Use this estimate when the species, measurement method, body-size range, and units match the relationship implemented by the tool. It is most useful for screening, normalization, or comparing repeated measurements made under the same protocol.

Brain mass

Brain mass in grams; must be greater than zero.

Body mass

Body mass in kilograms; must be greater than zero.

The implementation follows this calculation rule: Compute the gross brain-body mass ratio as brain mass in grams divided by body mass in kilograms.^[1]

Brain-body ratio

Brain mass in grams per kilogram of body mass.

Allometric and livestock equations are empirical relationships, not direct measurements. Breed, age, sex, condition, hydration, posture, and the population used to fit the coefficients can produce systematic error. Ratios and percentages become unstable when their denominator is small, uncertain, or defined differently between samples.

Prefer a calibrated scale or direct laboratory measurement when available. For longitudinal work, pair the estimate with condition score, age, and repeated measurements collected by the same operator.

• Brain Allometry Slope

  Predict brain mass from body mass with the allometric power law predictedBrainMassG = 10^(intercept + slope x log10(bodyMassG)); defaults use intercept -1.0 g and slope 0.75 for the vertebrate brain-body scaling line.

• Dairy BCS Ratio Mapping

  Map a precomputed body-condition ratio onto a one-to-five score with round(ratio times five), clamped to the scale. This is a heuristic mapping, not a substitute for visual and palpation scoring.

• Body Length Weight

  Estimate cattle weight in kilograms from body length and chest girth with the same-family length formula.