Tools for the field
Quick calculators for vets and farmers — no sign-up needed.
General reference information: it does not replace the judgement of a veterinarian, agronomist or animal scientist. Doses and withdrawal times must be confirmed against the product's official label and your country's regulation before treating, slaughtering or selling.
Cattle (beef & dairy)
12 tools
Agronomic reference values, not a personalized technical recommendation. Confirm with a soil test, the product label, and a local agronomist/extension service.
Gestation and estimated due date
General reference — actual length varies by breed and individual. Check with your vet.
Estimated due date: —
How this was calculated
expected date = breeding date + gestation days for the species
See source
- https://animalrangeextension.montana.edu/beef/rancher_notebook_gestationtable.html
- https://www.merckvetmanual.com/multimedia/table/approximate-gestation-periods
Stocking rate (AU/ha)
1 Animal Unit (AU) = 450 kg live weight — common convention in Latin America, may vary by country.
Animal Units: — UA
Stocking rate: — UA/ha
AU equivalents (mixed herd)
- Adult cow (~450 kg): 1 UA
- Bull (~700 kg): 1.3 UA
- Steer/heifer (~320 kg): 0.7 UA
- Weaned calf (~180 kg): 0.4 UA
- Horse (~500 kg): 1.1 UA
- Sheep/goat (~50 kg): 0.15 UA
How this was calculated
AU = (number of animals × average weight kg) ÷ 450 · stocking rate = AU ÷ ha
Dry matter intake (DMI)
No single published figure; pregnant-heifer range used (~1.55-2.13%).
Intake range: — kg MS/día
NDF ceiling: — kg/día
How this was calculated
kg of DM/day = live weight (kg) × % of live weight (reference by animal class)
See source
- https://www.ams.usda.gov/sites/default/files/media/NOP-5017-3-DryMatterDemandTablesforClassesofBeefCattle.pdf
- https://extension.wvu.edu/agriculture/pasture-hay-forage/animal-nutrition/-dry-matter-intake-by-cattle
Daily gain (ADG) and days to target weight
Finishing reference: 1.1–1.8 kg/day.
ADG: — kg/día
Days to reach target weight
Estimated days: —
How this was calculated
ADG = (final weight − initial weight) ÷ days · days to target = (target weight − current weight) ÷ ADG
See source
- https://animalrangeextension.montana.edu/beef/articles/dailygain.html
- https://extension.okstate.edu/fact-sheets/an-introduction-to-finishing-beef
Adjusted 205-day weaning weight
Does not include dam-age or sex adjustment factors.
Adjusted 205-day weight: — kg
How this was calculated
205-day weight = birth weight + ((weaning weight − birth weight) ÷ age in days) × 205
See source
- https://guidelines.beefimprovement.org/index.php/Weaning_Weight
Body condition score (BCS) guide
Scale: 1–9
Target band: 5–6
Target 5-6 at calving (6 for first-calf heifers) for good rebreeding.
See source
- https://extension.okstate.edu/fact-sheets/body-condition-scoring-of-cows
Water intake
Per animal: — L/día
Herd total: — L/día
How this was calculated
L/day per animal = weight kg × L per kg for the species × climate factor × physiological factor · total = per animal × number of animals
See source
- https://www.ndsu.edu/agriculture/extension/publications/livestock-water-requirements
Animal-science reference values, not a personalized nutrition or reproductive plan. Confirm with a veterinarian/animal scientist and your herd's conditions.
General reference value; varies with region, local climate, variety/breed and management. Confirm with local extension/analysis and a professional.
Cost of gain
Kg gained: — kg
Cost per kg gained: —
How this was calculated
kg gained = (final weight − initial weight) × head · cost per kg gained = total cost ÷ kg gained
IOFC — income over feed cost
Per cow per day: —
Whole herd per day: —
How this was calculated
IOFC per cow per day = (liters × milk price) − (kg of concentrate × concentrate price) · herd = IOFC × cows in milk
Feed conversion ratio (FCR)
FCR: —
Daily gain (kg/day): —
The result follows your input: enter feed as fed and the FCR is as fed; enter it as dry matter and the FCR is on a dry matter basis.
How this was calculated
gain = final weight − initial weight · FCR = kg of feed ÷ gain · daily intake = kg of feed ÷ days · ADG = gain ÷ days
Weight from heart girth
Estimated weight: — kg
±10%: — – — kg
Morphometric estimate with a ±10 % margin: good enough to dose and decide, not to sell by. For a real weight, use the scale.
How this was calculated
weight kg = heart girth cm² × body length cm ÷ 10,838 (Schaeffer formula, metric version)
Date to reach target weight
Days to target: —
Projected date: —
Taken from your animal's real weighings. Without two weighings there is no projection: an animal's curve is not guessed.
How this was calculated
kg remaining = target weight − current weight · days = kg remaining ÷ ADG (rounded up) · date = start date + days