TABLE 2.

Typing BVDV from whole blood samples by multiplex PCR

Sample, origin,a anticoagulantc	Clinical status of donor animalb	Virus titer (TCID50/ml)	PCR (typing result)
			With RNA extraction	Without RNA extraction
B1, Ohio	C	≥1 × 104	2	2
B2, Ohio	C	≥5 × 102	1	1
B3, Ohio	C	NDd	1	1
B4, Ohio	C	≥1 × 104	1	1
B5, Ohio	C	≥1 × 104	1	1
105, Ontario	C	≥3 × 104	1	1
106, Ontario	C	≥6 × 104	1	1
108, Ontario	C	≥2 × 104	1	1
109, Ontario	C	≥1 × 105	1	1
8, Iowae	C	≥4 × 104	1	1
262, Iowa	C	≥4 × 103	2	2
794, Iowa, C	C	3 × 104	1	1
854, Iowa, C	C	2 × 104	2	2
859, Iowa, C	C	1 × 104	2	2
358, Manitobae	PC	≥3 × 104	1	1
625, Manitoba	PC	≥1 × 104	1	1
287, Manitoba, H	PC	1 × 104	1	1f
291, Manitoba, H	PC	1 × 105	1	1f
292, Manitoba, H	PC	3 × 104	1	1f
296, Manitoba, H	PC	1 × 105	1	1f
875, Manitoba, H	PC	1 × 105	1	1fg
1086, Manitoba, C	PC	6 × 104	1	1f
E1-515p, C	EI	2 × 104	2	2f
E2-515p, C	EI	1 × 102	2	2f
E3-515p, C	EI	1 × 102	2	2f
E4-515u, C	EI	4 × 103	2	2
E5-p11Q, C	EI	5 × 101	2	2f

^aBlood tested was previously frozen unless stated otherwise (see footnote f). Origin, location of donating laboratory. 

^bC, carrier; PC, probable carrier; EI, experimentally infected with BVDV2 (blood collected on day 6 or 7 postinfection). 

^cH, heparinized; C, citrated; otherwise not recorded. 

^dND, not determined. This sample was negative at a 1/100 dilution in an immunoperoxidase assay but was positive in an antigen capture enzyme-linked immunosorbent assay. It was obtained from animal BJ, which had previously been shown to have very low serum titers (7). 

^eBVDV in all Iowa and Manitoba samples was previously typed by PCR-based methods with identical results as above (4a). 

^fSamples were tested fresh without previous freezing. 

^gProduced a type 1 product only after freeze-thawing.