Study targets costly pig virus PRRS

Porcine reproductive and respiratory syndrome (PRRS), a fast mutating virus that affects pig herds and costs pork producers millions of pounds each year is being targeted by scientists. A transatlantic research group is tackling PRRS, which leads to reproductive failure in breeding stock and causes respiratory tract illness in young pigs.
Also known as Blue-Ear Pig Disease, the condition can prove fatal as it affects pigs’ immune systems and leaves them vulnerable to other infections.
Researchers at The Roslin Insitute, at the University of Edinburgh, are working with Iowa State University, which has received a $3 million grant, to find ways to tackle this devastating virus. They will study whether some pigs have a genetic makeup that makes them less likely to become sick following infections. This knowledge could help to ensure the breeding of healthier pigs, which are less likely to succumb to PRRS.
The virus is especially virulent as it evolves rapidly. As a result it now has many genetic variants. This causes challenges in vaccine production, as an inoculation against one strain does not protect against another strain of the virus. The research will include look at whether breeding for a specific gene variant, which protects against PRSS, does not have knock-on effects such as making the animal more vulnerable to another disease.
Although the exact economic impact of PRRSV has not yet been quantified in Europe, the virus is estimated to cost the United States pig industry around $600 million a year – almost a third of its losses related to infectious diseases.
Professor Steve Bishop, of The Roslin Institute said: “The constant mutation of the PRRS virus means that the efficacy of vaccines is severely hindered. This collaborative research project will enable us to assess the potential use of breeding to help reduce the impacts of this problematic disease.”
The $3 million grant to look into PRRS was awarded by the US Department of Agriculture’s National Institute of Food and Agriculture, while The Roslin Institute receives strategic funding from the Biotechnology and Biological Sciences Research Council.
Professor Jack Dekkers, from Iowa State University, said: “This grant is going to help us continue our work towards finding a way for the pork industry to get a handle on a costly and difficult-to-control disease, and we’re excited to move forward with our collaborators.”
Identifying gene variants that protect against infection can be a tricky process, and researchers have to be certain that breeding for a specific gene variant that makes pigs less susceptible to PRRS doesn’t have unintended consequences, such as making the animal more vulnerable to another disease. 

Pig study finds on-farm feed blending improves profitability

The results of a three-year trial confirm previous theories that altering pig diets more frequently than the standard industry practice can improve feed conversion and lower feed cost per pound of gain, according to Feedlogic Corp. 
The study demonstrates the value of blending feed on farm to more closely match the dietary requirements of pigs. The trial was conducted at a 1,200-head commercial hog finishing site in Minnesota and showed a net improvement in profitability of over $3.75 per marketed pig by blending feed versus feeding standard phase diets. The savings came primarily from a reduced feed cost per pound of gain. They also provide strong evidence that the blending does not come at the cost of carcass premiums.
More than 12,000 pigs were involved in the trial over a total of 10 turns. The trial facility was set up with a FeedSaver blending system which allowed half of the pigs (approx. 600 head) to be fed the standard phase diets and the other half to receive a blend of two standard diets – typically the first and fourth diets used in the standard phase program. 
Feed for both groups was weighed through the FeedSaver system, allowing an accurate comparison of feed consumption between the groups. The blended diets were changed with every 10 lbs/head of consumption; the phase diets as per the standard feed budgets.
Other standard protocols followed through the trial:
• All pigs placed at the same time and sorted evenly between pens (24 pens per group). The average weight of both groups was used as starting weight for all.

• Feed pricing was based on average delivered cost of diets for each turn.

• Both groups were fed an identical diet with Paylean (ractopamine) for the last 14 to 21 days of a turn, as per the standard procedure in the producer’s commercial system.

• Standard marketing procedures were followed – the largest pigs from either group were shipped first. Pigs from each group were tattooed separately to allow tracking of carcass data by group.
Key results from the trial:
• Feed conversion for the blend-fed group was 5% better than the control group (2.56:1 vs. 2.69:1).

• Blend-fed pigs averaged slightly better average daily gain (1.92 lbs vs. 1.89 lbs for the control group).

