By: Pat Tucker
(All Rights Reserved)
Hand-rearing is a demanding, time-consuming process which is undertaken by the aviculturist:
* to raise offspring hatched from artificial incubation
* to save sick or abandoned young
* to reduce the burden of parental care on compromised parents.
* to encourage production of a second clutch
* to prevent transmission of disease (0ther than transovarian)
from the parents
Neonatal Development & Problems in the Nest: Upon hatching, a cockatiel chick is not capable of thermo-regulation and must be brooded constantly by the parent for the first two weeks to ensure survival. As a result, nest inspection often reveals an aggravated, fluffy parent who refuses to budge off eggs and babies. Oftentimes, hatching must be determined by the presence of begging and feeding sounds emulating from the nest. To avoid injuries, further interference is not recommended unless problems are suspected. A new hatchling may not be fed until the yoke sac is thoroughly absorbed, which may take up to 12 hours, however, it is most common to hear feeding sounds within an eight hour period. Constant begging which is not followed by the usual feeding sounds is a clear warning sign and should never be ingored. To assist the parents with the strenuous feeding schedule, nestling foods such as warm cooked vegetables, rice, beans, and egg foods should be offered during the early weeks of chick development in addition to the regular diet. The parents swallow food, partially digest it using enzymes in their crop and regurgitate the food to the chicks. During this process, gram-positive bacteria is also transferred to the chick to promote proper functioning of the gut, protect against infection, and help synthesize certain nutrients. As a result, it is best to leave the chicks with their parents for at least a week (preferably 2-3 weeks) before pulling them for hand-feeding.
Problem areas during the nestling stage include insufficient feeding, rejection, quill-pulling, and mutilation. Fostering is usually successful to a nest of the same species whose chicks are in the same developmental stage. In the cases of rejection or mutilation, pulling the chick immediately for hand feeding is recommended. However, in a large brood where the youngest chicks are not being fed adequately, supplementary feedings in the nest usually prove satisfactory providing the parents will tolerate the constant intrusions.
Formulas & Feeding Methods: There is a distinct advantage to allowing the natural parents to rear their own young for the first 7 days. Species-specific normal flora is regurgitated in the crop milk and established in the alimentary tract which ensure a strong immune system and a healthy chick. No human foster-parent, even with the scientifically-formulated handfeeding diets available on the market today, can match this normal flora. Chicks pulled for hand-feeding at 7-10 days, however, and given a lactobacillus product in their hand-feeding formula rarely experience health complications traced to the absence of normal flora.
There are two basic methods of handfeeding: "Adlibitum" and Gavage. "Adlibitum" is Latin meaning "to the desire" and utilizes the chicks natural feeding response by depositing only the amount of formula desired by the chick. The spoon, syringe, eye dropper or pipette is recommended for this feeding technique, and is preferred to gavage feeding since it simulates the natural feeding method of the parent bird.
During this method of feeding, the instrument is inserted into the left side of the beak angled toward the esophagus (which is located on the right) and the formula is released slowly as the bird's head 'chugs' back and forth using the chick's natural feeding response. To stimulate the feeding response, the thumb and fore-finger should be placed on the pads located on either side of the upper mandible just below the cere.
Gavage feeding, on the other hand, deposits the formula into the crop using a feeding needle or a catheter tube without initiating the feeding response. Because of the possible dangers associated with this technique, this method of feeding is not recommended for an inexperienced feeder since the feeding tube or needle is actually inserted into the mouth of the esophagus and down into the crop so that the formula can be released quickly.
Housing & Management Techniques in the Nursery: The age of the nestling and amount of quilling will determine the environmental conditions required in the nursery. During the early weeks, electric brooders which are thermostatically controlled with circulating air and humidity regulators are preferable.
The temperature should be set at 85-90 degrees F. during the early quilling stage. This can be accomplished in an electric brooder or a fish tank with a heating pad placed underneath. Wrap the heating pad in a towel to prevent potentially lethal burns should the baby burrow through the bedding and come in direct contact with the bottom of the tank.
