THE EFFECTS OF PROTEIN CONTENTS ON HYDROXIPROLINE CONTENT AND PHYSICAL QUALITY OF RABBIT SKIN

Abstract

Collagen is a major structural protein in skin and bones of all animals. Collagen
has an important effect on physical strength of skin as well as influences penetration of chemical use on leather tanning. Hydroxiproline is an amino acid present only in
collagenous protein; therefore, it can increase skin quality and improve leather tanning process. The research was conducted to evaluate the effect of different protein contents in rabbit feed that were 13 % (Pl), 16 % (P2) and 19 % (P3). The feed rations consist of concentrate BR-1, BR-2, water spinach (lpomoea sp), and cassava. All treatments were isoenergy that was 274O,8 cal. Drinking water was given ad libitum. The treatment was given to all rabbits for three months. After that, the animals were slaughtered and their skins were removed and sun-dried. Samples for hydroxiproline and physical quality test were taken from croupon area. The research used Completely Randomized Designs (CRD) and the differences among treatments were tested by Duncan’s Multiple Range Test. The results showed that the hydroxiproline content and physical quality of rabbit skins differed significantly ( P<0,0l) among treatments. The hydroxiproline content in skins of rabbits given feed containing 19 % protein was higher than that containing 16 % and 13 %. The values ofhydroxiproline were 11,8 % (19 % CP), 11,5 % (16 % Cl’) and 9,8 % (13 % CP). The tensile strength and elongation differed significantly (P<0,01). The values of tensile strength were 219,85 kg/cmz (19 % CP), 158,97 kg/cmz (16 % CP) and 152,27 kg/cmz respectively. The values of the elongation were 23,47 % (19 % CP), 21,33 % (16 % CP) and 20,10 % (13 % CP) respectively.