EFFICACY OF PYRANTEL EMBONATE, FEBANTEL, AND PRAZIQUANTEL

                                                   AGAINST GIARDIA IN DOGS

 

                                 D. BARUTZKI1, A. SCHIMMEL2, and R. SCHAPER2

 

                             1 Veterinary Laboratory Freiburg, 79111 Freiburg i.Br., Germany

                           2 BG Animal Health, Bayer AG, 51368 Leverkusen, Germany

 

 

ABSTRACT

Giardiasis is recognized as an important disease in humans and in young animals of several species in most areas in the world. The prevalence of Giardia spp. in dogs varies greatly, but has been reported to be very high in breeding kennels and in puppies. Chemotherapeutic treatment is recommended for all infected dogs to cure acute symptoms of giardiasis, to avoid reinfections and to reduce the potential zoonotic risc for man. In Germany nitroimidazole derivates such as metronidazole and recently the benzimidazole fenbendazole are used to treat giardiasis in dogs. The objective of this study was to prove the therapeutic efficacy of pyrantel embonate, febantel and praziquantel (DrontalÒ Plus)a against Giardia spp. in naturally infected dogs under field conditions.

 

A test for Giardia-specific antigen (ProSpectTÒ Giardia Micoplate Assay) performed in dogs from private owners identified 35 dogs between eight months and fourteen years old and 3 dogs between six and fifteen weeks old to be naturally infected with Giardia spp. All 38 dogs were treated orally with combination tablets (144 mg pyrantel embonate, 150 mg febantel and 50 mg praziquantel)a at the recommended dosage on two consecutive days. The therapeutic response was assessed on day three after the last medication by means of the coproantigen test for Giardia-specific antigen. On the third day after the final administration of the tablets 35 of the 38 treated dogs were negative for coproantigen of Giardia and 3 were positive. Signs of toxicosis were not observed in any dog.

 

The results of the study indicate that the combination tablets (144 mg pyrantel embonate, 150 mg febantel and 50 mg praziquantel) a given at the recommended dosage on two consecutive days are effective for treating naturally acquired giardiasis in dogs.

 

 

KEYWORDS

Giardia, dog, therapy, benzimidazole, Drontal Plus, Germany

 

 

INTRODUCTION

Giardia are flagellate protozoa parasitic in man and numerous animal species. The prevalence data of Giardia spp. in dogs quoted in the literature indicate that the incidence of these flagellates varies considerably and depends to a large extent on the composition of the studied canine population. Epidemiological surveys of canine families in southern Germany have shown that infections with Giardia occur far more frequently in puppies and in kennels or in intensive breeding establishments than among older animals, dogs kept individualy as domestic pets or dogs from small breeders (Barutzki et al. 1989). Chemotherapeutic treatment is recommended for all infected dogs to cure symptoms of giardiasis, to avoid reinfections and to reduce the potential zoonotic risc for man. Hitherto giardicidal drugs mostly used in dogs are nitroimidazole derivates such as metronidazole. Following in vitro studies (Edlind et al. 1990, Morgan et al. 1993), which provide a preliminary indication for the efficacy of benzimidazoles against Giardia, the efficacy of fenbendazole (Barr et al. 1994) and a combination of praziquantel, pyrantel pamoate, and febantel (Barr et al. 1998) against naturally acquired giardiasis in dogs could be demonstrated. The objective of this study was to prove the therapeutic efficacy of pyrantel embonate, febantel and praziquantel (DrontalÒ Plus) against Giardia spp. in naturally infected dogs under field conditions.

 

 

MATERIALS AND METHODS

Preliminary examinations for infections with Giardia spp. were performed in dogs from private owners by means of the ProSpecTÒ Giardia Microplate Assay, which uses monoclonal antibody for the qualitative detection of Giardia Specific Antigen (GSA 65) in aqueous extracts of fecal specimens. GSA 65 is a glycoprotein that is produced by Giardia as they multiply within the host intestinal tract. The antigen is present only when Giardia infection is present. A total of 38 suitable dogs (Table 1) with a positive test result (selection criterion) were identified for inclusion in the study.

 

Table 1. Age and bodyweight of the Giardia positive dogs treated with a combination tablet containing pyrantel embonate, febantel and praziquantel


    No.


            Age

    Bodyweight
          (kg)

           No.


