By Dr Clive Dalton
Identification & recording
- You cannot do worthwhile recording and breeding to improve flock performance unless all animals are identified.
- This ID must be unique so that no two animals have the same identity.
- No system of ID is ever perfect, as there are always problems with permanent tags being pulled out on fences, and temporary marks on fleeces fading or being shorn off.
A unique identity
- The best way to form a unique identity is to use an individual number along with the goat’s year of birth.
- So for example 123/05 is number 123 born in 2005. There may be other goats numbered 123, but they won’t have been born in 2005.
- The best ID method is a brass ear tag put in the kid’s ear at birth and then supplemented with a plastic tag later when the ear grows bigger and stronger. Some breeders put a brass tag in both ears to reduce the chance of lost identity.
- There is much less chance of a brass tag coming out or fading than a plastic tag. However, recent advances in plastics have greatly reduced the fading of numbers and colours in plastic tags from the intense sun radiation in New Zealand.
- So each year get your tags (both plastic and brass) to run from Number 1 to however many kids you expect to have, and add the year born on to each tag. With brass tags, get your name punched on the third side too.
- Visible plastic ear tags also have many advantages for general management such as using different colours for age groups.
Good permanent ID methods
Brass tags
- These have proved their worth over decades in New Zealand sheep.
- Which ear? Always put the brass tag in the left (nearside) ear, as this is the one held by the shearer when coming up around the neck.
- Where to put it? Punch it into the top of the ear, about a third of the way along from the head toward the tip, leaving room for the ear to grow and so the tag to remain in a readable position.
- If you put it too near the head it can grow into the skin folds, and you’ll have to fight the goat every time to read it, and the animal will remember the experience.
- Always read brass tags from left to right to avoid confusing 66 with 99.
- Keep all tagging equipment disinfected during and after use. Check for any ear infections and festering a couple of days after tagging.
- Brass tags come on sticks with a rubber band on the end, to stop them slipping off and getting out of numerical order when you drop them!
Very small plastic tags
- These are like a numbered pliable plastic band that bends around the edge of the ear when clinched together. They can be put in a kid’s ear at birth without causing it to droop and malform it, and little festering occurs if you keep your gear clean.
- These tags come in a range of colours and you cannot read these from a distance.
Medium plastic tags
- These are smaller and less expensive than the very large tags.
- Put them in the goat’s left (near) ear to help the shearers.
- They are still too heavy to put in young kids and even kid’s at weaning.
- They are easier to read than the small plastic bands, but you’ve got to be up fairly close to the goat to read them.
- They are an ideal intermediate tag, but farmers don’t like the expense and bother of replacing them so will wait till the goat is big enough for a large tag.
Large plastic tags
- These are “flag” type tags that you can easily read from a distance of 3-5 m and come in a range of bright colours.
- Put them in the doe’s left (near) ear to help the shearers.
- You can have them numbered or you can write your own numbers on with a supplied pen containing ink that doesn’t not fade. Some fading is inevitable in New Zealand’s intense sun.
- Don’t put these in kid’s ears until they are at least 5 months old as they are too heavy for the kid’s small ear and it will pull it down and permanently disfigure it. Also more festering can occur.
- Punch them in the middle of the ear about half way along avoiding the two main ligaments and the veins.
- Keep all tagging equipment disinfected during and after use. Check for any infection and festering a couple of days after tagging.
- Always put the same number on the plastic tags that is on the brass or small plastic tag, and it’s a good idea to use different colours for each year’s crop of kid’s to help sorting age groups later.
- Don’t use old plastic tags as it will only cause confusion.
- You can cut bits out of the edge of plastic tags with ear marking pliers to denote groups or ages.
- There are also plastic tags that slip through a punched hole can be used to identify age groups. These are put in the top or bottom edge of the ear and can be easily removed but they cannot be read from a distance.
Poor permanent ID methods
- Self-piercing aluminium tags were once popular but have not shown any great advantage over the brass tags which once the ear heals are generally trouble free.
