The Vegan Society

Promoting ways of living free from animal products for the benefit of people, animals and the environment.

Cattle Health Problems

Lameness [1]

A report by the UK Government's advisory Farm Animal Welfare Council (1997) stated that dairy cattle lameness is at an "unacceptably high level". Levels of 55 new cases of lameness a year for every 100 cows were found in one study. Lameness is almost always a painful condition, and therefore a major animal welfare issue. Professor Webster states that "Lameness, mainly that caused by painful damage to the foot, is probably the most common single cause of distress to dairy cows at this time. Surveys of cases of lameness treated by veterinary surgeons indicate an average annual incidence of about 4-6%. When cases treated by the farmer are included the annual incidence appears to be about 25%!" He goes on to say that foot lameness is the consequence of a number of distinct pathological conditions, the most important of which are:

The factors that predispose to lameness in dairy cows may be considered under the following headings:

Inspection of the feet of cull cows at slaughter reveals evidence of past or present foot damage in nearly all animals which causes chronic pain. About 90% of cases are associated with the outer claws of the hind feet.

Conformation [2]

The most striking feature of foot lameness in dairy cows is that approximately 75% of cases occur in the abaxial (outer) claws of the hind feet. This is attributed to the conformation of the cow. The distention of a huge udder splays the back feet out. To imagine the problem from the cow's point of view, try walking with a huge pillow between your legs!

Laminitis [3]

A three year study funded by the Ministry of Agriculture, Fisheries and Food examined the effect of straw yards or cubicals and different feeding regimes on incidence of laminitis in Holstein Friesian, first calved heifers. Year one research showed that incidence of white line haemorrhage was increased by the high concentrate diet. Housing in straw yards also reduced sole haemorrhages - but failed to compensate for the high concentrate effects. Clinical incidence of lameness was also higher in heifers on the high concentrate diet. Researcher Dr John Metcalf attributes the increased incidence of sole haemorrhages six weeks post calving in all treatments to stress at calving.

To understand the pain of laminitis it helps to imagine crushing all your fingernails in the door then standing on your fingertips.

Cows suffer by standing in their own shit

"When you have a high incidence of digital dermatitis you have too much slurry [liquid excrement] in contact with the feet." says Dr Murray from Liverpool University. [4]

He adds "Young cattle are susceptible in badly designed yards or cubicles that rely on mechanical cleaning methods. The effects of poor housing are made worse by the spread of bacteria from cow to cow. So it is vital to reconsider ways to keep cows' feet free from slurry."

According to Shropshire vet Clive Norrell the incidence of lameness caused by digital dermatitis is on the increase. Quoted in Farmers Weekly Norrell states that "Digital dermatitis tends to occur in younger and bought-in animals during the winter when cows are in slurry". [5]

Sleeping Rough [6]

Cubicles are common indoor housing systems.

Dairy Farmer reports that "Some heifers make the transition to cubicle living without fuss, others take some persuading. There are producers who use anything from flooded passageways to electric shock devices to prevent cubicle rejection Chapter 4 - Health Problems Inspection of the feet of cull cows at slaughter reveals evidence of past or present foot damage in nearly all animals which causes chronic pain because heifers that continue to lie in the slurry do not last long: dirty cows, trodden teats and bruised hocks all qualify for inclusion on the culling list."

Problems for the farmer connected with over-wintering animals outside include dirty cows, nutrients being diverted towards keeping the animal warm rather than producing milk, food wastage and difficulty observing animals properly (conditions are better in a lighted building). Most farmers, therefore, provide indoor housing for their cows in the winter. Some animals, however, may be housed indoors all year round.

Housing systems do vary but individual cubicles are common, the development of which was spurred on by the need to save labour on spreading bedding and mucking-out. The design of cubicles has not changed significantly in the past 30 years unlike the cow who has become taller and longer. The result is that cows have become too large for the space they have available to lie down. They are also liable to injury from the bars at the rear of the cubicle and sparse bedding or floor cover on concrete can lead to physical injuries. Where the front of the cubicle faces the wall, animals are unable to stand up in the way they would normally do in the open because there is insufficient space for the forward extension of the head and neck. Cows may be unwilling to use the cubicles and prefer to stand in the dunging passage for long periods of time which leads to soft hooves and lameness.

