Cattle Breeding
BST [1]
BST is a version of the cow's own growth hormone which was produced from recombinant DNA transferred to E. coli and cloned. It is used to increase the yield of milk in dairy cattle by 10-20%. There are serious concerns about the effects of this growth hormone on dairy cows.
According to Monsanto, a company that produces Posilac (its own BST), BSTtreated cows are "at an increased risk for clinical mastitis" and that "the use of Posilac may result in an increase in digestive disorders such as ingestion, bloat and diarrhoea ... cows injected with Posilac have increased numbers of enlarged hocks and lesions of the knee ... and second lactation or older cows have more disorders of the foot region ... use has been associated with reductions in haemoglobin." BST is injected daily into the dairy cow and results in more nutrients from the animal's feed being directed to milk production. Thus encouraging the same quantity of milk being produced by fewer cows.
BST is currently given by daily injection and there will be discomfort for the cow associated with regular injections. Abcesses are liable to form on the injection sites. Professor John Webster points out, "enough is enough. The dairy cow is already busting her gut. We don't need it. The public doesn't want it. The cows don't need it".
Thankfully, the use and marketing of the genetically engineered milk-boosting hormone, Bovine Somatotrophin (BST) in dairy cattle has been banned in the EU since 1st January 2000. This followed a 10- year moratorium on the use of BST in the EU. However, the EU ban does not apply to imports of dairy products (e.g. ice cream) and meat from countries such as the USA where BST is used.
Different Breeds for Different Needs [2]
Dairy cattle are breeds that have been developed to produce milk whereas beef cattle are bred and selected primarily for the production of meat. Dual-purpose breeds do exist and they have been selected for both meat and milk production. In the last 20 years the genetic make up of the UK dairy herd has changed and is still changing. Cows are larger, earlier maturing, are producing far more milk and are more efficient at converting feed into milk.
As it is the birth of the calf that causes milk production, it is critical for the farmer that the cow becomes pregnant again during lactation and produces the next calf one year after the previous one. The average length of productive life of a dairy cow is between four and five lactations, although this varies from one or two to over ten. Since the fifties artificial insemination (AI) has increasingly replaced natural service.
Embryo transplants (ET) are also being developed. A surrogate mother may have difficulty delivering, since the foreign calf is often larger than nature intended. When this happens, a rope or chain is attached to the calf's forelegs, and, with a winch-like device the newborn calf is pulled from the womb. Unnecessary suffering for both cow and calf.
Regular Calving [3]
A high annual milk production per cow is dependent on regular calving at about 12- month intervals. Poor reproductive efficiency leads to longer calving indices and a reduction in milk sales per cow per annum. It also leads to an increase in the number of cows culled for failing to conceive. On average, in the UK, only about 85 cows calve per annum for every 100 cows available for breeding. Over thirty-five per cent of all cows culled are disposed of because of reproductive disorders.
Obtaining Semen [4]
Photographer Henry Heap visited the Milk Marketing Board stud bull operation in Mid Wales. He provided Turning Point magazine with a complete set of photographs and commentary of his visit. "A large, handsome, tan bull stood stock still, tethered by the ring tethered through his nose to what looked like a giant circular clothes line or some grotesque merry-go-round. He was kept so motionless by a rubber hood that covered his eyes, which had a similar effect to that of hooding a falcon. A worker commented that the bull would stay still all day if they left the blindfold on. However, this bull was not the source of the semen, but instead what is known as a 'teaser'. The stud bulls are led out by the nose one at a time to mount the motionless hooded bull. After they have mounted the teaser their penis is diverted into a leather vagina which is used to collect the semen. As soon as the process is complete, another bull is led out. The hood keeps the teaser bull stationery for each successive beast to mount. These stud bulls never even see females.
Embryo Transfer [5]
During embryo transfer an embryo can be flushed from the uterus of a genetically superior cow and implanted in a receiver cow of so-called 'poorer quality' for foetal development. Embryos are also taken from dead cows at the slaughterhouse.
Hormone treatment is used to induce multiple ovulation and the cow is then inseminated. A few days later several embryos can be flushed from her. For both embryo collection and implanting the cow receives a local anaesthetic injection in the tail. Embryos of the desired breed can then be used. ET maximises the number of offspring from selected breeding females and maximises profit.
Do-it-yourself embryo transfer is now taking place in the UK. Courses are run to train in direct embryo transfer techniques using the quick-thaw method for frozen embryos. Although vets are not required to be present at the time of transfer, they must check each animal is suitable for implantation.
Farmers genetically improve the herd by using techniques such as MOET (multiple ovulation embryo transfer) which involves inducing a genetically 'superior' cow to produce up to 20 embryos rather than one.
Oestrous detection [6]
For ease of management, farmers prefer cows to calf at the same time. They, therefore, need to detect when cows come into oestrous. The oestrous detection rate (ODR) is the number of cows observed in oestrus during a 3 week period, in relation to the number of cows expected to be observed. The average ODR on farms is about 60%...One alternative is to synchronise the oestrous period of several animals by injections of prostaglandin or administration of progesterone as an impregnated intraveginal coil implanted for 9-12 days.
Artificial Insemination [7]
Artificial insemination (AI) now accounts for around 75% of British cattle births. The cow is tied up and one hand of the inseminator manipulates the cervix through the rectum wall whilst the other discharges semen into the vagina and cervix using an inseminating gun.
A regional manager with AI firm Genus the problems associated with the procedure. "Placing a quarter of a cc of diluted semen into an area as small as a penny coin, when the target area is inside 500kg of unco-operative cow, requires a high degree of expertise. The more the cow is able to move about, the harder it becomes to hit the target. Poor handling facilities cause stress to you, the cow, the inseminator and both our bank balances."
Natural service by bulls is still used, but the risk of slowing down genetic progress, and the danger of handling bulls means farmers mainly use AI.
Invasive Procedures
There are many invasive procedures carried out on farm animals that the general public rarely witness. One of many includes making sure the cow is in calf. This is carried out using an ultrasound device much like a small tv set with a long thick wire attachment. A vet will insert their hand and arms length into the vagina of the cow. The animal is held in a holding device to keep her still. The screen shows the small calf in the middle of a dark shaped uterus. Herds usually calve at the same time (due to human intervention) so all the cows on the farm will usually be checked at the same time.