There are four main types of disease affecting poultry: metabolic and nutritional diseases; infectious diseases; parasitic diseases; and behavioural diseases.
Metabolic and nutritional diseases
These are conditions caused by a disturbance of normal metabolic functions either through a genetic defect, inadequate or inappropriate nutrition or impaired nutrient utilisation. These include Fatty Liver Syndrome, Perosis (or slipped tendon), Rickets and Cage Layer Fatigue.
An infectious disease is any disease caused by invasion of a host by a pathogen which subsequently grows and multiplies in the body. Infectious diseases are often contagious, which means they can be spread directly or indirectly from one living thing to another. These include Avian Encephalomyelitis, Avian Influenza, Avian Tuberculosis, Chicken Anaemia Virus Infection (or CAV), Chlamydiosis, Egg Drop Syndrome (or EDS), Fowl Cholera (or Pasteurellosis), Fowl Pox, Infectious Bronchitis, Infectious Bursal Disease (or Gumboro), Infectious Coryza, Infectious Laryngotracheitis, Lymphoid Leukosis, Marek’s Disease, Mycoplasmosis, Necrotic Enteritis, Newcastle Disease and Salmonellosis.
Parasitic diseases are infections or infestations with parasitic organisms. They are often contracted through contact with an intermediate vector, but may occur as the result of direct exposure. A parasite is an organism that lives in or on, and takes its nourishment from, another organism. A parasite cannot live independently. These include Coccidiosis, Cryptosporidiosis, Histomoniasis, Lice and Mites, Parasitic Worms (or Helminths), Toxoplasmosis and Trichomoniasis.
Abnormal behavioural patterns can lead to injury or ill health of the abnormally behaving bird and/or its companions. These include Cannibalism (or aggressive pecking).
Diseases caused by Viruses
Big Liver and Spleen Disease
Chicken Anaemia Virus Infection (or CAV)
Egg drop syndrome (or EDS)
Inclusion Body Hepatitis (or Fowl adenovirus type 8 )
Infectious Bursal Disease (or Gumboro)
Lympoid Tumour Disease (Reticuloendotheliosis)
Marek’s Disease Virus or MDV
Runting/stunting and malabsorption syndromes
Viral Arthritis (Tenosynovitis)
Diseases caused by Chlamydia
Diseases caused by Mycoplasmas
Mycoplasmosis – MG (Mycoplasma gallisepticum; MG infection; Chronic Respiratory Disease)
Mycoplasmosis – MS (Mycoplasma synoviae; infectious synovitis)
Diseases caused by Bacteria
Fowl Cholera (or pasteurellosis)
Spirochaetosis (Avian Intestinal Spirochaetosis)
Tuberculosis (Avian Tuberculosis)
Diseases caused by Fungi
Moniliasis (Candidiasis; crop mycosis)
Diseases caused by Protozoa
Diseases caused by Internal Parasites
Diseases caused by External Parasites
Several types of louse (insect; plural – lice)
Stickfast flea (insect)
Several types of mite (acarid)
Diseases caused by Metabolic Disorders
Cage Layer Fatigue and Rickets
Fatty Liver Haemorrhagic Syndrome
Diseases caused by environmental factors
Cannibalism (or aggressive pecking)
The principles of poultry husbandry
There are a number of requirements by which animals should be managed so that the best performance is achieved in a way acceptable to those responsible for the care of the animals and to the community generally. These requirements are the keys to good management and may be used to test the management of a poultry enterprise in relation to the standard of its management. These requirements are also called Principles.
The importance of each Principle changes with the situation and thus the emphasis placed on each may alter from place to place and from time to time. This means that, while the Principles do not change, the degree of emphasis and method of application may change. Every facet of the poultry operation should be tested against the relevant principle(s). The Principles of Poultry Husbandry are:
The quality and class of stock
If the enterprise is to be successful it is necessary to use stock known to be of good quality and of the appropriate genotype for the commodity to be produced in the management situation to be used. The obvious first decision is to choose meat type for meat production and an egg type for egg production. However, having made that decision, it is then necessary to analyse the management situation and market to select a genotype that suits the management situation and/or produces a commodity suitable for that market. A good example is that of brown eggshells. If the market requires eggs to have brown shells, the genotype selected must be a brown shell layer. Another example would be to choose a genotype best suited for use in a tropical environment. The manager must know in detail the requirements of the situation and then select a genotype best suited to that situation.
