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Articles from 2005 In February

Joe Vansickle

Joe Vansickle

After leaving his home state of Indiana, Joe graduated from the University of St. Thomas in St. Paul, MN, with a bachelors degree in journalism. The Senior Editor on National Hog Farmer, Joe has been on staff since 1977. He specializes in animal health issues, federal regulations, environmental concerns and food safety. Joe has won several writing awards from the Livestock Publications Council. In 2002 he earned the Master Writer Program Award from the American Agricultural Editors’ Association.

Dale Miller

Dale Miller

Dale grew up on a Minnesota hog farm and graduated from the University of Minnesota with a degree in animal science. he has been with National Hog Framer for 32 years, serving as editor for the past 11 years. Dale has traveled to most states and foreign countries, studying and reporting on pork production practices throughout the world. Dale’s writing and photography have won numerous awards including the 2003 Minnesota’s Magazines & Publications Association’s Gold Award for Best Regular Column. He also received the 2004 Honorary Master Pork Producer Award from the Iowa Pork Producers Association and was honored in 2003 with the Distinguished Service award from the National Swine Improvement Federation. Dale stays active in pork production by raising purebred Chester Whites, Yorkshires and F-1 gilts.

Ten Simple Rules to Profitability

South Central Management Associates (SCMS) has identified 10 cost control points for pig owners to follow in SCMS' contract, wean-to-market program to successfully maximize their returns.

The pork industry is enjoying very profitable times right now with high hog prices and low grain prices. Seldom do both of these factors line up to produce such prosperous times.

However, Steve Hargis, director of operations at SCMS, says producers should not forget the havoc that struck in 1998-2000 when prices plummeted to record lows. All it would take is a sudden shift in pork demand or exports, and prices could start tumbling again, he warns.

SCMS oversees contract production of about 800,000 pigs/year on 160 sites in Iowa and Minnesota (one site in Illinois) in their wean-to-market program.

Most pig owners contract with independent growers. The growers receive $36-$42/pig space to house and feed weaner or feeder pigs in mostly 4,000-head barns.

In good times and bad, Hargis and logistics manager Pete Merna preach that profitability for pig owners depends on sticking to 10 cost control points.


Identify a source of pigs to buy from long-term. “Pete and I both feel that the ideal situation would be a long-term (five-year) contract that will get you a fixed price; for example, $33 per head for segregated early weaned pigs,” says Hargis. “The goal is to take all of the market fluctuation out of it.”

Owners buy pigs through SCMS from a variety of sources; about 70% of the pigs come from Canada because they can provide steady volume.

The biggest challenge right now is locating large volumes of high-health pigs for finishing. Company policy requires that a “vet-to-vet” health check be done on every group of pigs purchased, says Merna. About 20% of groups are rejected. Chief concerns are porcine reproductive and respiratory syndrome (PRRS), Haemophilus parasuis and Actinobacillus pleuropneumonia.

“We've got a lot more people looking for pigs than are available,” says Merna.


Identify what packer you will sell your pigs to. Don't just stop at signing an agreement. Pick a packer who wants the type of market hogs that you can provide.

You can go a long way toward controlling your costs if you select a packer who wants the weight of hogs and the type of genetics you intend to produce, stresses Hargis. Make sure you get answers to detailed questions about fulfilling a market contract. Don't leave the specifics up to the packer to decide at the time hogs are shipped.


Project the level of return, profit or loss you intend to receive for groups of pigs. Set a goal for a projected return on every pig that is sold out of the finishing barn.

“If you have a business plan where you want to make $5 a head on every pig you sell, you have to set that goal and stick to it,” says Hargis. “You can't be a speculator and wait out the market in hopes of a higher return.”

