SELECTED ARTICLES
ARTIFICIAL INSEMINATION IN CATTLE,
A Brief Review of the Technique *
SUMMARY OF CONTENTS
1. Possible applications of the practice in Great
Britain.
2. The Artificial
Vagina:
description of the
apparatus.
3. The technique of semen collection.
4. The examination of semen.
5. Technique of insemination.
6. Storage and transport of semen.
7. Note on the viability of spermatozoa in storage.
8. Dilution of semen.
9. Notes on cleaning of apparatus.
10. Apparatus and instrument required.
ADDENDUM.
Technique of making sperm counts
ARTIFICIAL insemination comprises the intro-
duction of spermatozoa into the female repro-
ductive tract by means of instruments, so that
direct contact between male and female
animals for breeding is unnecessary.
The modern method was first developed in
Russia, where it is now practised extensively in
horse, cattle and sheep breeding. It has also
been used with success in most European
countries, and in the U.S.A., the British Colo-
nies and elsewhere.
1.
POSSIBLE APPLICATIONS OF THE PRACTICE IN
CATTLE BREEDING IN GREAT BRITIAN
In this country artificial insemination has
been practised only on a very limited scale.
Nevertheless it has several possible applica-
tions, which can be summarized under two
headings—(a) Livestock Improvement; (b)
Disease Control and
Increased
Breeding
Efficiency.
(a) Livestock Improvement. It is generally
acknowledged that the milk yield of the
national herd could be considerably increased
by the more widespread use of first-class bulls.
The number of such bulls, particularly proven
ones, capable of transmitting increased milking
characters to their daughters is, however,
limited. By the employment of artificial
insemination it would be possible to increase
considerably the services of such bulls. With
proper organisation their services could be made
available to a wide circle of dairy farmers who,
chiefly for economic reasons, are at present
denied such advantages.
(b) Disease control and increased breeding
efficiency. Certain
diseases of the genital
organs are transmitted by coitus, e.g., Tricho-
moniasis, infectious vaginitis, and, possibly,
contagious abortion and certain forms of
metritis. This hazard applies within a herd but
is greater where communal or inter-herd bulls
are operating. Artificial insemination would
eliminate the risk of spread of genital diseases
by the bull, provided that the animal itself did
not harbour any infectious disease which could
be transmitted through coitus. In the case of
bulls used by co-operative breeding societies,
stringent veterinary examination would be
necessary to minimize the risk of transmission
of genital disease.
Trichomoniasis is a condition which might be
cited as an indication for artificial insemination
as a measure of disease control. When the
disease is well established in a herd, it is certain
that the bull will harbour the infection and
probably transmit it to clean animals during
coitus. In the bull treatment is usually un-
successful. To resume breeding in the herd
without delay it will be necessary to introduce
a clean bull, but if he is allowed to serve
naturally there is a grave risk that he also will
acquire the disease, for it is difficult to ascertain
with certainty when a cow which has once been
infected is free from the disease.
The adoption of artificial insemination will
ensure that the clean bull is protected from
infection and thus the continued dissemination
of the disease will cease.
Artificial insemination may also be utilized to
overcome difficulties in successful breeding
caused by some deformities and abnormalities in
the genital tract of the cow, which prevent the
normal passage of spermatozoa.
The artificial collection of semen provides a
means whereby a specimen suitable for micros-
copical and other forms of examination can be
obtained, and thus a check on the fertility of
the animal can be kept. This cannot be done
with such accuracy where natural service is in
use.
2. THE ARTIFICIAL VAGINA (A.V.): DESCRIP-
---- OF THE APPARATUS
Various methods of collecting semen have
been used, but it is now generally accepted
that the most satisfactory is the artificial
vagina. By adopting it, the whole ejaculate
* Reproduced from the N. V. M. A. Publications
No. 11, Artificial Insemination of Cattle, published by
The National Veterinary Medical Association of Great
Britain and Ireland.
246