In “Natural is future 2.0” – the webinar series hosted by Natural Remedies Pvt. Ltd., the September webinar was moderated by Dr. Chandan Chatterjee, Group Product Manager where eminent poultry scientist, Dr. S. V. Rama Rao conveyed his valuable speech on the topic “Dietary modulation for better feed efficiency”.

Natural Remedies Pvt. Ltd. is India’s number one herbal veterinary health care company growing globally in 30 countries under leadership of Mr. R. K. Agarwal, Chairman and Mr. Anurag Agarwal, MD & CEO. It brings solutions in terms of the health products for all species like ruminant, poultry, aqua and pets. We have world class R&D laboratory located in Bangalore where more than 40 scientists are working hard and have contributed in isolation of over 220 phytocompounds and published more than 100 monographs, 120 scientific articles in peer reviewed journals and over 15 patents. We have GLP certified in vitro laboratory for safety studies and we maintain the consistency of our product batch after batch.

The company organizes the webinar series Natural is future 2.0, where national and international renowned speakers deliver their speech related to animal and poultry health.

Dr. S. V. Rama Rao focused on the importance of diet of poultry birds to improve their feed efficiency. He began his talk with briefing the chicken intestine and its functions. He discussed that the gut of the poultry birds has the vital role in conversion of feed to egg as well as body mass.

The layer birds can convert 110 gm of feed into 48 gm of egg mass, whereas, the broilers consume 3.5 to 4 kg feed in 40 to 42 days to gain body weight of around 2.5 to 2.7 kg. Anatomically the digestive system of poultry bird consists of esophagus, proventriculus, gizzard, duodenum, jejunum, cecum, colon, rectum and vent. The gut has dual role in digestion as well as in preventing entry of pathogens by acting as a protective barrier. The complex food materials are digested, dissimilated and absorbed into simple substances like glucose, amino acids, and fatty acids. The immune-components of the gut system of chicken consist of bursa of fabricius, caecal tonsils, meckel’s diverticulum, payer’s patches and epithelial lymphocytes which have major role in protection barrier. Hence, it can be inferred that the birds with healthy intestine exert good immune system and superior health condition.

Dr. S. V. Rama Rao pointed out that the lower feed efficiency is due to the imbalanced diet, contaminated feed with mycotoxins and pesticides, pathogens and also the poor water quality and environmental stress. The typical poultry diet consists of maize & cereals of 50 to 65%, SBM & oilseed cakes of 25 to 40% and additives of 5 to 12%. The non-starch polysaccharide (NSP) is considered as anti-nutritional factor for poultry birds causing detrimental effect on nutrient digestion and absorption, increasing energy requirement for maintenance of gut and developing necrotic enteritis.

After narrating the gut anatomy and physiology of poultry birds, he initiated his elaborative discussion on the focused area like easy food, gut potentiates, inert fibre, enzymes and various stressors.

Easy food

Easily digestible food is also called baby food. It is known that hydrolysable protein is having higher digestibility than conventional protein. Hence, feed supplemented with 5 or 10% of hydrolysable protein from soyabean meal improves the feed efficiency among the birds.

Emulsifier

Most of the studies show that addition of emulsifier to the poultry feed has a positive impact. In one of the studies, emulsifier showed progressive increase in feed efficiency as compared to control. It was found that addition of emulsifier at the level of 300 gm per ton of feed develop 1.668 food conversion ratio (FCR) whereas, the birds of control group show FCR of 1.697.

Effect of bile salt on FCR of birds

Bile salt has an important role in increasing the feed efficiency in poultry birds. One study showed that each ton poultry feed supplemented with 10 kg of bile salt improved the feed efficiency significantly. The study data revealed the FCR of 1.56 in test group in comparison of the control group showing FCR of 1.5888.

Marygold phenols and leutein can be used as an alternative to antibiotic growth promoter (AGP). They reveal significant improvement of feed efficiency as compared to the positive and negative control groups where feed supplemented with or without AGP.

Gut potentiates

Probiotics: Probiotics are live organisms which are beneficial for the gut of the birds and helps in maintaining healthy gut system with higher feed digestibility. In one of the study it was found that the addition of probiotics at the rate of 600, 1200 and 1600 million CFU per kg of feed revealed the FCR of 1.693, 1.705 and 1.654 respectively.

Now a days bacteriophage treatment in feed is gaining popularity in poultry industry as it has beneficial effect in digestibility. The dose rate at 1 x 10 6 PFU/ bird in drinking water showed better feed efficiency among the birds.

Na-butyrate as alternative to antibiotic growth promoter

Na butyrate has a potential impact in improving feed efficiency among birds. Na butyrate is dissociated into butyric acid at the lower intestine which promotes acid environment and prevents the growth of the harmful bacteria. Some studies showed that the use of betaine could increase the feed efficiency in birds.

Inert fibre

There are some oligosaccharides helpful for the growth of beneficial microorganisms in the gut. It was observed that addition of 250 gm/ton of GOS in broiler feed led to lower FCR of 1.56 as compared to the birds of control group. However, the optimum dose of the inert fibre is the most important to gain maximum feed efficiency in broilers.

Pure fibre supplementation

The supplementation of pure fibre in poultry diet is essential when the dietary fibre level is below 3% to improve the feed efficiency in birds.

Natural fibre

Supplementation of natural fibre like rice husk, soya husk or groundnut husk shows consistent improvement of feed efficiency in broiler birds.

Enzymes

Dr. Rama Rao narrated that there are 3 types of enzymes viz. phytase, NSP enzymes and protease having potential impact in poultry diet. Phytase superdosing has a significant effect on body weight leading to >6.5 unit of feed efficiency. Although, it should be performed in a neutral pH environment of 6.5 to 7.0 for obtaining optimum result. Moreover, combination of phytase with inositol improves the feed efficiency among birds. Cocktail enzymes as well as enzymes in combination of probiotics significantly improve the feed efficiency and body weight in broiler birds. We can remarkably reduce the FCR after using the cocktail enzymes. In case of layer birds cocktail enzymes help to save around 4.5g feed per egg. Supplementation of xylanase enzyme is also important in improving the feed efficiency, however, higher levels of xylanase i.e. more than 600 unit/kg is also detrimental. Supplementation of alpha galactosidase in feed improves FCR by 6 units.

Papain

Supplementation of papain at a rate of 1000 gm per ton of feed had shown improvement in body weight gain of the broiler birds as well as feed efficiency as compare to the control group.

Summer stress management

Dr. Rama Rao elaborated that in summer season the feed intake as well as feed efficiency fall drastically. Addition of guanidinoacetic acid (GAA) during summer season at the rate of 600g and 800g per ton of feed improves the FCR of the birds and shows positive impact in reducing heat stress. Betaine is another feed additive which helps to increase the feed efficiency by approximately 6 units per bird in the summer season. It regulates the osmolaritic tension of the cells and retains the minimum water level required for normal functioning of the cells.

Dr. Rama Rao concluded that supplementation of poultry diet with feed additives like emulsifiers, bile salts, enzymes and probiotics helps to improve the FCR and ultimately saves the feeding cost which is beneficial to the poultry farmers.

The questions addressed during the session are as follows:

Explain the synergistic effect of various supplements in increasing feed efficiency?
Dr. Rama Rao: There are feed supplements which show synergistic response at gut level and improve feed efficiency e.g. NSP enzymes and probiotics. However, not all substance will show the synergistic effect at gut level.

How to enhance caecal microbial fermentation and what will be its direct impact?
Dr. Rama Rao: Strategic targeted delivery of butyric acid, essential oil and probiotics directly at the posterior part of the intestine or caecum helps to reduce the pathogenic bacteria population like Clostridium spp. and enhances feed efficiency.

Does betaine hydrochloride show similar effect like anhydrous betaine in osmoregulation and thermoregulation?
Dr. Rama Rao: Betaine is naturally better adapted in the cellular level of biological system. However, higher concentration of betaine hydrochloride or sulphate may have some negative impact. Betaine anhydrous is adapted well by the cells.

