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The second most cause of enforced culling - Legs!

Foot and leg problems together with lameness are still a major reason why sows have to be removed from the herd in the first 3 parities.

Foot and leg problems together with lameness are still a major reason why sows have to be removed from the herd in the first 3 parities.
The problem definitely starts with the gilt. 40 years ago I was helping to select both bought-in gilts from multipliers, topped up with those available at the local market - the latter not acceptable practice today. Whatever - I selected many hundreds of gilts over 4 years and got quite good at it, as could be expected from such long practice. A real benefit was to be able to follow `my`gilts as sows on our very large 1200-sow farm and learn from my mistakes.
It would take 20 textbook pages to describe how to select a good gilt conformation-wise, here I confine myself to a few key points on legs alone.
General
• Take special care in scrutinizing fast-grown gilts, like 750g/day compared to 550g/day. These are the right gilts to go for but they need extra-special examination (and easing-up before service, but that`s another story).
• Note how she walks. Fluid movement (almost sexy!) Goose-stepping? Out at once!
• If you can, look for any which seem stiff on getting up and down. Reject.
• Nice `springy` pasterns - not `soft` ie. acutely-angled.
• Good base width of both front and rear legs, one at each corner. Reject narrow-set legs.
• Large feet are always best.
Front legs and feet
• Toes big, even-sized. Over 12mm difference - reject.
• Small, narrow toes will be very likely to deteriorate faster. Reject.
• Reject splay feet and the opposite - pigeon-toed.
• Swellings, cracked hooves, foot pad abrasions (if seen), reject.
• Buck knees - reject. This is genetic.
• Nice angle between shoulder and upper leg. Straight down, ie `tippitoes` is bad, they`ll have difficulty getting up and down later in life, especially in stalls. Difficult to describe - you need to be shown this from good and bad side view examples.
Rear legs and feet
• Again, from the side, a nice angle between hip and the two upper leg bones ie. as with the front legs, `tippitoes` (at too straight an angle) is a genetic no-no. They get stiff, especially on concrete. And arthritic?
• Reject straight rear pasterns, the opposite - weak excessively-angled pasterns and sickle hocks. Seen from the rear, turned-in `cow-hocks` are always rejects.
• Reject overlong dew claws, damaged dew claws, cracked and damaged hooves.
• As with the front feet, look for even toes, noticeably well-spaced apart.
Bone strength from the conformation viewpoint
The lower leg bones cross-section of breeding females should not be excessively `aerofoil`, called `fine boned, or too rounded as in a circle, but more of an egg-shape with the egg cut in half vertically, the blunt end forwards in cross-section.
I hope this helps. Practice makes perfect!

4 comments

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    Jim Fiedler (Fiedler Family Farms)

    John...I raise grassfed beef & sheep and pastured Large Black pigs that are NEVER indoors. I keep my cows until they don't perform which can be nearly 20 years old for the best. But I can find no help on how long I can keep good pastured sows & boars since so most people get rid of them by the time they are 3 years old. Any ideas?

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    jenniferchalipo

    its very hard to observe all those abnormalities in choosing a quality sow in a herd, can u pls post a picture of good picture of gilt to be a sow in terms of physical aspects.

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    John Gadd

    Jim Fielder.
     Sure, how long to keep her is one of pig farming`s eternal problems! As long as she`s as profitable as the cost and performance of  the gilt replacement for her is the quick answer. But to be more helpful to you and others: -

    Sow longevity is related to high fertility levels and low non-productive days. Lifetime litters per sow is a trade-off between the cost of empty days per litter (or per sow per year) so you must monitor these carefully and compare this cost with the lower cost per finished pig of keeping her longer.
     I give below the benchmarks I use myself....

























    Poor


    Typical


    Good

    Action level

    Per
    litter

    28

    15 to
    23

    12 to
    13

    16 plus

    Per
    sow per year

    53

    35 to
    56

    28 to
    30

    35 plus



    To help you further, read the chapter on `Culling Strategy` pages 63-72 in my textbook "Pig Production Problems - John Gadd`s Guide to their Solutions" Nottingham University Press (2003). The two Checklists - `When to cull` and `When not to cull` you should find invaluable, so readers tell me.

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    John Gadd

    Jennifer Chalipo

    Yes, getting down to the vital job of gilt selection is a pain, but it is because this is not done well enough (not enough time spent on the inspection) is a main reason, but certainly not the only one, why so many sows don`t last more than 3 litters.

    You ask for a picture of an `Ideal gilt` and because as an advisor I have to be `All things to all men` I think it best if you write to the better-known breeding companies to send you pics of their latest `models`. I`ve noticed superb conformation in virtually every aspect (what the scientist calls `phenotype`) - in my travels across the world since last autumn in those from JSR, Topigs and PIC - there must be others of course - but these were the ones which impressed me the most. Quite a bit of variation does come from the different selection dedication/intensity of the multipliers they use, but these seem to be pretty consistent at present. Having said this - you cannot select a good gilt which will give long service from looking at a picture, any more than you can tell how nice a person underneath a beautiful film star is.

    The chapter on `How to Choose a Gilt` and especially the Progress Inspection Chart (p.81) I`ve used in selecting hundresd of gilts myself, is in the textbook referred to above.

    Sorry to push the book again but it is the quickest way for you to get all the information you need.

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