How to eliminate Gumboro: a field trial.
In the last 2 or 3 decades, the avian sector around the world has grown dramatically and keeps growing to satisfy the existing high demand on this kind of meat. However we cannot keep growing if we do not keep a good health condition. Anyone involved in a breeding farm knows that a healthy animal is more productive than a sick animal. The only way to keep the animals healthy is by developing a proper immune system in a short-term period in order to produce the appropriate antibodies to protect birds against their environment. In my opinion the most important part of the bird’s microorganism is its immune system. Birds with a poor development of their immune system do not have proper protection and do not grow. That supposes silent economic losses by subclinical Gumboro around the world which represents billions of dollars.
The key to avoid the incidence of symptoms of immunodeficiency are very easy. “Trash brings trash”. Decades ago, broilers had genetic very rustic so they were very resistant. Nowadays, broilers are very sensitive; they are affected by any alteration around them. Modern birds are very good at laying eggs and breeding chicks, and by developing themselves faster which affects negatively their sensitivity. The problem of a poor immune system especially the subclinical one, causes loos of weight, production, conversion and increase the mortality. We need to keep the environment as clean as possible. It is obvious that cleanliness, order and discipline will imply an increase on their yield. When birds are comfortably located, have easy access to clean water, balanced food, receive a good handling and it exists a proper health program in advance of vaccination and medication, birds have nothing else to do than growing efficiently and consequently at low cost. The poultry farmer must understand that very expensive and automatic facilities do not guarantee the success. The most important to be successful is knowing how to disinfect the sheds and handle the equipment and the facilities. We should breed the birds in 5 –star hotels, where the priority is the comfort of them.
We always have to think of birds’ welfare, even before they are born, as well as the development of their embryos.
Here I list the 10 most important factors in order to have Gumboro under control:
-Evaluate well the vaccination program of breeding birds
-Handling of fertile eggs
-How to incubate eggs
-Preparation of farms
-Handling of chicks and their reception in farm
-Vaccination of birds
-Knowing where we are, serologies, hispathologies, growth data, mortality standards.
-Feed free of mycotoxins
-Sale, all in – all out
-Biosecurity is not an extra expense
1. Evaluate well the vaccination program of breeding birds: It is very important that newly –born chicks have enough maternal antibodies before they arrive at the farm so that they can resist the field challenges while they evolve their own antibodies. This program must evaluate constantly to ensure a proper adjustment and when choosing proper vaccines and serotypes. The use of a dead bacterine is very common within 18-20 week to increase maternal antibodies. In case of serious challenges while they are correcting the challenge, a dead bacterial vaccine can also be used at 40-45 weeks for breeding hens in order to boost the antibodies transferred to chicks newly arrived.
2. Handling of fertile eggs: When a fertile egg is laid by a hen, in many cases we forget that there is a live organism inside. It is very important to prevent intestinal problems (diarrhea) by avoiding dirtiness of nests, maintaining clean the floor and forbidding the entrance of billions of bacteria. The newly laid fertile egg is very hot and wet and acts as a sponge by absorbing everything there are outside. With this massive entrance of bacteria we are weakening the embryo (blastoderm) from the first seconds of its life, facing some contamination that can harm the proper development of the immune system of birds in incubation. In breeding bird farms, we must review periodically how we are handling the fertile eggs, collection, placement of nests, disinfection and storage. In all these processes, our aim is having everything clean by emphasising the message that says: “cleanliness will bring cleanliness and health”.
3. How to incubate eggs: hens are well vaccinated and we have excellent handling of fertile eggs. However, this one is the beginning of our challenge against Gumboro. If there is not a good incubation in advance, machines can be the source of contamination with the explosion of the famous “bomb eggs”. Eggs which have not been well selected (dirty, torn, picked them up from the floor and washed, not disinfected, handled with dirty hands) can be possible sources of contamination and bombs. These kinds of eggs should never be incubated. When these eggs are exploited they contaminate the rest of eggs around them quickly. This practice compromises again the embryo to a non desirable bacterial charge when its immune system is still very primitive.
