# estimating weight of pigs



## Jhammett (Apr 10, 2013)

I have found a few sites with formulas such as
heart girthXheartgirthXlength /400= weight
then I found a chart that simply takes Heart Girth and gives a weight based on that. For example it says a pig with 39 inch heart girth will weigh 191lbs (+,- 10lbs). has any one used these formulas or charts? How acurate are they?


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## cooper101 (Sep 13, 2010)

They're pretty accurate, but plus or minus 10-20 pounds. My pigs wind up being pretty square with the girth and length usually very close to the same number, so that's probably where the girth-only chart idea comes from. Body types vary, so not all pigs will measure the same in girth and length. 191 pounds with 39 inch girth seems a pretty big over-estimate, though. That pig would have to be 50 inches long for GxGxL/400 to work out. That's one long, skinny pig.

It is fairly accurate to measure them, but I find it most useful after you accumulate some data based on your experience. I know that if my pigs average 46-48 inch girth, they'll come in where I expect them to in hanging weight. Other little cues help in estimating weight as you go. I can tell it's butcher time when only a certain number fit at the trough. If the carcass hangs within 2-3 inches of the floor of the truck, it's over 200 pounds, etc. You'll get better at estimating.

I would recommend using the GxGxL/400 formula, measuring the day you butcher, then comparing that to actual hanging weight. Then you can see how close or far off you were and adjust with the next pigs.


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## highlands (Jul 18, 2004)

This is what we do every week. I call it weighing a pig with a string. Although actually I usually use a stick with marks on it or sometimes a tape measure. I often just go for the measure length as I know our pig's ratios well. It's accurate enough for picking pigs to go to market each week and generally gets the roasters pretty well on target.

http://sugarmtnfarm.com/2006/01/13/how-to-weigh-a-pig-with-a-string/

It's a quick and easy way to estimate the pig in a field's yield.

Also of use is that:

Hanging Weight = Live Weight x 72%

Commercial Cuts Weight = Hanging Weight x 67%

This will vary with slaughter method (above is for scald & scrape) and how fat your pigs are (ours are about 0.75" to 1" of back fat). Note that there is a lot of good meat between the Commercial Cuts Weight and the Hanging Weight.


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## Jhammett (Apr 10, 2013)

[/QUOTE]Note that there is a lot of good meat between the Commercial Cuts Weight and the Hanging Weight.[/QUOTE]

What do you mean by this this is the second time I've seen you say this. How do I get that meat if hog is at butcher??


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## gerold (Jul 18, 2011)

Note that there is a lot of good meat between the Commercial Cuts Weight and the Hanging Weight.[/QUOTE]

What do you mean by this this is the second time I've seen you say this. How do I get that meat if hog is at butcher??[/QUOTE]

If you butcher yourself you can save just about everything on the pig. A lot of processors discard a lot of good parts from the pig.


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## cooper101 (Sep 13, 2010)

You have to ask the butcher to save it. They make a lot of assumptions when throwing away stuff like heads, organs, feet, tongues, etc. Most people don't want it, so it usually gets tossed out and they often don't ask.


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## highlands (Jul 18, 2004)

Jhammett said:


> > Note that there is a lot of good meat between the Commercial Cuts Weight and the Hanging Weight.
> 
> 
> What do you mean by this this is the second time I've seen you say this. How do I get that meat if hog is at butcher??


Many people don't want the head, feet, liver, kidneys, tongue, skin, back fat, tail, bones. These get trimmed off between the hanging weight and the commercial cuts weight. There is also a little loss to trimming in there but most of this is good to eat. There is growing awareness of these oddment cuts.

To get it, ask for it. Note that if skinning is done then many of these cuts aren't available. Some require scald and scrape. e.g., feet, skin, tail, etc. Not all processors are setup to do scald & scrape.

For more about what is good on a pig see:

http://sugarmtnfarm.com/2012/05/03/what-good-is-a-pig-cuts-of-pork-nose-to-tail/

-Walter


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## abachler (Sep 12, 2016)

Jhammett said:


> I have found a few sites with formulas such as
> heart girthXheartgirthXlength /400= weight
> then I found a chart that simply takes Heart Girth and gives a weight based on that. For example it says a pig with 39 inch heart girth will weigh 191lbs (+,- 10lbs). has any one used these formulas or charts? How acurate are they?


I think Girth squared times length divided by 400 is probably more accurate for hogs near market weight, but it gives completely unreasonable numbers for smaller hogs. e.g. my hogs are currently measuring 27.5 girth 24 inch length, which says they are 45 lbs. the table I read says based on girth only they are closer to 75 lbs. I don't have a scale to weigh them, but the 75 seems more likely given their size.


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## highlands (Jul 18, 2004)

I use the LGG/400=LiveWeight method all the time on all sizes of pigs and find it to be reasonably accurate. I use it for roaster pigs as well as finisher pigs and larger cull breeders.

It does require skill, it's a learned thing. Do a lot of pigs and you get better at it. The position of the pig when measuring length and where you measure the girth matter a lot. 

Since I know the L:G ratio on our pigs I tend to just do a quick estimate with a stick for L(length). Note that I'm doing it on my breeds which are Yorkshire, Berkshire, Large Black and crosses for the most part. It is possible that there are some breeds where it won't work as well as it is based on density.

See this article which includes a diagram of how I get the measurements:

http://sugarmtnfarm.com/2006/01/13/how-to-weigh-a-pig-with-a-string/

-Walter


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