海狸色獭兔21日龄窝重(泌乳力)校正公式的制订与应用

The formulation and application of the correction formula for litter weight(lactation ability)at the age of 20 days in beaver-colored rex rabbit

[目的]21日龄窝重(泌乳力)是反映母兔繁殖性能的重要指标,但实际生产中,该指标通常不能被准确测定。本研究旨在通过对50窝海狸色獭兔18~23日龄窝重数据进行拟合分析,制订出泌乳力的校正公式。[方法]通过一次方程和二次方程分别对窝重数据进行拟合,比较两模型的拟合度(R^(2))和AIC值,确定最优模型。采用R语言中的plot函数绘制模型的回归诊断图,采用21日龄测定的真实窝重数据与模型拟合值进行比较,计算拟合度R^(2)。以21日龄为基准,推导出校正公式并计算出18~23日龄窝重的校正系数(C)。在此基础上计算泌乳力的校正值,并与测定值比较,计算出不同日龄的拟合度(R_(d)^(2))和总拟合度(R^(2))。[结果]通过对数据的拟合分析和比较得出最优的拟合方程为:窝重(y)=-1352.08+75.14×日龄(x_(1))+286.14×带仔数(x_(2)),拟合度R^(2)=0.4767。进一步推导出海狸色獭兔21日龄窝重的校正方程为:y_(校正)=y_(实际)+y_(实际)×(73.6×(实际日龄-21))/(65.3+319×带仔数),并计算出不同测定日龄和带仔数下的校正系数(C)。通过将21日龄校正值与测定值进行比较,得到校正方程的总拟合度为0.68。[结论]本研究通过对海狸色獭兔18~23日龄窝重数据进行分析得出泌乳力的校正公式,具有较高的拟合度,可在生产中推广。

[Objective]The 21-day-old litter weight(lactation ability)is an important indicator to reflect the reproductive performance of female rabbits.However,in actual productive practice,this indicator is usually difficult to be accurately measured.The purpose of this study was to formulate a correction formula for lactation by fitting and analyzing the litter weight data of 50 litters of beaver-colored rex rabbits aged 18-23 days.[Methods]The litter weight data were fitted by a linear equation and a quadratic equation,and the fitting degrees(R^(2))and AIC values of two models were compared to determine the optimal model.The plot function in R language was used to draw the regression diagnostic graphs of the model.The true litter weight data measured at 21 days of age were compared with the model fitting value,and the fit R^(2) was calculated.Based on the 20-day-old date,the correction formula was deduced and the correction coefficient(C)of the litter weight at the18-23-day-old was calculated.The corrected value of lactation ability were calculated using the formula as the basis,and compared with the measured values.The fitting degree(R_(d)^(2)) and total fitting degree(R_(2))of different age were calculated.[Results]The optimal equation was:Corrected litter weight(y)=−1352.08+75.14×age(x_(1))+286.14×litter size(x_(2)),with R^(2)=0.4767.Furthermore,the correction equation of 21 d litter weight was:y_corrected=y_real+y_real×(73.6×(age-21))/(65.3+319×litter size),and calculating C values under different with its overall fitting degree 0.68.[Conclusions]In this study,the 18-23 d litter weight data were analyzed and correction equation of 21 d was made with high fitting degree,which can be applied in rabbit production.