Trial With Another Drug For Hydatids

Press, Volume CV, Issue 31042, 23 April 1966, Page 8

Trial With Another Drug For Hydatids

Trials with a relatively new drug for destruction of tapeworms in dogs are to be carried out in the Cheviot County beginning about the middle of June. Mr B. M. Taylor, the National Hydatids Council’s South Island field advisory officer, said this week that the Cheviot County Council at its last meeting had decided to allow the National Hydatids Council to carry out these trials with the drug, bunamidine hydrochloride.

In contrast to arecoline hydrobromide, bunamidine hydrochloride is non-purging and destroys the tapeworms within the dog. Where dogs have been treated with arecoline it has been necessary to take faecal samples to determine whether dogs were infected with tapeworms. It is proposed to treat dogs with bunamidine hydrochloride in pill form at six weekly intervals. In this period no tapeworm in the dog will be able to mature and reach the egg laying stage so that use of the drug should facilitate . the breaking of the cycle of the tapeworms within the dog. The drug was developed by the English firm of Burroughs Wellcome initially as an anaesthetic for human beings. Subsequently it was found to be satisfactory for destruction of worms in sheep and about a year ago the company sent a veterinarian to New Zealand who worked with the Medical Research Council’s hydatid research unit in trials to test the efficiency of the drug against tapeworms. Mr Taylor said it had been 'found that it had a fairly 'high rate of efficiency in this role and could be worth further investigation. The National Hydatidsx Council had carried out a field trial with the drug in the Waiapu county on the East Coast of the North Island and the council had since decided to carry out further field trials

on the East Coast of the North ' Island in the Opotiki, Waiapu, Waikohu and Cook counties—in the Waiapu county there was about a 40 per cent incidence of false and true hydatids in dogs compared with about an average of 71 per cent in the South Island and the incidence in other East Coast areas was similar to that in Waiapu. Other trials with the drug were also to be carried out in the Waimea county in the Nelson area, in Dunedin City with pet dogs and in the Cheviot county. Mr Taylor said that one of the reasons why the Cheviot county had been selected for a trial was the high incidence of taenia ovis tapeworms or sheep, measles in 'the area. This was a tapeworm that infected the i muscle in the carcase of a i sheep and could become economically • Important to. (the country as it led to the I complete condemning of ithe carcase, whereas with 'false and true hydatids only ■ the lung and liver organs ' were condemned. The (county has a near average incidence of true and false hydatids and is considered a typical county with a dog population of sufficient size for such a trial. There arc 750 dogs in the area and it is proposed to divide the county into 10 areas each with 75 dogs. Dogs in -five of these areas will be treated with bunamidine hydrochloride at six weekly

intervals and in the other areas they will receive only the normal arecoline hydrobromide treatment. Mr Taylor said it was proposed to write to each farmer in the areas proposed for the trial explaining the purposes and the reasons for the trial and seeking an indication from them whether they would be willing to cooperate. He said that there was no compulsion on them to take part and where farmers indicated that they did not wish to do so their names would be eliminated from the lists and farmers who were willing to cooperate would be added. Subsequently farmers who were prepared to take part in the trial would be notified of the time and day that the officer would be calling to treat the dogs and how the dogs should be prepared. Mr Taylor said it was hoped that the call could be made every six weeks at the same time and on the same day.

it was hoped to cover an area) with 75 dogs in it in a day, ; with 15 minutes being allow-' ed for treatment at each property. It would be! desirable for farmers to be on| hand at the specified time so that the timetable could be' adhered to. As well as being aimed at, checking on the efficiency of' the drug against all, tapeworms in dogs, including taenia ovis, Mr Taylor said it' was also desired Io check on the cost of using the drug) and as the cost of the drug itself was known —about Is a dog per treatment—this was! largely dependent on the number of dogs that an officer could treat in a day. About eight or nine treatments would be necessary a year compared with three with arecoline.

All dogs in the county, including those in the trial, will still be required on dosing strips at the usual fourmonthly intervals for dosing with arecoline hydrobromide. This will enable a comparison to be made of the infection rates in dogs treated with; bunamidine and those that have not been so treated. In all other field trials with bunamidine all dogs are being treated with it and only in Cheviot will there be control groups! to ensure a comparison to be) made of its effectiveness.

Mr Taylor said that this drug would be perfectly safe to administer to hjtches in pup. pups from about three months of age, old dogs and those suffering from chronic heart disease, so it was expected that it would increase by 5 to 10 per cent the numbers of dogs that could be treated. It would be recommended that the night before treatment dogs should be fed milk and carbohydrate rich foods but not a big meal. It would be important that dog owners should be on hand when the officer arrived to do : the treatment, he said, so that details of the dogs could be obtained. In the first instance dogs would also have to be weighed as a strict dosage rate has been laid down in relation to the weight of the animals. Mr Taylor said that

The costs of running the trial will be met by the National Hydatids Council and it will be supervised by Mr G. A. Thomson, chief veterinaryofficer of the National Hydatids Council, while the technical and administrative part of the trial will be carried out by Mr J. Stocks, hydatid control officer for the Waipara-Cheviot area, and Mr Taylor.

After the preliminary work has been completed it is hoped to have the scheme under way by mid June.