|Are You A Good Egg?|
How to tell if your egg is alive.
Published in BIRDBREEDER, October l996
Psittacine Breeding & Research Farm
Box 13, Point Arena, CA 95468 USA
PH: (213) 819-1723
I have always wanted to do this, so here goes: "Once upon a time", something greater than ourselves decided instead of having live birth, birds should be allowed to lay eggs. It is more convenient than carrying around a large abdomen and trying to fly.
Most of the time this arrangement with nature is just fine. I call it 100% perfect when I can get a hen to lay her eggs in her nestbox, incubate well , hatch and care for her own babies. There is a joy in knowing you will have the fattest, healthiest babies you can assist in producing for future generations to enjoy.
Of course this doesn't always work out 100% right. Some birds will just incubate and not feed the babies, others will just lay their eggs any old place. There are some macaws that I "bed down" their aviaries with a foot of fresh straw as soon as I know they are going to lay. I berm up the edges of the straw so if the egg bounces, and they will, they don't roll out of the chain link wire and get eaten by one of the guard dogs. I also remove any other obstacles to a straight drop down. You can retrieve these eggs unbroken, even from a drop of 4 or 5 feet. We keep working with these hens, and maturity seems to bring intelligence. Birds that last season just laid anywhere will now put their eggs in the nest, and others we can only hope will learn to incubate and feed their own offspring.
How do I know when they are getting ready to lay? With most of my macaw hens, their vents will start to enlarge, and their abdomens swell noticeably. The vent looks very soft and pliable.
I also keep good records for each pair, noting their habits each season.
I do incubate by hand those eggs that need human attention. I realized, after trying to explain how to candle an egg over the phone to my mother, that it is almost impossible to convey all the intricacies a person needs to know without showing them in person. Sketches are a good second. There are ways to tell if an egg is fresh, alive, and/or about to hatch.
I should hope that at this point you have either purchased or made an egg candling unit. If you haven't done so, here is an easy way to go about it. First, you can go to a local feed store, and get a commercial egg candler used for domestic fowl. The drawback on this is that is a little too big for parrot eggs, and you have to handle them. It does give you the best visual that you can get. Use uncontaminated rubber gloves to handle the eggs. You could look in the index of advertisers for Robbie Harris's Candling Without Handling unit. It is a wand with a high intensity light at one end, battery operated. It is harder to see if you are trying to stick your head in a nest barrel, along with an arm and the candler. You could be being chewed apart by macaws or cockatoos at the same time trying to fend them off with a candling wand. Seriously though, the only drawback we noticed with this wand is with the large birds, this can easily be snapped in half. This is easily adapted for large birds by sleeving it with a piece of PVC pipe. The last alternative is to take the shade off a lamp, hold up a piece of cardboard in front of the bulb, with a hole cut out in it. Whatever you use, don't cook your egg. Look quickly. Please remember these bulbs are all HOT and can easily coddle your egg. It is also advisable to have a good magnifying glass available. A data base of species-specific egg weights and egg weight loss charts would be helpful, but those are not readily available and could show variations that would cause confusion for someone trying to make generalized comparisons with their first eggs.
I encourage people to keep data on everything they do with birds, and share that data. A typical weight loss chart would show the beginning weight of a fresh egg, a calculation for 16% weight loss over 28 days, and daily weights to maintain a development/humidity ratio. It would also show the weight of the infant when hatched, and the weight of the used shell (including shed membranes) just after hatching. Here are some other ways to tell if your egg is "good"!
FRESH EGGS; chicken eggs are the easiest to use as a guide, if you can get some from a farmer somewhere. Store bought eggs are dipped in waterglass and stored for great periods of time, so would never be as reliable for purposes of demonstration. It is interesting to see how fresh store-bought eggs are, so if that is all you can find use those. Fill a bowl to a depth of 4 inches with warm ( 98 degree fahrenheit) water, and gently set the egg in. A fresh egg will sink to the bottom, and a not-so-fresh egg will float. This is because of the variable size of the air cell in the large end. An air cell can be large because an egg is old and just drying out, or because the embryo inside is developing and the cell is getting larger as a reflection of that developme
Now candle that egg. If the egg floats as "old", or "developed", and you cannot see through the mass of albumen and yolk to determine what is inside, there are more tests. Of course if you can see through the egg and the yolk is clearly visible and it floats, it is just old. It is also possible to see an embryo as it develops , at least for the first 13 days.
There is another way to judge an egg with a large air cell and a dark mass whose makeup cannot be determined. Refloat the egg in warm water that is very still, and watch the egg for a few minutes and see if it moves. An embryo late in its development is moving quite a bit (when it is not resting) and you will see the slightest twitch as movement in the water. Immersion in water will not harm the embryo, just don't coddle it or leave it in more than about 3 minutes. If water makes you nervous, lay the egg on a very flat plate ( I just turn the plate over and use the plate's foot for a berm) and watch for movement. It can rock easily; it will if it is alive.
If after all this you are still not certain, place it back in the incubator, treat it as if it were alive, and check it again in a few days. That will give you time to think about the egg, and not make a hasty decision. I always recommend leaving an egg for at least 10 extra days incubation if there is a question.
Even pros make mistakes. We live outside a small town, and several years ago someone who raised lots of chickens disposed of a few boxes of" outdated" eggs at the county dump. The weather was warm that night, and the next morning there were lots of little chicks running around the dump. People were there all day gathering the little chicks. How embarrassing for whomever dumped the "undercounted" eggs! I have also spoken to persons who have opened their macaw eggs at the 28th day, and have actually killed their own embryos. Hatching takes lots of time, and patience. After all, most of us wait for years to get those eggs - so what is another couple of days!! Another illustration: my most prolific pair of Blue & Gold Macaws had laid three eggs, just at the three-day intervals, and hatched all three. I left the babies in for three weeks, and then, with the assistance of Geoff, removed all the babies at once for handfeeding. I scooped up the smallest and the largest one, and handed them to him. Then I scooped up themiddle one--and sticking out from between my thumb and finger in my left hand was this tiny little head! There was another baby, by his development he was about 10 days younger than the youngest of the three birds. Always remember that with birds, you have guidelines, but no rules! Happy hatching!
|© 2019 Parrot Preservation Society - Founded by Barbara & Geoffrey Gould, Operated by Christine Gould|