Recipient Organization
MISSISSIPPI STATE UNIV
(N/A)
MISSISSIPPI STATE,MS 39762
Performing Department
(N/A)
Non Technical Summary
The use of antimicrobials in food animal production is of increasing societal importance. In the beef cattle industry, bovine anaplasmosis is an important, production-limiting disease that particularly affects the cow-calf sector. Currently, producers and veterinarians rely on the use of the antibiotic chlortetracycline (CTC) to control active outbreaks of bovine anaplasmosis. Chlortetracycline is most often provided to beef cows on pasture by including it in mineral supplement that is offered free-choice (i.e., the cow can choose to consume the CTC-medicated mineral or not at any time). Problems with this method of delivery include the inability of the producer to ensure that each cow receives an intended dose of CTC each day, and if cattle do not consume the intended dose, the CTC may not have its intended effect of reducing illness and death due to bovine anaplasmosis. Additionally, if cattle continuously consume less than the intended dose of CTC in a medicated mineral supplement, bacterial resistance to CTC may develop over time.This project intends to measure the amount of CTC-medicated mineral that cattle on pasture voluntarily consume over time, and subsequently calculate the dose of CTC received. With this knowledge, we will also collect blood samples from the cattle, and measure the concentration of CTC within the plasma to determine average amounts of CTC within the blood of the animal. Further, we will collect fecal samples and nasal swabs to investigate the difference in the microbial populations of the respiratory and gastrointestinal tracts of animals being fed a CTC-medicated mineral compared to those fed and non-CTC-medicated mineral. The ultimate goals of this project are to improve the collective knowledge of best practices for reducing illness and death in cow-calf herds due to bovine anaplasmosis, while also improving antimicrobial stewardship in beef cow-calf herds. Our team hopes to provide veterinarians and beef cattle producers with information that can be used when designing programs and strategies for reducing the risk of illness and death due to bovine anaplasmosis.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Goals / Objectives
The overarching goal of the project entitled "Antimicrobial stewardship in beef production: Impacts of chlortetracycline exposure to beef cows on pasture" is to improve antimicrobial use practices in the cow-calf sector of beef production. The specific objectives of this study include: 1) quantify the dose of chlortetracycline (CTC) received by cattle on pasture when offered a CTC-medicated mineral supplement free choice, 2) quantify the plasma CTC concentrations that result from individual dose received, and 3) determine the resulting impact of mineral supplementation and CTC exposure on respiratory and gastrointestinal microbiomes of beef cows on pasture. The cow-calf sector is the foundation of the beef industry, and practices on these operations impact the health and performance of beef calves that matriculate through the subsequent stages of the beef production chain (i.e., stocker/backgrounder and feeding sectors). Chlortetracycline is commonly provided to beef cattle on pasture by CTC-medicated mineral fed free choice for the purpose of controlling outbreaks of bovine anaplasmosis. This project intends to: 1) provide veterinarians, beef cattle producers, and other beef cattle health personnel with information describing the use of CTC in beef cows on pasture, 2) inform best management practices for the use of free-choice minerals supplements as a vehicle to deliver CTC to cows on pasture, and 3) inform future research focusing on methods of mitigating morbidity and mortality due to bovine anaplasmosis.
Project Methods
This project will be conducted under management conditions similar to those of a typical beef cow-calf operation in the southeast U.S. Following a 14 day adaptation period, the intake of CTC- and non-CTC-medicated mineral offered free-choice to cattle will be monitored for a total of 6 months. Using intake data for individual cows, the daily dose received of CTC-medicated mineral will be calculated. Blood samples will be collected in 30-day intervals to quantify plasma CTC, and fecal and nasal secretion samples will be used to monitor impact of CTC-exposure on respiratory and gastrointestinal microbiome. Results will be analyzed as appropriate for varying data types (i.e., consumption data vs. microbiome data).