Table 3. Semen quality of three Japanese Black bulls.

Bull	Age (months)	Motility	Concentration (/ml)	DNA damage by TUNEL * (%)	IVF {%, (no. of embryos, r)}
JA	159.1	73 a	1.2 × 109	2.3 a*	22.8 a	(34/149, 3)
JB	75.3	45 b	1.0 × 109	6.9 b*	8.9 b	(24/284, 6)
JC	19.9	95	0.4 × 109	6.9	2.0 c	(4/177, 4)

No. of embryos: number of blastocyst-stage embryos for a certain number of oocytes cultured after in vitro fertilization. r: repeat number for IVF experiment. ^{a, b, c} The values with different superscripts within the same column are significantly different (P < 0.05). ^a*^{, b}* Takeda, et al., 2015 [13].