Investigations into the Prevention of Prenatal and Lactogenic Toxocara canis Infections in Puppies by Application of Moxidectin to the Pregnant Dog

Abstract

Aim of the investigation was to examine whether two administrations of moxidectin to pregnant dogs could prevent pre-natal and lactogenic infections of puppies with reactivated Toxocara canis larvae. Four pregnant beagles, infected experimentally with 20 000 embryonated eggs of T. canis, were treated subcutaneously with 1 mg moxidectin per kg body weight on days 40 and 55 of pregnancy (5-13 days before parturition). One further dam and its puppies served as untreated control. Two applications of moxidectin completely prevented pre-natal and lactogenic infections in the puppies. Neither intestinal stages nor somatic larvae were found in the dams or their corresponding puppies. All puppies and dams of the treatment group remained coproscopically negative until 42 days after parturition. The administration of moxidectin did not show any side effects in the dams. None of the puppies of the treated dams showed any pathological abnormalities. In the untreated dam one adult and 26 somatic larvae of T. canis were detected at necropsy. All puppies of the untreated dam showed a patent T. canis infection from day 28 post-natum (p.n.); 296 pre-adult and adult stages of T. canis were spontaneously eliminated and 51 intestinal stages and five somatic larvae of T. canis were recovered at necropsy. In contrast to the puppies of the treated dams all negative control puppies showed blood eosinophilia after parturition and elevated liver enzyme levels.

Evaluation of the transcription level of the protein disulfide isomerase in different stages from Ancylostoma caninum with a real-time PCR assay

“…The following A. caninum populations were collected from the strain "Hannover" kept at the Institute for Parasitology in Hannover: (a) Third-stage larvae (L3) collected after larval culture of feces of infected beagles according to Roberts and O'Sullivan (1950), (b) adult male and female worms collected from the small intestine of beagles, (c) Hypobiotic L3, collected from NMRI mice experimentally infected subcutaneously with 1,000 L3, wherein for reisolation of the L3, pepsin digestion was performed as described by Herlich (1956) and Krämer et al (2006), respectively, and (d) serum-stimulated L3 after stimulation according to Moser et al (2005).…”

Transplacental exchange of moxidectin after maternal or fetal intravenous administration in sheep

“…In addition, because moxidectin shows a low affinity for P‐gp, the BBB might not be a significant obstacle for the diffusion of the drug to the CNS in the fetus and newborn. Nevertheless, no signs of drug effects are observed at parturition when a subcutaneous dose of 1 mg moxidectin/kg bw, was administered to pregnant dogs at 40 and 55 days after conception, concluding that the drug is well tolerated by puppies and she‐dogs (Krämer et al. , 2006).…”

Treatment and Prevention of Vertical Transmission of Toxocara cati in Cats with an Emodepside/Praziquantel Spot-on Formulation

“…Numerous substances including moxidectin, selamectin, fenbendazole, flubendazole, piperazine, milbemycin and pyrantel have shown their safety and efficacy in removing ascarid infections. In contrast to dogs where diverse studies have focused on the prevention of neonatal infections by T. canis (Kraemer et al 2006), no data are available concerning the treatment of pregnant queens in order to prevent lactogenic transmission of T. cati. The aim of this study was to evaluate the efficacy of emodepside, a novel anthelmintic of the cyclooctadepsipeptide class, in the prevention of lactogenic infections with T. cati and to evaluate its tolerability and efficacy in young kittens infected with T. cati via their mother.…”