Table 2. Prevalence and age distribution of Cryptosporidium in pigs in Heilongjiang Province, China by microscopy and by PCR.

Age (week)	By microscopy		By PCR
	No. of examined	No. of positive (%)	No. of examined	No. of positive (%)
<5	81	0	16	4 (25.0)
5–8	216	6 (2.8)	43	36 (83.7)
>8	271	3 (1.1)	54	23 (42.6)
Total	568	9 (1.6)	113	63 (55.6)