Natural Incubation and Broody Hen Management Practices in country birds of india: Manipulation of the broody period to increase egg production of indigenous hens

Broodiness is a condition in which laying hens have a desire to set their eggs. When hens go broody they stop laying eggs and marshal their physiological and behavioural resour Broodiness is usually presented as a normal hens’ physiological state, in which they stop laying eggs and focus on their incubation. In nature, it constitutes a normal and indispensable behaviour for the reproduction and conservation of its species. Broodiness behavior is usually seen in avian species. This behavior is dominant in wild birds and indigenous poultry compared to modern egg-laying strains. Eggs laid by indigenous chickens are usually hatched by the broody hens. Due to broodiness behavior, the broody hen sits on a clutch of eggs and incubates them to get offspring. Small-scale farmers generally depend on the broody hen to procure chicks. Like an artificial egg incubator, the broody hen controls temperature, humidity, aeration, and turning by herself. The hatchability of broody hen reported seems similar to an artificial egg incubator. The broody hen might be acknowledged as a natural incubator for operational efficiency and effectiveness. Although broodiness is associated with reduced egg production, it contributes a significant role in enhancing the rural poultry population by supplying chicks. Moreover, the loss of egg production due to broodiness can be minimized through management interventions.

However, in modern days’ bird breeding broodiness is usually seen as something negative that affects production, and not as a normal and natural way to conserve the species. This is one of the reasons why artificial incubation has gradually been introduced. This phenomenon has pushed chicken breeders to reduce its appearance through genetic selection, to the point that broodiness has become less frequent in recent years.

What Makes a Hen Go Broody?

A broody hen instinctually wants to have chicks; her hormones in a season of life, breed type, and daylight hours can bring about this change.

• Hormones – The broody hen is typically at least a year old and has already had a season of laying eggs.
• Breed – Some breeds, such as Sussex, Leghorns, and our favorite, Novogen Brown chickens, tend to be less broody. Buff Orpingtons, Brahmas, Austrolorps, Slikies, or Cochins tend to be more broody. A good general rule of thumb is that the heritage breeds will be more broody as the hybrid breeds have had this behavior selectively bred out of them.
• Daylight – As spring days grow longer and warmer, ending the long cold winter when the hen’s egg production slows, spring fever can produce a broody hen with attitude. She will collect her eggs and, at times, other hens’ eggs, sitting on them day and night, trying to incubate and hatch a little family of chicks.

How Long Will a Hen Stay Broody?

• The hen will stay broody for around 21 days to complete her nesting cycle. That is how long it takes to hatch a clutch of fertilized eggs.

Signs of a Broody Hen

The signs of a “broody” hen are easily identified when you know what to look for.

• Nesting – The broody hen will sit on the nest for endless hours day and night, only leaving to eat, drink and defecate once a day. Using the deep liter method for backyard chickens is crucial for our chicken’s health; going outside multiple times a day and leaving the nest makes this method possible.
• Roosting – The broody hen will not leave the nest at night to roost with the other hens. She will stay in her undisturbed, dark area, trying to keep her eggs separate and warm.
• Egg Hoarding – The broody hen will hoard her eggs and the other hen’s eggs, nesting them with her own. This can create “hen havoc” in the coop.
• Feather Loss – Broody hens will pluck out their chest feathers so their skin directly touches the eggs to provide more body heat.
• Aggression – The broody hen will be highly protective, squawking and pecking at you as you try to remove the eggs or her from the nest. Aggression that isn’t usually a problem becomes one quickly!
• Stop Egg Production – The broody hen will stop producing eggs until she hatches the clutch, a twenty-one-day process that lowers overall egg production.

Ways to Encourage Brooding Behavior

If you have chosen a chicken breed that is more likely to go broody and you want to encourage this behavior, there are a few things you can do:

• Pseudo Eggs – Place “eggs” such as golf balls, Easter, ceramic, or wooden eggs in the nesting area to lure the hen to come to sit on them.
• Feed and Water – Make feed and fresh water easily accessible to encourage the hen to stay put.
• Seclusion – Give your hen a quiet and private area away from the rest of the flock. You can even add curtains to the nesting area to help darken the area making the hen feel more calm and secure.
• Nesting Material – Place a generous amount of nesting material to make a soft area for her fragile eggs to lay.

How to Redirect a Broody Hen

If you prefer your hen not to go broody, here are some ways to redirect your hen’s behaviors.

