Vaccination Of Cattle Research Articles

Vaccination of cattle in the system of antiepizootic measures in Buryatia

On the territory of the Republic of Buryatia, six nosological forms of infectious diseases have epizootic significance among cattle. The most widespread are leptospirosis, rabies, and isolated cases of pasteurellosis. Natural foci of rabies were formed, confined to the environmental conditions of the neighboring territories of Mongolia and the TRANS-Baikal territory. Epizootic process tends to polyhostal manifestation with the threat of expanding the focus and complicating the epidemic situation in the entire region of Siberia and the Far East. In 2018 169 heads of cattle were identified with a positive reaction to leptospirosis in 13 administrative districts. Preventive immunization of animals with the control of immunity tension in areas with a high risk of introduction of infectious diseases is the basis for maintaining epizootic well-being throughout the region.

Recombinant bovine IL17A acts as an adjuvant for bovine herpesvirus vaccine

The Bovine herpes virus type 5 glycoprotein D (gD) is essential for viral penetration into host permissive cells. The Herpes virus gD glycoprotein has been used for bovine immunization, being efficient in reduction of viral replication, shedding and clinical signs, however sterilizing immunity is still not achieved. Recombinant subunit vaccines are, in general, poorly immunogenic requiring additional adjuvant components. Interleukin 17A (IL17A) is a pro-inflammatory cytokine produced by T helper 17 cells that mediate mucosal immunity. IL17 production during vaccine-induced immunity is a requirement for mucosal protection to several agents. In this study, we investigated the potential of a recombinant IL17A to act as an adjuvant for a recombinant BoHV-5 glycoprotein D vaccine in cattle. Three cattle groups were divided as: group 1) rgD5 + alumen + rIL-17A; 2) rgD5 + alumen; and 3) PBS + alumen. The cattle (3 per group) received two doses of their respective vaccines at an interval of 21 days. The group that received rIL17 in its vaccine formulation at the 7th day after the prime immunization had significant higher levels of specific rgD-IgG than the alumen group. Addition of rIL17 also led to a significant fold increase in specific anti-rgD IgG and neutralizing antibodies to the virus, respectively, when compared with the alumen group. Cells stimulated with rIL17A responded with IL17 transcription, as well IL2, IL4, IL10, IL15, Bcl6 and CXCR5. Our findings suggest that the rIL17A has adjuvant potential for use in vaccines against BoHV-5 as well as potentially other pathogens of cattle.

Paratuberculosis vaccination specific and non-specific effects on cattle lifespan

Records of cattle vaccination against paratuberculosis (PTB) have been analyzed to determine whether or not non-specific effect (NSE) on overall mortality similar to that observed in BCG vaccinated humans occurs in animals. The results of a previously reported slaughterhouse study on PTB prevalence were used as a reference on the age incidence of advanced patent (clinical) epidemio-pathogenic forms. In the proper vaccine study, cows in 30 cattle farms in the Basque Country, Spain were followed-up for between 1 and 13 years. Vaccinated groups were composed by 1008 (592 right-censored) animals younger than 3 months treated as calves and by 3761 (3160 right-censored) vaccinated at any older age. Controls were 339 (157 right-censored) and 4592 (2213 right-censored) age matched animals, respectively. Individual last year presence in the annual testing was considered age at culling or death. A survival analysis was carried out according age at vaccination of vaccinated versus non-vaccinated animals. PTB age incidence in the slaughterhouse study was subtracted from the difference between vaccinated and non-vaccinated animals at the same age in order to estimate PTB-specific and non-specific effects. The maximum difference was observed at the 2–3 years interval with a 33.9% mortality reduction in the calf vaccinated group. This corresponded also with the maximum NSE that was 24.5% for a PTB incidence of 9.5%. Overall, vaccination afforded to calves a 26.5% yearly mortality protection, split between 11.1% PTB-specific and 15.4% NSE. These results support a NSE on total mortality associated with PTB vaccination that appeared to persist for up to 6–7 years. This confirms for the first time in an animal field study the innate immune system memory predicted by the recently proposed trained immunity theory. Contrasting the literature, no deleterious effects of killed vaccines on females were observed. Mortality reduction would offset vaccination costs and could improve livestock systems efficiency and potentially reduce antibiotic use.Clinical trial registered with Spanish Agency for Drugs and Sanitary products (AEMPS) as 11/012/ECV.

