Professionals involved in the innovation of animal feeding and forage resource management from 14 countries took part from 8 to 12 May 2023 in an advanced course organized by CIHEAM Zaragoza and the FAO. The training provided science-based advances and applied knowledge regarding the use of alternative and emerging feed and forage resources in the Mediterranean region.
Andrés Schlageter, Administrator of Animal Production and Welfare at CIHEAM Zaragoza and academic coordinator of this course, pointed out that “finding and using alternative feed sources to replace conventional feeds is certainly a step towards sustainable livestock production systems. Relying on emerging, alternative and local feed resources has several advantages when compared to conventional feedstuffs. For instance, emerging, alternative and local feed resources offer a flexible and low-cost option to farmers; locally adapted forage varieties increase agricultural biodiversity, are more resilient to the uncertainties linked to climate change, and have lower carbon and water footprints. Furthermore, feeding animals with by-products reinforces circularity by reducing waste and competition with the food, fibre and fuel industry”.
However, as evidenced during the course, novel feeds can also be challenging for farmers and the feed industry for several reasons. Some issues common to most alternative feed sources are inappropriate nutritional characterization and wide variation in nutrient composition compromising the optimal formulation of diets, lack of regulation to ensure feed safety, and limited supply. Also, sustainable systems relying completely on local and alternative feed sources must be adapted to local geographical, environmental and economic conditions, and therefore sustainable farming systems that work in a specific region could be difficult to export to a different area. Hence, research and extension at local level are needed to implement these sustainable systems successfully.
Drivers of modern animal nutrition
The course addressed the main concepts driving modern animal nutrition. Dr Martin Scholten (Wageningen UR, Aarhus University and SRUC), focused his lecture on circular farming and explained that “circular farming means keeping residuals of agriculture and food-processing within the food system as renewable resources. By wasting less biomass, fewer imports would be needed (i.e. chemical fertilisers and imported feedstuff)”. According to this concept, circular farming cannot exist without livestock production, but livestock production systems must be adapted to the surrounding agricultural systems, food industry and environment.
Dynamic forage systems as a driver of modern animal nutrition was also discussed during the course. This concept, addressed by Dr Giorgio Borriani (University of Torino), implies that it is necessary to stop thinking in terms of growing a single crop, and plan for a forage system, i.e. re-design crop rotation and intercropping systems to develop a more self-sufficient, integrated and closed-loop livestock and plant production system, which is able to secure protein self-sufficiency by increasing the use of crops and by-products. Proper forage conservation methods are essential to secure quality and safety of forages under dynamic forage systems. During his lecture, Dr Angelo Loi (Department of Primary Industries and Regional Development, Australia), explained his successful experience in adapting and growing endemic Mediterranean forage species under the Australian soil and climatic conditions. Currently, Australian farmers are able to grow forage species such as Biserrula and Serradella, that can produce up to 10 t/ha of biomass under semiarid conditions without needing irrigation.
Other lectures about grasslands and rangelands included the utilization of condensed tannins to decrease N emissions in ruminants (Dr Margalida Joy, CITA); forage crops as a valid alternative to feed monogastrics (Dr Javier Alvarez-Rodriguez, University of Lleida); production of barley forage with hydroponic systems in small farms in arid regions (Dr Sourour Abidi, National Institute of Agronomic Research, Tunisia); the problem of erosion in Mediterranean rangelands, the importance of a proper grazing management (Dr Apostolos Kyriazopoulos, Democritus University of Thrace, Greece); and concurrent land use and ecosystem services in rangelands (Dr Isabel Casasús, CITA).
The use of by-products and alternate concentrates
By-products are key to replace conventional feed sources and move forward towards circular farming and feed self-sufficiency. In the course, Dr Luciano Pinotti (University of Milan) explained the advantages of using by-products in animal nutrition including lower prices when compared to conventional feed sources, and good average nutritional quality. However, by-product quality often varies seasonally and between batches. Besides, there may be health issues related to the use of by-products; and technical difficulties may arise when processing uncommon feed resources.
Similarly, Dr David Yáñez (CSIC-EEZ) explained logistics associated to feed by-products with examples ranging from by-products in field and after harvest, silage and pelleting. High water content is one of the main issues for some by-products during transport, feeding and storage. Dr Yáñez also explained how using by-products would decrease the carbon footprint in livestock systems. Finally, Dr Sourour Abidi explained the main by-products from oases used in northern African countries.
Use of alternative concentrates replacing soybean as main protein source in animal nutrition was also addressed by Dr Antonio Natalello (University of Catania) and Dr Mireia Blanco (CITA) during this training activity. Some promising results have been achieved feeding field peas, chickpeas, faba beans and lupin seeds. However, the amount produced of such feeds is not enough to replace soybeans. In addition, alternative concentrate sources contain anti-nutritional factors that decrease animals’ production performance. Many nutritionists, especially those working with monogastrics, discard alternative protein concentrates to avoid production and health issues related to anti-nutritional factors.
Insects and algae, promising feed sources
The last topic of the course was the use of insects and algae in animal nutrition, presented by Dr Pablo Gutierrez-Toral, CSIC-IGM. Both insects and algae are promising feed sources. They have high protein and fat content and high feed conversion efficiency. A disadvantage of using insects at large scale is that insects must be fed with authorized substrates, which are the same as those used to feed livestock. In the case of algae (single cell protein) the disadvantages include poor palatability (compromising feed intake), high production costs and competition with the biofuel industry. For both insect and algae further research is needed to define inclusion rate in diets, define economic and environmental impact of insect and algae farming, and guarantee feed safety.
In general, all the topics addressed during the course highlighted the fact that currently livestock production is going through a change from the dominant paradigm of “maximizing production” to a new paradigm focused on “maximizing sustainability”. This new sustainability-led paradigm is based on several basic concepts such as circular farming, protein self-sufficiency, minimum environmental impact and avoiding competition between feed, food and fuel, among others. However, implementing these concepts under practical conditions is difficult because it requires major changes in livestock production systems and coordinated actions from all the stakeholders involved in the industry.
