When do kittens open their eyes?
A kitten's eyes open between seven and ten days after birth. All kittens are born with blue eyes which change colour between 8 - 12 weeks of age.
All kittens are born with their eyes fused shut, this is because certain species of animals (including cats) are what is known as altricial. This essentially means that newborn kittens are born almost immobile and completely helpless for a period of time after birth (in comparison to say a horse, who is on its feet within an hour) This makes evolutionary sense as cats are predators, who in the wild spend a lot of time stalking, chasing and hunting down their prey. This would be difficult to do in a heavily pregnant female, so a trade off is to have a shorter gestation period than other species who don't hunt for their food.
The shorter gestation period means that altricial offspring are born underdeveloped in many ways (birds are born without feathers). In kittens, their eyes are fused shut and even once they have opened, their eyesight is quite poor.
It is not uncommon for your kitten to have a bit of crustiness around the eyes when they open. Please see a veterinarian if this occurs as eye infections are common in newborn kittens and left untreated can lead to blindness. The kitten's eyesight is fully developed by five weeks of age.
Other kitten milestones:
Kittens are also born toothless. Their baby teeth come in around week three, and should have all of their baby teeth by 6-8 weeks. The adult teeth come in around 4 months of age. Kittens have 26 baby teeth and adult cats have 30.
Kittens should be wormed from two weeks of age and then every two weeks until they are 12 weeks, then every three months from then on.
Kittens start to walk around from three weeks of age, albeit shakily at first.
At six weeks old your kitten should receive his first vaccination, and again at 8 and 12 weeks.
The weaning process starts at five weeks of age. You can offer your kittens soft food at this stage.
Kittens are ready to leave their mum around 10-12 weeks of age.
Other random kitten facts:
Sometimes the mother cat (known as a queen) will chew off the whiskers of her kittens. This is normal and they will grow back.
You may notice when a kitten is nursing from his mother that he gently kneads her belly. It is believed kittens do this to help stimulate the mother's flow of milk. Some cats continue to knead soft objects well into adulthood. I have a ten-year-old Singapura cat who still kneads soft blankets.
Milk is good for kittens, they can only consume milk for the first few weeks of their life. This milk should come from their mother, or if they are orphaned a suitable milk substitute. Cow's milk is not suitable for kittens.
The average size of a litter is between 3 - 5 kittens. First-time mothers may have smaller litters of just one or two kittens.