Íslenskar landbúnaðarrannsóknir - 01.03.1977, Page 76

74 ÍSLENZKAR LANDBÚNAÐARRANNSÓKNIR
Table 1. Probabilities of fertilization and embryonic mortality.
Number and fate of fertilized eggs Probability
"Normal"sires:
Two eggs fertilized, both survive P
One egg fertilized, survives q
No egg fertilized (or "background" loss) i-p-q
Sum í
"Abnormal"sires:
Two eggs fertilized, both survive p(l-s)2
Two éggs fertilized, one survives 2p(1-s)s
Two eggs fertilized, none survives ps2
One egg fertilized, one survives q(l-s)
One egg fertilized, none survives qs
No egg fertilized (or "background" loss) 1 i
Sum i
Table 2. Probabilities of ewe falling into the T,S and R groups
(T-ewes with twins, S-ewes with singles, R-ewes returning on heat).
Sire group Ewe group Probability Observed numbers
"Normal" sires T P ni
S q n2
R r = 1-p-q n3
Sum 1 Ni
"Abnormal" sires T p(l-s)2 n 4
S 2ps(l-s) + q(l-s) n 5
R ps2 + qs + 1-p-q n6
Sum 1 n2