If you've rescued a litter of orphaned kittens, it's important to determine their age so you can decide on how best to care for them. While your vet is the preferred person to consult with about this, there are signs you can look for to estimate their ages yourself.
Check your little ones for signs of an umbilical cord on their tummies. The remnants of their umbilical cords fall off around the time the kittens reach 3 days old.
Inspect your kittens' eyes. A kitten less than 1 week old will have closed eyes. The eyes begin to open between 1 and 2 weeks old. Once your kittens' eyes are open, they will be blue in color. This changes to another color, such as yellow or green, around 6 to 7 weeks old. The exception to this occurs in naturally blue-eyed cats, like the Siamese or Himalayan.
Look at your kittens' ears. Their ears start to unfold between 3 days and 1 week old. Your kittens' ears will stand up straight when the kittens reach approximately 3 weeks of age.
Inspect your kittens' teeth, if they have them. Your little guys will get their baby teeth around 3 to 4 weeks old. They should have all 26 of their baby teeth between 6 and 8 weeks old, according to PetPlace. Kittens grow their 30 adult teeth when they reach between 4 and 6 months old.
Observe your kittens when walking. Kittens under 2 weeks old will crawl around, while those between 2 and 3 weeks old are able to walk, though they will be a bit wobbly when they do. Between 3 and 4 weeks old, the little ones can run around and those older than 1 month old will be much steadier on their feet.
Compare the size of the kittens to that of an adult cat. Very young kittens, up to 2 months old, will look like small puffs of fur. A kitty that is about half the size of an adult cat of the same sex and breed may be around 4 to 6 months old. One that is nearly the size of an adult is between 8 and 12 months of age.
Weigh the kittens using a baby, pet or kitchen scale, depending on what you have available. At birth, kittens weigh between 3 and 4 ounces at birth. They will typically gain between 1/4 and 1/2 ounce each day, according to the American Society for the Prevention of Cruelty to Animals. By 2 weeks old, they'll usually be double their birth weight and by 8 weeks old, they'll likely be between 1 1/2 pounds to 2 pounds, according to Alley Cat Allies.
Watch the kittens for signs of sexual maturity. A kitten reaches puberty at around 6 months of age.
Items you will need
- Baby, pet or kitchen scale
- Your vet give you a better idea of your little ones' ages, along with recommendations for their care.
- Kittens less than 4 weeks old need to be bottle fed and manually stimulated to go to the bathroom.
- Very young kittens, less than 3 weeks old, need a warm environment to survive as they can't regulate their body temperature.
- Never bottle feed a chilled kitten as this can be fatal.
- Petfinder: Guide for Determining Kitten Age
- Alley Cat Allies: Kitten Progression: 1 day -- 10 weeks
- Guide to Rescued Cats: Orphaned Kittens
- The Humane Society Veterinary Medical Association Rural Area Veterinary Services: How to Determine a Cat’s or Dog’s Age
- Hartz: Determining the Age of Your Orphan Kitten
- VetInfo: Determining Kitten Age
- PetPlace: How Old is This Kitten?
- American Society for the Prevention of Cruelty to Animals: Newborn Kitten Care
- kitten image by Annika from Fotolia.com