PHENOGENETIC ANALYSIS OF PIGMENTATION OF A NEW COAT COLOR MUTATION OFAMERICAN MINK (MUSTELA-VISON SCHR L) AND ITS COMBINATIONS WITH SOME OF THE KNOWN MUTATIONS

A new dominant coat color mutation ''talitsa'' was revealed in the min k population of ''Znamenskii'' state fur farm (Tverskaya oblast', Russ ia). Qualitative analysis and quantitative assessment of the hair pigm ent of minks with the standard coat color, Talitsa, Royal-Pastel and A merican pearl mutations, as well as Talitsa X Royal-Pastel and Talitsa X American Pearl hybrids were conducted. It was shown that hair of al l genotypes studied contained only one pigment type, namely, eumelanin . Hair of the standard-colored minks showed the greatest eumelanin con tent, whereas hair of Talitsa X Royal-Pastel and Talitsa X American Pe arl hybrids showed the least content. The morphologic patterns of pigm entation of the mutant minks studied was described, including the shap es, dimensions and color of the pigment granules, as well as their dis tributions throughout the length and layers of the hair. Talitsa mutat ion was demonstrated to behave as a strong coloration attenuator in co mbinations with the Royal-Pastel and American Pearl mutations. It was proposed that the main mechanism determining the phenotypic expression of the Talitsa mutation is the reduction of number of melanocytes in the hair bulbs.