNA, 11 minisatellite and 3 microsatellite markers (SSR) were used for genotyping. Two minisatellite markers (MS7 and MS19) were used to determine whether ECF carrier status was due to the T. parva vaccine or local strains. The prevalence of T. parva based on p104 nPCR was 61.2% (60/98) (RR 2.234, 95% CI 1.49-3.35, p-value < 0.001) among recently vaccinated cattle and 27.4% (20/73) (RR 1.00) among associated non-vaccinated cattle. The Muguga cocktail vaccine strains were responsible for carrier status in 10 (58.8%) by MS7 and 11 (64.7%) by MS19 in vaccinated cattle. Genotypes of T. parva with different-sized alleles to the vaccine strains that could be potential 'breakthroughs' were detected in 2 (11.8%)) and 4 (23.5%) isolates from vaccinated cattle based on MS7 and MS19 minisatellite markers, respectively. Using 14 SSR markers, T. parva diversity was higher in vaccinated (Na = 2.214, Ne = 1.978, He = 0.465) than associated non-vaccinated (Na = 1.071, Ne = 1.048, He = 0.259) cattle. The principal component analysis (PCA) showed isolates from vaccinated cattle were closely related to those from non-vaccinated cattle. The analysis of molecular variance (AMOVA) revealed high genetic variation (96%) within T. parva isolates from vaccinated and non-vaccinated cattle but low variation (4%) between vaccinated and non-vaccinated cattle. This study reveals the role of ITM in inducing the carrier status and higher T. parva genetic diversity in vaccinated cattle. The low genetic variation between T. parva isolates in both vaccinated and non-vaccinated cattle may be suggestive of the protective role of vaccine strains against genetically related local strains in the study area.

Emergency vaccination of cattle against lumpy skin disease: Evaluation of safety, efficacy, and potency of MEVAC® LSD vaccine containing Neethling strain

Lumpy skin disease (LSD) is an emerging disease of cattle causing significantly high economic losses. Control of LSD depends on the use of homologous attenuated LSD virus strains isolated originally from South Africa (the Neethling strain). The virus belongs to the genus Capripoxvirus, which includes sheep pox virus and goat pox virus. The present study was conducted to evaluate the safety and efficacy of a new live attenuated LSD vaccine produced by Middle East for Vaccines (MEVAC®) based on the Neethling strain. Tests were performed both in Egypt and Vietnam. Safety was evaluated by inoculation of five cattle with 10 times the recommended dose and observation of the animals for 14 days. Immunogenicity was tested at different periods post-vaccination (PV) in animals receiving the recommended doses of the vaccine using ELISA and virus neutralization test. Five cows were used to determine the protection index (PI) and non-vaccinated control cattle were included. Three calves were challenged by intradermal inoculation of the wild virus (5 × 105 TCID50) 28 days PV. Field or mass vaccination experiments were conducted in Vietnam during national campaigns in the summer of 2021 with 4301 vaccinated animals closely monitored after vaccination. In the field, around 2% (80/4301) of the animals showed hyper-reactivity, and 0.6% (24/4301) showed small skin swellings that disappeared within few hours PV. Abortion was recorded in three animals (0.3% 3/867). Challenged animals were resistant to clinical disease and PI value was 3.5 log10. Meanwhile, antibody levels determined by the ELISA were inconsistent among animals and laboratories during the study period. Overall, the findings point to a new safe and effective LSD vaccine.

Histopathologic differences in granulomas of Mycobacterium bovis bacille Calmette Guérin (BCG) vaccinated and non-vaccinated cattle with bovine tuberculosis.

