Table 1.

Structure of the somatic cell score (SCS) datasets of the Holstein cows lactation-wise¹

Item	Dataset	LSCS1	LSCS2	LSCS3	LSCS4	LSCS5
No. of records	1	146,738	153,680	89,135	46,299	20,976
	2	77,065	80,601	81,954	41,770	19,165
No. of sires	1	797	822	804	744	655
	2	672	683	685	653	583
No. of dams	1	112,524	116,671	71,538	38,861	18,253
	2	63253	65,653	66,503	35,579	16,935
No. of herds	1	3,818	3,831	3,748	3,431	2,833
	2	3,126	3,130	3,130	3,037	2,619
No. of contemporary groups (herd-year)	1	25,886	27,728	23,064	17,278	10,874
	2	18,917	20,235	21,213	15,603	9,958
Average age (mo)	1	25.85	40.02	53.22	66.00	78.65
	2	25.56	39.21	53.18	66.03	78.66

LSCS, lactation averages of SCS

¹LSCS_{1 to 5} are consecutive lactation average somatic cell scores for 1st to 5th lactations.