Dr. Pratik R. Jadhav*, Dr. Gajanan V. Langote, Dr. Akash V. Raut
The availability and cost of soybean meal, a prime source of dietary protein which is a major constraint in practical feed formulations. In order to reduce cost of poultry production and to cushion the shortage of de-oiled soybean meal, there is urgent need to search newer alternate protein feedstuffs and to explore their usefulness for poultry feeding. Mushroom waste is a very good source of protein, available energy, critical amino acid like methionine and bioactive substances having medicinal value. The Food and Agriculture Organization (FAO) of the United Nations has recognized mushroom as a product that contribute to feeding those parts of the world which depend largely on cereal diets. In mushroom farming, huge amount of damaged, small and deformed mushrooms as waste are obtained. The edible mushrooms have antioxidant, immuno-stimulatory, anti-inflammatory and antibacterial properties. It is also helpful in reducing cholesterol. Hence, there is a need to inclusion of its optimum dietary level and use its feeding value in broiler chickens.
Button mushroom (Agaricus bisporus), Paddy straw mushroom (Velvariella volvacea) and Oyster mushroom (Pleurotus ostreatus) are the three most popular varieties of mushrooms for commercial cultivation. The proteins in mushroom are comparable to muscle protein in nutritive value and it contains about nine essential amino acids. They are richer in protein than any comparable fruit or vegetable and also rich in vitamins like ascorbic acid, folic acid, niacin, pyridoxine, riboflavin, thiamine and α-tocopherol. Mushrooms are considered as valuable health foods all over the world as they are poor in calories, fat and rich in proteins, vitamins and minerals. Mushrooms also contain anti-cancerous compounds like polysaccharides viz. lentinan, beta glucan, lectin and thioproline. Mushrooms have been well known to have antibacterial property as the poultry industry has been challenged to stop antibiotic growth promoters as it develop resistance, mushrooms could be a potential substitutes. Some fungi have been used to combat disease outbreaks in many countries for centuries and are still being used in ethno veterinary medicine. Mushrooms may have a wide range of activities. The extracts derived from various mushrooms have antioxidant, antibacterial, immune-enhancing, and stress reduction properties on farm animals. Recently, it has also been reported that the combined use of Chinese herbal and mushroom extracts can be used as an alternative to antibiotic growth promoters in broiler chicken.
Ergothioneine has been identified in mushrooms as the main antioxidant compound, whereas, the phenolic antioxidants, variegatic acid and dibiviquinone are also found in mushrooms. Antioxidant activity of mushrooms has been documented in-vitro as a radical activity scavenger and in vivo as a cellular protector against oxidative damage in liver microsomes. However, there is no evidence as to whether dietary supplementation of dried mushrooms can improve oxidative stability of chicken tissues. Agaricus bisporus mushroom is also considered as a good source of selenium. Consumption of A. bisporus, which is the most widely investigated edible mushroom, has been shown to retard the development of free radicals. On this basis, it may be clear that inclusion of A. bisporus mushroom have growth promoting as well as antioxidant effects on poultry meat.
Cell walls of mushrooms contain a high number of polysaccharides known as β-glucan, derived from the fruiting bodies of mushroom. Both in-vitro and in-vivo studies demonstrate that 1-3 and 1-6 glucan promote immune enhancement. These effects are achieved by activating macrophages, T-helper and natural killer cells that also involved in the differentiation and proliferation of T-lymphocytes.
The addition of mushroom in poultry feeds found to improved growth performance in poultry. Many scientist reported that adding mushroom to broiler diet improved feed conversion ratio but not body weight gain. Mushroom also contains considerable amounts of oligosaccharides, which have beneficial effects on the growth performance of broiler chickens. It seems that the mechanism of action of fungi is similar to that of probiotic because fungi possess medicinal properties that can improve gastrointestinal function, which is due to the presence of polysaccharide compounds in the fungi. The methanol extract derived from mushrooms can eliminate free radicals because of an antioxidant property of mushrooms due to presence of phenolic compounds. Furthermore, the authors found that the extract stimulated the number of the potentially beneficial bacteria (bifidobacteria and lactobacilli) and reduced the harmful bacteria like Bacteroides spp. and Escherichia coli. As it has low fat and energy content it may promote quality lean meat beneficial for health of chicken consumers.
Keeping this in view, mushroom waste can be a rich source of protein in poultry feed and their many nutraceuticals values shows that it can be better unconventional alternative source in poultry sector.
