Liver proteolytic activity in tannic acid-fed birds.
The influence of tannic acid in the rate of growth (BWG), feed intake, protein efficiency ratio, and liver proteolytic activities (cathepsin A and D) were measured in growing male chickens. These birds were fed ad libitum over a 15-d experiment on 20% protein standard diets containing heated soybean (control, C) as the main source of protein. Tannic acid (TA; 25 g/kg diet) was added to all diets, except the control. It has been found that in comparison to control-fed birds, TA-fed birds showed a significant reduction (P < 0.01) in BWG, protein efficiency ratio, and relative weight of liver, together with a significant increase (P < 0.01) in the activities of cathepsin A and D in liver. Addition of TA to the control diet had no significant effect on feed intake. The possible nature of these results is discussed.
Marzo
F
F
Laboratory of Animal Physiology and Nutrition, School of Agromomy, Universidad Pública de Navarra, Pamplona, Spain. marzo@unavarra.es
Urdaneta
E
E
Santidrián
S
S
D000818:Animals; D002268:Carboxypeptidases / Q000378:metabolism*; D043402:Cathepsin A; D002402:Cathepsin D / Q000378:metabolism*; D002645:Chickens / Q000254:growth & development / Q000378:metabolism*; D047348:Hydrolyzable Tannins / Q000008:administration & dosage*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology; D008297:Male; D011897:Random Allocation; D015430:Weight Gain / Q000187:drug effects*
D047348:Hydrolyzable Tannins; D002268:Carboxypeptidases; D043402:Cathepsin A; D002402:Cathepsin D