According to Tony Blackburn, lecturer in dairy husbandry at Reaseheath College, Cheshire, " ... pursuing high yields means cows are expected to eat more - particularly on complete diet regimes - spend longer doing so, and as a consequence their feet, particularly the front ones, come under greater pressure."

Disruption of normal behaviour like this incurs stress on the animal and damages their immune system.

University Research

Researchers at the Veterinary School, Liverpool University spent two and a half years, from 1989 to 1991, monitoring dairy cow lameness in around 5,000 cows in Cheshire, Somerset and Wales. Previous studies have relied on the records of veterinary surgeons attending sick animals. In practice, these recorded severe cases only, implying a substantial under-reporting as farmers treated many animals themselves.

Some farms reported as many as 180 episodes of lameness per 100 cows - some cows were treated but became lame again. Others had an incidence level of 40 episodes per 100 cows. The most common causes of lameness were solar ulcers and white-line lesions. Solar ulcers and whiteline lesions are normally associated with winter housing problems but there was little seasonal difference in the incidence level. From the analysis of the work by the Liverpool team came a shocking series of pointers to the high lameness risk unit.

Farms falling into this category tend to have the following problems:

John Hughes, independent dairy consultant says in Dairy Farmer in February 1997 that "... the cow is still the only animal which we expect to walk around in her own faeces ... Walking around in slurry and, where automatic scrapers are used, having her feet bathed in it several times a day has severe health consequences in terms of both lameness and mastitis," he says. Higher yields of milk have led to higher intakes of dry matter and more slurry. Feeding caustic-treated wheat makes the cow drink more water which increases the urine output. Cows have changed, diets have changed, but housing has not.

Slurry is very potent and attacks the horn of the foot of the animals. At the end of the winter housing period, the hoof will have absorbed a third of its weight in slurry and the horn will be noticeably softer.

When a cow lies down she puts one foot underneath her, usually resting against her udder, and a dirty foot can lead to a case of mastitis. Dirty tails are a similar hazard. "Tails tangle into slurry in the passageway and may be washed by the scraper too," says John, adding that he has seen a cow cover herself in slurry with the flick of her tail. [8]

Mastitis

The UK Government's advisory Farm Animal Welfare Council declared that, "Mastitis is a very significant disease of dairy cattle and occurs in all dairy herds." Its 1997 Report quoted a rate of 35-40 clinical cases of mastitis per 100 cows per year. The udder becomes hard and hot with an abnormal discharge. In the recently calved cow the milk is thick, creamy and smells foul. The cow is often lame in one or both hind legs with swollen joints. Body temperature can be high and in some cases pregnant cows will abhort or produce a stunted calf. [9]

Bacteria enters the teat from milking equipment, the parlour area e.g. bedding, flies or the hands of the herdsperson. The body of the cow combats this infection by sending a surge of white blood cells to the udder area. Farmers fight an almost losing battle again high cell counts which are taken regularly to ensure that numbers don't go over a certain figure. If they do milk may be rejected as unsuitable for consumption. [10]

Some farms feed rejected milk to calves and others dump it but as milk has an extremely high pollution potential care must be taken to keep it out of water courses. Mastitis is usually controlled by antibiotics infused into the teat via a tube or syringe.

The New Scientist reports around 4 out of ten cows are affected by mastitis each year in Britain, costing farmers an estimated £120 million. [11] Consultant, Peter Parker, from Lancaster claims in a farming magazine "At least 90% of mastitis problems are milking machine orientated. I am coming across continuous teat end damage and the major cause is liner design. There are very few liners on the market that are not causing horrendous damage to the ends of cows' teats. In this day and age the standard of workmanship is just unreal. It has to be seen to be believed". [12]

One MAFF survey indicates that over one million cows are diagnosed annually with clinical mastitis in the UK. [13]

By increasing the frequency of milking to four times daily, mastitis may be reduced. However, this may increase the possibility of teat damage and infection. Very severe cases can result in death.

A diseased cow, particularly if suffering from mastitis, contributes very high numbers of pathogenic microorganisms to the milk.

