title: Influence of dietary protein level and the amino acids methionine and lysine on leather properties of blue fox (Alopex lagopus) pelts.
abstract: The influence of dietary protein, methionine, and lysine on leather quality in blue fox pelts was studied. The pelt material originated from animals in two consecutive feeding trials (Exp. 1 and Exp. 2) with three protein levels: conventional, slightly lowered, and very low. The two lowest protein diets were fed as such or as supplemented with methionine or with lysine (lysine only in Exp. 2). The following physical leather properties were measured: breaking load (BRL), tensile strength (TEN), relative elongation at break (PEB), straining of skins at pelting, and shrinkage at dressing. A decline in the dietary protein content reduced BRL and, hence, leather firmness, and increased straining and the corresponding shrinking in Exp. 1. The supplemented methionine tended to improve leather strength and elasticity by increasing TEN and PEB in Exp. 1, whereas lysine elicited no response. Methionine supplementation at the slightly lowered protein level increased BRL in both experiments by almost 10% as compared with the respective non-supplemented diet. We conclude that with high protein quality diets, a level of 200 g/kg DM (as digestible protein) appears to be adequate for producing pelts with firm, elastic leather, provided that an adequate amount of methionine is included in the diet.
authors.affiliation: University of Helsinki, Department of Animal Science, Helsinki, Finland. tuula.dahlman@stkl-fpf.fi
authors.forename: Tuula
authors.initials: T
authors.lastname: Dahlman
authors.forename: Marja
authors.initials: M
authors.lastname: Mäntysalo
authors.forename: Palle V
authors.initials: PV
authors.lastname: Rasmussen
authors.forename: L L
authors.initials: LL
authors.lastname: Skovløkke
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D004044:Dietary Proteins / Q000008:administration & dosage* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004548:Elasticity; D005589:Foxes / Q000378:metabolism / Q000502:physiology*; D006197:Hair; D008239:Lysine / Q000008:administration & dosage; D008715:Methionine / Q000008:administration & dosage; D011897:Random Allocation; D012867:Skin / Q000737:chemistry*; D012879:Skin Physiological Phenomena; D013718:Tensile Strength
chemical_list: D004044:Dietary Proteins; D008715:Methionine; D008239:Lysine