Sheep - AgRIS

Overnight teasing and drafting riddled ewes off in the morning. This is quite manageable
for small lots, but when large numbers have to be inseminated it takes lot of time as ewes
cannot be presented for A.I. at proper time during estrous. Under the circumstances the rams
have to be worked too frequently to provide necessary semen. When large number of ewes are
to be handled, harnessed vasectomised rams are released with the ewes at about 5 p.m. and the
mob turned into a paddock. They are mustered into the yards by 8.00 a.m. the following
morning and marked ewes drafted off. With few modifications to most sheep yards, this can be
done at the rate of 4,000 per hour.
Marked ewes are either insemianted to get the labour force acquainted with procedure and
a few rams checked and trained or these are put aside and brought back into the mob at the end
of the cycle. Generally the drafted ewes are insemianted on the acceptable type of estrous
mucus. Obviously those ewes which are drafted late in estrous are rejected.
9. 5.2.2 Insemination Procedures
Under the insemination technique there are a number of prerequisites such as equipment
for insemination, restraint of ewes, number of ewes for insemination and adjustment of
inseminations during better part of estrous period end whether heterospermic inseminations are
desirable or not.
i) Equipments
A speculum, a head light torch and a syringe with insemination pipette is all the equipment
required. There are three types of specula in use (1) the duck bill type, (2) metal barrel, and (3)
glass speculum. It is the usual experience that the duck bill type is easy for insertion and gives
greater ease and freedom of movement. It can be easily dilated in the vaginal passage and
removed in a closed condition afteruse. It is also easy for sterilization. A glass specdlum is also
used. A 2ml glass syringe attached to inseminating pipette with a rubber connection is most
convenient for insemination. A fresh insemination pipette should be used for each
insemination.
ii) Restraint of ewes for insemination
With the help oftwo attendants, ewes can be inseminated at the rate of 100 per hour, if the
operation is streamlined, using fresh neat semen. Various methods of holding ewes have been
used and some methods used in Australia between fifties and sixties are:
1. Ewes held upside down in a cradle.
2. Ewes placed on a battery of bails on a raised plateform.
3. Ewes held on a rail, as for lamb marking.
4. The operator working in a pit and a ewe manoeuvred upto a hock bar at the edge of it.
Other methods used in Asia and in South America, include the use of various cradle and
jacking devices to lift the hind quarters. These are not easy to operate. The method used in
Australia, at present, is for the attendant to saddle the ewe facing the tail and with a hand under
each flank to throw her hindquarters over a rail 24" above floor level. Attendant keeps the ewe's
hind legs extended by pressing into her stifles. If the ewe's front feet are on the floor, she will
not struggle. After insemination the ewe is released through a gate in the pen.
A false floor about 2 feet high is put into the catching pen to enable the inseminator to have
the ewes presented at eye level.
When the ewe is placed over the rail, an assistant inserts glass speculum whilst the
inseminator loads his syringe. The inseminator then holds the speculum, locates and positions
the cervical opening and inseminates the ewe. The semen is deposited in the cervix.
A simple wooden crate with sloping platform is considered for restraint. The rear portion is
raised to a height of 3 feet so that the inseminator can conveniently inseminate,in standing
position.
9. 6 Handling and management of Sheep Products
9.6.1 Wool
Skirting is done after shearing. It is removing the objectionable parts such as tags, leg
pieces, neck pieces, bellies, locks and stained portions from the body of the fleece.
After skirting the actual grading of the wool is done by a trained classer. The method of
classing in the principal wool-producing countries differs considerably. The grading or classing
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