Everyday animal mortality rate problems come down to one relationship between closing stock, number of animals sold, number of deaths from disease, number of disease cases, number of newborns and opening stock. This calculator turns those numbers into cumulative mortality, number of deaths and available stock, with the working shown so you can check the result rather than simply trust it.
What Is the Animal Mortality Rate Calculator?
The animal mortality rate calculator works out cumulative mortality, number of deaths and available stock from closing stock, number of animals sold, number of deaths from disease, number of disease cases, number of newborns and opening stock.
Biological relationships are usually approximations rather than exact laws, so the output is best treated as an estimate with a sensible range around it.
How the Animal Mortality Rate Calculation Works
The calculation applies the relationship as published, step by step, so each intermediate value can be checked against the underlying theory.
Keep the units consistent throughout. Mixing a percentage with a proportion is the single most common source of an answer that is out by a factor of a hundred.
Assumptions Worth Knowing
Any relationship used here assumes a constant rate, a representative sample, or a stable population. Real populations rarely meet those conditions for long, so treat the answer as a guide.
Where the inputs are field measurements, a single misread value can shift the result noticeably. Measure carefully and record what you used.
A Worked Example
Working through an example, with closing stock set to 10, number of animals sold set to 5, number of deaths from disease set to 2, the calculator returns number of deaths of 0, and mortality rate of 0, and cumulative mortality of 0. Substitute your own figures and the same steps produce the same kind of answer.
Frequently Asked Questions
What do I need to work out cumulative mortality?
Enter closing stock, number of animals sold, number of deaths from disease, number of disease cases, number of newborns and opening stock. The calculator then works through the relationship and reports cumulative mortality, number of deaths and available stock.
What does the animal mortality rate actually calculate?
It takes closing stock, number of animals sold, number of deaths from disease, number of disease cases, number of newborns and opening stock and converts them into cumulative mortality, number of deaths and available stock using the standard relationship for this problem. Each step is applied in turn, so every output is traceable back to the numbers you typed in.
How should I enter closing stock?
Use the value you actually have, in the unit shown next to the field. Enter every value in the same unit system. The calculator assumes the figures you supply are consistent, so it cannot correct a mistake that happens before the calculation starts.
Is the answer exact?
It is as exact as the formula and the inputs allow. The method itself is the standard one for this problem, so the only sources of error are the figures you enter and the precision you ask for.
Why does a small change in one value move the answer so much?
That happens when an output depends on a ratio, because dividing by a small number magnifies any change in it. Check the units first, then check whether the value you entered is in the range the relationship was designed for.