Historically, the primary plant proteins utilized in pet food applications included soy, corn, and wheat proteins; however, pea, potato, and rice proteins have emerged in recent years as other viable plant-based options.2
Protein is of utmost importance when considering adequate nutrition for pets. The Association of American Feed Control Officials (AAFCO) establishes minimum protein guidelines for pets in the United States. According to AAFCO, the minimum protein requirement for adult dogs is 18% and 22.5% for puppies, to support growth and reproduction.3 The minimum protein requirement for adult cats is 26% and 30% for kittens, to support growth and reproduction.3Interestingly, as consumers' interest in the utilization of plant protein sources in pet food increases, there are currently no regulatory standards or evidence-based data to determine the percentage of protein that should come from plant versus animal sources, or if it even matters.
Dietary protein is necessary to provide essential amino acids and build protein reserves in the body.4 Some plant proteins are commonly used in pet food applications for their complementary amino acid profile when paired with other proteins and grain sources.5,6 In general, plant-based ingredients are thought to have less variable nutrient composition when compared with animal-based ingredients.6,7
It is well established that dogs and cats who consume complete and balanced plant-based diets maintain overall health compared to animal protein-based diets.8,9 In addition, studies have observed that plant-based pet diets can have comparable nutrient digestibility as animal-based pet diets with similar nutrient profiles.6,10,11 This is true for both dogs and cats. A recent study by Golder et al.12 noted that cats can potentially digest plant proteins more fully and efficiently than dogs.12 However, these research studies are still limited, and the long-term effects are not as well studied. With that, pets that do not have a food aversion to animal-based proteins can still consume these diets and can maintain a supply of essential amino acids.
As consumer interests shift toward plant-based diets, new plant proteins will continue to be identified and utilized in pet food applications. These may include testing these new ingredients for safety evaluation before entering the pet food market, long-term data collection on the impact of health on pets, and sustainability.
Source: BSM Partners
References
Loeb, J. 2020. The trouble with vegan cats and dogs. Vet Rec. 186(7):197.
Domínguez-Oliva, A, Mota-Rojas, D, Semendric, I., Whittaker, AL. (2023). The impact of vegan diets on indicators of health in dogs and cats: A systematic review. Vet. Sci. 10(1):52. DOI:10.3390/vetsci10010052.
2024. Official Publication; Association of American Feed Control Officials: Champaign, IL, USA.
Laflamme, DP. 2008. Pet food safety: Dietary protein. Topics Companion. Anim. Med. 23(3):154-157.
Hill, D. 2004. Alternative proteins in companion animal nutrition. In Pet Food Association of Canada Fall Conference.
Bednar GE, Murray SM, Patil AR, et al. 2000. Selected animal and plant protein sources affect nutrient digestibility and fecal characteristics of ileally cannulated dogs.Arch. Anim. Nutr. 53:127–140. DOI: 10.1080/17450390009381942.
Vanelli, K, de Oliveira, ACF, Sotomaior, CS, Weber, SH, Costa, LB. 2021. Soybean meal and poultry offal meal effects on digestibility of adult dogs diets: Systematic review. PloSone. 16(5):e0249321. DOI: 10.1371/journal.pone.0249321
Linde, A, Lahiff, M, Krantz, A, Sharp, N, Ng, TT, Melgarejo, T. 2023. Domestic dogs maintain positive clinical, nutritional, and hematological health outcomes when fed a commercial plant-based diet for a year. bioRxiv, 2023-02.
Clapper, GM, Grieshop, CM, Merchen, NR, Russett, JC, Brent, JL, Fahey, GC. 2001. Ileal and total tract nutrient digestibilities and fecal characteristics of dogs as affected by soybean protein inclusion in dry, extruded diets. J. Anim. Sci. 79(6):1523-1532.
Liversidge, BD, Dodd, SA, Adolphe, JL, Gomez, DE, Blois, SL, Verbrugghe, A. 2023. Extruded diet macronutrient digestibility: Plant-based (vegan) vs. animal-based diets in client-owned healthy adult dogs and the impact of guardian compliance during in-home trials. Frontiers Anim. Sci. 4:1288165.
Bednar, GE, Patil, AR, Murray, SM, Grieshop, CM, Merchen, NR, Fahey, GC. 2001. Starch and fiber fractions in selected food and feed ingredients affect their small intestinal digestibility and fermentability and their large bowel fermentability in vitro in a canine mode. J. Nutr. 131(2):276-286.
Golder, C, Weemhoff, JL, Jewell, DE. 2020. Cats have increased protein digestibility as compared to dogs and improve their ability to absorb protein as dietary protein intake shifts from animal to plant sources. Anim. 10(3):541. DOI:10.3390/ani10030541.
About the Author: Ada-Miette Thomas received both bachelor's and master's degrees in food science with an emphasis on nutrition. Ada-Miette conducted research with a focus on human nutrition and studied the effects of carbohydrate sources on markers of Metabolic Syndrome in adults.