Lay Lady Lay!

Saturday, July 6, 2013

The Incredible Egg and What Triggers your Hen to Lay It

Yay! The shortest day has past and from now on the days will be lengthening out and delighting us with more daylight hours.

It is the increasing daylight hours that will trigger your pullets and hens into the lay. Roll on spring. Age of course is also a factor. For pullets in the heritage breeds point of lay (POL) can be anywhere around 24 to 32 weeks or longer for the slower maturing breeds. It is also important to bear in mind when your pullets were hatched during the season. In our experience those hatched out early in the season (June/July) will come into the lay in late summer (January/ February) whilst those hatched out from November onwards will often mature in late autumn. These late hatchers will wait till the days start to lengthen and think about laying late winter or early spring. The commercial hybrids on the other hand are programmed to be laying machines. They are designed to come into lay around 18 to 24 weeks depending on the season. We have found daylight hours do impact to some extent on when they commence laying. Those that are POL when the length of the day is long (summer) come into lay sooner around 17 to 18 weeks and winter POL birds are usually later around 22 to 24 weeks

There is a pea-sized gland inside the brain of our chickens called the pituitary gland. When the chickens eye perceives increased daylight it does not go unnoticed by the pituitary gland. This controlling gland is then stimulated and produces a hormone that is carried via the bloodstream to the ovary which sets egg production in motion. So as the longer days arrive with more sunshine and warmth so the laying gets underway. A hen lays eggs during daylight hours, typically between 7am and 4pm, producing no more than one egg about every 25.5 hours. 

Chickens need 12-16 hours of light, either natural or artificial, to produce consistently. One reason why chickens lay eggs less frequently in the colder months is that there are a fewer number of daylight hours. Through the winter, heritage poultry have normally no interest in breeding. There are good reasons for this because, in the wild, the reduced day light, general lack of food and cold weather are not suitable conditions for breeding. Most birds also go through the moult during this time, this period of rest is important to replenish reserves and prepare for the new breeding (laying) season ahead.

Chickens can live for many years and continue to lay eggs for many of these years. However, after two or three years many hens significantly decline in productivity. This varies greatly from bird to bird. Good layers will lay for about 50 to 60 weeks and then have a rest period called the moult. Even commercial hybrids after their first season of lay (12 months) will show a drop off in production and undergo a partial moult.
Here at Appletons we dont light up our hen houses and pressurise our girls to lay all year round under artificial light. We let nature take its course; so as we all wait for the daylight hours to lengthen, we thought we might egg-cite you with a few interesting things about the humble egg and the magical hen that lays it. Plus we have added into the mix some classic questions we have been asked about eggs over the years.

How is an Egg Made? 

Chickens are amazing! When your hens are laying well, they will produce a new egg every 25.5 hours. This is a very short time to create something as complex, as perfect and as tasty as an egg. An egg is made from the inside out. The yolk is made first, and then wrapped in a layer of egg white, before being neatly and beautifully packaged up in an egg shell. The beginning of an egg is the tiny ova which takes a week to grow into a proper egg yolk. If you cut a boiled egg in half and look at the yolk, the dark rings were layers made during the day and the light layers during the hours of darkness. When the yolk is ready it is released along the oviduct. The first part of the oviduct is where the egg white (albumen) is added. The egg white mainly consists of protein, water and minerals. Then the egg carries on along the oviduct where it grows two connecting strands at the top and the bottom called chalaza, which anchor the yolk to the shell keeping it in the centre of the egg. The next stage is for the shell membranes to form around the white. After this the egg continues down into the uterus where the shell is added. The shell is made from calcium carbonate. The shell is a great bit of design, it is on average only 0.3mm thick but it is incredibly strong. The colour of the shell depends on the breed of chicken and on the individual chicken itself. Some hens lay white shelled eggs like the Dorking and the Araucana lays a blue shelled egg, but the colour of the shell doesn't affect the taste.

How Does a Hen Lay her Egg?

As a rule, chickens lay in the morning, but each day a little later. Sometimes the last egg of a series is produced in the early afternoon. When it gets too late, they take the next day off. That is why on some days we do not get an egg from each hen.The hen approaches her chosen nesting spot in a very determined yet hesitant way, and finally enters. There she gets comfortable and sits quietly for a long time, often for half an hour or more. She closes an eye, can chat quietly to herself and possibly re-arranges the shavings, and then finally she gets more exited. Now and then, the hen raises her tail and spreads the feathers of her bottom.

