Evaluation of the tolerance of a combination of milbemycine oxime and praziquantel in breeding, lactating bitches and in newborn puppies

The objective of the present study was to evaluate the tolerance of a combination of Milbemycine Oxime and Praziquantel (Milpro®, Virbac, Carros, France) in pregnant dogs and their newborn puppies.

For this purpose, 15 breeding bitches of different age (2-8 years), breed and weight (8-78 kg) were treated every 2 weeks with Milpro® and followed during gestation and lactation. The product was also given to puppies every 2 weeks, from 2 to 8 weeks of age. The optimal mating time was determined and gestation was confirmed at third week. An examination of females and fetuses and an assessment of blood parameters was then performed every 2 weeks.

During gestation, no side effects occurred. Ultrasound examination of all pregnant bitches revealed normal development of embryonal sacs (evaluated by Inner Chorionic Cavity Diameter) and then fetuses (evaluated by Biparietal Diameter and Heart rate). Length of pregnancy was normal and varied from 64 to 69 days. The progesterone concentration and blood parameters in treated pregnant bitches were normal during gestation and lactation. Some values out of range could be observed transiently with no clinical implication. Parturition was physiological in 14 bitches but one Great Dane dog required a C-section due to the presence of 2 dead puppies. Retention of placenta was noted in one bitch and another one showed purulent discharge five weeks after parturition which was resolved by antibiotic administration. The mean litter size at delivery was 5.93 puppies per bitch (2 to 12). The puppy mortality rate from birth to weaning was in normal range (10/90: 11%). Five puppies had mild and transitory gastrointestinal signs (diarrhea or parasites in feces). Development of puppies until weaning was normal.

Administration of Milpro® every other week is safe for pregnant and lactating bitches and for puppies from 2 weeks of age.