Investigations into the prevention of neonatal Ancylostoma caninum infections in puppies by application of moxidectin to the bitch

The aim of this investigation was to examine whether reactivated Ancylostom a caninum larvae can be eliminated by the administration of moxidectin to p regnant bitches. Four pregnant bitches infected experimentally with 20 009 third-stage larvae of A. caninum were treated subcutaneously with 1 mg moxi dectin/kg body weight on day 55 of the pregnancy (5-8 days before parturiti on). Another lour experimentally infected pregnant birches served as contro ls. The single moxidectin treatment completely prevented lactogenic infecti ons in the puppies. Neither intestinal stages nor somatic larvae could be f ound. The administration of moxidectin caused no local or systemic side-efi ects in the bitches. All 22 puppies of the treated bitches were born health y and remained so during the whole trial period. Beginning during the third week after birth, all 20 puppies of the untreated bitches developed a seve re microcytic, hypochromic anaemia and they revealed a total of 8649 intest inal stages of A. caninum after autopsy.