These movements increase gradually. Under her tail, between the feathers, is a small opening with a ribbed rim called the vent. Suddenly the hen stands up with her feet wide apart, tail raised, bottom feathers spread out, and back feathers upright. As her vent opens a little, you begin to see a red membrane. As the hen lowers her bottom, her vent widens rapidly and the rim is stretched further. The membrane forms a pinkish dome around the egg which is not yet visible at this stage. The vent is now wide open and the ribbed rim has become narrow and far stretched. Through the opening bulges a pink hemisphere of tissue revealing distinct blood vessels. Its top is pointed downward where a new opening arises. The egg appears as a much lighter-coloured disk. The hen strains at intervals. Each time, the egg protrudes a little further out. As it does, the membrane opens to form a red collar around the wider, middle portion of the egg. The membrane will protrude a little ways from the ribbed rim. The moist egg pops out.

1. Ovary, 2. Infundibulum, 3. Oviduct, 4. Magnum & isthmus, 5. Uterus, 6. Cloaca

Sometimes it will come out blunt end first, sometimes pointed end first. For a few seconds after the egg is laid, a small red cone still remains outside, but it is retracted almost immediately and the vent is closed again. The bird stands high above the egg and rests, beak open and panting after her heavy work. The entire process (from rising to dropping the egg) is quite fast and is finished within half a minute. Therefore, it is hard to observe. After a while, the hen looks back, inspects the egg with her beak and leaves the nest under a loud series of cackles.

Why Do Hens Leave the Nest After Laying? 

All chickens lay eggs in a series - never more than one per day. If the eggs are not collected, and a sufficient number of eggs are allowed to collect in the nest, the hen may eventually stop laying and start brooding. When the hen leaves the nest after laying an egg, it cools which suspends the development of the embryo inside. This egg and the rest will not develop until the hen takes up residence 24/7 on her nest and starts her brooding. Her body heat coupled with moisture from her skin and the instinct to turn her eggs will hopefully prove fruitful and result in newly hatched chicks 21 days later. So the idea is all eggs commence development together and hatch together (usually within 48 hours of each other). This is why it is important for the hen to leave the nest after laying because if she went broody when she first started laying then theoretically all her chicks would hatch a day apart and she would leave the nest with the first few hatchlings and abandon the rest. Isnt nature wonderful!

Why Does a Hen Cackle After Laying her Egg? 

The ancestors of our domestic fowl are the jungle fowl and they were and still are forest dwellers. They live in small family groups called flocks. They scratch under the canopies in the leaf litter and forage for invertebrates, bugs, worms and berries to eat. When a hen goes to lay her egg in the nest the group may wander away through the undergrowth searching for food. The hen's cackle serves to renew the contact with the group as if to shout "where are you? The rooster (with the other hens) would answer "here we are! Our chickens like their ancestors still cackle today.sometimes we suppose proudly adding to their call Wow you should see the whopper I laid today!

Are Eggs from Hens on Free Range (pasture) More Nutritious? 

We all know the eggs from our grass-eating, pastured hens taste better, but are they really better for us than supermarket eggs? The folk at Mother Earth News have been compiling nutritional data on eggs from hens who feast on pasture - fresh grass, bugs, and all the goodness they find outdoors - and the results are exciting for anyone who raises laying hens.They report that their tested eggs contain:

1/3 less cholesterol
1/4 less saturated fat
2/3 more vitamin A
2 times more omega-3 fatty acids
3 times more vitamin E
7 times more beta carotene than their supermarket counterparts. Their most recent round of testing focused on vitamin D content, which they found was 4 to 6 times higher in eggs from free range hens than from supermarket eggs

What are Carotenoids? Are Deep, Orange Yolks Healthier than Pale Yellow Yolk?

The colour of the yolk is due to substances called carotenoids. The nutritional value of the egg is not affected by the yolk colour. The most important sources of carotenoids in poultry feed are maize (corn), maize gluten, alfalfa (lucerne) and grass meals; these sources contain the plant pigmenting carotenoids lutein and zeaxanthin, which, together with other oxygen-containing carotenoids, are known by the collective name of xanthophylls.When hens are able to eat green plant material or yellow maize the beta carotene concentrates in the yolk making it dark sometimes even orange. Poultry raised on fresh pasture instead of stored grain get more unsaturated fats and vitamins in their diets. Its like the difference between fresh and canned vegetables... Lutein and zeaxanthin have been shown to reduce the risks of cataracts and age-related macular degeneration, the leading cause of blindness in those 65 and older.

 Research has shown that, due to the egg yolks fat content, the yolks lutein and zeaxanthin may be more easily absorbed by the body than the lutein and zeaxanthin from other sources. A large egg yolk contains 166 mcg of lutein and zeaxanthin.

Carotenoids dont just put colour into egg yolks; they also perform vital functions. In the egg, they protect sensitive substances such as vitamins from becoming "rancid", and protect every single cell from harmful influences. Hens, too, profit from carotenoids in their feed: their immune systems are strengthened, protecting their cells from harmful environmental influences and providing the basis for vital vitamin A. When it comes to mother hens chicks, healthy birds only hatch if the yolks are provided with sufficient carotenoids. These carotenoids also help to brighten the leg colour of yellow legged free range fowl. Poultry that have daily access to pasture and greens will have more intense yellow legs than their penned counterparts.

