The coat colour is an important evolutionary trait. In animals, the colouring of the body is crucial for mimicry, communication, sexual selection, and for regulating important physiological processes associated with the production of pigments. In the artificial selection of domestic animals, the tendency is to standardize coat colour and the colour pattern. On the contrary, the only Slovenian and critically endangered goat breed, Drežnica goat, varies severely in these traits. Therefore, it represents a unique genetic resource for studying the colour of hairs and patterns. The purpose of this B.Sc. thesis is to qualitatively and quantitatively determine the types of coat colour in relation to the presence of two main pigments, eumelanin and feomelanin, and to classify animals based on the colour pattern type in an analysis of 377 goats of Drežnica breed. According to the colour of the hairs, the largest group of animals (70%) expressed the dark pigment (eumelanin, mostly black), followed by the group with both, eumelanin and light pigment (feomelanin), were present (19%), in the least frequent group (11%) animals expressed mostly feomelanin. In the analysis of colour patterns, eight main groups were identified. Most of the animals were classified as with "no pattern" with predominantly black hairs colour (38.5%), followed by a »red cheek« group (16.4%), white or tan (11%), swiss markings (8.2%), peacock (5.3%), blackbelly (4%), grey (3%) and lightbelly (2.7%). Animals which could not be classified in any of the described standard colour pattern types were ranked in the ninth, the so-called combined-intermediate group (11%). We conclude that the diversity of coat colour and patterns in Drežnica goat is very high, especially in comparison with cosmopolitan breeds of goats such as Alpine or Saanen. This B.Sc. thesis is the first of a kind study and can serve as a reference for the characteristics of the coat colour and patterns in Drežnica goat further on, as well as a basis for further research of the colour variability and selection mechanisms and preservation of this breed in its original type.
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