Avian Endocrine Systems – Hormones in Poultry

The Endocrine system consists of various glands and nodes which secrete hormones. Hormones are chemical messengers which travel in the blood to activate target cells. These target cells have special receptors, into which only certain hormones can fit. For example, testosterone act on the male gonads, but not the adrenal glands.

Hormones tell the body what to do. The endocrine system is closely linked to the nervous system, because both deal with communications and co-ordination, but there are a few distinct differences.

Hormones Act slowly, and for a long period of time. They cause gradual changes.

Nerve Impulses Act very quickly, and only last for an extremely short period of time. The changes they cause are instant.

Below are some of the main avian endocrine glands:

Pituitary: The pituitary Gland is sometimes called the master gland. It sits in the brain base, and releases various hormones which trigger other endocrine glands to release hormones. It has two parts, the anterior and posterior lobe. It releases:

  • Natural Growth Hormone
  • Thyroid Stimulating Hormone
  • Adrenocorticotrophic Hormone (ACTH) – Stimulates the adrenal cortex
  • Sex hormones (LuteinisingHormone (LH) and Follicle Stimulating Hormone (FSH)) – To stimulate the sex glands
  • Melanin Stimulating Hormone – Unknown function (in birds)

The posterior pituitary also produces arginine vasotocin and stores oxytocin both of which play a role in egg yolk release.

Hypothalamus

The hypothalamus is located centrally in the brain, at the base. It produces oxytocin as mentioned above, and plays a role in controlling the anterior pituitary gland.

Pineal Body: This is a small gland in the centre of the brain. It produces melatnin through the ue of tryptophan (a type of amino acid). Melatonin affects electrical goings-on in the brain, and behaviour, as well as sleep.The Pineal body has been described as a ‘biological clock’ and part of it function is to alert the hypothalamus as to when  to release certain hormones. An example of this is laying. In the wild, birds only lay in spring, because the pineal body ‘tells’ the hypothalamus that spring has come, and the hypothalamus begins producing LH and FSH.

Adrenal Glands: These are a pair of small glands, some 9mm long, located in front of the kidneys. They have two regions, the adrenal cortex and the adrenal medulla. The cortex produces 3 hormones…

  • 8-hydroxycorticosterone – A hormone with an unknown function
  • Corticosterone – Stress reaction, protein breakdown, fat and carbohydrate metabolism
  • Aldosterone – Regulates sodium retention

The medulla produces two compounds:

Epinephrine – This plays a role in controlling blood pressure

Norepinephrine – Fat metabolism

Thyroid Glands

These two glands are found at the base of the neck, each one lying at a different side.  They produce:

  • Triiodothyronine – Involved in feather (and beak and skin) development. Scientists think it may be involved in the moulting process
  • Thyroxine Regulates carbohydrate metabolism, heat production and promotes high blood sugar and growth

Parathyroid Glands: are two assisting bodies located behind the thyroid glands. They produce Parathormone which regulates and controls the calcium level in the blood.

Ultimobranchial bodies: These are located behind the parathyroid glands. They produce calcitonin and lower the blood calcium, thus calcitonin and Parathormone must be in balance.

Islets of Langerhans: This group of specialized cells is located in the  pancreas. It produces two hormones:

  • Glucagon – Raises blood sugar, and affects fatty acids
  • Insuli – Lowers blood sugar

Gonads:

Gonads or reproductive organs produces these hormones:

  • Testosterone
  • Progesterone
  • Oestrogen

All of the hormones are needed in both genders, but the amounts vary. Hens need a lot more of the latter two, while cockerels produce much more of the former. When a cockerel is casrated, he becomes a capon and stops producing testosterone. Overtime, he takes on the behaviour, and to some degree, the appearance of a hen!

 

 

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National Poultry Show Great Britain Will Be Held November 2012

After a very successful 2011 Show, the 2012 Show will be held on Saturday and Sunday 18th and 19th November 2012. As usual, the Show will feature around 6,000 representatives of about 135 different Large Fowl, Bantams, Turkeys, Geese and Ducks. There will also be competition classes and sale pens, as well as a Restaurant. Music and a Bar will also be available (Saturday Night Only).

