Estimation of genetic and phenotypic parameters in a closed ...

lf)
Standard error of the genetíc correlation (S.n.ra) was calculated
according to the method described by Robertson (1959) and is
as follows:
S.E.r^
LJ
-
r- (rr,-, ) 2 s.E.-2, . s.E 2
- '"'h (x) " '"_!{Ð
T h-h
xy
r'¡here :
S.E.r^(J
t'=
-c(>çv)
= standard error of genetic correlation
xandy
coefficient
genetic correlation coefficient between traits
S.E.-?--. = standard error of heritability
h (x)
of traÍt x
S.E."-2r--. = standard error of heritabílity
h (Y)
of trait y
h2
= heritability estimate of trait x
2
h--
v
heritability
estimate of trait y
II. Carcass measurements and age
to market weight
The analysis of variance and covariance described by Becker
(L967) was also used for estimation of genetic parameters in carcass
measurements and age to market weíght.
wÍthin years and farrowing groups in a
The analysis was carried out
nested classifÍcation with un-
equal numbers of progeny per sire and per dam. The procedures for
calculating heritabilities, phenotypic and genetic correlations were
as follows: