Colostrum Window: 24 Hours and 3 Records per Kitten

The useful part of colostrum is not the fluid, it is the 24 hours. A newborn kitten takes up large antibody molecules through the gut wall for roughly the first 16-24 hours of life, and that capacity falls steeply after the first 6-8. Past 24 hours the gut has closed and the same milk delivers nutrition instead of immunity. That single fact decides what gets written down: 3 records, all of them inside day 1.

What follows covers the window and the paperwork. It is not an argument for breeding, and it does not cover delivery handling, which belongs with a vet and with whoever is responsible for the queen.

The window is 24 hours, not 72

Vets describe it as a curve rather than a switch. Uptake in the first 2 hours is at its highest, roughly halves by 6-8 hours, and is close to 0 somewhere between 16 and 24. Two consequences follow. The first suckle matters more than the total volume of day 1, and a kitten that suckles at 3 hours is in a different category from one that first suckles at 20.

The curve also explains why a bottle cannot replace it. Feeding volume can be matched within an hour; the open gut cannot be reopened, so the record of when the first suckle happened is the only evidence that the window was used at all.

What the first 24 hours look like on paper

Window	Uptake	Record	Working threshold
0-2 h	highest, about half the total	minutes to first suckle	under 60 min is unremarkable
2-6 h	high, then falling	weight in g, and minutes of sucking	birth 90-120 g
6-12 h	under a third of peak	weight in g	loss under 5% of birth weight
12-18 h	low	temperature in C	35.5-37.5 C
18-24 h	closed or nearly	24-hour weight and daily gain	10-15 g a day from day 2

Record 1: minutes to the first suckle

Write clock time and minutes from birth, not a tick in a box. Three numbers earn the row: minutes to first teat contact, minutes of active sucking in that first session, and total minutes of sucking inside the first 2 hours. A kitten at 15 minutes to contact and 20 minutes of sucking has done most of its immunological work by the end of hour 1. A kitten at 3 hours is late enough that the vet should hear about it the same morning.

Write the queen's side too: whether she was still cleaning the kitten at 10 minutes, and whether the kitten was on a teat or merely near one. Contact and intake are 2 different events and only 1 of them counts.

Record 2: weight at 0, 12 and 24 hours

Weigh on a 1 g scale, the same scale every time, kitten in the same towel so the towel does not move the number. Birth weight sits at 90-120 g for most breeds and 80-140 g across the full range. A loss of 5-10% in the first 24 hours is common and tolerated; over 10% is the number that turns a record into a phone call. From day 2 the expected gain is 10-15 g a day, which makes the 24-hour weight the most useful single row on the sheet.

Three readings, 3 lines: 0 h, 12 h, 24 h, each with time and scale. If you weigh only once, make it 24 hours, because that is the number a vet will ask for first and the one that cannot be reconstructed later.

Record 3: temperature, 3 readings in 24 hours

Newborns cannot regulate heat and sit at 35.5-37.5 C. Read at 0, 12 and 24 hours and write nest temperature beside it: 28-30 C for week 1, 50-60% relative humidity. A kitten at 34 C is losing heat faster than it produces it, and that is a vet call rather than a blanket adjustment. Note the reading method in the header so 2 people do not mix surface and core numbers in 1 column.

Collection records, when a vet asks for them

Collection and storage follow the vet's protocol; the cattery's job is the log. Five fields: date and clock time, single-collection volume in ml, container label, storage temperature (below -18 C for frozen) and the date frozen. Add thaw date and discard date when a container is opened. A label without a date is not a record, and 2 containers without labels are a wasted freezer.

The 4 numbers that mean call the vet

No suckle by 3 hours. Weight loss over 10% at 24 hours. Any temperature under 35 C. No gain in 24 hours after day 2. Add a fifth when the litter is large: 7 kittens or more, with a 30 g spread between heaviest and lightest at 24 hours. These are thresholds for a call, not a diagnosis, and the sheet you hand over is worth more than the description you give from memory.

The handling side of day 1, including how much contact a kitten tolerates in the first 2 weeks, is covered in the kitten handling window. Whether a line carries a trait that could affect a litter is a question for testing done long before, not during, the first 24 hours: the genetic test list covers the panels most often requested.

Do this in the first hour

• Start the clock at birth; write the minute of first teat contact.
• Weigh the kitten once, on a 1 g scale, and write the scale's ID.
• Write nest temperature and humidity in the page header.
• Open 3 rows: 0 h, 12 h, 24 h, with a blank for gain.
• Photograph the sheet at 24 hours, because paper gets wet in a nursery.

Three records, 1 page, 24 hours. The window closes on its own schedule, and the only part you control is whether the numbers exist afterwards. If the litter came from a breed whose weight band you are unsure of, the breed quiz gives a 2-3 candidate shortlist to compare against.

Frequently asked

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• Kitten Handling Window: Day 3 to 16, 3 by 5 Minutes
• Cattery Disinfectant: 3 Classes, 1:32, 10 Minutes
• Cattery Hygiene: 1:32 Bleach, 30-Second Hands
• Kitten Contract Clauses: Deposit, Health, Desexing
• Cat Infertility Workup: 6 Steps After 12 Months
• Kitten Sex ID: Reading the Gap at 0 to 8 Weeks