Morphological Characterization of Two Light Italian Turkey Breeds

SIMPLE SUMMARY: Genetic resources on turkeys are scarce, considering both domestic and wild birds. Smaller, dark-colored Italian heritage breeds such as Brianzolo and Nero d’Italia have been selected for centuries in outskirt areas due to their coping ability in poor environments and high brooding ability. However, they are in danger of extinction. EC Council Regulations on organic farming strongly recommend using local genetic resources and conserving biodiversity. Phenotypical characterization is a basic step in biodiversity conservation; therefore, in this article, we present morphometric and colorimetric analysis results of 46 birds belonging to each of the considered breeds. We considered 18 parameters: morphometries, morphological indexes, linear evaluation, and colorimetric indexes as characterizing factors in breeds differentiation. Differences in weight with clear sexual dimorphism were recorded. Massiveness indexes were in favor of the slightly more compact Brianzolo breed. The extremely fair skin and dark shank of the Nero d’Italia turkey were revealed by colorimetric analysis. The effectiveness of morphological analysis in breeds differentiation, useful data in heritage breeds conservation, and characterization were considered control parameters in classifying animal products. ABSTRACT: We aimed to investigate the variability within turkeys’ phenotypical traits in two Italian heritage breeds: Brianzolo (BRZ) and Nero d’Italia (NIT), as analyzed through morphometry, morphometrical indexes, linear scoring, and colorimetric indexes. A total of 92 birds were measured, weighed, and scored (46 NIT: M/F = 19/27; 46 BRZ: M/F = 19/27). Live weight (LW), total body length (BL, excluding feathers), keel length (KL), chest circumference (BC), wingspan (WS), shank length (SL), shank diameter (SD), and shank circumference (SC). Massiveness (MASS), stockiness (STOCK), and long-leggedness (LLEG) indexes were also calculated. The body condition score (BCS) applied a linear evaluation to nutritional status and muscular development. Colorimetric indexes (L*, a*, b*) were recorded, sampling skin and shank. Data were analyzed using GLM procedures and PCA. NIT was the heaviest breed (4.89 vs. 4.07 kg; p ≤ 0.05). In both breeds, sexual dimorphism was visible in the LW trait with males (M) weighing significantly heavier than females (F) (p ≤ 0.05). NIT birds recorded the highest BL values: 58.44 vs. 57.15 cm (p ≤ 0.05). MASS was higher in NIT (8.26 vs. 7.0; p ≤ 0.05), and STOCK was higher in BRZ (82.62 vs. 85.37; p ≤ 0.05). Colorimetric indexes revealed significant differences in skin lightness (L*) and redness (a*). For shank color, the breed significantly affected differences in the indexes. This study characterizes these breeds at high risk of genetic erosion and extinction, which will help the morphological standardization of birds and the enhancement of genetic variability