The following are of major importance when considering the health, welfare and husbandry requirements for a flock:
Confine the birds
- Confining the birds provides a number of advantages:
- Provides a degree of protection from predators
- Reduces the labour costs in the management of the birds
- Increases the number of birds that can be maintained by the same labour force
- Reduces the costs of production
- Better organisation of the stocking program
- Better organisation management to suit the type and age of the birds housed
- Importantly, the confinement of the birds at higher stocking densities has a number of disadvantages also including:
- Increases the risk of infectious disease passing from one bird to another
- Increases the probability that undesirable behavioural changes may occur
- Increases the probability of a significant drop in performance
- Birds housed at very high densities can often attract adverse comments
Protection from a harsh environment
A harsh environment is defined as the one that is outside of the comfort range of the birds. In this context high and low temperature, high humidity in some circumstances, excessively strong wind, inadequate ventilation and/or air movement and high levels of harmful air pollutants such as ammonia are examples of a harsh environment. Much effort is made in designing and building poultry houses that will permit the regulation of the environment to a significant degree.
It is the responsibility of those in charge, and responsible for, the day-to-day management of the birds that the environment control systems are operated as efficiently as possible. To this end, those responsible require a good knowledge of the different factors that constitute the environment and how they interact with each other to produce the actual conditions in the house and, more importantly, what can be done to improve the house environment.
A successful poultry house has to satisfy the welfare needs of the birds which vary with the class, age and housing system. Failure to satisfy these needs will, in many cases, result in lower performance from the birds. These needs include:
- The provision of adequate floor space with enough headroom
- The provision of good quality food with adequate feeding space
- The provision of good quality water with adequate drinking space
- The opportunity to associate with flock mates
- The elimination of anything that may cause injury
- The elimination of all sources of unnecessary harassment
The maintenance of good health
The presence of disease in the poultry flock is reflected by inferior performance. It is essential that the flock is in good health to achieve their performance potential. There are three elements of good health management of a poultry flock. These are:
The prevention of disease
The early recognition of disease
The early treatment of disease
Prevention of disease
Preventing the birds from disease is a much more economical way of health management than waiting for the flock to become diseased before taking appropriate action. There are a number of factors that are significant in disease prevention. These are:
1. Application of astringent farm quarantine program:
- The isolation of the farm/sheds from all other poultry.
- The control of vehicles and visitors.
- The introduction of day-old chicks only onto the farm.
- The prevention of access to the sheds by all wild birds and all other animals including vermin.
- The provision of shower facilities and clean clothing for staff and visitors.
- The control of the movement of staff and equipment around the farm.
2. The use of good hygiene practices:
- The provision of wash facilities for staff, essential visitors and vehicles prior to entry.
- The use of disinfectant foot baths at the entry to each shed.
- The thorough cleaning and disinfection of all sheds between flocks.
- Maintaining the flock in a good state of well being by good stockmanship, nutrition and housing.
The use of a suitable vaccination program.
The use of a preventive medication program.
The use of monitoring procedures to keep a check on the disease organism status of the farm, to check on the effectiveness of cleaning and sanitation procedures and to test the immunity levels to certain diseases in the stock to check the effectiveness of the vaccination program.
The early recognition of disease
Early recognition of disease is one of the first skills that should be learned by the poultry flock manager. Frequent inspection of the flock to monitor for signs of sickness are required. It is expected that inspection of all the birds is the first task performed each day, to monitor for signs of ill health, injury and harassment. At the same time feeders, drinkers and other equipment can be checked for serviceability. If a problem has developed since the last inspection, appropriate action can be taken in a timely manner.
