Reproductive Disorders

The reproductive lifespan of birds varies according to the species. Some Congo African greys are still producing at 40 and laying infertile eggs at 60 years of age. Greg Burkett reports an African grey which laid its first egg at over 20 years old. He has also had some cockatiels over 20, greys over 25, a macaw over 30, and an Amazon over 50 who have all laid eggs.¹⁰ Dr. Dahlhausen has had in his practice a scarlet macaw that laid her first egg at the age of 95! (R. Dahlhausen, personal communication.)

There have been many studies of the effect of aging on reproduction, primarily in domestic poultry. "There is a definite decline in fertility and reproductive/hormonal behavior as the bird ages, and clutches decrease in number and frequency. There is also a decrease in the viability of the young. The ovulatory cycle and spermatogenesis (sperm production) both cease." ^10,62In a study of macaws in Parrot Jungle and Gardens in Florida, the oldest birds to successfully breed were 35 years old; but generally, reproductive activity declines in the twenties to thirties. Dr. Burkett states that budgies are able to reproduce much later in their lifespan compared to other species, and most birds live at least one-third or more of their total lifespans after reproduction ceases.^10,62

17.1 Infertility

Older breeders tend to become obese, and that is one of the primary factors in infertility. They also tend to suffer from the effects of:

• Inbreeding
• Damaged vent feathers
• Drug therapy, causing vitamin deficiency
• Previous hormonal therapy (testosterone injections)
• Previous musculoskeletal, neuromuscular conditions or other diseases which may be causing pain and weakness
• Decreased muscle tone or incoordination
• Neurologic disease, which may cause paresis and ataxia (lack of muscle control)
• Natural, direct, decreased fertility and reproductive-tract disease
• Nutritional deficiencies or excesses
• Systemic disease
• Parasitic disease leading to malnutrition
• Cloacal abnormalities or abnormal cloacal pH
• Possible thyroid deficiency³⁵

17.2 Reproductive Disorders in the Older Psittacine

Many older female birds become egg-bound because they are laying their first egg late in life. These eggs are usually larger than normal and are difficult to lay. This becomes an emergency situation because the "huge egg is putting pressure on the kidneys, causing shock. Hormone levels go abnormally high and may be caused by cystic ovaries which may stimulate the bird to start laying eggs. Polyostotic hyperostosis (POHO—an abnormal amount of calcium deposition in multiple bones), may also be present." ²⁰ Adjusting the light cycle and administering leuprolide acetate injections or Deslorelin implants often help to resolve this condition.²⁰
 

17.2.1 Late Hatch

Late hatch can be attributed to the old age of the parents, according to K. Joyner. "If ovulation ceases suddenly due to trauma or stress, then developing follicles may hemorrhage, resulting in regression of the developing follicle. Aging hens can exhibit permanent ovarian involution (a progressive decline or degeneration of normal physiological functioning occurring as a result of the aging process), which is believed to be a normal physiological process." ³²

17.2.2 Cystic Ovarian Disease

Cystic ovaries may occur alone or with other conditions, such as egg-yolk peritonitis and ovarian neoplasia. Other diseases which affect mature reproductive hens and senior hens include peritonitis, egg-yolk stroke and oviductal prolapse. "It may be asymptomatic or be accompanied by symptoms such as abdominal distention and dyspnea due to the pressure within the abdominal cavity. Removal of the fluid that has built up may relieve the discomfort. Leuprolide acetate has been used to stop production of ova." ³⁷ Diagnosis is by radiology or ultrasound.
 

17.2.3 Cloacal and Uterine Prolapses

According to Bob Doneley, cloacal and uterine prolapses are caused by:

• Excessive straining
• Masturbatory behavior in male cockatoos
• Sexual overwork
• Oviductal disease, such as:
  • Egg binding
  • Salpingitis
  • Intra-abdominal pressure
  • Cloacal diseases such as cloacoliths (solid masses of debris) and cloacitis (inflammation or infection of the cloaca)
  • Internal papillomas
  • Internal papillomas
  • Constipation or diarrhea¹⁵

In geriatric birds, prolapses are generally found in the females and are related to loss of cloacal muscle tone due to chronic trauma from excessive breeding, difficulty in egg-laying, and retained and laying of soft-shelled eggs over the lifetime of the bird.¹⁵

"The bird presents with a protrusion of the cloacal mucosa (with or without rectum or oviduct) through the lips of the vent. The prolapse is usually accompanied by straining and grunting while the bird is defecating, and she may pass blood around the vent or in the droppings." ¹⁵ If the prolapse is not treated immediately, the tissue may be filled with fluid, and necrosis can result. To treat it, the practitioner will reduce the prolapse and place it back into the cloaca. If the cause is not found and dealt with, prolapses will probably recur. ¹⁵