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Antibiotic drug use in food animals focus of October workshop

Cows feed at a California dairy. (Photo: Wikimedia Commons)
New guidelines being implemented by the U.S. Food and Drug Administration – effective Jan. 1, 2017 - require label changes allowing only therapeutic uses of some medically important antimicrobial drugs, and call for increased veterinarian oversight for these drugs used in animal feed. The drugs are currently sold over the counter with unrestricted access. According to the Centers for Disease Control and Prevention, overuse may be related to the development of antibiotic-resistance-related infections, which kill 23,000 people and sicken millions each year.

The UC Davis School of Veterinary Medicine and the Farm Foundation recently brought together the state's livestock and poultry producers, their feed suppliers, veterinarians and UC Agriculture and Natural Resources Cooperative Extension specialists to discuss a changing landscape of antibiotic drug use in food animals.

Regional industry leaders were among the speakers at the workshop, held at the UC Davis School of Veterinary Medicine. They included Chuck Ahlem of Hilmar Farms, Bill Mattos of the California Poultry Federation, Dr. Stuart Hall of Feedlot Health Management Services, and Dr. Marit Arana of A.L. Gilbert Company. Dr. Craig Lewis of the U.S. FDA and Dr. Kathe Bjork of the USDA were also present to provide an overview of the complex public health issue of antibiotic resistance, the new guidelines and available to answer questions from the nearly 70 participants.

A welcome by Sheldon Jones with the Farm Foundation, Dean Michael Lairmore with the UC Davis School of Veterinary Medicine and meeting facilitator Kevin Ochsner kicked off the morning. In his address, Lairmore emphasized the important role the school plays in reducing antibiotic resistance and working with its partners to build consumer trust in a safe food supply.

“Our school's role is critical in training the next generation of veterinarians on this issue and providing evidence-based science on the ethical, proper use of antimicrobials in food animals,” said Lairmore said.  “Our ability to bring people together around important topics like this and our research and public service programs place UC Davis veterinary scientists at the forefront of this issue."

Dean Lairmore, Chuck Ahlem with Hilmar Farms and VMTRC's Terry Lehenbauer

How to best move forward with the new guidelines was a central theme among featured speakers representing producers, veterinarians and the feed industry.

Chuck Ahlem with Hilmar Farms, the world's largest single site cheese and whey manufacturer that sells products in more than 40 countries, said he believes the changes will help strengthen the relationship between producers and veterinarians. Bill Mattos with the California Poultry Federation emphasized how important the issue is to the state's poultry industry, citing California as producing more chickens this year without antibiotics than any other state.

State Veterinarian Dr. Annette Jones provided an overview of CA Senate Bill 27
Lunch speaker California State Veterinarian Dr. Annette Jones provided an overview of CA Senate Bill 27 - passed by the legislature and currently before Gov. Jerry Brown – that would put into place the FDA guidelines and eliminate the unnecessary use of antibiotics in animals, such as those used to promote growth. If the bill becomes law, California will lead the nation in addressing the serious public health threat of antibiotic resistance.

Afternoon break-out sessions allowed participants to discuss the management challenges and impacts ahead due to the changes, and provided state and federal agency staff, veterinary medicine faculty and UC Agriculture and Natural Resources Cooperative Extension specialists insight into the changes needed to meet the requirements.

The Davis workshop was one of 12 that the Farm Foundation is hosting across the country. A report based on comments gathered at the workshop will be presented at a national summit to be convened by the Farm Foundation later in 2015 to advance the conversation on the industry's adaptation to the changing landscape of antibiotic drug use.

Examples of the UC Davis School of Veterinary Medicine's programs to help prevent unwanted drugs from entering the food supply include the resources of the federally funded Food Animal Residue Avoidance Databank, research and vaccine development through the Center for Food Animal Health, surveillance and diagnostic testing at the California Animal Health and Food Safety Laboratory System and international outreach conducted by the Western Institute for Food Safety and Security. (Read more about these programs and the critical role veterinarians play in food safety and public health in Dean Lairmore's recent op-ed in the Sacramento Bee.)

Author: Monique Garcia Gunther

Posted on Thursday, October 8, 2015 at 1:28 PM

Low residual dry matter on rangeland a concern heading into wet season

Leaving sufficient dry matter on rangeland prevents soil erosion and creates a conducive environment for diverse plant communities to thrive.
Over the past few years, drought has negatively affected everyone in the state and ranchers are no exception. Due to the drought, most areas have seen a decline in forage production and water availability, and as a result many livestock producers reduced their herd sizes and grazing season.