Mycobacterium bovis (M. bovis) is the zoonotic bacterium responsible for bovine tuberculosis. An attenuated form of M. bovis, Bacillus Calmette-Guerin (BCG), is a modified live vaccine known to provide variable protection in cattle and other species. Protection for this vaccine is defined as a reduction in disease severity rather than prevention of infection and is determined by evaluation of the characteristic lesion of tuberculosis: the granuloma. Despite its recognized ability to decrease disease severity, the mechanism by which BCG imparts protection remains poorly understood. Understanding the histopathologic differences between granulomas which form in BCG vaccinates compared to non-vaccinates may help identify how BCG imparts protection and lead to an improved vaccine. Utilizing special stains and image analysis software, we examined 88 lymph nodes obtained from BGC-vaccinated and non-vaccinated animals experimentally infected with M. bovis. We evaluated the number of granulomas, their size, severity (grade), density of multinucleated giant cells (MNGC), and the amounts of necrosis, mineralization, and fibrosis. BCG vaccinates had fewer granulomas overall and smaller high-grade granulomas with less necrosis than non-vaccinates. The relative numbers of high- and low- grade lesions were similar as were the amounts of mineralization and the density of MNGC. The amount of fibrosis was higher in low-grade granulomas from vaccinates compared to non-vaccinates. Collectively, these findings suggest that BCG vaccination reduces bacterial establishment, resulting in the formation of fewer granulomas. In granulomas that form, BCG has a protective effect by containing their size, reducing the relative amount of necrosis, and increasing fibrosis in low-grade lesions. Vaccination did not affect the amount of mineralization or density of MNGC.

Lumpy Skin Virus; Herpesviridae Inevitable Synergism

Background: Lumpy skin virus (spp. Capripox) causes huge economic losses in farm animals. Herpesviridae spp. always showing synergistic role and worsen the disease symptoms. Negative staining of Transmission Electron Microscope techniques used in diagnosis to confirm the results for avoiding differential diagnosis doubts. Materials and Methods: Samples of Cutaneous crusts collected from infected cattle were tested by TEM and PCR (Conventional Polymerase Chain Reaction) then sequenced by ORF103 gene. Results: My study investigated LSD outbreak of non-vaccinated cattle. The confirmed diagnosis was outbreak of infection by Lumpy skin disease virus isolate Evros / GR/15 and 99% identity. A comparison of the gene sequence of the vaccine against the virus showed significant divergence between them. Electron microscopy reveals Lumpy skin viruses in variable functional forms. Herpes viruses were seen in close contact with the clusters of capripox virions which indicating the active co-infection. As a result, confections in same affected animals with the capripoxvirus spp. resulting in the appearance of the classical skin lesions of this disease (lumpy skin). Conclusions: LSD virus of cattle showed virulent nature in natural outbreak. However, the herpes viruses invade infected tissues and propagate inside cells of lumps that revealed its opportunistic behavior. Consequently; Antivirals against Herpesviridae would theoretically relief lumpy skin disease symptoms and help in control efforts.

Characterization of the duration of immunity of Brucella abortus strain RB51 vaccination in cattle after experimental challenge

Fifty-two, Hereford heifers were obtained from brucellosis-free herds and randomly assigned to Brucella abortus strain RB51 (RB51) vaccination (n = 32) or control (n = 20) treatments. Vaccinates received 1010 colony-forming units (CFU) of a commercial lyophilized RB51 vaccine. Immunologic responses after inoculation demonstrated significantly greater (P < 0.05) antibody, interferon-γ responses, and proliferative responses to RB51 antigens in cattle vaccinated with RB51 as compared to controls. A subgroup of control and vaccinated cattle were experimentally challenged at approximately 4, 5, and 6 years after inoculation with 107 CFU of B. abortus strain 2308 at 170–180 days gestation. After experimental challenge, 6 of 14 (43 %) control animals aborted at a higher rate (P < 0.05) when compared to RB51 vaccinates in years 4 and 5, but not year 6 (0 %, 10 %, and 50 %, respectively). When comparing recovery of Brucella from all tissues except head lymph nodes draining the site of challenge, RB51 vaccinates had reduced infection rates (P < 0.05) after experimental challenge at 4 years (14 %), but not at 5 or 6 years (78 % and 67 %, respectively) when compared to non-vaccinated cattle (93 %). Our data suggests that calfhood vaccination with RB51 does not induce lifelong immunity and suggests implementation of booster vaccination by 4–5 years of age should be utilized in endemic areas to maintain high levels of protection.

Targeted mutagenesis in Anaplasma marginale to define virulence and vaccine development against bovine anaplasmosis.

