Page 560 - Hand rearing birds second

560 Hand-Rearing Birds

Nowhere is it more important to have good sanitation habits than in the area of food preparation.
Food is prepared indoors on stainless steel counters using separate cutting boards and knives for
fruit and meat items to minimize bacterial contamination. Keepers wash their hands regularly
during the preparations. All perishable food items are kept refrigerated and are not allowed to sit
out in the sun after being delivered. Live forage items – such as crickets, mealworms, anoles, and
mice – are housed for 3–4 days prior to being fed to chicks. The housing, food, and water containers
for these items are cleaned regularly. The sources where prey items are obtained are inspected to
ensure that the product is high quality.

Expected Weight Gain

Chicks are weighed daily prior to feeding until fledged and less frequently thereafter. Weights are
recorded and added to a growth curve to be compared with weights of previously reared normal
chicks (Figure 36.5a–d). Amounts of food fed are recorded, along with a rating of feeding response
and the presence of feces. Feed charts are computer spreadsheets with formulas to calculate
percent weight changes in chicks and to tally amounts fed of solids and fluids. On a daily basis,
keepers enter the chick weight; intake target, based on a percent of body weight; and frequency of
feedings, as prompted from a protocol. The target amount to be fed for the day and for each feeding
is automatically calculated on the spreadsheet. For instance, if a chick weighs 10 g, the desired
intake is 35% and the frequency of feedings is 7 times a day; then one multiplies 10 times 0.35 and
divides by 7 to determine that the chick will be fed 0.5 g per feeding. Comparisons are then easily
made between the goals for the day and what was actually ingested. Quantities of supplements
given are also calculated based on the amount fed the previous day.
Observations of growth and development milestones, such as eyes opening and fledging, are
documented during the rearing process (Figure 36.6). If chicks survive and have developed at the
same rate as parent‐reared chicks, one wants to use those same milestones as a measure for the
next chicks reared (Table 36.5).

Figure 36.6 Wrinkled Hornbill chicks at day 23 and 28. Source: photo © Zoological Society of San Diego.