A NONLINEAR MODIFICATION OF WOODS EQUATION FITTED TO LACTATION CURVES OF SARDINIAN DAIRY EWES

被引：46

作者：

CAPPIOBORLINO, A ^{[1
]}

PULINA, G ^{[1
]}

ROSSI, G ^{[1
]}

机构：

[1] UNIV SASSARI,FAC AGR,IST ZOOTECN,I-07100 SASSARI,ITALY

来源：

SMALL RUMINANT RESEARCH | 1995年 / 18卷 / 01期

关键词：

LACTATION CURVES; DAIRY EWES; NONLINEAR EQUATION;

D O I：

10.1016/0921-4488(95)00713-U

中图分类号：

S8 [畜牧、动物医学、狩猎、蚕、蜂];

学科分类号：

0905 ;

摘要：

Wood's equation, which is a widely used mathematical model for lactation curves, is not sufficiently flexible in situations frequently found in dairy sheep. For this reason a modified non-linear (y = at(bexp(-ct))) version was tested on the individual production (expressed in grams) of 64 Sardinian dairy ewes with differing production levels, type of lambing and udder health. The results showed that the modified version of the model (a = 702.3 +/- 56.2, b = 1.29 +/- 0.09, c = 0.133 +/- 0.013) fits the lactation curves well (R(2) = 0.905; residual standard deviation 145.3) with few interactions required for convergence (<5). Production level and type of lambing influenced all parameters, whereas udder health influenced only the a parameter.

引用

页码：75 / 79

页数：5

共 24 条

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