Round wormsRound worms

Life cyleLife cyle

What are they? What are they?

Roundworms are big worms. Typically they Roundworms are big worms. Typically they are white, about the diameter of a spaghetti-are white, about the diameter of a spaghetti-strand and about 4 inches in length.  Often strand and about 4 inches in length.  Often times kittens or puppies vomit one up or we times kittens or puppies vomit one up or we are horrified when we see them in the feces.are horrified when we see them in the feces.

Kittens or puppies may be born with Kittens or puppies may be born with roundworms! We know that Roundworm roundworms! We know that Roundworm larva are tiny enough to migrate through larva are tiny enough to migrate through the placental blood supply to the fetal liver the placental blood supply to the fetal liver or lungs. Soon after birth the juvenile or lungs. Soon after birth the juvenile roundworms begin migrating from the liver roundworms begin migrating from the liver and lungs to the intestine where they grow and lungs to the intestine where they grow to adults and begin laying eggs. Within to adults and begin laying eggs. Within three weeks after birth, puppies and kittens three weeks after birth, puppies and kittens can begin shedding roundworm eggs into can begin shedding roundworm eggs into the environment. the environment. 

A second source of infection is through the A second source of infection is through the mother's milk - Roundworm larva can gain mother's milk - Roundworm larva can gain entry into the mammary glands and then be entry into the mammary glands and then be passed to the puppies or kittens as they passed to the puppies or kittens as they nursenurse

A third possibility is if the young animal A third possibility is if the young animal should eat an embryonated egg found in should eat an embryonated egg found in fecal contamination of food or water bowls, fecal contamination of food or water bowls, the nesting box or other environmental the nesting box or other environmental sources. The egg hatches within the intestine sources. The egg hatches within the intestine and a "Blood-Lung" migration begins as and a "Blood-Lung" migration begins as described below.described below.

dogsdogs

There are two species of roundworms There are two species of roundworms affecting dogs and puppies: Toxocara canis affecting dogs and puppies: Toxocara canis and Toxascaris leonina. Both are treated and Toxascaris leonina. Both are treated with the same with the same medicationmedication protocol so when protocol so when eggs are seen on a fecal flotation exam, it is eggs are seen on a fecal flotation exam, it is not necessary to determine which species is not necessary to determine which species is present.present.

Regular deworming is especially Regular deworming is especially recommended for dogs that hunt and might recommended for dogs that hunt and might consume the flesh of hosts carrying worm consume the flesh of hosts carrying worm larvae. Puppies are frequently simply assumed larvae. Puppies are frequently simply assumed to be infected and automatically dewormedto be infected and automatically dewormed

. If a dog or puppy vomits up a worm, there is . If a dog or puppy vomits up a worm, there is a good chance this is a roundworm (especially a good chance this is a roundworm (especially in a puppy). Roundworms are long, white and in a puppy). Roundworms are long, white and described as looking like spaghetti. described as looking like spaghetti. Tapeworms can also be vomited Tapeworms can also be vomited

Worm Species in CattleWorm Species in Cattle

Cattle host over 14 different species of gastro-Cattle host over 14 different species of gastro-intestinal roundworms. Different species live in intestinal roundworms. Different species live in different locations in the intestine. As there are different locations in the intestine. As there are usually just a few of these roundworms present, the usually just a few of these roundworms present, the harm they cause is not always apparent and can be harm they cause is not always apparent and can be difficult to assess.difficult to assess.

Four species live in the abomasum: Four species live in the abomasum: barber pole worm (barber pole worm (Haemonchus placeiHaemonchus placei) ) brown stomach worms (brown stomach worms (Ostertagia ostertagiOstertagia ostertagi and and O. O.

bisonisbisonis) ) threadworm (threadworm (Trichostrongylus axeiTrichostrongylus axei))

Life Cycle of Roundworms cattleLife Cycle of Roundworms cattle

Although some details vary, the life cycle of Although some details vary, the life cycle of all the gastro-intestinal roundworms of cattle all the gastro-intestinal roundworms of cattle follows a similar pattern (Figure 1):follows a similar pattern (Figure 1):

1.Female roundworms lay microscopic eggs 1.Female roundworms lay microscopic eggs that pass in the manure of cattle.that pass in the manure of cattle.