• Remove the Eggs – Managing your hen house daily and removing the eggs promptly can prevent a hen from becoming broody. Homesteading Hack: Always use best practices for handling farm fresh eggs safely.
• Remove Nesting Box – Take away the broody hen’s ability to nest by removing the nesting box first thing in the morning after removing the eggs. Homesteading Hack: If she doesn’t cooperate, gloves are recommended!
• Isolate – If the broodiness continues, remove the broody hen from the coop. This removes her from the nest and the ability to sit on eggs. Place the hen in a separate cage with a wire bottom for several days or longer. Make sure the hen has plenty of food and fresh water.
• Move Nesting Area – When the hen returns to the coop, move her nest to a different location to help with the reset.

• Chill the Nesting Area – Chilling down the broody hen’s nest with ice packs can effectively stop he from sitting all day and night brooding.

• Homesteading Hack: Occasionally, a hen will stay broody; perhaps her hormones have not stabilized. She will become aggressive with her chicks, and you must break her broodiness immediately. 

Identifying broodiness’ features

Physiologically, broody hens are recognized for their resistance to leave the nesting box, bristling feathers, loss of appetite, increased pecking and for emitting a hoarse sound. Broodiness consequences in the poultry industry directly affect egg fertility rates and production, since hens tend to reject males.

Broodiness in industrial coops is often caused by mismanagement:

• excessive animal density
• insufficient number of feeders and drinkers
• inadequate ventilation
• poor luminous intensity or lack of lighting uniformity
• excessive permanence of eggs in the nest boxes
• insufficient bird weight and
• excessive batch heterogeneity
• nesting boxes remain open at nigh
• excessive number of nests
• lack or excess of active roosters
• presence of a subclinical pathological process

Although genetics may play an important role as it is a normal bird physiological process.

Possible causes of broodiness

This phenomenon is caused by prolactin hormones secreted in the anterior lobe of the pituitary gland. It is highly influenced by light intensity and, to some extent, its greater or lesser presence will depend on climatology; a warm or temperate environment.

Broodiness manifests more in some chicken breeds than others, so it is hereditary. Although very little is known today about how this character is inherited. Some cross-breeding studies show the hypothesis of complementary genes by genes linked to chicken gender and others favoured by maternal inheritance.

Need of preservation of different chicken breeds

In this sense, it would be necessary that poultry farming authorities of different countries, geneticists and universities made the commitment to preserve different chicken breeds and, in doing so, avoiding the loss of genes that may be useful to keep developing new chicken lines in the future. Poultry is, after all, of extreme importance as a source of protein for human consumption.

Hence, the need to establish different breeds’ genetic profiles is key to avoid excessive dependence on just a few monopolistic breeding farms. Often, the negative effects before the outbreak a sanitary-type pandemic are left out. A ban on animal -and animal products- exportation from one country to another due to a disease outbreak may have negative consequences not only production-wise, but for price stability and the supply to the food market.

This is a favourable condition if one wants to produce chicks through the natural nesting process. It is, however, a detrimental condition if one is only interested in maximizing egg production. If one wants to achieve maximum egg production from their flocks, then one must minimise the incidence of broodiness. Broodiness can reduce egg production by as much as eight to 10 eggs per hen.

Broodiness is controlled by several factors including genetics, endocrinology and the environment. Fortunately, the environment can be a significant contributor to broody behaviour and, as a result, can also be manipulated to discourage this condition.

The following are two methods that may be used to alter the hen’s environment to discourage broody behaviour:

1. Broody pens or coops

Broody females are placed in an isolated pen or coop similar to the laying pen except there are no nest present. Removing the hens from visual and physical stimulations provided by nest and nesting material will help discourage this behaviour. In addition, it will help prevent producing hens from observing and adopting the broody behaviour of their flock mates.

The hens should be held in this isolation pen for seven to 10 days before moving them back to the laying pen.

Depending on the number of hens with broody behaviour, multiple broody pens may be necessary. Rotating hens between pens with different feed and water locations and without nest will discourage nesting behaviour. This procedure of pen rotation may have to be repeated several times to stop the broody condition.

2. Broody pens plus light

Light intensity and duration are important factors in stimulating egg production. It has been well established by poultry scientists that low levels of continuous artificial light, i.e. 0.5 foot candles for 12 hours or more, will provide enough stimulation for maximising egg production.

Thus, the use of artificial light to stimulate egg production and break broody conditions in hens has been in use for many years. Using light stimulation in conjunction with a broody pen is more effective than simple pen rotation methods.

With this procedure, the coop or pen is equipped with a light(s) hung approximately four feet above the floor. Using 60 to 100 watt bulbs will provide the needed light intensity. Light should be provided for a minimum of 12 hours per day while the hens are in the broody pens.

