Íslenskar landbúnaðarrannsóknir - 01.03.1977, Page 35

EWE PRODUCTION TRAITS 33
Table T. Mean and standard deviation (within flock) for the
number of lambs and ewe body weight. s
Trait X
Number of lambs born 1,63 0,46
Number of lambs weaned 1,5 7 0,47
Body weight in October 56,83 5,40
Body weight in January 56,91 5,23
from the analysis of variance and covariance Dickerson (1959) modified by Becker
within and between sires of ewes within (1967), and the sampling error of the genetic
flocks. The sampling error of heritability correlation with the formula of Robertson
estimates is calculated by the formula of (1959).
•Table 2 . Analysis of variance. Number of lambs per ewe at birth.
Source of variation All ewes Ewes with recorded body weight
D.F. M.S. D.F. M.S.
Total, within f lock 37463 0,216 18469 0,219
Total reduction 7 31,514 13 17,995
Age of the ewe 7 3.1,5143™ 7
Regression, date of mating 1 11,370XX
Regression, date of mating,
squared 1 11,128
Regression, body weight in Oct. 1 0,021
Regression, body weight in Oct.,
squared 1 0,014
Regression, body weight iri. Jan. 1 16,365xx
Regression, body weight in Jan., w
squared 1 10,472
Residual 37456 0,210 18456 0,206
R2 0, 0272 0,0579