How beneficial are the phytogenic compounds in improving feed efficiency?
Dr. Rama Rao: Marygold phenols and leutein show good results as compared to AGP in chickens. So the phytogenic additive can be beneficially used without any side effect as these are derived from natural sources.

High energy low protein or high protein low energy which diet is recommended?
Dr. Rama Rao: We need to provide a balanced energy and protein diet to the birds. They should not be less than the recommended level in diet.

Are there any incompatibilities among the feed ingredients to be considered while formulating the feed? Does any ingredient show antagonist effect with choline chloride present in feed?
Dr. Rama Rao: The choline is very much hygroscopic material. It may interfere with some nutrients like amino acids, vitamins and trace minerals antagonistically. So, choline chloride should be added separately to protect the food ingredients which are oxidative in nature.

Can we use higher dose of Na-butyrate or enzyme to improve absorption of multiple ingredient diet used for commercial layer?
Dr. Rama Rao: All macro or micro nutrients should be provided only at optimum recommended doses. However, super dosing of Na-butyrate may have beneficial effect.

Can feed additives with immunomodulating property enhance feed efficiency?
Dr. Rama Rao: The compounds which help to improve gut development and function, can definitely improve the feed efficiency. However, the feed efficiency can be improved up to the genetic potential of bird not beyond that.

Is there any way to improve feed efficiency at the cellular level?
Dr. Rama Rao: There are many literatures available regarding this topic, but more trails and investigations are required.

Is it possible to have 1:1 FCR in case of present breed?
Dr. Rama Rao: Theoretically it may be possible when there is 100% digestibility and assimilation of the feed achieved in genetically modified birds with improved feed efficiency. However, in reality there are some physiological limitations which prevent to achieve this goal.

Contributed By: Dr Raina Raj, Head of Marketing, Natural Remedies Pvt. Ltd

Natural is future 2.0 is a webinar series powered by Natural Remedies Pvt. Ltd., where we invite eminent speakers from across the globe to share their thoughts on the most relevant topics in the animal health industry.

In August, we had the privilege of hosting two speakers, Dr. Sudheer B. Rukadikar, Veterinary Pathologist and Poultry Health Consultant, and Dr. Chandan Chatterjee, Group Product Manager at Natural Remedies Pvt. Ltd. The focus of their discussion was towards understanding and providing practical solutions to the respiratory challenges in poultry, faced during high humidity conditions.

Dr. Rukadikar started his talk by pointing out the increased incidence of respiratory diseases worldwide in recent days due to the intensive rearing methods followed. He has used the term respiratory disease complex (RDC) as acute respiratory diseases caused due to several etiologies characterized by respiratory distress, depression, and increased mortality in poultry.

Dr. Rukadikar mentioned that each year, India faces losses of millions of rupees due to poultry sickness caused by viruses, bacteria, and fungi. Microbial illnesses in poultry are a huge concern, despite the widespread use of antibiotics and the best vaccinations available. The large bioburden is one of the explanations. Bioburden is the presence of disease-causing organisms in the shed, which are passed down from one flock to the next.

Dr. Rukadikar brought to notice that there has been growing concern about the presence of residual antibiotics in poultry meat in recent years. This puts pressure on poultry rearing practices to limit antibiotic use in poultry to therapeutic rather than prophylactic or growth-enhancing purposes. Also, the emergence of new multi-drug resistant (MDR) bacteria is a reason why we must use antibiotics at the lowest levels possible.

Clinical symptoms of RDC in chickens are sneezing; open mouth breathing; head shaking; ruffled feathers; gurgling breathing sounds; discharge from nostrils and eyes; eye swelling.

