ISU Extension
IA State Univ.
IA Dept. of Ag
IA DNR

October 2002

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In this issue
Farm Bill Decisions
Feed Costs Increase Pork Breakeven 
West Nile Virus
Hidden Soybean Yield Loss

Farm Bill Decisions
by Ron Hook, ISUE Farm Management Specialist

Signup for the 2002 Farm Bill is scheduled to begin October 1, 2002, and end June 2, 2003.  By April 1, 2003, landowners will need to decide if they are going to update their base acres and payment yields from those used in the previous farm program to those experienced over the past four years. 

There are several calculations that need to be completed when making this decision.  ISU Extension and Texas A & M have spreadsheets available at http://www.extension.edu/feci/ and http://www.afpc.tamu.edu/models/bya/, respectively, that make these calculations.

If you have a computer, you may access the ISU or A & M spreadsheets by going on-line to the appropriate address, by e-mailing rhook@iastate.edu to request a copy of the ISU spreadsheet to be sent as an attachment, or by calling (712) 754-3648 to request a copy of the ISU spreadsheet on a floppy disk. 

If you do not have a computer or desire some assistance, you may call and request an appointment to have an analysis done for your operation using the ISU spreadsheet or the Texas A & M Base and Yield Analyzer. 

In order to complete the analysis, you need the following information:

• The letter from FSA detailing the planted acres for 1998-2001 and 2002 PFC acres for each FSA farm number in the operation.
• The current program yields for the 2002 PFC acreage bases.
• The 1998-2001 yields for each crop that can be proven to FSA.

While the exact rules for proving yields have been and are still being revised, the basics of the program have been established.  If you don’t fully understand the details of the decision you are making, there is plenty of time to ask questions so that you can make the best decision for your operation.     

Feed Costs Increase Pork Breakeven
by Dave Stender, ISU Extension Swine Field Specialist

Feed prices have been rising due to loss of production and drought in parts of the U.S.  What is the impact of price changes in corn and soybean meal on your operation?  How high can corn and Soybean Meal (SBM) prices go?

A simple price matrix can be developed between price of corn and price of SBM based on your operations F/G (lbs of feed to lbs of gain) or FE (feed efficiency).  Suppose an operation has a 3.0 F/G.  This would be the same as stating it takes 300 lbs of feed to produce 100 lbs of live weight.  Finishing diets (50# to market), on average will be about 78% corn and 18% SBM  (remaining 4% would be premix and other ingredients … to simplify calculations use 80% corn and 20% SBM).

Example 1: Operation has F/G of 3.0  - uses 234 lbs (4.2 bushels) of corn and 54 lbs SBM to produce 100 lb live wt gain.

Table 1. Cost per cwt of gain changes as corn and Soybean Meal price changes (Note: only the cost of corn and SBM are included in the cost/cwt, no premix or other ingredient cost)

     SBM-$/ton     $150         $160            $200            $250
  ------------------------------------------------------------------------

Corn $/bu Cost of gain $/cwt

   $1.90   |           $11.99       $12.26          $13.34        14.69

   $2.00   |           $12.41       $12.68          $13.76        15.11

   $2.50   |           $14.50       $14.77          $15.85        17.20

   $3.00   |           $16.59       $16.86          $17.91        19.29

Example #1 = Rule of thumb for 3.0 feed conversion:

Corn - For every $.10 (dime)/bushel move, it will increase/decrease feed cost $.42/cwt of live weight
SBM - For every $10 /ton move it will increase/decrease feed cost $.27/cwt of live weight

How important is feed efficiency?

Example 2: Operation has F/G of 3.4  - uses 265 lbs of corn and 61 lbs SBM to produce 100 lb live wt gain.

     SBM-$/ton      $150         $160            $200            $250
-----------------------------------------------------------------------------

Corn       |

   $1.90   |           $13.59       $13.89          $15.12        16.65

   $2.00   |           $14.06       $14.37          $15.59        17.12

   $2.50   |           $16.43       $16.74          $17.96        19.49

   $3.00   |           $18.80       $19.10          $20.33        21.86

Example #2 = Rule of thumb:

Corn - For every $.10 (dime)/bushel move it will increase/decrease feed cost $.47/cwt of live weight

SBM - For every $10 /ton move it will increase/decrease feed cost $.31/cwt of live weight

Feed efficiency becomes more important as feed price increases.  Feed efficiency is impacted by genetics, feeder management (reduce feed wastage), ration formulation, market weight, general herd health, rapid temperature changes and other stresses.  It is important to pay closer attention to details during periods when feed costs are up and market price is down.

