Disease | Viva!


Diseases are running rife through Britain’s pig factory farms. This means that animals are suffering sometimes excruciating pain, and that powerful drugs are given through most of the pigs’ life. Filthy conditions, overcrowding and stress all ensure that factory farms remain bug infested.

“Many producers do not appreciate the massive effect stress can have on disease.... Intensive production and even straw based systems do exert a certain amount of stress on pigs.” Dr Kees Scheepens, veterinary manager, PIC (Europe’s biggest pig breeding company) (13)

Even Paul Blanchard, manager of the Meat and Livestock Commission’s Stotfold Pig Development Unit admits:

"pigs are kept in less than ideal environments, often in high dust and ammonia which can cause respiratory diseases”...and that “many units have created a cycle of disease”. (18)

Here are some of the most common or important diseases and their causes. Veterinary dictionaries and Pig Diseases by Professor DJ Taylor provide more detailed information (32).

Early Weaning causes Disease

Weaning should be a gradual process at 12 weeks, however almost all UK farms wean piglets abruptly at three to three and a half weeks. The digestive capacity of the pig has not developed until 8 weeks, so early weaning means that piglets have great difficulty coping with solid food.

According to Charles Sheppy of animal feed company, Finnfeeds, when weaned early, disease resistance is low, temperature needs are high and the piglet “has a strong emotional bond to the sow.” (19) Breaking this bond causes severe stress to the mother and baby - making both more susceptible to disease.

At weaning the piglet is confronted with a sudden large proportion of non-milk food and the levels of digestive enzymes which break down these products are low. Sheppy says:

“As a result many young pigs have considerable difficulty digesting their feed from weaning until two months of age. This can result in large amounts of undigested food reaching the large intestine which allows bacteria, some harmful to the pig, in the hind gut to ferment this extra food and grow. These organisms can damage the gut lining and cause scouring.” (19)

Scouring (severe diarrhoea) is a major problem across Britain’s pig farms. In an attempt to counteract the problem, piglets are given drugs on a daily basis (see later.)

According to Dr Philip Baynes, pig products manager at Trouw Nutrition the piglets in the UK are:

“...weaned at a time of peak vulnerability. At around three weeks of age, the antibodies supplied from the sow as colostrum in the milk are at their lowest. The piglet however, will not have established an active immune system in order to cope with any disease challenge, thus rendering it much more susceptible to infection.” (23)

Also the young pig does not produce the enzymes to digest fibre. Fibre from wheat and barley can reduce uptake of nutrients and cause non-specific colitis.

Early weaning encourages pigs to injure one another and promotes disease - meaning continued reliance on antibiotics and other medication.

Pig Injuries can cause Disease

As well as being susceptible to many diseases, pigs in confined, intensive systems face injury from each other. This is from so-called 'vices', including tailbiting, and ear and flank chewing.

An important factor in the development of such 'vices' is greasy pig disease or exudative epidermitis. It affected 17% of UK pig herds in 1994 and killed more than a third of in one outbreak in non-immune herds (32). The disease may kill up to 90% of younger pigs affected. A skin infection or wet eczema begins on the top of the tail or ears, often started by a combination of feed contaminating the skin and splitting of the skin caused by injury from eg bites, rough concrete flooring. Newly weaned pigs are often put on flat decks which has a rough surface and no bedding. The injuries allow Staphylococcus hyicus to invade and cause infection. Other pigs are attracted to the lesion and eventually this leads to biting.

The Greenmount College management notes state that:

'this situation is particularly apparent when pigs are first weaned into flat decks or nurseries or when they are moved into second stage accommodation particularly if mixing takes place. Other diseases such as pneumonia can result in disadvantaged pigs being traumatised by others'. (29)

Treatment involves determining the antibiotic sensitivity of the Staphylococcus hyicus if this is part of the problem and medicating feed for 7-10 days, injecting traumatised pigs with long-acting antibiotics, management control and prevention. (29) The notes add 'if Staphylococcus hyicus infection is part of the problem, there will usually be a very good response to in-feed medication with tetracyclines'.