Milk Fever (parturient hypocalcaemia) [14]

Milk fever is caused by low blood calcium levels at calving and cows may be the most susceptible when they are producing their top yields from third lactation onwards. Milk fever occurs most in autumn when grass quality wanes, unless a conserved forage supplement is available. If untreated, the cow become progressively weaker and is unable to stand. Suffering from shock and bloating, death often follows in a matter of minutes or hours.

Tuberculosis [15]

Cattle TB is a far worse problem on farms than BSE, says Hugh Black, vice-chairman of the National Farmers Union's animal health committee. Mr Black warns TB is spreading at a worrying rate in Herefordshire, Worcestershire and Shropshire, and is now on the Cheshire border. Badgers have been blamed for the spread of TB but Ruth Murray, who runs the Dartmoor Badger Sanctuary, says "No scientific proof exists to show badgers transmit TB to cattle." The latest Government report does not throw any light on the subject of whether badgers give TB to cattle or whether culling badgers actually helps prevent outbreaks of TB.

Cystic Ovary [16]

Cystic ovaries in dairy cattle are up by 50% across the country, according to Buckingham-based vet Ian Baker. Mr Baker says "Normally 2-5% cows show cystic ovaries but in some herds up to 15% are affected. " The disease is a hormonal dysfunction that leads to large cysts forming on the ovaries. Two types of cyst produce either oestrogen, causing a continuing oestrus, or progesterone which suppresses the cow's reproductive cycle. ADAS's Bruce Cottrill says that the exact cause of cystic ovaries is unknown. But suggestions are that it is genetic, appearing more frequently in high yielders . "Stress could also be a factor as well as nutritional imbalances."

Pneumonia [17]

Vet consultant Dr Alison Gibbs says "Pneumonia in home-bred dairy replacements costs £9.5m a year. Newlyweaned bought-in calves were more vulnerable to infection because of the change in feed and transport stress.

Two thirds of that loss is due to viral pneumonia. To tackle the disease effectively, farmers must quickly establish which of the five different viruses is responsible, Jamie Robertson from the Scottish Agricultural College told visitors at Smithfield. Checking ventilation of cattle buildings is also worthwhile.

Aberdeen research had shown that a third of buildings failed to meet basic ventilation needs. "We found that humidity was far too high - regularly in excess of 90%," said Mr Robertson.

Bullying [18]

Professor Webster states that "There are a number of disturbances to normal behaviour that can occur, particularly when firstcalving heifers are brought into the herd, which can often be attributed to the anti social behaviour of elder cows. The timid, bullied heifer forced out of cubicles to stand and lie in a dung passage is not only distressed but increasingly prone to lameness or environmental mastitis."

Cow Flu or Red Nose (Infectious Bovine Rhinotracheitis) [19]

This, highly infectious disease, is becoming increasingly prevalent. It can cause respiratory disease, abortion, vulvovaginitis and encephalitis in young calves.

Leptospirosis [20]

This bacterial disease is the major cause of abortion in cattle. It can also cause infertility, weak calves, reduced milk yield and is infectious to humans.

Dystokia [21]

Difficult calvings (dystokia) arise in about 5% of births in dairy cattle, although in first- calving heifers the incidence may be over 10%. The result may be a stillbirth.

Endometritis [22]

Endometritis is an inflammation of the uterus which occurs after calving. When severe, the cow goes off her feed, loses condition and becomes very ill. It is an inflammation of the uterus caused by poor hygiene at calving.

Hypomagnesaemia (grass staggers) [23]

Low blood magnesium causes excitability followed by leg spasms and problems with falling over. Death due to heart failure may follow quickly.

An independent survey of practising cattle veterinary surgeons states that 80% claim hypomagnesaemia continues to be a problem in the national herd and farmers could do more to prevent fatalities.

These views are backed by data from MAFF Veterinary Investigation Centres which show no improvement in confirmed cases over the six-year period to 1994 and, while there was a dip in the 1995 figures, provisional figures for 1996 suggest that this may be short-lived.

Scouring [24]

Scouring or loose faeces in cows is commonly seen when diets contain a high protein level and/or a low fibre level. To combat infectious scours due to E. coli infection, a prophylaxis of a proprietary E. coli serum or antibiotics are given. If the calf is not treated death can occur.