Table 1. SCMS Wean-to-Market Projections Example*
Input Data  
Feeder pig cost, head $78.00
Complete feed cost/ton $95.54
Grind/mix/delivery/ton $12.00
Delivered cost/ton $107.54
Meat price, cwt. $77.00
Meat basis $+or-/cwt. (Excel) ($4.50)
Meat premium, cwt. $0.00
Expected cut premium, cwt. $3.50
Vet, med, feed med., head $2.50
Market hog freight, head $3.00
Pig start weight, lb. 40
Market hog weight, lb. 270
Hot carcass weight, lb. 202.50
Expected average daily gain 1.70
Expected feed/gain, lb. 2.85
Feed/head, lb. 656
Days fill to fill, days 135
Throughput Data  
Barn turns/Year, turns 2.70
Expected death % 5.00%
Expected cull % 1.00%
Interest rate % 6.00%
Number of head 4,085
Total tons of feed 1,339
Total Expenses  
Death & cull cost/head $6.21
Interest cost/head $1.79
Feed cost/head $35.25
Vet, med/head $2.50
Market hog freight $3.00
Yardage/head (labor) $12.60
Management fee $0.50
Pork checkoff $0.69
Total cost/head $62.55
Revenue/market hog $153.90
Less cost/head $62.55
Purchase price $78.00
Return per head $13.35
*Numbers in red indicate “live” data.

For most owners, a $5-7 profit/hog long-term is a solid return. “If you can't make it on $5-7/hog, you need to either find an exit strategy or raise more pigs,” says Hargis.

Ninety percent of the producers on the SCMS wean-to-market program sell their hogs when prices hit a designated target price.

Declares Merna: “I keep hammering on these guys all the time. Let's take that $10-12/head profit so we don't have to make $20 a head on the next group to make up for failing to hit a home run.”

Refer to Table 1 for cost and revenue projections for feeding out pigs, and Table 2 for some marketing projections. Details are provided in the sidebar below.


Assemble your financial team to help set profit and loss figures. Include a banker, an accountant-tax person, production management consultant (such as SCMS), hog and grain brokers to provide marketing expertise, and a business consultant who can tie all of the production and financial information together, states Hargis.

A financial team will add about $1/head to your production costs. However, management expertise can help ensure that your cost and revenue projections ring true, he notes.

The financial team can help dispel many production fallacies that pork producers face. Pounds of pork produced per square foot of building space is often thought of as the ultimate barometer of pig efficiency. This legitimizes overcrowding.

But Hargis says when looking at cost control, net revenue per pig is king, and that is achieved by providing most finishers with 7.5 sq. ft./pig, not 7 sq. ft./pig.

A consistent, single pig flow or throughput can be the difference of a dollar or two of profit or loss on a pig, he says.

The percentage of optimal pigs sold at the packing plant generates more return for owners of finishing operations. The SCMS group averages about 94% optimal pigs sold feeder to finish.


Select who will care for the pigs. This is actually one of the most critical factors in a contract grower production system, stresses Hargis. He advises that when selecting a grower to follow up on references, interview prospective growers and review past production records and financial closeouts of past contracts.

“If a grower has a nice, isolated building and it's sitting empty, it's really important to find out why,” he observes.


Never buy pigs for feeding out without having every input cost locked up and targeting your market price.

“If you are putting pigs on feed, and you're not looking at what corn and meal and rent costs are going to be, and how much you are going to make, you are essentially saying, ‘I don't care whether I make money or not on these pigs,’” emphasizes Hargis.


Make sure someone from the management team (not the grower) sees those pigs once each week. When profit margins averaged $20/head, it was common for owners not to review grower performance until after a turn was completed. Today's slimmer margins require closer scrutiny.


Decide when pigs will physically be sold. Owners need to set the timeframe with their packer for actual delivery of the pigs. Trucks need to be lined up so the pigs can be sold on time and in the right weight range.

If there is a month's window for marketing, don't wait until the last week to nail down a delivery date, or you may be too late and the contract with the packer could be voided.

An automatic sorting system or a weigh scale can avoid costly weight errors.

Merna says not long ago, two producers each sold a semi-load of hogs on the same day, and both groups had cash bids of $62/cwt. At the plant, one group brought three cents under the base price, or $61.97/cwt., while the other group brought $65.01/cwt. The whole difference between the two groups was sort loss. One group weighed 268 lb., while the other group weighed 271 lb., just over the packer's weight limit of 270 lb. The producer with the sort loss didn't own a scale for weighing hogs.


Ensure each group sold has a production and financial closeout. The final results of marketings have to be on paper to know whether you hit your production numbers and price projections, points out Hargis.


Plan for an exit strategy if your business plan is not reaping financial rewards. “I call it an exit strategy, but it might not be an exit strategy out of the hog business,” says Hargis.

