Make use of condition score to aid production
Published 28/09/2010 | 05:00
Being able to condition score cows is a valuable tool and is not a hard skill to learn. The ability to use this skill to make timely decisions this autumn will help maximise your milk production and reproductive efficiency in 2011.
Essentially, condition scoring is an assessment of the relative amounts of subcutaneous body fat or energy reserves in the cow. The cow is appraised through a combination of handling and visual assessment, and ranked relative to a condition scoring system. The main scoring system in use in Ireland runs from a score of 1 (extremely thin) to 5 (very fat), but in general scores of less than 2 and more than 4 are rarely found on commercial dairy farms.
The aim is to achieve a cow that has a condition score of 3.25 at calving, which then loses no more than 0.5 of a condition score to be >2.75 at mating. Hitting these targets for many cows will need decisive action this autumn.
To develop your skills in condition scoring, the first step is to calibrate your eye by handling around 10-12 cows in the collecting yard or crush to determine the amount of flesh covering the key body points of the backbone, ribs, short ribs, hip bone, thurl (area between hip bone and pin bone), pin bone and tail head. Table one (right) outlines the differences to look for.
The aim is to differentiate cows with condition scores between 0.25 of a score as listed above. A quarter score system is used as it's simpler and more reliable than spending five minutes debating whether the animal in question is a 2.9 or a 2.8. Therefore, determine whether the animal is closer to either a condition score of 3 or 2.75. I actually find in practice it is also easier to break a cow into two halves. I score the front half first, by considering the backbone, rib, and short ribs, and then the back half of the cow by looking at the hip, pins, and tail head, and then average out the score.
My reason for doing this is that some cows can be fit at the front and lean at the back. This is a characteristic typical of Holstein Friesians. In comparison, an animal with New Zealand Friesian breeding is a blockier, shorter and rounder animal with fat distributed more evenly around the body. Animals with prominent Jersey breeding have a very narrow body with prominent hip bones, so take consideration of these breed differences.
Once you've calibrated your eye, it's time to score around 20-30pc of the herd (scoring 30 cows from a herd of 100 should take no more than 15 minutes). Scoring visually in the paddock relies on the animals being judged with quick, snapshot decisions. This number of repeated assessments and variation within the herd will actually determine a reliable average score for the herd, as shown in Table 2 (above).
The herd average score is calculated by dividing the total score (B) of 106.25 by the number of animals (A), in this case 38. The average score of this herd is 106.25/38 = 2.8.