2.Within a few days, a free-living larva 2.Within a few days, a free-living larva develops and hatches from the eggdevelops and hatches from the egg

.3.The hatched larva develops through a second, and .3.The hatched larva develops through a second, and then a third stage where it becomes capable of then a third stage where it becomes capable of infecting cattle. Larval development on pasture takes infecting cattle. Larval development on pasture takes only a few days in warmer months, but takes several only a few days in warmer months, but takes several weeks during cooler weatherweeks during cooler weather

.4.Cattle become infected with roundworms as they .4.Cattle become infected with roundworms as they graze on pasture or by ingesting food or water graze on pasture or by ingesting food or water contaminated with manure containing infective contaminated with manure containing infective larvae.larvae.

5.The larvae mature in the intestine and then mate. 5.The larvae mature in the intestine and then mate. The females begin shedding eggs within two to four The females begin shedding eggs within two to four weeks after being ingested by the cow.weeks after being ingested by the cow.

When do Cattle Become Infected?When do Cattle Become Infected?

Roundworms live for approximately one year Roundworms live for approximately one year in cattle. As the previous year's adults die, they in cattle. As the previous year's adults die, they are replaced by a new generation of parasites. are replaced by a new generation of parasites. This stage generally occurs from June to This stage generally occurs from June to August. This annual cycle has two high points August. This annual cycle has two high points for egg output: one in the spring and one in the for egg output: one in the spring and one in the late summer/early autumn late summer/early autumn

Life cycle horsesLife cycle horses Lifecycle of the common internal parasites    Lifecycle of the common internal parasites   

Worms living in the tissues and the gut are true Worms living in the tissues and the gut are true parasites, using the horse’s body as a source of parasites, using the horse’s body as a source of nutrition and lodging. Initially, minute larval stages nutrition and lodging. Initially, minute larval stages migrate through the gut wall and undergo migrate through the gut wall and undergo development (moults) within the body tissues, blood development (moults) within the body tissues, blood vessels and organs. Even a small number of worms in vessels and organs. Even a small number of worms in these stages can cause severe and permanent internal these stages can cause severe and permanent internal damage. Unfortunately, during this migratory period damage. Unfortunately, during this migratory period (up to 6 months for Bloodworms) the larval stages are (up to 6 months for Bloodworms) the larval stages are not controlled by all worming compounds.not controlled by all worming compounds.

The worms do not multiply in the horse’s body The worms do not multiply in the horse’s body but through microscopic eggs passed in the but through microscopic eggs passed in the manure. Studies have shown that up to 99% of manure. Studies have shown that up to 99% of a worm population exists as eggs or larvae on a worm population exists as eggs or larvae on the pasture or in stable bedding. Worm eggs the pasture or in stable bedding. Worm eggs either hatch to produce minute larvae either hatch to produce minute larvae (Bloodworms, Small Redworms) or develop (Bloodworms, Small Redworms) or develop into infective eggs on the pasture (Largeinto infective eggs on the pasture (Large

It is important that all persons responsible for It is important that all persons responsible for the health care of horses have an the health care of horses have an understanding of the common worms and how understanding of the common worms and how to control them. Regular worm control of to control them. Regular worm control of internal parasites is important to ensure proper internal parasites is important to ensure proper digestive efficiency and freedom from worm-digestive efficiency and freedom from worm-related conditions.related conditions.