4. Preparation of farms: the farm is the place where we have the proof of all our efforts so that the chicks are healthy in order they can express their genetic potential. Before chicks arrive, sheds must accomplish with all requirements of good practice of manufacture established in our plan of biosecurity. When a farm detects a serious challenge of Gumboro, they do not have many options but isolating the infected facilities and disinfect the farm massively. Facilities must keep under quarantine until they are declared out of Gumboro. The cleaning program must be filled in under supervision of managers, supervisors and veterinaries, ensuring that they accomplish with the additional measures of disinfection and cleanliness. In some situations we have seen that 1 or 2 feet of ground from the floor has had to be removed as Gumboro virus can stay there over 6 months. With the new regulations Farm to Fork, implementation of Good Practices of Manufacture (BMM) and use of HACCP, several leader companies have the pre-operations in farms to ensure birds have optimal conditions of handling, biosecurity and health at any time. Before chicks arrive, the farm must be declared free of contamination by the laboratorial technicians, by indicating that they have carried out a good cleanliness and disinfection before arrival of chicks. After total cleanliness of the farm, it has to wait within 2-3 weeks to introduce new animals in it. If facilities have had Gumboro the time of rest will be up to 5-6 weeks and a disinfection of all equipment will be necessary. They also have to be under control the rats and insects as they usually carry Gumboro which is propagated very quickly. We must to take into account that all viruses and insects develop resistance to common disinfectants so a rotation of materials of disinfection is necessary, as well as the use of the use of recognised brands which offer technical support. In order to increase the effectiveness of the disinfectants we must know the right doses, proper pressure of application and use of quality water.
5. Handling of chicks and their reception in farms: Chicks, especially broilers, are extremely weak and they have to gain 10 grs in the first 24 hours. A 40 gr broiler’s chick can easily multiply by 4 or 5 its weight in the first 168 hours. That means they have to gain at least one gram x hour during the first 7 days. With such a fast growth of the chick, the bursa of Fabricius also has to grow proportionally to reduce the necessary antibodies against the present diseases in the field, such as Gumboro. For this reason is very important that when chicks arrive at the farm, they receive the famous 4Cs (In Spanish: Cuidado de Calidad con Cariño Constante) which could be translated into English as quality care with constant fond. When a chick receives this special attention: comfortable environment with enough O2 and very low at CO2, proper temperature, clean water and free of insects, quality feed with a proper size for its particles, can develop efficiently a proper immune system which can give to it protection during all its life.
6. Vaccination of birds: The proper vaccination of a batch is very important and depends on many factors, especially the severity of outbreak. We remind you that modern broilers live within 1000-1200 hours which is a very short life and any hour that goes by without taking corrective decisions and use of proper vaccines, we are wasting valuable days as birds are not generating proper antibodies to face the existing challenges. It is usually advisable to vaccinate as less as possible and depend on maternal antibodies as much as possible as well as on the 4Cs (mentioned above).Currently the use of 1 or 2 vaccines of Gumboro is very common in this industry. The first one is after its birth in the incubator or in the farm, and the second one at 2-3 week old. After 21 days there is no point to vaccinate them because their lives are too short to generate an efficient response. The aim is to have an environment as less contaminated as possible so that birds can manifest their genetic potential naturally and efficiently. In a dirty environment, broilers must fight against the presence of massive contamination which weakens their capacity to yield and grow efficiently.
7. Knowing where we are, serologies, hispathologies, growth data, mortality standards: Information is power and there is no discussion about that. In our integration we are convinced that the only way to understand where we are is through the proper knowledge of our operation Real Time. In the laboratorial protocols established we must clearly fix the dates, frequencies and at ages we need to take samples to carry out the corresponding tests of serologies and hispathologies not only for Gumboro, but for other common or emergent diseases such as the current avian influenza. It is very important to establish standards for all the important parameters of different ages and measure them by making comparisons in order to detect deviations.
8. Feed free of mycotoxins: Among the factors that contribute to a depression of the immune system of birds, one of the most important ones are the mycotoxins; especially the aflatoxins and the use of low-quality ingredients such as the use of fats which do not use antioxidants or feed which do not have fungal inhibitors. When there is a problem of Gumboro, fortunately we know that we will have important problems related to the yield and the situation gets worse when we receive maize with high content of aflatoxins and we must use it because we do not have any alternative.
9. Sale, all in – all out: It does not matter if we have a challenge; the basic rule of a good farm consists of receiving all birds together and sells them all together. The reception of broilers of similar age will help us to have relatively uniform batches in weight. It is very important to receive broilers from same batches of breeding hens and breeds so that we reduce the variation of antibodies. The problem of receiving broilers from different ages and origin of breeding hens is that just 1-2% of ill birds can spread the virus gradually to the entire batch so that in a few days we can have entire batches with the immunedepression problem. Another inconvenient is that when we vaccinate these broilers, not all of them react equally to the vaccine due to the existence of a high coefficient of variation of the titles. Consequently we exaggerate the problem and this one will bring more complications.
