The microsporidian Enterocytozoon hepatopenaei is not the cause of white feces syndrome in whiteleg shrimp Penaeus (Litopenaeus) vannamei

Table 3 PCR and in situ hybridization results for microsporidia in a second set of shrimp ponds

Normal shrimp	Pond 3 CV5 (n=10)		In situ	Pond 7 YOT4 (n =5)		In situ
sample number	1^stPCR	2^ndPCR	Hyb	1^stPCR	2^ndPCR	Hyb
1	-	+	-	-	-	-
2	-	-	+	-	-	-
3	-	+	+	-	-	ND
4	+	+	++	-	-	ND
5	-	-	-	-	-	ND
6	-	+	-
7	-	+	+
8	-	-	+
9	-	+	+
10	-	+	+
Summary	Infected 9/10			Infected 0/5
WFS shrimp	Pond 13 BAP (n=10)		*In situ*	Pond 6 YOT (n=10)		*In situ*
sample number	1 ^st PCR	2 ^nd PCR	Hyb	1 ^st PCR	2 ^nd PCR	Hyb
1*	+	+	+	+	+	++
2	-	+	-	+	+	++
3*	-	-	-	+	+	ND
4	-	-	-	-	+	++
5	-	-	-	+	+	++
6	-	-	ND	+	+	ND
7*	-	-	ND	-	+	++
8*	-	-	ND	+	+	ND
9	-	+	-	-	-	ND
10	-	+	-	-	-	ND
Summary	Infected 4/10			Infected 8/10

* Histology of shrimp in these ponds showed no signs of microsporidian infection but 4 showed signs of severe bacterial infections of the HP that may have masked any microsporidians present. The remaining 6 samples looked normal with no signs of microsporidian infection.
Detection of microsporidia by PCR and in situ hybridization in 2 normal and 2 WFS ponds. Hyb ++ indicates extensive positive in situ hybridization reactions in HP tissue while Hyb + indicates light focal positive reactions and Hyb – indicates no reaction. ND Not done.

ISSN: 1746-6148