There are a lot of different (and outdated) practices and theories about how to de-worm your horse. Internal parasites = a significant threat to the health of horses. They can cause extensive internal damage without you even realizing your animals are heavily infected. Effects of internal parasites range from not putting on weight, dull coat, reduced appetite, mild colic or anxiety and an itchy tail head. If left untreated symptoms can progress to include diarrhoea, anaemia, lowered ability to exercise (e.g. lethargy), susceptibility to infections, coughing and significant or recurrent colic. If still untreated parasites can cause pneumonia, emaciation, severe and debilitating diarrhoea, permanent organ damage and colic, it is possible that some of these could lead to death.
Types of worms in horses
While there are numerous parasites that can infect horses the most common internal parasites seen in horses are strongyles (large and small), large roundworms (ascarids), pinworms, bots and tapeworms.
Strongyles - There are large strongyles and small strongyles
Adult large strongyles are found in large intestines. Females deposit large numbers of eggs that are