On Saturday, the show is open to the public 10.00 a.m. to 4.00 p.m, while on Sunday it is open 9.00 a.m. to 2.00 p.m. The venue will be Stoneleigh Park, Stoneleigh, nr Coventry, Warwickshire, CV8 2LZ.

More details can be found here, and the schedule can be there soon.

The function and science of the avian ear



Do Chickens have ears? Yes! And in this article I will explain how they work.

Even though chickens ears are seen only as small,  fleshy red or white earlobes, or auriculars (also known as ear coverts), the inner ear channels and amplifies sound, and plays a significant role a one of the senses.

Near the auriculars and below and behind the eye, the ear is located. The auriculars channel sound waves into the ear opening,  and towards the eardrum, a thin membrane that vibrates in accordance with the sound waves. The waves are passed down the columella, one of the smallest bones in the avian body, and transmitted to another membrane called the oval window via the cochlea in the middle ear. The cochlea is filled with fluid, and tiny hairs called cilia are attached to its walls. They move with the sound vibrations, as blades of grass do in the wind. Vibrations are translated into electrical impules, and sent to the brain via the auditory nerve.

When human cilia are damaged, they never re-grow, and so throughout life, hearing slowly decreases. The same happens in birds, right? WRONG!!! Birds can regenerate their cilia!!!

Avians also have semicircular canals, the saccule and utricle, which regulate balance, just as they do in humans.

I hope this was interesting, feel free to browse my website!

 

Eni’s Rare Breed Chickens has Twin Websites!!

Enis rare breed chickens has a twin website!!!! It is called TX Stock Photos. It sells photos, graphics and videos, and has a wide range of subjects, but specializes in quality countryside and equine photos. You can visit it here. It has not yet launched, but will do so in 2013.

It also has a blog, where regular information on photography, new camera releases and tutorials in using adobe photoshop is posted. The blog is a rich yet reliable information fest for photographers of all abilities! You can visit the blog here.

Check out its facebook page and like it! Follow on twitter and Google +!

It is also twinned with Pony Galaxy,  a website that is… All about horses and ponies!!! This site will make all horse and pony lovers feel at home. In paradise in fact! This blog is full of reliably sourced information, and is really worth checking out! Also check out its facebook pagetwitter page and Google + page.

Banish Bad Behaviour!! How-to Have Harmonious Hens!!!

Banish Bad Behaviour!!

In general, chickens are social animals, living in peace and harmony. When a new bird is introduced, this harmony is temporarily disturbed as the hens squabble to sort out their pecking order. The pecking order is the heirachy by which chickens live. The hens have a little squabble, and the hen that wins is the dominant hen. She gets access to the food and water first, and can put any hen who dares confront her back in her place with a sharp peck. On the other hand, the lowest ranking hen gets to go to the food last, and can be pecked at by any hen. Because of this system, hens live in peace, but when the balance is upset, peaceful Poppy can turn into ferocious Frostie.

In this article, I will cover a few points of bad behaviour and give some tips on how to deal with it.

 

Excess noise

It is usually the cockerel who makes the most noise, while crowing, this can only be avoided by not keeping a cockerel. Cantrary to popular belief, it is not necessary to keep a cockerel to get eggs. The cockerel is only needed to fertilize eggs. Sometimes, a hen will make lots of noise, when she has layed an egg. If this is her habitual egg laying noise, it is not possible to stop her from making the noise, but a few steps can be taken to reduce the amount of noise she makes. These include:

  • Reduce boredom (see below)
  • Reduce stress
  • Practise good husbandry

 

Boredom

Overcrowding and small pens can cause boredom, which often manifests itself as feather pecking in adults and foot pecking in chicks. Chickens are attracted to red, (which is why feeder bases are often red), so if blood is drawn cannibalism can be the result. You should always keep some genitian violet spray handy because this is antibiotic, and stains the wound purple, to stop the chickens from attacking the hen.

Boredom can be prevented or alleviated by;

  • Scattering grain over the ground to encourage them to forage ‘naturally’
  • Hanging up bunches of green leaves for them to peck at
  • purchasing, and hanging up blocks of seed

 

Fighting

This often happens when two cockerels come in contact with each other. This is why cockerels should be kept apart. This takes place over hens, territory, etc.