- Tattoos. Here sharp pins in the shape of numbers and letters are held in special pliers and punched into the middle of the sheep’s ear between the ligaments. Black pigment is then rubbed in to the wound.
- It’s important to put plenty of pigment on the pins and make sure the sheep do not move when it first feels the pain. Don’t flinch, and grit your teeth once you close the pliers.
- You are very lucky if the ID is readable for much of the sheep’s life, and a vivid imagination is always useful when trying to decide on the ID!
- Ear notches for numbering. Here you use the top, end and bottom of the ear to punch a single or double notch made with special pliers that cut a piece out of the ear. Each position represented a numeral and you can build up multiple-digit numbers by combinations of notches. It’s always a brain taxing to work out the code in a hurry as you have to do mental arithmetic on each ear.
- In goats it’s possible to tattoo the underside of the tail.
Other temporary ID methods
Raddle
- Numbers can be made with raddle on both sides of the doe. They should be at least 200mm high and be readable from 10-15m away.
- They work best on short hair of fleece and may last for half a season before fading. Using raddled numbers and marks is a good idea for a temporary ID of multiple kids.
- Putting lots of raddle on the fleeces is bad practice. Use these tips when using an aerosol raddle:
- Shake the can well before use.
- Hold it upright when using otherwise the propellant will be used up before the paint.
- Use very sparingly.
- Squirt the nozzle near the required spot and only make the smallest dot possible (the size of a 10c piece when dry).
- Store aerosols in a cool place out of the reach of potential graffiti artists.
- You can get chalk raddle in a wide range of colours.
- It’s useful for short-term marking such as by the meat company lamb drafter.
- It usually washes off in about a week.
- It’s messy stuff to handle but a farmer has invented a plastic holder for the chalk sticks to keep your hands clean and the raddle dry when not in use.
- Only used approved products.
- These can be used for temporary ID in flocks at kidding where you don’t want to catch the doe to read her brass tag and cause disturbance, but they are a lot of work.
- You need a checklist of neck tag against brass tag.
- Neck tags can be made of all sorts of materials from tin and plastic lids to engraved Formica and letters need to be at least 40mm high.
- Tying the cord the correct length is important otherwise the doe gets her front legs though when grazing.
- It’s important to remember to remove all neck tags before shearing.
Coloured clips
- Coloured plastic clothes pegs can be used when selecting goats.
- Gripping paper clips can also be used on the fleece – and not on the ears!
Coloured wire twisters
- Use short lengths (about 100mm) of pliable coloured plastic wire that can be threaded through a brass tag and both ends twisted together.
- A wide range of colour combinations can be used and old electrical cable is a great source of wire.
New ID methods
Electronic tags
- These are now being used in some sheep breeding flocks where large amounts of performance data are being recorded.
- At the moment they can only be read when close to the sheep
- The potential is here for the animal’s complete data to be stored in its ear tag and act as a “passport” to record its complete history, such as feeding and health treatments and which farms it has been on.
- This is being driven by the need to track animals in disease outbreaks and concern over food safety and the need for “traceback” from plate to paddock.
- Costs of electronic ID will be easily accepted by breeders who keep detailed performance records and indeed it could help them, but it will pose problems for large-scale commercial sheep farmers.
- Put them in the goat’s left (near) ear to help the shearers.
Electronic chips
These would only be justified for very valuable animals as a protection from theft.
DNA profiling
- DNA profiling can be used where individual ID of kids at birth is not possible.
- Birth date is obtained by shedding off does that have not yet kidded, so the birth day is known for each paddock of kids when they are docked.
- Kids are tagged at docking (3 weeks old) and blood samples taken for ID profiling at a special laboratory.
- As the DNA data builds up in a flock, the parent’s ID of any kid can be determined to a very high degree of accuracy.
- Some labs use 6-7 genetic markers for sheep which breeders have found is not as accurate as manual recording. Only using 10-14 markers gives a high degree of accuracy.
- Using DNA markers, it has been shown that 25% of sheep twins had been sired by different rams – something that would have been unknown before DNA profiling.
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