“For example, one producer who used to own barns and feed pigs for himself got into trouble because he was highly leveraged and failed at throughput. SCMS developed an exit strategy for him, and he became one of our best contract growers and oversees other contract sites for our management service company,” he says.

Hargis observes: “Our goal as a company is to keep producers from exiting the industry. We want to try to get them out of bad business plans, but keep good people in the pork business.”

SCMS is based in Wells, MN, and is affiliated with South Central Veterinary Associates.

Table 2. SCMS Marketing Projections Example*
Producer A
  Weight In 65 lb.        
  No. Head 4,085        
Date In   11/24/04 No. Head Barn Inventory Projected Sale Weight, lb. Average Weight, lb.
First Cut   3/4/05 416 3,669 280 277.5
2nd Cut   3/9/05 617 3,052 280  
3rd Cut   3/16/05 830 2,222 280  
4th Cut   3/23/05 1,164 1,058 270  
5th Cut   3/28/05 709 349 265  
Culls, head   3/23/05 106 243 200  
Deads, head     242 0 80  
      Group Average    
    Days to market   124  
    Weeks to market   17.71  
    Weight gain   212.5 lb.  
    Average daily gain   1.71 lb.  
    Yield   77%  
    Hot carcass weight   213.68 lb.  
    Mortality   5.93%  
*Does not guarantee performance. All numbers are projections based on industry standards. Producers need to evaluate all pigs based off of visual weight and age.

‘Real Time’ Worksheet, Tables Explained

Steve Hargis of South Central Management Associates (SCMS) has developed a “real-time” spreadsheet to track such things as feed usage, water usage and death loss on a weekly basis.

Data is collected automatically through sensors in the growers' barns that monitor water and feed consumption; the number of deads, culls, etc. are recorded manually by staff. For grower barns with automatic sorting equipment, pigs go through a scale and the information is uplinked directly to SCMS computers.

Data is sent by e-mail, voice mail or by Internet connection to SCMS. Hargis likes the regular submissions because it permits him to monitor performance of pigs as they grow to see if data meshes with cost and revenue projections.

“It shows you the actual feed you used and the pounds of feed budgeted and how many dollars spent vs. what's budgeted,” he explains.

Projecting Costs, Returns

As shown in Table 1, production costs highlighted in red are “live” figures. As they are adjusted, revenue projections automatically change.

“If I change average daily gain, it is going to change how much my barn costs are, and if I change feed conversion, it is going to change how much my feed costs are,” says Hargis.

“This can be a daily update to track your costs,” Hargis notes.

The projection sheet Hargis modified comes from a computer program developed by LeRoy, MN, pork producer Bob Baarsch, who uses it to operate several auto-sort barns at Next Generation Pork.

Pete Merna, logistics manager at SCMS, points out another unique feature of the projection sheet is that it includes deads, lights and culls as an actual cash expense.

This enables producers to pinpoint actual numbers of top hogs sold, adds Hargis, which is a key number in optimizing returns on a group closeout.

The worksheet is a very complete projection of all production expenses. It also includes deductions for pork checkoff and management fees (to SCMS or other consultants).

By closely estimating total costs, pig producers can come fairly close to knowing what they can afford to pay for weaner or feeder pigs to finish out, says Hargis.

Market Projections

A second sheet Hargis has developed projects marketing times. The example in Table 2 on page 31 depicts an incoming group of 65-lb. feeder pigs, estimated performance levels and five projected marketing cuts.

“If we are looking at controlling costs, and we want to make sure that we lock in a profit, then we better know what timeframe or selling period we need to sell these pigs on the Chicago Board of Trade,” he says.

For details, visit

Are We Controlling Mycoplasma?

Mycoplasmal pneumonia is commonly referred to as “enzootic pneumonia,” meaning that the disease is widespread and common among a population of animals.

There have been many estimates of prevalence within the U.S. swine industry, but most would agree that well over 90% of swine herds are positive for this organism.

The mycoplasma organism is a very small bacterium without a cell wall. It is a unique pathogen in that it does not invade the body, but instead colonizes the mucosal surfaces of the respiratory tract, destroying the surface cells (epithelium) and villi of the respiratory tract. This process makes the pig more susceptible to other bacterial pathogens such as Pasteurella multocida and allows viruses to replicate more easily.

In turn, the body does not mount an immune response in the same manner as when confronted with other bacterial pathogens.

The cell structure and the way it causes disease makes mycoplasma difficult to treat with many of the commonly used antibiotics.

Enzootic pneumonia, associated with mycoplasma and complicated with pasteurella, is likely the most costly swine respiratory disease.

Depending upon the prevalence and severity of the infection, this disease can reduce feed consumption and weight gain, resulting in reduced overall growth performance and increased treatment costs.

Previous studies have shown that vaccination against mycoplasma reduces the severity of lung lesions and clinical signs including coughing, which leads to improved feed efficiency and average daily weight gain during the finishing phase.

Even with effective vaccines, however, the producer must still pay special attention to stocking density, ventilation, biosecurity and control of other diseases to be successful in the long-term control of mycoplasma.

Health technologies such as all-in-all-out (AIAO) pig flows and multi-site production of nursery and grow-finish pigs have improved rate of gain and shortened days to market in the face of mycoplasma infection.

Case Study No. 1

A 2,000-sow, conventional health, commercial farm had a known problem with mycoplasma, which later turned into porcine respiratory disease complex (PRDC). The farm weaned at 2 to 3 weeks of age and for various reasons decided to vaccinate with a single-dose mycoplasma vaccine at weaning.

About 7-10 months after beginning this vaccination protocol, the farm was still experiencing a lot of morbidity and mortality from PRDC. Problems occurred late in finishing, often at about 18 weeks of age. While these “breaks” were no worse than before, they certainly were no better than prior to vaccination.

We reassessed the vaccination protocol and decided that while it was very convenient to vaccinate at weaning, it was just too early in this case. Also, perhaps for reasons of maternal antibodies, the pigs were just not developing protective immunity for mycoplasma throughout finishing.

Therefore, it was decided to shift the single-dose mycoplasma vaccine to about four weeks after weaning. Theoretically, this would allow enough time for the maternal antibodies to wane, while still allowing enough time to develop an active immunity to the vaccine before the challenge begins in the finishing phase. Time will tell if our strategy will be successful.

Case Study No. 2

A seedstock supplier was establishing a new, 500-sow nucleus herd and wanted to stock it with females from more than one source to assure the correct combination of genetic lines. The producer was concerned, since some of the potential sources were not free of mycoplasma.

The location for this new herd was very isolated. Since health was such an important component of future sales, it was decided to attempt disease elimination upon startup of this herd.

The various sources for the new farm were contacted to request that all of the animals targeted for this repopulation were within a two-month age window at the time of stocking. It was imperative to the producer that there be no animals under 10 months of age residing in the population at the time of the first farrowing on this new farm.

For added assurance of successful elimination of mycoplasma, all of the breeding animals (regardless of source and mycoplasma status) were given mycoplasma vaccine twice, once on arrival and again one month later.

Also, as the time approached for the first sows to farrow, the entire herd was medicated for two weeks with an antimicrobial known to be effective against mycoplasma.

By the time the first gilts farrowed, the youngest animal on the farm was at least 10 months old.

Now after almost four years, this farm is still producing mycoplasma-naïve seedstock.

Field Peas Show Potential

Field peas may soon allow Iowa grain producers to expand their crop rotation and provide Midwestern pork producers with a new source of home-grown amino acids.

Iowa State University (ISU) Extension Crop Specialist Jim Fawcett and ISU Extension Swine Specialist Tom Miller are currently studying the economic feasibility of growing field peas in southeast Iowa.

“We are trying to double-crop peas after a crop of wheat,” Miller explains. “We harvest the wheat crop around July 1, then come in and plant field peas.”

If all goes as planned, the peas should be done flowering by the end of September and be ripe before a killing frost. Miller believes the growing season is normally long enough, but weather conditions conspired against him in 2004.

“We didn't get them planted until the end of July, and then we were further slowed down by August temperatures that were 6.5 degrees below normal,” Miller adds. “They ended up getting nipped by an early killing frost Oct. 2. We chalked the year up to experience, but feel we could have raised decent peas if we could have gotten them in earlier.”

No New Equipment Needed

Yellow field pea seeds closely resemble soybean seeds when ripe. Peas can be grown using the same drills and harvesting equipment used for soybean production, so no additional equipment is needed.

