336 SWINE ENTERPRISE
ever hog cholera is likely to be prevalent all swine should be immunized
by the so-called double treatment. This consists in inoculating each animal
with enough virus to give the disease and at the same time inoculate him
with enough serum to control the disease. Such double treatment renders
pigs immune for life. It can be done about two weeks or so after weaning.
At this age the cost is slight. For full instructions see special swine books.
Dosage tables accompany the virus and serum.
All males not to be saved for breeding purposes should be
castrated rather early in the suckling period. Choose a day when
the weather is neither too hot nor extremely cold. Avoid infection
by flies and filth.
Weaning.—The time to wean depends upon several things:
(1) The season of the year. (2) The availability of skimmilk, pas-
tures, and other substitutes for the mother’s milk. (3) Whether
the owner plans to raise two litters a year from each sow. Six
weeks 1s young enough to begin weaning and seldom should the
pigs be left with their mother after eight or ten weeks from birth.
When a pig creep has been in use through the latter part of
the suckling period pigs will often wean themselves, and the mother
will cease the production of milk, without any definite effort to
wean the pigs. Indeed this plan makes the weaning period less
serious both to pigs and mother. Heavy milking sows must not
have their pigs removed all at once. The pigs may be allowed to
nurse once a day for a week or so. Another plan is to take away
the largest pigs and leave a few small ones with her longer.
Feeding After Weaning.—Both the sow and the litter should
have good pasturage after the weaning period. Give the pigs skim-
milk or make a slop of semisolid buttermilk and middlings. If
the pasture contains clover or other leguminous crops water may
be used in the mash instead of milk. Continue this ration giving
plenty of the wet mash twice a day for six weeks.
The sow, if kept on good pasturage with good water and a
supply of minerals, will need very little grain except corn. Avoid
‘eeding enough to make her very fat. Keep her in good physical
condition, ready for the next breeding period.
Culling Out Poor Sows.—The good observer will note great
differences between sows while they are raising their litters. Before
breeding for the next litter decide definitely which sows should be
removed from the herd and fattened for pork. Culling may be
done immediately after weaning the litters. Put the culled sows
on a fattening ration of corn with a little tankage or middlings.
Force them to fatten quickly as this plan is most economical.
Never keep sows over for breeding that produce small litters: