Breeding statistics report

Includes conception rate, birth rate and weaning rate.

The success of breeding from conception to weaning of offspring is an important measure of herd performance and the efficiency of the farming system, especially for extensive beef farming systems.

The individual-based ruminant model used by CLEM tracks the status of every individual and knows the full breeding state of the herd at any time. This information is provided for reporting by a ConceptionStateChanged event that returns an entry every time the conception status of a female changes. The following status changes are reported.

  • Not ready indicates that the female was less than age at first mating or within the specified period after last birth before next conception
  • Not available for mating in this time step in that she was pregnant
  • Not mated shows that the female was not mated due to either location restricting bulls or insufficient bulls to service the herd
  • Unsuccessful indicates that conception was attempted but the female did not conceive. This is either due to being below condition (see Ruminant conception by condition) or not within conception probability (see Ruminant conception curve)
  • Conceived shows successful conception by female in this time step
  • Failed represents a prenatal or at birth mortality (see Breed properties). This is reported only if all individuals from a multiple birth die before birth.
  • Birth states that a birth resulted from the specified conception date (NOTE: this represents actual individual births for multiple births and not the single birth event resulting in multiple individuals)
  • Weaned states that a weaning occurred form the specified conception date. This is reported for each individual weaned.

All entries relate to a specific breeding date (conception date) allowing the number of births and weaned individuals from the conceptions on a given date to be calculated. This can further be summarised to give annual statistics, especially for controlled mating happening once per year.

There is an additional change in conception status recorded if a female was missed on a breeding occasion (not enough males for mating in uncontrolled) or it was an unsuccessful mating. These two values along with count of conceptions allow you to calculate the total number of breeding females present and total number mated in any month.

This dataset can also be analysed to give more details such as conception rate by age or weight, or even develop full breeding history of each female to determine average months between conceptions, births per year over the whole simulation.

You will need to add an APSIM Report component to your simulation. In future we may develop an automated version of this report.

This example assumes the Ruminant Herd is named "Ruminants" and we are interested in the Ruminant Type named "B indicus".

Once this report is added you will need to assign the following settings.

[Clock].Today as Date

[Resources].Ruminants.B indicus.LastConceptionStatus.ConceptionDate as ConceiveDate

[Resources].Ruminants.B indicus.LastConceptionStatus.Status as Status

[Resources].Ruminants.B indicus.LastConceptionStatus.Female.ID as ID

[Resources].Ruminants.B indicus.LastConceptionStatus.Female.Age as Age

[Resources].Ruminants.B indicus.LastConceptionStatus.Female.NumberOfBreedingMonths as BreedMonths

[Clock].Today provides the ability to report all conception changes on the date they occurred for exploring breeding dynamics

The entries can be simplified by using the first component in the tree with a unique name surrounded by the square brackets. [B indicus].LastConception

The last three variables are optional. These are needed if you want to perform analysis on individual females (ID, or actual conception events with yyyy/dd/ID as unique identifier), based on age at mating (Age) or based on the actual number of months the female was in the simulation and in breeding age (allows to ignore time prior to when breeders were purchased but of breeding age). This would allow the calculation of number born/weaned per female over time.

You could add additional female properties such as weight, normalised weight, weight at last conception, ProportionOfHighWeight, ProportionOfNormalisedWeight, ProportionOfSRW or any others that may be useful in your analysis.

[Resources].Ruminants.B indicus.ConceptionStatusChanged

Run your simulation and the breeding details report will be in the datastore with the same name as given to the report

This report may produce a large table when simulating large herds over extended periods, so the report can be disabled when not needed.

No conception status will be reported after the death of a breeder. This means that any weaning of suckling offspring after her death will not be reported.

The reported Births and Weaned status changes relate to each individual born (for multiple offspring conceived). This allows multiple births to be tracks and calculated.

This report will include entries prior to the start of the simulation. These will be produced for mothers of the initial suckling individuals specified as well as the pre-simulation inferred pregnancy status if required.

See also