Learning objectives
After studying this unit you should know:
1 The problems caused by roundworms in pigs.
2 How to treat and control roundworm infections of the pig.
3 Problems caused in human by pig parasites.
Roundworm infections of the pig
Pigs can be infected with a number of different roundworms.
People who keep pigs can notice large roundworms, 25 - 40 cm long in the
animals' dung. In pigs 2 to 5 months old the worms cause diarrhoea,
weight loss and lung problems. The young worm lives in the liver and
lungs before passing into the intestine. The damage to the lungs can
allow germs to attack and cause coughing and lung in
fections. The young
pig can die.
The worm in the liver of young and adult pigs causes white spots
(milk spot) to develop. Such a liver should not be eaten by humans.
Treatment and control of roundworms
Infected pigs are easily treated by dosing with a suitable
treatment, e.g. piperazine (see R13 Annex 1). The pregnant sow should be
treated before giving birth or she will pass on infection to her
litter. One female worm will produce a million eggs a day which pass out
in the dung. These eggs infect new hosts and can stay in the ground or
the pigsty for up to 5 years.
The pigsty, shelter or pen should be cleaned out and the walls
and floor treated with caustic soda which is left for 2 - 3 days before
washing it off. If infected pigs have been kept out in a field the land
should be ploughed and used for a crop, or as grazing for other animals,
before pigs are put back on it.
Problems caused by pig parasites in humans
Pigs can be infected with a parasitic worm called Trichinella.
The adult worm lives in the intestine while young worms are found in the
muscles (meat). It does not appear to be a problem to the pig. Any
animal which eats the pig meat can be infected with the worm.
Pigs can be infected with Trichinella from eating rats which have
the infection. Pigs will also be infected from contaminated meat so all
meat fed to the animals (e.g. in swill) should be thoroughly cooked.
Thorough cooking of pork will also kill the worm. If humans eat
undercooked pig meat from an animal infected with this parasite they
will become infected too.
If a pig is left to wander around it may eat plants contaminated
with human faeces. In this way the pig meat can become infected with a
tapeworm from humans. If the meat of that pig is not properly cooked
people who eat it can become infected with the pork tapeworm.
Do not allow pigs to wander around free.
Unit 29: Skin infections of pigs
Pigs can be infected with lice and mange mites. Mange can cause
wounds which can become infected and can result in the hide becoming of
no use for leather production. Humans can also catch the mange
infection.
The pig can also be attacked by ticks.
Pigs can suffer from erysipelas (diamond skin disease) which causes diamond shaped discolouration of the skin. |
Learning objectives
After studying this unit you should be able to:
1 Recognise mange and lice infections of pigs.
2 Know how to control and treat mange and lice infections of the pig.
3 Recognise erysipelas in pigs.
4 Know how to control and treat tick infections of pigs.
Mange in pigs
Mange is caused by infection with mites (see Unit 16) and results
in thickening and crusting of the skin. The activity of the mites
burrowing into the skin makes the pig scratch and the wounds caused can
become infected with germs. Mange occurs around the head, ears, legs and
tail but will spread over the body if not treated.
Mange is controlled by spraying, dipping or painting the infected
areas with a suitable preparation (see R15 Annex 1). The pen and
shelter should also be thoroughly cleaned out and washed down. Treatment
should be repeated after 2 weeks.
After working with mangey pigs wash your hands thoroughly and wash clothing too.
If you have a mange problem in your community which you cannot
stop you will need to ask for veterinary advice. To identify the mite
causing the problem the veterinarian will need skin scrapings from
infected animals. Identifying the mite will allow him to decide what
treatment you should use.
Lice and tick infections
Pigs can suffer from infection with dark coloured lice which can
be seen on the animal's body. The lice feed on the skin and irritate the
pig which will scratch and can cause wounds which become infected.
Treatment involves spraying with coumaphos (see R15 Annex 1) and
cleaning the areas where the animals are kept.
Pigs can be attacked by some ticks which take blood. The ticks
may carry other infections to the animals. Treatment can be carried out
by spraying with a suitable compound (see R15 Annex 1) or by removing
the ticks by hand or by touching them with kerosene or a lighted
cigarette. Affected pens should be thoroughly cleaned.
Erysipelas (diamond skin disease)
Erysipelas or diamond skin disease of pigs can kill the animals.
This is an infection of the pig's body which produces recognisable
discolouration on the pig's body. These are reddish diamond-shaped areas
on the skin or the animal may have a purplish colour to the head and
ears. Pigs with erysipelas have a high temperature and do not feed; they
squeal if touched. The animal can die from an acute infection or in
chronic cases the animal survives but suffers from swollen joints and
lameness.
Erysipelas is treated by using the antibiotic penicillin (see R 7 Annex 1). Animals can be vaccinated against the disease.