94 Sustainable Feeding Solutions Across the Animal Kingdom: Identifying and Implementing
Authors: Dierenfeld Ellen S 
Published: November 2023

Abstract
To meet planetary limits, proactive sustainable solutions must be rapidly elevated across various sectors of the feed industry, with attention from production/selection of raw ingredients through diet manufacturing and formulation processes to precision nutrition programs targeting all animal species including livestock and poultry, pets, and managed wildlife. Responsible sourcing encompasses commitments for tracking environmental impact metrics of feeding systems, with various public calculation tools available. Sustainability data are starting to be incorporated into ingredient descriptions and formulation software for more widespread and standard use as marketing, economic and/or important conservation messaging. Ingredient strategies for sustainable food systems include regenerative agriculture practices, which are typically more holistic and address local needs, with resultant environmental benefits such as decreased water use or increased soil health, biodiversity, and resilience. Substitution of pulses (peas, beans) or other proteins for soybeans, multiple layers/species incorporated into cropping systems, low water use ingredients (i.e., hempseed or sorghum) can result in more intact ecosystems, better water balance, reduced greenhouse gas (GHG) emissions and increased carbon sequestration, with measurable impacts. Such options will become even more critical for global health with continuing climate change. Bio-circularity, which increases the use of residues, by- and co-products, or incorporates excess food streams to provide value-added sustainable feedstuffs serves to decrease GHG emissions from landfills/compost and can reduce the risk of commodity crop land conversion. Such ingredients, often niche or opportunistic, represent nearly 30% of global feed intake and may decrease food-feed competition as well as free up global arable land. Byproduct portions often contain quite suitable nutritional as well as sustainable feed ingredient profiles, and can be further enhanced through dehydration, fermentation, or upcycling as dietary substrates for insects, which are then incorporated into diets as alternative protein sources. Examples of common circular ingredients include processed and spent fermented grains, as well as bakery, fruit/vegetable, and retail excesses. Feeding Innovations that improve the carbon footprint through increased efficiency, productivity and/or health can reduce pressure on production (both animal and feed manufacturing) landscapes. Enzymes, pro- and pre-biotics, and additives fit under this broad category, as do the use of single cell proteins and fermentation products. While specific ingredients may directly or indirectly reduce GHG emissions (seaweeds, tannins, fats) through impacts on the rumen or hindgut microbiota, innovations are not limited to diets per se but rather encompass technologies, tools and entire feeding systems. The use of harvested natural plant sources (e.g., Miscanthus spp. grass, wood sawdust, local browses) as low-starch fiber ingredients in addition to (or in lieu of) cultivated forages represents sustainable value-add products, contributing to improved animal health with a focus on local producers/communities; environmental impacts should be monitored. Similarly, harvest and processing of edible invasive species for consumption as part of sustainable management/eradication programs must be considered. Logistically, policy barriers and scaling such efforts may prove the biggest challenges both regionally and globally; nonetheless, sustainability efforts are essential.