Tick-borne Anaplasma species are obligate, intracellular, bacterial pathogens that cause important diseases globally in people, agricultural animals, and dogs. Targeted mutagenesis methods are yet to be developed to define genes essential for these pathogens. In addition, vaccines conferring protection against diseases caused by Anaplasma species are not available. Here, we describe a targeted mutagenesis method for deletion of the phage head-to-tail connector protein (phtcp) gene in Anaplasma marginale. The mutant did not cause disease and exhibited attenuated growth in its natural host (cattle). We then assessed its ability to confer protection against wild-type A. marginale infection challenge. Additionally, we compared vaccine protection with the mutant to that of whole cell A. marginale inactivated antigens as a vaccine (WCAV) candidate. Upon infection challenge, non-vaccinated control cattle developed severe disease, with an average 57% drop in packed cell volume (PCV) between days 26–31 post infection, an 11% peak in erythrocytic infection, and apparent anisocytosis. Conversely, following challenge, all animals receiving the live mutant did not develop clinical signs or anemia, or erythrocyte infection. In contrast, the WCAV vaccinees developed similar disease as the non-vaccinees following A. marginale infection, though the peak erythrocyte infection reduced to 6% and the PCV dropped 43%. This is the first study describing targeted mutagenesis and its application in determining in vivo virulence and vaccine development for an Anaplasma species pathogen. This study will pave the way for similar research in related Anaplasma pathogens impacting multiple hosts.

Genotyping of Theileria parva populations in vaccinated and non-vaccinated cattle in Malawi.

Theileria parva is an apicomplexan protozoan parasite that causes bovine theileriosis (East Coast Fever; ECF) in central, eastern and southern Africa. In Malawi, ECF is endemic in the northern and central regions where it has negatively affected the development of dairy industry. Despite its endemic status the genetic population structure of T. parva in Malawi is currently unknown. To obtain an understanding of T. parva in Malawi, we performed population genetics analysis of T. parva populations in cattle vaccinated with the Muguga cocktail live vaccine and non-vaccinated cattle using mini- and microsatellite markers covering all the four T. parva chromosomes. The T. parva Muguga strain was included in this study as a reference strain. Linkage disequilibrium was observed when all samples were treated as a single population. There was sub-structuring among the samples as shown by the principal coordinate analysis. Majority of the samples clustered with the T. parva Muguga reference strain suggesting that the isolates in Malawi are closely related to the vaccine component, which support the current use of Muguga cocktail vaccine to control ECF. The clustering of samples from non-endemic southern region with those from endemic central region suggests expansion of the distribution of T. parva in Malawi.

Infectious Bovine Rhinotracheitis Control Program in Slovakia.

As for other European countries, IBR is a significant cause of financial losses in cattle in Slovakia. The State Veterinary and Food Administration of the Slovak Republic prepared a voluntary IBR control program for cattle farms in 1995, which was implemented in 1996. In subsequent years, 48-119 farms/year enrolled in the voluntary IBR control program. Since the end of 2006, the IBR control program became compulsory by law for all cattle farms in Slovakia. Serology was used to identify infected animals using a conventional ELISA amongst non-vaccinated cattle and a gE specific ELISA in cattle vaccinated with marker vaccine. Eradication is based on culling when the serological prevalence of IBR in a herd is below 15%. When the prevalence is higher than 15%, the culling is combined with the application of a marker vaccine. A radical method where all animals are slaughtered is used with the agreement of the farmer when appropriate, especially for very small herds. Depending upon the selected eradication method, the antibody positive cattle can be gradually replaced in the herds to eliminate financial losses due to the disease. The movement of cattle is under strict control requiring a health certificate issued by the state veterinary authority and the movement must be recorded in the central livestock registry. The next step for herds is monitoring to achieve official IBR-free status. Based on the official figures from The State Veterinary and Food Administration, 60.2% herds were free of IBR in Slovakia in 2020.

Repeated Oral Vaccination of Cattle with Shiga Toxin-Negative Escherichia coli O157:H7 Reduces Carriage of Wild-Type E. coli O157:H7 after Challenge.

