The Impacts of Vegetables and Fruits by Products on Growth and Health of Broiler Chickens

Agro-industrial by-products, which are not intended for human consumption, can serve as substitutes for traditional animal feed ingredients in animal nutrition. This can result in the production of animal products without causing competition for land or exacerbating the food versus feed dilemma, ultimately promoting environmental and economic sustainability. Utilizing co-products as animal feed has the potential to reduce feeding costs while enhancing the productive parameters, quality, animal welfare and sustainability of animal products. Numerous studies have indicated that fruits and vegetables are considered as significant sources of bioactive compounds. The extensive process of industrialization leads to the creation of considerable amounts of by-products, giving rise to grave ecological concerns. Hence, such a scenario necessitates the formulation of innovative approaches for effectively utilizing the resultant wastes, ensuring the potential to fabricate novel products with enhanced value. The generated by-products, reveal similar or higher antioxidant activity. It is recognized that these secondary products comprise various bioactive substances and may have the ability to serve as nutraceuticals for poultry, promoting their health and overall wellness. This review aims to summarize the exploitation of fruit wastes, namely, apple, citrus, banana, mango, pineapple and grape as well as vegetable by-products which are derived from tomato and olive cultivation. These byproducts can be in supplementation or substitution format. Some of these byproducts presented the following results: The addition of 2% dried sweet orange pulp to the diet significantly increased feed intake and total weight gain in broilers and the inclusion of dried orange pulp in broiler diets was found to reduce serum triglycerides and cholesterol. Also, the including of 10% apple peel in the diet led to an increase in the weight of the gizzard and small intestine in chickens. Additionally, diets containing 5% and 10% apple peel waste resulted in higher levels of lipids and HDL (high-density lipoprotein) in the blood serum, while LDL (low-density lipoprotein) and malondialdehyde levels decreased. Moreover, the including of 10% banana peel in poultry feed led to improved feed efficiency, feed conversion and the quality of poultry eggs and meat. However, the inclusion of olive cake with phytase to broiler chickens’ diet presented an increase of growth parameters increased. The incorporation of 10% of OC with phytase also resulted a reduction in plasma cholesterol and triglycerides and an increase in plasma inorganic phosphorus.