Table 1.

Summary of phenotypic data in terms of mean, standard deviation, minimum, maximum, coefficient of variance, and SNP-based heritability and standard error (SE) for each trait.

Trait	N	Mean	SD	Min	Max	C.V.	${\mathit{h}}_{\mathrm{SNP}}^2$	SE
LTN	100	7.36	0.48	7.00	8.00	6.55	0.29	0.21
RTN	100	7.42	0.61	6.00	9.00	8.17	0.19	0.21
TNUM	100	14.78	0.97	14.00	17.00	6.56	0.36	0.23
MAXAP	100	7.50	0.59	7.00	9.00	7.93	0.38	0.22
L-R	100	−0.06	0.51	−2.00	2.00	NA	0.00	0.20
ADIFF	100	0.22	0.46	0.00	2.00	NA	0.24	0.20

LTN: the number of teats on the left side; RTN: the number of teats on the right side; TNUM: the total number of teats (TNUM = LTN + RTN); MAXAP: the maximum number of teats in LTN and RTN (MAXAP); L-R: the difference between the two sides (L-R = LTN − RTN); ADIFF: the absolute difference between left and right teat number (ADIFF = |LTN − RTN|).