The Importance of Gut Health in Consistent Breeder Performance

The Gastrointestinal (GI) Tract

A key factor in the biological performance, health, welfare and efficiency of livestock is the health of the gastrointestinal (GI) tract. Within the poultry industry there are many initiatives aiming to understand gut health and how it can be influenced to improve production and reduce disease. These initiatives have shown that there is a need for further understanding of gut physiology and the relationship between the gut microbiota and the host. Decades of research in a wide range of animal species has shown that gut health can be influenced by a wide range of intrinsic and extrinsic factors on the farm, and understanding these factors is key for improving gut health as the poultry industry actively reduces antimicrobial use.

Optimal gut tissue development is critical for correct gut function; development of the gut starts during incubation and continues once the chick hatches out of the egg. During the first week of life, the gut tissues undergo rapid development and the villi at the gut surface elongate. During the initial villi growth the villi reach approximately 50% of their final length. If villus growth is impaired during the first two weeks of life it can have long term consequences for the absorptive capacity and efficiency of the gut in the adult bird. The intestinal tract is covered by a single layer of epithelial cells held together by cell junctions; together these create a physical barrier ensuring separation of the gut contents and the internal tissues separate. This barrier prevents bacteria from the gut from entering the body proper; failure of this barrier results in a leaky gut which allows bacteria to translocate into the gut tissues and blood stream the where they can cause disease. The result can be localized issues in the gut tissues; such as in the case of necrotic enteritis where Clostridium perfringens crosses the gut barrier resulting in severe, and sometimes fatal, damage to the gut tissues. Alternatively, when the bacteria enter the bloodstream and become dispersed around the body there can be pathology found in body systems other than the gut such as the liver, the heart and the skeletal structures. Bacterial chondronecrosis with osteomyelitis (BCO) is such a condition where failure of the gut barrier allows gut bacteria to enter the blood stream and gain access to osteochondrotic microfractures in the developing cartilage. Establishment of healthy gut architecture and maintenance of the gut barrier is therefore essential to broiler breeder performance and health. In the older breeder there is a greater risk of the gut barrier failing which increases the likelihood of bacterial translocation. As such the provision of gut health products designed to promote the gut barrier can help reduce the potential of bacterial translocation.

Development and Maintenance of Optimal Intestinal Health

Optimal intestinal health is heavily reliant upon the acquisition and maintenance of a balanced intestinal microbiota, this has become one of the key topics in poultry husbandry. Bacteria reside in all known habitats, therefore it is not surprising that evolution has resulted in symbiotic relationships between an animal and its microbial residents. The intestinal microbiome of an animal is a complex community of micro-organisms dominated by bacteria. The bacteria in the intestinal tract vary in density and species in the different compartments of the gut depending on the local environment. The gut microbiota plays a vital part in the health and well-being of its host by providing a number of benefits. The intestinal microbiota aids digestion, protects against pathogens, produces nutrients and plays a role in the development and maturation of the gut tissues and immune system. As such if the gut microbiota fails to properly develop then the gut tissues and gut immune system will also not develop correctly which will have long-term health implications for the bird.

Intestinal health is a complex area due to the wide range of management and health related factors which can impact upon the function of the gut. The gut and its resident microbiota are both dynamic entities that change as the bird ages, and understanding these changes is key to maintaining intestinal integrity to ensure optimal bird performance. Optimal brooding conditions with good access to feed and clean water are essential for optimal post-hatch gut development and long term gut health of the flock. Another key factor in the development of the villi is stimulation by the intestinal microbiota; villus length has been shown to be stimulated by lactobacilli sp. which are the bacteria which dominate the small intestine. Even though the GI tract of the developing chick in ovo is not completely sterile, the majority of colonization of the gut of the chick occurs post hatch. Sources of bacteria include the farm environment, the feed, the water supply and the litter onto which the birds are placed. The application of probiotics and competitive exclusion agents to day old chicks has been shown to aid the maturation of the intestinal microbiota and enhance the development of the gut tissues.

