The Neuquén-Criollo goat is a significant genetic resource, adapted to the singular harsh environment of North Patagonia. Its present gene pool was built up from different breeds since the Spanish colonization being Angora the latest introduced. High phenotypic diversity and their geographical distribution suggest a subdivision of this goat population into four close sub-areas. As phenotypic characterization was carried out on 827 Criollo adult goats. Analyse were based on fourteen quantitative (morphostructural) and eight qualitative (morphological) variables. Correspondence analyses for qualitative and canonical discriminant analysis for quantitative traits were performed, using hair types as classification variable. Results were consistent in differentiating the four considered sub-areas. Neuquen Criollo breed could be characterized in two ecotypes: Short and Long hair goats, a mixed type area and a crossbred area fulfil the types distribution. Principal divergence factors would be isolation, natural and artificial selection, transhumance and exotic breeds introduction. ZusammenfassungTitel der Arbeit: Phänotypische Differenzierung bei Exterieurmerkmalen der lokalen Criollo Ziegenpopulation in Patagonien (Argentinien) Die Neuquen-Criollo Ziege ist eine bedeutende genetische Ressource, die angepasst ist an die harten Umweltbedingungen Nord-Patagoniens. Der aktuelle Genpool ist seit der spanischen Kolonisierung von verschiedenen Rassen gebildet worden, wobei die Angora-Rasse die letzte eingeführte Rasse war. Phänotypische Diversität und geographische Verteilung lassen eine Differenzierung der Population in vier angrenzenden Gebieten vermuten. Eine phänotypische Charakterisierung von 827 ausgewachsenen Criollo Ziegen wurde durchgeführt. Vierzehn quantitative (morphostrukturale) und acht qualitative (morphologische) Merkmale wurden analysiert. Deskriptive Statistik, Korrespondence-Analyse für qualitative und Diskriminant-Analyse, für quantitative Variable wurden mit dem "Deckhaartyp" als Klassen-Merkmal ausgeführt. Die Ergebnisse stimmen mit der vermuteten Differenzierung in vier Gebieten überein. Die Neuquen-Criollo Ziege konnte in zwei Ecotypen: kurz-und langhaarig, charakterisiert werden. Gebiete mit gemischten Typen und mit Angora gekreuzten Typen wurden identifiziert. Die wichtigsten Differenzierungsfaktoren sind Isolierung, natürliche und künstliche Selektion, Transhumanz und Einführung von exotischen Rassen.

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SummaryThe effect of human intervention on the structure of locally adapted breeds in America is analyzed using the case of a rural community in Patagonia (Argentina) and its goats. The Neuquen Criollo Goat is analyzed focusing on the artificial selection practiced by the local rural community and its effects on the current type's distribution. Goatherd preferences in the selection of replacements were studied by means of a survey (n= 242). The distribution of 634 females of various types was recorded and compared with selection criteria through multivariate techniques. Producers showed clear grounds for the selection of their animals, size, conformation, hair type and coat color being the criteria most frequently cited. Most producers (84%) used at least two criteria to choose their replacements. Differences of criteria and phenotypes between areas were significant, as was the correlation between Chi-squared distances matrix on both data sets (r=0.78), showing the influence of human intervention on the breed's shape. Directional selection, practiced by rural communities in marginal areas, was the main factor of microevolution in this Criollo goat population, and probably in other Criollo populations in America.