Introduction

The swine pathology is similar in different countries and regions due to the industrialization and intensification of the production.

In summary, we can divide the diseases in pigs in four basic areas: digestive processes, respiratory processes, reproductive processes and immune processes.

Finally, in a schematic and precise way, piglets pathology will be developed with diagnostic tables.

Digestive Processes

The bacterial processes are the most common in the digestive pathology of a pig, but can also be caused by viruses (GET, DEV, PPC), fungi (fusariotoxicosis) and parasites (Coccidia, strongyles).

Escherichia coli:

Piglet colibacilosis is caused by E.coli contamination expelled by the mother. This occurs in the first days of life of the piglets, to the whole litter, reaching 100% mortality due to dehydration. In the third week the pig loses the protection obtained from the mother via calostrum, may be sick of colibacillosis, but no so profuse, diarrhoea mortality is below 20%.

Toxaemia: The toxaemia is caused by toxins secreted by colibaciles in the intestine after weaning. The change of diet, leads to intestinal disbiosis, what allows E. coli to colonize the mucosa of the small intestine where it produces its toxins. Depending on the toxin secreted different diseases will be presented:

– Enterotoxin: Colienterotoxaemia

– Neurotoxin: Oedema diseases

– Endotoxin: Shock

Clostridium perfringens C:

Ethiologic agent of entero-haemorrhagic enteritis of weaning piglets (from 2 to 4 weeks). Contamination occurs right after delivery, multiplying the Clostridium in the small bowel mucosa, where depending on the number of toxins , necrosis can be developed in different degrees. Mortality can reach 100% of the litter in 24 hours.

Salmonellosis:

In pig there are specific Salmonella cholerae suis and Salmonella thyphi suis, which cause widespread disease (acute) and gastric diseases (acute and chronic).

It occurs in pigs from 10 to 16 weeks, primary or secondary (with DEV, GET …) The acute form presents with prostration, diarrhea, fever and sudden death, with 50% morbidity and mortality to 100%. The chronic form presents with stunting, diarrhoea, respiratory and zootechnical performance degradation.

Treponema hyodysenteriae:

Anaerobic spirochete producing pig dysentery in the presence of other bacteria such as Bacteroides vulgatus, Fusobacterium mecrophorum and Campylobacter coli. The condition occurs in farming transmitted to piglets from breeding females. Is an inflammation of the intestine of insidious course, associated with muco-bloody diarrhoea and emaciation. Has a high morbidity and low mortality, but produces great economic losses due to significant growth retardation in animals.

Tricotecenes:

Mycotoxins produced by Fusarium fungi, which affects the gastrointestinal mucosa, causing widespread gastrointestinal disorders: vomiting, diarrhoea and ulcerative lesions.

The lessions occur primarily in the intestine, the mucosa appears red (velvet look by trichothecenes), with small ulcers may occur after a process histamine.

The treatment involves the administration of protective epithelial and vitamin A (symptomatic), and as palliative should be administered as a control in the food mycotoxin binders as aluminium-calcium-sodium hydrated silicates (HSCAS)

Respiratory Diseases

The most revealing processes include rhinitis and pneumonia caused by bacteria, viruses, fungi and parasites.

Acute influenza virus (coronavirus):

Disease signs in growing and fattening pigs. The symptoms include: anorexia, apathy, prostration, fever, conjunctivitis, rhinitis, nasal discharge, sneezing and coughing paroxysms.

Process with high morbidity and low mortality. In 5-7 days, so suddenly recover as sick, but produces stunting and worst conversion rates. In reproductive abortions, fertility problems or embryo resorption associated with a high fever.

Aujesky (herpesvirus):

It is also called pig pseudorabies, is currently considered the most important disease of swine. This virus is highly contagious by direct contact, especially through transportation vehicles, aerial jeans, for farmers and veterinarians tools, milk, semen, placenta, fetuses and uterine secretions.

Produces three tables: nervous (piglets), respiratory (bait) and reproductive. Has a high mortality and morbidity.

Mycoplasma hyopneumoniae:

Is the main cause of enzootic pneumonia (purulent catarrhal bronchopneumonia), accompanied by Pasteurella multocida, both are present on all farms making it difficult to produce free pigs.

Mycoplasmas are generally primary germs and mortality is low, unless there is a concurrent infection (Pasteurella multocida).

The infection of piglets is often by carrier mothers. Several of the pigs may have anorexia, dyspnea, fever and lethargy.

Actinobacillus pleuropneumoniae:

Pleuropneumonia producer may take the form sobreaguda, acute, subacute or chronic. In the form of signs sobreaguda include the presentation of the disease, fever, listlessness, anorexia, cyanosis of the skin on the nose, ears, legs and ventral abdomen. Finally, open-mouth breathing and bloody discharge from the mouth and nose. Death occurs within 36 hours of submission of the infection.

Haemophillus parasuis:

Secondary pathogen associated with PRRS virus, causes pneumonia, pleurisy, pericarditis, polyserositis, arthritis, meningitis in pigs in the breeding, weaning and fattening periods.

Clinical signs appear suddenly in one or more pigs: cyanosis of the skin over the extremities, can be observed subcutaneous edema of the eyelids and ears, the affected pigs scream of pain when moving and can have swelling of the joints.

Salmonella choleraesuis:

Causes septicemia, enterocholitis and acute interstitial pneumonia. The signs are anorexia, fever, cough, apathy and often pile up. Salmonellosis is a pathogen for both pigs and human zoonotic potential. Although Salmonella cholreraesuis israrely associated with the contamination of carcasses or pork products.

Atrophic rhinitis:

Produced by Bordetella bronchiseptica and Pasteurella multocida, the first precursor of Pasteurella infection. The latter creates toxins that destroy the turbinates of the pig, to cause a severe inflammation of the nasal mucosa. This will produce the typical deformation of the upper jaw.

This condition presents with violent sneezing, nasal bleeding, lots disparity in significant growth retardation.

Ascaris suum:

Migrating larvae of the roundworm Ascaris suum produce an inflammatory response that may increase pneumonia caused by other pathogens.