The early treatment of disease
If a disease should infect a flock, early treatment may mean the difference between a mild outbreak and a more serious one. It is important that the correct treatment be used as soon as possible. This can only be achieved when the correct diagnosis has been made at an early stage. While there are times when appropriate treatment can be recommended as a result of a field diagnosis i.e. a farm autopsy, it is best if all such diagnoses be supported by a laboratory examination to confirm the field diagnosis as well as to ensure that other conditions are not also involved. When treating stock, it is important that the treatment be administered correctly and at the recommended concentration or dose rate. Always read the instructions carefully and follow them. Most treatments should be administered under the guidance of the regular flock veterinarian.
Nutrition for economic performance
Diets may be formulated for each class of stock under various conditions of management, environment and production level. The diet specification to be used to obtain economic performance in any given situation will depend on the factors such as:
The cost of the mixed diet
The commodity prices i.e. the income
The availability, price and quality of the different ingredients
- Maximising production is not necessarily the most profitable strategy to use as the additional cost required to provide the diet that will give maximum production may be greater than the value of the increase in production gained. A lower quality diet, while resulting in lower production may bring in greatest profit in the long term because of the significantly lower feed costs. Also the food given to a flock must be appropriate for that class of stock – good quality feed for one class of bird will quite likely be unsuitable for another.
- The following are key aspects in relation to the provision of a quality diet:
- The ingredients from which the diet is made must be of good quality.
- The weighing or measuring of all the ingredients must be accurate.
All of the specified ingredients must be included. If one e.g. a grain is unavailable, the diet should be re-formulated. One ingredient is not usually a substitute for another without re-formulation.
The micro-ingredients such as the amino acids, vitamins, minerals and other similar materials should not be too old and should be stored in cool storage – many such ingredients lose their potency over time, and particularly so at high temperatures.
Do not use mouldy ingredients – these should be discarded. Mould in poultry food may contain toxins that may affect the birds.
Do not use feed that is too old or has become mouldy. Storage facilities such as silos should be cleaned frequently to prevent the accumulation of mouldy material.
The practice of good stockpersonship
The term “stockpersonship” is difficult to define because it often means different things to different people. However, “stockpersonship” may be defined as ‘the harmonious interaction between the stock and the person responsible for their daily care’. There is no doubt that some stock people are able to obtain much better performance than others, under identical conditions. The basis of good stockpersonship is having a positive attitude and knowledge of the needs and behaviour of the stock under different circumstances, of management techniques and a willingness to spend time with the stock to be able to react to any adverse situations as they develop to keep stress to a minimum. Having the right attitude is also a very important element. The stockperson who spends as much time as possible with the stock from day old onward by moving among them, handling them and talking to them, will grow a much quieter bird that reacts less to harassment, is more resistant to disease and performs better.
The maximum use of management techniques
There are a number of different management techniques available for use by stockpersons that, while not essential for the welfare of the stock, do result in better performance. Examples of these are the regulation of day length, the management of live weight for age and of flock uniformity. The good manager will utilise these techniques whenever possible to maximise production efficiency and hence profitability of the flock.
The use of records
There are two types of records that need be kept on a poultry enterprise:
Those required for financial management – for business and taxation reasons
Those required for the efficient physical management of the enterprise
For records to be of use in the management of the enterprise, they must be complete, current and accurate, be analysed and then used in the decision making process. Failure to use them means that all of the effort to gather the information will have been wasted and performance not monitored. As a result, many problems that could have been fixed before they cause irreparable harm may not be identified until too late.
There are three important elements to good marketing practice:
Produce the commodity required by the consumer – this usually means continuous market research must be carried out to relate production to demand.
Be competitive – higher price is usually associated with good quality and/or specialised product. Therefore, it is necessary to relate price to quality and market demand and to operate in a competitive manner with the opposition.
Reliability – produce a commodity for the market and ensure that supply, price and quality are reliable.
The traditional methods of reducing microbial contamination in feed raw materials have been compromised within the EU recently with the ban on the incorporation of formaldehyde as a feed additive (PT4). Within the EU this is being linked to an increase in Salmonella isolations. With the potential for reduced chemical use to control microbial contamination in feed to be rolled out in other countries it is important that suitable alternative methods to control contamination are put in place.
