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How To Use Classification For Sire Selection
It is always apparent that most breeders spend more time looking for the right bull than they do finding the right cow to breed this bull to. What follows is an easy system using classifications which will help you to make the right selections.
To demonstrate the use of classifications I have taken a case study and these are the results.
• This is a true herd summary.
• Data of 57 classified cows in one herd.
Linear scores from a specific herd:
• Rump height: 46 are above, 8 are on average, and 3 are below the National Average.
• Angularity: 22 are higher, 23 are lower than the National Average, 12 are on average.
• Body Depth: 46 over National Average, 12 below.
• Rump angle: 26 over, 18 on average, and 13 below.
• Rump width: 21 over, 36 below.
• Rear legs side view: 25 more sickle, 14 correct, and 18 more straight hocked.
• Foot angle: 20 above average, 15 on average, and 22 below average.
• Fore udder attachment: 9 above, 10 on average, and 38 below.
• Rear udder height: 3 are above average, 32 are lower, 22 are on average.
• Ligament: 12 above average, 13 on average, and 32 below average.
• Udder depth: 20 above, 17 on average, and 20 below.
• Front teat placement: 40 above, 4 on average, and 13 below.
1. Rump height needs no improvement unless you are wanting to breed smaller cows then as is apparent the cattle in this herd are well above average.
2. Angularity. Roughly about 40% are angular. This will become important later.
3. Body depth outstanding. Needs no improvement but one would presume that this is what has been bred for. This is where classification proves itself. A goal was set and met or the type of cow that is surviving in this particular herd is a cow with extreme body depth. The proof would not have been there to see if this herd did not classify.
4. Rump angle. It is clear that the majority of cattle in this herd show slope to the rump. An interesting observation that I made while classifying this herd is that there were a large number of old cows in the herd. Maybe this is because the herd as a whole has more sloped rumps. Another aspect that would not have been seen if there had been no classing done.
5. The rump width is very much on average. I accept that because the rump angle is, on average sloped that the rump width on average would be slightly more narrow than wide. As is the case in this test 36 are narrow and 21 are wide. Once again proof that the system works.
6. On straight hocked or sickle hocked there appears to be no definite problem. It would be up to the breeder to decide the direction in this case. However, it makes it easier for the breeder to make a decision. If the breeder of this herd finds a bull that suits the herd in everyway possible but is straight hocked or sickle hocked then at least he or she will know that they can still use the bull. Obviously it would be important to carry on classifying to monitor the results.
7. The foot angle shows that there is not a huge problem. I did feel in this case that the poor foot angle in certain cases was caused more by environmental factors than by genetics. Once again it proved that if I had not been on the farm to explain and address the problems that this would not have been realised. This herd could have carried on breeding for foot angle as their main problem without realising that all they have to do is look after their cattle’s hooves better.
8. Fore udder attachment, rear udder height and medium ligament proved to be this herds main failure. According to the breeder they realised that this was where their short falls lay they had not really seen how severe it was. They had never really compared their herd’s udders to anyone else’s. Now, for the first time they could make the comparison and start sorting it out.
Selecting the Bulls for this Herd
1. It becomes extremely easy to do bull recommendations in this herd. If the breeder is happy with the angularity of the herd all they need to do is to divide the bulls into two groups. The two groups will be bulls that breed less angular and bulls that breed more angular. We have seen that roughly 50% of the herd show more angularity. All the cows that score higher than the national average for angularity must be bred to the bulls that are breeding less angularity. The breeder must decide which direction he would like to head in when it comes to the cattle that score the same as the national average. If they believe that a stronger type of cow does better then they must use the bull breeding less angularity on this group but if they believe that angularity is important then this group must be bred to the bulls breeding more angularity.
2. Further we know that they must use bulls that will improve the fore udder attachments, the rear udder height and the medium ligament. In this case due to the environmental conditions they do not want to compensate body depth or foot angle.
3. Now they need to decide on the production criteria preferable obtained from their milk buyer and from their milk records.
Now all they need to do is find bulls that fit into these categories. Think how much time and money it will save this breeder the next time you need to buy semen. This exercise will take them at the most one hour but just think of the peace of mind when they inseminate a cow.
Linear Characteristics:
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