Source: MICHIGAN STATE UNIV submitted to NRP
IMPACT OF BOVINE LEUKEMIA VIRUS INFECTION ON DISEASE INCIDENCE AND SEVERITY IN DAIRY CATTLE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
AFRI COMPETITIVE GRANT
Reporting Frequency
Annual
Accession No.
1012337
Grant No.
2017-67015-26806
Cumulative Award Amt.
$494,000.00
Proposal No.
2016-09480
Multistate No.
(N/A)
Project Start Date
Jul 1, 2017
Project End Date
Jun 30, 2022
Grant Year
2017
Program Code
[A1221]- Animal Health and Production and Animal Products: Animal Health and Disease
Recipient Organization
MICHIGAN STATE UNIV
(N/A)
EAST LANSING,MI 48824
Performing Department
Large Animal Clinical Sciences
Non Technical Summary
Enzootic Bovine Leukosis is an incurable infectious disease of cattle caused by bovine leukemia virus (BLV). BLV-infected cows may have normal lymphocyte counts (aleukemic; AL) or elevated lymphocyte counts (persistent lymphocytosis; PL). For years, BLV was ignored in the U.S., and more than 40% of dairy cattle are now infected with BLV and over 80% of all dairies have infected cattle. Transmission of BLV to susceptible cows is thought to occur primarily by proviral-infected B lymphocytes, and experimental studies have demonstrated that PL cows are much more likely to transmit the disease when compared to AL cows. When the BLV prevalence was still relatively low in the 1960s and 1970s, the U.S. dairy industry decided that BLV control was not economically justifiable. Other nations had a different view and decided to control BLV for economic, public health and animal welfare reasons. Currently, 21 nations and Western Australia have successfully eradicated BLV from their cattle herds. BLV infection negatively affects milk production at the herd- and individual-cow levels, and BLV has also been shown to decrease cow longevity. Direct losses to the U.S. dairy industry and consumers were estimated to be in excess of $500M yearly. These productivity losses are most likely due to identified immunosuppressive effects of BLV, that decrease cows' ability to respond to vaccination and may increase their susceptibility to pathogens. The effects of BLV-induced immune system dysfunction with respect to disease susceptibility is largely undetermined. Very little information is available on how BLV status of dairy cows affect their ability to fight naturally occurring diseases as for example mastitis. Knowledge about BLV's impact on naturally occurring disease is crucial to attract producers to adapt control measures. In the proposed project, we will 1) determine the effect of BLV-status (negative, AL, and PL) on host biomarker responses to experimentally-induced coliform mastitis, and 2) determine the effect of BLV status on the risk of dairy cows developing naturally occurring clinical disease during an entire lactation period.
Animal Health Component
70%
Research Effort Categories
Basic
30%
Applied
70%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
3113410104010%
3113410109030%
3113410110010%
3113410117050%
Knowledge Area
311 - Animal Diseases;

Subject Of Investigation
3410 - Dairy cattle, live animal;