Subcutaneous vaccination of cattle for enterohemorrhagic Escherichia coli O157:H7 reduces the magnitude and duration of fecal shedding, but the often-required, repeated cattle restraint can increase costs, deterring adoption by producers. In contrast, live oral vaccines may be repeatedly administered in feed, without animal restraint. We investigated whether oral immunization with live stx-negative LEE+E. coli O157:H7 reduced rectoanal junction (RAJ) colonization by wild-type (WT) E. coli O157:H7 strains after challenge. Two groups of cattle were orally dosed twice weekly for 6 weeks with 3 × 109 CFU of a pool of three stx-negative LEE+E. coli O157:H7 strains (vaccine group) or three stx-negative LEE- non-O157:H7 E. coli strains (control group). Three weeks following the final oral dose, animals in both groups were orally challenged with a cocktail of four stx+ LEE+E. coli O157:H7 WT strains. Subsequently, WT strains at the RAJ were enumerated weekly for 4 weeks. Serum antibodies against type III secretion protein (TTSP), the translocated intimin receptor (Tir), and EspA were determined by enzyme-linked immunosorbent assay (ELISA) at day 0 (preimmunization), day 61 (postimmunization, prechallenge), and day 89 (postchallenge). Vaccine group cattle had lower numbers of WT strains at the RAJ than control group cattle on postchallenge days 3 and 7 (P ≤ 0.05). Also, vaccine group cattle shed WT strains for a shorter duration than control group cattle. All cattle seroconverted to TTSP, Tir, and EspA, either following immunization (vaccine group) or following challenge (control group). Increased antibody titers against Tir and TTSP postimmunization were associated with decreased numbers of WT E. coli O157:H7 organisms at the RAJ.IMPORTANCE The bacterium E. coli O157:H7 causes foodborne disease in humans that can lead to bloody diarrhea, kidney failure, vascular damage, and death. Healthy cattle are the main source of this human pathogen. Reducing E. coli O157:H7 in cattle will reduce human disease. Using a randomized comparison, a bovine vaccine to reduce carriage of the human pathogen was tested. A detoxified E. coli O157:H7 strain, missing genes that cause disease, was fed to cattle as an oral vaccine to reduce carriage of pathogenic E. coli O157:H7. After vaccination, the cattle were challenged with disease-causing E. coli O157:H7. The vaccinated cattle had decreased E. coli O157:H7 during the first 7 days postchallenge and shed the bacteria for a shorter duration than the nonvaccinated control cattle. The results support optimization of the approach to cattle vaccination that would reduce human disease.

Serological prevalence of bovine viral diarrhoea (BVD-1) in non-vaccinated dairy cattle in the municipality of Realeza-Paraná

Bovine viral diarrhoea (BVD) is an infectious and contagious disease affecting cattle that is responsible for causing a wide range of clinical manifestations ranging from inapparent or subclinical infections to an acute and sometimes fatal disease known as mucosal disease. The agent that causes BVD is an RNA virus of the genus Pestivirus and family Flaviridae. BVD is transmitted in two different ways: horizontal, by secretions, and vertically in pregnant cows, where the cow transmits the virus to the foetus. The clinical signs depend on the affected animal, its immunological capacity, and in the case of pregnant females, the gestation phase. A gestational infection can result in several changes, such as congenital anomalies, abortion, or even the birth of so-called persistently infected (PI) animals, which are difficult to detect and have a very important epidemiological role within the herd. The southwest region of Paraná has the largest dairy basin in the state of Paraná and is predominantly composed of family farmers, many of whom adopt measures that increase the health risk of their herd. The objective of this study was to delineate the serological prevalence of non-vaccinated dairy cattle in the municipality of Royalty-PR in relation to the BVD-1 virus, as well as to evaluate the odds ratios, relative risk and risk attributable to the independent variables of breed, age and the community under study. To that end, 317 blood serum samples from non-vaccinated cows from 18 different farms, with various breeds and ages, were evaluated by virus neutralization for the detection of antibodies specific to BVD-1. The results showed that 17.03% of the animals (54/317) had positive BVD-1 serology, and 82.33% (15/18) of the farms had at least one positive animal. Animals of the Jersey breed and the Barra do Sarandi Line community had the highest epidemiological risks, with a strong association with BVD-1 infection.

Into the Deep (Sequence) of the Foot-and-Mouth Disease Virus Gene Pool: Bottlenecks and Adaptation during Infection in Naïve and Vaccinated Cattle.

