Impact Factor is a population statistic that reflects how many citations of a journalâs papers published over a two-year period receive during the subsequent year. âThe annual Journal Citation Reports impact factor is a ratio between citations and recent citable items published: a journalâs impact factor is calculated by dividing the number of current year citations to the source items published in that journal during the previous two years.
The utilisation of nutrients depends on the presence and quantity of appropriate digestive enzymes. There are several enzymes involved in the digestion of feed into subunits appropriate for absorption in the Gastrointestinal (GI) tract of fish, and there are variations in enzyme activity between species. In terms of enzyme activity in different regions of the GI tract of Eurasian perch, the activity of carbohydrases and lipase was unaffected by growth rate and age (P>0.05). However, significant differences were found in the enzyme activity between different tissues. No effect of age or size on enzyme activity in Eurasian perch was observed in the present study.The relatively high activity of some digestive enzymes in the liver of both Eurasian perch and Arctic charr was unexpected. This may be due to an infiltration of endocrine or exocrine pancreatic tissue into the liver or due to intracellular liver enzymes.In conclusion, the high lipase and protease activity and low carbohydrase activity in both species can be linked to their carnivorous feeding habits. Total carbohydrase activity was higher in Eurasian perch than in Arctic charr, which had a higher total chymotrypsin activity and lipase activity in the mid-intestine. The data presented suggests that feed formulation should be different for Eurasian perch and Arctic charr in order to match their inherent digestive enzyme activities. This applies in particular to the carbohydrate content and composition of the feed. Based on the recorded Î±-amylase and carbohydrase activities, the carbohydrate content, in particular starch, can be higher in feed for Eurasian perch than in feed for Arctic charr.(Langeland M, Lindberg JE, Lundh T,Digestive Enzyme Activity in Eurasian Perch (PercaFluviatilis) and Arctic Charr (SalvelinusAlpinus))
Last date updated on July, 2014