Location: Food Science and Market Quality and Handling Research Unit
Project Number: 6070-43440-013-002-N
Project Type: Non-Funded Cooperative Agreement
Start Date: Sep 1, 2023
End Date: Sep 30, 2026
Objective:
1. To prepare peanut skins and/or polyphenolic extract for in vitro antimicrobial activity assessment and in vivo as a feed additive.
2. Conduct dose-response in vitro assessment of the antimicrobial activity of polyphenolic peanut skin extracts against Salmonella and Campylobacter, which are foodborne pathogens commonly found within turkey production environments of public health concern using the minimum inhibitory concentration using the broth dilution method (Kowalska-Krochmal & Dudek-Wicher, 2021).
3. To formulate and prepare in vivo peanut skin experimental turkey diets.
a. Formulate three corn and soybean meal grower phase (starter, grower, and finisher) turkey diets with and without peanut skins using Concept 5 feed formulation software to meet and or exceed the nutrient requirements for turkeys based upon the National Research Council (1994).
b. Acquire all necessary feed ingredients and have them delivered and stored at the NC State University Feed Mill.
c. Schedule feed mixing date for all experimental turkey diets at the NC State University Feed Mill and plan short-term storage.
4. Conduct in vivo turkey feeding study to determine the dose-response antimicrobial activity of peanut skins and/or polyphenolic extracts (0%, 2%, 4%, 6%) on the proliferation of Salmonella Heidelberg within the organs and intestine of the turkey and prevalence within the production environment (litter, feed, and water).
a. To inoculate turkey hatchlings with 1010 CFU/mL Salmonella Heidelberg at day 2 post-hatch.
b. To collect and enumerate fecal, litter, water, and feed samples for Salmonella Heidelberg colony forming units at 14 days and 21 days of age.
c. To collect liver, spleen, ileum, and ceca and enumerate Salmonella Heidelberg colony forming units at 28 days of age to determine organ invasion and intestinal colonization.
d. To collect turkey breast meat samples to enumerate Salmonella Heidelberg colony forming units to assess possible cross-contamination during processing (deboning and cutting up for components) and to assess turkey meat samples for the presence of peanut allergens.
6. Determine live performance and animal health of in vivo turkey feeding trials using peanut skins and/or peanut skin extracts as an antimicrobial feed additive.
a. Bi-weekly collect body weights and weekly collect feed weights to determine feed intake and calculation of feed conversion ratio.
b. At study termination, collect tissue samples from turkeys to determine the effect on total hepatic glycogen and blood.
c. At study termination, ileal and cecal contents will be harvested to examine the microbiota populations.
Approach:
Locally sourced peanut skins will be ground, and peanut skin polyphenolic compounds will be extracted using solvent extraction methods. In vitro methodologies will be utilized to determine the antimicrobial activity of peanut skin extracts against Camplyobacter jejuni and Salmonella Heidelberg using disc diffusion methods and the minimum inhibitory concentration method will be utilized to determine the lowest concentration of the peanut skin extract to inhibit in vitro bacterial growth. In vivo studies turkey feeding trials will be conducted to determine the utilization of peanut skins and/or extracts as an antimicrobial feed additive. Three hundred twenty hatchlings will be randomly assigned to 8 treatments with 40 poults per treatment housed in separate rooms. Poults will be fed a conventional corn and soybean meal turkey basal starter diet with inclusion of peanut skins or extracts at 0%, 2%, 4% or 6% for 28 days. On day 2 of age, poults will either be orally gavaged with 1 mL of 1010 colony forming units/mL of Salmonella Heidelberg or sterile phosphate buffered saline. Organs (liver and spleen) will be enumerated to determine Salmonella organ invasion (day 14, 28). Intestinal contents (ileum and cecal) will be enumerated to determine Salmonella colony forming units/mL and for analysis of the gut microbiota (day 14, 28). Fecal, litter, feed and water samples will be collected on day 14, 21, and 28 and enumerated to determine Salmonella colony forming units/mL within the turkey production environment. At day 28 turkey breast meat samples will be enumerated for Salmonella, assessed for quality parameters, presence of peanut allergens, and proximate composition.