Field pea acreage is increasing steadily in northern states like North Dakota and Minnesota. They tolerate very cold temperatures when young, but prefer cooler temperatures during flowering. In more southern zones, peas need to be planted either very early or in mid-July so the flowering period misses the heat of summer.

“If soil moisture is a concern with mid-summer plantings, the peas can be seeded up to three inches deep to place the seeds into moisture,” Miller says. “Inoculation of the seed is important for it to provide its own nitrogen.”

Broadening crop rotation has many agronomic benefits, but economic realities have forced farmers to concentrate on crops that offer the most returns, says Miller. He believes double-cropping wheat and peas will be a profitable option.

“Right now, the only crops we have left around here are corn and soybeans,” explains Miller. “That is going to come back and haunt us. Peas won't solve all the problems, but at least they will help. They also are a host to soybean cyst nematodes (SCN), but they won't build up a lot of SCN because they are harvested before SCN gets started.”

Good in Hog Rations

Peas are very good ingredients in hog rations. Phosphorus in field peas is highly digestible, thus reducing phosphorus excretion and the cost of the ration.

A 2003 South Dakota State University swine diet recommendation study by Bob Thaler and Hans Stein suggests that two parts corn and one part soybean meal can be replaced in a ration with three parts field peas. However, protein and energy concentrations vary between field pea varieties. Field peas are currently used as feed extensively throughout Australia, Canada and Europe.

On the Canadian prairies, where large quantities of peas are grown, they have become an important ingredient in hog rations. Big Sky Farms, a 29,000-sow, three-site, SEW (segregated early wean) farm based in Humboldt, Saskatchewan, feeds over 100,000 bu. of peas to hogs every month.

“Big Sky has been including peas in its ration since its inception in 1995,” explains Casey Smit, feed division manager at Big Sky Farms. “Peas are a good source of protein and amino acids such as lysine, and are very palatable in the diet. Most amino acids are supplied synthetically, but when we can supply them naturally through peas, it takes a lot of pressure off.”

Big Sky's ration currently uses feed wheat for its main energy source. Feed wheat is plentiful in Saskatchewan this year, following an early frost in August. The balance of the ration consists of barley, peas, soybean meal, canola meal, calcium, phosphorus, amino acids and canola oil or tallow.

“The Prairie Swine Centre (Saskatoon, Saskatchewan) has done research and found you could increase the level of peas to over 30% on a step-up program,” Smit says. “We currently max out at 25%, due to the availability of peas. The market is quite volatile at times and sometimes they are priced out of the diet. We need to be consistent in our diet, so we limit the amount of peas rather than putting them in and out of the diet.”

Peas vs. Soybeans

Big Sky uses a least-cost diet formulation. Whether peas are economical in this formula depends on their price relative to soybean meal. Since peas have less than half the available protein of soybean meal, they have to keep that spread to remain competitive. Usually, they are cost effective, although poor crops and heavy demand from the human food market has pushed them out of the hog market several times in the past few years.

Field peas are normally assigned a crude protein value of 23.4%. However, protein content can range from 15.5% to 39.7%, depending on the variety. This doesn't cause problems for Big Sky, however, as they purchase peas from a number of different suppliers and store them in one big bin. Nutrient tests are conducted on the entire bin before the peas are added to the ration.

“Peas are very palatable,” Smit says. “Unlike soybeans, they don't need to be processed before we feed them. They must be clean, though; we want 1% or less foreign matter. If you have something like mustard seeds in the feed, pigs will go off feed.”

ISU's Miller believes peas may have a place in Iowa, too. He is particularly excited by the possibility of adding peas to a blend of ethanol byproducts and corn.

“Peas let you pick up a lot of amino acids you were short on,” he theorizes. “It looks like a nice ration on paper, but we haven't done the field studies yet. We have to figure out how to grow these things down here first or we'd have to import them from further north. North Dakota pea producers average 40-50 bu./acre, and some studies in Illinois indicate they could get 40-50-bu. yields after wheat. Whether we can do that here on a yearly basis still remains to be seen.”

EPA Announces Landmark Air Emissions Agreement

The U.S. Environmental Protection Agency (EPA) has completed a major consent agreement with agriculture to study air emissions from livestock, poultry and egg production operations across the country.

The two-year benchmark study will be used to set national air policies, identify farm emission thresholds and then regulate excessive levels.