Field Of Science
1040 - Molecular biology; 1090 - Immunology; 1100 - Bacteriology; 1170 - Epidemiology;
Goals / Objectives
The long-term goal of our group is to improve sustainability of the U.S. dairy industry and U.S. food security by increasing production efficiency and providing dairy producers with scientifically-sound interventions to reduce the prevalence of BLV in their herds. The overall goal of this project is to determine the impact of BLV infection on cows' ability to mount an immune response to vaccination and naturally occurring diseases. To pursue this overall goal, we will address the following specific objectives: 1) determine the effect of BLV-status on host responses to experimentally induced coliform mastitis, and 2) determine the effect of BLV-status on the risk of cows developing naturally occurring infections during a lactation period. This project will, for the first time, determine the direct impact of cows' BLV status on clinical infectious diseases in dairy cattle. This knowledge will be integral to provide a more complete assessment of the economic impact of BLV on the U.S. dairy industry and to stress the threat of BLV to the sustainability of U.S. dairy farmers. We believe, that if we can show, that BLV infections attribute significantly to the clinical diseases that producers encounter on a daily basis, then they will be more likely to engage in control the disease.
Project Methods
Objective 1. Twenty-four healthy Holstein-Friesian dairy cows in their second week of lactation will be used for this block-randomized experimental study. The cows will be assembled into three treatment groups based on their BLV status; 8 BLV-negative, 8 AL cows and 8 PL cows. Each block will consist of one BLV-negative cow, one BLV cow and one PL cow. The cows will be in their second or third lactation. The block design will ensure that cows from each treatment group in a block will be exposed to the same environmental conditions. All 24 cows will be vaccinated with a commercial J5 bacterin at 7 and 8 months of pregnancy and within 48 hours after calving according to label directions. Cows will be dried off by abrupt cessation of milking, and all four quarters will be treated with an FDA approved antimicrobial infusion product (determined by the participating farms) approximately 60 days prior to expected calving. The coliform mastitis challenge will be performed approximately 2 weeks after parturition. Cows developing systemic clinical signs of acute coliform mastitis will be treated. Cows that are negative on the BLV ELISA and proviral load (PVL) qPCR will be considered BLV-negative. BLV-positive cows, will be animals positive on a serum-ELISA test and by qPCR. The aleukemic (AL) and persistent lymphocytosis (PL) statuses of cows will be determined using white blood cell counts. Cows that are BLV positive and have a lymphocyte count of less than 10,000 lymphocytes/µl whole blood will be considered AL, and cows that are positive on ELISA and PVL and have a lymphocyte count of 10,000 lymphocytes/µl whole blood or higher will be assigned PL status.Cows' BLV status will be determined 90 days prior to dry-off. At dry-off, we will also determine milk somatic cell count (SCC), lactose, protein and fat, and the microbiological status on all four quarters of each cow. Before the coliform mastitis challenge (day 0) and at days 2, 4, 6, 8 and 16, we will collect whole blood and serum to determine WBC, J5 titers (IgG1, IgG2, IgM), acute phase proteins (serum amyloid A and haptoglobin), cytokines (IL-1b, IL-6 and TNFα) lymphocyte distributions (CD4, CD8, CD25, CD45R0) and monocytes (M-G). Additionally, on those days, milk will be collected from all 4 quarters of cows to determine milk components (SCC, lactose, protein and fat) and microbiological status. BLV-ELISA and PVL status will also be determined at the time of the mastitis challenge and at days 8 and 16 post challenge. Proviral load will be determined using the CoCoMo qPCR. The E. coli challenge strain was isolated from a cow with naturally occurring mastitis, and it has been used previously by our lab. Serum samples will be used to assess anti-J5 E. coli IgM, IgG1, and IgG2 titers by ELISA as described previously by our group. Flow cytometric analysis will be used to phenotypically characterize isolated peripheral mononuclear cells via incubations with monoclonal antibodies specific for bovine leukocyte antigens. Interleukin-1β and IL-6 will be determined using commercial kits for sandwich ELISA of bovine IL-1β and bovine IL-6. Acute phase proteins (Amyloid A (SAA) and haptoglobin) will be determined using Tridelta assays. Aseptic foremilk samples will be collected at each milk sample collection period to determine infection status, milk components (lactose, protein and fat) and somatic cell counts (SCC). Vital signs, including rectal temperature, heart rate, respiratory rate and frequency of rumen contractions will be measured every 12 hours during the challenge period. Clinical status of all quarters will be recorded every time vital signs will be collected.Outcomes for this study may be considered continuous (e.g. lymphocyte counts), ordinal (e.g. mastitis clinical scores) and dichotomous (e.g. infection status of a quarter). Analyses of the effect of BLV-status on outcomes across time and at different time-points will be conducted using linear or generalized-linear mixed-effect regression models in a repeated (longitudinal) measures framework. Results will be reported as mean ± 95% confidence intervals and by frequencies for ordinal and dichotomous variables. Values of P< 0.05 will be considered significant.Objective 2. We will enroll a total of 1,180 cows across 10 herds (~590 BLV-negative, 413 BLV-AL, and 177 BLV-PL) in a prospective cohort study. For logistical reasons, cows will be enrolled in cohorts of approximately 6-15 cows. The inclusion criteria for all herds will be 1) milking >500 cows, 2) moderate (30%) to high (≥50%) BLV prevalence, 3) participating in DHI and/or uses DairyComp 305 as herd management software, and 4) do not use management practices aimed at reducing BLV transmission or prevalence. The primary outcomes of interest will be the incidence (number of new cases of disease during a specific time period) of mastitis and lameness since they are the two most costly clinical diseases to the dairy industry. In order to control for possible negative energy balance that may also affect the incidence of diseases during transition period, each cow will be tested for non-esterified-fatty-acids (NEFA) within the first 2 weeks of expected calving and b-hydroxybutyrate dehrydrogenase (BHBA) between 7 and 11 days post calving. The primary outcomes for this objective are infectious diseases, but additional health outcomes will also be measured, including but not limited to: rate of metabolic diseases (clinical ketosis, subclinical ketosis and displaced abomasum) and culling rate. Cows' BLV status will be determined as described for objective 1. Definitions of clinical disease outcomes will be provided to owners and managers of participating farms. All disease outcomes are dichotomous, i.e. disease-positive or disease-negative for any of the infectious or metabolic diseases. Subclinical ketosis will be defined as BHBA≥1.2 mmol/l. Herd owners and managers will be asked to enter clinical disease occurrences and treatments in their management software and these will be extracted later by study personnel. We will attempt to enroll herds which already use clinical disease definitions that are close to our definitions in order to reduce extra work and confusion for herds' treatment crews. We will use two measures of disease incidence: 1) cumulative incidence and 2) incidence density. Incidence risk ratios between study groups will be compared using multilevel mixed-effects generalized linear models using a binomial distribution (family) and log-link function. Incidence rate ratios between study groups will be compared using multilevel mixed-effects generalized linear models using a Poisson or Negative Binomial distribution (family) and the log link function. As cows are nested within herds, herd will be treated as a random effect for both the incidence risk and incidence rate ratios models. Results will be reported as mean ± 95% confidence intervals and by frequencies for ordinal and dichotomous variables. Values of P< 0.05 will be considered significant. Our research group will meet twice yearly for formative evaluation of the proposed studies. These meetings will serve to assure that we follow the proposed timeline and to address issues encountered that may warrant an alternative approach. The impacts of study results on the intended audiences will not be assessed directly. Nonetheless, results from the proposed studies will presented to dairy and veterinary audiences, and it will be included in educational material for veterinary and graduate students. The educational material will include BLV specific topics as well as topics related to veterinary epidemiology.

