Understanding the role of host-pathogen interactions and the impact of management system on antimicrobial resistance in Brazilian livestock systems

了解宿主-病原体相互作用的作用以及管理系统对巴西畜牧系统抗菌素耐药性的影响

基本信息

批准号：
BB/R022739/1
负责人：
Caroline Rymer
金额：
$ 9.43万
依托单位：
University of Reading
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2018
资助国家：
英国
起止时间：
2018 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FR022739%2F1
关键词：
Understanding role host pathogen interactions

项目摘要

The Brazilian beef industry is immense, and is a vital source of foreign revenue for the country. Brazil is the second largest producer of beef in the world, and has the world's largest commercial herd of approximately 200 million head produced on 1.8 million farms ranging from small enterprises (<500 head p.a.) to commercialised beef production enterprises (>4000 head p.a.). Most animals are produced on pasture, many of them on soils of low to medium fertility in the cerrado (similar to savannas, an important biome in Brazil) with <7% of slaughtered animals being produced on feedlots. Despite this extensive system of beef production, antimicrobial consumption is high. In 2010, Brazil was ranked third highest in the world for antimicrobial consumption by food producing animals, and accounted for 9% of total global farm animal antimicrobial consumption. This high consumption of antimicrobials by farm animals increases the risk of the development of antimicrobial resistant (AMR) bacteria in the host animal's microbiome (the microbial population living in the animal's gut). There are many factors which might encourage the proliferation of AMR bacteria in the host gut, and the hypothesis on which this proposal is based is that changes in the host microbiome may affect the maintenance and prevalence of AMR strains of bacteria. Identifying interventions that may then encourage the development of a microbiome that suppresses AMR bacteria could then help control the development and spread of AMR in Brazilian beef cattle. We hypothesise that beef finished on pasture in Brazil will have a lower prevalence of faecal AMR bacteria compared with those finished in feedlots, because of the less intensive nature of the pasture based production system. Much of the pasture grazed in Brazil is suitable either for the growth of tropical grasses or, in more intensively managed pastures, legumes. Both tropical grasses and forage legumes contain tannins, which are known to have antimicrobial properties and antibiotic resistance modifying properties. However, the efficacy and mode of action of tannins as antimicrobials depends on their concentration and composition. Elucidating the relationship between tannin composition and intake, and the effect this has on the host animal's microbiome (and susceptibility to AMR bacteria) will be investigated in this project. In the first stage of the project, we will conduct a survey to determine the effect of animal age (yearling and finishing animal) and production system (cerrado grazing, more intensively managed pasture, feedlot) on the prevalence of AMR bacteria in faecal samples taken from beef cattle in Brazil. We will also determine the composition of the microbial population in the animal's gut (from the faecal sample) to investigate whether there are patterns of bacterial species which are associated with a lower prevalence of AMR bacteria. We will also take samples of the forages consumed by the animal and investigate whether the amount and composition of tannin that the animal consumes can explain differences in its gut microbiome and the prevalence of AMR bacteria. This will then enable us to develop management and feeding strategies (that would be investigated in the second stage of the project) that might reduce the prevalence of AMR bacteria in Brazilian beef cattle, improving the health status of the cattle themselves and improving the safety and marketability of the meat.

巴西牛肉产业规模巨大，是该国外汇收入的重要来源。巴西是世界第二大牛肉生产国，拥有世界上最大的商业牛群，180 万个农场生产约 2 亿头牛，范围从小型企业（每年<500 头）到商业化牛肉生产企业（每年>4000 头）。。大多数动物是在牧场上生产的，其中许多是在塞拉多（类似于热带稀树草原，巴西的重要生物群落）低到中等肥力的土壤上生产的，不到 7% 的屠宰动物是在饲养场生产的。尽管牛肉生产系统规模庞大，但抗菌药物的消耗量仍然很高。 2010年，巴西的食用动物抗菌药物消费量位居世界第三，占全球农场动物抗菌药物消费总量的9%。农场动物对抗菌药物的大量消耗增加了宿主动物微生物群（生活在动物肠道中的微生物群）中产生抗菌药物耐药性 (AMR) 细菌的风险。有许多因素可能会促进 AMR 细菌在宿主肠道中增殖，该提议所依据的假设是宿主微生物组的变化可能会影响 AMR 细菌菌株的维持和流行。确定可能促进抑制抗菌素耐药性细菌的微生物组发展的干预措施，有助于控制抗菌素耐药性在巴西肉牛中的发展和传播。我们假设巴西牧场生产的牛肉与饲养场生产的牛肉相比，粪便 AMR 细菌的流行率较低，因为牧场生产系统的集约化程度较低。巴西放牧的大部分牧场适合种植热带牧草，或者在管理更集约的牧场中适合种植豆科植物。热带草和饲料豆类都含有单宁，已知单宁具有抗菌特性和抗生素耐药性调节特性。然而，单宁作为抗菌剂的功效和作用方式取决于其浓度和成分。本项目将研究阐明单宁成分与摄入量之间的关系，及其对宿主动物微生物组（以及对 AMR 细菌的易感性）的影响。在该项目的第一阶段，我们将进行一项调查，以确定动物年龄（一岁动物和育成动物）和生产系统（塞拉多放牧、更集约化管理的牧场、饲养场）对粪便样本中 AMR 细菌流行率的影响来自巴西的肉牛。我们还将确定动物肠道（来自粪便样本）中微生物种群的组成，以研究是否存在与 AMR 细菌较低流行率相关的细菌种类模式。我们还将采集动物消耗的草料样本，并研究动物消耗的单宁的含量和成分是否可以解释其肠道微生物群的差异和抗菌素耐药性细菌的流行。这将使我们能够制定管理和饲养策略（将在项目第二阶段进行研究），以减少巴西肉牛中 AMR 细菌的流行，改善牛本身的健康状况，并提高安全性和安全性。肉的适销性。

项目成果

期刊论文数量（3）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Taxonomy and Functional Diversity in the Fecal Microbiome of Beef Cattle Reared in Brazilian Traditional and Semi-Intensive Production Systems.

DOI：
10.3389/fmicb.2021.768480
发表时间：
2021
期刊：
Frontiers in microbiology
影响因子：
5.2
作者：
Corrêa PS;Jimenez CR;Mendes LW;Rymer C;Ray P;Gerdes L;da Silva VO;De Nadai Fernandes EA;Abdalla AL;Louvandini H
通讯作者：
Louvandini H

Antimicrobial resistance in Brazilian cattle systems

巴西牛系统中的抗生素耐药性