Lukefahr S D, Cheeke P R, Patton N M
Int. Small Livest. Res. Center, Dept. Food Sci. & Anim. Ind., Alabama A&M Univ., Normal 35762.
J Anim Sci. 1990 Aug;68(8):2222-34. doi: 10.2527/1990.6882222x.
Market data on 1,315 rabbits from 201 litters from Californian (CAL), New Zealand White (NZW), CAL X NZW and NZW X CAL dams bred to CAL, NZW and Flemish Giant sires were subjected to multiple regression and path analyses. Market traits observed in litters at 56 d included average kit weight (A56W), litter size (LS56), total litter weight (L56W) and within-litter uniformity in individual weights (LCV). Preweaning variables as covariates included in the model were dam metabolic body weight (DMW), litter born (LSB), litter birth weight (LBW), milk yield from 1 to 21 d (MY) and feed intake from 1 to 28 d of the dam and litter (FI). Results from multiple regression analyses indicated linear and quadratic effects (P less than .20) due to LSB and MY for all four market characters. The LBW influenced (P less than .05) LS56 and L56W, and FI affected (P less than .05) LS56, L56W and LCV. Separate analyses were conducted involving 28-d weaning and feed intake variables as covariates: litter size weaned (LSW), litter weaning weight (LWW) and litter feed intake from 28 to 56 d (LFI). The three weaning covariates were important (P less than .05) for all market traits except LS56 (LWW was not significant). The most accurate regression equations were obtained from the weaning model for prediction of L56W and LS56 (R2 = .68 and .78). Path analyses revealed that preweaning covariates generally had direct rather than indirect effects on market traits. Both direct and indirect effects of weaning covariates were important for market traits. Results suggest that litter market traits of size and weight can be predicted with a reasonable degree of accuracy.
对来自201窝的1315只兔子的市场数据进行了多元回归和通径分析，这些兔子的母本为加利福尼亚兔（CAL）、新西兰白兔（NZW）、CAL×NZW和NZW×CAL，父本为CAL、NZW和弗拉芒巨兔。在56日龄时观察到的窝内市场性状包括平均仔兔体重（A56W）、窝仔数（LS56）、窝总重（L56W）和窝内个体体重的均匀度（LCV）。模型中作为协变量的断奶前变量包括母本代谢体重（DMW）、产仔数（LSB）、窝出生体重（LBW）、1至21日龄的产奶量（MY）以及母本和窝在1至28日龄的采食量（FI）。多元回归分析结果表明，对于所有四个市场性状，LSB和MY存在线性和二次效应（P小于0.20）。LBW对LS56和L56W有影响（P小于0.05），FI对LS56、L56W和LCV有影响（P小于0.05）。进行了单独分析，将28日龄断奶和采食量变量作为协变量：断奶窝仔数（LSW）、断奶窝重（LWW）和28至56日龄的窝采食量（LFI）。除LS56外（LWW不显著），这三个断奶协变量对所有市场性状都很重要（P小于0.05）。从断奶模型中获得了预测L56W和LS56的最准确回归方程（R2 = 0.68和0.78）。通径分析表明断奶前协变量通常对市场性状有直接而非间接影响。断奶协变量的直接和间接效应对于市场性状都很重要。结果表明，窝的大小和重量等市场性状可以得到合理准确的预测。
