September 4, 2008

Condition Scoring (CS) Dairy Cows

 Cattle, farming, husbandry, body condition scoring, easy method to learn & use, implication of scoring errors, replacing body condition

Condition Scoring (CS) Dairy Cows

 By Dr Clive Dalton
You would think that everybody in New Zealand would know how to CS a cow. Well they don't. Let's check the history first.
1. CS has around for a long time. Ralph du Faur was the first one to describe it – maybe he invented the NZ system? The "NZ Farmer magazine reported du Faur's system in 1976.
2. The concept has been used in other countries for a long time using fewer scores.
3. The NZ system was described in detail in the 1970s by MAF's Te Awamutu farm adviser David Buxton. David wrote a detailed AgLink on the subject bristling with diagrams and black and white photos. It was comprehensive but hard going if you were not dedicated!
4. Then Livestock Improvement simplified the job by producing pictures in colour of cows backs and rear ends. This was much better and these were readily available until fairly recently.
5. For years at the Ruakura Dairy Farmers' open day we always had 2-3 cows on display with their CS written on their sides in large letters. Farmers learned little from this as they could not handle the cows.
6. This continued into the days of the Dairy Research Corporation (DRC) which morphed into Dexcel and again at open days cows were displayed with CS numbers on their sides. The learning I believe achieved was minimal.
7. Dexcel (now DairyNZ) continues to cover the subject at open days and in 1995 every farmer got a reference book with pictures of the same cow digitally altered to show different scores. It was reissued in 2008. This was welcomed by anxious MAF animal welfare officers who had to deal with skinny cows and needed a "gold standard" for reference in prosecutions. Dexcel even produced a DVD for farmers describing the NZ system.
8. So there has been no shortage of material over the years. The question is – how much of it has done any good? My feeling is – not a lot.

Some key points
  1. Condition scoring is not a precise science.
  2. The NZ system of 1 (near death) to 10 (obese) is far too complicated and it is not easy to learn.
  3. But nobody ever complained and told the technical experts, consultants or teachers that it was too hard have they? Everyone kept quiet in case we exposed our mental limitations!
  4. If the system was easy to learn, we would not have cows that fail to meet the well accepted CS of 5 for cows at calving – and there must be millions in North Island herds.
  5. But every farmer knows that a cow must calve at CS 5 and a heifer at CS 5.5. He/she has been told this for decades and the financial implications of failure.
  6. What is more, if CS is hard to learn – then it's hard to teach as the latter is the key to getting all staff members competent at scoring accurately. What's the point in having a system where you have to pay a consultant to do for you?
  7. The biggest point of all! CS is a "target" that all animals in the herd have to reach, and was never meant to be an "average".
  8. The concept of an average CS is daft and dangerous without a measure of the range around the average and the shape of the distribution.
  9. Discussion groups were so predictable when asked what you thought the herd average CS was. The trick was always to say 4.5, especially if you were asked first, as 4.5 is non-confrontational. All the others would say "around 4.5". If you were feeling a bit bolshy say 4.4 or even 4.3, but if you wanted to please the hosts say "around 4.6 or 4.7". So the rule is - when in doubt use the "fudge" score of 4.5 and you'll never be a threat!
  10. Experience from teaching is that most farmers, vets and consultants are at least half a score too generous so most cows at 5 are really 4.5 and the very popular 4.5 cows are in fact CS 4 or below. Some farmers and professionals are a whole score too high.
  11. This should be no surprise as we were never taught how to CS, and we were certainly never tested to see how accurate and repeatable we were.
  12. Presumably farmers were supposed to learn on their own from the LIC photos with help at Discussion Groups.
  13. There are three conclusions turors come to when students don't learn. (a) - the students are dull, (b) - the material is inherently difficult (like maths) and (c) - the teaching is poor. Point (c) is the real problem but (a) and (b) always get the blame.
  14. So after teaching a student, listen to them teaching someone else and then you'll hear what you said! Go over it again and get them to teach you.
All you need to know
The present system is too complicated so try this. It's based on only knowing three scores and it's probably all you need to know.

The traffic lights
You only need to know three scores:
  1. GREEN: CS 5. The cow has rounded hips. Put you hand on the cow's hip bone and you cannot feel any flat area. The whole hip will fill your hand.
  2. ORANGE: CS 4.5. Use the palm of your hand to see if you can feel a flat area on the top of her hip bone as it has a very flat top. Then "jiggle" your fingers along her spine in front of her hips to feel for bumps and hollows between the vertebrae. If she has flat hips and a bumpy back bone – she's a 4.5.
  3. RED: CS 3. This cow has a very pointed shoulder (when it's head is up). It's like the ridge on Mont Cook with big hollows either side where all the muscle has gone. This cow is "emaciated".
Messages from the lights
    • Green: GO: - cows have no problems.
    • Orange. CAUTION: Too many farmers think they are greens. They still need feeding well. CS 4.5 is a useful working score for the cow and if you go down below this (by accident or design) - understand the consequences. You have to find the feed and the time to put it back. (1CS needs from 130-250 kg DM to replace).
    • Red. DANGER: this is disaster as CS 3 is officially "emaciated" and you'll need a rapid rescue mission from here that will take large inputs of feed and time to respond. You could also end in court under the Animal Welfare Act 1999.
Forget about
    • Using half scores.
    • Using decimal places for scores between the half scores.
    • Using herd average scores. These are the most dangerous things around as without a range in values around the average you can so easily be lulled into complacency.
Buy some scales
Dairy farmers never saw the need for scales, despite the fact that feeding cows or any animal for that matter is based on live weight for maintenance. Scales were considered to be too expensive and not necessary when Condition Scoring could be used instead.

This argument is no longer valid. When you live with cows every day it's hard to notice a slow decline in condition. Scales will show a weight change quickly (realising variation in gut fill in ruminants), and this will be seen long before there is a change in body condition. A small change in average weight will certainly alert you to check condition too.

You can't rely on visitors or friends to tell you that your cows are slipping in condition can you – they'll tell you if asked that the cows will average 4.5!

Scales don't tell lies and with modern systems are a valuable aid to feeding and animal health.

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