Hematological responses of <i>Tilapia guineensis</i> to acute stress

Abstract

The effects of acute stress due to handling and transportation on the hematology of Tilapia guineensis was investigated. A total of sixty T. guineensis consisting of thirty juvenile fish (mean length 15.68m±322SD; mean weight 90.36g ±4.81SD) and thirty adult fish (mean length 22.74cm ± 4.78; mean weight 412.92g ± 6.23) were harvested from the recruitment ponds of the African Regional Aquaculture Centre, Brackish water Research Fish Farm, Buguma, Rivers State, Nigeria. Their blood samples were immediately taken at the site. They were then subjected to series of handling procedures like capture, sorting and transfer from the pond site to hatchery. The fish were later transported a live in an open circular plastic tank to Port Harcourt, over a distance of 40 km by road. Their blood samples were collected again after the transportation. The results obtained indicated a significant reduction (p<0.05) in mean values of Hemoglobin (Hb), Packed cell volume (PCV), Red blood cell, (RBC), Mean Corpuscular Hemoglobin Concentration (MCHC), Mean Corpuscular Hemoglobin (MCH) and Thrombocytes. The number of White Blood Cell (WBC), Mean Corpuscular Volume (MCV), Neutrophils, (Neut) Lymphocytes (Lymp), and Monocytes (Mon) increased. The variations in these blood parameters were more pronounced in adult fish than the juveniles. This study showed that the adult fish are more susceptible to stress than the juveniles.

Keywords: Hematology, stress, handling, transportation, Tilapia guineensis

International Journal of Natural and Applied Sciences, 5(4): 338-343, 2009