Fighting can also be found with hens, when a new hen is introduced, for example. This is done to establish the pecking order. Once this is established and all the hens know where they stand, peace will return.

Egg eating is addressed here. Corresponding section highlighted pink.


Chickens respiratory system- science of breathing and lungs

Because of the energy required for flying,birds have a very high demand for oxygen. Even though chickens don’t fly much, they still maintain these characteristics.

han being a single ‘bag’ for air, they have air sacs spread around their organs, and in their bones which help keep the pressure of air in the lungs constant.

When a bird inhales, half the air passes through bronchi to the posterior (back) air sacs, and the other half goes to the anterior (front) sacs and the lungs. That in the posterior sacs is emptied into the lungs, rather than alveoli, gas exchange takes place between the blood capillaries and the air ‘capillaries’ known as para bronchi. Compared to mammalian gas exchange, that that takes place in birds is much more efficient because the partial pressure is the same as that of the environment.

Their lungs are quite different to mammal lungs, because, rather t

 

They have no diaphragm, and therefore air flows into the lungs and is pushed out by muscular contraction.

Located at the bottom of the trachea (windpipe) is the syrinx, the birds voice box, and as they exhale they can crow, cluck etc…

Hope you liked this post, please check ot my other posts!

 

 

Basic General Chicken Facts

Male chickens are known as roosters or cocks or cockerels, females are known as hens or pullets. Castrated males are known as capons, but castrating chickens seems a silly and expensive option to some people who reckon its easier not to have a cockerel if they dont want chicks.

Cockerels are generally distinguished by larger head furnishings (combs and whattles) and colourful plumage (feathers).

Head furnishings direct the blood to the surface to keep the chickens cool. In winter, when its cold, chickens head furnishings may seem a little more pale than usual, this is because vasoconstriction occurs, which is where the blood vessels near the skin narrow and more blood is directed deeper down to conserve heat.

A chickens Brain- The Science

Did you know that chickens have a concept of the future?

Scientist used tho think that only humans and higher primates had brains with structure that is complex enough to allow forethought. The complex arrangement of the neurons, and the  fact that they have a concept of the future suggests that they are intelligent enough to worry. An example of this is shown when a strange person comes to the breeders house, puts them in a box and into a roaring creature with legs that go round and round (a car!!). They dont peck around happily, instead they make noises of alarm and worry what is going to happen to them. An even worse scenario is when they are stuffed into crates, loaded onto a lorry and brought to a slaughterhouse.  This is a terrible state for them to travel in, and they spend their time worrying what will happen to them.

The neocortex is the part of the brain that deals with complex thought. Chickens have one of these too.

An egg can only hold up to 200 calories, and many calories are needed for a big brain. This is why mammals go through the pain of childbirth, because they give their young a constant supply of calories, and their young grow a big brain. Despite possessing a tiny brain (about the size of a pea!!), chickens fit a lot into it. Their spinal chord, and some parts of the brain deals with movement, co-ordination and reflex, while the rest of the brain deals with memory, senses, future conceps and voluntary actions. This is quite a lot to fit into such a tiny brain!

Chickens Day by Day and month by month

Day To Day Chicken Practices

AM: let the chickens out, feed them (with layers pellet or mash), check grit, change their water and check for eggs.  Clean out the chicken houses if necessary. Dust with mite powder (red mite is a potentially deadly pest and can kill a full grown hen) and replace straw.

PM: check eggs ( essential if not done in morning) and feed chickens (with a handfull of grain) or (a top up of mash or pellets).

At dusk (or the earliest when the chickens go to bed) close their houses and count them.

CHICKENS MONTH BY MONTH

AM: let the chickens out,feed them (with layers pellet or mash), check grit, change their water and check for eggs. Depending on what day it is , clean out the chicken houses. Dust with mite powder (red mite is a potentially deadly pest and can kill a full grown hen) and replace straw.

PM: check eggs( essential if not done in morning) and feed chickens (with a handful of grain.
At dusk (or the earliest when the chickens go to bed) close their houses and count them.