Respiratory Disease

The VLA (Veterinary Laboratory Agency, Surrey) shows that pneumonia has increased by 27% since 1994 (15). Other respiratory diseases are in decline but Pig Farming magazine states that the declining number of vet samples now sent for analysis could be hiding the facts. Nigel Lodge, Pharmacia and Upjohn veterinary adviser, says respiratory disease is possibly the most important disease threat to pigs.

Major respiratory pathogens recorded by the VLA over the past five years are:

Actinobaccilus pleuropneumoniaae (APP), Haemophilus parasuis (Glasser’s disease), Pasteurella multicoda (pasteurellosis). Swine flu is now an extremely common virus which often leads to secondary respiratory infections, such as pneumonia.

Dr Stan Done, MRCVS, consultant pathologist at the VLA says:

“Respiratory disease can cause severe damage to the pig’s lungs, drastically reducing production performance.”

The VLA says that disease pressure in recent years has never been greater. Viral infections have weakened pigs immune systems leaving them susceptible to other infections. (15)

Dr Stan Done says that before 1991 the UK had no viral epidemics; since then there has been PRRS (porcine reproductive and respiratory syndrome) and swine flu which along with climate have caused a rise in pneumonia. Northern counties such as Humberside have a higher incidence of disease because they farm more intensively.

Mark Blackwell, animal health division of Antec International states that the picture of respiratory disease has changed dramatically over the past few years from mainly bacterial diseases: enzootic pneumonia, actinobacillus pleuropneumonia, atrophic rhinitis to a variety of complex syndromes.

“Viruses such as PRRS, swine influenza and porcine respiratory coronavirus combined with enzootic pneumonia and other bacteria to produce constant major problems throughout production systems.” (25)


Pleuropneumonia is a highly contagious, often fatal, respiratory disease. It is a major problem in most of Europe and the USA. There have been extensive outbreaks of this disease since 1980 in Britain and reports state that 30 to 50% of all pigs here and abroad are infected. (32)

The disease is caused by A pleuropneumoiae and causes depression, anorexia, high fever or laboured breathing and blood stained froth may be seen at the mouth. It often kills 30 to 50% of the pigs infected. It spreads from pig to pig by contact - making factory farms a suitable breeding ground.

PRRS (Porcine Reproductive and Respiratory Syndrome or Blue Ear)

This viral infection causes laboured breathing, occasional fever, loss of appetite, abortion, increase in live births and many piglets born to infected mothers are weak, splaylegged and die.

Again this disease is widespread in countries that industrially farm pigs. It was first seen in the US in 1987, Germany in 1990 and the Netherlands, Spain, Belgium and the UK in 1991. Surveys suggest that 50% of herds in these countries are infected. (32). The disease spreads within a unit by direct contact between pigs. Nasal secretions are the main source of infection, although contact with faeces in dirty units can also spread the virus. Early weaned piglets are vulnerable to the disease.

Pneumonic pasteurellosis

This bacteria invades already damaged lungs, causing fever, coughing, lethargy, breathing difficulties and sometimes death. It is transmitted by contact and ingestion. According the veterinary microbiolgist, DJ Taylor: “..it is commonest under poor husbandry conditions eg overcrowding, dusty ammoniacal atmosphere etc.”


Scours (severe diarrhoea) is extremely common in pigs. It is caused by many factors - but the list of environmental factors associated with scours is telling.

Pig Farming magazine (69) states that the following factors cause scour:

  • Poor hygiene (eg the common sight of pigs standing in excreta spreads disease)

    Lack of bedding (many indoor units provide no bedding and this leads to reduced temperature control and lack of benefit from roughage intake)

    Unclean bedding (if pens do contain straw it is often filthy and this spreads infection)

    Large group size - leads to spread of disease

    Overcrowding (very common and leads to disease spreading)

    Dirty water or lack of provision

    Poor feed bin hygiene (again common)

In poor environments scours can occur without the major infectious causes being present.

