Acta Veterinaria et Zootechnica Sinica ›› 2025, Vol. 56 ›› Issue (9): 4341-4354.doi: 10.11843/j.issn.0366-6964.2025.09.018

• Animal Genetics and Breeding • Previous Articles     Next Articles

Methodological Theory of Linear Appraisal for Conformation Traits of Dairy Goats in China

MA Yannan1,2(), LI Zhengjie1, ZHANG Xiao3, GUO Beibei3, FANG Hua4, LIU Zijia4, CHEN Shiwei5, HE Pengjia4, WANG Xiaolong6, CHEN Yulin6,*(), LEI Zhaomin4,*()   

  1. 1. College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
    2. Institute of New Rural Development, Northwest Normal University, Lanzhou 730070, China
    3. Bureau of Animal Husbandry and Veterinary of the Huan County, Huan County 745700, China
    4. College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
    5. Weihe Dairy Group, Huan County 745700, China
    6. College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China
  • Received:2025-02-19 Online:2025-09-23 Published:2025-09-30
  • Contact: CHEN Yulin, LEI Zhaomin E-mail:mayannan@nwnu.edu.cn;chenyulin@nwafu.edu.cn;Leizm@gsau.edu.cn

Abstract:

This study aimed to construct a methodological framework for the 9-point linear type evaluation system of dairy goats and provide technical support for dairy goat breeding practices in China. The study based on the type evaluation systems of dairy goats in Europe and the United States. Scoring traits were selected according to their heritability (h2≥0.15) and economic importance. Using 36 720 phenotypic records from 1 530 Saanen dairy goats, the biological extreme range of scoring traits were determined through normal distribution analysis. A phenotypic-linear score-functional score conversion model was developed. According to China's production systems and breeding objectives, the weight allocation for body regions and scoring traits was quantified, the deduction rules for defective traits, and a scoring model with a standardized grading method, as well as the fundamental conditions for linear type evaluation of Chinese dairy goats were established and clarified, and the map of each scoring trait was drawn by Adobe Illustrator 2022 software. Twenty scoring traits, covering four body regions—udder system (42%), legs and feet (28%), dairy strength (20%), and rump (10%)—were selected, defined, and quantified with their respective weights, meanwhile, 20 defective traits and their corresponding deduction values were proposed. By determining the biological extreme ranges of the 20 scoring traits, a 9-point linear scoring system was established based on their normal distribution frequency, accompanied by 60 illustrative diagrams. This study will provide a scientific technical framework for the linear evaluation of conformation traits of Chinese dairy goats. It will also hold significant theoretical and practical importance for establishing a genetic evaluation system for dairy goats and promoting genetic improvement in the seed industry in China.

Key words: dairy goat, conformation traits, linear appraisal, methodological

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