One response by the industry to the ban on formaldehyde has been the introduction of new organic acid blends and novel compounds for feed sanitation. Organic acids are effective in reducing Salmonella challenges. However, they do not provide a clean, biosecure break in the mill and their performance is very reliant on formulation, the mixing performance in the mill and the time allowed for their action.
With higher generation stock as legislation tightens and public awareness heightens, the use of heat treatment for the decontamination of poultry feeds has become more popular and heat treatment is now generally seen as an effective means of Salmonella destruction in raw materials.
The purpose of this document is to review the heat treatment of poultry feeds in terms of the specifications required to ensure decontamination and the types of equipment that can be successfully employed.
Heat treatment – objectives
There are many recommendations for the heat treatment of poultry feeds published in the literature. For broiler feeds, it has been reported that a moderate level of heat treatment such as 80°C (176°F) for a two minute retention time is sufficient to kill Salmonella. In reality, it is likely to kill most of the Salmonella and damage any remaining Salmonella. By the time these damaged Salmonella start to repair and grow to reach an infective dose detectable by sampling, the broiler flock could be depleted, and the flock considered negative. With breeder flocks however, the Salmonella has a much longer time to grow to a detectable, infective dose level and Salmonella outbreaks can occur later in the life of flock. For these flocks, heat treatment temperatures for feed need to be higher for longer periods of time to ensure maximum Salmonella destruction.
So what are the specifications for successful heat treatment? Firstly, the incidence of Salmonella and the levels of contamination need to be considered. This will vary depending on the raw material(s). Literature review would generally tell us that the highest levels of Salmonella in crop-based raw materials (soya, rape meal and sunflower) would be in the region of 105 per gram. To eliminate Salmonella, heat treatment needs to be sufficient to reduce this level to zero.
Secondly, there must be a balance between the need to destroy pathogenic organisms such as Salmonella and the effect of heat on, for example, vitamin inclusion in the finished feed, the levels of starch gelatinisation achieved, protein denaturation and other anti-nutritional factors.
Once the feed has been decontaminated it is equally important to ensure that measures are in place to prevent the re-contamination of feed after treatment. A feed mill using heat treatment to produce biosecure decontaminated feed must have distinct “dirty” (i.e., before heat treatment) and “clean” (i.e., after heat treatment) areas. Heat treatment is seen as a breakpoint in the feed mill production process where decontamination of the feed takes place at a boundary between the “dirty” and “clean areas”. The clean area must be constructed in a way that will protect the feed from being re-contaminated by the dirty area. Biosecure boundaries and procedures must be in place. This commonly includes separate staff for each area and filtered air, usually to HEPA standard, to the clean area to prevent re-contamination after processing. A full hazard analysis critical control point plan (HACCP) is also required to set standards, provide a monitoring and risk analysis to the clean feed, and to monitor any deterioration in the mill structure or process conditions.
Ongoing work within Aviagen has established that heating at 86°C (187°F) for 6 minutes at 15 percent relative humidity is enough to destroy mesophilic bacterial populations at a level of 105 per gram. Knowing this it is possible to theoretically establish thermal processes (heat treatment) for different types of equipment. Different equipment will require different thermal processes to achieve the same level of reduction; because of this it is important that new heat treatment equipment is validated for efficacy to destroy Salmonella.
Heat treatment effectiveness will also be affected by the moisture content of the raw materials, the quality of the steam (moisture content) being used during the process and how the feed passes through the equipment. The feed should pass through the heat treatment equipment on a first-in, first-out basis to ensure even heat treatment.
It should be noted that the heat applied to feed as part of the process of producing pelleted feed will not be enough to kill Salmonella and should not be considered as part of the heat treatment process.
Heat treatment technology
There are a range of different technologies available to achieve the desired standards of heat treatment described earlier (86°C/187°F for 6 minutes at 15 percent relative humidity); these are listed in Table 1.
In order to produce high-quality birds, backyard keepers should start their breeding plans and select candidates. This allows producers to evaluate the individuals in their flock and identify the strongest birds.
This will help backyard keepers produce high-performance poultry and will let you know what traits to look out for and enhance with your pairings.