The Balance of Intestinal Microbiota

There is a delicate balance between the host, the intestinal microbiota, the intestinal environment and dietary compounds. An imbalance in this relationship can alter the composition of the intestinal microbiota and impact upon the integrity of the gut barrier. The shift in microbial populations can have a negative effect on the host leading to poor growth and poor performance – this is seen in cases of dysbacteriosis. Dysbacteriosis is a digestive condition of poultry and has been broadly described as an overgrowth of the intestinal microbiota leading to non-specific enteritis which can result in wet litter. Its aetiology is not fully understood but it is often seen following events which can cause physical or physiological stress on the birds such as feed changes and handling or moving the birds. Stress induced enteric upset is seen in many different animal species and has been shown to be linked to the increase in growth of certain bacterial species. The hormones released during stressful events enter the gut and the activity of certain bacteria, such as E. coli, increases which can lead to enteritis and increased susceptibility to disease. Environmental conditions also play a major role in intestinal health with a key example being the impact of heat stress on the gut. During heat stress blood is diverted to the surfaces of the bird to aid cooling, this results in reduced blood flow to the gut which can result in hypoxia and a build-up of metabolic waste in the gut tissues. The result of this is a failure of the gut barrier which reduces the efficiency of the gut and increases the risk of bacterial overgrowth and disease. Bacteria have a preferred range of nutrient sources; as such the composition of the intestinal microbiota is influenced heavily by dietary formulation. During the life of a flock there are a number of feed changes where there is a shift in energy and protein densities of diets; this invokes a change in the micronutrients available for the gut microbiota. In the event of a feed change, the gut microbiota can become unbalanced as the response to the change varies across the bacterial population and the result can be overgrowth of certain bacteria leading to diarrhea. The use of direct fed microbial products or organic acids over a feed change can inhibit the overgrowth of the less favorable bacteria during these periods and maintain gut integrity to reduce the likelihood of dysbacteriosis occurring.

Key to the Maintenance of Intestinal Health

Understanding the requirements of the developing gut to promote optimal tissue and immune system development. Furthermore being aware of how the intestinal microbiota changes at key points throughout a bird’s life and how it is possible to prepare the bird for these changes can reduce the likelihood of serious intestinal imbalances.

Dr. Anand,AGM-Technology and Product Development
Advanced Bio-Agro Tech Limited (ABTL).

Animal Feed Additives and Disease Control

When Livestock animals get sick?

Is there a different dosage for animal feed additives used for therapeutic purposes as opposed to prevention? Any gut-health additive is recommended at a specific dosage, often regulated by the law or through the registration dossier of each product according to local requirements. But, in many cases, these dosages are best estimates on what the animal needs versus the cost that can be spared by the person who buys the additive. As such, most additives are used at “prevention” dosages, quite often assuming the co-presence of other such gut-health products.

In anticipation of a health problem we were to use higher “treatment” dosages of feed additives?

When animals get sick, Diarrhea is an often a noticeable observation and one of the prominent symptoms of many diseases. In several such cases, the use of majority of additives is deemed ineffective, and the veterinarians, correctly, prescribe antibiotics to combat those problems. The question is often asked, what would happen if in anticipation of a problem we were to use higher “treatment” dosages of feed additives and would this minimize the risk of a disease outbreak?

Ideas for Future Research

In reality, we do not know. It is logical to assume that some additives could work like that, but others would be completely ineffective. In fact, some would rather not be there to unburden a diseased animal from having to cope with all the different compounds we feed them every day (another logical hypothesis).Clearly, all these are good ideas for research, and perhaps it would be best to start digging deeper into additives as disease control supplements instead of just another growth-promoting agent!