Using pens or coops with wire floors will also discourage broody behaviour. Wire floors will not provide the hen the sensory materials, e.g. dirt or grass, to facilitate nesting behaviour.

Broodiness is a natural behavior to incubate a clutch of eggs for the purpose of getting offspring. Broodiness is usually seen in female birds, but certain male birds and non-avian species also show this behavior . After laying a clutch of eggs, the female birds usually become broody and sit on the eggs to incubate them. The behavioral pattern of broodiness varies in several avian species. The cuckoo bird does not show this behavior, but they lay eggs in the nest of other birds . There are some species where both male and female partners contribute to incubate and take care of offspring. In pigeons, broodiness can be seen in both male and female partners . Broodiness consists of two parts: incubation process and brooding of animals . To complete the broodiness period, the broody hen passes a considerable period of time without egg-laying. As broodiness hampers egg production, the scientists have worked on it and developed layers of non-broodiness character. Due to continuous selection and breeding, the incubation behavior has changed or extinct over the time in several species, but this behavior is essential in wild birds to maintain their existence.

The modern poultry is reared for specific production purposes, either for meat or egg production. In modern poultry industry, broodiness is a nuisance as production loss is associated with this behavior . With the advancement of science and technology, egg incubator has been introduced in the poultry industry to hatch lots of eggs artificially. Along with the modern poultry industry, the rural poultry is also contributing an important role since the beginning of poultry production . In many countries, the rural poultry contributes the maximum percentage of meat and eggs for the nations . The contribution of rural poultry is more intense in developing countries. Usually, the farmers in the rural areas use broody hens to fulfil chick’s requirements without using artificial egg incubators. The broodiness character in indigenous poultry is important for rural poultry production. To hatch the eggs, broody hen provides optimum temperature and humidity to eggs and maintains turning by herself. The broody hens are working like a natural incubator in rural areas. This study will give an understanding about the broodiness and broody hen management. In this review, the importance and role of broody hen have been discussed.

2. Factors affecting broodiness

Though broodiness is a natural instinct, there are several factors that might affect intensity of broodiness in avian species.

1. a) Breed or strain: Broodiness is a heritable trait in poultry . There are hundreds of chicken breeds and varieties in the world having specific broodiness characters. These chicken breeds are generally included into Asiatic, Mediterranean, American and English classes. Breeds of each class possess specific broodiness character. Generally, Asiatic breeds show high broodiness, Mediterranean breeds show low broodiness, English and American breeds show medium broodiness character. The broodiness character also varies among the breeds categorized into egg, meat, dual and ornamental purposes on the basis of their utility . Generally, high egg-laying birds show low broodiness character, meat type birds show high broodiness and dual-purpose birds show moderate broodiness character. b) Age of the bird: Age of bird is related with the intensity of broodiness in the hen. Usually, young birds show less broodiness character. Chicken at age of 41–47 weeks may be suitable for selecting broody hens  as the medium aged (40–61 weeks) hens give high hatching percentage compared to early and old aged birds .c) Season of broodiness: The incubation season is also important as both the farmers and broody hens prefer to incubate eggs at a particular period of the year. The highest percentage of hatchability by broody hen was reported during winter season . The farmers prefer October–December for incubating eggs due to availability of feed and high chick survivability during this period . Possibly, photoperiodism plays an important role in regulating egg laying and broodiness character.
2. Broody hen performs as a natural incubator

a) Temperature: The body temperature of hen ranges from 40–41 °C. During incubation period, the temperature transfer by broody hen to eggs is about 38–39 °C . To heat transfer, the broody hen undergoes molting processes. Feathers from the underside of hen are molted, the skin becomes thickened and blood flow increases to the skin. The featherless skin becomes warm and transfers the heat to eggs, thus helping the eggs to keep warm . b) Turning: Turning of eggs are important to prevent adhesion of embryo to shell membrane. Research result shows egg turning 24 times a day at 45° angle gives high hatchability when egg is incubated in artificial incubator . Though the frequency and positioning of egg turning are unknown at natural incubation process, broody hen maintains the egg turning by her body movement. The turning is specially done when the hen moves from the nest and return to the nest by her body movement . c) Ventilation: Ventilation of eggs is important and broody hen provides fresh air around the eggs by spreading her feathers . d) Humidity: Humidity of eggs may be controlled by sweating the skin of broody hen or egg itself to maintain humidity for egg incubation . e) Cooling of eggs: Cooling of eggs is also important during egg incubation. Eggs become cooler when the broody hen leaves the nest. In natural incubation period, the hen leaves the nest for about 30 minutes during the first 15–18 days but the hen rarely leaves the nest during the last 3 days of incubation . f) Performs like a brooder: The thermoregulatory system is not developed in newly hatched chicks . Brooding is an important part of poultry rearing to develop thermoregulatory system in chicks. The broody hen works like a brooder. The hen gives warmth to the chicks by sharing temperature from her body. g) Feeding and watering of chicks: The broody hen helps to breakdown large feed particles and share the small feed particles with the chicks . During rearing period, the broody hen teaches their chicks how to eat feed and social interaction which might help them to be more positive and responsible when they will be a broody hen . h) Protects the birds from predator: Most of the birds in rural areas are reared under scavenging conditions. In rural areas, birds have to face the predators such as crows, mongooses, eagles, and foxes surrounding them  . The loss of chicken in rural area due to the predators of foxes, crows, mongooses and eagles are remarkable. The mother hen minimizes the loss of chicks during early life of chicks by covering the chicks under her feathers. The broody hen may also influence in the development of chick behavior .

