A report on the UK Dairy
Industry
Sex and the Single Cow
Fig. 9. Most dairy cows are impregnated by artificial
insemination, a stressful procedure which can cause serious injury if
performed improperly
Reproduction is at the heart of the dairy industry as cows must give birth
to calves in order to produce milk, and no other aspect of the cow’s
life is artificially manipulated to such a great extent.
Artificial Insemination
Very few dairy cows in the UK mate naturally. The majority are impregnated
by artificial insemination (AI), which involves passing a catheter through
the cervix of the cow and depositing the semen in her uterus (33). This is
an uncomfortable, stressful experience for the cow which can result in injury
if carried out by an untrained or inexperienced person (3). Under the Artificial
Insemination of Cattle (Animal Health) (England and Wales) Regulations 1985,
the procedure does not have to be performed by a veterinarian
and may be carried out by any member of farm staff who has received ‘appropriate
training’ (34). According to DEFRA it is now ‘largely
carried out by non-veterinarians’ (34). AI training courses
take place on working farms, using live animals for practice (34). In January
2005, DEFRA proposed amendments to the law that would permit farm workers
to practice on ‘spent’ cows in slaughterhouses before they
are killed, a practice banned in 2002 because it caused the animals unnecessary
suffering and stress (34).
Fig. 10. Semen production is now big business. Here a
Holstein bull ejaculates into a collection tube
Artificial insemination is so widespread because it is cheaper to purchase
frozen sperm than to feed and look after a bull. It also allows the farmer
to choose from a variety of breeds to sire the calves. It is common practice
for farmers to use semen from dairy breeds such as Holstein/Friesian for
50% of their inseminations and semen from beef breeds such as Charolais
or Hereford for the other half (25). This ensures a regular replacement of ‘good
milkers’ for the herd as well as a number of dual purpose calves
who can be sold for beef production (25). However, male calves who have
been sired by a dairy breed are of little use on a dairy farm as they do
not produce milk. They are also of little use to a beef farmer as they
do not put on muscle in the same way that beef breeds do. Male pure breed
dairy calves are simply unwanted by-products of dairy production and up
to 200,000 are killed every year shortly after birth (36, 37, 64). The
fate of dairy calves is discussed further in Calves – Unwanted By-products.
Fig. 11. Recognising that male calves are useless to
a dairy farmer, the AI company Cogent offer Sexed Semen which claims
to provide 90% heifer calves
In 2000, the British AI company Cogent began selling Holstein semen which
was sorted to pre-determine the sex of the calf and help farmers avoid ‘having
large numbers of unwanted Holstein bull calves born every year’ (38).
This product, they claim, gives an average result of 90% female sperm and
10% male sperm, allowing farmers much greater control over the cow’s
reproduction (38). However, sexed semen is not currently widely used as
it is very expensive (37).
Embryo Transfer
The use of invasive embryo technologies is increasing steadily in Europe
(26). To ensure that high quality cows produce more offspring than is naturally
possible, embryos are removed from their reproductive systems and transferred
into ‘lower quality’ cows who serve as surrogate mothers (3).
Embryos can either be collected directly from the ‘donor’ cow
or can be produced in vitro (in a test tube) with ‘donor’ cow
eggs retrieved through ovum pick-up (26).
Embryo collection: High quality cows are injected with
hormones to increase ovulation and are then artificially inseminated in the
usual manner (33). The resulting embryos, which can number from seven to
12, are flushed from her uterus using a catheter type instrument (33). As
this procedure takes place a week after oestrus, the uterus is more difficult
to penetrate than during artificial insemination and can result in bleeding
and sometimes even uterine rupture (33). The procedure is so painful that
UK law requires the use of an epidural (35).
Ovum pick-up: Unfertilised eggs are collected from ‘donor’ cows
by a needle inserted through the wall of the vagina and into the ovary (35).
According to DEFRA:
“Repeated epidural injections are necessary for this procedure
and they can cause welfare problems for the animals, such as severe pain
in the tailhead and lower back” (35).
Despite these welfare concerns, 26,000 embryos were produced using ovum
pick-up in the EU in 2000 (26).
Surrogate cows receiving the embryos, whether direct from the ‘donor’ cow
or from in vitro fertilization, are given hormone injections to bring on
heat (33). A gun is then used to insert the embryo high into the uterus,
a procedure requiring great skill which can only be acquired with practice
(33). The use of an epidural is compulsory (35).
Ultrasound scanning
Over the past decade the use of per rectum ultrasound to detect
pregnancy has become common on British dairy farms (3). This involves inserting
a long probe (about the thickness of a finger) into the cow’s rectum
until it lies over her uterus (3). Careless insertion or removal of the probe
can damage the rectal tissue and internal organs, causing great pain (3).
Both the Royal College of Veterinary Surgeons (RCVS) and the government’s
Farm Animal Welfare Council (FAWC) have expressed concerns over non-veterinarians
performing the procedure (3). Despite these concerns DEFRA still permit non-veterinarians
to carry out per rectum ultrasound as long as they have received ‘appropriate
training’ (34).
Fig. 12. Cows who have suffered injuries during calving,
such as nerve paralysis, may have hobbles attached to their hind legs
to hold them in place so they can carry on milking (Photo: Viva!)
 Click
here for a video clip of a cow in hobbles
Calving
Concerns have also been raised by the FAWC and the Food Ethics Council (FEC)
over the use of embryos or semen from large cattle breeds in smaller recipient
cows who will have difficulty giving birth to them (3, 33). This mismatch
can result in severe injuries to the cow during calving, including internal
haemorrhage, nerve paralysis and pelvic fracture (33, 39). According to the
National Animal Disease Information Service (NADIS) calving difficulties
are the cause of 46% of ‘downer cows’ – when a cow is unable
to stand up – on British dairy farms (39).
‘Downed’ cows require immediate attention to prevent injuries
which may only be temporary from causing permanent damage (3). A cow may ‘go
down’ because of temporary nerve paralysis caused by calving difficulties
or simply fatigue from her gruelling workload, but if left recumbent for
several hours permanent damage can be caused to her legs (due to her 700kg
body cutting off the blood supply) (37). Several different types of lifting
gear are used to get ‘downed’ cows on their feet again (3, 39).
These include:
- a hoist which is clamped to the cow’s hip bones
- a lifting bag which inflates underneath the cow
- a net or harness which allows the cow to hang suspended (3).
Hobbles and shackles are also commonly attached to the hind legs of cows
who have suffered muscle or nerve damage during calving and would not be
able to stand unaided, as illustrated in Fig. 12 (3, 39).
If the farmer were to cull a cow who was injured during calving he would
lose the large quantity of milk which she was about to produce. Injured cows
are therefore often forced to carry on, even when in pain, for seven to eight
months until their milk yield drops and they are killed.
Fig. 13. Modern dairy cows have such hugely enlarged
udders that their calves often have difficulty finding and reaching the
teats (Photo reproduced with kind permission of Tetrapak)
Dairy cows impregnated with large continental beef breeds such as Belgian
Blue, Charolais or Limousin are sometimes unable to give birth naturally
and must undergo caesarean section (3, 29). In order to prevent the need
for this major surgery, farmers using large continental breeds to sire
calves may induce calving before the cow reaches full-term (3). The FAWC
have raised concerns that induction of pregnancy increases the risk of the
placenta being retained, leading to infection of the uterus and premature
infertility (3). They therefore recommend that it only be used in extreme
circumstances and never as a routine procedure (3). Despite this advice,
DEFRA – in their
Code of Recommendations for the Welfare of Livestock: Cattle – state ‘induction
does have a role to play in preventing oversized calves’ (34).
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