Dr. Anand,

AGM-Technology and Product Development
Advanced Bio-Agro Tech Limited 

 

The Role of Insoluble Fiber in Animal Gut

We have been actively pursuing research work on dietary fibers, and have also been discussing this topic with several parties involved in producing and using commercial fibers in animal feeds which being an increasing trend. After having discussed this topics on several occasions, it transpired to us that there is a great misconception regarding fibers. It’s not a surprise, as fiber in itself is such a complex topic and there is still lot of new things to be learned about fibers each and every passing day!The term insoluble is used mostly for cellulose and lignin or lignocellulose to differentiate these fractions from soluble fibers, such as non-starch polysaccharides. As it happens, some groups consider the term insoluble as meaning inert, whereas in reality this fraction of fibers is nothing but inert. As a matter of fact there always has been talks about the behavior of fibers before they reach the large intestine where the majority of microbial fermentation happens in mono-gastric animals, such as poultry and pigs.

 In the Gut all fibers are known to interact with water molecules..

In general, all fibers interact with water found in the gut but in practical terms it is the nature of their interaction with this water molecules that characterizes them as insoluble or soluble. Soluble fibers take in water in a process that is hard to reverse, forming a gel-like mass; the end result being a highly viscous digesta. Ignoring any effects of microbial fermentation, water trapped in this viscous mass is difficult to retrieve by the animal when digesta reaches the large intestine, where the majority of gut water is reabsorbed. Whereas in contrast, insoluble fiber does not change when it interacts with water. It absorbs water, alright, but it freely gives it back.
To get a visual aspect of this discussion, one may consider paper napkins that are composed mostly of cellulose; these are the good ones. The others that hardly absorb anything are mostly lignins — you can know and experience them because they are brittle in nature. Good paper napkins will absorb a substantial amount of water, but once squeezed, they will release it back. In contrast, we can visualize the very common breakfast item, oats porridge. There, once heated for a while, oat soluble fibers mainly arabinoxylans and beta-glucans take in water and incorporate it into their structure. If heating continues, we end up with a very viscous, almost solid, mass of oats. No matter how much pressure we exercise on this mass, little if any water will be released back.

An oversimplification, perhaps, but I hope it serves the point of understanding that insoluble does not mean inert.

Dr. Anand,

AGM-Technology and Product Development
Advanced Bio-Agro Tech Limited 

The Problem of Easily Broken Eggs in Poultry Layer Farming

 

Layer farmers during their practices often encounter situations when the poultry eggs very often break too easily? Here we summarize few of the key checks which can help in troubleshooting the problem. Firstly, check your facilities and equipment’s to ensure it is not mechanical damage. We seen considerable efforts being wasted in examining ingredients and formulas when the real problem lies in few of faulty equipment pieces.Second, check out and assess overall flock health and behavior. Your veterinarian will consult you regarding what diseases can upset the calcium cycle in the birds. In general impaired gut health can significantly impede calcium absorption, a common problem.

Once you have thoroughly examined the first two check points and have satisfied yourself that the first two check points are not the contributing reasons for the problem then, and only then, start thinking about Nutrition angle. It is imperative to find a nutritionist who understands the delicate daily calcium cycle and the factors that affect it.Also, other nutritional factors can cause eggs to be laid with a thin eggshell. With respect to calcium it is also crucial to remember that limestone is not always just calcium carbonate. Limestone, an inexpensive source of calcium (in the form of calcium carbonate), can vary widely in its calcium concentration and, of course, in impurities.

Finally, we must keep in mind that egg size and eggshell strength are bound in an Inverse relationship: the larger the egg, the thinner the eggshell. This is because a hen spends only two grams of calcium per egg, no more, no less, no matter what egg size is laid each day. These two grams will have to be spread over a larger surface as egg size increases with hen age. Some markets prefer extra-large eggs, and this is where we have been receiving most questions regarding eggshell strength.

Also, the egg quality and nutrition remains one of important topics, and we have the good fortune of working with several clients in India and south-east Asia. But at the end of the day, one can say that most of the problems have to do with reduced calcium absorption or quality of the calcium sources when it comes to this problem statement.