Why is the poultry respiratory system more susceptible to infections as compared to mammals?
While discussing the anatomy and physiology of the chicken respiratory system, Dr. Rukadikar pointed out that, unlike mammals, the chicken respiratory system is not limited to the thorax but extends throughout the body. As a result, maintaining the integrity of the system is crucial. The invasion of the respiratory tract influences the overall performance of the birds. Nostrils, trachea, and bronchi form the upper respiratory tract (URT). The lower respiratory tract is made up of the lungs and air sacs (LRT). The URT also acts as the first line of defense in the body, preventing pathogens from entering. Air sacs are very thin-walled expansions of the bronchi that are only seen in avian species. They are found all over the bird’s body, and they create pneumatic bones when linked to long bones. Any damage or infection to the air sac can cause the bones to get infected. The cleft in the hard palate is another unusual aspect of the bird’s anatomy.

The respiratory system is also a part of the immune system.
Putting the immune system in the spotlight Dr. Rukadikar explained that the avian immune system is comprised of various branches, including gut immunity linked with gut-associated lymphoid tissue (GALT) and respiratory immunity related to bronchial associated lymphoid tissue (BALT). The BALT works by eliminating inhaled particles and keeping the airways clean, preventing or inhibiting the entry of disease-causing pathogens from the air. Several supplements can be used to promote BALT function and immunity by strengthening the respiratory tract’s immunity and defending the body against disease-causing germs.

Challenges in the monsoon season
Birds can withstand relative humidity (RH) levels of 50-70 percent. However, due to increased air humidity during the monsoon season, dampness in the shed is high. Higher humidity always adds pressure to the respiratory system and birds cannot breathe properly.

Ventilation: Poultry houses should be well ventilated. Sufficient aeration is necessary to eliminate dangerous gases such as ammonia, carbon dioxide, and carbon monoxide from the shed. Gases such as ammonia accumulation can lead to damage to the ciliated epithelium in the trachea, which is known as the first line of defense in the respiratory system. When ammonia levels reach 25 ppm, it will lead to ciliostasis, where cilia stop moving, and at levels of 40 ppm, it leads to de-ciliation, which is the loss of cilia. Weakening of the first line of defense will lead to the entry of pathogenic organisms into the LRT, causing serious diseases. Hence, it is important to keep ammonia at the lowest level with proper ventilation. Dr. Rukadikar provided evidence through autopsy images showing disease changes noticed, to emphasize the damage caused.

Filthy litter: About 80 percent of the water consumed by birds is added back to the barn through respiration and excreted as faeces. Due to high humidity, the litter may not dry quickly; care must be taken to remove caked litter.

Vaccination Reactions: Dr. Rukadikar mentioned that vaccinations have, without any doubt, contributed significantly to the health and welfare of birds in poultry farming. But live virus vaccines can sometimes lead to vaccine reactions. Certain vaccine viruses replicate in the intestinal (Newcastle disease (ND), infectious bronchitis (IB), and IBD vaccine viruses) and/or respiratory tract (ND and IB vaccine viruses). But due to replication in the respiratory tract, ND and IB vaccines provoke respiratory distress. In combination, ammonia build-up with poor ventilation in the shed leads to a weakened respiratory immune system. Hence, efforts must be made towards avoiding vaccine reactions too.

Bringing the focus on the current known respiratory diseases in chickens, Dr. Rukadikar listed infectious coryza, infectious laryngotracheitis, IB, ND, avian influenza (AI), and chronic respiratory diseases, which are primarily diseases of the respiratory system. But diseases, such as fowl cholera, aspergillosis, and fowl pox (diphtheritic form), may also affect the respiratory organs.

He then explained the strategy to be followed to overcome respiratory distress.

• Firstly, one must target improving respiratory immunity, aiming at keeping airways patent and reducing stress on the respiratory system.
• Secondly, one should try to increase hemoglobin levels in birds so that oxygen-carrying efficiency is improved.
• During the high-risk period, such as the monsoon season, one should use products that can remove excess mucus in the bronchi such as bronchodilators and expectorants.

General principles to be followed to prevent RDC:

• Cleaning and disinfection of the poultry shed between flocks to reduce bioburden.
• Avoid immunosuppression in birds.
• Continuous disinfection by spraying.
• Keeping the shed aerated, dust-free and the birds stress-free.
• As prevention of RDC, one can use herbal products that act as expectorants and bronchodilators; expand the capacity of the lungs to ease respiratory distress.

