BASELINE HEMATOLOGY AND BLOOD CHEMISTRY OF STRIPED CATFISH, Pangasius hypophthalmus.  

Hematological and blood chemistry parameters are paramount diagnostic tools for understanding the health dynamics of animals and humans. Due to the advances in human and veterinary medicine, well-established reference ranges exist for a number of selected species. Yet, studies exploring the values of these blood components in fish, for research or food purposes, are scant. Meanwhile, bacterial diseases are a major concern of aquaculture-important species, inflicting substantial economic losses. Availability of information regarding baseline blood parameters in fish could play a crucial role in early detection of disease, facilitating control measures for disease, and decreasing animal losses, time and labor. Striped catfish, Pangasius hypophthalmus, is a commercially important species in Asia, and currently exported to the U.S., but there is no reported information about an initial baseline of its blood parameters. The objective of this work is to establish baseline values for the hematological and blood chemistry, which could contribute in understanding the overall health functions of this catfish species.

The study first focused on determining the blood chemistry parameters on striped catfish. Seventy catfish (range 50-200g) were grown in a 1600L recirculating aquaculture system for the work. On week 0, all fish were individually captured and anesthetized in 100mg/L MS-222 (tricaine methanesulfonate), and a non-lethal blood collection was achieved via puncture of the caudal vessels. A small sample of blood was transferred to capillary tubes, centrifuged, and then read in hematocrit-capillary tube reader for determining packed cell volume in blood. Plasma was separated from the remaining heparinized blood by centrifugation and then submitted for clinical chemistry analysis to the Veterinary Teaching Hospital at Virginia Tech.

At week 2, blood was collected non-lethally from the same fish for hematology analysis. The standard Wright-Giemsa, and Natt & Herrick staining methods were used for leukocyte differential, and total blood cell counts, respectively. All results from this study will constitute the first blood parameter profile for this important catfish species.