Haematology of Fish

This study is conducted to examine the impacts of different rearing temperature and diet variation on haematological and serum biochemical parameters on the juvenile Lutjanus malabaricus, a commercially important fish species in Malaysia. Fish (16-18 cm) were divided into eight treatments (4 temperatures × 2 diets) each with three replicates of five juveniles each. Fish were subjected to four different rearing temperatures (22, 26, 30 and 34°C) and fed with a commercial pellet and a natural shrimp diet. After 30 days of experimental period, blood samples were collected and transferred into two different tubes from each sample: One containing EDTA as an anticoagulant agent and the other without EDTA for serum collection. All the haematological and biochemical parameters in all the treatments were within the normal range. Changing temperature and diet led to a significant change (p<0.05) in the total length (TL), body weight (BW), red blood cell (RBC), haemoglobin (HB), haematocrit (HC), thrombocyte (TC) and white blood cell (WBC) but the change in mean corpuscular volume (MCV), mean cell haemoglobin (MCH) while mean cell haemoglobin concentration (MCHC) were not significant (p>0.05). The fish reared at 26°C and 30°C had significantly higher values than those reared at 22°C and 34°C (p<0.05). Total protein (TP), albumin (ALB), albumin/globin ration (A/G ratio), alkaline phosphatase (AP), aspartate aminotransferase (AST) and alanine transaminase (ALT) level were also significantly increased at 30°C and 26°C compared to that of 34°C and 22°C. Globulin (GLB) level showed the opposite trend. In all the cases the performances were higher in shrimp diet than pellet diet. It is suggested that these physiological parameters can be conveniently employed as health monitoring tools in fish culture practices. ABSTRAK Kajian ini dijalankan bagi meneliti impak perbezaan suhu dan variasi diet pada parameter hematologi dan serum biokimia pada juvenil Lutjanus malabaricus, satu spesies ikan komersial penting di Malaysia. Ikan (16-18 cm) dibahagikan kepada lapan rawatan (4 suhu × 2 diet) dan terdapat tiga replikat (5 ikan setiap replikat) bagi setiap rawatan. Ikan terdedah kepada empat suhu yang berbeza (22, 26, 30 dan 34°C) dan diberi makan pelet komersial dan diet udang semula jadi. Selepas 30 hari tempoh uji kaji, sampel darah diambil dan dipindahkan ke dalam dua tiub yang berbeza daripada setiap sampel: satu yang mengandungi EDTA sebagai agen antikoagulan dan yang lain tanpa EDTA untuk pengumpulan serum. Semua parameter hematologi dan biokimia dalam semua rawatan berada dalam julat normal. Perubahan suhu dan diet menyebabkan perubahan ketara (p <0.05) dalam jumlah panjang (TL), berat badan (BW), sel darah merah (RBC), hemoglobin (HB), hematokrit (HC), trombosit (TC) dan sel darah putih (WBC) tetapi perubahan jumlah min korpuskul (MCV), min sel hemoglobin (MCH), manakala nilai min kepekatan sel hemoglobin (MCHC) tidak signifikan (p > 0.05). Nilai yang lebih tinggi dilihat pada ikan yang diternak pada 26 dan 30°C daripada yang diternak pada 22 dan 34°C (p <0.05). Jumlah protein (TP), albumin (ALB), nisbah albumin/globin (nisbah A/G), alkali fosfatase (AP), tahap aspartat aminotransferase (AST) dan alanine transaminase (ALT) juga meningkat dengan ketara pada 30°C dan 26°C berbanding dengan 34°C dan 22°C. Tahap Globulin (GLB) menunjukkan keputusan yang bertentangan. Dalam semua kes, prestasi juvenil lebih tinggi apabila diternak menggunakan diet udang berbanding diet pelet. Parameter fisiologi yang digunakan dalam kajian ini telah dicadangkan sebagai pemantau kesihatan yang mudah dalam penternakan ikan.

A combination of biological monitoring (Biomonitoring) and measurements of water and sediment quality can provide a good indication of conditions and potential risks to any water body, which is an essential step in the development of efficient decision support tools for environmental managers. This study was carried out to investigate the possibility of using blood metal concentrations of two fish species Oreochromis niloticus niloticus and Clarias gariepinus as biomarkers of metal pollution, for the first time, to evaluate the health of the River Nile environment. Water, sediment and fish samples were collected seasonally from eighteen different sampling points, representing six different sites (three points from each site) along the whole course of the River Nile in Egypt. The present result concluded higher mean concentrations of nearly all the detected heavy metals in water and sediment samples collected from sampling sites downstream River Nile (polluted sites) compared to those collected from upstream river. The mean concentrations of all the detected metals were significantly (P<0.05) higher in the blood of fish collected from the polluted sites. Pb and Cd in blood serum collected from O. niloticus niloticus were significantly correlated (P<0.05) with corresponding levels in water and sediment samples collected from same sites. Likewise, Pb in blood serum collected from Clarias gariepinus was significantly correlated (P<0.05) with corresponding Pb in water and sediment samples collected from same sites, while Cr and Zn were significantly correlated only with sediment collected from same study sites. The results revealed species specific different sensitivities, suggesting that Nile tilapia may serve as a more sensitive test species compared to the African catfish. These results indicate that the blood metal concentrations of the selected species are adequate biomarkers of metal pollution and could be included in monitoring programmes to indicate the response of such animals to metal pollution.