Dr.G.Karthikeya Head-Technical-Provet Pharama Pvt Ltd
Performances of Modern Poultry Production are improving day by day, thanks to Biotechnology, which has gained inroads into Poultry Nutrition. Subsequent to the banning of antibiotics as feed additives in many countries, many biotechnological products have been important feed additives in boosting the performances of broiler birds. Nowadays FCR from 1.9/2.0 to 1.5/1.6 is not a distant objective. Even the breeders and commercial layers have shown consistent improved performances over the years.
Salmonellosis, Camphylobacteriosis and Coilbacillosis are very important disease, which affects the performances of poultry. Salmonella and Camphylobacteria infection in poultry are a constant threat to humans .To counteract these challenges and to have improved performances, many producers uses growth promoters either single or in combination.
Antibiotics and other chemotherapeutics in prophylactic doses were used as feed additives in poultry mainly for economical benefits like fattening of birds, better production, lesser mortality, improved performances and reduced medicinal cost.
Broad spectrum antibiotic feed additives like Tetracycline compounds have been regularly used, which has proven to control the growth of variety of Gram positive and Gram negative bacteria. Narrow spectrum antibiotics were used to control specific bacterial infections. Gut acting antibiotics like Bactracin, Virginamycin, and Enramycin etc and anti Coccidial drugs have been used legimately to improve gut health integrity.
Patrick et al (2003) postulates their mode of action may be due to
1. Nutrients would be protected against bacterial destruction.
2. Absorption of nutrients may improve due to thinning of intestinal barrier.
3. Antibiotics may decrease the production of bacterial toxins in the intestine.
4. Reduction in incidence of Subclinical intestinal infection.
However continuous use of antibiotics at prophylactic and treatment dose have increased the risk of developing cross resistant and multiple antibiotic resistant pathogenic bacteria, which possess a great threat to health of Humans and Livestock. Many countries have banned usage of antibiotics as feed additives, which paved the way for other growth promoters.
Enzymes were added routinely in poultry feed mainly
1. To breakdown certain components in feed, which otherwise not easily digested by poultry enzymes of which majority are lacking.
2. For proper utilisation of feeds of poorer nutritive value.
3. To prevent environmental pollution.
Increase in 10% performance over the control group has been narrated by Owreson et al 2000.However positive effects on performances depends on quantity and quality of feed stuffs, level and type of enzyme used and condition of the birds(Lukic et al 2002).Mixture of enzyme concept were used regularly for increasing the efficiency of performances. However Proteases and Mannases concept is gaining popularity because of usage of unconventional feed stuffs. New enzyme combination and their optimal dose are constantly analysed for improved performances.
Organic acids reduces the pH value of feed, thereby discourages the growth of bacterial, moulds, fungi. Acidifiers acts as a conserving agent, prevents bacterial/mould contamination and to maintain good intestinal integrity. Supplementation of single (Formic, Fumaric)to mixture of organic acids has been established for favourable effects on improved feed consumption, better FCR, increased body weight and better production.
Organic acids may also have negative effects in poultry, as it alters the normal bacterial floral population in the gut, corrosive nature to humans and equipments. Hence careful selection of organic acids, their combination and dose must be taken due care into consideration.
Oxidation in feed/raw materials results in rancidity of fats, destruction of Vitamins A, D & E, depigementation of cartenoids, and losing biological value of amino acids (Biogenic amines) resulting in poorer performances. Selection of antioxidant should be based on how effectiveness in preserving fats/oil, vitamins and amino acids. It should be non toxic to humans and livestock, should be effective at lower concentration and should be economical.Commonly used antioxidant are Ethoxyquim, BHA (Butylated hydroxyanisole) and BHT (Butylated hydroxytoulene).However numerous chemicals are also been used as preservatives in feeds, But their efficacy should be studied in details.
Phytobiotics are substances derived from plants which used to augument the performances of birds. In phytobiotics, whole plant or part of the plant or oil derivatives is used. They also exhibit antibacterial, antiviral and antioxidant properties. Scientist had both views on positive and negative effects on performances of birds, But Yang et al(2009) correlated performance depends on type of plant used and their physical properties, Time of harvest of plant, Preparation methods and Compatibility with other nutrients. But health condition, environment and genetics of birds also to be known, to study the effects of performances.
6. Probiotics/Direct Fed Microbials (DFM):
Probiotics are preparations of intestinal microflora, applied in feed in the form of live cells or spores or yeast to aids in growth of birds. Usually probiotics contains Bacillus, Enterococcus, Lactobacillus or Saccharomyces.
Probiotics acts in two ways either by competitive exclusion(CE) mechanism, wherein probiotic bacteria proliferates in GI tract, competes with space and food of pathogenic bacteria and produces substances like short chain fatty acids(Lactic, acetic, propionic) ,bacteriocins (Nisin, acidolins, acidofilina etc) and hydrogen peroxide or by stimulating the efficiency of immune system.
Prebiotics are non-digestible dietary components, selectively stimulate the growth/activity of one or limited number of probiotic bacteria in the gut(Manning and Gibson,2004).Advantages of using over the probiotics is that, they promotes growth of useful bacteria like bifidobacteria and lactobacillus and adapts to all ph ranges in the gut(Yang et al 2009).Prebiotics also acts as a source of carbon atoms to probiotic bacteria in the intestine. Numerous prebiotics are available in market are of derived from either plant source or yeast source. Fructooligosaccharides (FOS), Mannanoligosaccharides
(MOS), Xylooligosaccharides (XOS), Inulin etc are used frequently as perbiotics in feed.
Prebiotics acts by 1.lowering the gut pH through lactic acid production (Gibson&Wang,1994)
2. Inhibiting/Preventing colonisation of pathogens (Morgan et al 1992)
3. Modifying metabolic activity of normal intestinal flora (Demigne et al 1986)
4. Stimulation of Immune system (Monsan & Paul 1995)
Synbiotics are combination of probiotics and prebiotics which had significant improvement in bird performances. Many technical articles shows an increased performances, but combination of prebiotics with single probiotic bacteria or multiple of probiotic bacteria, dose and economical cost to be studied in detail.
Increased feed cost and high environmental challengers have been a constant threat to poultry industry. Poultry producers have reduced the dietary protein levels due to increased protein prices, and were forced to use many unconventional raw materials, leading to alteration in physiology of gut, thus favouring opportunistic pathogens to colonise in the intestine.
Constant environmental challengers, climatic stress have also had its impact on poultry production. Nutrionist and Health persons are in desperate to use growth promoters either in single or in combination, which can bring out good intestinal integrity, prevent bacterial colonisation in intestine, increase efficacy of immunity and preventing damages to intestine and lymphoid organs by mycotoxins.
® a prebiotic having thickest cell wall of yeast having MOS and Beta glucans had proven records of pathogen agglutination, increasing non specific immunity and neutralising mycotoxins in feed.
References: Available on request