Investigation of an anthrax outbreak in Makoni District, Zimbabwe

BackgroundAnthrax continues to be a disease of public health importance in Zimbabwe, with sporadic outbreaks reported annually in many parts of the country. A human anthrax outbreak occurred in wards 22 and 23 of Makoni District from mid-June 2013 to end of January 2014, following cattle deaths in the wards. Laboratory tests confirmed anthrax as the cause for the cattle deaths. This study investigated the clinical characteristics, distribution of cases (places, person and time) and risk factors for contracting the anthrax disease. We also assessed the environment, district preparedness and response, and outbreak prevention and control measures.MethodsWe conducted an outbreak investigation using a mixed-methods design. A 1:1 case-control study was used to assess risk factors for contracting anthrax. The controls were frequency matched to cases by sex. Data were collected using a structured interviewer-administered questionnaire. Environmental assessment, district preparedness and response, and outbreak prevention and control measures were assessed using a checklist, observations, and key informant interviews. Multivariable unconditional logic regression analysis was performed to identify independent risk factors associated with contracting anthrax.ResultsWe interviewed 37 of the 64 cases, along with 37 controls. All the cases had cutaneous anthrax, with the hand being the most common site of the eschar (43%). Most of the cases (89%) were managed according to the national guidelines. Multivariable analysis demonstrated that meat sourced from other villages [vs butchery, OR = 15.21, 95% CI (2.32–99.81)], skinning [OR = 4.32, 95% CI (1.25–14.94)], and belonging to religions that permit eating meat from cattle killed due to unknown causes or butchered after unobserved death [OR = 6.12, 95% CI (1.28–29.37)] were associated with contracting anthrax. The poor availability of resources in the district caused a delayed response to the outbreak.ConclusionThe described anthrax outbreak was caused due to contact with infected cattle meat. Although the outbreak was eventually controlled through cattle vaccination and health education and awareness campaigns, the response of the district office was initially delayed and insufficient. The district should strengthen its emergency preparedness and response capacity, revive zoonotic committees, conduct awareness campaigns and improve surveillance, especially during outbreak seasons.

Still 'dairy farm fever'? A Bayesian model for leptospirosis notification data in New Zealand.

Routinely collected public health surveillance data are often partially complete, yet remain a useful source by which to monitor incidence and track progress during disease intervention. In the 1970s, leptospirosis in New Zealand (NZ) was known as ‘dairy farm fever’ and the disease was frequently associated with serovars Hardjo and Pomona. To reduce infection, interventions such as vaccination of dairy cattle with these two serovars was implemented. These interventions have been associated with significant reduction in leptospirosis incidence, however, livestock-based occupations continue to predominate notifications. In recent years, diagnosis is increasingly made by nucleic acid detection which currently does not provide serovar information. Serovar information can assist in linking the recognized maintenance host, such as livestock and wildlife, to infecting serovars in human cases which can feed back into the design of intervention strategies. In this study, confirmed and probable leptospirosis notification data from 1 January 1999 to 31 December 2016 were used to build a model to impute the number of cases from different occupational groups based on serovar and month of occurrence. We imputed missing occupation and serovar data within a Bayesian framework assuming a Poisson process for the occurrence of notified cases. The dataset contained 1430 notified cases, of which 927 had a specific occupation (181 dairy farmers, 45 dry stock farmers, 454 meatworkers, 247 other) while the remaining 503 had non-specified occupations. Of the 1430 cases, 1036 had specified serovars (231 Ballum, 460 Hardjo, 249 Pomona, 96 Tarassovi) while the remaining 394 had an unknown serovar. Thus, 47% (674/1430) of observations had both a serovar and a specific occupation. The results show that although all occupations have some degree of under-reporting, dry stock farmers were most strongly affected and were inferred to contribute as many cases as dairy farmers to the burden of disease, despite dairy farmer being recorded much more frequently. Rather than discard records with some missingness, we have illustrated how mathematical modelling can be used to leverage information from these partially complete cases. Our finding provides important evidence for reassessing the current minimal use of animal vaccinations in dry stock. Improving the capture of specific farming type in case report forms is an important next step.