Dr. Chandan Chatterjee, Group Product Manager at Natural Remedies Pvt. Ltd., took over the session and talked about a natural way to boost the natural immunity of the respiratory system. He put forth the concept of positively modulating immunity by enhancing immunity and negative modulation by reducing inflammation.

He introduced the product Respease™ which is an herbal liquid consisting of Glycyrrhizin, Vasicine, Rosmarinic acid, and the essential oil Carvone. Respease™ improves respiratory immunity and boosts oxygenation of the cells through its hematinic activity and respiratory soothing effect.

He showed histopathological slides with evidence of increased BALT area in chicken lungs after supplementation with Respease™. The anti-inflammatory property of Respease™ was tested for its effect on COX2 and PGE2 inhibition. Both COX2 and PGE2 are inflammatory mediators. Respease™ also exhibits properties of a mucolytic, expectorant, bronchodilator, anti-oxidant, and anti-spasmodic. Supplementation with Respease™ in a field trial consisting of 30,000 broiler birds showed improved FCR, increased body weight gain, lower mortality, and improved bird activity as compared to the untreated control group. Respease™ has been extensively assessed and has scientific backing for its ability to improve respiratory immunity and attenuate respiratory distress.

The questions addressed during the session are below:

How do we take care of respiratory challenges in layers? Is week-a-month antibiotic therapy sufficient?

Dr. Rukadikar: With the growing concern about the residual antibiotics in chicken meat, it is not advisable to follow the week-a-month schedule of antibiotics for prophylactic purposes. Management tools such as clean environment, stress-free, dust-free, good ventilation, and clean sheds. Also, when going for the live IB and ND vaccines, farmers should supplement the birds with products that minimize stress on the respiratory tract to avoid vaccine reactions.

Any change in the vaccination schedule required to control respiratory infections?

Dr. Rukadikar: There is documentation that administering a live LaSota vaccine in the presence of avian influenza (AI) can lead to respiratory reactions. Hence, it is better to go for clone vaccines which do not show vaccine reactions.

Can Respease™ be used in treatment also?

Dr. Chandan: Respease™ has been designed to be used for prophylactic purposes, but it can also be used for treatment purposes.

What kind of management improvisations helps in reducing respiratory challenges in humid conditions?

Dr. Rukadikar: Avoid overcrowding.
If humidity is high and no natural air movement is present in the shed, then fix high-speed fans to help air circulation.

Does Respease™ react with any other medicine or supplements when added to water?

Dr. Chandan: Respease™ is a very inert herbal product and it is a natural product. Hence, it doesn’t react with other medicines or supplements. It is very safe to add to water.

Even though a bird’s respiratory system is advanced in comparison to that of humans and very effective, it is more prone to respiratory infection. Why?

Dr. Rukadikar: The avian respiratory system is advanced, but also delicate. The bird’s respiratory system is not restricted to one part of the body. It is spread throughout the body and any minor insult to any part of the system will spread all over.

CRD is a common problem in the field. How can we manage the situation?

Dr. Rukadikar: a. CRD is vertically transmitted from parents to offspring, hence purchasing the chicks from a known vendor where the parents are not infected.

b. Preventive Treatment: Tylosin and Tilmicosin can be used according to the prescribed dosage.

c. If there is a doubt about mycoplasma infection, then the flock must be vaccinated for IB and ND at a young age. In spray vaccination, the size of the vaccine must be very critically managed.

What is the main point of cleaning with disinfection to protect against respiratory problems?

Dr. Rukadikar: Cleaning must be done well before introducing a new flock. This is not just for the prevention of respiratory diseases, but also for other diseases. Cleaning should be done well with no residues of organic matter. This should reduce the bioburden to a great extent. And disinfection with the recommended concentration has a good effect.

Source: Dr Raina Raj, Head of Marketing, Natural Remedies Pvt. Ltd.