USDA

16 New Lettuce Breeding Lines from ARS

USDA Agricultural Research Service - Thu, 05/14/2015 - 06:56
16 New Lettuce Breeding Lines from ARS / May 14, 2015 / News from the USDA Agricultural Research Service

Read the magazine story to find out more.

 A Romaine lettuce line with resistance to dieback, which is caused by soilborne viruses. Link to photo information
ARS researchers have developed and released 16 new lettuce breeding lines, including 6 icebergs, 6 leaf lettuces and 4 romaine varieties with traits such as better disease or pest resistance or other consumer-oriented trait. Click the image for more information about it.



For further reading

16 New Lettuce Breeding Lines from ARS

By Sharon Durham
May 14, 2015

U.S. Department of Agriculture (USDA) scientists in California have developed 16 new lettuce breeding lines. Lettuce production in the United States is concentrated mostly in California and Arizona, where it is grown year-round. Salinas, California, in fact, is often referred to as “the salad bowl of the nation.”

In field, greenhouse and laboratory experiments, Agricultural Research Service (ARS) plant geneticists Ivan Simko, Ryan Hayes, and Beiquan Mou, and plant pathologist Carolee T. Bull, all in the Crop Improvement and Protection Research Unit in Salinas, California, developed and tested the performance and resistance of the new lettuce breeding lines. These lines, now available to plant breeders, include 6 icebergs, 4 romaines, and 6 leaf lettuces. The Salinas researchers collaborated with Yaguang (Sunny) Luo, a research food technologist at the Food Quality Laboratory in Beltsville, Maryland, for testing of the lines, including postharvest evaluations of lettuce quality; size and shape of the heads; size, shape, and texture of the leaves; and core length.

ARS is the U.S. Department of Agriculture’s chief intramural scientific research agency.

The research group’s goal is to develop and release lettuce lines with combined resistance to pests and diseases and with as many different traits as possible that are advantageous to producers and consumers. Of the six iceberg lettuce lines, five are suitable for salad-blend and whole-head markets, according to Simko. The one iceberg line not suitable for these markets can instead be used in breeding programs as a donor of genes for resistance to downy mildew, bacterial leaf spot and Verticillium wilt.

According to Simko, two of the romaine lettuce lines are appropriate for salad-blend, spring-mix and whole-head production. One of the other lines can’t be used for fresh-cut products because it decays rapidly after processing, but it is suitable for the whole-head market. Each of these three breeding lines has resistance to dieback, a plant disease to which most of the currently grown romaine cultivars are susceptible.

Each of the six leaf-lettuce breeding lines is acceptable for commercial production as a salad blend or spring mix. Three could also be used for whole-plant production, and two lines demonstrated very high field resistance to downy mildew, according to Simko.

This research was also supported by the California Leafy Greens Research Program and the California Department of Food and Agriculture Specialty Crop Block Grant Program.

Limited samples of the lettuce seeds are available for distribution to those interested in conducting research or commercial production.

Categories: USDA

Bee Survey: Lower Winter Losses, Higher Summer Losses, Increased Total Annual Losses

USDA Agricultural Research Service - Wed, 05/13/2015 - 09:20
Bee Survey: Lower Winter Losses, Higher Summer Losses, Increased Total Annual Losses / May 13, 2015 / News from the USDA Agricultural Research Service

Honey bee on an apple blossom.
Winter losses of managed bee colonies are down slightly, but summer losses have risen, resulting in higher overall annual losses of managed bee colonies. Click the image for more information about it.

Graph depicting winter and annual honey bee losses from 2006 to 2014Credit: Bee Informed Partnership/University of Maryland/Loretta Kuo
ARS-USDA Information Staff.


For further reading

Bee Survey: Lower Winter Losses, Higher Summer Losses, Increased Total Annual Losses

By Kim Kaplan
May 13, 2015

WASHINGTON, May 13, 2015 — Losses of managed honey bee colonies were 23.1 percent for the 2014-2015 winter but summer losses exceeded winter numbers for the first time, making annual losses for the year 42.1 percent, according to preliminary results of the annual survey conducted by the Bee Informed Partnership (http://beeinformed.org), the U.S. Department of Agriculture (USDA) and the Apiary Inspectors of America.