Experimental Infection of Calves with Transfected Attenuated Babesia bovis Expressing the Rhipicephalus microplus Bm86 Antigen and eGFP Marker: Preliminary Studies towards a Dual Anti-Tick/Babesia Vaccine.

Bovine babesiosis, caused by Babesia bovis and B. bigemina, is a major tick-borne disease of cattle with global economic impact. The disease can be prevented using integrated control measures including attenuated Babesia vaccines, babesicidal drugs, and tick control approaches. Vaccination of cattle with the Rhipicephalus microplus Bm86-based recombinant vaccine reduces the fitness of R. microplus and R. annulatus, but several booster inoculations are required to maintain protection. Herein, we generated a stable transfected strain of B. bovis expressing an enhanced GFP (eGFP) and a chimeric version of Bm86 (B. bovis/Bm86/eGFP). The eGFP was expressed in the parasite cytoplasm, whereas Bm86 was displayed on the surface of merozoites. Three splenectomized calves experimentally infected with B. bovis/Bm86/eGFP showed mild signs of acute disease and developed long-lasting antibody responses to B. bovis and native Bm86. No evidence of sequestration of parasites in the cerebral capillaries was found upon postmortem analysis, confirming attenuation of the strain. This is the first report of transfected B. bovis expressing the tick antigen Bm86 on the merozoite surface that elicits an antibody response to native Bm86. These results represent a proof of concept for a novel live, attenuated, tagged dual-vaccine approach to attempt simultaneous control of babesiosis and tick infestation.

Current status of adult cattle vaccination with Strain 19 in Florida

Vaccination of adult cattle with 1/25th of the standard dose of strain 19 reduced the number of cattle removed from 110 herds in one year by 85% in 85 dairy herds and by 90% in 25 beef herds. This dose also minimized the effects of false positive reactions to serological tests. Complement fixation was found to be superior to other tests for diagnosing infection in vaccinated cattle.

A single vaccination with four-segmented Rift Valley fever virus prevents vertical transmission of the wild-type virus in pregnant ewes

Rift Valley fever virus (RVFV) is a mosquito-transmitted bunyavirus that causes severe outbreaks among wild and domesticated ruminants, of which sheep are the most susceptible. Outbreaks are characterised by high mortality rates among new-born lambs and abortion storms, in which all pregnant ewes in a flock may abort their foetuses. In endemic areas, Rift Valley fever (RVF) can be controlled by vaccination with either inactivated or live-attenuated vaccines. Inactivated vaccines are safe for animals during all physiological stages, including pregnancy. However, optimal efficacy of these vaccines depends on multiple vaccinations and yearly re-vaccination. Live-attenuated vaccines are generally highly efficacious after a single vaccination, but currently available live-attenuated vaccines may transmit to the ovine foetus, resulting in stillbirths, congenital malformations or abortion. We have previously reported the development of a novel live-attenuated RVFV vaccine, named RVFV-4s. This vaccine virus was created by splitting the M genome segment and deleting the major virulence determinant NSs, and was shown to be safe even for the most susceptible species, including pregnant ewes. The demonstrated efficacy and safety profile suggests that RVFV-4s holds promise for veterinary and human application. The RVFV-4s vaccine for veterinary application, here referred to as vRVFV-4s, was shown to provide complete protection after a single vaccination of lambs, goats and cattle. In this work, we evaluated the efficacy of the vRVFV-4s vaccine in pregnant ewes. Anticipating on the extremely high susceptibility of pregnant ewes for RVFV, both a single vaccination and double vaccination were evaluated in two independent experiments. The combined results suggest that a single vaccination with vRVFV-4s is sufficient to protect pregnant ewes and to prevent transmission to the ovine foetus.

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.

