A nursing queen's weight is the cheapest early-warning system in a litter. It moves 24-48 hours before behaviour does, it is read in grams on a kitchen scale, and it costs 90 seconds a day. Weigh her once daily at the same time, treat 3 consecutive days of decline as a line that has been crossed rather than a bad week, and know the 2 findings that mean a vet today.
Why daily, and why before the first feed
A queen giving milk to 4 kittens can lose 60-120 g of body weight a day in water and fat, so single readings swing. That is exactly why the trend matters more than the number: one 60 g drop on a 4.2 kg queen is 1.4% and means nothing, while 3 days of 40 g drops add up to 120 g and 2.9% and mean something.
Weigh at the same point in the day, before the first feed, after she has urinated if she cooperates. A full stomach adds 30-50 g and a full bladder another 20-40 g, which is enough to erase a real signal. Use 1 scale, keep it in the same place, put down the same towel, and record grams rather than kilograms.
What normal looks like in the first 5 days
Most queens lose 5-8% of their pre-birth weight in the first 48 hours: 210-340 g on a 4.2 kg queen. That loss is expected and should stop by day 3. From day 4 or 5 the line should flatten, then rise slowly, at 20-40 g a week while the litter is small and 0-20 g a week once the kittens are taking everything she produces.
A queen who is back at her pre-birth weight by day 10 is doing well. A queen still 300 g below it on day 14 is not, even if she looks bright, eats and nurses.
The 3-day line, defined
Three consecutive weigh-ins, each lower than the one before, with a total fall of 3% or more of body weight, is the line. On a 4.2 kg queen that is 126 g: 4020 g, 3975 g, 3955 g across 3 mornings is 65 g and stays inside normal; 4020 g, 3960 g, 3900 g is 120 g and is close to the line; 4020 g, 3950 g, 3880 g over 3 days is over the line and gets a call that morning.
Two rules keep the line honest. Never compare a morning weight with an evening weight, and never average 3 days to soften a fall. If a single day drops more than 2% (84 g at 4.2 kg), reweigh the same evening to rule out a scale error, then treat it as day 1 of a possible 3-day slide.
The litter is the second half of the reading
Kittens gain 10-14 g a day in the first week and should double their birth weight by day 8-10. Weigh the whole litter together once a day, in a lined basket, and each kitten individually every 2 days. Group weight is fast and catches a general milk problem; individual weight catches the one kitten being pushed off.
A kitten that is below its birth weight at 48 hours, or that loses weight 2 days running, is a same-day call whatever the queen's own numbers say. Group gain of under 30 g a day for a litter of 4 is a supply question rather than a kitten question.
Appetite and meal counts
A nursing queen eats 1.5-2.5 times her maintenance intake. At 4.2 kg and roughly 60 kcal per kg, maintenance is about 250 kcal, so expect 380-620 kcal a day, split into 4-6 meals, with free access to water at 60-100 ml per kg. Food left in the bowl at the next meal is data, not fussiness.
Record grams offered and grams left, not just a tick. A queen eating 90% of 4 meals a day is fine; a queen eating 50% of 2 meals is not, even when the daily total looks similar.
Nursing frequency, and what a change means
Count nursing bouts inside 3 fixed 30-minute windows rather than all day. Week 1 usually runs 8-12 bouts a day, week 3 drops to 6-8, and by week 6 it is 4-6 as kittens start on solids. A sudden drop to 2-3 bouts with crying kittens is a supply or comfort problem; a queen who leaves the box for more than 30 minutes at a stretch in week 1 is worth watching.
The 2 vet triggers
- The 3-day line is crossed, or a single weigh-in falls more than 2% below the day before. Call within 24 hours with the log, the temperatures and the litter weights; a queen losing weight while nursing is the classic picture of a supply problem that has not yet become visible.
- Fever or food refusal. A rectal temperature above 39.4 C, or 12 hours without eating, or a mammary gland that is hot, hard and painful to touch, is a same-day visit. Below 37.5 C is equally urgent and easier to miss with an ear thermometer, which reads 0.5-1 C low.
Anything in between - a queen who is 1.5% down, eating 70% and slightly quiet - is a 24-hour recheck of weight and temperature at home, not a wait-and-see week.
The one-page record
Five fields, one line a day, kept next to the scale. The table below is a normal first 2 weeks for a 4.2 kg queen with 4 kittens.
| Day | Queen (g) | Litter (g) | Bouts | Food (g) |
|---|---|---|---|---|
| 1 | 4020 | 470 | 10 | 210 |
| 2 | 3975 | 515 | 11 | 235 |
| 3 | 3960 | 560 | 10 | 250 |
| 4 | 3990 | 610 | 9 | 270 |
| 7 | 4030 | 760 | 8 | 305 |
| 10 | 4080 | 900 | 8 | 320 |
| 14 | 4110 | 1010 | 7 | 340 |
The shape matters more than the digits: a dip of 60 g over 2 days, a flat day, then a slow climb of 20-30 g a week. Copy the shape, not the numbers.
What to take to the visit
Bring the sheet, the last 3 temperatures, the litter weights, the number of kittens nursing per bout, and the exact date of birth. A clinic can act on 7 days of grams in 2 minutes; without them the visit starts with a guess. Ask for the cost of bloodwork and imaging before it is run; the cost tables list routine figures.
Two related checks are worth reading before the litter arrives: the pregnancy weight curve that gives you the pre-birth baseline, and the post-whelp recovery checklist for the first 72 hours.
Your first 7 days
- Weigh the queen once a day, before the first feed, and write grams.
- Weigh the litter daily as a group and each kitten every 2 days.
- Record grams offered and left at every meal, 4-6 meals a day.
- Count bouts in 3 fixed 30-minute windows and note the number.
- Take a rectal temperature once a day for the first 3 days, then on any day the weight falls.
- Draw the 3-day line on the sheet so a slide is visible without arithmetic.
Frequently asked
How much weight can a nursing queen lose before it is a problem?
A 5 to 8 percent drop in the first 48 hours is normal, which is 210 to 340 g on a 4.2 kg queen, and it should stop by day 3. After that the line flattens and then rises 20 to 40 g a week. The line to act on is 3 consecutive weigh-ins each lower than the last with a total fall of 3 percent or more, or any single day down more than 2 percent.
Should the kittens be weighed as a group or one by one?
Both, at different speeds. Weigh the whole litter in a lined basket once a day to catch a general milk problem, and each kitten individually every 2 days to catch the one being pushed off a teat. Kittens gain 10 to 14 g a day in week one and should double their birth weight by day 8 to 10. A kitten under its birth weight at 48 hours needs a same-day call.
What temperature means the queen needs a vet today?
A rectal reading above 39.4 C, or below 37.5 C, with 12 hours without food, or a mammary gland that is hot, hard and painful. Go the same day rather than watching for another 24 hours. Ear thermometers read 0.5 to 1 C low in cats, so a 38.6 C ear reading can hide a genuine fever and a rectal check is worth the two minutes.