Progress 07/01/17 to 06/30/22

Outputs
Target Audience:Target Audiences Include: Veterinarians, Animal Researchers, Dairy Producers, Extension Personnel, Veterinary Students, Undergraduate and Graduate Students Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?A graduate student and the PI attended the Conference of Research Workers in Chicago, Illinois December 5-7, 2021 for professional development How have the results been disseminated to communities of interest?So far preliminary results from the project have been presented as a publication and at the Conference of Research Workers in Chicago, Illinois and the yearly Phi Zeta Research Meetings at the College of Veterinary Medicine, Michigan State University, East Lansing, Michigan. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Samples have been collected for objective 1 which was changed for the last reporting cycle report. The BLV diagnostics of ELISA, qPCR and lymphocyte counts were completed for those samples. For objective 2, a total of 2,668 and 2,294 samples were tested for BLV antibodies and Provirus by ELISA and qPCR, respectively. Complete blood counts were also determined for these samples. Some samples need to be rerun. Out of 885 samples collected at dryoff, 48% and 40% were positive on BLV ELISA and qPCR, respectively, and 51.4% of cows were negative on both tests. Twenty percent of cows had a lymphocyte count higher than 7,500. Thirty-nine-point six percent of cows were positive on ELISA and qPCR, and 17.4% and 22.3% of cows that were ELISA and qPCR positive had lymphocytes higher than 7,500 or lower than 7,500, respectively. Production data for all the cows enroll on eight farms have been collected, and they will be used for analysis of the impact of BLV on disease incidence. Sample collections were hampered by COVID and COVID outbreaks on some of the enrolled farms. Funds are secured to finish data analyses and publications for the next fiscal year.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: B. Norby1, R. Erskine1, C. Kellogg2, P. Bartlett1, P. Coussens3, T. Byrem4, D. Grooms5, L. Sordillo2. Impact of Bovine Leukemia Virus infection on disease incidence and severity in dairy cattle Poster., Conference of Research Workers in Animal Diseases, Chicago, Illinois, Dec 5-7, 2021. 1 Large animal Clinical Sciences, 2 Comparative Medicine and Integrative Biology, 3 Department of Animal Science, Michigan State University, East Lansing, MI , 4 Antel Biosystems, CentralStar Cooperative, East Lansing, MI, 5 Iowa State University College of Veterinary Medicine, Ames, Iowa
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: C. Kellogg1, B. Norby2, R. Erskine2, P. Bartlett2, P. Coussens3, T. Byrem4, D. Grooms5, L. Sordillo2 Changes in bovine leukemia virus diagnostic parameters in naturally infected dairy cattle over a lactation cycle. Poster., Conference of Research Workers in Animal Diseases, Chicago, Illinois, Dec 5-7, 2021. 1 Comparative Medicine and Integrative Biology, 2 Large animal Clinical Sciences , 3 Department of Animal Science, Michigan State University, East Lansing, MI , 4 Antel Biosystems, CentralStar Cooperative, East Lansing, MI, 5 Iowa State University College of Veterinary Medicine, Ames, Iowa


