Mapping quantitative trait loci (QTL) in sheep. IV. Analysis of lactation persistency and extended lactation traits in sheep

Table 2 Phenotypic correlations among lactation persistency and extended lactation traits

Trait	Extended lactation						Lactation persistency
	MY	PY	FY	UY	LY	SCY	MY	PY	FY	UY	LY
Extended lactation protein	-0.18
Extended lactation fat	-0.25	0.67
Extended lactation useful yield	-0.12	0.72	0.69
Extended lactation lactose	-0.06	0.01	0.13	0.08
Extended lactation somatic cell	-0.04	0.62	0.64	0.83	0.08
Milk persistency	0.88	-0.20	-0.28	-0.12	-0.07	-0.02
Protein persistency	0.18	0.54	0.45	0.54	0.27	0.59	0.23
Fat persistency	0.21	0.18	0.28	0.31	0.21	0.31	0.25	0.64
Useful yield persistency	0.02	0.29	0.42	0.45	0.44	0.39	0.01	0.55	0.51
Lactose persistency	0.04	0.01	0.11	0.10	0.85	0.09	0.01	0.39	0.36	0.54
Somatic cell persistency	0.15	0.44	0.46	0.62	0.16	0.78	0.23	0.77	0.59	0.49	0.30

Correlations are shown for lactation persistency and extended lactation of milk (MY), protein (PY), fat (FY), lactose (LY), useful yield (UY) and somatic cell score (SCY) yields. Phenotypic correlations greater than 0.22 are highly significant (P ≤ 0.01), greater than 0.17 are significant (P ≤ 0.05), and smaller than 0.15 are not significant (P ≥ 0.1).

ISSN: 1297-9686