Why do Commercial Poultry Feeds Contain Egg Colourants? 

We like our yolks to be a deep yellow or orange when we serve them on a plate. However, the carotenoid content in the ingredients of poultry feed is not constant; the pigmentation properties of the carotenoids can be weakened or lost in a variety of ways. These fluctuations in carotenoid content and availability concern both the poultry nutritionist and the feed producer. Because of such fluctuations, naturally-occurring carotenoids cannot be relied upon to provide the desired yolk colour or to provide a consistent colour. Therefore, nature-identical yellow and red carotenoids, such as apoester and canthaxanthin, are commonly added to feed in order to achieve the desired egg yolk colour. Consumed by the laying hen, these supplemental carotenoids are readily transferred to the blood and then deposited in the yolk to provide pigmentation.

How Long Does an Egg Stay Fresh? 

The NZ Food Safety Authority recommends a shelf like of 21 to 35 days for eggs from date of lay depending on storage conditions. The eggs we collect from our backyard chooks are best left unwashed and stored in a cool place or in the refrigerator (bottom shelf and not in the door).

But can they be stored for longer? Squirreling eggs away for long term storage can be a very good option for those of us that are prudent and dont wish to purchase supermarket eggs when our own hens are not laying. The conclusion of a seven month study undertaken by Mother Earth News was that unwashed, fertile free range eggs from backyard flock seem to store much better than washed, infertile supermarket eggs. Why? Probably for the simple reason that they're unwashed and not because they're fertile. When a hen lays an egg it is coated with a light layer of a natural sealing agent called a bloom. And, while a good wash may make a batch of eggs look more attractive, it also removes this natural protective coating leaving the eggs more prone to aging and contamination. The very best way to store eggs long term is in a sealed container at a temperature of 2 to 4 degrees Celsius.

The popular idea of preserving eggs with a solution of one part water glass (sodium silicate) mixed with nine parts of boiled and cooled water does indeed seem to work better than any other room temperature preservation methods tried during the study. It was concluded that this method is good for about five months and is a distant second to controlled refrigeration. We recommend testing all eggs prior consumption break each egg separately into a glass or cup prior to adding to baking or cooking.

Why is it Hard to Peel the Shell of Hard Boiled Eggs? 

This usually tends to happen with very fresh eggs. A hard-boiled egg will peel more easily if it is a week or two old before it is cooked. To tell if an egg is raw or hard-cooked, spin it. If the egg spins easily, it is hard-cooked, if it wobbles, it is raw. A greenish ring around a hard-boiled egg yolk is due to either overcooking or high iron content in the cooking water. This can be avoided using proper cooking time and temperature, and by rapidly cooling the cooked egg in a bowl of ice-water for a few minutes.

How do I Tell a Fresh Egg Over a Stale One? 

A fresh egg will sink in water, a stale one will float.

Why is an Egg White Sometimes Cloudy?  

Cloudiness of raw white is due to the natural presence of carbon dioxide which has not had time to escape through the shell and is an indication of a very fresh egg. As an egg ages, the carbon dioxide escapes and the egg white becomes more transparent.

 I only want to hatch out hens so can I just have the girl eggs?

Dont laugh this is a question we get asked frequently! If only we could sex eggs we would be multi-millionaires and we would change the face of the poultry industry! Generally speaking when purchasing fertile eggs for hatching the sexes across the season works out at a 50/50 ratio. So for all the hatches done over a 9 month period the number of boys to girls is about equal. Saying that, each hatch can vary and it is not unheard of to end up with all cockerels or all pullets. There are all sorts of myths about pointy ended eggs, swinging rings on chains and temperature that can predict sex but we have found no truth in any of them.

My hen is pregnant (all round, fluffed up and sitting in the nest box) can I get her an egg to sit on?

A hen is technically never pregnant as she does not give birth to live young. When she is all round, fluffed up and sitting in the nest box she is in a state of broodiness. She has laid her clutch of eggs (which you have probably collected and eaten over the past two to three weeks) and now she is ready to incubate them for 21 days so she can raise a family. She will usually sit on a setting of eggs as this will give her a good chance at successfully raising a decent number of the next generation to maturity. For a standard size hen a setting of eggs is usually a dozen.

