The relationshi s among carcass weight, acid-base-balance of the blood as an indicator for metabolic load susceptibif&, meat quality parameters, and body Composition were investigated in rainbow trout. Examinations were carried out in two replicates using a total of 300 trout from a Danish population. Within replicates, the trout were of ap roximately the same age. In Replicate I trout, increasing carcass weight was accompanied by a more arkaline reaction of the blood. Carcass weight was significantly correlated with blood-pH and bicarbonate concentration (.19 and .26). Regression coefficients, however, confirmed only an increase of bicarbonate concentration with increasing carcass weight (b = .013 mmol/L per g, sb = 0.005). In meat quality parameters, muscular pH14 values decreased linearly in both replicates with increasing carcass weight, as shown b significant correlation estimates (-20 and -.27) and regression coefficients (b = -.0006, sb = .0002, a n d i = -.001, sb = .0003). Relationshi s of other meat quality parameters to inmeasin5 carcass wei ht were evaluated differently by corriation and regression coefficients. No relationship was found %etween carcass weight and body composition. In general, correlation estimates describing interrelations between acid-base and meat quality arameters were on a very low level. Independent from carcass weight, there were clearly metabolically!oaded and unloaded trout as well as trout with a mixed acid-base-status. Acid-base parameters were significantly correlated with each other. Generally, estimates for correlations between meat quality parameters were on a very low level. Body composition arameters, dry weight and crude fat content were highly significantly correlated (0.47) in Replicate h; in Replicate I there was no interrelation.