Ferguson F A, Lukefahr S D, McNitt J I
Department of Animal & Wildlife Sciences, Texas A&M University-Kingsville 78363, USA.
J Anim Sci. 1997 Mar;75(3):611-21. doi: 10.2527/1997.753611x.
Influence of several preweaning variables on market trait determination was investigated using 338 fryer rabbits from 52 litters. Variables measured at 1, 8, and 15 d included litter size, individual kit body weight (BW), within-litter rank score for BW, and litter uniformity (coefficient of variation for BW among littermates; CV). Daily milk consumption in wk 1, 2, and 3 was used to determine average weekly dominance rank score and total weekly milk consumption. Market traits were individual average daily gain (ADG) and litter feed intake (FI) from 28 to 70 d, and 70-d BW (BW70), litter uniformity (CV70), litter size (LS70), and within-litter rank score for BW (RANK70). Market traits were analyzed separately by week involving preweaning variables and season of weaning as covariates. The week models provided the most accurate predictions of ADG, BW70, FI, and LS70 (R2 = .542, .712, .906, and .970, respectively). Prediction of CV70 and RANK70 was poor (R2 = .202 to .369). Season influenced ADG, BW70, and FI (partial R2 values of .285 to .435). Path analysis indicated that milk consumption and BW were more important in BW70 determination (28.4, 26.4, and 36.9% of total variation in wk 1, 2, and 3, respectively) than litter size (partial R2 < or = 2.0%). In wk 1, litter size plus dominance rank score primarily determined LS70 (direct and indirect contributions of 62.3 and 21.5%). Because of major seasonal influences, management should take measures to optimize feed intake and to improve doe milk yield and fryer gain performance.
利用来自52窝的338只肉兔幼崽，研究了断奶前的几个变量对上市性状测定的影响。在第1、8和15天测量的变量包括窝仔数、个体幼崽体重（BW）、窝内体重排名分数以及窝内均匀度（同窝幼崽体重的变异系数；CV）。第1、2和3周的每日牛奶摄入量用于确定每周平均优势等级分数和每周总牛奶摄入量。上市性状包括28至70日龄的个体平均日增重（ADG）和窝采食量（FI）、70日龄体重（BW70）、窝内均匀度（CV70）、窝仔数（LS70）以及窝内体重排名分数（RANK70）。将断奶前变量和断奶季节作为协变量，按周分别分析上市性状。周模型对ADG、BW70、FI和LS70的预测最为准确（R2分别为0.542、0.712、0.906和0.970）。对CV70和RANK70的预测较差（R2为0.202至0.369）。季节影响ADG、BW70和FI（偏R2值为0.285至0.435）。通径分析表明，在BW70的测定中，牛奶摄入量和体重比窝仔数更重要（第1、2和3周分别占总变异的28.4%、26.4%和36.9%）（偏R2≤2.0%）。在第1周，窝仔数加上优势等级分数主要决定了LS70（直接和间接贡献分别为62.3%和21.5%）。由于季节的主要影响，管理应采取措施优化采食量，提高母兔产奶量和肉兔增重性能。