            Age

    Bodyweight
          (kg)

     01

            4 years

            34

    20

         8 months

           27

     02

            6 years

            40

    21

         8 months

           18

     03

         2.5 years

            25

    22

       10 months

             6

     04

       12 months

            35

    23

            3 years

             6

     05

          14 years

              8

    24

            5 years

           28

     06

       10 months

            28

    25

       16 months

           44

     07

       15 months

            31

    26

       13 months

           32

     08

       13 months

            24

    27

            8 years

           12

     09

       14 months

            26

    28

          6 weeks

           10

     10

       10 months

            42

    29

        15 weeks

           13

     11

       16 months

            40

    30

        10 weeks

             4

     12

       18 months

            65

    31

            7 years

           29

     13

            4 years

            13

    32

            4 years

           33

     14

       12 months

            38

    33

            2 years

           27

     15

       10 months

            44

    34

            3 years

           30

     16

       12 months

            27

    35

            4 years

           25

     17

       11 months

            20

    36

            3 years

           32

     18

       16 months

            20

    37

       12 months

           30

     19

       19 months

            23

    38

            5 years

           30

 

The dogs were weighed prior to the treatment and treated orally with combination tablets (one tablet per 10 kg bodyweight contains 144 mg pyrantel embonate, 150 mg febantel and 50 mg praziquantel) at the recommended dosage on two consecutive days. The combination tablets were administered to the dogs in a quantity of about ½ tablet / 5 kg bodyweight per day. On day 3 after the last medication individual samples of spontaneously passed faeces from the dogs were collected and examined for Giardia-specific antigen. The efficacy of pyrantel embonate, febantel and praziquantel against Giardia was assessed with reference to the qualitative results of the ProSpecT Giardia Assay for coproantigen by comparing the results before and after the treatment.

 

 

RESULTS AND CONCLUSION

The efficacy of pyrantel embonate, febantel and praziquantel against Giardia was investigated by treating 38 Giardia positive dogs with combination tablets of Drontal Plus at a dose rate of about ½ tablet / 5 kg bodyweight on two consecutive days. The therapeutic response was assessed on day 3 after the final administration of the test product by means of the coproantigen test for Giardia-specific antigen. On the third day after the final dose of the test product 35 of 38 animals (Table 2) were negative for coproantigen of Giardia (Efficacy: 92.1 %).

 

Table 2. Efficacy of Drontal Plus against Giardia in dogs proved by means of coproantigen test



     Dog age

         Number of
Giardia positive dogs
     before treatment

          Number of
Giardia positive dogs
       after treatment

          Number of
Giardia negative dogs
        after treatment

     < 1 year

               14

                 0

              14

     >1 year - 2years

               10

                 1

                9

     >2 years

               14

                 2

              12

     Total

               38

                 3

              35

 

Signs of toxicosis were not observed in any dog. The present study, through the use of the coproantigen test, which detects the antigen GSA 65 excreated by trophozoites, was able to prove that metabolically active trophozoites of Giardia were not present in 35 out of 38 tested dogs after the treatment. The results indicate that the combination tablets (144 mg pyrantel embonate, 150 mg febantel and 50 mg praziquantel) given at the recommended dosage on two consecutive days are effective for treating naturally acquired giardiasis in dogs.

 

 

LITERATURE CITED

 

Barr, S.C., D.D. Bowman, and R.L. Heller 1994. Efficacy of fenbendazol against giardiasis in dogs. Am. J. Vet. Res. 55: 988-990

 

Barr, S.C., D.D. Bowman, M.F. Frongillo, and S.L. Joseph 1998. Efficacy of a drug combination of praziquantel, pyrantel pamoate, and febantel against giardiasis in dogs. Am. J. Vet. Res. 59: 1134-1136.

 

Barutzki, D., R. Gothe, and I. Reichler 1989. Zur Endoparasitenfauna bei Welpen und ihren Mutterhündinnen in Süddeutschland. 35. Jahrestag. Fachgruppe Kleintierkrankheiten, Dtsch. Vet. Ges., 12.-14.10.1989.

 

Edlind, T.D., T.L. Hang, and P.R. Chakraborty 1990. Activity of the anthelmintic benzimidazoles against Giardia lamblia in vitro. J. Inf. Dis. 162: 1408-1411.

 

Morgan, U.M., J.A. Reynoldson, and R.C.A. Thompson 1993. Activities of several benzimidazoles and tubulin inhibitors against Giardia spp. in vitro. Antimirob. Agents Chemother. 37: 328-331.

 



a DrontalÒPlus, Bayer AG