Optimal control and cost-effectiveness analysis of taeniasis and cysticercosis in humans, pigs and cattle

Taeniasis and cysticercosis are neglected food-borne diseases that pose challenge to food safety, human health and livelihood of rural livestock farmers. In this paper, an optimal control problem for the dynamics and control of taeniasis and cysticercosis in humans, pigs and cattle with its cost-effectiveness analysis is presented and analysed to determine the optimal and cost-effective strategy for disease control. A combination of two or more time dependent controls involving vaccination of pigs and cattle, meat inspection, environmental hygiene and sanitation, and the treatment of humans who are infected with taeniasis is carried out to study their impacts on disease control. The Pontryagin’s maximum principle is adopted to find the necessary conditions for existence of the optimal controls. The Runge Kutta order four forward-backward sweep method is implemented to solve the optimal control problem. The incremental cost-effectiveness ratio (ICER) is applied to determine the most cost-effective strategy for disease control. The optimal control results indicate that the strategy which focus on the combination of all interventions or that exclude vaccination of pigs and cattle is the most effective optimal control strategy in disease control. However, cost-effectiveness analysis results show that a strategy which excludes vaccination of pigs and cattle is the most cost-effective strategy for disease control. Based on these results, we recommend that interventions which focus on meat inspection, treatment of humans who are infected with taeniasis and improvement in hygiene and sanitation should be considered to control the transmission of taeniasis and cysticercosis in humans, pigs and cattle at a minimal cost.

In search of a combined brucellosis and tuberculosis vaccine for cattle

Bovine brucellosis is caused by Brucella abortus. The bacterial pathogen causes economic losses because it induces abortion in cattle. Vaccination of calves with live B. abortus strain 19 induces a certain level of protection but induces persistent antibodies against cell envelope lipopolysaccharide that make it difficult to Distinguish Infected from Vaccinated Animals (DIVA). Live vaccine B. abortus strain RB51 was developed to eliminate such interfering antibodies and therefore, facilitate the differentiation of infected from vaccinated animals and help in the eradication of the disease. Vaccination with strain RB51 induces levels of protection similar to strain 19 but neither of the two vaccines give complete protection. We have been working to enhance protection induced by strain RB51 vaccine. Protective Brucella antigens can be over-expressed in strain RB51 by introducing a plasmid containing the leuB gene and the genes encoding such antigens. To avoid the expression of antibiotic resistance genes, we produced a leuB deficient strain RB51 and introduced a plasmid containing the leuB gene and the genes to be over-expressed. This new strain maintains the plasmid and has induced significantly high protection levels in mice. In addition, it allowed the construction of an RB51 vaccine strain able to express Mycobacterium bovis protective antigens so that the vaccine could protect against brucellosis and tuberculosis simultaneously.

Економічні аспекти превенції сказу тварин

Економічні аспекти превенції сказу тварин

A novel MHC-II targeted BVDV subunit vaccine induces a neutralizing immunological response in guinea pigs and cattle.

Bovine viral diarrhoea virus (BVDV) is a major cause of economic loss in the cattle industry, worldwide. Infection results in reduced productive performance, growth retardation, reduced milk production and increased susceptibility to other diseases leading to early culling of animals. There are two primary methods used to control the spread of BVDV: the elimination of persistently infected (PI) animals and vaccination. Currently, modified live or inactivated vaccines are used in BVDV vaccination programmes, but there are safety risks or insufficient protection, respectively, with these vaccines. Here, we report the development and efficacy of the first targeted subunit vaccine against BVDV. The core of the vaccine is the fusion of the BVDV structural protein, E2, to a single-chain antibody, APCH, together termed, APCH-E2. The APCH antibody targets the E2 antigen to the major histocompatibility type II molecule (MHC-II) present on antigen-presenting cells. Industrial production of the vaccine is carried out using the baculovirus expression vector system (BEVS) using single-use manufacturing technologies. This new subunit vaccine induces strong BVDV-specific neutralizing antibodies in guinea pigs and cattle. Importantly, in cattle with low levels of natural BVDV-specific neutralizing antibodies, the vaccine induced strong neutralizing antibody levels to above the protective threshold, as determined by a competition ELISA. The APCH-E2 vaccine induced a rapid and sustained neutralizing antibody response compared with a conventional vaccine in cattle.