The most common infectious cause of scours in growing pigs are: swine dysentery; PIA (porcine intestinal adenomatosis) or iletis and colitis. Less common causes are salmonella, E coli and parasite infections. Severity is influenced by housing and diet. (Colitis is a vague term which is used to describe varying degrees of scour.) Salmonella may infect a pig with no disease occurring but other types of salmonella cause acute generalised illness and can cause scours in people. (69)


A government report in December 2000 stated that up to 700,000 pigs slaughtered that year could have been contaminated with the salmonella food poisoning bug. MAFF calculated that 23% of the nation’s pigs are affected by salmonella and that 5.3% of carcasses checked were infected. (31)

Salmonella infections (caused by Salmonella enterica) can be serious - causing blood poisoning, acute or chronic enteritis and wasting (mainly in pigs between weaning and 3 months.) The septicaemic (blood poisoning) form kills almost all of its victims. Symptoms of the other forms include diarrhoea, fever, depression, weakness and sometimes paralysis and tremor. And sometimes infections only causes mild enteritis or no symptoms.

There has been huge media exposure of the effects of Salmonella poisoning in people - but rarely mentioned is the pain and suffering of the pigs.

Factory farms may help spread this disease as the bacteria infects young piglets via contaminated faeces. Salmonellae are also in slurry and dust within pig units - some of the indoor farms visited by Viva! were thick with dust and slurry pits had not been cleaned out - the stench pervading every corner of the farms.

Further, live transport and markets transmit this disease. Up to 20% of salmonella-free pigs are infected during transport and at the abattoir lairage from contaminated excreta (57).

Escherichia coli

E coli infection causes blood poisoning in newly born piglets, diarrhoea in newly born and weaned piglets, oedema disease (usually in newly weaned piglets), cystitis and mastitis in adult sows.

The bacteria, E coli, is in every pig. Disease occurs when pathogenic (disease-causing) strains invade a pig herd or when the immune system of a pig is under stress. For example, starvation, lack of water and other forms of stress such as a piglet being taken from her mother too young and put on solids too young disturbs the normal balance and allow disease-causing strains of E coli to flourish in the small intestine and cause disease. (It is known that the white blood cells in the mother’s milk reduce the effect of E coli poisoning.) Another reason intensive pig farming has E coli infections is that:

“Dirty accommodation increases the number of infecting bacteria and makes disease more likely”. (Professor DJ Taylor; 32)

Unnaturally high protein feeds also add to the problem.

There are many strains of E coli and the different pathogenic strains may cause disease in young pigs by several ways, eg:

Producing a poison called enterotoxin (Enterotoxigenic E coli or ETEC); directly invading the small intestine or respiratory tract and causing septicaemia.

Newly born piglets may die within 48 hours from E coli septicaemia and diarrhoea. Outbreaks happen in farrowing sheds where litter after litter can be affected. The disease may affect 70% of piglets born and 70% of the piglets that suffer from diarrhoea may die.

E coli in newly born piglets is caused by factory farm conditions where mothers are moved into filthy farrowing crates to give birth and suckle their young. The crates are metal barred devices that stop the mother sow from being able to walk or even turn around - she therefore has no chance of escaping from the contaminated excreta.

Pathogenic E coli also harm newly weaned piglets. As already explained, early weaning puts piglets under enormous stress. Post weaning enteritis or post weaning diarrhoea occurs within 10 days of weaning. It is estimated that 20 to 50% of all weaned pigs may be affected and the death rate is about 10%. (32)


A shamefully high one third of breeding sows in Britain are culled because of lameness. Worse still, foot lesions are present in 94% of pigs killed for meat in SW England. (33)

Foot rot is exacerbated by the urine soaked, unhygienic conditions in which many pigs live. The lesion of the foot is invaded by bacteria causing it to go septic. The area is often ulcerated and is very painful. If abscesses develop the leg is held off the ground. Secondary abscesses may form in other areas eg the brain, liver and spine.

Lameness is also caused by: overgrown claws (caused by keeping pigs on muddy ground with lack of exercise); laminitis (in boars and heavily pregnant sows) and erosive foot lesions.

Animal production expert, Lean says:

'Sows kept in close confinement and/or on slats may become so lame and in obvious pain that there may be no other recourse but to send them to slaughter, assuming that they are still able to walk.' (1)

(If the animal is killed at the farm, a veterinary certificate has to be obtained for the carcass to be accepted at an abattoir as fit for human consumption.)


This is a painful and debilitating leg disorder that causes lameness in pigs. It is linked to pigs being forced to grow too fast and being kept on hard floors.