Foot-and-mouth disease virus (FMDV) infects hosts as a population of closely related viruses referred to as a quasispecies. The behavior of this quasispecies has not been described in detail in natural host species. In this study, virus samples collected from vaccinated and non-vaccinated cattle up to 35 days post-experimental infection with FMDV A24-Cruzeiro were analyzed by deep-sequencing. Vaccination induced significant differences compared to viruses from non-vaccinated cattle in substitution rates, entropy, and evidence for adaptation. Genomic variation detected during early infection reflected the diversity inherited from the source virus (inoculum), whereas by 12 days post infection, dominant viruses were defined by newly acquired mutations. Mutations conferring recognized fitness gain occurred and were associated with selective sweeps. Persistent infections always included multiple FMDV subpopulations, suggesting distinct foci of infection within the nasopharyngeal mucosa. Subclinical infection in vaccinated cattle included very early bottlenecks associated with reduced diversity within virus populations. Viruses from both animal cohorts contained putative antigenic escape mutations. However, these mutations occurred during later stages of infection, at which time transmission is less likely to occur. This study improves upon previously published work by analyzing deep sequences of samples, allowing for detailed characterization of FMDV populations over time within multiple hosts.

Tubulin vaccinated Ankole cattle develop less severe lesions than the non-vaccinated cattle when experimentally infected with Trypanosoma brucei brucei

Tubulin vaccinated Ankole cattle develop less severe lesions than the non-vaccinated cattle when experimentally infected with Trypanosoma brucei brucei

Reduction of Milk Contamination with Aflatoxin-M1 through Vaccination of Dairy Cattle with Aflatoxin-B1 Vaccine

Aflatoxin M1 is one of mycotoxin derivatives, which is secreted in milk of dairy cattle fed on feed contaminated with Aflatoxin-B1 (AFB1). The current study was designed to prepare a vaccine against AFB1and to evaluate its efficacy in reducing or preventing secretion of AFM1 in milk. Aflatoxin-B1 was prepared, purified and transformed into oxime, then it was fixed on bovine serum albumins. The AFB1-BSA conjugate was adjuvanted with Gold Nano particles then Montanide ISA 206. The prepared vaccine was used for immunization of rabbits by S/c routes as 100 µg/dose and dairy cattle by I/M routes as 500 µg/dose. The vaccinated animals were boosted at 3 weeks post primary immunization. Serum samples were collected and examined for the anti-AFB1 using AGPT. A mean titer of 15.2 AGPU/ml was detected at 2 weeks post primary vaccination then significantly increased till reached to 76.8 AGPU/ml at 6 weeks post Booster vaccination. All vaccinated rabbits were challenged with dose of 0.3 mg AFB1 toxin/Kg. The vaccinated rabbit showed 100% protection and no AFB1 toxin residue was detected in their livers. Milk samples were collected from non-vaccinated and AFB1-immunized dairy cattle then examined with ELISA for quantitation of AFM1 residues before and after vaccination. The results showed that the prepared AFB1 vaccine was safe, potent and able to reduce AFM1 release in milk of vaccinated heifers by 70%. So the vaccination of lactating animals with the AFB1vaccine might represent a valid tool for the prevention of AFM1 contamination of milk and dairy products.

Seroprevalence and risk factors of bovine respiratory syncytial virus in cattle in the Nineveh Governorate, Iraq.

Background and Aim:Bovine respiratory syncytial virus (BRSV) is one of the main causes of severe pneumonia, interstitial edema, and emphysema in cattle. The current study investigated the prevalence and risk factors of BRSV in cattle in the Nineveh Province, Iraq.Materials and Methods:Between September 2017 and September 2018, 450 serum samples were collected from non-vaccinated cattle of different ages and breeds for BRSV testing. The epidemiological information of the animals was recorded. The prevalence of the disease was determined using an indirect enzyme-linked immunosorbent assay kit.Results:The prevalence of BRSV was 83.11%, and it was significantly (p<0.05) higher in cattle aged greater than 7 months-1.5 years than in older animals; in imported cattle than in Native animals; and in animals originating from large herds (100 animals) than in those from smaller herds (40 animals). There was no significant difference between BRSV prevalence in male and female animals. When samples from different regions of the Nineveh Governorate were compared, the northern region was associated with the highest prevalence of the disease. Samples harvested in the winter displayed the highest BRSV titer, compared to those collected during the other seasons.Conclusion:BRSV is prevalent in cattle from the Nineveh Governorate. Risk factors such as animal age, origin, herd size, and the herd’s geographical location are associated with an increased prevalence of the disease in this region. Routine vaccination programs should be adopted to reduce the prevalence of BRSV.