The winter loss improvement was about 0.6 percentage points less than the losses reported for the 2013-2014 winter. This is the second year in a row that winter losses have been noticeably lower than the nine year average winter loss of 28.7 percent.

However, beekeepers are not losing colonies only in the winter but also throughout the summer, sometimes at significant levels. Summer losses for 2014 were reported as 27.4 percent, exceeding 2014-2015 winter losses for the first time. In previous years, 2013 summer losses were reported as 19.8 percent compared to 23.7 percent for 2013-2014 winter losses, and 2012 summer losses were reported as 25.3 percent compared to 30.5 percent for 2012-2013 winter losses. Winter losses were considered October 2014 through April 2015.

Total annual losses were 42.1 percent for April 2014 through April 2015.  The new figure is up from 34.2 percent for 2013-2014.

"The winter loss numbers are more hopeful especially combined with the fact that we have not seen much sign of Colony Collapse Disorder (CCD) for several years, but such high colony losses in the summer and year-round remain very troubling," said Jeff Pettis, a survey co-author and a senior entomologist at USDA’s Agricultural Research Service Bee Research Laboratory in Beltsville, Maryland. “If beekeepers are going to meet the growing demand for pollination services, researchers need to find better answers to the host of stresses that lead to both winter and summer colony losses.”

About two-thirds of the beekeepers responding to the survey reported losses greater than the 18.7 percent level that beekeepers reported is economically acceptable. This underlines the seriousness of the health problems stressing honey bees in this country, Pettis pointed out.

“We traditionally thought of winter losses as a more important indicator of health, because surviving the cold winter months is a crucial test for any bee colony,” said Dennis vanEngelsdorp, an assistant professor of entomology at the University of Maryland and project director for the Bee Informed Partnership. “But we now know that summer loss rates are significant too. This is especially so for commercial beekeepers, who are now losing more colonies in the summertime compared to the winter. Years ago, this was unheard of.”

Backyard beekeepers were more prone to heavy mite infestations, but we believe that is because a majority of them are not taking appropriate steps to control mites,” vanEngelsdorp said. “Commercial keepers were particularly prone to summer losses. But they typically take more aggressive action against Varroa mites, so there must be other factors at play.”

For these preliminary survey results, more than 6,100 beekeepers across the country who managed almost 400,000 colonies in October 2014, representing nearly 15.5 percent of the country's 2.74 million colonies, responded to the survey.

A loss of 23.7 percent of managed honey bee colonies was reported for the 2013-2014 winter and 30.5 percent loss for the winter of 2012-2013. Previous surveys found winter losses of 21.9 percent in 2011-2012, 30 percent in 2010-2011, 33.8 percent in 2009-2010, about 29 percent in 2008-2009, about 36 percent in 2007-2008, and about 32 percent in 2006-2007. Annual colonies losses were 34.2 percent for 2013-14, 45 percent for 2012-2013, 28.9 percent for 2011-2012, and 36.4 percent for 2010-2011.

This survey was largely supported by a grant from USDA's National Institute of Food and Agriculture, which also provides the majority of funding for the Bee Informed Partnership.

A complete analysis of the survey data will be published later this year. The abstract for the analysis is at http://beeinformed.org/results-categories/winter-loss-2014-2015/.

More information about ARS honey bee health research and CCD can be found at www.ars.usda.gov/ccd.

Categories: USDA

New Begonia Lines both Beautiful and Sturdy

USDA Agricultural Research Service - Tue, 05/12/2015 - 07:29
New Begonia Lines both Beautiful and Sturdy / May 12, 2015 / News from the USDA Agricultural Research Service

Read the magazine story to find out more.

 ARS geneticists Hamidou Sakhanokho (left) and Cecil Pounders review two newly co-developed begonia lines. Link to photo information
ARS geneticists Hamidou Sakhanokho (left) and Cecil Pounders have released two germplasm lines for use in breeding new begonia varieties that can tolerate the heat and humidity of a Gulf Coast summer. Click the image for more information about it.



