Birdsafe California Bird Nerds

Light and hormones drive egg laying

I have a maroon-bellied conure, and she never lays any eggs. Is that normal?

-- Nicole,

My 10-year-old green-cheek conure laid six eggs last year, which worried us as she wasn't acting too well. We took her to a vet who told us she needed a hormone shot as she was too old for that many eggs and could get egg bound. After the shot, she got so sick we thought we were going to lose her. She got very lethargic, droppings were very watery and she got very bloated. Vet said she was too fat and had us put her on a diet. We took her back to the vet three more times, but he said it was a normal reaction to the shot. It took her two months to get well and we blame it on the shot. We had been told to take the egg away immediately after she laid it to keep her from laying more. Since, we have heard otherwise. A week ago she laid three eggs which we left with her for most of the day, till she seemed to ignore them. She stopped at three and is fine and healthy as normal. Seems that leaving the eggs was the right thing to do. It's been two weeks since the last egg and she's well, happy, and playful as ever.

-- Al Judd,

Last August my husband and I retired and moved to Florida from Atlanta. Our 15-year-old female gold-crowned conure has been laying eggs in the summers for the last five or six years. However, in Florida she started laying eggs in November and continued through New Year's. I found an article on the Internet that said exposing birds to extended periods of light could trigger laying. The room the birds now have had three large overhead flourescent lights. We disconnected two, but laying continued. We turned the lights off entirely and let natural daylight govern the birds' day and night. The egg laying stopped immediately and has not recurred. Would fluorescent lights have caused our conure to lay?

-- Carol Martin,

My budgies sometimes lay eggs. When they do, I give them the liquid calcium supplement neocalglucon in their water (1 cc per 30 cc's). I just tried to purchase some and found that it is no longer manufactured. What can I use as a substitute? They have mineral blocks and cuttle bone, get fresh greens every day and pellets are a big part of their diets. I have one hen, though, who won't touch the cuttle bone or mineral blocks and I would like to know that she's getting enough calcium.

-- Judy Judd, New York,

Egg production is the most stressful event in a bird's life. It's been estimated that 10 percent of all hens have reproductive problems annually.

Some pet birds never produce eggs; others lay to excess. Many things can stimulate a hen to lay - the season, lighting, hormones, presence of a mate. Removing eggs will usually result in more being laid. Letting a hen sit on them will usually "turn off" the ovaries and stop egg production.

Hormones are very powerful chemicals produced by specialized glands of the body. In addition to sexual activity, hormones control metabolism, mineral balance, growth, and other natural processes. The pituitary gland stimulates a hen's ovaries to produce egg yolks. By giving a bird hormone shots that combine a variety of drugs such as chorionic gonadotrophin, Luperon, and steroids, it's possible to shut down the pituitary and stop egg laying.

I've never seen a hen bloat from a hormone injection, and such a reaction is not something I can explain. However, I would agree with you that attempting to control laying via medical means can have adverse effects. Manipulating your bird's environment is the safer way to go.

One of the stimulators of the pituitary gland is light. In fact, birds' skulls are so thin, light literally shines through to this gland. Normally, in most species as the daylight hours shorten, the pituitary shuts down production. As daylight hours lengthen again, the pituitary resumes activity and breeding begins.

You should be able to stop your bird from laying by shortening the period of light she's exposed to each day to six hours. Completely darken the room the rest of the time - if the cage is small enough, you can place it in a well-ventilated closet, if necessary.

You should also remove your bird's favorite "loveys" and, if there's a mate, relocate him far enough away that he and the hen can't hear one another vocalize.

If egg laying continues and causes serious health problems such as egg binding (a life-threatening condition in which the bird is unable to expel the egg), you should speak with your veterinarian about the possibility of surgically removing the uterus.

Cuttlebone, mineral block and the foods you mention, plus dairy products and crushed eggshell, all are rich in calcium, necessary for the laying bird. Alternatively, your veterinarian should be able to provide you with liquid forms of calcium.

Keep in mind that birds need vitamin D3 in order for their digestive tracts to absorb calcium. Birds exposed to at least a few hours of unfiltered sunlight (light through the windows doesn't count) a day will produce their own vitamin D3. Birds confined indoors need vitamin D3 added to their diet via fish oils or commercial vitamin supplements.

Dr. James Harris James Harris, DVM is owner and medical director of the Mayfair Veterinary Clinic in Sandy Bay, Tasmania, Australia. He founded Montclair Veterinary Hospital in Oakland, Calif., and has served as medical director and chairman of the board for the International Bird Rescue Research Center in Berkeley. Dr. Harris' numerous professional honors include California and National Bustad Companion Animal DVM Awards. Copyright 2010. All rights reserved.

Return to current Ask a Vet column

  Bird clubs.
  Bird rescue groups.
  Find an avian vet.
  Parrot FAQ

California Bird Nerds Lafeber