Progress 07/01/20 to 06/30/21

Outputs
Target Audience:Target Audiences Include: Veterinarians, Animal Researchers, Dairy Producers, Extension Personnel, Veterinary Students, Undergraduate and Graduate Students Changes/Problems:Due to delays caused by COVID restrictions, it has been necessary to change the goal for objective 1. We propose to change the focus from the effect of bovine leukemia virus status on experimental E. coli intramammary infection to the effect of bovine leukemia virus status on cows immune response to J5 vaccination used to prevent E. coli intramammary infections. We also believe the answers to this questions will be of more practical relevance to producers. For this revised objective,Serum samples and CBCs from 105 dairy cattle selected at random (35 each BLV-, BLV+ without Lymphocytosis, and BLV+ with Lymphocytosis) in their second or higher lactation will be used for this aspect of the study. The samples werecollected as part of Objective 1. Animal numbers are based on sample size estimates of BLV+ with Lymphocytosis animals having a 1/3 to ½ reduced IgG2 response to vaccination compared to BLV- animals.All animals will have received the same anti-E. colimastitis vaccine (Enviracor J-5 Escherichia Coli Bacterin, Zoetis, Parsippany, NJ or J-VAC by Merial, Boehringer Ingelheim, Duluth, GA) on the same schedule and animals will be placed in BLV status groups using BLV ELISA, qPCR and complete blood counts as described in Objective 1.Baseline titer, CBC, and BLV diagnosis by ELISA and qPCR will be conducted 4 weeks prior to vaccination and then titers will be determined ~2 weeks post vaccination at expected maximum humoral response. J5 E. coli whole cell antigen will be prepared following methods described in Erskine et al. 2011 and plated on 96 well plates.The J5 titer ELISA protocol will follow methods in Tyler et al. 1990.Serial dilutions for IgG1, IgG2, and IgM will be used for ELISA analysis in triplicate as described in Erskine et al. 2011. Log-transformed anti-E. colititers (IgG1, IgG2, and IgM) will be considered continuous variables and analyzed based on BLV status using a mixed linear model with repeated measures (enrollment and post vaccination).Assumptions will be checked following West et al., 2007.? What opportunities for training and professional development has the project provided?One Graduate student, oneundergraduate students were mentored on this project. Additionally, a research assistant/postdoc was mentored and hasworked on the project. . The PI and the graduate student attend the Conference of Research Workers in Animal Diseases in December, 2020,in Chicago, IL How have the results been disseminated to communities of interest?So far preliminary results from the project have been presented as a publicaton andat the Conference of Research Workers in Chicago, Illinois and the yearly Phi Zeta Research Meetings at the College of Verterinary Medicine, Michigan State University, East Lansing, Michigan. What do you plan to do during the next reporting period to accomplish the goals?The plans for the next reporting period are three fold fold: 1. Complete the qPCR tests for bovine leukemia virus and bovine leukemia virus ELISA tests. 2. Analyses of cows' bovine leukemia status and it's effect on developing clinincal disease during a lactation period for 1,063 cows in 8 dairy herds 3. Determine the effect of cows' bovine leukemia status on the response to J5 vaccination three times before and after parturition

Impacts
What was accomplished under these goals? Enrollement of animals for objective 2 has been completed and total of 1,063 dairy cows in 8 dairy herds were enrolled. All lymphocyte counts on all sampling points (n=1,923)have been complete. 1,027DNA extraction have been completed and are ready for qPCR testing for bovine leukemia virus. Likewise, over 2,300 serum samples are ready for analysis.