For further reading

New Begonia Lines both Beautiful and Sturdy

By Jan Suszkiw
May 12, 2015

Two new begonia germplasm lines developed by U.S. Department of Agriculture (USDA) scientists and their collaborators are now available for use in breeding elite varieties of the ornamental crop that can tolerate the heat and humidity of a Gulf Coast summer.

Begonia semperflorens is the most widely cultivated type of begonia and fourth most popular bedding plant in the United States, generating $36 million in sales (in 2009). However, in Gulf Coast states like Mississippi, Georgia, Alabama and Florida, the onset of summer can overwhelm these popular flowering perennials with intense heat and humidity, cutting short the plants’ colorful presence in flowerbeds, hanging baskets and containers.

The new germplasm lines, labeled FB08-59 and FB08-163, were officially released in September 2014 as a source of genetic material that plant breeders can transfer better into commercial varieties for improved heat tolerance. Cecil Pounders, a retired plant geneticist with USDA’s Agricultural Research Service (ARS) in Poplarville, Mississippi, collaborated on the begonia releases with fellow ARS plant geneticist Hamidou Sakhanokho and colleague Leopold Nyochembeng of Alabama A&M University.

The team used a conventional plant-breeding technique called “recurrent selection” to develop the two germplasm lines. FB08-59 is the “top pick” of several generations of offspring plants that were evaluated after crosses between the commercial begonia Kaylen and B. cucullata var. arenosicola, an herbaceous South American species. FB08-163 was selected from a cross between Kaylen and the commercial begonia Shanzi.

FB08-59 and FB08-163 grow to heights of about 12 and 20 inches, respectively. Their dark, waxy leaves encircle purple-red flowers with white specks in the petals and yellow stamens in their centers.

In trials, Vodka, Whisky, Gin, Senator, Inferno Red, Bada Bing Red and Bada Boom Scarlet—varieties commonly planted in the South—fared poorly when grown under the same test conditions as FB08-59 and FB08-163, succumbing to a combination of heat stress and Pythium fungal infections, the team reported in the January 2015 issue of HortScience.

Read more about the begonia lines in the May 2015 issue of AgResearch magazine. ARS is USDA’s principal intramural scientific research agency.

Categories: USDA

Recipe for Flavorful Tomatoes: Heat Before Chilling

USDA Agricultural Research Service - Thu, 05/07/2015 - 07:01
Recipe for Flavorful Tomatoes: Heat Before Chilling / May 7, 2015 / News from the USDA Agricultural Research Service

Read the magazine story to find out more.

 Ripe tomatoes on the vine.  Link to photo information
Briefly heating tomatoes in warm water before chilling them for shipping or storing can help improve their taste, according to new research from ARS chemist Jinhe Bai. Click the image for more information about it.


For further reading

Recipe for Flavorful Tomatoes: Heat Before Chilling

By Dennis O'Brien
May 7, 2015

A U.S. Department of Agriculture (USDA) chemist in Florida has found a way to help tomato producers improve the taste of their tomatoes. The process is simple—just immerse them briefly in warm water to heat them.

Tomatoes are often picked green and then stored at low temperatures during and after transport to slow ripening. They are then ripened at about 68 °F before being placed on store shelves. That process makes them easier to ship and extends their shelf life. Jinhe Bai, who is with the USDA’s Agricultural Research Service (ARS) in Fort Pierce, wondered if the chilling was why “supermarket tomatoes” often taste bland. ARS is USDA’s chief intramural scientific research agency.

Bai and his colleagues harvested 120 standard “Florida 47” variety tomatoes and subjected 30 tomatoes each to one of four treatments: applying heat only, chilling (to the industry standard of 41 °F), heating prior to chilling, and keeping them at room temperature (controls). For the heat treatment, the tomatoes were placed in 125 °F water for 5 minutes. Like commercially produced tomatoes, tomatoes in the study were ripened at 68 °F after being exposed to the temperature treatments.

