The Effect of α-Monolaurin and Butyrate Supplementation on Broiler Performance and Gut Health in the Absence and Presence of the Antibiotic Growth Promoter Zinc Bacitracin.

Bakang R Letlole,Ellen P C W Damen,Christine Jansen Van Rensburg

doi:10.3390/antibiotics10060651

Bakang R Letlole, Ellen P C W Damen + Show 1 more

Open Access

https://doi.org/10.3390/antibiotics10060651

Copy DOI

Journal: Antibiotics (Basel, Switzerland)	Publication Date: May 29, 2021
Citations: 9	License type: CC BY 4.0

Affiliation: University of Pretoria

Abstract

The use of antibiotic growth promoters (AGP) is common practice to improve broiler production and performance. The use of AGP is under discussion as it can induce bacterial resistance. The purpose of this study was to determine the impact of removing AGP from broiler feed and study the effect of feed additives. For those countries where in-feed AGP are still permitted, the effect of the products in the presence of AGP was evaluated. Half the number of male broilers received a diet free of AGP, whereas the other half received a diet supplemented with zinc bacitracin at 0.5 g/kg. Both diets were either without additional additives or combined with a coated sodium butyrate, α-monolaurin or a combination of these additives. Raised under optimal conditions, the incorporation of AGP had no effect on broiler performance, but negatively affected villi height and villi height to crypt depth (VH:CD) ratio in the duodenum. In the absence of AGP, butyric acid and α-monolaurin had a positive effect on villi height. In the presence of AGP, α-monolaurin resulted in the lowest feed conversion ratio and improved VH:CD ratio in the duodenum, jejunum and ileum. Both feed additives had minimal effect on performance parameters but showed small positive effects on gut health in the absence of AGP and could play a role in the strategy to replace AGP.

Highlights

The Food and Agriculture Organization paints a bleak picture, reporting a deteriorated food security and raised numbers of malnutrition in many countries across the world [1]
Body weight, feed intake and feed conversion ratio (FCR) were not affected by the antibiotic growth promoter
This is in contrast with previous findings that showed clear growth-promoting effects and improved feed efficiency during the production cycle of broilers supplemented with zinc bacitracin [17,18,19]

Summary

Introduction

The Food and Agriculture Organization paints a bleak picture, reporting a deteriorated food security and raised numbers of malnutrition in many countries across the world [1]. Multiple modes of action for the growth-promoting effect of antibiotics in livestock have been determined, including a reduction in nutrient losses to microorganisms colonizing the gastrointestinal tract (GIT), altering microbiome diversity, reducing growth inhibiting microbial metabolites and prevention of sub-clinical disease [2,3]. There is criticism of the use of in-feed antibiotics as its use in food-producing animals can cause pathogenic microorganisms to become resistant, making human and animal diseases hard to treat [4,5], presenting a serious threat to public health. Potential AGP alternatives must be able to reduce the number of pathogens, shift the microbiome towards more beneficial bacteria, [6] improve the efficiency of nutrient utilization by the growing animal and improve its immune response [7]. Derivatives of fatty acids such as sodium butyrate and α-monolaurin may be a solution

Objectives

Methods

Results

Conclusion