Heavy worm burdens can lead to recurring Heavy worm burdens can lead to recurring colic, poor condition, lack of thrift, chronic or colic, poor condition, lack of thrift, chronic or acute diarrhoea, poor stamina and coat acute diarrhoea, poor stamina and coat condition, and lack of performance in horses condition, and lack of performance in horses of all ages of all ages

Life cycle catsLife cycle cats

There are two species of roundworms affecting There are two species of roundworms affecting cats and kittens: cats and kittens: Toxocara catiToxocara cati and and Toxascaris Toxascaris leoninaleonina. Both are treated with the same . Both are treated with the same medication protocol so when eggs are seen on medication protocol so when eggs are seen on a fecal flotation exam it may not be necessary a fecal flotation exam it may not be necessary to determine which species is present. to determine which species is present. T. T. leoninaleonina can infect both dogs and cats so can infect both dogs and cats so identifying this roundworm might be helpful in identifying this roundworm might be helpful in indicating which pets in the household are at indicating which pets in the household are at risk for further contagion risk for further contagion

HOW DO WE KNOW IF A CAT IS HOW DO WE KNOW IF A CAT IS INFECTED?INFECTED?

Regular deworming is especially Regular deworming is especially recommended for cats that hunt and might recommended for cats that hunt and might consume the flesh of hosts carrying worm consume the flesh of hosts carrying worm larvae. Kittens are frequently simply assumed larvae. Kittens are frequently simply assumed to be infected and automatically dewormed.to be infected and automatically dewormed.

If a cat or kitten vomits up a worm, there is a If a cat or kitten vomits up a worm, there is a good chance this is a roundworm (especially in good chance this is a roundworm (especially in a kitten). Roundworms are long, white and a kitten). Roundworms are long, white and described as looking like spaghetti. described as looking like spaghetti. Tapeworms can also be vomited up but these Tapeworms can also be vomited up but these are flat and obviously segmented are flat and obviously segmented

Life cycle pigsLife cycle pigs

The large roundworm (The large roundworm (Ascaris suumAscaris suum) is found ) is found in the small intestine of pigs and can grow to in the small intestine of pigs and can grow to 400 mm long and 7 mm thick at maturity. 400 mm long and 7 mm thick at maturity.

Heavily infested pigs may have up to 250 Heavily infested pigs may have up to 250 worms blocking the small intestines and the worms blocking the small intestines and the bile duct causing loss of appetite, vomiting and bile duct causing loss of appetite, vomiting and death. In less extreme cases there is reduced death. In less extreme cases there is reduced appetite, poor feed efficiency and slow growth. appetite, poor feed efficiency and slow growth.

PPiigs 6 to 12 weeks old are the most seriously gs 6 to 12 weeks old are the most seriously affected, while mature pigs may carry the affected, while mature pigs may carry the worms without ill effect. Growth rate and feed worms without ill effect. Growth rate and feed efficiency can be depressed by up to 10%.efficiency can be depressed by up to 10%.

The female roundworm is estimated to The female roundworm is estimated to produce more than 300 000 eggs per day produce more than 300 000 eggs per day which are passed in the dung of infected pigs. which are passed in the dung of infected pigs. The eggs can survive for years in moist The eggs can survive for years in moist conditions to infect other pigs.conditions to infect other pigs.

Larvae (immature forms) reach the liver after Larvae (immature forms) reach the liver after hatching from eggs in the small intestine and passing hatching from eggs in the small intestine and passing through the gut wall. Liver damage is seen as white through the gut wall. Liver damage is seen as white 'milk' spots on the surface of the organ. Entering the 'milk' spots on the surface of the organ. Entering the bloodstream, larvae reach the heart and then the lungs bloodstream, larvae reach the heart and then the lungs where they may cause a low grade pneumonia. After where they may cause a low grade pneumonia. After being coughed up and swallowed they mature in the being coughed up and swallowed they mature in the small intestine.small intestine.

The cycle from egg to egg production is completed The cycle from egg to egg production is completed within 2 months. The parasite is confirmed in a herd within 2 months. The parasite is confirmed in a herd by presence of eggs in the faeces and evidence of by presence of eggs in the faeces and evidence of liver damage (milk spot) at slaughter. liver damage (milk spot) at slaughter.