Given a natural healthy life, cows can live for twenty years or more. High-yielding dairy cows will typically be slaughtered after three or four lactations because their milk production drops and/or they are chronically lame or infertile.
Lameness, mastitis and infertility
Lameness is painful and a significant welfare problem for dairy cows worldwide. Cows may go lame due to various conditions associated with bacterial infection, such as hoof lesions, sole ulcers, laminitis and digital dermatitis. These conditions can be caused by poor quality floors, ineffective foot trimming, poor nutrition and prolonged standing on concrete floors. Lameness often leads to additional welfare problems such as mastitis and metabolic diseases.
Mastitis, inflammation of the udder, is the painful result of bacterial infection that is prevalent among dairy cows. In a herd of 100 cows in the UK, there could be as many as 70 cases of mastitis every year on average. A cow’s udder can become infected with mastitis-causing bacteria due to contamination of milking equipment or bedding. Therefore cows that are housed for long periods of time are more likely to develop mastitis than those kept at pasture.
Cow infertility is a major productivity problem for farmers with high-yielding dairy cows. It can be caused by nutritional deficiencies, stress and poor body condition, therefore it is often a sign of poor welfare.
Most dairy cows will be kept indoors for part or all of the year. Cows typically have less opportunity to act naturally and exercise when indoors, compared to when they are at pasture, however indoor housing may be necessary during bad weather. Good housing design and management are essential for good welfare. Crowded conditions, poor ventilation and high humidity increase the risk and spread of infection.
Rest is very important to cows, especially during lactation, and they need somewhere comfortable to lie. Cows that are kept on concrete floors with inadequate bedding, or in housing with poorly designed cubicles, will be more likely to develop mastitis or become lame. Hard flooring is also more painful for lame cows to stand and walk on, and cows may slip and injure themselves if floors are wet from excrement.
Cattle are ruminants that naturally graze or browse on grasses and other vegetation, therefore they require lots of fibre in their diet. However, dairy cows that produce high yields of milk require more nutrient-dense diets, so are fed more concentrates and less forages. This leads to a build-up of acids in the rumen (part of the stomach) which, if occurring for prolonged periods each day, causes acidosis. Cows with acidosis often have diarrhoea and can develop laminitis (damage to the feet that causes lameness).
Cows in organic systems receive a diet higher in fibre and have access to pasture during the grazing season.
In the US, many dairy cows are injected regularly with growth hormones (rBST) to increase milk yield. This is illegal in the EU.
Surplus dairy calves
Naturally, calves suckle their mothers for up to a year, and maintain a strong bond with her for several years. However in commercial dairy farming, nearly all calves are taken away from their mother within hours of birth. This causes severe distress to both the cow and the calf, and has long-term effects on the calf’s physical and social development.
Most female calves will be reared to join the milking herd but as male calves cannot produce milk, they are considered surplus to the dairy industry. Male calves will either be shot after birth, or sold to be reared for veal or beef.
Calves destined for the meat industry may be transported for several days over long distances by road and/ship, to rearing facilities which may be in different countries. This is very stressful and calves may be transported when only a week old. They will be hungry, tired, and fearful, and are particularly vulnerable to disease and injury at this age.
Due to cooperation between Compassion in World Farming, the RSPCA and the dairy industry (through the Calf Stakeholder Forum), more male dairy calves are now reared for meat and the number of calves being shot at birth has greatly decreased. There is more work to do – around 95,000 of those born in the UK are still shot every year. There has also been an increase in the production of higher welfare veal in the UK; it is better for calf welfare if consumers of veal choose British rose veal instead of imported white veal.
Slaughtering dairy cows
When dairy cows become less productive or have significant health problems, they may be transported long distances to be slaughtered. This is because few slaughterhouses deal with spent dairy cows.
There are more humane alternatives that take into account the welfare of the cow.