“National restrictions on air emissions will lower air emissions from livestock and poultry farms across the country,” says National Pork Producers Council (NPPC) President Keith Berry, Greencastle, IN, producer.

Before these policy changes can occur, both farmers and regulators need to understand how the air laws apply to farms of different sizes, design and location, according to Dave Roper, chairman of NPPC's Environment Committee.

“EPA officials in both the Clinton and Bush Administrations and scientists of the National Academy of Sciences agreed that sound scientific data was missing to enforce the current air laws,” adds Roper, Kimberly, ID, pork producer.

“We believe pretty firmly that there are a lot of areas in the country where there isn't an issue of air emissions at all,” he says. “With this study, these areas will be identified once and for all.” The second part of the agreement provides legal protection for past emissions if participating producers meet all the requirements of the agreement and fully comply with regulations that become established.

But Roper stresses this only applies to producers who sign the consent agreement and pay a small “penalty” fee that starts at $200, based on size and type of operation.

“All producers, whether they sign the agreement or not, will be subject to applicable permitting, emissions reporting and other compliance requirements once the data are analyzed and EPA publishes new national livestock air emissions standards,” says Roper.

University experts will conduct the EPA study. Purdue University will manage the study, oversee quality assurance, financial accounting and provide status reports to EPA, industry and the general public.

Pork producers interested in signing up should go to the EPA Web site to obtain a copy of the agreement:

7400 Series Tractors

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PRRS Testing for Boar Studs Revolutionized

A new blood test is quickly changing the way boar studs and possibly others test semen for porcine reproductive and respiratory syndrome (PRRS) virus.

While working on ways to increase the effectiveness of pooling semen samples to reduce the cost of PRRS testing, Minnesota swine veterinarian Darwin Reicks made a startling discovery.

He found that swine semen represents a poor model for early detection of the PRRS virus in boars.

“It was a real eye opener to me. I had 40 boars that we had infected six days earlier, and we only found two of them with semen PCR (polymerase chain reaction). It made me realize that with a typical boar stud doing statistical sampling, the odds are you are going to miss infection for a few weeks after it enters the boar stud. By the time you've figured it out, the boar stud could have already infected farms downstream,” he observes.

His research was supported by a grant from Boehringer Ingelheim Vetmedica, Inc.

PRRS Virus Infection

Initial PRRS virus infection moves slowly through a group of animals. When a boar stud first gets hit with PRRS, typically only a few animals are infected.

“The virus lays below the radar for several weeks before you really see any clinical signs. It spreads extremely slowly at first, before it builds up to a fairly high level in a few animals and spreads to others,” says Reicks, Swine Vet Center at St. Peter, MN. He coordinates swine health programs for a number of Midwest boar studs and consults internationally.

Finding A Better PRRS Test

The disappointing test results of finding PRRS in semen made it pretty clear to Reicks that a method of testing using blood had to be developed.

“Semen PCR is a very good test, but the problem is, unless you test every single ejaculate by individual semen PCR, by the time you pick up the virus in one boar, the odds are that other boars have already shed it in the semen,” he suggests.

Reicks also wanted to find a system that would be safer and faster than the standard serum collection procedure. That procedure calls for boars to be snared and a serum sample taken from the jugular vein, which is then sent to the lab to be spun down in a centrifuge and analyzed. It isn't practical to do this on a boar every week or twice a week, he explains.

In an experiment funded by Pork Checkoff, Reicks infected 20 boars with the PRRS virus and then tested them using semen, serum and a new blood swab test.

“Out of 60 samples, we had 59 of 60 samples test positive for PRRS with blood swab, and 60 out of 60 with serum. In only 27 out of 60 samples was PRRS virus detected in semen,” he points out.

And it took a lot longer for the virus to show up in semen than in serum.

The other issue with detection of the PRRS virus in semen is that the quantity of virus is so low, it barely registers on the PCR test in the early stages of an infection, says Reicks.

Plus, if you dilute or pool samples to cut testing costs, “you can basically just water it down to the point where the test won't pick up the virus anymore.”

In contrast, boars shedding virus in semen averaged 66 times more virus in blood swab tests than in semen, according to tests Reicks conducted last summer.

New Blood Swab Test

For the new blood swab test, while the boar is on the dummy being collected at the point of ejaculation, a very small needle is used to puncture one of the veins in the boar's ear, he explains. The blood drips out and it is wiped up with a swab, which is placed in saline solution, and the shaft containing swab and saline are submitted to the University of Minnesota Veterinary Diagnostic Laboratory for analysis.

