. 2019 Feb 17;97(4):1456–1467. doi: 10.1093/jas/skz024

Table 2.

Reproductive parameters in beef heifers consuming either novel endophyte (EN) or endophyte-infected (EI) fescue with slick hair mutation (S) or wildtype (W) from late May to late August 2015

	Treatment¹ ²					P-value
Item	EN-S	EN-W	EI-S	EI-W	SEM	Fescue	Genotype	Interaction
Follicle number³
Preselected follicles⁴	12.18^a	10.60^b	11.07^a ^b	13.77^c	0.48	0.034^*	0.257	<0.0001^*
Selected follicles⁵	3.09	3.30	3.05	2.96	0.13	0.146	0.663	0.273
Preovulatory follicles⁶	0.94^a	0.88^a	0.85^a	0.52^b	0.04	<0.0001^*	<0.0001^*	0.002^*
Ovarian structure sizes
Ovulatory follicle, mm	9.88^a ^b	11.57^a	10.25^a ^b	9.14^b	0.69	0.150	0.674	0.053^†
Luteal area, mm²	297.2^a	272.7^a	276.8^a	235.1^b	11.7	0.015^*	0.005^*	0.467
Reproductive hormones
Estradiol, pg/mL	6.57^a	4.97^b	7.78^a	4.58^b	1.82	0.447	0.0001^*	0.191
Progesterone, ng/mL	2.38^a ^b	3.01^a	1.97^a ^b	1.53^b	0.46	0.035^*	0.837	0.243
Prolactin, ng/mL	140.9^a ^b	186.3^a	124.9^b	137.2^a ^b	31.2	0.050^*	0.057^†	0.873
PSPB⁷, ng/mL	3.36	3.05	3.13	N/A	0.28	0.515	0.430	0.848

Within row, means without a common superscript significantly differ (P ≤ 0.05).

Values are reported as least square means for the experiment.

EN-S = novel endophyte fescue with slick hair coat; EN-W = novel endophyte fescue with wildtype hair coat; EI-S = endophyte-infected fescue and slick hair coat; EI-W = endophyte-infected fescue with wildtype hair coat.

Follicle number is defined as a follicle observed during ovary mapping via transrectal ultrasonography.

⁴

Follicles were classified based on size: preselected follicles 2 to 4 mm, selected follicles 5 to 8 mm, and preovulatory follicles ≥9 mm.

⁵

Follicles were classified based on size: preselected follicles 2 to 4 mm, selected follicles 5 to 8 mm, and preovulatory follicles ≥9 mm.

⁶

Follicles were classified based on size: preselected follicles 2 to 4 mm, selected follicles 5 to 8 mm, and preovulatory follicles ≥9 mm.

⁷

PSPB = pregnancy-specific protein B.

P-values < 0.05 determined significant.

^†

P-values 0.05 > P ≤ 0.10 determined a statistical tendency.