Incidences of Calf Diarrhea and the Associated Risk Factors in Ivory Coast (2015-2017)

Diarrhea is the most important disease of neonatal calves, and it results in the greatest economic losses. A longitudinal observational study was conducted from September 2015 to October 2017. This study proposes to investigate the incidence of diarrhea in calves and their mortality rate so as to identify potential risk factors related to the occurrence of calf diarrhea on 372 farms in the regions of Abidjan, Bouake, Bondoukou, and Korhogo in Ivory Coast. Information on potential risk factors was collected based on personal observations from regular visits to the farms and from a survey conducted during the period of the study. A total of 2020 calves under the age of three months were selected. Only 347 (17.17%) of the 2020 calves showed signs of diarrhea. The overall mortality rate was 0.39%. Based on the survey, colostrum feeding, the calf’s age and sex, calf housing, seasonal variation, the calving period, environment conditions, the ignorance of herdsmen, and management systems were found to be the major risk factors for gastroenteritis in calves. Calves reared in an extensive system were less susceptible to neonatal diarrhea. The calf health and management issues found in this study can be resolved by creating awareness among farm owners and implementing better calf management practices and cattle vaccination programs.

Field, serological and biochemical evaluation of Bovine Ephemeral Fever and Rabies vaccines in cattle and baffaloes

Family Rhabdoviride contains 2 genera Ephemerovirus and Lyssavirus which contain viruses responsible for two destructive diseases Bovine Ephemeral Fever (BEF) and rabies, respectively. Both diseases cause direct and indirect economic losses related to deaths, abortions, cost of treatment and prevention, zoonotic impact and restriction of animal movement. The main objective of this study is to evaluate the immune responses of cattle and buffalo vaccinated with BEF and rabies vaccines when administered separately in comparison with co vaccination. Serum samples were collected from 16 cattle and buffaloes (eight of each) then subjected to serum neutralization test SNT, serum biochemical, liver and kidney function for comparison according to the vaccinated groups. Each animal species divided into 4 groups (2 animals /group) group 1 was vaccinated by 2 doses of attenuated BEF vaccine inactivated at time of use with 2 weeks in between, group 2 was vaccinated by 1 dose of inactivated rabies vaccine, group 3 was vaccinated by rabies vaccine simultaneous with 1st dose of BEF vaccine and boostering dose of BEF vaccine after 2 weeks, group 4 not vaccinated and let to be control group. The results showed that both live attenuated BEF and inactivated cell culture rabies vaccines are safe because they didn’t harmful effect on liver and kidney functions, they are immunogenic as they lead to significant increase in total serum protein due to increase in globulin. Co-vaccination of both vaccines together has higher levels of specific antibodies against both BEF and rabies in all vaccinated animals.

Isolation of brucella strains in cattle from sedentary and nomadic communities and its public health implication

Background: Brucellosis is a highly infectious disease caused by bacteria of the genus brucella affecting animals leading to high economic loss and an impediment to livestock exportation. It also infects man with serious public health consequences. The disease is one of the world's most important neglected tropical zoonoses. Brucellosis is considered endemic in Nigeria and current information on isolation in sedentary and nomadic cattle is required. We carried out an active surveillance in sedentary cattle in Kachia Grazing Reserve (KGR), Kaduna State and in nomadic communities on the Jos Plateau to isolate brucella organisms and carry out phenotypic and molecular characterization of the isolates to species level. Methods & Materials: A total of 63 vaginal swabs, 36 milk samples, and 2 hygroma fluids were collected from cattle in KGR while 70 vaginal swabs, 50 milk samples and 2 hygroma fluids were collected from cattle on the Jos Plateau using a purposive sampling technique. Only animals that had history of abortion or infertility were sampled. They were cultured on serum dextrose agar with addition of antibiotic supplement (Oxoid) and incubated at 37 °C for 3 days in 5% CO2 atmosphere. Brucella strains isolated were biotyped along with eight archived isolates according to classical Brucella biotyping method. Isolates were further subjected to Bruce-ladder multiplex PCR according to established protocol. Results: Three and four B. abortus strains were isolated from KGR and Jos Plateau respectively. Biotyping revealed that all the 15 isolates were B. abortus biotype 3. Bruce-ladder multiplex PCR showed bands consistent with B. abortus. Conclusion: The study established the endemicity of brucellosis due to B. abortus biotype 3 in the two study areas. These findings have great veterinary and public health implications as healthy animals and the farmers are at high risk of infection due to contact with infected animals, consumption of raw milk and other products. Farmers were advised to boil their milk before consumption, isolate infected animals, maintain good level of hygiene and use protective wears in handling their animals as preventive measures. The study recommends vaccination of cattle against brucellosis in the areas.