• Carcass yield, lean percentage, and backfat thickness were all virtually identical between groups.

• The average carcass premium per pig (which included sort loss) was $5.23 for the blend-fed group and $5.24 for the control group.

• Feed cost per pound of gain averaged $0.27 for the blend-fed group vs. $0.29 for the control group. 
Aside from improving pig producer profitability, the blending concept demonstrated in the trial also has benefit to feed mills since it reduces the number of diets that need to be manufactured and simplifies the feed delivery process. The same diet can be stored in a feed bin for a longer period of time, making it easier for truck drivers to manage. 

Iowa State University aims to improve swine dysentery diagnosis

Iowa State University veterinary researchers are working on developing improved methods for diagnosing swine dysentery, a disease which has re-emerged in recent years with increasing case numbers since 2003, according to the university.
The university veterinary diagnostic laboratory said it identified more than 100 cases in 2011, and 2012 seems to be tracking closely with those totals. Some possible causes for the re-emergence include changes in feeding practices that impact the intestinal microenvironment in pigs, changing genetics among herds or an emerging co-pathogen along with the bacteria that causes the disease, said Dr. Eric Burrough, an assistant professor in the Iowa State University Department of Veterinary Diagnostic and Production Animal Medicine.
Burrough also said the researchers have identified a newly emergent bacterial source which shares the genus of the classic swine dysentery bacteria but is not the same species. This new bacteria causes the same symptoms and is treated the same way, but the current tools used to identify swine dysentery can't detect it. “What we’re looking for is a more rapid diagnostic tool to identify both the classic bacteria and potentially novel strains that could cause swine dysentery,” said Burrough. “Until we find a method to screen for virulence with a faster turnaround, culturing will likely remain the most reliable means of confirming a diagnosis of this disease.”
Swine dysentery is preventable through biosecurity measures, said the researchers, whereas treating it can be a costly proposition. “The bottom line is you don’t want your herd to be contaminated, and you can’t afford it,” said Dr. James McKean, a university professor and associate director of the Iowa Pork Industry Center.

Low-protein pig diets could reduce nitrogen excretion

Feeding low-protein diets to pigs can reduce nitrogen excretion, according to research conducted by the University of Bristol and Scottish Agricultural College.
Three different diets were fed to finisher pigs of a lean genotype, between 40kg and 115kg, and pig growth and carcass quality were measured. A high-protein, standard commercial diet was compared with two low-protein diets: one (LP1) which reduced nitrogen intake by 11 percent while maintaining dietary amino acid levels, and the other (LP2) which reduced nitrogen intake by 16 percent but did not maintain essential amino acids in the later stages of growth.
Growth measurements showed that growth rate for pigs fed the LP1 diet was the same as the standard commercial diet, but feed conversion was slightly worse. “This was due to slightly greater fat deposition, especially within-muscle fat which creates marbling," said Professor Jeff Wood from the University of Bristol. "Growth rate was lower in LP2 pigs and they also became much fatter. Both LP1 and LP2 regimes would cost producers more than typical higher-protein diets at present because of the higher cost of fortifying the diets using amino acids and the poorer growth performance, especially with LP2.”
However, said Wood, tighter controls on nitrogen emissions in the future may mean pig producers will need to make use of this knowledge and alter feeding regimes. And, given the LP2 diet was shown to improve pork eating quality, greater incentives for quality would make this regime more attractive. It may also be possible to reduce nitrogen intakes even more in the future and lower the cost of these diets.

Enzyme supplements in pig feed may enhance feed conversion

Adding an enzyme supplement to a pig's corn-based diet may improve average daily gain, feed conversion and carcass quality, according to a study conducted by Adisseo. The company ran a Brazil study on pigs aged between 49 and 144 days, adding its own multi enzymatic product Rovabio Max to the pigs' feed.
In the experiment, the animals were split into three groups:

• Positive control: regular diet without enzyme
• Negative control: a diet decreased by 85 Kcal net energy/kg, 3% of protein and amino acids, 0.15% in available phosphorus and 0.10% calcium
• Negative control + Rovabio Max
According to the results of the tests, the average daily gain and feed conversion were significantly better for pigs receiving the negative control plus Rovabio Max, even when compared with the results of the positive group. Adisseo said that the trials, in addition to other studies, confirm the positive effect of enzyme supplements like Rovabio Max on gut morphology, microbiota and digestibility of the diets for growing and finishing pigs.