4. Broodiness cycle of indigenous hen

The indigenous birds having broodiness character undergo a sequence of behavioral changes to complete the brooding cycle. The behavioral pattern within the brooding cycle is almost consistent and happens sequentially. The cycle starts from the beginning of broodiness behavior to return this behavior after incubation, brooding and rearing, and egg-laying . To incubate eggs, the broody hen sits on a clutch of eggs (12–17 eggs per clutch) after egg-laying. She incubates chicken eggs for 21 days. After hatching, the mother hen rears the chicks for up to 63–84 days or start egg-laying again. Each cycle covers on average 96–122 days, thus 3–3.5 cycles per year . However, hens with previously experienced brooding show a comparatively shorter brooding cycle . Intervention to improve management may increase the number of cycles from 3 to 6 through shortening total days per cycle from 122 to 68 days .

5. Broody behavior

Usually, the indigenous hen starts to incubate their eggs after laying a clutch of eggs. This broodiness character might lead to several changes at behavioral and physiological level of broody hen. The broody hen starts to sit persistently during the last five days before fully broody, show reluctancy to get up off from the nest even there is no eggs in the nest . If she leaves the nest once or twice a day, return quickly after feeding and drinking. The feed and water intake reduce during the broody period . She becomes aggressive and may bite if somebody try to reach near her nest or touch the eggs under her. She fights with other hens or species to protect the eggs in nest.

6. Hormonal regulation of broodiness

Broodiness is regulated by central nervous system . Several studies reveal the association of hormonal regulation with egg-laying to incubation behavior in birds. The most studied hormones during the incubation period are luteinizing, progesterone and prolactin. These hormones are considered to be related with egg-laying to incubation in birds. The concentration of these hormones varies depending upon the stage of egg production, incubation and rearing of chicks by broody hen. During egg-laying period, the concentration of luteinizing hormone and progesterone in the blood is high. Their concentration decreases during the incubation period . On the other hand, prolactin concentration decreases during peak egg production  and increases during incubation period . It emphasizes that prolactin induces broodiness , and luteinizing and progesterone induces egg production in birds. If a hen become broody, she stops egg-laying and become busy to incubate her eggs. After broodiness period, prolactin concentration decreases sharply  and increases the luteinizing and progesterone hormone to initiate egg laying . Again, when nests are allowed the reserve situation happens . Another reported hormone thyroid is probably play important role in losing incubation behavior in chicken like Leghorn breed .

7. Broody hen management

There are some birds show high broodiness, whereas others show less or non-broodiness character. The hen aged more than one year and having broody characteristics should be selected for this purpose. Keeping some eggs or dummy eggs in the nest for long time may encourage the hen to go broody. The nesting materials should be comfortable for birds. There should be plenty of feed and drinking water near the nest to discourage movement of broody hen. There is a prevalence of ectoparasites such as lice, mites, tick, and flea in backyard chicken, and control of these ectoparasites are important for smooth functioning of broody hen . After egg hatching, the hen becomes engaged to brood and rear her chicks for a long time. Generally, non-broody hen produces more eggs than broody hen, but the compensation of egg loss can be managed through improved management during broody and non-broody period of hen . It is important to rear the chicks separately for quick return of hen to start egg-laying again. Each cycle can be shortened through management interventions like chick separation and practices of creep feeding . The creep feeding play important role to gain high body weight of chicks and reduce chick mortality . As the chicks get older the broody hen gives less time to brood and rear her chicks and return quickly to start egg-laying. If broodiness is not desired, the behavior might be reduced through several interventions from being going a hen broody . Immediately after laying eggs, remove the eggs from the egg laying box. The broody hen should be kept away from the nest after egg-laying. To break the broodiness, there are some practices in the rural areas like placing uncomfortable materials in the nest that discourages the hen from going broody.