Samples of each group were cut and placed into sealed containers. The containers were opened less than an hour later, and the tomatoes were rated for flavor by 21 volunteers, based on the aromas released. The study was designed to evaluate fruit aroma so only the odors were assessed to eliminate bias from taste and “mouth feel.” The researchers also used gas chromatography-mass spectrometry to identify levels of 12 key volatile aroma compounds known to give tomatoes their flavor.

The results show that applying the heat treatment to mature green tomatoes, before they are chilled and shipped, stemmed the loss of several flavor volatiles known to give fruity and floral scents to foods as diverse as citrus and saffron. The heated-then-chilled tomatoes also had more flavor volatiles than the tomatoes that were only chilled: 14 out of 21 panelists could detect more tomato aroma.

It doesn’t help to heat and chill a ripe tomato purchased off a store shelf, Bai says. The heating and chilling process should be applied when the tomatoes are still green. But the treatment does benefit tomatoes that are first beginning to turn red, which is known as their “breaker stage.” The study was published online in LWT-Food Science Technology in January 2015.

Read more about this research in the May 2015 issue of AgResearch magazine.

Categories: USDA

Newly Named Bacteria Help Honey Bee Larvae Thrive

USDA Agricultural Research Service - Wed, 05/06/2015 - 06:06
Newly Named Bacteria Help Honey Bee Larvae Thrive / May 6, 2015 / News from the USDA Agricultural Research Service

Read the magazine story to find out more.

 Honey bee larvae in artificial cells on the right; capped artificial cells on the left where larvae become pupae. Link to photo information
ARS scientists have recently found new species of bacteria that appears to help honey bee larvae survive better, in laboratory studies. Click the image for more information about it.


For further reading

Newly Named Bacteria Help Honey Bee Larvae Thrive

By Kim Kaplan
May 6, 2015

U.S. Department of Agriculture (USDA) scientists have identified a bacterium that appears to give honey bee larvae a better chance of surviving to become pupae.

Molecular biologist Vanessa Corby-Harris and microbial ecologist Kirk E. Anderson at the Carl Hayden Bee Research Center in Tucson, Arizona, have named the new species Parasaccharibacter apium. The bee research center is part of the Agricultural Research Service, USDA’s chief intramural scientific research agency.

Honey bees have been under nearly constant and growing pressures from a whole host of stressors—diseases, poor nutrition, sublethal effects of pesticides and many others, especially for the last 30 years. It has been known that a number of different bacteria live within adult bees and in the hive, and scientists have been studying if and how these bacteria help deal with some of these stresses.

This is the first bacteria found to offer a benefit to bee larvae. In laboratory experiments, bee larvae fed P. apium had about an average of 30 percent better survival compared to those fed a sterile control.

How P. apium confers this survival advantage to the larvae is not yet known, according to Corby-Harris.

So far, the researchers have found P. apium only in honey bees and their hives. While P. apium found in honey bee hives is a distinct and new species from any previously identified, it has very close, naturally occurring relatives found in the nectar of many flowers, including cactus flowers, daisies, thistles and apple blossoms.

The genome of P. apium has been sequenced and they are beginning to dissect the functional properties that distinguish flower-living Acetobacteraceaefrom those that have coevolved with the honey bee hive. Pinpointing these ecological differences will be key to understanding the function of P. apium in honey bee hives, Anderson explained.

With minimal sampling effort, P. apium was found in nearly every one of the healthy managed bee colonies examined by the researchers. A future study will explore the abundance of P. apium in weak or struggling managed bee colonies.

While the mechanism by which the bacteria benefit the larvae remains to be studied, the importance is clear enough that Corby-Harris and Anderson are already field testing its use along with a number of other bacteria that may benefit the pollination and honey-production industry as potential management tools.

Read more about this research in the May 2015 issue of AgResearch magazine.

Categories: USDA

New Fruit Fly Lure Developed from Pests Favorite Scent

USDA Agricultural Research Service - Wed, 04/29/2015 - 07:38
New Fruit Fly Lure Developed from Pest’s Favorite Scent / April 29, 2015 / News from the USDA Agricultural Research Service
Read the magazine story to find out more.