So lets do the maths. Mother hen is sitting on 12 eggs. Day 4 one rolls out and gets cold. Day 16 a hedgehog rolls two out for his dinner (yes it happens hedgehogs are regular egg thieves and rats too) Hatch day and 3 dont hatch (one was clear, one died during development, one gets stuck hatching) So 6 chicks are out. One chick leaves the nest and does not get back under mum for the night so it dies of the cold. Five bouncing chicks left under proud mum. All doing well till 4 weeks old then the neighbours cat gets one. Four left.Lets have a go at sexing them at 6 weeks two are cockerels and that leaves 2 pullets. So the moral of the story is it is best to set a decent number of eggs under your broody for the best result. ps. Please do not ask us for one egg!

What was first, the chicken or the egg? (yes had to add this one!)

Short answer: the chicken is the eggs way of creating another egg.

Do Fake Eggs in the Nest Box Encourage Hens to Lay? 

Here at Appletons we use fake eggs (we like the wooden ones) to encourage our girls where to lay. When POL pullets get ready to start laying place a couple of fake eggs in one of the nest boxes to show them where to lay. This will give them the idea that the boxes are "the place" to lay their eggs. Hens are often visit the nest boxes that eggs and hens are already occupying.


Have enough nest boxes.
One box for every 5 hens is the general rule of thumb. Chooks like to share laying boxes so it is not necessary to allocate a box per chook.

Make nest boxes private and appealing.
Ensure that your nest boxes are in a dark, quiet corner of the coop. Hens have the instinct to lay their eggs in a safe space. Boxes should be raised off the coop floor and preferably secluded. Sometimes a partial curtain over the nest box entrance for added privacy can make a big difference. We use thick black plastic sheeting and staple this over the nest box entrance. We then cut a v shape at the entrance to the nest box and cut the rest of the curtain into strips. This gives the hen a peek-a-boo hole to enter with the easy option of pushing out again. The black plastic can be easily removed when cleaning, re-stapled and reused.

Make nest boxes comfortable.
Line them with soft, untreated wood shavings. As the hens frequent them the shavings get depleted and hens tend to avoid them. The eggs are also more inclined to get broken. So refresh regularly with shavings.

Gather eggs early and often.
Best to collect eggs daily or if you can manage it collecting in the morning and late afternoon. Twice a day collection ensures clean eggs, and also discourages dirty, broken and eaten eggs.

Keep nest boxes dry and clean.
If there is chicken poop in the nest boxes remove it when collecting the eggs and replace with fresh shavings. Likewise, if a hen has broken an egg, clean up the mess quickly and thoroughly, removing all wet or soiled shavings. Broken eggs if ignored can lead to egg eaters and egg eating is a learned behaviour and very hard to break. Usually the best solution to stop egg eating is to dispatch the culprit.

Appletons tip to discourage hens sleeping in nest boxes
Here at Appletons we recommend when you first bring your young perching pullets home and settle them into their new hen house remove the nest boxes or cover the nest boxes with a piece of cardboard. This will stop the young pullets huddling in the nest boxes or roosting on the edge of them. If they only have the perch available then they will roost on the perch. Once pullets have got into the habit of roosting on the perch they will return to the same spot each night. At POL uncover the nest boxes, fill with shavings and add a pair of fake or brood eggs. For naughty hens that persistently foul the next boxes we recommend covering over the nest boxes at dusk and physically placing the hens on the perches. This might need to be done for a week or so until the hen/s gets the hang of it.

Nutritional EGG Snippets

The incredible egg has a high nutrient density because it provides a wide range of nutrients in proportion to its calorie count (about 70 calories per large egg). Nutrient-dense foods help you get the nutrients you need without excess calories.
A large-sized egg supplies 12.6% of the Daily Reference Value (DRV) for protein. A little over half of the eggs protein is in the white and the rest is in the yolk. The eggs protein is the highest quality protein of any food. One egg of any size equals one ounce of lean meat, poultry, fish or seafood in the food groups.
High-quality protein, like the protein in eggs, can benefit people of all ages in many ways, including forming muscle tissue, building muscle strength, repairing muscles after exercise and warding off the loss of muscle tissue as we age.
Egg yolks are an excellent and important source of choline. A large egg yolk contains 125 mg of choline and provides 23% of a pregnant womans daily needs. Choline intake during pregnancy may be a key factor in the development of infants memory functions and, later in life, choline may improve memory capacity.
Eggs are also a good source of vitamin B12 (10.8 % of the DRV) and riboflavin (14% of the RDI) and supply varying amounts of many other nutrients, including a wide variety of other vitamins and minerals. The yolk contains a higher percentage of the eggs vitamins than the white, including all of the eggs vitamins A, D and E. Egg yolks are one of the few foods that naturally contain vitamin D.

On that nutritional note, we wish you all a good winter and keep feeding your chooks well. Remember feeding your birds a complete nutritionally balanced feed containing animal proteins will provide your girls with all they need to lay incredible eggs. Happy, healthy hens are productive hens!