10. Biosecurity is not an extra expense: Has passed those good old times when chicken growers used to make a lot of money without really paying attention to the very basic of poultry industry, for maintaining a good health. Throughout the world there has been a tremendous growth in the poultry industry and at the same time a significant increase in the incidence of serious disease outbreaks in much integration in the five continents. Why this occurs? We see such an increase because of the very simple factor that many of the poultry growers still do not understand that if very simple biosecurity regulations are not implemented CORRECTLY at various operations, it is going to be quite difficult to grow healthy birds and would be even more difficult to stay in business for a long time. Here we will discuss why there is such a rise in disease outbreaks in many countries and consequently increasing medication and production costs making it quite difficult in stay in business.
Ease of production and consumer concerns: Poultry products like eggs and broiler meat are quite cheap to produce are very likable, healthy, and tasty and there are no religious or cultural barriers for these products. In any country that you visit it is quite difficult not to notice the presence of poultry product promotions in every corner and neighborhood. That is good news for both the producer and the consumer, but has its drawbacks. Biosecurity, hygiene, cleanliness, salmonella and other bacteria free products have become the media news headlines. The consumers are being scared for anything; supermarkets and consumers are dictating what the direction of our business is. The media craze has reached its heights in Europe after the Mad Cow Disease, Avian Influenza in Hong Kong and Dioxin fiasco contamination. Use of some common antibiotics have been banned and more restrictions to follow. The same trends are to reach American continent sooner or later. Remember that in this business bad news spreads very quick and good things do not last much, if there is no respect for the biosecurity matters. Much large integration around the world has been able to survive and increase production with good results through solid biosecurity measures, and not sacrificing the birds comfort for theirs. We must realize that the ease of production is possible only if the birds are raised in clean houses. Frequent visitors should be discouraged, otherwise the visitor no matter of what rank in the company must and change clothes, take showers, or use adequate coveralls, etc.
Biosecurity phases: In reality the implementation of biosecurity can be divided into three distinct phases, 1] the Concept, 2] Education, 3] Full implementation of the whole chain.
1. Understand the concept: In a very simple practical language explain to all the concept of why there is a need to implement a solid biosecurity plan. Your first meetings must include all the general managers from different divisions. These would include breeder farms, hatchery, broiler and layer farms, live haul, processing plant and the feedmill. The cooperation of all these departments is extremely important for the success of the program. Present seminar type meeting with real data and clear guides. For starting a good biosecurity program, there should not be any doubts in anybody’s mind. After the concept has been explained very clearly to all the managers, make larger meetings with the supervisors and discuss the concept and give more detailed information about the program. The same training then should trickle down to all other employees of the farms including all the details. Explain the concept might sound easy, but at times in companies that do not have any biosecurity plan can be very difficult to explain and be convincing, but persistence pays off. Do not stop insisting on what we know has worked successfully. All must understand that biosecurity is not an extra expense, but a wise investment and can make a difference between success and failure.
2. Educate: After the concept has been quite clear for everybody it is time to establish a continuous plan to educate all whom have been involved in producing the eggs or the meat. Nobody should be missed in the integration, thus there will not be hearing comments that they have not told or they did not know about it. One way to clear doubts and be sure your words reach everybody is to write up a manual where every step of the biosecurity plan is clearly outlined for each department in a very simple language.
3. Full implementation of the plan: If the first two phases have been understood 90% of the job is done. When the concept has been cleared and all have been educated, really nothing else does matter. Now there is a high quality team in place scary away the unwanted pathogen microorganisms. This dedicated team to keeping the birds the healthiest know very clearly that following the basic rules discussed below is the key for success:
Location: Before constructing any farm, look around and find a biosecure location for the farm, which is far from any other poultry, or other animal farms. The selected site must be far from the poultry feed and processing plant. The more isolated the farm, the less will the risks of disease outbreaks.
Purchase a big site: The advantage of building farms far from cities and other activities is the land is going to be cheaper, thus it is strongly recommended to acquire bigger land than it is necessary. By doing this the farm can be built right in the center of the lot, avoid the neighbors around and keep distance from any activity.
Do not over build: One of the major problems that most poultry growers fell into, that want to pack as many as farms in the same lot, losing control of the very simple biosecurity rules, having less age variation in close farm vicinities. It is strongly recommended avoid cramming too many farms in a lot that was designed for less farms.