Broody hen can incubate eggs efficiently with high percentage of hatchability. She provides optimum temperature, humidity, ventilation and other essentials efficiently to hatch eggs as a natural incubator. After hatching, she broods the chicks and protects them from predators. Though broody behavior reduces egg production, the loss may be minimized through improve management interventions.

NATURAL INCUBATION

The broody hen chosen for natural incubation should be large (to cover and thus keep more eggs warm), healthy and preferably vaccinated, with a good brooding and mothering record. Signs of broodiness are that the hen stops laying, remains sitting on her eggs, ruffles her feathers, spreads her wings and makes a distinctive clucking sound. Brooding may be induced with dummy eggs or even stones.

Eggs usually become fertile about four days after the rooster has been introduced to the hens. A maximum of 14 to 16 eggs may be brooded in one nest, but hatchability often declines with more than ten eggs, depending on the size of the hen. Feed and water provided in close proximity to the hen will keep her in better condition and reduce embryo damage due to the cooling of the eggs if she has to leave the nest to scavenge for food.

The hen keeps the eggs at the correct humidity by splashing water on them from her beak. This is a further reason for providing her with easy access to water. In very dry regions, slightly damp soil can be placed under the nesting material to assist the hen in maintaining the correct humidity (between 60 and 80 percent). Fertile eggs from other birds are best added under the brooding hen between one and four days after the start of brooding. In Bangladesh, it has been reported that local broody hens will even sit on and hatch a second clutch of eggs, often losing considerable weight in the process (especially if insufficient attention is paid to the provision of food and water).

The incubation period for chicken eggs is 20 to 21 days, and increases up to 30 days for other poultry. After sitting for some days, a broody hen can be given some newly hatched chicks and, if they are accepted, the original eggs can be removed and replaced with more chicks. Thus hens with a better record of mothering can be better utilised for their abilities.

Eggs initially need a very controlled heat input to maintain the optimum temperature of 38°C, because the embryo is microscopic in size. As the embryo grows in size (especially after 18 days), it produces more heat than it requires and may even need cooling. Moisture levels of 60 to 80 percent Relative Humidity (increasing during the incubation period) are important to stop excess moisture loss from the egg contents through the porous egg shell and membranes. Factors to consider for successful natural incubation include the following:

• Feed and water should be close to the hen.
• The broody hen should be examined to ensure that she has no external parasites.
• Any eggs stored for incubation should be kept at a temperature between 12 and 14 °C, at a high humidity of between 75 to 85 percent, and stored for no longer than seven days.
• Extra fertile eggs introduced under the hen from elsewhere should be introduced at dusk.
• The eggs should be tested for fertility after one week by holding them up to a bright light (a candling box works best. If there is a dark shape inside the egg (the developing embryo), then it is fertile. A completely clear (translucent) egg is infertile.

A hatchability of 80 percent (of eggs set) from natural incubation is normal, but a range of 75 to 80 percent is considered satisfactory. Setting of hatchings is best timed so that the chicks to be hatched are two months of age at the onset of major weather changes, such as either the rainy (or dry) season or winter/summer. A plentiful natural food supply over the growing period of the chicks will ensure a better chance for their survival. Successful poultry species instinctively lay and incubate their eggs at a time of the year when newly hatched chicks will have a better supply of high protein and energy food provided by the environment. For example, guinea fowl will only lay eggs in the rainy season. However, seasonal changes in weather patterns are also times of greater disease risk.

Summary Points

• The incidence of broodiness decreases egg production. On the average, egg production is reduced by 8 to 10 eggs each time a hen becomes broody.
• Inspect nests regularly and keep records on birds that you suspect of becoming broody.
• Remove broody birds as soon as possible and place them in a broody pen.
• Provide artificial light, if possible
• Maintain the birds in the broody pens for a minimum of 7 days before returning to the laying pens.
• Repeat this process as needed.

If a broodiness control programme is conscientiously followed, egg production will be increased in your flock.

INCUBATION AND HATCHING OF POULTRY EGGS

INCUBATION AND HATCHING OF POULTRY EGGS

Compiled  & Shared by- This paper is a compilation of groupwork provided by the

Team, LITD (Livestock Institute of Training & Development)

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Principles & Practices  of Poultry Breeding in India