SOME RULES OF THUMB
The general rule for breeding is to select two candidate birds that have the traits you’re looking for. If you have two strong birds, their pairing will produce strong or above-average chicks. From there, monitor the chicks during grow out to make sure they don’t exhibit any defects. Once they reach breeding age, pairing those chicks with other strong birds will enhance the traits you’re looking for. Over time, the birds in your flock will start to become more uniform and look alike.
One of the most important aspects of successful poultry breeding is having a culling technique. According to NiceHatch incubators, it’s more about what you remove from your breeding stock than what you seek out. Breeders should be removing bad genes from their flocks and intensifying good traits in their birds. NiceHatch incubators tells listeners to familiarise themselves with the standards for the breed and make corrections if they identify traits that aren’t useful. If backyard breeders are trying to produce high-performance poultry, they need to be selective about the individuals in their breeding plan.
Once a year, keepers should evaluate the birds to see which ones are best suited for breeding. Keeping backyard birds can be expensive and time consuming – NiceHatch incubators tells listeners not to invest in sub-standard birds.
Things to avoid
“Never breed two birds with the same fault,” NiceHatch incubators says. This will only make the trait more pronounced in the chicks and lead to poorer results overall. NiceHatch incubators also warns listeners that breeding two birds with extreme but opposing qualities will not produce “normal offspring”. For example, breeding an overweight bird with an underweight hen will not produce normal-weight chicks. It will produce multiple underweight and overweight chickens.
In NiceHatch incubators’ view, breeders should put an emphasis on the birds’ vigour. He urges listeners to use chickens who, “hustle around” as breeding candidates – don’t breed mediocre birds.
Both NiceHatch incubators and Schneider agree that if one of your birds has been sick in the previous year, it shouldn’t be a breeding candidate. In a similar vein, Schneider tells poultry keepers to avoid over-medicating their birds if they want to breed them.
In his experience, backyard keepers and poultry fanciers tend to give their birds antibiotics or other treatments if they exhibit any symptoms. He urges listeners to make sure that the birds are actually sick before medicating them. Symptoms like coughing, sneezing or dropped feathers can often be attributed to dust in the air, or the birds’ natural moulting process.
If owners are concerned about their birds’ health, Schneider recommends seeking the advice of a vet before administering medications.
Remember the 10 per cent rule
In NiceHatch incubators’ experience, for every 10 birds produced, only 1 is worth keeping. For every 100 birds, 10 will be good breeding stock. For every 1,000 birds, NiceHatch incubators say that 100 will be decent, and 1 will be an “absolute knock-out bird”.
If backyard keepers have been breeding poultry for a year or so but have lacklustre results, NiceHatch incubators urge listeners to keep this rule in mind. Building an outstanding backyard flock takes time and rarely happens with a “one and done” approach. It’s a circular operation – not a linear one.
However, he did emphasise that success in breeding doesn’t rely on a huge budget. It’s better than backyard keepers learn to apply their breeding skills and knowledge to their operations. “Anybody can buy a good bird, not everybody can breed, produce or grow out a good bird,” NiceHatch incubators says. “It’s part science, it’s part art and you have to love it.”
Choosing the right incubator can be a challenge. In this article, our experts at Nice hatch incubators simplify and take you through the key factors you should consider when choosing an ideal incubator that will work for you. It is important to note that just like in any other preference; each farmer’s ideal incubator needs may differ. Remember you can always contact us at any time for clarification or consultancy regarding your challenges in poultry needs.
Egg incubator factors to consider
- Airflow in the incubator
Embryo development in the eggs requires oxygen. The chicks hatching are living organisms that not only consume a fair amount of oxygen rapidly but also produce sizeable carbon dioxide. A good airflow inside the incubator will, therefore, ensure this need is constantly regulated for the best egg hatching conditions needed. A good incubator should have air vents that will keep fresh air circulated. Some incubators may contain inbuilt fans to accelerate airflow.
