Ovarian follicular response to oestrous synchronisation and induction of ovulation in Norwegian Red cattle

Table 1 Least square means (LSM ± SE) of the size of dominant follicles at ovulation following oestrous synchronisation

Variable	Class	n	Size, LSM ± SE
Herd	1	9	13.2 ± 1.5^a
	2	10	19.6 ± 1.6^b
	3	6	14.8 ± 1.5
	4	19	15.8 ± 1.2
Age	Heifers 14‒15 months	10	15.9 ± 1.0
	Heifers 16‒18 months	13	17.1 ± 1.0
	Heifers 19‒28 months	11	13.4 ± 1.5
	Cows parity 1‒3	10	16.9 ± 1.6
Initial follicle size^c	≤ 10.0 mm	21	15.4 ± 0.7
Initial follicle size^c	> 10.0 mm	23	16.3 ± 0.8
BCS	Lean (2.5‒2.9)	6	15.5 ± 1.7
	Moderate (3.0‒3.4)	20	15.2 ± 0.9
	Fat (3.5‒4.0)	18	16.9 ± 0.8

Number of animals (n) and least square means (LSM) ± standard error (SE) for size of the dominant follicle (diameter, mm) at ovulation by herd, and classes of age, initial follicle size¹, and body condition score (BCS)
^a,bLSM within variable and column with different superscripts differ; P < 0.05
^cDiameter of the dominant follicle at the time of GnRH analogue treatment (T0)

ISSN: 1751-0147