Anthelmintic control of lungworm in donkeys.

The research explores the effects of an anthelmintic treatment on lungworm infections in donkeys and the rate at which the infections are re-established after treatment.

Study Design and Initial Observations

• The study began with the observation of 259 donkeys in April 1979. Their faecal samples were examined to classify each animal’s level of lungworm larval excretion (whether they were negative, low positive, or high positive).
• The researchers observed a control group (which was not treated) of 126 donkeys, whose lungworm excretion increased from 80% in April to 91% in October. Furthermore, the individual faecal larval output of donkeys increased resulting in 59% of donkeys being classified as high positives in October, compared to 20% in April.

Treatment and Results

• The treated group of 133 donkeys received 3.5 g of mebendazole daily for five days in April. As a consequence, there was a drop in the number of lungworm excretors from 66% before treatment to 23% one month after treatment.
• The treated group was allowed exposure to infected pastures throughout the summer. Despite this exposure, the number of excretors remained comparatively low.
• By October, patent infections were only re-established in 15% of the donkeys that had been negative after treatment. This indicates the relatively long-lasting efficacy of the treatment in preventing reinfection, even when individuals are exposed to an infected environment.

Key Observations

• This research suggests that the daily prescription of 3.5 g of mebendazole for five days is an effective way of controlling the number of lungworm larvae in donkeys.
• The treatment not only reduced the number of lungworm excretors immediately post-treatment, but also kept the numbers comparatively low even months after exposure to infected pastures.
• This research significantly contributes to the understanding of lungworm in donkeys and the potential for long-term control of such infections via anthelmintic treatments like mebendazole.