 A melon fruit fly on a squash. Link to photo information
A new lure developed by ARS scientists based on cucumber aromas may help provide better control of melon fruit flies, one of four non-native fruit fly species that cost Hawaii's fruit and vegetable growers up to $15 million in losses annually and threatens the mainland United States. Click the image for more information about it.


For further reading

New Fruit Fly Lure Developed from Pest’s Favorite Scent

By Jan Suszkiw
April 29, 2015

Ongoing development and testing of a new melon fruit fly lure derived from cucumbers may lead to improved monitoring and control of this costly agricultural pest. That’s the goal of U.S. Department of Agriculture (USDA) scientists who developed the lure in studies at the USDA Agricultural Research Service’s Tropical Crop and Commodity Protection Research Unit in Hilo, Hawaii.

In Hawaii, the melon fly, Bactrocera cucurbitae, is one of four non-native tephritid fruit fly species that cause up to $15 million annually in direct losses to the state’s fruit and vegetable crops. B. cucurbitae is also considered a quarantine pest in the mainland United States and inflicts significant agricultural losses in other regions of the world.

The use of attractants to monitor adult fly numbers and movements plays a critical role in Hawaiian growers’ implementation of area-wide approaches to manage the 6- to 8-millimeter-long pest. These tactics include sanitation measures like destroying infested fruit and using trap crops.

Currently, two types of products are used: liquid protein baits and male-only lures. However, more accurate monitoring and better population control can be achieved if female flies can also be attracted, says entomologist Eric Jang, who leads the Hilo research unit.

In studies there, Jang and colleagues used a procedure called “gas-chromatograph electro-antennogram analysis” to measure how strongly melon flies responded to different blends of 31 volatile compounds emitted from freshly puréed cucumber, among the pest’s favorite hosts. From this analysis, they initially identified and tested a nine-compound blend that proved attractive to female flies but later focused on a seven-compound blend that worked even better when formulated as a dry bait.

During outdoor trials in Hawaiian papaya fields and in Taiwan with sponge gourd, 100 milligrams of the dried synthetic cucumber blend captured more melon fruit flies than both the protein bait and male-only lures. The blend also lasted as long as the other two products when the dosage was increased to 300 milligrams.

Read more about the lure in the April 2015 issue of AgResearch magazine. ARS is USDA’s chief intramural scientific research agency.

Categories: USDA

New Issue of Healthy Animals Now Online

USDA Agricultural Research Service - Tue, 04/28/2015 - 12:21
New Issue of Healthy Animals Now Online / April 28, 2015 / News from the USDA Agricultural Research Service

 Healthy Animals icon. Link to latest issue.
Click the image for latest issue.

New Issue of Healthy Animals Now Online

By Sandra Avant
April 28, 2015

The Agricultural Research Service (ARS) today posted a new issue of Healthy Animals. This semi-annual online newsletter compiles ARS news and expert resources on the health and well-being of agricultural livestock, poultry and fish.

Twice a year, one article in Healthy Animals focuses on a particular element of ARS animal research. The current issue focuses on improving Newcastle disease vaccines and more stringent methods to evaluate them.

Other research highlighted in this issue includes:

  • Swatting Stable Flies: ARS scientists are trapping stable flies that are pestering zoo animals.
  • Canine Bug Detectors: Dogs are being used to sniff out stink bugs indoors and outdoors.
  • Goodbye Fish Egg Fungus: A compound used to disinfect wastewater and sterilize items for hospitals and the food industry can kill fungus on catfish eggs.

Professionals interested in animal health issues might want to bookmark the site as a resource for locating animal health experts. An index lists ARS research locations covering 70 animal health topics. These range from specific diseases, such as Lyme disease, to broad subjects such as nutrition or parasites.

The site also provides complete contact information for the 25 ARS research groups that conduct studies aimed at protecting and improving farm animal health.

To receive an e-mail alert about each issue's online posting, contact Sandra Avant, ARS Information Staff, or sign up online.