With some recent forecasts bringing encouraging news about a potential El Niño, some ranchers have been asking about what they should expect in terms of forage production, if and when the rains come. What they want to know is how soon rangeland productivity will reach the pre-drought levels again. One issue that I always draw their attention to is the levels of residual dry matter (RDM) on the rangelands. Even with the reduction in herd sizes and shorter grazing seasons employed by most producers, more rangelands now have less than recommended RDM levels.

RDM is a measure of the old plant material (without counting summer annuals) that are left standing or on the ground before the fall precipitation comes. It is a great indicator of both forage production and grazing intensity. These leftover plant materials are critical on California rangelands to reduce erosion and nutrient loss, and to create a conducive environment for diverse plant communities to thrive. Optimum RDM levels are site specific, they range from 100-2,100 pounds per acre, and depend on precipitation zone, slope and tree canopy cover. Ideal RDM levels increases with precipitation and slope, and decreases with tree cover. Studies show that too low or too high RDM levels will reduce species composition and forage production, both factors critical to any livestock production system. The good news is that annual rangelands are resilient and will likely return to normal production within two years after bringing RDM level to recommended standards.

Knowing the RDM standards for one's rangeland and continuously monitoring is an important step towards achieving sustainable rangeland management and livestock production.

Details about RDM standards, data collection methods and more can be found in the free UC Agriculture and Natural Resources publication Guidelines for Residual Dry Matter on Coastal and Foothill Rangelands in California

Author: Fadzayi Mashiri, Ph.D.

Posted on Friday, October 2, 2015 at 10:24 AM

Use compost for water conservation

Organic matter from the garden can be turned into compost and added to landscape soil to increase water holding capacity.
Some of the best practices for maintaining healthy home gardens and landscapes also cut water use, a particularly important benefit during the drought. That's the case with compost. UC Agriculture and Natural Resources' environmental horticulture advisors and UC Master Gardeners have long encouraged Californians to liberally use compost to improve their soil.

“Adding compost to your soil on a regular basis increases the amount of water your soil can hold, therefore decreasing the amount of times you need to apply water to your landscape,” says Missy Gable, the director of the UC Master Gardener program, in the final installment of a six-part video series on water conservation in the home landscape.

Compost is organic matter – grass clippings, fallen leaves, spent bedding plants, vegetable peels, coffee grounds, etc. – that has been dampened and turned regularly so it is broken down by worms and micro-organisms. The finished compost, a dark black blend with a pleasant earthy smell, can be mixed into the native soil in the landscape.

Compost improves the soil texture, holds moisture, provides food for beneficial bacteria, and nutrients for plants.

View the video below:

Detailed information about the benefits of compost and instructions for home composting can be found in Composting is Good for Your Garden and the Environment, a UC ANR publication available for free download from the UC ANR publications catalog.

Additional videos in the UC ANR series on saving water in the landscape.

Prioritize your plants

Early-morning watering is best

Remove weeds from your landscape

Mulch the soil surface

Skip landscape fertilization

The videos are also available on the UC ANR YouTube channel.

An initiative to improve California water quality, quantity and security is part of the UC Division of Agriculture and Natural Resources Strategic Vision 2025.

Posted on Monday, September 28, 2015 at 10:49 AM

Sudden oak death moving to urban areas; 3 steps to protect oaks

Doug Schmidt, standing, and Matteo Garbelotto examine a bay laurel on the UC Berkeley campus.
Drought is decreasing but not defeating the pathogen that causes sudden oak death, according to a citizen science-assisted survey conducted this spring by a UC Agriculture and Natural Resources forest pathologist.

Results of the 2015 Sudden Oak Death Blitz survey reveal coastal mountain infestations in areas such as Big Sur (19% infection), the Santa Cruz Mountains (13% infection), and western Sonoma County (12% infection) remain high despite an overall decline in infection rates from 4.4% to 3.7% across California's 15 infested counties.

Sudden oak death (SOD) symptoms have been seen in Alameda, Contra Costa, Humboldt, Lake, Marin, Mendocino, Monterey, Napa, San Francisco, San Mateo, Santa Clara, Santa Cruz, Solano, Sonoma and Trinity counties.

“Understanding the current disease distribution is key to preventing sudden oak death spread. Citizen scientists have been an invaluable help with this task over the last decade,” said Matteo Garbelotto, UC ANR Cooperative Extension specialist in the Department of Environmental Science, Policy and Management at UC Berkeley, who organizes the annual SOD Blitz.

Several new SOD outbreaks of note were identified during the blitzes. Two infected California bay laurel trees were confirmed near UC Berkeley's West Gate, a high-traffic, high-risk area with many heritage oaks. An infected California lilac shrub was found in the Presidio of San Francisco's (part of the Golden Gate National Recreation Area) southeastern quadrant. An infected California bay laurel tree was confirmed in Danville (eastern Contra Costa County) in an area where SOD had not previously been reported, and an urban park in Saratoga was found infested for the first time.