Lungworm (husk) [25]

British cows have always been susceptible to lungworm because of the cool, wet climate. It is caused by the worm dictyocaulus viviparus and can lead to debility, weight loss, pneumonia and in serious cases, death. One calf with lungworm can contaminate a pasture with over 30 million larvae.

Displacement of the abomasum [26]

At calving, the abomasum may become displaced causing gas formation. Acetonaemia may follow as a result. Surgery or manipulation through the abdominal wall with the cow lying on its back, may be necessary.

Ketosis (acetonaemia) [27]

A big problem after the cow has calved is ketosis, which occurs because the animal is inadequately fed, and obliged to metabolise her own body fat to make milk. In severe cases cows lose weight, become dehydrated and show nervous, agitated behaviour such as delirium, bellowing and walking in circles.

Professor Webster says that "To achieve in early lactation a milk yield of 35 litres/day the work done by the mammary gland and other organs such as the liver which make substrates available to the mammary gland, greatly exceeds the amount of energy-yielding nutrients that the cow can consume from a properly balanced diet. She must therefore mobilise energy from her own body reserves, chiefly fat. Up to a point this is normal and healthy. However, excessive fat mobilisation leads to accumulation of ketone bodies (ketosis or acetonaemia) and, in many cases, to fatty degeneration of the cells of the liver. The cow then loses her appetite which makes matters worse. Humans with ketosis and liver damage feel extremely unwell and we may reasonably assume the same for cows."

Acidosis [28]

Professor Webster says "Excess intake of rapidly fermented concentrated feeds leads to indigestion, ruminal acidosis and the disruption of the normal rumen microflora. This provokes, at least, acute discomfort and loss of production. In more severe cases the primary ruminal upset can lead to metabolic acidosis and inflammation of the sensitive laminae of the hooves. In its acute form this causes the cow severe and enduring pain. It can also lead to separation of the sensitive and horny laminae, rotation of the hoof and a predisposition to subsequent ulceration of the sole.

The dairy farmer has to achieve a very fine balance between overfeeding and so provoking a digestive crisis and underfeeding and so provoking a metabolic collapse. This problem is not amenable to easy solution by altering the husbandry system; it is an inevitable consequence of the genetic make-up of the highly selected modern dairy cow, be it a Friesian or a Jersey, whose capacity to produce milk exceeds her capacity to process feed."

Bloat [29]

Each year when dairy herds are turned out after winter inside they may suffer from bloat. This is usually caused by eating large amounts of leafy and highly digestible pasture which causes rapid fermentation in the rumen resulting in gas being trapped in bubbles, instead of forming a gas cap in the first stomach which can then be belched free.

Affected animals have a distended body and as the stomach enlarges they become distressed, with rapid breathing. The tongue may protrude and there is some slobbering. When the swollen stomach is tapped it sounds like a drum. Unless cattle are treated promptly they can die.

High Yielding Cows [30]

High-yielding cows are those that produce around 10,000 litres of milk per year as opposed to the more usual 5,000-6,000 litres. A typical Holstein dairy cow may yield 15-25 litres at a single milking. H i g h Yielders have been specially bred and their feed and lifestyle are scrutinised to ensure these high milk yields are maintained. However, being pushed so hard has its drawbacks for the animals concerned.

According to research at the Scottish Agricultural College poor fertility in high yielding dairy cows may be an indication of stress. However, they claim early results suggests there is no link. 1996 was the second year of the three year study into stress in high yielding dairy cows and, while it is too early to provide concrete answers, research suggests this. Dr Birt Nielsen, one of the project members, said "What we are suggesting is that the main factor affecting health is the age of the cow. Quite simply, the older the animal, the more likely she is to have health problems."

More definite results are emerging on lameness. "It is a huge problem in dairy cattle, but it does seem that there is no link between high yields and lameness. Environment is the real cause of lameness."

Recent trends in the dairy industry have moved towards milking three times a day to increase milk yields. Professor claims that ".... some cows, e.g. those milked three times daily, may have insufficient time for rest."

A typical maximum daily yield per cow is 30-40 litres but 57 litres has been obtained in California and Israel. The work her body does is intense and lengthy. Health problems occur in high yielders including hunger, exhaustion, infection, chronic pain and disease. It has been claimed that the overwintered UK cow may feel, simultaneously, hungry, 'full up' and physically tired.

References