- Temperature Control of the incubator
Temperature regulation is an important condition in the egg hatching process. The right temperature must be maintained at all times during this hatching process. Temperature regulation is critical since there may be weather changes as well as the differences that may arise between day and night. The inside temperature of an incubator must be keenly observed, maintained and regulated to avoid fluctuation. Fluctuations in temperatures will bring about poor egg hatching rates and loses to the farmer. The common temperature control mechanisms in incubators include wafer thermostats and digital electronic control systems. Wafer-controlled incubators allow for more fluctuation in temperature and can contribute to irregular hatches than electronically- controlled incubators. Once the temperature in a wafer-controlled incubator is set up care must be observed to avoid accidental readjustment of the tuning knob or the adjusting screw. Temperatures for some electronically controlled incubators may have been preset for hatching chicken eggs by the manufacturer, you need to know what temperature is required for each type of poultry egg species and adjust accordingly.
It is recommended that you should run the incubator for 24-48 hours before placing the eggs into the incubator to ensure that the optimum temperature needed is ready. Whenever in doubt consult your manufacture or Nice Hatch Incubators technicians.
- Humidity Control in the incubator
Egg hatching demands the correct amount of humidity all through the incubation period. It is a requirement therefore that an incubator should have moisture devices that will enable this condition to be regulated to facilitate the development of egg embryos. These devices may be in the form of inbuilt troughs, external containers, removable trays, pans, or plastic liners either with automatic self-regulation system of the manual wet-bulb thermometer (hygrometer) that measure humidity levels. Read the incubator manufacturer’s instructions.
- Ability to Observe in the incubator
Some good models of incubators have transparent covers or observation windows that allow you to observe what is happening inside the incubator. This enables the farmer to keep track of the hatching development process without having t open and disrupt the optimum conditions inside. The easier it is to observe inside the better.
- Cleaning Ease of the incubator
Once the egg has hatched you will need to move them to a brooder and cleanup the incubator for the next hatching process. The easier to clean the better.
Every venture has some costs to be incurred, your budget may determine your preferred choice for an incubator.
Keeping Turkeys is one of the greatest poultry farming choice whether you are interested in small or large flocks. One key advantage with turkeys is that they can tolerate crowded conditions and still give you a maximum return on financial investment. Turkeys are increasingly becoming a dominant domestic bird in East Africa region by peasant farmers with commercial ambitions. Commercial turkeys are reared for breast meat for the growing hotel industry and the middle class affluent population. Turkeys provide inexpensive meat for a growing urban market eager to purchase it. Although they can be successfully raised in turkey “porches” and yards, they do best when they can have range or pasture on which to forage. Poults can be raised in a poultry house on on deep litter just like chicken. The key thing is to avoid contamination from droppings is essential. Wire mesh can effectively keep poults away from soiled litter in the case of an enclosed environment.
How to get turkeys for start up
If you are a starter in poultry farming www.nicehatchincubators.com recommends that you start in the least expensive way by buying day-old poults (chicks) from hatcheries or suppliers nearby. Alternatively, you can buy turkey hens and a gobbler (cock). Turkey eggs can be hatched naturally by turkey hens, by broody chickens, or in incubators. Turkey poults are fragile and need protection for the first two months. A mother will keep them warm and protect them, provided she herself has adequate feed, water, and shelter. The incubation period for eggs is 28 days. One turkey hen can brood up to 15 eggs. The more commercial and effective way is to brood artificially through the use of incubators.
Raising, feeding, watering turkeys
Turkey poults grow fast, therefore they need high-protein feed to keep up with this growth rate. Feed your poults on starter mash as they grow, their needs taper off after eight weeks to grower crumble or pellets with lesser percentage of protein. If turkeys are on pasture and not crowded, they will get some protein from the insects and worms as they forage through your farmland.
Hanging feeders and waterers, adjusted to the height of the birds’ eyes as they grow, will reduce
the amount of feed and water wasted as the birds dig around in it with their beaks. Sloppy waterers leave wet litter to ferment and foster disease-causing organisms. Feeders on the ground should not be filled more than half-full, to keep feed contained. Turkeys are perching birds that naturally roost in trees. Poults as young as two weeks old will look for a roost. They can be accommodated with2-inch-diameter poles or branches several inches above the ground. Make an allowance of per bird depending on the population you have intend to have on your farm. Mature turkeys need stronger roosts to handle their weight and size that will support them. For mature turkeys you can use up to 2-inch diameter poles and make an allowance at least 2 feet between each pole to allow ample room for them.
