The PDSA charity says a large number of pet owners in Wales and across the UK aren't feeding their animals the right diet.
The organisation warns that a poor diet combined with a lack of exercise could lead to reduced life expectancy in a pet.
Pet obesity poses not only major health risks such as diabetes, arthritis and heart disease, but sadly also means daily misery for millions of pets who are feeling the strain from carrying too much weight.
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Today will be dry for most of the time with bright spells. It will feel pleasant again, though it will feel less warm than recently.
Figures from the ONS show we are more likely to be a victim of fraud than any other crime.
Outbreaks of rain and drizzle will clear tonight with some late sunshine expected.