Page 82 - Hand rearing birds second

Incubation 65

27.0 Actual 13% 17%
Days weight
26.5 Actual weight (g) (g) Loss Loss
0 26.49 26.49 26.49
13% Loss
26.0 1 26.24 26.35 26.31
17% Loss 2 26.16 26.21 26.13
25.5 3 25.98 26.08 25.95
4 25.79 25.94 25.77
5 25.71 25.80 25.59
25.0 6 25.55 25.66 25.41
7 8 25.36 25.53 25.23
24.5
25.39
25.05
Weight (g) 24.0 10 9 25.05 25.25 24.87
25.26
25.11
24.97
24.69
24.51
11
24.78
24.97
12
23.5
24.15
13 24.57 24.84 24.33
24.70
24.48
23.0 14 24.30 24.56 23.97
15 24.21 24.42 23.79
16 24.02 24.29 23.61
22.5
17 23.81 24.15 23.43
18 23.69 24.01 23.25
22.0 19 23.56 23.87 23.07
20 23.38 23.74 22.89
21.5 21 23.22 23.60 22.71
22 23.07 23.46 22.53
21.0 23 22.92 23.32 22.35
12345678 9101112131415 16 17 18 19 20 21 22 23 24 25 26 24 22.78 23.18 22.17
25 23.05 21.99
Days of incubation
Figure­3.1­ Egg weight loss – Saint Vincent Amazon, Amazona guildingii, egg 2017 (Source: data courtesy of
Houston Zoo). Because frequent, small adjustments to humidity were initiated early in incubation, the
weight loss trend was kept on track which resulted in a successful self-hatch.
If the date the egg was laid or incubation started is unknown and cannot be estimated, it is more
difficult to manage weight loss. Such eggs should be set with parameters used successfully for the
same or similar species and the progression of the air cell closely tracked. Understanding when the
size of the air cell is appropriate for the stage of development can help determine whether the egg
weight loss trend is normal. If there are records for eggs of very similar size, the expected daily
weight loss for the current egg(s) can be estimated.
Ideally, eggs should be weighed daily and at the same time each day. This is particularly impor-
tant during the early part of incubation as it becomes increasingly difficult to change an estab-
lished weight loss trend later in incubation. When incubating very large numbers of eggs, weight
loss can be recorded and managed for the average of all eggs or for a representative subset.
­ Record­Keeping
Consistent, detailed record keeping is essential to successful hatching of eggs, analyses of results,
and ongoing refinement of techniques of artificial incubation. The following basic data should be
collected on each egg and/or clutch:
species;
●
individual egg identification number;
●
dam’s and sire’s identification, age, and reproductive history;
●
history of individual egg or clutch;
●
lay date;
●
set date (the date either natural or artificial incubation commenced);
●
expected term;
●