Age and life stage can change how a coat behaves. Puppies often shed into their adult coat, and seniors may develop a coat that looks duller or sheds more because grooming is harder, skin is drier, or hormones shift. Pregnancy, heat cycles, and post-whelping periods can also temporarily increase shedding as the body reprioritizes resources and the coat resets.
If the change is gradual and your dog otherwise feels well, think in terms of “supporting presentation”: more frequent brushing, a gentler shampoo schedule, and nutrition that keeps skin comfortable. If the change is sudden, patchy, or paired with thirst, appetite shifts, or lethargy, it’s time for a veterinary check to rule out medical causes that can show up first as coat changes.