The entry of animal weights and weight gain is preferred as it will more accurately reflect what is happening on-farm in terms of maintenance and production requirements from pasture metabolisable energy, and any associated nutrient losses.
1. If mature weight or weight gain (start and end weights) are known, enter these weights in preference to age at start.
2. If only the mature weight is known, enter this with age at start (this will provide you with a more accurate growth curve compared with age at start only).
3. If mature weight is not known, enter age at start only.
Mature weight
For mixed aged animals, the mature weight is the average mob weight throughout the year (excluding conceptus* if applicable). Mature weight will differ between breeds and classes during different times of the year. If weight is entered it must be fairly accurate and auditable to ensure that the resultant nutrient budget is accurate.
*Conceptus is the embryo, chorionic sac, placenta, and foetal membranes in the uterus
For growing (replacements) or trading animals the mature weight is the weight when fully grown, or weight at sale or slaughter.
1. Enter the mature weight if known.
2. If the mature weight is not known leave the data entry pane blank – this will assign a national average weight based on the breed and class.
For mixed aged animals, the average mob weight is important as this affects maintenance requirements. For growing or trading animals requirements for weight gain is important and mature weight sets the shape of the growth curve.
Start and end live weight
This setting determines live weight gain that in turn affects the flow of nutrients. Greater weight gain will require more metabolisable energy uptake and result in greater N cycling. This will impact on N leaching. If weights are entered they have to be correct to ensure that the resultant nutrient budget is accurate.
1. Enter live weight at the start (for the month when the mob first appears on the stock reconciliation), and end live weight (for the month when the mob ends on the stock reconciliation (are sold) or at the end of the year in June). End live weights (or carcass weight) for mobs sold to the works are usually available on the sales docket (kill sheet).
2. If end live-weight is known but not the start weight, then enter both age at start and liveweight at end. If start weight is known but not the end live-weight, then enter both age at start and start weight.
3. If the weights are unknown or unreliable enter age at start only (see below).
Carcass weight
If the end weight is not known, carcass weight may be entered (only for some stock classes).
This is not relevant to breeding mobs and replacements. It is only relevant to trading stock. This is only visible when Fate = sold to works.