PSIV-20 Evaluation of calf performance when cows grazing native rangeland are vaccinated for bovine viral diarrhea virus and infectious bovine rhinotracheitis using either a modified live or killed vaccine

Abstract Bovine viral diarrhea virus (BVDV) is a pathogen associated with gastrointestinal, respiratory, and reproductive diseases of cattle worldwide. Vaccination of cattle with antivirals have proven effective to reduce instances of BVDV. However, vaccination protocol adoption by producers and animal response to vaccination varies. The objective of this study was to determine if administration to the dam of a modified-live viral vaccine (MLV) or killed viral vaccine (KV) would impact the growth and rumen fermentation end products of the calf. The hypothesis for this study was that calves from dams vaccinated with MLV would have improved performance. Calves (n=20) born to dams that received either MLV or KV over the course of their lifetime, were housed on rangeland at the Corona Range and Livestock Research Center in Corona, NM. Cow ruminal contents were collected at birth. Both cow and calf ruminal contents were collected at 7, 35, 63, and 205 d of age. Cow body condition score did not differ between treatments (P > 0.05) (average KV = 4.3 + 0.8 and MLV = 4.3 + 0.8) at calving. Additionally, calf birth (P =0.66) weight and weaning weight (P > 0.05) did not differ between dam vaccine type. At days postpartum x vaccine type interaction was not observed for calf ruminal pH (P = 0.20) and volatile fatty acid concentrations (P > 0.28). However, calf ruminal pH increased with age (P < 0.0001). Butyrate concentrations were least at 7 days of age (P = 0.0069). Therefore, we reject our hypothesis; calves born from dams receiving MLV do not have improved performance when compared to KV counterparts. Results indicate birth weight, weaning weight, pre-weaned calves pH, and volatile fatty acid concentration, are not impacted by dam’s vaccination type. However, impacts on calf immunity have not been evaluated and require further research.

PSI-33 Evaluation of calf performance when cows grazing native rangeland are vaccinated for bovine viral diarrhea virus and infectious bovine rhinotracheitis using either a modified live or killed vaccine

Abstract Bovine viral diarrhea virus (BVDV) is a pathogen associated with gastrointestinal, respiratory, and reproductive diseases of cattle worldwide. Vaccination of cattle with antivirals have proven effective to reduce instances of BVDV. However, vaccination protocol adoption by producers and animal response to vaccination varies. The objective of this study was to determine if administration to the dam of a modified-live viral vaccine (MLV) or killed viral vaccine (KV) would impact the growth and rumen fermentation end products of the calf. The hypothesis for this study was that calves from dams vaccinated with MLV would have improved performance. Calves (n = 20) born to dams that received either MLV or KV over the course of their lifetime, were housed on rangeland at the Corona Range and Livestock Research Center in Corona, NM. Cow ruminal contents were collected at birth. Both cow and calf ruminal contents were collected at 7, 35, 63, and 205 d of age. Cow body condition score did not differ between treatments (P > 0.05) (average KV = 4.3 + 0.8 and MLV = 4.3 + 0.8) at calving. Additionally, calf birth (P =0.66) weight and weaning weight (P > 0.05) did not differ between dam vaccine type. At days postpartum x vaccine type interaction was not observed for calf ruminal pH (P = 0.20) and volatile fatty acid concentrations (P > 0.28). However, calf ruminal pH increased with age (P < 0.0001). Butyrate concentrations were least at 7 days of age (P = 0.0069). Therefore, we reject our hypothesis; calves born from dams receiving MLV do not have improved performance when compared to KV counterparts. Results indicate birth weight, weaning weight, pre-weaned calves pH, and volatile fatty acid concentration, are not impacted by dam’s vaccination type; however, impacts on calf immunity have not been evaluated and require further research.

