Selection: A Force for Change

April 27, 2009

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769: a two year old heifer with her first calf; nursing, just twenty minutes after being born unassisted.  Observe her maternal instinct as she licks her calf.  She is undisturbed by my taking of her picture a few yards away.  Anyone who has raised cattle knows that it isn’t always this easy.  The following post will explain how we select for these traits.

 

Selection:  “A natural or artificial process that results or tends to result in the survival and propagation of some individuals or organisms but not of others with the result that the inherited traits of the survivors are perpetuated.”  Webster’s

A geneticist has a powerful tool with which to change a population:  Selection.  A herd is a moving population of genetics.  The selection decisions each farmer makes will determine the future of his/her herd.

I just had a revelation.  Selection is also what changes our personal lives.  The choices we make determine to a large extent the content and quality of our life.  Do I put as much thought and effort into personal life decisions as I do in selection decisions for my herd?  How about you?  Do you map out your life, or does it just happen to you?

“The best way to predict the future is to create it.”  Peter Drucker

 

My parents went on a bull-buying trip to Leland Red Angus Ranch in North Dakota. They purchased three bulls for $7,650.  Most farmers don’t spend over $1,500 on a bull.  Why are we willing to spend more?

In many respects we are frugal farmers.  We don’t own any one piece of machinery worth $7,650.  Why would we spend that much on bulls?  Simple, we understand and value the tremendous genetic contribution a bull, (herdsire), makes in a herd.

Our cowherd consists of 135 cows and 5 bulls.  A bull has 27 times the genetic impact of a cow in our herd, (135 divided by 5).  Some may argue that we should spend more on our bulls.  The cost is ancillary.  Finding the right bull for our herd is the main thing.  How do we know which bull is “right” for our herd?

I will explain which selection factors are important to us and how we choose a herdsire.  We have simplified our selection criteria into four main factors and in this order of importance:

1.  Disposition/Appearance

2.  Calving ease

3.  Fertility

4.  Maternal Soundness

If these four criteria are successfully met, we will start to look at other factors such as growth and carcass traits to choose between two similar bulls.  This is probably opposite of most in the cattle industry.  Growth and carcass traits usually receive top merit and our four criteria receive much less selection weight. 

Why is this so?  Have you heard the golf saying, “drive for show and putt for dough?”  What this refers to is most golfers want to impress their buddies with a super-long drive and will spend much of their time practicing that aspect of their game.  Analytical golfers know that the club that takes the most strokes is the putter, and any improvement there will have the greatest effect on reducing their scores.  But putting isn’t sexy.

In the cattle industry, most people want to wean big calves and brag to their buddies about the awesome growth of their cattle.  Unfortunately, growth is negatively correlated with percent calf crop.  Percent calf crop, (the number of calves weaned compared to the number of cows in a herd), is the number one production parameter by far when predicting profitability.  But percent calf crop isn’t sexy.

Selection criteria that will affect percent calf crop are: calving ease, fertility, and maternal soundness.  A cow needs to have a live calf, successfully raise the calf until weaning, breed and have a calf next year.  That is why we select for these three traits.

Why is disposition/appearance on the top of our selection criteria?  It is a convenience trait.  A convenience trait is something that makes life easier. 

We like to have a calm setting when we work with our cattle.  It’s better for the people and better for the animals.  Much of that can be accomplished with excellent animal handling and we always strive to approach our animals with patience.

But disposition is also highly heritable.  We make our life easier by maintaining a genetically calm herd. 

Appearance is also subjectively evaluated at the same time as disposition.  We want to raise animals we enjoy observing.  This may seem silly and unscientific, but I suspect years of observing cattle causes us to favor functional cattle over unbalanced cattle.

Now you know what we select for in our cattle.  How do we select?

The first selection is the selection of a breed.  Choose a breed based on its strengths, what it’s known for.  Red Angus is known for calving ease, fertility, good mothers, marbling.

The next selection is the selection of a herd.  We want to buy bulls from a breeder that has similar philosophies and management as us.  Like most people, we also prefer to buy from someone we like and trust.  It’s important to visit the farm and meet the producers and see the cattle before the sale to alleviate time crunch.  We make farm and ranch visits a part of our vacations.  Producers are always happy to take a couple of hours to show you around their place.  My parents and I have each visited Leland Red Angus on separate occasions.

