Evaluation of high-protein diets differing in protein source in healthy adult dogs

Given the dynamic market for protein-based ingredients in the pet food industry, demand continues to increase for both plant- and animal-based options. Animal and plant protein sources contain different amino acid profiles and vary in digestibility, which can affect the protein quality provided to the animal. The objective of this study was to evaluate the apparent total tract digestibility of canine diets differing in protein source and test their effects on serum metabolites, whole blood gene expression, and fecal characteristics, metabolites, and microbiota of healthy adult dogs consuming them. Four isocaloric and isonitrogenous extruded diets were formulated to meet all Association of American Feed Control Officials (AAFCO) nutrient profiles for adult dogs at maintenance, with the primary difference being protein source: 1) chicken by-product meal (CBPM), 2) deboned chicken, dried chicken, and spray dried chicken (DC), 3) corn gluten meal (CGM), or 4) wheat gluten meal (WGM). Twelve adult spayed female beagles (BW = 9.9± 1.0 kg; age = 6.3 ±1.1 yr) were used in a replicated 4×4 Latin square design (n=12/treatment). Each period consisted of a 22-d adaptation phase, 5 d for total and fresh fecal collection, and 1 d for blood collection. Fecal microbiota data were analyzed using QIIME 2.2020.8. All other data were analyzed using the Mixed Models procedure of SAS version 9.4. Fecal scores were higher (p<0.05; looser stools) in dogs fed DC or CBPM than those fed WGM or CGM, but all remained within an appropriate range. Apparent dry matter digestibility was lower (p<0.05) in dogs fed CBPM or CGM than those fed DC or WGM. Apparent crude protein digestibility was also lower (p<0.05) in dogs fed DC or CGM than those fed WGM. Dogs fed CBPM had lower (p<0.05) apparent organic matter, crude protein, and energy digestibilities than those fed the other 3 diets. Fecal indole concentrations were higher (p<0.05) in dogs fed CBPM than those fed WGM, but phenol and total phenol and indole concentrations were not different. Fecal total short-chain fatty acid (SCFA) concentrations were higher (p<0.05) in dogs fed DC than those fed CGM, but individual SCFA (i.e., acetate; propionate; butyrate) were not different. Fecal total branched-chain fatty acid concentrations were higher (p<0.05) in dogs fed DC or CBPM than those fed WGM. Fecal ammonia concentrations were higher (p<0.05) in dogs fed the animal-based protein diets than those fed the plant-based protein diets. Gene expression was not affected by diet. The relative abundance of 3 bacterial phyla and 9 bacterial genera were significantly shifted among treatment groups (p<0.05). Considering AA profiles and digestibility data together, the protein sources of the DC diet provided the most and highest quality protein without AA supplementation of all diets tested. However, the animal-based protein diets resulted in higher concentrations of proteolytic fermentative end-products. Further studies evaluating moderate dietary protein concentrations are needed to better compare plant- and animal-based protein sources.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Animal Sciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2022

Author dc:creator

• Sieja, Kelly Marie

Contributors dc:contributor

• Swanson, Kelly S

• canine
• nutrition
• protein

Statement dc:rights

• Copyright 2022 Kelly Sieja

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/115611

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F115611