Some pigs may feed more efficiently, says study

Results of a preliminary experiment conducted at the University of Illinois indicate that it may be possible to select pigs that can make efficient use of energy in less expensive feed ingredients, thus reducing diet costs.
Less expensive feed is usually higher in fiber than the corn-soy diets typically used in U.S. swine production, according to Hans H. Stein, professor of animal sciences at the University of Illinois at Urbana-Champaign. However, the white breeds that are used in commercial pork production use only about 40 percent of the insoluble fiber. "If you can increase that number to 50 or 60 or 70 percent, then of course, you would get a much better use of the energy in those ingredients," said Stein. "There are also indigenous breeds of pigs that have not been selected for commercial production, and these breeds have, therefore, not been fed the corn-soybean meal diets for as many generations as the white breeds."
The study focused specifically on Chinese Meishan pigs, on the theory that they would use fiber more efficiently than the typical white breeds. "What we observed was that, particularly for the DDGS diets, the Meishans were quite a bit more effective at using that fiber," said Stein. "That diet is high in insoluble dietary fiber. When we looked at more soluble fibers, there was no difference." Although Meishan pigs would never be used for commercial pork production in the U.S., the results indicate that differences exist among breeds of pigs. Thus, it is possible that differences also exist among the white breeds and that some may use fibers more efficiently than others, according to the researchers.
Stein said that the findings are preliminary, and determining if white breeds can be bred to use insoluble fiber more efficiently will be expensive because it requires selecting pigs for multiple generations. The next step is pursuing funding for further research.

Pig gait study could help reduce lameness

Ph.D. student Sophia Stavrakakis works with a pig test subject.

A Newcastle University study is using the way a pig walks to help determine whether it could be prone to lameness later in life, according to researchers.
Using video motion capture, researchers at the UK-based university measured changes in the pigs’ gait, focusing on the angle of the joints and length of stride. By assessing what constitutes a "normal" gait in pigs, the team determined how the system could be used to reduce lameness, improving health and welfare on farms, reducing costs and improving sustainability. “Lameness among livestock is a major problem for farmers,” said Ph.D. student Sophia Stavrakakis. “Female breeding pigs are particularly prone to leg problems and this makes it costly for farmers when an animal becomes lame because of the time and money invested in the breeding stock. Using biomechanical motion capture we are able to measure the animals’ gait — tracking a number of animals to find the right angulation and locomotion. Through this we hope to be able to develop a farmer-friendly system that will allow them to identify those pigs with better legs, a trait that can be passed on to subsequent generations.”
As part of the study, the pigs were trained to walk along a runway. Once the pigs had learned to walk at the right speed, the researchers attached reflective markers at key points on the pigs' legs and used motion-capture cameras to track their movements and identify those parameters which can indicate a good pig. The results provided an initial benchmark against which other pigs can be assessed. “Making sure the pigs all walked at the same pace was crucial, because otherwise you can’t accurately compare leg movement and angles,” said Dr. Jonathan Guy, a lecturer in animal science and project supervisor.
The aim now, according to Stavrakakis, will be to adapt the system so it can be used on farms to improve pig welfare. “The work is still in its early stages, but the aim is to use our research to make a real difference to both pig farmers and their animals,” said Stavrakakis. “Using CCTV-style cameras placed strategically on the farm so that every pig walks past and is captured on camera would be a simple, non-invasive way of collating key data about each pig and identifying those animals which are least likely to suffer problems in the future.”