Now we come to bull selection.  Disposition, our most important trait, has to be evaluated in person.  We approach a bull and observe his behavior.  Disposition is a pass/fail trait.  The bull should quietly walk away from you as you come closer.  This would be a pass.  He fails if he runs away with his head up in the air; too flighty.  He also fails if he holds his ground or approaches while shaking his head.  This is aggressive and dangerous behavior which will only get worse as he gets older.

We have experienced one other type of behavior in the Red Angus breed which is worth noting.  The ultra-quiet bull will not exhibit any aggressive behavior; but will not walk away when approached.  We thought this was a positive and selected two bulls in the past like this.  We now classify this behavior as a fail.  The reason?  Each of these bulls turned aggressive after a few years.  We think it’s because they failed to respect us.  Disposition can be taken too far.  Animals can be too quiet.  What about our other traits?

Fortunately, calving ease, fertility, and maternal soundness cannot be selected to an unhealthy extreme, unlike most traits.  We are striving for 100% success in each of these traits.  How do we select for these traits?

Maternal soundness is the ability of a cow to take care of her calf.  She has mothering instinct.  She has enough milk for her calf to grow well.  Yet she doesn’t give so much milk that her udder begins to lose form and her calf has a difficult time nursing on a too-large teat for the first time.

Selection for this trait can be done two ways.  Make sure the herd you are selecting from doesn’t make excuses for a cow that fails to wean a calf.  They should have a philosophy of culling problem cows.  And observe the cows and specifically the mothers of the bulls you are thinking of buying.

Calving ease and fertility are best selected by using modern genetic evaluation programs.  The Red Angus breed has a genetic evaluation tool called EPDs, Expected Progeny Differences.  EPDs show the relative genetic merit of an individual within a breed.  The easiest way to use EPDs is to look up the breed percentile rankings for the EPD for each trait you are selecting for, and then determine how well you want your herdsires to rank.

Fertility is expressed with an EPD called Stayability.  Stayability predicts the odds that a cow will have a calf every year until at least the age of six.  The Red Angus breed used the age of six because economic research shows that this is the age when a cow begins to show a profit.

Calving ease is expressed in two ways:  calving ease direct and calving ease maternal.  Calving ease direct predicts the odds that a bull’s progeny will be born unassisted.  Calving ease maternal predicts the odds that a bull’s daughter will have her first calf unassisted.

Based on experience and availability, I wanted bulls that ranked in the top 40% of the breed for these three traits.  Leland Red Angus sends out a sale catalog before their sale with all of this information and more.  I went through the catalog and found 45 bulls that met my criteria out of 153 bulls available. 

My parents drove to Leland’s and evaluated the 45 bulls before the sale.  They eliminated some based on appearance and disposition.  The bulls that would work for us they assigned a relative value in dollars to guide our purchase during the sale.

They ended up purchasing bulls 41, 118, and 145.  I calculated the average EPD’s for the three bulls they purchased and congratulated them on a job well-done.  The three bulls averaged in the top 15% of the breed for calving ease direct, top 10% for calving ease maternal, and top 20% for stayability.  Because of selection, our future looks bright!

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Genetics or Environment?

April 5, 2009

I sold showpigs to 4-H and FFA students this past week.  Showing swine is near and dear to me as I probably wouldn’t be farming today if it weren’t for showing swine.  Striving to improve on my placing at the Lafayette County Fair caused me to begin my life-long study of genetics and improvement of livestock through selection.  Check out “How I Became a Swine Seedstock Supplier.”

Our swine show is an excellent learning opportunity.  Showpigs are weighed and identified in April.  The maximum weight was 88 lbs. on Saturday. 

The students then have the responsibility of caring for the swine until the show in July.  After the show, each student is allowed to sell one showpig in the livestock auction.  Local businesses support the students by purchasing a pig or other species of livestock.  Prices are usually above market price so the students are almost guaranteed to make money on their livestock project.  Students are also required to keep production and financial records on their livestock project.  Students learn responsibility, accounting, and marketing skills all in one fun project.