Turkeys do not require routine vaccinations; However, vaccines are available for several common diseases, including fowl cholera, turkey pox, and Newcastle disease. Check with local veterinarians to determine whether such protection is necessary in your area.
BEST EGG INCUBATOR COMPANY IN NAIROBI, KENYA
When incubating any bird egg it is important to control the same factors of temperature, humidity, ventilation, and egg turning.
Temperature is the most critical environmental concern during incubation because the developing embryo can only withstand small fluctuations during the period. Embryo starts developing when the temperature exceeds the Physiological Zero. Physiological zero is the temperature below which embryonic growth is arrested and above which it is reinitiated. The physiological zero for chicken eggs is about 75oF (24oC).
The optimum temperature for chicken egg in the setter (for first 18 days) ranges from 99.50 to 99.75 o Fand in the hatcher (last 3 days) is 98.50 F.
Incubation humidity determines the rate of moisture loss from eggs during incubation. In general, the humidity is recorded as relative humidity by comparing the temperatures recorded by wet-bulb and dry-bulb thermometers. Recommended incubation relative humidity for the first 18 days ranging between 55 and 60% (in setter) and for the last 3 days ranging between 65 and 75%. Frequently there is confusion as to how the measurement of humidity is expressed. Most persons in the incubator industry refer to the level of humidity in terms of degrees F., (wet-bulb) rather than percent relative humidity. The two terms are inter convertible and actual humidity depends upon the temperature (F.) as measured with a dry-bulb thermometer. Conversion between the two humidity measurements can be made using a psychometric table.Rarely is the humidity too high in properly ventilated still-air incubators. The water pan area should be equivalent to one-half the floor surface area or more. Increased ventilation during the last few days of incubation and hatching may necessitate the addition of another pan of water or a wet sponge. Humidity is maintained by increasing the exposed water surface area.
Ventilation is very important during the incubation process. While the embryo is developing, oxygen enters the egg through the shell and carbon dioxide escapes in the same manner. As the chicks hatch, they require an increased supply of fresh oxygen. As embryos grow, the air vent openings are gradually opened to satisfy increased embryonic oxygen demand. Care must be taken to maintain humidity during the hatching period. Unobstructed ventilation holes, both above and below the eggs, are essential for proper air exchange.
4. Turning of eggs
Eggs must be turned at least 4-6 times daily during the incubation period. Do not turn eggs during the last 3 days before hatching. The embryos are moving into hatching position and need no turning. Keep the incubator closed during hatching to maintain proper temperature and humidity. The air vents should be almost fully open during the latter stages of hatching.In a still-air incubator, where the eggs are turned by hand, it may be helpful to place an “X” on one side of each egg and an “O” on the other side, using a pencil. This serves as an aide to determine whether all eggs are turned. When turning, be sure your hands are free of all greasy or dusty substances. Eggs soiled with oils suffer from reduced hatch ability. Take extra precautions when turning eggs during the first week of incubation. The developing embryos have delicate blood vessels that rupture easily when severely jarred or shaken, thus killing the embryo.
5. Position of eggs
The eggs are initially set in the incubator with the large end up or horizontally with the large end slightly elevated. This enables the embryo to remain oriented in a proper position for hatching. Never set eggs with the small end upward.
In most African countries, poultry farmers practice this for
- Home consumption
- Cultural reasons
- Income generation
Poultry farming is an income generating project which provides quality food, energy, fertilizers and is also a source of renewable asset. Income from poultry farming is used for food, school fees, buying clothing, constructing house and unexpected expenses like sickness, buying medicine.
Small scales famers in Africa are faced with some difficulties to such as poor access markets, goods and services. Some lack knowledge and skills on handling the birds, weak institutions and inappropriate technology. They also have poor poultry breeds and feeds. Poor structures for the birds. These factors affect the productivity of poultry farming and quality of the breeds produced.