Publications

  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Wisnieski, L.; Norby, B.; Gandy, J.; Byrem, T.M.; Sordillo, L.M. (2020). Changes in bovine leukemia virus serological status and lymphocyte count between dry-off and early lactation in Michigan dairy cows. Journal of Dairy Science 113: 9473-9480. https://doi.org/10.3168/jds.2019-17839
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Kellogg,C.; Norby, B.; Erskine, R.; Bartlett, P.; Coussens, P.; Byrem, T.; Grooms, D.; Sordill, L. Impact of Bovine Leukemia Virus infection on disease incidence and severity in dairy cattle. Oral presentation, Conference of Research Workers in Anima Diseases, Dec. 4-8, 2020.


Progress 07/01/19 to 06/30/20

Outputs
Target Audience:The target audience includes: Veterinarians, researchers, dairy producers, extension personnel, veterinary student,undergraduate and graduate students. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One Graduate student and twoundergraduate students were mentored on this project. Additionally, a research assistant has been hired with internal funds to work on the project. The PI and the graduate student attend the Conference of Research Workers in Animal Diseases in November, 2019 inChicago, IL How have the results been disseminated to communities of interest?So far the results from the project have been presented at the Conference of Research Workers in Animal Diseases in20192018 in Chicago, IL. Furthermore, results have been presented at the Michigan State University, College of Veterinary Medicine, Phi Zeta Research day in 2019 in East Lansing, MI What do you plan to do during the next reporting period to accomplish the goals?The focus for the next reporting period is to initiate and complete objective 1) Determine the effect of BLV-status on hostresponses to experimentally induced coliform mastitis and to complete enrollment of the last 2-3 herds and accompanyingcows for objective 2) Determine the effect of BLV-status on the risk of cows developing naturally occurring infections during alactation period. Objective 1 was scheduled to start in the spring of 2020, but was postponed due to COVID-19 lockdown. Results from this project will be presented at the Conference of Resaerch Workers in Animal Diseases 2020 inChicago, IL. and at theMichigan State University, College of Veterinary Medicine, Phi Zeta Research day in 2020in East Lansing, MI

Impacts
What was accomplished under these goals? One more herd has had all animals enrolled since the last reporting period (7 total) and three more herds have been recruited and will have all remaining animals enrolled during the next reporting period.An additional 387 animals have been enrolled since the previous reporting period (total of 875 animals currently enrolled in the study) and more animals will be enrolled to include seasonal effects on each farm which is expected to be completed this upcoming spring. Data on white blood cell counts, ELISA for BLV-antibodies, qPCR for pro-viral load are currently being collectedand analyzed.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Impact of Bovine Leukemia Virus on lymphocyte counts and ELISA status across a lactation cycle in dairy cattle Conference of Research Workers in Animal Diseases Annual Conference, November 2019 in Chicago, IL
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Impact of Bovine Leukemia Virus on Dairy Cattle Lymphocyte and ELISA Status Over a Lactation Cycle. Michigan State University College of Veterinary Medicine Phi Zeta Research Day 2019 in East Lansing, MI
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Impact of Bovine Leukemia Virus Infection on Disease Incidence and Severity in Dairy Cattle Conference of Research Workers in Animal Diseases Annual Conference, November 2019 in Chicago, IL


Progress 07/01/18 to 06/30/19

Outputs
Target Audience:The target audience includes: Veterinarians, researchers, dairy producers, extension personnel, veterinary student, undergraduate and graduate students. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One Graduate student and 3 undergraduate students were mentored on this project. The PI and the graduate student attend the Conference of Research Workers in Animal Diseases December 2-5, 2018 in Chicago, IL How have the results been disseminated to communities of interest?So far the results from the project have been presented at the Conference of Research Workers in Animal Diseases December 2-5, 2018 in Chicago, IL Preliminary results have also been presented at the local Michigan State University Annual BLV Meeting on November 14th, 2018 What do you plan to do during the next reporting period to accomplish the goals?The focus for the next reporting period is to initiate and complete objective 1) Determine the effect of BLV-status on host responses to experimentally induced coliform mastitis and to complete enrollment of the last 2-3 herds and accompanying cows for objective 2) Determine the effect of BLV-status on the risk of cows developing naturally occurring infections during a lactation period. Results from this project will be presented at the Conference of Resaerch Workers in Animal Diseases November 2-5, 2019 in Chicago, IL.

