Table 2. Proportion of dairy cows showing the normal and altered epidermal growth factor (EGF) profile and their EGF concentrations on day 3 in Hokkaido and Kyusyu regions.

Region	EGF profile	June–September		October–January		Total
		No. (%) of cows showing indicated profile	EGF concentrations (ng/g tissue weight)	No. (%) of cows showing indicated profile	EGF concentrations (ng/g tissue weight)	No. (%) of cows showing indicated profile	EGF concentrations (ng/g tissue weight)
Hokkaido	Normal	58 (64.4) a	6.71 ± 0.97	72 (83.7) b	6.71 ± 1.04	130 (73.9)	6.71 ± 0.99
	Altered	32 (35.6) a	1.66 ± 0.73	14 (16.3) b	1.42 ± 0.70	46 (26.1) A	1.59 ± 0.71
	Subtotal	90 (100)	4.92 ± 2.59 a	86 (100)	5.81 ± 1.83 b	176 (100)	5.37 ± 2.11
Kyushu	Normal	66 (54.5) a	7.01 ± 1.32	57 (83.8) b	6.76 ± 0.62	123 (65.1)	6.89 ± 0.44
	Altered	55 (45.5) a	1.12 ± 0.48	11 (16.2) b	1.68 ± 0.66	66 (34.9) B	1.21 ± 0.53
	Subtotal	121 (100)	4.33 ± 2.61 a	68 (100)	5.97 ± 2.34 b	189 (100)	5.01 ± 2.42
Total	Normal	124 (58.8) a	6.87 ± 1.12	129 (83.8) b	6.73 ± 0.92	253 (69.3)	6.80 ± 0.99
	Altered	87 (41.2) a	1.32 ± 0.68	25 (16.2) b	1.53 ± 0.68	112 (30.7)	1.37 ± 0.68
	Subtotal	211 (100)	4.58 ± 2.60 a	154 (100)	5.88 ± 2.06 b	365 (100)	5.13 ± 2.32

^{a, b} Values with different letters within the same row significantly differ (P < 0.05). ^{A, B} Values with different letters within the same column slightly differ (P = 0.07). The three-way ANOVA for seasons (June–September and October–January), regions (Hokkaido and Kyushu) and EGF profile (normal and altered) indicated only main effect of EGF profile on the endometrial EGF concentrations (P < 0.01). None of the interactions were significant. EGF concentrations are presented as means ± SDs. EGF profile was determined by the value of endometrial EGF concentration on Day 3; EGF concentration of between 4.7 and 13.5 ng/g tissue weight (normal range) was considered to be normal, whereas that of < 4.70 and 13.5 < ng/g tissue weight was considered to be altered based on previous findings [36, 38].