Avoid unwanted visitors: It is said that in 99% of the cases people are the main culprits to transmit diseases from one farm to other. The farm managers should realize that visitors could come from an infected farm that visited prior and infect this farm specially if entered without taking biosecurity shower or completely change clothes. Avoid taking visitors that want to sell you products at the farms; do not take sales persons to the farms. In majority of cases they can be more harmful than helpful to your birds. Talk business at the office rather than in the farm, if they must visit the farm, request that have not visited any farm at least for one week prior to visiting your instaltion.
Biosecurity does not recognize bosses: Frequent visitor should be discouraged. The visitors no matter of what rank in the company must (maximum boss or the farm administrator) should shower if necessary and change clothes, or uses adequate coveralls and disinfect boots. Biosecurity does not know borders and does not distinguish whom the boss.
Make farm entrance difficult by taking these simple measures:
• Don’t enter alert signs: Place do not enter signs at the door that clearly states unauthorized visitors are not welcomed
• Lock up the door: At all times the farm entrance should be closed and only the farm manager should have the key to the farm
• Shower: Most breeder farms in many countries use showers before entering the farm. Remember that the shower must be kept clean at all times and visitors entering the farm have taken a good shower with soap and plenty of hot water. Some companies even use showers to visit layer and broiler farms. The important message here is to follow the rules that are established by your organization. I have seen places that have installed showers, but not everybody follows the rules.
• Use coverall and boots: One simple biosecurity measure that can prevent spread of diseases among farms is changing the street clothes to clean coveralls and disinfected boots. After each visit the coverall should be washed with hot water and detergent.
• Disinfect boots: Before entering the farm be sure the boot’s sole is free from organic matters washing with water, and then disinfect it with a reliable disinfectant using a hard brush and before leaving the farm do the same.
• Keep a log: If possible keep a log of all the visitors that enter the farm. This gives you a reliable source of information and better control of all the visitors that have entered the farm during a specific period.
All in All out: This is quite basic and we have heard it many times, but the question how effectively this simple biosecurity principle is enforced? Having one age bird in one farm or various farms in one complex reduces many complexities in vaccinations, respiratory, rolling reaction problems, feeding programs and live haul. This principle is even more important for layer and breeder farms.
Checklist: Have a disciplinary clean up check out laboratory report. After the farm has been broomed, dusted, washed, and disinfected, have your lab technician run some plate tests for fungus and bacteria. If farm is declared unsuitable to receive birds, it must be re-disinfected again.
Control wild birds: Be sure there is no access or opening to the wild bird and the building is bird proof. Regularly check the wire mesh screens, doors, air inlets, and outlet preventing bird entrance to the house.
Solid rodent proof: Have an established proven rodent control program that routinely is monitored and effectively implemented.
Wash and disinfect well: When a farm to be disinfected be sure that all the steps have been taken in order as established in the original plan. It is important not to skip any part of the process. For example a farm must be totally washed, before being disinfected, and not vice versa.
Use the right disinfectants: Be sure the product used to disinfect the farm has the right doses and active agent. The water quality should be optimum for not reducing its effectiveness and when diluted to be sprayed with adequate amount of pressure to penetrate the hard to reach places.
Have frequent down times: Many field data have shown that the more down time is applied to a farm, the better will be the results. It is recommended to place at least 14 to 21 days between the flocks, and even better if the farm could be completely or partially (litter change) cleaned to reduce contamination level. However, if a farm has suffered a disease outbreak it is absolutely necessary to do a complete clean up and at least one month of down time.
Eliminate mortality: birds that die while growing or in production must have a reason, at times it is normal, while in many occasions could be due to some respiratory problems, heart attack, heat related mortality, E. coli infection or even could be due to a disease outbreak. Each farm complex no matter the size must have adequate means to eliminate the daily mortality everyday in a very proper manner. There are many methods to eliminate mortality, like hauling them away everyday, have pit holes in each farm, incinerate on site, or keep them in air conditioned chambers and be taken away once a week. A new healthy and pro-environment method to eliminate mortality could be composting the carcasses and use the end product as fertilizer. Mortalities if not disposed off adequately can become the #1 hazard for the birds in the complex and as well for the neighboring poultry farmers.
To conclude we must realize all the poultry growers in the district; province, state, country, continent and the planet earth must practice that biosecurity where the poultry growers manage more than 30 billion birds. We have explained some the basics of a solid biosecurity plan, but not all the details were discussed. The list of matters falling into a spotless biosecurity plan can go on forever, but as long as the principals have been cleared to all, each one of us can determine what the best biosecurity plan is for each operation that we work in. With the flow of information, Internet and expansion of the world market, it is going to be quite hard to hide and ignore good biosecurity management practice. You should remember biosecurity is implemented as a preventive action.