West Nile Virus
by Beth Ellen Doran, ISU Extension Beef Field Specialist

As of September 16th, 96 Iowa counties reported West Nile Virus (WNV) activity.  The Iowa Department of Public Health announced two additional presumptive cases, bringing the human total to 8 cases.  An additional 225 horses, 113 birds and 7 chickens have tested positive for WNV.  According to Nolan Hartwig, ISU Extension Veterinarian, this outbreak should be considered a serious episode.

West Nile Virus is a mosquito-borne virus that was first detected in the U.S. in 1999.  Mosquitoes acquire the virus from birds and pass it on to other birds, animals and people.  The virus is not directly transmitted from horse to horse, horse to people or people to people.  Experimental tests suggest that sheep, chickens, and pigs could be affected by the virus, but no cases in these animals have been reported in the U.S.  Cattle may show antibodies to WNV, but do not show any clinical signs or become ill.

Most people bitten by an infected mosquito will never develop symptoms.  Mild symptoms may involve fever, headache, body aches, occasionally a skin rash and swollen lymph glands.  More severe infections include high fever, neck stiffness, a decreased level of consciousness, confusion, tremors, muscle weakness and paralysis.  In rare cases, an infection can be fatal.  There is no vaccine or specific treatment in humans.  

The disease in horses can vary from unapparent to severe cases involving death.  Symptoms in horses include loss of appetite, moderate fever, "sleepy" appearance, aimless wandering, standing in one place with the head down for long periods of time, standing with hay protruding from the mouth, prostration, convulsions and death.  Horses should be vaccinated now, as the mosquito season may not be fully concluded.  The WNV vaccine is a killed product.  Two doses, approximate cost is $25, must be given three weeks apart, followed by annual vaccination. The two most effective ways to prevent the spread of WNV is to reduce the mosquito population and prevent mosquitoes from biting.

To reduce the mosquito breeding grounds:

• Empty containers that hold water, such as flowerpots.

• Cover tires stored outside so they cannot collect rainwater.

• Repair leaky outdoor faucets.

• Keep gutters clean and in good repair.

• Stock ponds with fish that eat mosquito larvae.

• Fill potholes and puddles.

• Change water every 3-4 days in livestock water tanks, birdbaths, pet bowls and wading pools.

Mosquitoes will be active in Iowa until the first hard frost.  As the weather turns cooler, mosquito activity during daylight increases, while night conditions become too cool for mosquito flight.

Precautions to reduce mosquito bites include:

• wear long-sleeved shirts and long pant

• use mosquito repellents

• repair tears in window and door screens

If you plan to use an insect spray on horses, use only products approved for horses.  Never mix an insecticide with petroleum products for application to horses.  Light blankets and hoods will also afford some protection to your horse.

Hidden Soybean Yield Loss
by Paul Kassel, ISU Extension Crops Field Specialist

The table below lists the amount of hidden yield loss that occurs when soybeans are harvested at less than 13% moisture.  Soybeans are sold at 13% moisture or 87% dry matter.  However, if soybeans are sold at less than 13% moisture you are substituting dry matter for moisture content.  Therefore, part of the soybean crop is, in effect, given away.

The table lists actual losses for different yield levels and moisture contents.  The rule of thumb values may be easier to remember and are listed as bushels per acre per point. 

An example is as follows: 50 bushel per acre soybean yield at 9 % moisture equals 2.4 bushel per acre hidden soybean yield loss (13% moisture minus 9% moisture equals 4 points of moisture times 0.6 bu/point/acre hidden yield loss, or 2.4 bushel per acre).

There is often little than can be done to alleviate this hidden loss once soybean harvest begins.  Some management things that can be done (within reason):

-        Plant soybean varieties with a range of maturities

-        begin harvest earlier

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