Animal enterprises describe the animals that are on the farm and their production (milk and/or weight gain). For dairy enterprises overall annual milk production is entered. Animals are set up in mobs of “like” animals using events that add or remove animals from the mob during the year.
The following diagram depicts what parts of the model the pasture information entered in OverseerFM impacts. For a full interactive view of the scientific model in its entirety please click here
Animals is a key driver of the model for animal systems. An estimate of the energy requirements for each mob is calculated based on production (live weight gain and/or milk produced). The energy requirements are totaled by enterprise and mob and this drives the amount eaten, and therefore the nutrient intake of the animals. This drives where enterprises are located and the nutrients deposited as urine and dung each month.
Approximation of enterprise and mobs is enough.
Using RSU or peak cow numbers is not as accurate as entering mobs of animals.
A detailed stock reconciliation is not required. For farm systems which have multiple smaller movement events (those with few animals) these can be rolled up into a single event with a date that allocates the average for the month. As a maximum we advise only ever entering one movement per week which might reconcile a number of small movements over the seven days.
Mobs should contain similar animals. They can have different removal weights but must have a similar start weight.
Enter weights if significantly different to defaults and are known.
The information entered as mobs is rolled into total energy requirements by month and should represent a typical year for the farm. Therefore, accounting for every single animal and breaking it down into very detailed mobs is not necessary, rather you should provide an approximation of the overall production of each enterprise on the farm.
Each mob should describe animals of a similar class and weight gain because this determines the metabolic energy requirements of the animals. If animals are introduced into a mob part way through the year, then they should be of a similar weight/age of the existing animals in that mob.
While animals must start with a similar age/weight, animals can be removed from a mob at different weights at different times, the system will break those out into their own mobs for the purpose of modelling weight gain.
The events are used to calculate a single average number of animals for each month based on the number of animals and date of the event. This number is multiplied by the energy requirements of a single animal to determine the energy requirements of the mob for that month.
For example, if 5 animals are added on the 10th and 20 on the 20th of a month with 30 days, 5 are on the farm for 20 days and 20 are on the farm for 10 days. This results in 10 animals being added for that month. Smaller events (where the animal weights are similar) can be rolled up into a single event or a larger event if it makes it easier to enter/manage the data entry.
Animal numbers may also be entered by RSU or peak cow numbers (dairy only). The model uses that to estimate energy requirements and extrapolates it across the months of the year based on a typical enterprise of that type. This is generally not as accurate as entering mobs of animals by month but may be appropriate when just trying to provide a quick, overall view of the farm.