Department of Anatomy, Faculty of Veterinary Medicine, Siirt University, Siirt 56100, Türkiye.
Institute of Graduate Studies, Istanbul University-Cerrahpasa, Istanbul 34320, Türkiye.
Poult Sci. 2024 Sep;103(9):104008. doi: 10.1016/j.psj.2024.104008. Epub 2024 Jun 22.
The neurocranium in birds provides valuable insights into their morphological diversity, including adaptations related to brain size, facial shaping, and environmental factors. This study analyzes the neurocranial shape characteristics and size of chickens with similar genetic backgrounds. By examining the neurocranial shape variation in chickens of the same age and sex, the study aims to understand the factors contributing to morphological diversity within this specific group. 3D geometric morphometrics was used to analyze 235 neurocrania from four chicken breeds. The analysis revealed significant differences in centroid size among the chicken breeds. The largest neurocranium centroid size was found in Sasso chickens., which were statistically separated from Atak-S. Additionally, centroid size effectively differentiates between Lohmann Brown and Lohmann Sandy chicken breeds. The most significant shape variation concerned the width of the rostral part of the frontal bone. However, according to the PC1 value, the shape variation was observed within rather than between groups. Lohmann Sandy chickens exhibited higher variability in neurocranial shape, suggesting greater shape diversity within this breed than others. As for shape analysis, the breeds showed closer similarity to each other. Lohmann Sandy chickens are characterized by positive PC1 value, with the rostral end of the frontal region inclined more ventrally, and a more extensive basioccipital region. Sasso chickens have a more dome-shaped middle part of the frontal region than other breeds. The study also identified the most significant shape variation among the study samples, observed at the rostral part of the frontal bone. These findings contribute to understanding the genetic and environmental influences shaping neurocranial morphology in chickens. Similar studies in different bird species and subspecies offer valuable insights into avian biology and adaptation.
鸟类的颅神经提供了有价值的见解，了解其形态多样性，包括与大脑大小、面部形状和环境因素相关的适应。本研究分析了具有相似遗传背景的鸡的颅神经形状特征和大小。通过检查同龄和同性别鸡的颅神经形状变化，本研究旨在了解导致该特定群体形态多样性的因素。使用 3D 几何形态测量学分析了来自四个鸡品种的 235 个颅神经。分析表明，鸡品种之间的质心大小存在显著差异。最大的颅神经质心大小出现在 Sasso 鸡中，它们与 Atak-S 统计学上分离。此外，质心大小有效地区分了 Lohmann Brown 和 Lohmann Sandy 鸡品种。最显著的形状变化涉及额骨额部的宽度。然而，根据 PC1 值，形状变化是在组内而不是组间观察到的。Lohmann Sandy 鸡的颅神经形状变化具有更高的可变性，表明该品种的形状多样性高于其他品种。至于形状分析，各品种彼此之间更为相似。Lohmann Sandy 鸡的特征是 PC1 值为正，额区的前端更向腹侧倾斜，基枕骨区更广泛。Sasso 鸡的额区中部比其他品种更呈圆顶状。该研究还确定了研究样本中最显著的形状变化，发生在前额骨的前部。这些发现有助于了解塑造鸡颅神经形态的遗传和环境影响。在不同鸟类物种和亚种中进行类似的研究为鸟类生物学和适应提供了有价值的见解。
