Mortality outbreaks in whiteleg shrimp (Penaeus vannamei Boone 1931) cultured in Peninsular Malaysia

Kua B. C., . and Mohd Fariduddin O., . and Marzukhi O., . and Ahmad Iftikhar A. M., . Mortality outbreaks in whiteleg shrimp (Penaeus vannamei Boone 1931) cultured in Peninsular Malaysia. pp. 242-256. ISSN 0116-6514

The whiteleg shrimp (Penaeus vannamei Boone 1931) was introduced for farming in Malaysia in early 2002. In 2009 reports of early mortality syndrome (EMS) were noted in the People's Republic of China and Viet Nam. One form of EMS acute hepatopancreatic necrosis disease (AHPND) has now spread to several shrimp-growing countries in Asia. In 2011 Malaysia recorded a mortality outbreak that prompted an investigation of 20 farms where 204 moribund shrimp samples were analyzed. On average 64 of the affected shrimp showed haemolymph clotting time longer than 1.5 min and 80 had pale hepatopancreas soft body and empty gut. Multiple bacterial infections particularly Vibrio spp. and Photobacterium damsela were isolated from the haemolymph and hepatopancreas of affected shrimp. Vibrio parahaemolyticus was detected positive for the toxR gene. Histopathology showed massive sloughing of the epithelial cells of the hepatopancreatic tubules and multifocal septic and melanized hepatopancreatic tubules that were encapsulated by haemocytes. Tests by polymerase chain reaction (PCR) were negative for infectious myonecrosis virus (IMNV) (0/110) and only a low prevalence (7/196) of infectious hypodermal and haematopoietic necrosis virus (IHHNV) was recorded. Infected shrimp also tested positive for paralytic shellfish poison (PSP) (24/24) and rearing water samples showed ammonium nitrate sulfide and iron levels above the optimal range for culture purposes. In 2012 samples were detected positive for EMS/AHPND using the IQ2000 Ems2 detection kit. The findings from this investigation showed that shrimp had multiple bacterial infections and pathological changes consistent with AHPND; some affected shrimp were positive for IHHNV and PSP toxin. These findings support the conclusion that mortalities were due to EMS/AHPND.

Full text available from: Official URL: http://www.asianfisheriessociety.org/publication/d...

Abstract

The whiteleg shrimp (Penaeus vannamei Boone 1931) was introduced for farming in Malaysia in early 2002. In 2009 reports of early mortality syndrome (EMS) were noted in the People's Republic of China and Viet Nam. One form of EMS acute hepatopancreatic necrosis disease (AHPND) has now spread to several shrimp-growing countries in Asia. In 2011 Malaysia recorded a mortality outbreak that prompted an investigation of 20 farms where 204 moribund shrimp samples were analyzed. On average 64 of the affected shrimp showed haemolymph clotting time longer than 1.5 min and 80 had pale hepatopancreas soft body and empty gut. Multiple bacterial infections particularly Vibrio spp. and Photobacterium damsela were isolated from the haemolymph and hepatopancreas of affected shrimp. Vibrio parahaemolyticus was detected positive for the toxR gene. Histopathology showed massive sloughing of the epithelial cells of the hepatopancreatic tubules and multifocal septic and melanized hepatopancreatic tubules that were encapsulated by haemocytes. Tests by polymerase chain reaction (PCR) were negative for infectious myonecrosis virus (IMNV) (0/110) and only a low prevalence (7/196) of infectious hypodermal and haematopoietic necrosis virus (IHHNV) was recorded. Infected shrimp also tested positive for paralytic shellfish poison (PSP) (24/24) and rearing water samples showed ammonium nitrate sulfide and iron levels above the optimal range for culture purposes. In 2012 samples were detected positive for EMS/AHPND using the IQ2000 Ems2 detection kit. The findings from this investigation showed that shrimp had multiple bacterial infections and pathological changes consistent with AHPND; some affected shrimp were positive for IHHNV and PSP toxin. These findings support the conclusion that mortalities were due to EMS/AHPND.

[error in script]

Item Type:	Article
AGROVOC Term:	Prawns and shrimps
AGROVOC Term:	Penaeus vannamei
AGROVOC Term:	Penaeus
AGROVOC Term:	Shellfish culture
AGROVOC Term:	Disease outbreak
AGROVOC Term:	Polymerase chain reaction
AGROVOC Term:	Bacterial diseases
AGROVOC Term:	Animal diseases
AGROVOC Term:	Vibrio
AGROVOC Term:	Vibrio parahaemolyticus
Depositing User:	Mr. AFANDI ABDUL MALEK
Last Modified:	24 Apr 2025 00:54
URI:	http://webagris.upm.edu.my/id/eprint/7987

Actions (login required)

View Item