UK team investigates the impact of zinc oxide ban in pig diets

The ban, effective this month in the UK, is due to concerns that zinc oxide in weaning piglets' diets may contribute to AMR. Zinc oxide has traditionally been used to prevent post-natal weaning diarrhea (PWD) in piglets.

Running until 2027, this initiative is aimed at helping the UK pig industry adapt to this regulatory change while maintaining piglet health and welfare. Researchers will monitor bacterial levels causing PWD and AMR in pig herds before and after the ban.

When asked how prepared the UK pig industry is for the prohibition of ZnO, the Roslin Institute’s Dr Deborah Hoyle told FeedNavigator: “The industry has been preparing for this change over the past two years, with guidance​​ and advice provided through various national producer associations and industry bodies.”

The consortium project, she continued, aims to provide a barometer of piglet health across the recruited UK farms during the transitional period of ZnO withdrawal, she continued.

“By collaborating closely with producers and leveraging baseline samples from a previous pilot project, the study will assess the industry's readiness and the impact of the ZnO ban on commercial pig herds.”

Piglet resilience 

The researchers will also analyze the genetic makeup of PWD-causing bacteria and the pig gut microbiome to understand the withdrawal's impact.

“The project seeks to better understand how zinc acts within the gut to enhance piglet resilience to disease, so that this knowledge can then be taken forward in the future to inform the development of alternative strategies,” said Dr Hoyle, who has a background in veterinary medicine and the epidemiology of zoonotic and emerging pathogens, antimicrobial resistance, surveillance and disease control.

Of the monies granted, resources will be dedicated to field sampling, laboratory analysis, detailed cohort studies investigating ZnO action, and stakeholder knowledge engagement and translation activities.

Multidisciplinary approach​

The consortium includes partners from Queen’s University Belfast, the UK’s Animal and Plant Health Agency (APHA), Scotland’s Rural College (SRUC), Edinburgh Napier University, the University of Surrey, and industrial partner, AB Neo.

“The multidisciplinary collaboration will enhance the research outcomes by integrating cutting-edge science with practical application in the pig industry,” according to Dr Hoyle.

• The Roslin Institute leads the overall project consortium, together with the longitudinal field survey and bio-epidemiological components.
• Queen’s University is conducting detailed investigations on the actions of ZnO on the piglets’ microbiome during weaning and through to the finishing stage.
• APHA is studying the genomic composition of the ETEC bacteria responsible for the disease, and diversity of AMR genes in the presence and absence of ZnO.
• SRUC leads stakeholder knowledge exchange and translational activities, and through producer engagement seeks to better understand their views on the impact of the ZnO ban on pig health, welfare, and their farming enterprises.
• The University of Surrey and Edinburgh Napier University are project partners providing expertise in molecular diagnostics, microbiome, and transmission of livestock disease
• AB Neo contributes practical industry insights and supports the application of research findings in real-world settings. 

All the consortium members will contribute to stakeholder engagement and translation activities. “The project will provide evidence to inform wider discussions within the pig industry as it adjusts to the ZnO ban. This includes publishing results in scientific journals, presenting findings at industry conferences, and direct communication with pig farmers.”

Diagnostic assays and genome sequencing technologies​

As regards the methodologies that will be used to monitor levels of bacteria responsible for PWD and AMR, Dr Hoyle explained that the team will take longitudinal sampling of dung from 24 commercial pig farms across the UK.

“This will include diagnostic assays and genome sequencing technologies to monitor the prevalence of causative bugs enterotoxigenic Escherichia coli (ETEC) and rotavirus, alongside AMR markers, before and after the ZnO ban."

Metagenomic and strain analysis will also be conducted to identify changes in bacterial populations and resistance genes that may occur before and after ZnO withdrawal, she said.

The researchers will utilize genomic approaches as well to analyze disease-causing bugs and the piglets’ gut microbiome, reported the lecturer. The work will involve bacterial strain isolation and detailed characterization of diversity, virulence-associated genes, and antimicrobial resistance markers.

Additionally, the team will gather data on farm management and husbandry practices through surveys and interviews. They will also interview producers to understand their perspectives on the impact of the zinc oxide ban on pig health, welfare, and their farming operations. This approach aims to contextualize the findings within the real-world challenges farmers face.