Traits during hatching period
% fertility = number of egg fertilenumber of egg set X 100
% heritability= number og egg hatchednumber of fertile egg set X 100
EXAMPLE:
2000 eggs
93 infertile eggs
1728 chicks hatched
Solution:
% fertility = 2000-932000 X 100 = 19072000 x 100 = 95.35%
% heritability = 17281907 X 100 = 90.6% * Therefore, the percentage of fertility and percentage of heritability for chicks during hatching period is 95.35% and 90.6% respectively.
Traits during laying
Hen house egg production per bird = number of egg laidnumber of hen housed
% hen-house egg production = number of egg laid x 100number of hen-housed x number of days
% hen-day egg production = = number of egg laid x 100number of hen days
EXAMPLE:
On Oct, 1, 1990, 1223 pullets were laying in pens fitted trap nest. Individual hen daily egg production was recorded on the trap nest sheet up to Feb, 28, 1991. The date of dead and culling during that period was recorded. Calculate hen-day egg production percentage and hen-house production percentage.
Month (days) | No. of hen | Total hen days | No. of eggs laid | Oct | 1223 | 37627 | 20001 | Nov | 1203 | 35955 | 25684 | Dec | 1189 | 36699 | 26661 | Jan | 1180 | 36334 | 24280 | Feb | 1165 | 29398 | 20337 | Total | 5960 | 176013 | 116863 |
% hen-day egg production = number of egg laid x 100number of hen days = 116863 x 100176013 =66.39%
% hen-house egg production = number of egg laid x 100number of hen-housed x number of days = 116863x 1001223 x 151 =