Subject: does the catalase enzyme work at a lower optimal temperature in fish ?

I am planning an investigation on the activity of catalase in relation to 
temperature, on the liver of a lamb (warm blooded animal)and cod liver
(cold blooded animal). I have already done some preliminary experiments 
with the lamb liver, which have proven my hypothesis.However working with 
small cod liver has been difficult, therefore I fear that my results are 
hindered. Is there anybody who may have carried out a similar experiment, 
if not, does anybody know anything on the physiology of cod liver? - if 
so, please help me. Thank you - From a very grateful A-Level student. 

Re: does the catalase enzyme work at a lower optimal temperature in fish ?