Cracks and crevices form in the cartilage layer at the hock, elbow, shoulder and hip joints. (57)

Some degree of it may be present in up to 80% of pigs, according to Professor Taylor of Glasgow University (32).

Swine dysentery

This is an infectious disease typified by mucus and blood laden diarrhoea and loss of condition - pigs have sunken eyes and their ribs and backbones stick out. Some untreated pigs die with death rates varying between 5 and 25% on an infected farm. Other pigs do not grow normally. It infects pigs across the globe, with 11% of UK breeding herds and 5% of rearing pigs diseased. (32) It has been reduced from 30 to 40% by eg separating young weaning piglets from the rearing sites.

Swine dysentery is caused by an anaerobic spirochaete and it is transmitted to healthy pigs by infected faeces, it may spread to 75% of animals on a farm.


Streptococcal meningitis is an epidemic disease across W Europe, US, Canada - all countries with industrialised pig farms. Caused by S Suis, it results in sudden death of pigs that seem in good condition. If the pig is seen alive, he may show signs of incordination, tremor, paralysis and spasms before dying within four hours of showing symptoms. The disease is most common in 3 to 12 week old piglets but is not uncommon in pigs up to 6 months. Bronchopneumonia is increasingly being identified with the disease. The death rate is 1 - 50% in any batch of pigs (32). Once infected “the organism is rarely lost from a herd” (32).

Meningitis infection is spread by pig to pig contact. According to veterinary microbiologist, Professor DJ Taylor:

“Overcrowding, poor ventilation and mixing of pigs from different litters” are factors that assist the bug to infect units. Evidently, these occur on factory farms. It can be spread between farms by clothing and hypodermic needles.

S Suis may be present in the carcase of slaughtered pigs.

Meningitis from pigs can spread to humans. Vets, farmers, abattoir workers, butchers and occasionally people buying pig meat in whom “it may cause a fatal meningitis or septicaemia” (32). Humans are more likely to be carriers than to develop the disease.

Glasser’s Disease

An infectious disease caused by the bacteria Haemophilus parasuis. It occurs in pigs worldwide. It is in 30% of units and has become more serious since another disease, PRRS or blue ear, appeared in British farms.

Early weaned pigs are most susceptible at 3 to 6 weeks old (although older pigs do succumb). The piglet may have sudden fever, anorexia, breathing difficulties and so the piglet extends her head. Animals become arthritic and lame, all joints being painful and swollen. The face may swell and there can be severe nasal discharge and coughing. Piglets may die within 2 to 5 days and the skin may be discoloured red or blue.

Those animals that survive may develop heart failure, meningitis or chronic arthritis.

The disease is spread by contact or aerosol.

PMWS and PDNS - new diseases

Post-weaning multisystemic wasting syndrome and porcine dermatitis and nephropathy are sweeping through East Anglia and SW England. They are viral diseases and efforts to treat them have so far failed (59). PMWS is a new disease reaching the UK in 1999; PDNS has been in the country for 10 years but has only become a problem since 1999.

The main symptoms of PMWS are weight loss and laboured breathing, the pigs may also suffer scours, anaemia and jaundice. 5 to 20% of pigs die from the disease. It affects weaners.

PDNS on the other hand mainly affects finishing pigs, (rarely piglets or adults). It is now killing more pigs than ever before - up to one-fifth - because it is combining with PMWS. (59)

Pig Farming magazine states that early weaning helps spread the disease, and that piglets should not be weaned before 35 days. Filthy pens and feed containers also spread the diseases, as does overcrowding and mixing animals from different farms. (59)

Classical Swine Fever (Hog Cholera)

Classical swine fever (CSF) is a highly contagious viral disease, caused by an RNA type of Pestivirus. It is a notifiable disease in the EU and other areas. It was eradicated from the UK in 1966 but then three outbreaks happened in 1971 near Hull where improperly boiled pig swill was fed; then again in 1986 (again due to pig swill), 87 and 2000. *Pig swill can still legally contain pork products.* (see section on Feed.)

Although the EU is officially clear from CSF, outbreaks have occurred in many countries over the last decade. In 1997, Holland killed 10 million pigs to eradicate the disease. (32)

The virus survives in frozen pork for at least 4 years and in pickled or smoked meat for 3 to 6 months. It is destroyed by heating at 65C for 90 minutes.