Impacts
What was accomplished under these goals? Initial data from 88 heifers and cows on a dairy was collected every 2-4 weeks from 150 days prior to calving through dry-off after calving (~15-18 months). Data included determination of Bovine Leukemia Virus (BLV) serological status and Complete Blood Cell Counts to determine the animals' total lymphocyte counts. Data collection for the group of 88 animals completed in June 2019 and continued analysis and determination of BLV status throughout that study period is ongoing. Data on white blood cell counts, ELISA for BLV-antibodies, qPCR for pro-viral load are currently being collected from a total of 614 animals on 7 different Michigan dairy farms.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Longitudinal study of Bovine Leukemia Virus status in dairy cattle. Christopher Kellogg1, Bo Norby2, Ronald Erskine2, Paul Bartlett2, Jeff Gandy2, Paul Coussens3, Casey Droscha4, & Lorraine Sordillo2, 1) Comparative Medicine and Integrative Biology, 2) Large Animal Clinical Sciences, 3) Department of Animal Science, Michigan State University, 4) Northstar Cooperative, Lansing MI. Oral presentation/abstract at MSU, CVM, Phi Zeta Research Day, October 5th, 2018, East Lansing Michigan
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Impact of bovine leukemia virus on leukocyte counts and ELISA optical density status through dry-off & parturition in dairy cattle Christopher Kellogg1, Bo Norby2, Ronald Erskine2, Paul Bartlett2, Jeff Gandy2, Paul Coussens3, Casey Droscha4, Todd Byrem4, Daniel Grooms5, & Lorraine Sordillo2 1Comparative Medicine and Integrative Biology, 2 Large animal Clinical Sciences , 3 Department of Animal Science, Michigan State University, East Lansing, MI , 4 Antel Biosystems, Northstar Cooperative, East Lansing, MI, 5 Iowa State University College of Veterinary Medicine, Ames, Iowa Poster presentation/abstract at Conference of Research Workers in Animal Diseases (CRWAD), December 2nd to 5th, 2018, Chicago Illinois. 1Comparative Medicine and Integrative Biology, 2 Large animal Clinical Sciences , 3 Department of Animal Science, Michigan State University, East Lansing, MI , 4 Antel Biosystems, Northstar Cooperative, East Lansing, MI, 5 Iowa State University College of Veterinary Medicine, Ames, Iowa
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Impact of Bovine Leukemia Virus Infection on Disease Incidence and Severity in Dairy Cattle B. Norby1, L. Sordillo1; P. Bartlett1, P. Coussens2, R. Erskine1, D. Grooms3, T. Byrem4 1Deptment of Large Animal Clinical Sciences, and 2Department of Animal Science, Michigan State University, East Lansing, MI; 3Iowa State University, Ames, IA; 4NorthStar Cooperative, Lansing, MI Poster presentation/abstract at Conference of Research Workers in Animal Diseases (CRWAD) & USDA PI meeting, December 2nd to 5th, 2018, Chicago Illinois.


Progress 07/01/17 to 06/30/18

Outputs
Target Audience:The target audience includes for this project, includesveterinarians, researchers, dairy and beefproducers, extension personnel, veterinary students, undergraduate and graduate students. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One graduate student and 2 undergraduate students have been trained in blood sample collection and processing of samples for storage and later DNA extraction. Additionally, the students have been trained in DNA extraction for later qPCR determination of Pro-Viral load of dairy animals. The graduate student has been trained in conducting qPCR for BLV provirus using a new qPCR developed by our industry partner, NorthStar in Lansing, MI. The graduate student participated in regular lab meetings where our group discusses primarily developments in BLV research and statistical and epidemiological designs and methods, but which also includes professional development including how to conduct meetings, creating an "elevator speech" on their research, and resolving potential problems in the workplace. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?The plans for the next reporting period are to complete enrollment of dairy herds for objective 2 and to initiate the conduct of objective 1. The graduate student will present research findings at 2 local and 1 national research meetings

Impacts
(N/A)

Publications