Role of Phytogenic Feed Additives in Swine Production- A Review

Continuous research is being carried out to attain higher productivity with the available resources since several decades. Feed additives comprising of probiotics, prebiotics, acidifiers, immune modulators, buffering agents, ionophores etc. though are in vogue,in addition to antibiotic growth promoters(AGP), advancement is being aspired through the way of herbs and their products which are called as Phytogenic feed Additives (PFA) or simply Phytobiotics. PFA are said to be having positive effects in improving the performance of poultry and swine. Many reports say that PFA increase the dry matter intake probably due to an increased palatability of the feed.PFA is said to have anti microbial and anti oxidant properties. In addition, PFA have shown to improve the endogenous enzyme secretion, stimulation of appetite, improving the digestibility and absorption of nutrients and also promote the proliferation of beneficial bacteria like Lactobacillus spp. A ban on the use of AGP leads to explore the use of herbs and their products like extracts and residues. Herbal residues are the left over's remained after the active principle is extracted. Reports say that extraction efficiency (%) ranges from 88-97 for different methods. Some of the residues showed considerable anti bacterial property at 2% levels during the Minimum Inhibitory Concentration tests. The use of PFA is restricted to commercial preparations and results are available only for these works, there needs a systemic approach to explain about the function of these PFA in terms of type and dose of each additive. However long term studies will be of added advantage proving the efficacy of these PFA,their safety for animal health and their availability widely in nature. The aim of this review is to explore and explain the multifaceted properties of PFA in terms of elimination of gut pathogens improving the digestibility and palatability and thus enhancing the overall production of the animal.