Under Breeding → Fertility you find your herd's key figures. The same page is reachable via the tab bar Reports → Fertility, where the other analyses live as well, see Reports & Analytics. It follows two rules that set it apart from many other analyses: every figure names its sample, and where the sample is too small, no number is shown.

If your farm keeps several species, the chips at the top choose which one you see.

Fertility figures with sample size and reference bands

Why a figure is sometimes missing

An average over two animals is not a key figure, it is chance. So Herdy only shows a value from a minimum count:

Distributions (age at first calving, calving interval, offspring per birth) from 5 values
Rates (pregnancy rate, stillbirth rate) from 10 animals

Below that it reads "Not enough data yet (3 of 10)" — so you can see how far off it is. That is more honest than a number you cannot trust.

Implausible values

A "calving interval" of 30 days is not biology, it is a duplicated birth record. Such values do not enter the average — but they do not vanish silently either: they appear as "n implausible" next to the figure. That is your cue to check the records.

The two blocks

Straight from the TVD

These numbers are available without any data entry of your own, because they come from the TVD data — for cattle the import supplies birth and calving dates:

Age at first calving — how old your cows were at their first calving
No calving for over 400 days — a list, not a number. A click takes you to the animal.

Worth knowing: the calving interval is not in this block. The TVD supplies the first and last calving, but not how many there were in between — no interval can be derived from that. This figure fills up once you have recorded two births of the same animal.

From your own records

Grows with every recorded mating, check and birth. At the top you see the coverage, e.g. "19 of 26 dams have a recorded mating" — so you can judge how much of your herd the figures rest on.

Calving / lambing interval
Pregnancy rate
Offspring per birth
Stillbirth rate
Pregnancy rate per sire

Pregnancy rate per sire

This figure deserves particular attention. According to BGK/SSPR only 70--75 % of sires are genuinely ready at the start of the season, and one sire carries up to 50 ewes. An empty sire therefore costs a whole season — and nothing else in the herd data reveals him.

If something like "4/10" appears instead of a percentage, it means: animals are still missing for a reliable rate.

Reference values

Reference bands with their source sit next to the figures. If your value falls outside, it is highlighted.

Figure	Species	Reference	Source
Age at first calving	Cattle	24--30 months	Mutterkuh Schweiz
Age at first lambing	Sheep	15--18 months	SSZV
Age at first kidding	Goat	12--15 months	FiBL
Calving interval	Cattle	up to 400 days	Swissgenetics
Pregnancy rate	Sheep, goat	from 95 %	BGK/SSPR
Offspring per birth	Sheep, goat	1.5--1.8	BGK/SSPR

Where no documented Swiss reference exists, Herdy deliberately shows none — a guessed number would be worse than nothing.

Gestation lengths on file

Herdy calculates the due date from these values. For cattle it does so per breed, because the differences run to nine days — a blanket figure would be regularly wrong on a Limousin farm.

Cattle, by breed

Breed	Gestation
Jersey	281 days
Angus	281 days
Holstein	282 days
Red Holstein	284 days
Eringer	284 days
Swiss Fleckvieh	286 days
Braunvieh / Brown Swiss	290 days
Original Braunvieh	290 days
Limousin	290 days
Simmental / Fleckvieh	290 days
All other breeds	285 days

Other species

Species	Gestation
Sheep	147 days
Goat	150 days
Pig	115 days

For pigs that matches the rule of thumb "3 months, 3 weeks, 3 days".

Your own value per mating

If an animal deviates regularly, you can enter your own gestation length in the mating form under Advanced options (100 to 320 days). That value takes precedence over breed and species.

Cycle parameters per species

These values drive when Herdy proposes heat and check dates. They can be adjusted per species under Breeding → Heats, using the gear icon at the top right. See Heat monitoring.

Parameter	Cattle	Sheep	Goat	Pig
Cycle length	21 days	17 days	20 days	21 days
Return-heat checks	2 cycles	2 cycles	2 cycles	2 cycles
Pregnancy check after	35 days	40 days	40 days	—
Re-check after an unclear result	14 days	14 days	14 days	14 days
Heat check after birth	21 days	—	—	—
Breeding-age watch	15 months	10 months	7 months	7 months
Breeding season	all year	Sep--Dec	Sep--Dec	all year

The values come from Swiss association sources: Mutterkuh Schweiz and Swissgenetics for cattle, BGK/SSPR and SSZV for sheep and goats, SUISAG for pigs, FiBL for goats.

Pigs: no pregnancy-check date is held for pigs yet — the return-heat check already covers the early window. We are clarifying with the swine health service whether an additional date is useful, and will only add it with a documented source.