Green ingredients for improving resilience and sustainability in animal feeding for livestock and aquaculture

Resilience in agricultural systems refers to the capacity to adapt and thrive amidst challenges such as climate change, resource scarcity, or economic disruptions, all while maintaining productivity and efficiency. In the context of animal feeding, this concept entails the development of flexible, adaptive systems that ensure a consistent feed supply and safeguard animal health and welfare under external pressures. Sustainability, on the other hand, involves meeting the needs of the present without compromising the ability of future generations to meet theirs. It emphasizes environmental conservation, economic viability, and social equity. For livestock production, this translates into minimizing environmental impacts while enhancing productivity, animal welfare, and product quality. Today, both resilience and sustainability face unprecedented strain. Global challenges, such as including the COVID-19 pandemic, the Ukraine-Russia war, the humanitarian crisis in Palestine, climate change, overpopulation, and the competition between feed, food, and fuel, have pushed global hunger and food insecurity to critical levels. These challenges underscore humanity’s ongoing transgression of planetary boundaries and the overburdening of Earth’s ecological carrying capacity. From an economic and social perspective, we remain far from achieving Pareto efficiency – a state where no individual’s welfare can improve without harming another – and are yet to reach the phases of the Environmental Kuznets Curve where economic growth aligns with environmental regeneration. Acknowledging this gap is vital for developing effective solutions and crafting actionable interventions. The rapid growth of the global population and the rising demand for animal-based products have intensified food security challenges, necessitating transformative changes in current livestock production systems. Limited natural resources exacerbate these challenges, raising concerns about the sustainability of current protein sources for animal feed, many of which have significant environmental and social consequences. Aquaculture and poultry farming, the fastest-growing animal production sectors, rely heavily on protein-rich feed ingredients. Aquaculture, essential for meeting the increasing demand for fish and supporting the 2030 Sustainable Development Goals (SDGs), is highly dependent on fishmeal and fish oil. Despite their nutritional value, the production of these ingredients often involves unsustainable practices such as overfishing, which disrupt marine ecosystems. Similarly, the poultry sector has experienced rapid growth over the past three decades, emerging as a major supplier of animal protein. However, this expansion comes with environmental costs, including habitat degradation, soil and water pollution, and greenhouse gas emissions linked to feed production. The reliance on soybean, a primary poultry feed ingredient, further exacerbates deforestation and ecological concerns. Rabbit farming offers a more sustainable alternative, requiring fewer resources and generating significantly lower greenhouse gas emissions than cattle, pigs, or chickens. As one of the most efficient meat production systems, it aligns well with sustainability and also rabbit meat, a functional food with nutritional benefits, could play a pivotal role in achieving SDGs. However, challenges such as climate change, feed shortages, and economic pressures have raised production costs, underscoring the need for strategies to enhance efficiency and quality. While livestock and aquaculture have environmental impacts, they also provide positive economic, environmental, and social externalities. Managing these sectors sustainably is crucial to preserving their benefits. The principles of the SDGs, circular economy, the European Green Deal, and blue economy must guide current and future efforts. In this sense, addressing these challenges requires the identification of novel, sustainable feed sources. Insects and hemp have emerged as promising alternatives, offering significant potential to enhance resilience and sustainability in animal feeding systems. Insects, particularly larvae, are being studied both for food and feed purposes, since they are rich in protein and lipids and are produced sustainably with high feed conversion efficiency, rapid reproduction, and the ability to utilize organic waste. Their production aligns with circular economy principles by converting waste into valuable resources such as proteins, lipids, and frass (a fertilizer byproduct). For instance, black soldier fly (Hermetia illucens) and yellow mealworm (Tenebrio molitor) larvae exhibit low greenhouse gas emissions and high bioavailability, while queen bee larvae (Apis mellifera) enhance feed quality through their functional properties. Hemp (Cannabis sativa L.), traditionally cultivated for fiber, is gaining recognition as a multipurpose, environmentally friendly crop. Industrial hemp varieties with minimal tetrahydrocannabinol content are widely accepted, and hemp seeds, once considered a byproduct, are now valued for their rich nutritional profile. Hemp contains balanced fatty acids, digestible protein, carbohydrates, vitamins, minerals, and bioactive compounds. Additionally, hemp oil extracted from seeds has applications in pharmaceuticals, dietary supplements, and animal feed. This Ph.D. research investigates the potential of insects and hemp as sustainable feed ingredients and functional ingredients for aquaculture and small terrestrial livestock systems. By evaluating their effects on animal performance, welfare, and product quality, the study contributes to the advancement of sustainable practices in agriculture and livestock production. Four trials were conducted: - Trial 1 regarded the environmental impacts of insect-based feeds in seabream aquaculture. This study assessed three feed formulations for gilthead seabream (Sparus aurata), incorporating poultry by-products, Tenebrio molitor larvae, or Hermetia illucens larvae, compared to a control diet with fishmeal. A life cycle assessment demonstrated the sustainability of insect-based feeds, highlighting their potential to reduce ecological impacts and support aquaculture growth. - Trial 2 focused on the dietary inclusion of Queen Bee Larvae as a functional ingredient in sea bass feed. Apis mellifera ligustica queen bee larvae (QBL), a by-product of royal jelly production, were evaluated as a functional feed ingredient in European sea bass (Dicentrarchus labrax) diets. Inclusion levels of 1%, 2%, and 3% were tested for their effects on growth, liver and intestinehealth, immune status, and fillet quality. Results demonstrated QBL’s potential to enhance health and performance while promoting circular economy principles. - Trial 3 investigated the inclusion of hemp seeds in the diet for medium-growing chickens. Hemp seeds were tested as a sustainable alternative to soybean meal in Naked- neck Kabir chickens, with a 10% inclusion level. The study assessed meat quality, liver characteristics, and oxidative status, confirming hemp’s capacity to maintain nutritional standards in poultry production. - Finally, Trial 4 studied the use of cannabidiol-enriched hemp oil in rabbit feed as a functional addition. Cannabidiol (CBD)-enriched hemp oil was evaluated for its effects on lipid profiles, fatty acid composition, and cholesterol levels in rabbit meat and liver. While results showed minimal changes in lipid content, CBD potential to support health and sustainability in rabbit production systems should be further investigated. In conclusion, this research aimed to underscore the critical role of innovative feed ingredients and additives in addressing global challenges within animal feeding systems. By integrating resilience and sustainability principles, the findings contribute to a more efficient and environmentally friendly livestock sector. As stewards of the Earth, adopting such advancements is essential to ensuring a sustainable future.