Article
www.pixie.co.in
Role of Essential Oils in Poultry Nutrition Ankit Sharma, Amitav Bhattacharyya, P.K. Shukla and Vaibhav Kr. Singh Department of Poultry Science, DUVASU, Mathura (U.P.), India
Essential oils (EOs) are obtained as a mixture of aromatic oily liquids from plant materials such as leaves, flowers, buds, seeds, twigs, bark, wood, herbs, fruits and roots. In fact, essential oil is a mixture of fragrant, volatile substances and named according to the aromatic characteristics of plant materials from which they are isolated (Oyen and Dung, 1999). Their concentrations and chemical composition of individual compounds are variable. They are obtained by methods like fermentation, extraction or expression, but the most commonly commercially used method is steam distillation (Krishan, 2014). Various EOs used in poultry include oils from oregano (Origanum vulgare), onion (Allium cepa), turmeric (Curcuma longa), lemon balm (Melissa officinalis), peppermint (Mentha piperita), rosemary (Rosmarinus officinalis), sage (Salvia officinalis), cinnamon (Cinnamomum zeylanicum), thyme (Thymus vulgaris), ginger (Zingiber officinale), eucalyptus (Eucalyptus globulus), garlic (Allium sativum), clove (Syzygium aromaticum), fennel (Foeniculum vulgare), mountain savory (Satureja montana), Australian tea tree (Melaleuca alternifolia) and mugwort (Artemisia vulgaris) (Bolukbai et al., 2008). EOs can be classified into the four main groups 1. Terpenes, related to isoprene:Essential oils constituents can be divided into two major groups: terpene hydrocarbons and oxygenated compounds 2. St r a i g h t - c h a i n c o m p o u n d s n o t containing any side chain 3. Phenylpropanoids (benzene derivatives) 4. Miscellaneous group having varied structures not included in first three groups (sulfur or nitrogen-containing compounds). Benefits of essential oil in poulty
08
Growth Sahar Abdulhasan (2018) studied the positive effects of two different commercial products (Digestrom® and Poultry Star®) on body performance and the immune response in broiler. Digestrom® contains a blend of oregano, anise and citrus peel essential oils 150 mg/kg of the diet. Carvacrol is the active and main compound of the essential oil blend. Poultry Star® is an Australian product made from a mixture of beneficial bacterial isolates including lactic acid bacteria as well as a mixture of Enterococcus spp., Bifidobacterium spp., Pediococcus spp., Lactobacillus spp. for 2×1011 CFU per kg of probiotics. Supplementation of Digestrom® @ 150 ppm in the diet resulted in improved body performance and increased serum total protein levels. Moreover, both individual and combined application of Digestrom® and Poultry Star® increased the immune response against New Castle Disease virus, with synergistic effects observed with combined treatment. Supplemented with thyme EO @100mg/kg resulted in significantly improved FCR, higher body weight gain, livability and profit in broiler production (Wade et al., 2018). There was improvement in growth performance of live broilers when fed with EOs mixture of 200 ppm of anise oil, oregano, clove, rosmarin and turmeric plant (Al–Sultan Zhang et al., 2003). When essential oil mixture @24 and 48 mg/kg diet were fed to broilers, then there was better feed conversion ratio. EOs increase appetite due to their flavours which is very important for young animal to grow. Essential oils stimulate the secretion of digestive enzymes leading to improved nutrient digestion, feed intake and rate of gut passage (Jamroz et al., 2005). The beneficial impact of essential oils is interlinked with health and immunity due to change of gut microbiota and it will affect growth performance and welfare (Bento et al., 2013). There was improved feed
efficiency when thyme EOs was fed to broiler quails (Denli et al., 2004). Essential oils in diet may act on intestinal microflora as well as on nutrient utilization (Bento et al., 2013). Egg Production EOs supplemented in the diet of layer increase eggshell thickness and protein digestibility but there was no significant effect on performance and yolk fatty acid composition. Overall EO at the low dose of 50 mg/kg in diet of layer may be beneficial (Ding et al., 2017). When thymol and synbiotic were supplemented separately as well as combined, there was improvement in egg weight, egg production and FCR from 24 to 36 weeks of age (Abdel-Wareth et al., 2016). Supplementation of garlic powder in the diet of the layers leads to increased egg production (Canogullari et al., 2010) and increased egg weight (Yalcin et al., 2006). Supplementation of a diet with a mixture of garlic and thyme leads to improving performance of laying hens and egg quality traits (Ghasemi et al., 2010). Under heat stress, EO mixture and organic acid supplementation in commercial layer diets is beneficial to egg weight and immune function (Ozek, 2011). Supplementation of EO mixture at the level of 24 mg/kg diet significantly improved egg production reduced the percentage of cracked/broken eggs, increased feed effeciency (Cabuk et al., 2006b). Deying et al. (2005) reported supplementation of herbal medicine (Ligustrum lucidum and Schisandra chinensis) in diet significantly improved egg production and feed efficiency of layers. Antimicrobial activity Essential oils have known for their antimicrobial activity (Smithpalmer et al., 1998). The antimicrobial properties are due to cumulative effect on many different targets in various parts of the cell and not because of one specific mode of action of the chemical compounds present in EOs (Burt, 2004). The exact anti-microbial mechanism of EOs is their chemical structure and lipophilic quality. Terpenoids and phenyl propanoids Poultry Planner | Vol. 22 | No.08 | October - 2020
