A few tips on the weight of the puppy Brittany Spaniel , during its growth: Growth of Brittany Spaniel female: According to its size, the weight of the Brittany Spaniel female at 3 months should be between 12.9 and 16.1 lbs. At 6 months, the Brittany Spaniel female weighs on average between 23.6 lbs for the smallest individuals and 29.6 lbs for the largest individuals. How much must a Brittany Spaniel Female at 1 year? Enter 30.4 and 38.5 lbs. The Brittany Spaniel female will end up growing ...