Dr. Anand,

AGM-Technology and Product Development
Advanced Bio-Agro Tech Limited 

Modern Broiler Production & the Surrounding Illusions in Poultry Industry

There are plenty of illusions and misconceptions surrounding how food is produced, and the poultry industry is not immune to misguided consumer views on what is healthy and what is not; what’s fact and fiction.At the Third International Poultry Meat Congress, held in Turkey, a few poultry industry myths that are circulating worldwide were examined. Some of them were new to me, others not so, so we thought it would be worth looking at them here as, while hopefully not, they may be coming to a consumer group near you.

Broilers are not chickensThe first to strike was that broilers are not chickens!Congress chairman, Professor Necmettin Ceylan, in his presentation Facts and lies in poultry meat production, referenced recent pronouncements, based on a misunderstanding of a foreign publication, that today’s broiler is not a chicken, and that this has caught the public’s imagination.The modern broiler is not a chicken because it is so different to “traditional” birds, some now believe. However, as Professor Ceylan pointed out, the domestication of the chicken goes back thousands of years and has been evolving over time. Today’s meat breeds may be heavier and consume poultry feed more efficiently, but they are still essentially the same birds.And what has happened with broiler production is no different to what has happened in other branches of agriculture. Should we not drink milk from the modern dairy cow, he asked, or buy carrots from the vegetable market?

Hormones in poultry productionAnother important illusion which was touched was the use of hormones in poultry production, a common misconception in developing countries worldwide. Because today’s chickens grow so quickly then they must be given hormones.  Most of us know and are familiar with this myth, so we won’t elaborate here, but what was new to us was that some consumers believe that if a chicken can be quickly cooked then it can’t be natural.

Chickens pumped with AGPsAnother important circulating belief is that chickens are pumped full of antibiotic growth promoters (AGPs) which have been banned in poultry production in majority of countries.

 Is Chicken a healthy option?

Then there is this belief that “village chickens,” as distinct from organic which are regulated, are somehow superior to commercially raised chickens.But as Professor Ceylan pointed out, there is no regulation of village chicken production, you don’t know where they’ve been or what they’ve eaten or drunk. They could have been roaming near heavy industry and consuming and accumulating contaminants, yet these birds are promoted in butchers’ shops as being superior.Oh, and one other point we’d almost forgotten – chickens cause cancer!If you don’t know how, we’ll explain, it comes out of their guts, of course!

Mutant seed

There’s also the issue of genetically modified organisms (GMOs) in feed, which leads to premature sexual development in males. Even if this were the case, majority of GMO legislation's across major countries worldwide makes use of GMOs in feed and food almost impossible. GMOs, many think, cause cancer, and this is somehow due to their DNA filtering into our own.But, we’ve all been eating chicken for a long time, and we’ve not started turning into chickens due to DNA transfer.Unfortunately, however, industry research has found that myths associated with GMOs are not restricted to the general public and a high proportion of physicians also believe that GMOs are linked to cancer and, perhaps more worryingly for the poultry industry, almost a third of obstetricians believe that poultry meat is unhealthy.Debunking myths and misconceptions can be hard work, but becomes all the more so when those professions that have influence in nutrition decisions are not basing their decisions on scientific evidence.We hope some of these examples may have brought a smile to your face, but they are actually quite serious issues, not only from an industry point of view, but also in terms of ensuring that the public is not only well educated, but also well fed.

Dr. Anand,

AGM-Technology and Product Development
Advanced Bio-Agro Tech Limited 

 

ABTL @Poultry India 2016 Exhibition at Hitex, Hyderabad

Mr. O.P Singh the Managing Director(MD) of ABTL gave an inspiring Inauguration speech at Poultry India Expo 2016 held at Hitex, Hyderabad. Mr. Singh in his speech highlighted major concerns of the Poultry Industry with respect to the latest emerging scenarios in India.