Comparison of methods for deriving phenotypes from incomplete observation data with an application to age at puberty in dairy cattle

Table 1 Population descriptive statistics of dairy heifers enrolled in age at first blood plasma progesterone elevation phenotype analysis

Breed^a	No. of animals	No. of herds	Average No. of heifers	No. of sires	No. sires with > 5 daughters
All	4,745	54	88	260	103
HF	2,307	54	43	166	66
J	24	1	24	7	2
XB	2,364	53	45	220	66
OTHER	50	19	3	35	0

^aBreeds are defined as: > 90% Holstein–Friesian (HF); > 90% Jersey (J); HF + J > 90% but HF < 90% and J < 90% (XB); and HF + J < 90% (OTHER)

ISSN: 2049-1891