Blood parameters in brook trout Salvelinus fontinalis (Mitchill, 1815), affected by columnaris disease

Abstract

Mass death of farmed brook trout Salvelinus fontinalis reared in raceway culture on a commercial ¢sh farm was recorded in May. The condition was caused by natural infection with external signs of Flavobacterium columnare. Haematological analyses were carried out from peripheral blood from 10 ¢sh from each group. Anaemia was characterized by a reduced erythrocyte count and lower haemoglobin levels; the values of mean corpuscular volume and mean corpuscular haemoglobin were higher and the values of mean corpuscular haemoglobin concentration were decreased. Clinical chemistry analyses in blood plasma indicated decreased levels of total protein, glucose and total calcium and an increase in the urea level. Among the four enzymes analysed, a catalytic activity reaching multiples of the normal level was found in alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase. The catalytic concentration of alkaline phosphatase was decreased. Electrophoretic analyses of the plasma protein indicated a reduced level of albumin. The moribund ¢sh had a higher hepatosomatic index and their condition coe⁄cient after Fulton and after Clark was also higher.

Gross pathology, blood chemistry, lipid and peroxide contents in rainbow trout ( Oncorhynchus mykiss Walbaum) affected by experimental Arcobacter cryaerophilus infection at low water temperature

“…A fall shown in this study in the mean serum calcium concentration of the infected rainbow trout group is consistent with previous findings reported in fish infected with Aeromonas hydrophila (Harikrishnan et al, 2003), Flavobacterium columnare (Řehulka and Minařík, 2007), Aeromomas sobria and Aeromomas caviae (Řehulka, 2002). Reduction of the calcium concentrations in fish serum indicates a rise of cell stability, which seems to be normal for the sufficient oxygen uptake during the stressful period associated with infection.…”

“…The fall of blood glucose may be a signal of liver and muscle damage. Decreased glucose values were described in rainbow trout infected with Aeromonas and Streptococcus (Barham et al, 1980), brook trout infected with Flavobacterium columnare (Řehulka and Minařík, 2007), rainbow trout naturally and experimentally infected with A. cryaerophilus (Aydin et al, 2000) and both albino crosses and normal pigmented rainbow trout infected with A. cryaerophilus (Bulut and Aydin, 2004) similar to the results obtained in this study.…”

“…Decreased activity of ALP could be due to inhibition of enzyme, and fall in ALP activity may be taken as a sign of anaemia and an index of parenchymal damage in liver. A reduced ALP value in the blood serum has been observed in coho salmon with vibriosis (Harbell et al, 1979), in Atlantic salmon with coldwater vibriosis (Waagbø et al, 1988) and in brook trout with columnaris disease (Řehulka and Minařík, 2007). In this study, the decreases of serum AST and ALP activities in the experimentally infected fish might be attributed to dysfunction of the liver.…”

“…Total protein is used to evaluate protein metabolism (Aydin et al, 2000), and it is a significant indicator of homeostasis (Řehulka and Minařík, 2007). Decreased total serum protein has been reported with A. cryaerophilus infections (Aydin et al, 2000;Bulut and Aydin, 2004;Yildiz and Aydin, 2006), yersiniosis (Altun and Diler, 1999), Serratia liquefaciens infection (Aydin et al, 2001), motile Aeromonas septicaemia (Harikrishnan et al, 2003), streptococcosis (Chen et al, 2004), natural Aeromonas sobria and Aeromonas caviae infections (Řehulka, 2002), and nephritic syndrome (Chen et al, 2002).…”

The influence of physicochemical properties of water on plasma indices in brook trout (Salvelinus fontinalis, Mitchill) reared under conditions of intensive aquaculture

“…Fish blood plasma chemistry is a promising area in fish biology and clinical pathology although it requires further research particularly in assessment of normal range. More studies need to be performed with a focus on the clinical analysis of blood as an indicator of the physiological state of the brook trout in aquaculture (Diouf et al 2000;Řehulka and Minařík 2007). Moreover, apart from the inevitable differences in, e.g.…”