These bay laurel leaves show P. ramorum symptoms.
“In an effort to protect habitat restoration in the Presidio, we are working to strengthen Best Management Practices to prevent the spread of SOD based on the Garbelotto lab recommendations,” said Christa Conforti, integrated pest management specialist at Presidio Trust in San Francisco. “In partnership with UC, the National Park Service, and the Golden Gate National Parks Conservancy, we are developing a Phytophthora prevention, detection and control strategy, which includes active participation in SOD Blitzes.”

Nineteen citizen science-based SOD Blitzes (largest number of blitzes to date) were held this spring, two of which were new this year – one in Trinity County and one on Kashia Band of Pomo Indian land in Mendocino County. The 504 volunteers surveyed nearly 10,000 trees from San Luis Obispo County, north to Mendocino and Trinity counties. Each volunteer was trained to identify Phytophthora ramorum (the plant pathogen known to cause SOD) symptoms on California bay laurel and tanoak leaves. “Blitzers” had up to three days to collect and record locations of symptomatic samples, which were then sent to the Garbelotto lab for DNA analysis to determine the presence or absence of the pathogen.

The SODMap mobile app shows a map of sampled trees.
SOD management workshops

Garbelotto is sharing results from the spring blitzes as well as new recommendations for SOD management at workshops being held around the Bay Area. Workshops will be held in Sebastopol on Nov. 3, in Berkeley on Nov. 4, andin San Rafael on Nov. 13. For details, see “Community meetings” at

For landowners in infested areas concerned about protecting their oak trees, Garbelotto will reveal his updated three-step SOD management plan. He will show them how to:

  1. Use the SODMap mobile app to help assess risk of oak infection (see
  2. Determine if California bay laurel trees near high-value oaks should be considered for removal (using a new buffer zone new chart -
  3. Apply phosphonates to high-value oak and tanoak trees to boost immunity (updated dosages and application frequencies at

Infection on California bay laurel and tanoak leaves indicates arrival of P. ramorum to an area, but true oak (California black oak, coast live oak, canyon live oak and Shreve's oak) infection typically requires a couple of years with wet conditions after pathogen arrival. Therefore, preventatively treating oaks to help ward off infection is best done when early indicator species first show symptoms, prior to oak infection and optimal conditions for the pathogen – cool and moist.

These surveys are made possible thanks to funding from the USDA Forest Service and the PG&E Foundation as well as help from the California Native Plant Society.

For more information on the workshops, go to or contact Katie Harrell at (510) 847-5482 or For more information on sudden oak death and P. ramorum, visit the California Oak Mortality Task Force website at


Posted on Friday, September 25, 2015 at 11:38 AM

Children’s magazine focuses on rangeland animals

The September 2015 issue of Jr. Animal Scientist focuses on rangeland.
Rangeland is where deer and antelope play. It is also home for grazing livestock and many other animals. “Almost half of the land on Earth is rangeland and one-third of the United States is rangeland,” the latest issue of Jr. Animal Scientist tells its young readers. A UC Agriculture and Natural Resources (UC ANR) advisor is among the scientists who contributed to the rangeland issue of the children's magazine. 

Jr. Animal Scientist is published by the American Society of Animal Science for children aged 5 to 12 who are interested in animals. For the September 2015 issue, members of the Society for Range Management collaborated with ASAS to provide photos and facts about rangeland.

Theresa Becchetti, UC ANR Cooperative Extension livestock and natural resource advisor for Stanislaus and San Joaquin counties, and Lisa Page, from the University of Arizona, served as co-editors for the special issue.

“Our goal is to have kids and their parents and teachers learn the value of rangelands, beyond being used to produce beef and lamb; they also provide habitat for wildlife,” said Becchetti. “Rangelands can produce energy – solar, wind and oil – while providing clean water and air and a place for recreation. These resources are protected by ranching families, the stewards who make their homes on rangeland.” 

In the magazine, readers will find descriptions of the different kinds of rangeland, a map of rangelands and photos of some wildlife species that live on rangelands. It also includes a word scramble and rangeland-related jokes (“Why do cows wear bells? Because their horns don't work!”)

“As a member of the Society for Range Management, and working on developing curriculum on rangelands in California, I was excited to be involved in the effort,” Becchetti said. “The magazine has a national circulation with a mix of families and schools.”

A PDF of the Jr. Animal Scientist rangeland issue can be viewed at


Posted on Thursday, September 24, 2015 at 9:13 AM

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