Besides being safer than snaring a boar or collecting semen, it is also faster, remarks Reicks. To analyze its impact on the boar, flinch rates are measured. Flinch rate is whether the boar flicks its ear or not when it is poked with the needle.

“We found that there was typically about a 10% flinch rate, so we think collection time is a good, safe time for people to be sampling boars for PRRS,” he adds.

Blood swab samples received at the Minnesota diagnostic lab by noon can yield results by 7-8 p.m the same day. This means that a semen shipment only has to be held until later that night or early the next morning before it can be used with confidence, explains Reicks.

“But more importantly, the odds of detecting the virus sooner are so much better. You can more easily justify doing pooling of samples, because there is more virus in the blood early on than there is in the semen,” he stresses.

Studs Switch to New Test

Since mid-August, when Reicks first used blood swabs, all of the studs he works with have switched over to the new test.

“This has been a pretty big deal for the boar stud industry, and it may take another six months or so, but I don't think we'll have anyone doing semen PCR for PRRS testing anymore on the PRRS-negative studs,” he says.

Fast Test Results Saves Studs

In short, the blood swab normally detects infection within 24 hours of exposure when doing an individual PCR blood swab test, and results can be obtained within 12 hours.

Early detection of the PRRS virus can save boar studs from expensive depopulation.

Reicks observes: “We did that on a stud this past fall. We detected virus with the blood swabs and found there were three animals infected. We eliminated a circle of boars around them and were able to save the boar stud from depopulation.”

Reicks is working on refinements that would allow blood swab samples to be pooled and further improve the sensitivity of results.

Currently, it costs about a dollar per dose to do an individual blood swab PCR test on a boar.

The only justification for semen PCR testing for PRRS in the future will probably be in PRRS-positive boar studs that want to assure that semen they distribute is PRRS negative. Reicks says there are a few boar studs that maintain a PRRS-positive status because they don't feel they could stay negative if they depopulated.

Reicks says interest has been strong in learning more about the blood swab test. He will speak on its development at the American Association of Swine Veterinarians annual meeting in early March in Toronto, Canada.

Remarkable Advancement

The number of blood swab samples submitted to the University of Minnesota Veterinary Diagnostic Laboratory for testing of the porcine reproductive and respiratory syndrome (PRRS) virus is quickly rising, reports pathologist Kurt Rossow, DVM.

In 2004, only 6% of PRRS test samples were of the blood swab category, compared to 21% so far in 2005, he says.

“The blood swab method is safer, and you get a better sample as compared to semen,” explains Rossow.

PRRS virus shows up from a day to several days sooner in blood compared to semen, and in much greater quantities, he confirms.

Rossow notes the boar swab collection method is a “remarkable advancement in PRRS virus detection strategies and plays an important first step in the control and eventual eradication of this disease.”

Erysipelas-Mycoplasma Vaccine

Schering-Plough Animal Health Corporation introduces M+Rhusigen, a new vaccine with improvements for control of both erysipelas and Mycoplasmal pneumonia. M+Rhusigen is the industry's first vaccine to offer season-long efficacy, safety and protection against mortality due to erysipelas. In a controlled challenge study, 20 pigs were vaccinated twice intramuscularly at 3 weeks of age and again 21 days later and challenged with erysipelas. The vaccine afforded 87% protection against mortality from the disease. Vaccinated pigs also demonstrated significantly lower clinical signs of erysipelas. Protection is delivered via S-PX protein protective antigen, which provides protection throughout the growing cycle. The combination vaccine also contains M+Pac, Schering-Plough's field-proven Mycoplasmal pneumonia bacterin that protects up to six months.
(Circle Reply Card No. 102)

Farm Bureau Changes Sides on COOL

The American Farm Bureau Federation has formally ended its support for mandatory country-of-origin labeling (COOL) for red meat.

The change was due to some state Farm Bureau groups arguing consumers would buy U.S. meat if they could identify it, while others said the recordkeeping would be a burden on farmers.

The 2002 farm bill included a provision for mandatory COOL to go into effect Sept. 30, 2004. Congress delayed it until Sept. 30, 2006 on all products except seafood.