CSF makes animals feverish, dull, feel exhausted and it strips their appetite. This is followed by conjunctivitis causing the eyes to stick together, constipation then diarrheoa and vomiting. The skin may redden and there may be widespread haemmorhaging. Adult sows may abort. The poor pigs convulse early in the disease and this is followed by lack of coordination and circling. The animals die in 9-19 days in acute cases and 30 to 95 days in chronic cases.

CSF is transmitted by pigs eating contaminated feed (eg swill), litter or through broken skin. Contaminated vehicles and spreading pig manure can diffuse the disease. The virus is in faeces and urine - in factory farms animals are often forced to lie in both.

CSF is controlled in the EU by a kill-all policy - pigs in contact with diseased animals are slaughtered and buried or burned. They are killed for economic reasons (CSF does not infect people) - so that the UK can continue to export pigs and pig meat. As usual, the tax payer compensates the farmers - in the 2000 outbreak in the UK, farmers received 50% of market value for infected animals and 100% for uninfected animals.

By 24 August 2000, 12,000 pigs were killed in Norfolk and Suffolk.

Foot and Mouth Disease

Foot and mouth is a highly contagious viral disease - although it infects most animals in a herd, it rarely kills more than 5% (except piglets where it may kill up to half).

It is caused by an aphthovirus which can survive in pickled meats for 1 to 2 months and Parma ham for 3 to 5 months. It is not always killed by pasteurisation and it may be in dried milk for years.

Foot and mouth’s tell tale symptom is sudden lameness, the feet being very painful. The pig’s back may arch and be he becomes unwilling to move. Blistering occurs on the nose, tongue, lips and feet - hence the name foot and mouth.

The high concentration of virus produced in the early stages of the disease, before symptoms show, coupled with the large number of pigs crowded together and forced ventilation in factory farms, gives rise to large viral plumes which can travel by air for long distances. The virus may then infect other pigs and cloven-hoofed species such as cattle, sheep, goats and deer.

The virus is also spread by infected animals touching healthy animals, by manure in lorries, markets or farms or carried on clothing or shoes. It is also spread by infected meat in improperly cooked swill. Milk may also be a source of infection.

Pigs do not remain carriers of the disease and are free from the virus 28 days after infection (32). Why then are infected animals slaughtered?

The UK Outbreak of Foot and Mouth

In February 2001 panic hit the nation’s livestock farmers as the first outbreak of foot and mouth disease was announced for 20 years. By 20 May 2001, the number of confirmed cases rose to 1,658 (58). It was reported in the press that the source of the outbreak may have been infected meat fed in swill to pigs at Burnside Farm, Heddon-on-the-Wall, Northumberland (35,36). Robert Waugh, the farmer, stated that he collected school and restaurant waste to swill feed his pigs. Mr Waugh said he had not fed the pigs: “anything that had not served up on bairn’s plates.” (35) Little comfort there as school dinners contain burgers, sausages, mince and other cheap processed meat made from MRM (mechanically recovered meat) a slurry made from chicken and pig bones, testicles, rectum, udders, feet and tails.

Mr Waugh did not report the cases of foot and mouth at his farm - the outbreak was first identified in Essex, at Cheale Meats at Little Warley, where Waugh’s infected animals were sent for slaughter (37, 38). Jim Scudamore, the government’s chief vet said of Waugh: “This is a notifiable disease yet this farm did not notify anyone. From the experts that have looked at the ill animals it is quite clear they have been showing signs of clinical illness for two weeks, the blisters have already broken and healed. With incubation this disease could have been present for 28 days, much longer and a far worse situation than we thought at the beginning of the week.” (37)

On 23 February 2001 Bobby Waugh said: “I honestly had not seen anything wrong with any of the pigs in the last few weeks.” Is that because he didn’t check the animals? Farmers are supposed to check animals daily by law.

It is evident from Viva!’s footage of 18 pig units that many farmers either do not check their animals, or if they do, knowingly leave them to suffer.

