India has evidenced tremendous growth in Poultry Industry in terms of both broiler meat production and egg numbers. There have been huge developments in terms of genetics of bird and its nutritional requirements and managemental practices. Various technologies pertaining to nutrition and management and feed additive concepts have been adopted by poultry producers that consequently have led to better productive performances of birds. With backward integration practices very strong in India, the forward integration in terms of processing and value-added products is also gaining momentum due to changing lifestyle, consumer awareness, increasing income, changing eating habits of consumers etc. In this context, keeping in mind “safe farm to fork concept”, it is the responsibility of the poultry producer to produce a safe and hygienic food to consumer. Thus, with the famous notion quoting – “You are what you eat” – the poultry feed produced needs to be safe for the final chicken meat/egg been produced, to be safe enough to be consumed by the consumer.
Of the various feed additives used to safeguard the health of birds, antibiotic growth promoters (AGPs) are one that have been used since decades in Indian Poultry industry.
AGPs
Antibiotics as the name implies are antimicrobial drugs used in the treatment and prevention of bacterial infections. In feed AGPs are the antibiotics that are used in smaller doses throughout the lifecycle of birds or for a certain duration (like week a month program in layers and breeders) for the prevention of bacterial infections. The antibiotics supposedly, depending on the type been used eitherto kill or inhibit the growth and multiplication of bacteria, thereby promoting better health and performance of birds. As there are two sides to every coin, misuse/abuse of in feed AGPs can act as a bane rather than a boon. There are various ill-effects associated with the irrational use of AGPs, with the major been,
Antimicrobial resistance (AMR)
AMR is the resistance developed by microbes towards an antibiotic, failing the ability of antibiotic to treat a specific condition, leading to persistence of infection and its further spread.
- AMR has been a burning threat world-wide, questioning the effectiveness of antibiotic usage and treatment in animals and humans.
- Accumulation of antibiotic residues in meat tissues can lead to further potential AMR.
- Also, the antibiotics may cause destruction of normalmicroflora of gut (beneficial bacteria), disturbs the normal gut morphology, leading to the thickening of gut epithelium etc.
The resistance can be developed through many ways, as detailed in Fig. 1,
- The microbe can acquire gene encoding enzymes that destroy the antibiotic (such as Beta Lactamase)
- The microbe can acquire efflux pumps that push the antibiotic out of the cell before its effect is elicited
- The microbe can acquire several genes that bring about a modification of their exterior cell wall so that the antibiotic cannot adhere to the cell wall to show its effect
- The microbe can undergo mutation to limit access of antibiotic
- The microbe can acquire genetic information from other microbe that is carrying resistant gene (through plasmids) through transformation, conjugation or transduction. By this way, the microbe become resistant to multiple class of antibiotics, causing huge public health concern.
The antibiotic resistant bacteria can spread between animals and humans directly or indirectly through environment and from person to person.
With this been said, AMR can be caused due to a multitude of reasons, varies from country to country and is often very difficult and confusing to pin point to a single etiology. The major causes of AMR are – Improper course of antibiotic (humans/animals not taking the antibiotics for a specified period), self-medication in humans, OTC sale of antibiotics for human, indiscriminate use of antibiotics in humans/animals, poor hygiene & sanitation etc.
Irrational use of antibiotics (including in feed AGPs) in animals may lead to resistance of microbes to antibiotics, and the accumulation of these antibiotics in tissues, which in turn might lead to antimicrobial resistance in humans when this animal produce is been consumed by humans. So, due emphasis should be placed on the prudent use of antibiotics in animals.
Limitation on the use of Antibiotics
Following the limitations of antibiotics and the rising awareness of associated human health risk concerns due to AMR, many countries have imposed ban on in-feed AGPs, as mentioned in Table 1 below, In 2015, the US introduced the veterinary feed directive whereby the use of drugs on the veterinary feed directive list are permitted only under the professional supervision of a licensed veterinarian.
India has always been in the radar with respect to use of antimicrobials in poultry industry. The global consumption of antimicrobials in animals was estimated to be 63,151 (±1,560) units in 2010; of which India accounted for 3% of the global consumption and is the fourth highest in the world, behind China (23%), the United States (13%) and Brazil (9%). The consumption of antimicrobials in the food animals sector in India is expected to double by 2030. In a recent survey by Ramanan Laxminarayan, Director of the Center for Disease Dynamics, Economics & Policy, Washington DC & New Delhi, it was found that the prevalence of multiple-drug resistant bacteria was 94% in broiler farms as opposed to 60% in layer farms. Prevalence of ESBL positive bacteria in broiler farms was also higher at 87% vs. 42% among layers.
Policies & Regulations in India
Currently, there has been no stringent legal policy with respect to limitation of use of AGPs in animals, though, in the past, there had been many directions passed with respect to the stoppage of usage of antibiotics in animal feed. In 2014, the Drug Controller General of India and agriculture ministry directed the state government to stop the use of antibiotics in animal feed.
A directive was issued in January 2015, by the FSSAI which outlines certain principles that include limiting the use of antibiotics in livestock rearing. However, there has been no mention of a roadmap or implementation plan, making it difficult to execute and monitor. A recent directive passed by FSSAI focusses on antibiotic ban in India by Jan 2019.
Way forward
With the increasing consumer awareness and the demand for quality residue-free products, it becomes crucial for the poultry producer to practice and adopt technologies and concepts that produce a safe and hygienic food. Import of US legs into India, further places stress upon the quality of local chicken produced and marketed in India. This calls for judicious use of feed additives.
For an antibiotic-free poultry production, a step-wise and holistic approach needs to be adopted.
- The usage of in-feed AGPs should be curtailed step-wise. For e.g.; Reducing from a multi AGP usage to a single AGP; cutting down of AGP in different phases – usage in pre-starter & starter diets but not in finisher etc.
- Use of gut health promoting concepts like organic acids, probiotics, prebiotics, enzymes etc.
- Use of immune boosters like biological antioxidants, Vitamin E, Vitamin C, Selenium, carotenoids, Beta-glucans etc.
- Use of sterilized animal protein and good quality raw materials.
- Improved management practices.
- Improved biosecurity and vaccination schedule.
- Improved water quality.
- Surveillance of antibiotic use.
- Usage of antibiotics for therapeutic purpose under the supervision of Veterinarian
There are various gut health promoting concepts that aid in improving the gut morphology, microbiota and overall integrity consequently improving the performance of birds. The concepts that are proven to work in this segment are Short Chain Fatty Acids (SCFA), Medium Chain Fatty Acids (MCFA), a combination of SCFA and MCFA, polyphenols, prebiotics, probiotics, essential oils, enzymes and phytase. The gut health program varies from customer to customer and have to be customized depending on the customer requirement.
Conclusions
Reducing the use of in-feed antibiotics in poultry feed and moving towards an antibiotic-free production, will not only minimize the AMR risk but also in parallel enhance the quality of chicken meat been produced, increasing the efficiency of poultry production and profitability. Best practices need to be adopted in the entire poultry production chain, right from breeder flock until processing chain.
Trouw Nutrition is committed to assist poultry producers with their gut health program that encompasses detailed analysis of the critical control points in the poultry production chain and to provide customized solutions according to the situation.
For further discussion the author can be contacted at sabiha.kadari@trouwnutrition.com
by Dr. Sabiha Kadari,Trouw Nutrition India
