Apparent Prevalence of Beef Carcasses Contaminated with Mycobacterium avium subsp. paratuberculosis Sampled from Danish Slaughter Cattle

Table 1

Number- and group-specific percentage (in brackets) of muscle tissue samples from slaughtered cattle from which Mycobacterium avium subsp. paratuberculosis DNA was detected by IS900 PCR at threshold cycle value of 36, 37, and 38 by age, type, of herd, breed type and fat code. Positive results were defined in relation to possible fecal contamination to the tissue samples.

Variable	Level		Including samples with fecal contamination				Excluding samples with fecal contamination
		Total no. in group	PCR threshold cycle value			Total no. in group	PCR threshold cycle value
			36	37	38		36	37	38
		501	20 (4)	28 (6)	42 (8)	385	16 (4)	22 (6)	34 (9)
Age	<2 years	197	16 (8)	21 (11)	31 (16)	159	3 (1)	4 (2)	8 (4)
	≥2 years	304	4 (1)	7 (2)	11 (4)	226	13 (8)	18 (11)	26 (16)
Herd type	Dairy	313	17 (5)	22 (7)	30 (10)	235	13 (6)	17 (7)	23 (10)
	Beef	115	2 (2)	3 (3)	7 (6)	88	2 (2)	3 (3)	7 (8)
	Veal	73	1 (0)	3 (4)	5 (7)	62	1 (2)	2 (3)	4 (6)
Breed group	Dairy	362	18 (5)	26 (7)	35 (10)	278	14 (5)	20 (7)	27 (10)
	Beef	76	1 (1)	1 (1)	4 (5)	62	1 (2)	1 (2)	4 (6)
	Cross	63	1 (2)	1 (2)	3 (5)	45	1 (2)	1 (2)	3 (7)
Fat code	1	66	1 (2)	3 (5)	8 (12)	56	1 (2)	3 (5)	7 (13)
	2	162	9 (6)	14 (9)	15 (9)	125	7 (6)	10 (8)	11 (9)
	≥3	272	10 (4)	11 (4)	19 (7)	203	8 (4)	9 (4)	16 (8)