Table 3.

Proportion of herds with selected parameters in good (≥ 85%) and low (< 85%) farrowing rate (FR) categories from a herd evaluation completed on 30 commercial swine farms in Ontario

		Good FR herds		Low FR herds
Evaluation step	Parameter	Percent positive	N	Percent positive	N	Pb
Herd survey	Feed tested for mycotoxins	100.0	6	61.9	21	0.14
	Gestating sows fed 2×/day	50.0	6	16.7	24	0.12
	Weaned sows fed 2×/day	66.7	6	25.0	24	0.18
	Weaned sows fed gestation ration	0.0	6	41.7	24	0.14
	Weaned sows fed lactation ration	66.7	6	29.2	24	0.16
	Swollen vulva used as sign to detect estrus	83.3	6	34.8	23	0.06
	Vaginal mucus used as sign to detect estrus	16.7	6	52.2	23	0.18
	Hormonesa used to induce estrus in weaned sows	100.0	6	60.9	23	0.14
	Erysipelas present in herd	33.3	6	70.8	24	0.16
	PRRSv vaccine used in breeding herd	100.0	6	62.5	24	0.14
Breeding observation	Hands-free AI used	0.0	5	60.0	20	0.04
	Vulvas wiped before breeding	20.0	5	75.0	20	0.04
Semen evaluation	Poor quality fresh semen	0.0	5	38.8	18	0.15
	Poor quality stored semen	40.0	5	55.5	18	0.64

^aPregnant mare serum gonadotrophin and human chorionic gonadotrophin (P.G. 600; Intervet Canada, Whitby, Ontario).

^bFisher’s exact test used to determine statistical differences.