If a make-shift brooder is used, place a room thermometer inside and regulate the temperature for at least 24 hours before pulling chicks from the nest. (Note: If a chick pants, reduce the temperature immediately.) As the chick begins to feather out, the temperature can be gradually reduced. Relative humidity should be kept at 50% or slightly above for chicks under 4 weeks. When chicks are completely feathered, a temperature of 75-80 degrees F. is sufficient and weaning foods should be offered. Once the chicks are fledged and are actively weaning, the chicks can be transferred to a cage and solid food and water offered.
Hygiene: Since harmful bacterial, viral and fungal agents are present in our bird's environment, and as aviculturists, one of our main responsibilities to our captive flocks is to keep these hazards to a minimum through strict hygienic controls. Handfeeding utensils and formula mixing containers should be cleaned vigorously and soaked in Virkon-S, or other appropriate non-toxic solution between feedings. Clutches should be housed individually and a separate batch of formula and a separate feeding utensil should be used for each clutch. In addition, hands should be disinfected between clutches.
Chick Development: Since cockatiels are altricial birds born naked and helpless, chick development is a slow, progressive process requiring specialized care. Chicks are hatched with an over-developed hatching muscle at the neck, an egg tooth located at the tip of the upper mandible and a sparse hair-like down, either white or yellow in color.
During the first two weeks of development, the hatching muscle atrophies, the egg tooth gradually disappears, but the thermo-regulation by the chick remains poor. As the chick develops, eyes open, quills appear at the head, wing and tail area and thermo-regulation improves slightly. The chick elevates his head while pushing upward with his legs and wing during feeding..
By the beginning of the third week, uncoordinated preening activity is observed. Quilling fills in on the back and underside, with the exception of the crop area. There is an increased awareness of external events, and exercise such as walking and stretching are observed. Active preening results in removal of the feather sheaths revealing the beautiful feathers of a healthy baby cockatiel, and thermo-regulation is good at this stage of development.
Feathers eventually cover the crop area and personality begins to emerge.
Once the chick has grown enough to be able to fly, it generally leaves the nest. This is called fledging and the fledged bird is called a 'fledgling'. This occurs as early as 4 1/2 weeks in some individuals. Cockatiels experience a "pre-fledging shut-off period" between the ages of 4-5 weeks. This is a normal occurrence and is essentially a slimming down process which precedes the act of fledging. During this time, the normal quantity of formula is refused and regurgitation may be observed. The number of feedings should be reduced until the regurgitation ceases. Once fledging is accomplished, normal food consumption usually returns until the weaning process begins.
Weaning: Cockatiel chicks will wean when they are developmentally ready and not before. Because of this, weaning can be a stressful time for both the chick and the handfeeder.
Offer soft foods like soaked pellets, egg foods, rice as well as fresh water and small seeds. As the chick begins to refuse feedings, eliminate the mid-day feeding, followed by the morning and finally the evening meal. This will happen gradually between the ages of 6 weeks and weaning (approx 8 weeks). Stress and changes in the diet may cause temporary weight loss, and weight monitoring is recommended during this stage of development.
Crops should be checked before the late night feeding and once food is felt in the crop, the weight charts will reveal if the chick is actually sustaining or gaining weight on its own. Once weight is maintained for 5 days without formula supplementation, the chick is weaned, which is approximately between 8 and 9 weeks in cockatiels. However, yeast buildup in the crop of excessive gram-negative bacteria often retards the weaning process and any individual refusing to wean should be checked by an Avian Veterinarian.
Socialization of Babies: The parent birds in my aviary, when allowed to raise their babies to maturity, teach them many things. How much of their behavior is inate and how much is learned still remains a mystery to me. If left with a parent, they do learn to perch, preen, play, eat on their own, related to other birds and, unfortunately, the fear humans. If they are parent-raised and weaned, they can be taught to accept humans, but usually on their terms, and fear can definitely be detected in the early stages of training. However, if they are pulled for hand-feeding, they learn to accept humans as "birds" and there is virtually no fear. In fact, hand-fed birds will many times assert themselves with their human if things don't go their way. Based upon this knowledge, it is clear to me that at least social relatonships are learned, and I suspect that a good deal of the rest is as well. When we handfeed, we become the parent and it is our responsibility to teach our babies the things they don't pick up on their own or from their clutch-mates, such as eating a proper diet, relating to us, playing with toys, and obedience. A well-socialized baby cockatiel is a happy one!