The Microbial Modifying Properties of Re-used Chicken Litter and Iodinated Water on Poultry Health and Disease Resistance

• Author / Creator

  Pepin, Deanna

• In animal production the overuse of antibiotics has generated numerous multidrug resistant bacteria that pose significant health risks for both humans and animals. Reducing the use of antibiotics in poultry production relies on finding ways to prevent the introduction and spread of pathogens through a flock, as well as promoting the health and development of a flock to be resilient against such infections. Water lines have been identified as a means through which pathogens can spread throughout flocks and current water sterilization methods are not effective against all bacterial pathogens and viruses. Iodinated water is one method of water sterilization that may prove to prevent pathogen spread. The use of iodine as an antimicrobial in water sterilization has long been reported, and increased iodine in poultry feed has resulted in improved production parameters. The mechanisms involved in iodine’s efficacy on poultry performance are poorly understood. As well as preventing pathogens, research has been looking at ways to improve poultry resilience through the development of a healthy intestinal microbiome that excludes pathogens. The microbial community in the intestines plays an important role in disease resistance, immune development, host digestion and nutrient absorption. One way to encourage the early development of the microbiome in chicks is by placing them on already used chicken litter, which contains a diverse microbial community from adult chicken fecal droppings. Research has shown that used litter impacts the development of the chick intestinal microbial community, and has improved infection resistance to poultry pathogens such as Salmonella. However, the impact of used chicken litter on the intestinal development and immune education in birds is not well characterized. To better understand the mechanisms behind re-used litter and iodinated water in poultry health 1-day-old broiler chicks were supplied with regular water or two concentration of iodinated water and clean or used litter in a 2 by 3 factorial design to determine the effect of treatment on the caecal microbiome, gene expression, and morphology over 12 days of treatment. Next, it was determined if these treatments were capable of reducing Salmonella enterica serovar Enteritidis colonization, comparing regular water or 1 ppm iodinated water and clean or used litter. Lastly, the long-term effect of iodinated water on poultry performance and intestinal microbial communities was analyzed over 35 days of growth. Overall, used litter had a significant effect on promoting early development of the caecal microbial community, introducing numerous bacteria not found in the clean litter treatment, and modifying short chain fatty acid profile in the caeca. As well, used litter modified caecal morphology and the caecal gene expression increasing genes related to intestinal epithelial cell homeostasis as well as activating an immune response. Used litter proved to be effective in reducing Salmonella colonization, and reduced potentially pathogenic members of the Enterobacteriaceae family, but introduced Clostridium, a genus also known for its pathogenic species. Iodinated water had very limited effects on the microbiome, gene expression, gut morphology and growth parameters measured in both the used litter chicks over 12 days and the adult birds over 35 days. However, the largest impact of iodinated water was seen in the clean litter treatment, with risks of increasing Salmonella colonization, and playing a role in intestinal epithelial cell turnover and organization as well as activating genes associated with a proinflammatory response. Overall, further research is needed to understand the effect of iodinated water to farm water in a production setting. The re-use of chicken litter has many benefits for the early development of the intestinal microbial community in poultry, however does come with risks of pathogen introduction.

• Subjects / Keywords

  • Poultry health
  • Salmonella infection
  • Poultry cecal microbiome
  • Poultry cecal transcriptome
  • Chicken litter reuse
  • Iodine water

• Graduation date

  Fall 2018

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3HT2GT5H

• License

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