Practical uses of EID
Using electronic NLIS data for sheep and goat management
Current users of the NLIS technology have made practical suggestions on how to can analyse and use the electronic National Livestock Identification System (NLIS) data that you collect and store for your sheep and goats.
Individual identification allows you to:
- manage sheep and goats as individuals
- identify the better performers
- manage those not doing so well.
When Agriculture Victoria ran producer workshops on electronic NLIS (sheep and goats) across the state earlier this year, the bigger-picture stories of the advantages of the technology for on-farm use were discussed.
These ideas have come from people already using the technology and data to improve decisions and management on-farm.
Hannah Marriott described to the attendees at the recent BESTWOOL/BESTLAMB conference how she starts by requesting a bucket file when she orders her electronic NLIS tags.
She then manipulates the associated Excel datasheet to attach what she calls 'life data' to the lamb's identifier when tags are applied at marking, by recording which tags go with their dam information:
- age of dam
- breed of dam (if you have multiple breeds)
- birth status (twin, single)
- their lambing paddock and date
- sire or sire group
- breed of sire
- wool class of ewe (if grouped that way)
- marking date
- marking treatments.
If their weight is measured out of the cradle, then that can be recorded too.
Monitoring growth rates
At weaning, another weight is recorded and the lambs already have a growth rate on record. Hannah uses this to:
- plan sale dates of her prime lambs
- make appropriate paddock allocations
- book tentative slaughter dates with her processor.
At Murnong Farms, lamb growth rate is being matched with paddock data to potentially identify which paddocks the lambs grow best in and which paddocks are less productive.
Monitoring growth rates also allows you to identify the slow growers, who may be best managed by selling as stores, rather than retaining for too long trying to finish them.
Joining weights for ewe lambs
Hannah also provided an example that she had come across in her Nuffield Scholarship study in New Zealand. A producer found that the life data provided the clue that ewe lambs born from ewe lambs didn't need to be as heavy at their first mating as those born from adult ewes. This may or may not apply on your farm — monitor them to find out.
Analysing pregnancy scanning results
David de Pury had a slightly disappointing pregnancy scanning result in his prime lamb flock, so analysed the data by looking at paddock, ewe age, mob and anything else he could think of.
It turns out that the poor-performing ewes were those mated to terminal sires, rather than the maternal-type sires. It wasn't the rams' fault, they had been mated with the ewes that were the poor performers from last year — the ones that had only reared one lamb.
David is now considering whether it is worthwhile keeping these ewes at all, given the impact on the future fertility of his ewe flock.
Drafting large mobs into management groups
David needed his data records to perform the analysis, because his ewes are run in large mobs after mating, then divided near lambing into their appropriate lambing groups based on factors such as scanning percentage and body condition.
At Avington Merino Stud, the entire flock of 4000 ewes is run as a single mob during spring as they are rotated about the farm to control the spring flush of growth. Because this is a stud, many of these ewes will be marked for single sire matings. An auto drafter run by their electronic NLIS (sheep) identity makes light work of sorting these ewes into many small mobs for mating.
Steve Harrison noticed that within a year of starting to use electronic NLIS (sheep) in his stud that he was only spending half as long in the yards sorting his rams as he used to. The grunt work is now done in his office as he manipulates their data file.
Identifying top performers
Previous issues of Sheep Notes have described how Pedigree Matchmaker®, combined with records of weaning weights of lambs, can identify which ewes are rearing the most kilograms of lamb. In prime lamb flocks, ewes that successfully rear triplets usually outperform any ewe rearing a singleton lamb.
At Avington Merinos, use of OFFM (On Farm Fibre Measurement) in-shed testing at shearing time allows their classer to sort fleeces into lines of very tight specifications. Having recorded fleece weight, and which fleeces go into which line, they can easily calculate the value of every ewe's wool cut once it is sold — identifying the most valuable ewes in their stud.
Which sheep to quit as drought approaches
Both of the above examples also provide opportunity to identify the poorest performing sheep in the flock, earmarking them as the first to be culled as a drought looms. The slow-growing lambs can be sold early as stores, freeing up valuable fodder for the sheep you retain.
Which sheep to drench
Targeted selective treatment is one of the ways in which selection for anthelmintic resistance can be reduced. This is by leaving a portion of the mob undrenched, the size of refugia for parasites that have not been exposed to the anthelmintic is increased. Ian Carmichael of Primary Industries and Regions SA says the best way to identify which sheep to leave undrenched is to monitor weight change — the ones gaining the most weight can be left undrenched.
To do this, weigh a portion of the mob when yarded (say, 50 sheep) and analyse the weight change of the sample to work out an appropriate level of weight gain at which to stop drenching.
Then enter this change level into the dataset to allow you to work out which ones of the mob to draft off to leave undrenched. (There were some autodosing drench guns on display at the BESTWOOL/BESTLAMB conference that supply the exact dose for a sheep's given body weight as measured on the scales.)
What data to collect
Nathan Scott of Achieve Ag advises producers not to record data just for the sake of recording it. Hannah Marriott advised her audience to not bother collecting data the next year that you didn't use the year before.
Make note of what you wished you had recorded to make sure you begin collecting it in future.
The opportunities are limitless, and these are just some ideas to get you started.
Hannah also cautioned that data analysis takes time. It may be better to pay someone to do the analysis for you.