Vets declared that Waugh’s farm was the perfect breeding ground for foot and mouth. “Rotting pig carcases had been left with live pigs. Pieces of raw meat were left lying about the farm. The sows gave birth among other pigs and grown pigs were eating piglets.” (40)

Again, Viva!’s footage shows similar obscenities in other pig units across Britain. At most farms dead pigs were either left with cell mates, strewn in gangways with rats running around, in containers filled with thousands of maggots or in various stages of decomposition in open pits. We filmed sows giving birth into faeces; mother sows covered in flies with dead piglets by their side; a mother sow haemorrhaging into the gangway - it was filled with blood when we arrived; dirty yards and filthy sheds that had not been cleaned in years.

And yet, MAFF had visited Burnside Farm one month before this outbreak occurred and given it a clean bill of health! Nothing new there either - Viva! notified MAFF/Trading Standards/Health & Safety Executive about several of the farms we filmed. The results? No action.

Foot and mouth spread from Burnside farm to nearby Prestwick Hall farm, Ponteland, probably by wind. From there 40 sheep were among 3500 sold at Hexham market. The buyer was Willy Cleave, a Devon farmer. He shipped the sheep to Longtown market, Carlisle, a holding centre, and from there to Cleave’s Burdon farm in Highampton, Devon. Sheep from Highampton were taken to Bromham abattoir in Wiltshire where they developed foot and mouth. Other sheep were sold to Hill farm in Llancludy, Herefordshire and at an auction in Northampton. 348 other sheep were exported live to Germany from Cleave’s in Devon, via Dover. (38) Of course infected sheep could have been sent to many other countries - Germany incinerated all sheep from stocks imported from Britain; France slaughtered 20,000 sheep, Spain 2000 and so on. Some countries though had already reexported the sheep. And so the disease continues to spread.

The spread of this disease has highlighted again how live animals are transported hundreds of miles within the UK and for thousands of miles outside - all part of industrialised agriculture. Despite the fact that most people in the UK want live exports banned - the trade in misery continues unabated. So long as it does, diseases will be transmitted quickly and easily across the globe.

The policy to control foot and mouth is slaughter-all. This is purely for commercial reasons. As you’ll have seen from the above, there are nastier diseases than foot and mouth that are running rife through industrial pig farms. However, there is no national outcry about them. Why? Because the animals are left to suffer and die, or are killed on farm; and no exports are affected. The recovered animals are transported, sometimes hundreds of miles, to a slaughterhouse where they are mercilessly knifed and bled to death. Is that a better ending than being shot in the head on farm, as happens with foot and mouth victims?

All the breeding stock that farmers cry over losing are also all destined for slaughter! When their breeding output drops below an ‘efficient’ level, sows (and other animals) are sold for low-grade meat products. Old ewes are still sent from the UK to France for Muslim festivals - where the animals have their throats slit while fully conscious, often with blunt knives. (See Going for the Kill, report on religious slaughter by Viva!.) The intensive farmer’s tears are over feared economic losses, not the animals. They are hypocrites - preying on public sympathy - to pretend otherwise.

Of course, the National Farmers Union fully supports the slaughter policy, as do the farmers. The slaughter-all policy aims to preserve the myth of cheap food and to protect an elite of large-scale farmers. Smaller farmers too have no incentive to keep the animals alive. Their profit margins are small and they don’t want thinner and less productive animals. Not when they receive compensation from the tax payer.

Britain persuaded the EU to adopt a policy to stop foot and mouth becoming endemic. Abigail Wood, a vet and researcher into foot and mouth at the Wellcome Trust, University of Manchester says that the mass slaughter of foot and mouth animals:

“...is purely an economic question. Although an infected animal will recover after a couple of weeks, for quite a long period after they wouldn’t produce as much milk or meat. So there is a loss of productivity”. (41)

There have been vaccines available for 50 years but because there are 80 strains of foot and mouth it is only partly effective. The EU has banned the vaccine because it implies that the disease is endemic. Instead the industry effectively gambles that the cost of an outbreak every 20 years or so will be less than that of losing foreign markets. (42)

Vet, Abigail Wood, neatly sums up the government and many farmers’ attitude:

“Although the killing involves these horrific scenes, in economic terms it’s a quick, complete fix; afterwards you can resume exports. Intensive farming is based on productivity. It’s better productivity-wise to eradicate it completely.” (41.)

In fact the only way we will eradicate these diseases is by ending factory farming, live exports and slaughter.