Not everyone is successful, however.  There is a minimum weight, (220 lbs.), to sell in the livestock auction.  This requires an average daily gain of about 1.5 lbs per day, (170 lbs. of gain in 113 days).  This is not difficult to accomplish with today’s swine.  However, to achieve this average daily gain, a pig needs clean feed and water, shelter, shade, and a way to cool off, (sprinkler or wallow), when it gets hot.  If a student fails to provide these ingredients every day, he/she may find his/her pig is too light to sell at the auction.  Another great learning experience.

One family had never purchased from me before.  I helped them deliberate whether a smaller pig, (46 lbs.), would be big enough by fair-time.  They asked me how well my pigs gain weight.  I told them average because I was more interested in what their pigs have weighed at the fair in the past.  I asked this because it’s been my experience that families tend to have similar experiences from year to year even though the pigs are different.  Some families always bring 300 lb. pigs to the fair.  Other families always struggle to make the minimum weight.

This is easily explained because average daily gain is only moderately heritable.  Heritability is expressed from 0 to 1 with 0 being not heritable and 1 being completely heritable.  Average daily gain in swine is about .3.  This means that 30% of the variation in average daily gain is due to genetics. 

What causes the other 70%?  Environment!  That explains why the people managing the pigs are a much greater factor than the genetics of the pigs.

The family decided to take the smaller showpig.  I will let you know how they did after the fair in July.

What are you blaming genetics for?  Could your environment be a greater factor?

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Better-tasting Pork: Fat is where it’s at

February 6, 2009

Your job as a direct-marketer is two-fold.  Marketing:  make the sale.  Production:  produce a product that turns a casual customer into a repeat customer.

Most people have never eaten a juicy, flavorful pork chop.  There are two reasons for this:  overcooking and too-lean pork.

Fat is where the flavor is.  I read that blindfolded volunteers could not tell the difference between pork, beef, or chicken meat, if  all the fat was removed from the protein.

People will continue to overcook pork.  However, pork with more fat will stay juicy longer.

What can we do as direct-marketers? How can we increase the odds that our customer will have an excellent eating experience with our pork?

We can educate our consumers and change our swine genetics.  This takes time and is an ongoing process.  Hand out cooking information, talk to consumers about how they cook, select boars with more intramuscular fat, (marbling).  Some of the breeds such as the Duroc and Berkshire have boars that are clearly superior for intramuscular fat.  We have used some of the Durocs from SGI to increase the marbling in our pork.

But there are two things you can do right now.  Take your hogs to heavier market weights and only use barrows for your direct market. 

In the 1980’s most market hogs had over an inch of backfat at a market weight of 220-250 lbs.  The meatpackers began to demand a leaner hog and were willing to pay for it.  They also asked for heavier hogs to increase their throughput.  Swine geneticists took the cue and bred hogs that stayed leaner to heavier market weights. 

Consumers didn’t want fat either.  The Pork Checkoff  jumped on the lean bandwagon and began to advertise, “Pork, the other white meat”.  Consumers thought they were buying a chicken-like product and in many respects they were.  However, pork doesn’t make good chicken.  So we ended up with drier, less flavorful, more expensive than chicken, chicken-like pork.

Now everyone has realized the pork industry swung the leanness pendulum too far.  Changes have been made in the industry.  The meatpackers changed their buying grids to no longer reward the super-lean hogs.  However, it takes a long time to change the nation’s swineherd and pork is still quite lean.  This is where your opportunity as a direct-marketer lies.

Many of our pork customers tell us one of two things.  “We have never had pork like this before.”  Or, “this is the pork I remember from my youth.”  Either way we’re golden because we are creating a noteworthy eating experience for them. 

Back to what you can do right now to improve your pork.  Hogs have more marbling the heavier and fatter they become.  We shoot for a 220+ lb. carcass which means the live weight is 300+ lbs.

We only use barrows for our direct market.  Barrows have about .2 inch more backfat than gilts and correspondingly more marbling.  Also, there can be quality issues if a gilt is butchered when she is in estrus.  Barrows are a sure thing. 

There are two disadvantages to taking your hogs to heavier market weights.  Feed efficiency is reduced as hogs grow larger.  And an athletic 300+ lb. hog can be quite a challenge to load.  Happy marketing!

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