Development in the first six weeks of a kitten’s life

The first six weeks of a kitten’s life are critical to its development. They grow and develop rapidly, but they are vulnerable to many threats. Now outside the womb, kittens need warmth, food, and protection from infectious diseases and parasites such as fleas.

Kittens will likely never grow again at the astonishing rate they have accomplished during this time, and seeing their development change every week is an incredible experience. Get to know their first week and move on from there.

Week 1: Small Food Processing Plant

Newborn kittens weigh just a few ounces and fit easily in the palm of your hand. Its umbilical cord will fall off in two or three days, but its eyes and ear canals will not open.

Kittens are helpless at this age, but mother cats instinctively know their needs. She feeds them, keeps them close for warmth, and bathes them with her rough tongue, which also stimulates their digestion and helps them urinate and defecate. Female cats are very protective of their little ones and will move them to another location if humans invade the nest too much.

If the mother is vaccinated or has natural immunity, kittens will gain the same immunity through colostrum within the first 24 to 48 hours, and this immunity will last until they are old enough to be vaccinated against kittens.

Newborn babies weigh an average of 3.5 ounces at birth and may double their weight by the end of the first week. It’s a good idea to weigh them and monitor their weight to see if they’re getting enough nutrients. At this point, they are just small food processing plants, and their only activities are nursing, sleeping, and excreting waste. There is little social interaction at this age, other than fighting over their favorite nipple, which they suck while kneading with their tiny paws.

A rule of thumb for feeding kittens is 8 cc of formula per ounce of body weight per day. You will gradually increase the amount of formula with each feeding and decrease the number of feedings. Cubic centimeter (cc) is the same as milliliter (ml). One ounce equals 30 milliliters or 30 milliliters.

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Week 2: Growth and Development

Your kitten is continuing to grow at an incredible rate, gaining at least 10 grams per day. A mother cat should be fed high-quality canned kitten food to help replenish the nutrients she loses through breastfeeding. Later, kittens will be introduced to the same food.

Its eyes will begin to open and will be fully opened between 9 and 14 days of age.All kittens have blue eyes and will last for several weeks. Their vision will be blurry at first, and their pupils do not easily dilate and constrict, so they should be kept away from bright light.

Week 3: Consciousness is developing

The ear canal will be fully opened and their hearing is still developing. However, kittens may be startled by loud noises. By this age, their ears may be fully erected.

Their eye color may begin to change, from the blue common to all kittens to the adult color. Their sense of smell will be well developed.Kittens can now excrete voluntarily because their digestive systems are developing. Female cats will continue to clean them until they learn grooming skills.

Don’t be surprised to hear kittens start purring at such a young age. Now that the baby teeth will start to appear, the mother cat will start thinking about weaning.

Week 4: Standing and Shaking

Kittens will start standing and trying to walk sometime between weeks three and four, although their first movements will be quite wobbly.Their bodies are out of proportion to their final adult state. The small tails are short and “stick-like”, and their head is disproportionate to the body and legs. However, that all changes as they get “sea legs” and start walking around.

Don’t be surprised to see kittens fleeing from nesting areas in their quest to expand their horizons. They will also interact more with their littermates and even form “alliances,” which may or may not be based on gender.

Kittens will continue to breastfeed regularly. It is important to continue feeding the mother a quality food as long as she is nursing the kitten.

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Week 5: Begin the weaning process

The kittens will now move around freely and start playing with their siblings.They will develop a new sense of independence, although they may not be far from their mother or their littermates. This will be a good time for them to interact with humans.

At this point the kitten can be introduced to canned food. Choose a quality brand of cat food with a designated meat source as the first ingredient (chicken is fine). Ideally, they should get the same kitten food as the mother cat, as kittens adapt quickly and eat their mother’s food. Use shallow plates and expect their first experience to be messy.

Although mother cats will try to wean their kittens, they still need nursing experience to meet their nursing needs – at least until they are 8 or 10 weeks old, they will be weaned gradually.

Kittens can now learn litter box basics too. They need a smaller, self-contained box, one that’s easy to get in and out of, with just an inch or two of litter. Shallow plastic storage boxes or shoebox lids may be suitable for beginners. Just as human babies experiment by tasting everything, so do kittens. Use natural waste, such as those made from corncob, paper or wood chips, to prevent them from ingesting harmful substances – never caking clay.

Week 6: Socialization in full swing

Social skills continue and there is no doubt that these are lively, active kittens who will soon grow into adult cats. They can run, pounce, and jump, endlessly entertaining themselves and human observers. Just like they can fall asleep quickly (growing up is hard work), so be careful not to tire them out.

Kittens will follow the mother cat to socialize with humans. If she is on good terms with the humans in her life, so will her kittens. However, if kittens are not used to manual handling by six weeks, training them later can be a long and slow process, and such cats may never become “lap cats.”

Illustration: Katherine Song. © The Spruce 2018


Kittens at this age should know that hands are not for play – they are for scratching, petting and feeding. One of the best “toys” to teach this lesson is a plastic straw. You can drag it across the floor and watch the kitten chase it, then wiggle it a little so that it pounces on it and “catches” it. Before settling down to bite it, the baby may proudly swagger with its prize. Make sure to supervise your kitty when using the straw, as you don’t want them ingesting plastic.

almost time to go home

Well-socialized and fully weaned kittens may be ready for their new home in a few weeks. If you’ve been waiting for your kitten to be old enough to adopt, you’re probably going to be very excited at this point.

Be patient, though. Remember that “all good things are worth the wait” and ideally kittens won’t be adopted until they are 7 to 9 weeks old.

If you suspect your pet is sick, call your veterinarian right away. For health-related questions, be sure to consult your veterinarian, as they have examined your pet, know your pet’s health history, and can provide the best advice for your pet.