ARS is the principal intramural scientific research agency of the U.S. Department of Agriculture.

Categories: USDA

New Berries from ARS

USDA Agricultural Research Service - Wed, 04/22/2015 - 07:01
New Berries from ARS / April 22, 2015 / News from the USDA Agricultural Research Service

 Two ripe red and two immature strawberries on the vine of Sweet Sunrise, an ARS cultivar. Link to photo information
Sweet Sunrise strawberry is new high-yielding, June-bearing cultivar from the ARS breeding program in Corvallis, Oregon. Click the image for more information about it.


For further reading

New Berries from ARS

By Sharon Durham
April 22, 2015

Two new berries have been developed thanks to U.S. Department of Agriculture (USDA) scientists at the Horticultural Crops Research Unit in Corvallis, Oregon, and their collaborators.

Berries of all types are wonderful additions to a healthy diet, providing nutrients, fiber and flavor. Sweet Sunrise (U.S. PP 25,223) is a new strawberry cultivar from the Corvallis breeding program, which is led by Agricultural Research Service (ARS) plant geneticist Chad Finn. This strawberry was released in cooperation with the Oregon Agricultural Experiment Station (OAES) and Washington State University’s Agricultural Research Center.

ARS is the USDA’s chief intramural scientific research agency.

Sweet Sunrise is a high-yielding cultivar that ripens in June. It produces large, firm attractive fruit having excellent quality. According to Finn, Sweet Sunrise was high-yielding in every trial and location. Yields are comparable to, or higher than, those of other recent releases such as Charm, Valley Red, and Sweet Bliss or the industry standards Tillamook, Totem, and Hood. In all evaluations, Sweet Sunrise was rated excellent and comparable to Totem for commercial processors.

Finn also developed Columbia Star (U.S. patent applied for), a thornless, trailing blackberry cultivar from the same breeding program as Sweet Sunrise. Columbia Star was released in 2013 in cooperation with OAES.

The new blackberry is a high-quality, high-yielding, machine-harvestable blackberry with firm, sweet fruit that when processed is similar in quality to, or better than, fruit from the industry standards Marion and Black Diamond.

Both of these new berry cultivars will be good additions to the fresh- and processed-fruit markets, according to Finn.

Read more about this research in the April issue of AgResearch magazine.

Categories: USDA

USDA Scientists, International Colleagues Sequence Upland Cotton Genome

USDA Agricultural Research Service - Tue, 04/21/2015 - 12:03
USDA Scientists, International Colleagues Sequence Upland Cotton Genome / April 21, 2015 / News from the USDA Agricultural Research Service

 Upland cotton boll.
ARS scientists and their partners have sequenced the genome of Texas Marker-1, the genetic standard for upland cotton, the world's most widely cultivated and genetically complex species of Gossypium. Photo courtesy of Russell Kohel, ARS (retired).


For further reading

USDA Scientists, International Colleagues Sequence Upland Cotton Genome

By Dennis O'Brien
April 21, 2015

Resulting "roadmap" could help improve yields, fiber quality and plant resilience

WASHINGTON, April 21, 2015U.S. Department of Agriculture (USDA) scientists and their partners have sequenced the genome of the world's most widely cultivated and genetically complex species of cotton, a milestone that will make it easier to address increasing threats to cotton by tapping into its natural defenses. The results were published today in two Nature Biotechnology reports.

Sequencing the genome of Upland cotton (Gossypium hirsutum) will help breeders develop varieties of cotton that are better equipped to combat the pests, diseases and higher temperatures and droughts expected to accompany climate change. Cotton growers have experienced a plateau in yields since the early 1990s, and most commercial varieties lack genetic diversity, making cotton vulnerable to natural threats. The findings will help researchers and breeders in the years ahead develop cotton varieties with improved fiber qualities, higher yields and more tolerance to heat, drought and diseases anticipated due to climate change. Cotton is grown on 12 million acres in 17 states and is a $6 billion crop in the United States.

