A Retrospective Analysis of Postmortem Salmonella Dublin Cases in Dairy Cattle in British Columbia

Table 1

Characteristics of S. Dublin status among postmortem dairy cases (n = 1,331) submitted to the Animal Health Centre, Ministry of Agriculture, British Columbia.

Category	Subcategory	Total (%)	Positive (%)	Negative (%)
		n = 1,331	n = 90	n = 1,241
Season	Fall	385 (29.0)	28 (31.1)	357 (29.0)
	Winter	357 (26.8)	26 (28.9)	331 (27.0)
	Spring	288 (21.6)	16 (17.8)	272 (22.0)
	Summer	301 (22.6)	20 (22.2)	281 (22.6)
Farm region	Fraser Valley	1,197 (89.9)	80 (88.9)	1,117 (90.0)
	Okanagan	84 (6.3)	6 (6.7)	78 (6.3)
	Vancouver Island	31 (2.3)	4 (4.4)	27 (2.2)
	Creston	3 (0.2)	0 (0)	3 (0.2)
	Bulkley Valley	16 (1.2)	0 (0)	16 (1.3)
Age	Fetus	445 (33.4)	17 (18.9)	428 (34.5)
	Neonates	269 (20.2)	19 (21.1)	250 (20.1)
	Calf	274 (20.6)	47 (52.2)	227 (18.3)
	Young Heifer	83 (6.2)	5 (5.5)	78 (6.3)
	Older Heifer/adult	260 (19.5)	2 (2.2)	258 (21.0)
Breed	Holstein	1,252 (94.1)	87 (97.0)	1,165 (94.0)
	Jersey	68 (5.1)	2 (2.2)	66 (5.3)
	Brown Swiss	7 (0.5)	1 (1.1)	6 (0.4)
	Ayrshire	4 (0.3)	0 (0)	4 (0.3)