The sickness rarely leads to death, but causes considerable discomfort, painful symptoms and sensations in pigs, and high costs for the economy. We suggest you a folder of the major worms, which can be found on worldwide pig farms.

Many are not taking the problem of worms seriously, but in vain. In the U.S., for example, the annual pig losses from these pests are estimated at $250 million (RO Myer, JH Brendemuhl, 2012). They weaken the animals, stealing essential nutrients and damaging vital organs. As the result – we have atrophied and sick pigs, which effects the farm profits. Therefore, the task of each pig-tender - to know about the main helminths and methods of dealing with them. Here's threadworms (nematode) dossier that are often found on pig farms.

Large White Worms or Ascarids (Ascaris Suum)

The life cycle: This is direct. It takes 2-8 weeks for the larva to develop inside the egg and become infective. The eggs after ingestion hatch in the intestine, the larvae migrate through the wall and via the blood enter the liver. They then migrate through the liver to the lungs, finally reaching the trachea where they are coughed up, swallowed and returned to the small intestine to develop into adults. The cycle from egg to egg production is completed within two months.

Clinical signs Large numbers of worms in the intestine absorb food and interfere with digestion. As the larvae migrate through the liver, liver damage (milk spot) results in condemnations at slaughter. The liver lesions heal in 5-6 weeks.

Heavy larval migration through the lungs causes coughing and pneumonia and may activate latent respiratory diseases. Both growth rate and feed efficiency may be depressed by up to 10%.

Diagnosis: This is confirmed by the presence of eggs in the faeces and evidence of liver damage (milk spot) at slaughter.

Management control and prevention Contaminated pens are the most common source of infection hence the adoption of all-in all-out strategies is important in control.

Read more about the life cycle, clinical features and diagnosis of helminths:

• Nematode Strongyloides ransomi

• Trichuris suis

• Oesophagostomum dentatum

• Macracanthorhynchus hirudinaceus

• Hyostrongylus rubidus

• Stephanurus dentatus

• Metastrongylus apri

• Trichinellaspiralis

Also, find answers to questions:

1. How to detect worms in pigs?

2. How to interpret the number of eggs in feces?

3. How to value age of pigs and certain clinical signs?

4. How to hold a post-mortem examination?

All details can be found in "Profitable Pig Production» № 2 (14), 2013.