An Improved DNA Vaccine Against Bovine Herpesvirus-1 Using CD40L and a Chemical Adjuvant Induces Specific Cytotoxicity in Mice.

Bovine herpesvirus-1 (BoHV-1) uses many mechanisms to elude the immune system; one of them is spreading intracellularly, even in the presence of specific antiviral antibodies. Cytotoxic T lymphocytes (CTLs) are necessary to eliminate the virus. The main preventive strategy is vaccination based on inactivated virus. These vaccines are poor inducers of cellular immune responses, and complicate serological diagnosis and determination of the real prevalence of infection. DNA vaccines are a good option because of the capacity of Differentiating Infected from Vaccinated Animals-(DIVA vaccine)-and may be the best way to induce cytotoxic responses. Although this type of vaccines leads to only weak "in vivo" expression and poor immune responses, incorporation of molecular and/or chemical adjuvants can improve the latter, both in magnitude and in direction. In this study, we have investigated the specific immune responses elicited in mice by DNA vaccines based on the BoHV-1 glycoprotein D (pCIgD) with and without two different adjuvants: a plasmid encoding for murine CD40L (pCD40L) or Montanide™ 1113101PR (101). Mice vaccinated with pCIgD+CD40L, pCIgD+101, and pCIgD+CD40L+101 developed significantly higher specific antibody titers against BoHV-1 than the pCIgD group (p < 0.01). The animals vaccinated with pCgD+pCD40L+101 raised significantly higher levels of IgG2a and IgG2b (p < 0.01 and p < 0.001, respectively) than mice vaccinated with pCIgD alone. On the contrary, when the activity of CTL against cells infected with BoHV-1 was measured, the vaccine pCgD+pCD40L+101 induced significantly higher levels of cytotoxicity activity (p < 0.001) than pCIgD alone. A significant increase in the CD4+ populations in the group receiving pCIgD+CD40L+101 in comparison with the pCIgD group was observed and, also, interferon gamma, interleukin (IL)-6, and IL-17A levels were higher. Considering the results obtained from this study for humoral and cellular responses in mice, the inclusion of pCD40L and 101 as adjuvants in a BoHV-1 DNA vaccine for cattle is highly recommendable.

Novel Foot-and-Mouth Disease Vaccine Platform: Formulations for Safe and DIVA-Compatible FMD Vaccines With Improved Potency.

Inactivated, wild-type foot-and-mouth disease virus (FMDV) vaccines are currently used to control FMD around the world. These traditional FMD vaccines are produced using large quantities of infectious, virulent, wild-type FMD viruses, with the associated risk of virus escape from manufacturing facilities or incomplete inactivation during the vaccine formulation process. While higher quality vaccines produced from wild-type FMDV are processed to reduce non-structural antigens, there is still a risk that small amounts of non-structural proteins may be present in the final product. A novel, antigenically marked FMD-LL3B3D vaccine platform under development by Zoetis, Inc. and the USDA-ARS, consists of a highly attenuated virus platform containing negative antigenic markers in the conserved non-structural proteins 3Dpol and 3B that render resultant vaccines fully DIVA compatible. This vaccine platform allows for the easy exchange of capsid coding sequences to create serotype-specific vaccines. Here we demonstrate the efficacy of the inactivated FMD-LL3B3D-A24 Cruzeiro vaccine in cattle against wild-type challenge with A24 Cruzerio. A proprietary adjuvant system was used to formulate the vaccines that conferred effective protection at low doses while maintaining the DIVA compatibility. In contrast to wild-type FMDV, the recombinant FMD-LL3B3D mutant viruses have been shown to induce no clinical signs of FMD and no shedding of virus in cattle or pigs when inoculated as a live virus. The FMD-LL3B3D vaccine platform, currently undergoing development in the US, provides opportunities for safer vaccine production with full DIVA compatibility in support of global FMDV control and eradication initiatives.