Pig industry professionals study global demand, profitability at Alltech seminar

A recent Alltech Pig Solutions Seminar focused on performance versus profit as pig industry professionals looked at global population growth, a change in demand and the challenges of meeting that demand while continuing to do business.
“A change of focus is required,” said Patrick Charlton, Alltech’s European regional director. “Seventy percent of the growth in global meat demand will come from Asia. Who will produce this meat? Europe has held its ground in terms of technical development and ability, but Brazil and the U.S. continue to have the lowest cost of production. It’s time for all regions to find the performance-profit balance to be able to provide for this new population dynamic and keep pork as the number one global animal protein.”
Of the 110 industry professionals surveyed at the seminar:

• 80% believe that 30 pigs weaned per sow per year is realistic.
• Opinions were divided over whether the carbon footprint of pork will become increasingly important over the next decade, with 69% agreeing that it will be increasingly important and 20% disagreeing.
• 88% of attendees agree that managing herd health is one of the industry’s biggest challenges.
• In terms of programmed nutrition and metabolic imprinting, 23% think that it will impact greatly on feed efficiency alone and 44% think that it will impact greatly on feed efficiency, pig health and product quality.
• Attendees were divided again on the issue of feed costs, with 57% agreeing that low feed costs are a thing of the past and 35% disagreeing with this statement.
• 35% think that the recent contamination scares in China will result in more stringent regulations enforced on feed suppliers, animal producers and processors.
• 29.5% also think that the contamination scare will make consumers more aware of potential contaminants within the food chain.

Swine researchers find UV light may inactivate PRRS virus

According to researchers at the University of Minnesota College of Veterinary Medicine's Swine Disease Eradication Center, ultraviolet light may have the ability to inactivate the porcine reproductive and respiratory syndrome virus.
Ultraviolet light is already known for neutralizing viruses, bacteria and parasites by disrupting the nucleic acid and preventing replication. The study focused on the concentration and viability of PRRSV on surfaces and materials commonly encountered on swine farms, including wood, plastic, latex, rubber, styrofoam, metal, leather, cloth, concrete, cardboard, glass and paper.
The researchers' results suggest that UV(254) is an effective means to inactivate PRRSV on commonly encountered farm surfaces and materials and inactivation can be accomplished following 10 minutes of exposure.

PCV2 virus study gives UK pig producers insight into porcine reproductive failure

Britain’s Veterinary Laboratories Agency, VLA, is to increase surveillance for PCV2 virus as a cause of reproductive failure in cases of abortion and stillbirth, where no other infectious cause has been identified.
The hearts of stillborn or aborted piglets submitted to the agency will be examined for myocarditis, the lesion caused by PCV2 in the heart of the developing pig foetus. When a myocarditis is detected, immunohistochemistry will be used to determine whether PCV2 is the cause.
VLA veterinary officer Susanna Williamson says: “Data from the field and research show that PCV2 can be transmitted to the pig foetus, and may, in previously naïve gilts and sows, cause piglets to be aborted or stillborn with myocarditis lesions. "Through this increased surveillance we will be able to monitor for PCV2-associated abortion and stillbirth and obtain a better idea of the role that it plays in porcine reproductive failure in England and Wales. Other pathogens may also cause myocarditis, which is why it will be essential to demonstrate the PCV2 in association with lesions to obtain a diagnosis.”
Ricardo Neto, veterinary advisor with Merial Animal Health, said: “We welcome this move as it should provide a clearer picture about what is happening with regard to the transmission of the PCV2 virus and the effect that it has.
“It would be very helpful if vets could have a diagnosis of PCV2 in reproductive failures on their client farms, especially because the control of PCV2 among breeding animals can have such a great economic impact.”

Kenyan pig farmers try to curb epilepsy parasite

The American Journal of Tropical Medicine and Hygiene has released results of an education program aimed at teaching pig farmers to tether their animals, inspect pork, and treat sick pigs. This may help stop pigs from spreading a tapeworm that infects humans and causes epilepsy in poor countries, such as Africa, Asia, and Latin America, according to an article in the New York Times.
People come in contact with the parasite, Taenia solium from undercooked pork or from food contaminated by feces from a person infected with the disease. The parasite’s eggs are passed in feces and infect pigs that come in contact with human waste. If the eggs are ingested by a person, a larval form of the worm can infect the brain and cause seizures, says the New York Times.