"There is a vast, untapped reservoir of genes in wild cotton plants that could offer us stronger and more effective defenses to the numerous challenges faced by cotton growers. Sequencing of a genetic standard in cotton gives us the roadmap to identify and tap into that reservoir of genetic variability," said Chavonda Jacobs-Young, administrator of the USDA's Agricultural Research Service (ARS). ARS is USDA's principal intramural scientific research agency.

The studies are the result of nearly a decade of international collaboration. ARS scientists Richard Percy and Russell Kohel (retired) are coauthors and John Yu is corresponding author of one publication. They are based in College Station, Texas. ARS scientist Brian Scheffler, based in Stoneville, Mississippi, is a coauthor of the other. The two teams sequenced the genome of the genetic standard of Upland cotton, Texas Marker-1, which is often used in studies and in developing new genetic lines.

Upland cotton is the result of millions of years of evolution and thousands of years of domestication. The sequencing efforts were made possible because several of the scientists involved in today's studies recently sequenced the two "parent" species of most commercial cotton varieties—an Old World cultivated cotton and a New World wild cotton.

The results will allow scientists to analyze two sets of extensive DNA data, compiled independently of each other, compare the results and exploit cotton's genetic diversity by tapping into the potential of genes found in the 10,000 accessions of exotic and wild cotton plants in the ARS Cotton Germplasm Collection in College Station, Texas.

The papers, with a list of the contributing authors, can be found at:

http://www.nature.com/nbt/journal/vaop/ncurrent/full/nbt.3207.html

http://www.nature.com/nbt/journal/vaop/ncurrent/full/nbt.3208.html

ARS is USDA's principal intramural scientific research agency, and this research supports the USDA priority of promoting American agriculture by conducting cutting-edge research and expanding markets at home and abroad.

Categories: USDA

New Procedure to Test NDV Vaccines

USDA Agricultural Research Service - Wed, 04/15/2015 - 10:32
New Procedure to Test NDV Vaccines / April 15, 2015 / News from the USDA Agricultural Research Service
Read the magazine story to find out more.

 Chickens. Link to photo information
ARS scientists have improved methods for evaluating vaccines against Newcastle disease virus, which could lead to better protection from this virulent poultry disease. Click the image for more information about it.


For further reading

New Procedure to Test NDV Vaccines

By Sandra Avant
April 15, 2015

U.S. Department of Agriculture (USDA) scientists have developed an improved Newcastle disease virus (NDV) vaccine evaluation procedure that could be used to select better vaccines to treat the disease.

Newcastle disease, one of the most important poultry diseases worldwide, can cause severe illness in chickens and other birds. Severe, or virulent, strains rarely occur in poultry species in the United States, but they are regularly found in poultry in many foreign countries.

Available commercial NDV vaccines perform well in chickens infected with virulent NDV under experimental conditions. They also perform well under field conditions where virulent virus is not common. However, they often fail in countries where virulent viruses are endemic.

At the Agricultural Research Service's (ARS) Southeast Poultry Research Laboratory (SEPRL) in Athens, Georgia, microbiologist Claudio Afonso and veterinary medical officer Patti Miller have updated the traditional vaccine evaluation method, which does not compare vaccines or take into account suboptimal field conditions.

Under perfect conditions, vaccines should work, but conditions are not always perfect in the field, according to Miller. Chickens sometimes get less than the required vaccine dose and don't always have the minimum amount of time required to develop an optimum immune response.

The improved vaccine-evaluation procedure compares vaccines made using genes from the same viral strain-or genotype-that the birds are exposed to in the field to vaccines made with a strain that differs from the virus birds are exposed to.

Using the improved procedure, scientists inoculated chickens with different vaccine doses before exposure to a high dose of virulent NDV. Birds given the genotype-matched vaccine had reduced viral shedding, superior immune responses, reduced clinical signs, and increased survival than the birds vaccinated with a different-genotype vaccine. By using genotype-matched vaccines, viral shedding and death were significantly reduced.

ARS is USDA's principal intramural scientific research agency, and this research supports the USDA priority of promoting international food security.

Read more about this work in the April 2015 issue of AgResearch magazine.

Categories: USDA
Syndicate content