Oxford Democrat. [volume] (Paris, Me.) 1833-1933, 1920-08-31
AMONG THE FARMERS.
Animal fiusbandrv Invs.t,v,,,o,.
"sPEED TEE PLow."

Animal husbandry Investigations
As was pointed out some weeks a9t
10 this series the Maine Agriculture
experiment Station devised q uuantita
tive method of indicating the amount O.
inbresding. This is based upon the rela
Eon between the possible number ol
ancestors In any generation and the
actual number in the individual case
Ii assumes that there is no Relationship
unless it be known fact. This co.
ethcient expressed numerically may have
any value between 0 and 100. When
there is no breeding of relatives, that ia
no iubreediug, its value for each genera.
ton is o. As the intensity of inbreedinp
increases the coeficient increases. In
the first generation of brother and sister
breeding the coeffioisnt is so, in the
second generation of continued brother
and sister breeding the coefficient is Is,
the third generation S7.5 and thus ap-
prosches with each continued genera.
tiOn of brother and sister breeding the
maximum Of 100.
From the analysis of American Jersey
Cattle Club records Ii was found to the
ninth generation that the coeficient for
random samples of Jersey sires lay be-
tween 43 and So; register of merit bulls
between 81 and Is; random samples of
Jersey COWS between Al and 6S; and
register of merit cows between 80 and 81.
So that American Jersey cattle at the
present time may be said to be on the
average half as intensely inbred when
account is taken to the ninth ancestral
generation as would be the case u con-
tinued brother and sister breeding had
been followed. But IL this inbreedipg
be plotted the resultant curve is very
different from the curve of brother and
sister inbreeding.
In general, register of merit animals
are less intensely inbred than the gen.
eral population Of Jersey animals.
Bulletin PSI OF the Maine Station gives
an analysis of the transmitting qualities
OF Jersey sires for milk yield, buttsr-fat
percentage and yield of butter-fat. In
this bulletin sires Of superior merit are
defined as those which raise the milk
and butter-fat production of their daugh.
,ers as compared with that of their
dams. The inferior sires are defined as
those which lower the milk and butter
fat production of their daughters as
compared with their dams. The analy-
sis of the pedigrees for the relationship
between sire and dam of the individual
bulls in the two groups shows that
there is little or no difference in this
respect. The group of sires poorer in
their transmitting qualities are more in
bred than the group of sires with supe-
rior transmitting qualities.
In general, though not true in each
individual case, Jersey animals of the
highest production In milk and butter
fat percentage are not Is much inbred
as those OF lower production.
In general, though not true in each
individual case, Jersey sires who are
able to increase the milk and butter
fat production Of their offspring are less
inbred than those that cannot.
But inbreeding Is not the sole measure
by any means. In fact until the answer
being sought by the Maine Experiment
Station in its cross breeding experiment
on inheritance Of milk and butter.fst is
found, no rule or rules for selection of
sire will be likely to hold true.-Chss.
D. Woods, Director.