The yeast hansenula anomala as a protein source for rainbow trout ( salmo gairdneri). hematological aspects

Abstract

1. 1. The effects of feeding rainbow trout ( Salmo gairdneri) with the yeast Hansenula anomala, grown on synthetic ethanol. as the only protein source, and some haematological parameters were studied. 2. 2. Haemoglobin content decreased and haematocrit value increased, although not significantly, but there was a significant increase ( P < 0.001) of the red blood cell count when trout were fed yeast diet. 3. 3. As a result of food treatment there was a very significant decrease ( P < 0.001) in the mean corpuscle volume (MCV) as well as in the mean corpuscle haemoglobin (MCH) and mean corpuscle haemoglobin concentration (MCHC). 4. 4. Blood smears showed different shapes of the erythrocytes (poikilocytosis) and the anisocytosis found correlated with the calculated MCV decrease. 5. 5. Serum proteins were not affected excepting β-globulin fraction, which significantly decreased ( P < 0.05) when expressed as g/100ml blood. Albumin: globulin ratio showed at the same time a significant increase ( P < 0.02). 6. 6. The possible role of iron transfer mechanism disorders on the appearance of a microcytic and hypochromic anemia is also discussed.