Effects of Two Commercial Diets on Several Reproductive Parameters in Bitches: Note Two—Lactation and Puppies’ Performance

SIMPLE SUMMARY: Pregnancy dramatically changes the metabolic status of bitches. As a consequence, malnutrition negatively affects both reproductive parameters and survival rates of puppies. Therefore, before mating and conception, as well as during pregnancy and lactation, it is necessary to satisfy the bitches’ specific nutritional requirements. The present study aimed to compare the effects of two diets, Control (CTR) and Experimental (EX), which differ mainly as regards ingredients, energy, and protein contents, and which were administered to bitches of medium and large size from two months before the expected onset of proestrus up to 30 days after delivery. Bitches’ weight, body condition score, litter size, milk yield and quality, and puppies’ growth were evaluated. Considering the performance of the bitches and the puppies, it would seem that both the diets are adequate for bitches at these stages of their life cycle. In fact, after 30 days of lactation, all tested bitches showed a healthy status. Moreover, both the percentage of newborns mortality and puppies’ growth kinetics fell within the normal physiological range for the species. ABSTRACT: The study aimed to compare two diets, Control (CTR) and Experimental (EX) (mainly differing as regards their ingredients, energy, and protein contents) administered to medium and large-sized bitches from two months before the expected proestrus and up to 30 days after delivery on mothers’ weight, body condition score, litter size, milk quality, and puppies’ growth. No differences were found for body weight during pregnancy, even if the BCS after delivery was significantly (p < 0.01) higher in the EX group than in the CTR one. Concerning the size effect, the percentage of weight gain on the initial body weight was double in medium-sized dogs compared to large dogs (p < 0.01). The number of puppies per litter was significantly higher (p < 0.05) for the EX group compared to the CTR one. Concerning puppies’ weight, the CTR group showed a significantly (p < 0.01) higher body weight from the 21st day of life due to the significant (p < 0.01) higher daily weight gain during the suckling period. Considering the performance of bitches and puppies, both diets seem useful for these stages of their lives. In fact, after 30 days of lactation, all tested bitches showed a healthy status and both the percentage of newborns mortality and puppies’ growth kinetics fell into the normal physiological range for the species.