February
If you are purchasing more chickens, now is the time to consider the breed you would like. Why do you want them? Eggs? For showing? Just for appearance? rare and traditional breeds often produce all these traits in one.

March
If you are purchasing more birds, you need to select a suitable house, with dark nestboxes, suitable perches, good ventilation and it must be large enough to accommodate all the bird comfortably.

April
Now is the perfect time to acquire your youngsters. Take a look all around the yard /farm /paddock where the birds are kept.
Do they look stressed? Have they got pale faces? Is the environment suitable?
If you think any hens look in poor condition do not go ahead with the purchase. If they all look good, you can make further considerations.

May
Make sure your new birds travel properly, make sure they don’t get stressed. This involves using suitable transport cages. Food and water should also be on offer, and overly long journeys should be avoided.

June
It is important to supply good food to boost summer production. Feed layers pellets, or mash and give grit. Greens are also important, they supply vitamins and minerals and cause egg yolk to be a rich yellow. Corn can be fed as a treat but do not overfeed as it can lead to overweight birds.

July
During the summer it is extra important that your hens have lots of clean fresh water AT ALL TIMES
During a hot summer hens can become overheated. Symptoms include panting, increased drinking, listlessness and lying on the ground panting.
If a chicken becomes overheated splash cold water on his or her comb and under his or her wings.

August
Look out for red mite (should be done at every time of the year) if you notice these grey (red after their first meal) pests then you need to buy red mite powder or spray A.S.A.P as these mites can kill a fully grown hen (luckily I have never experienced this through routine dusting of the hens, and the house.

September
Now the chickens are moulting, and replacing the old feathers with new winter ones. It is worth adding Apple Cider Vinegar (ACV) to their feed or water to give them a vitamin and mineral boost. This will help them stay healthy during moulting, which puts lots of strain on the bird.

October
If point of lay hens are still not laying they will begin in spring, or late autumn.
Reddening combs and wattles are signs to look out for when a hen is due to start laying.

November
Now is the time to prepare for winter using a suitable bedding as litter for the paddock, because otherwise you and your chickens will be squelching in the mud! Shavings are absorbent but messy, straw is even easier and does not absorb well, hemp is expensive and hard to find, but absorbent and it deodorises .

December and January
You may need extra warmth in the house, and ice needs cracking twice a day.
Keep feeding grit.
Throughout the year remember to close in the hens every night and count them. Check all ends of the hen house.

When I was a young girl, aged about six my job was to put the hens in and let them out, but eventually my dad started double checking because I once closed the front of the house, while leaving the back open and in the morning one hen was dead in the garden, one had been deposited in front of the door and the last had lost its head but was still half alive, and walked around with only a bloody, bent neck.

That taught me a valuable lesson.

Dutch Bantams

Dutch Bantam

The Dutch Bantam is a desired, ornamental breed kept by many chicken fanciers. ‘Bantam’ used in its common description is the wrong name because the Dutch are one of the few true miniatures as they are not a diminutive form of large fowl.
These upright proud little birds originated from the Netherlands but were soon exported to other countries. Recent DNA tests showed that Drente and Friesian fowl played a great part in the Dutch’s creation. They have a single well-serrated comb and the wings are long and carried close to the body. The ear lobes are white and the wattles are short and round. The tail of a cock has shiny green well-developed main sickles that are large and classically curved and the hens have fairly vertical tails carried upright giving them a U shape created by neck and tail.The Dutch Bantam lays quite large eggs for their size. Their egg producing capability is about 100-160 eggs a year.
Due to their size, Dutch females are only capable of covering a few eggs. Eggs take only 20 days to hatch instead of the usual period of 21 days for large breeds.

They come in lots of magnificent colours including gold partridge, silver partridge, yellow partridge, blue silver partridge, blue, yellow partridge, blue partridge, red shouldered white, cuckoo partridge, cuckoo, black, white and lavender.

Dutch bantams have a tame and trusting nature and make great pets.

Apart from the Dutch there are some other ‘true bantams,’ Sebright, Japanese, Antwerp and Belgians.