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Calf Maintenance in Cold Weather

Low Temperatures and Negative Energy Balance in Calves

D.C. Sockett DVM, PhD, Wisconsin Veterinary Diagnostic Laboratory
T.J. Earleywine PhD, Director of Nutrition Land O’ Lakes Animal Milk Products

Cold weather has arrived in the upper Midwest. Calf raisers know that cold temperatures increase the calf’s maintenance requirements for energy, but many do not know that the maintenance requirements also increase for protein and fat-soluble vitamins if the calf is ill from conditions like scours and pneumonia. Optimizing nutrition of sick calves can make the difference between a dead and a healthy calf.

It is important for livestock producers and veterinarians to understand that when the ambient temperature drops to 15 °F, feeding 3 quarts of milk (12.5% total solids) or a 22% protein, 20% fat milk replacer powder (12.5% total solids) twice a day will provide an 88 lb. calf with enough nutrition for less than 0.75 lbs/day of growth.  However, if the calf is stressed further (draft, wet or dirty hair coat, develops scours, pneumonia etc.), there is insufficient energy and protein in the diet to meet the needs of the calf, and she will begin losing weight. Since calves are born with roughly 3-4% of body weight as fat, they will die if the negative energy balance continues for more than 3-5 days. Calf scours is a common problem on US dairy operations: therefore, winter feeding programs should be formulated to take into account the increased protein, fat-soluble vitamins and energy demands caused by calf scours. Also, calves should be provided with a jacket and kept in a dry, draft-free environment that is bedded with straw deep enough to cover their legs. Calves should be offered a highly palatable calf starter that is high in protein (18-22%) and energy beginning at 2-3 days of age and have access to free-choice (low sodium/not softened) warm water within 30 minutes of being fed milk or milk replacer.

Winter Feeding Program

Since ruminants do not metabolize fat as efficiently as non-ruminants, just providing more fat in the diet is the least satisfactory way of providing additional nutrition to the calf. The diet must be consistent (less than 1% daily variation in percent total solids) and have enough energy and protein so the calf can have efficient, lean growth, adequate immune function and healing of damaged tissue caused by events like scours or pneumonia. The dairy producer can pick one of the following 3 options:

  • Continue to feed the calves 3 quarts of milk or milk replacer twice a day but increase the total solids content from 12.5 to 15%. To avoid problems, producers need to work closely with their dairy calf nutritionist if they choose this option.
  • Continue feeding the calves twice a day but increase the volume of milk or milk replacer per feeding from 3 to 4 quarts.
  • Feed the calves 3 quarts of milk or milk replacer 3 times a day instead of twice a day. There should be at least a 13-14 hour interval between the first and third feeding. This is the best option because calves do better when they are fed three times a day instead of twice a day.

Update on MDR Salmonella serotype Heidelberg

Update on MDR Salmonella serotype Heidelberg Case Count

The WVDL and our state and federal collaborators would like to remind veterinarians and producers to use caution when working with animals with confirmed or suspected multidrug resistant (MDR) Salmonella enterica subspecies enterica serotype Heidelberg. To date, there are 54 confirmed human infections in 15 states (n=18 in Wisconsin; Figure 1), in which 35% (n=17) of infected people have been hospitalized and 15% (n=8) had invasive disease.  Moreover, 33% (n=18) of ill persons were under the age of 5 years.  There continues to be human infections with MDR Salmonella ser. Heidelberg (Figure 2) where 63% (n=34) reported having contact with cattle including ill dairy beef calves. The Center for Disease Control and Prevention (CDC) has updated their website ( and provide several documents related to advice and information for livestock handlers, veterinarians and healthcare providers.

Figure 1: People Infected with the Outbreak Strains of Salmonella Heidelberg, by State of Residence, as of October 30, 2017 (n=54)


Figure 2: People Infected with the Outbreak Strains of salmonella Heidelberg, by Date of Illness Onset


The WVDL continues to isolate MDR Salmonella ser. Heidelberg from bovine tissues and feces.  We would like to stress the importance of cleaning and disinfection when this MDR Salmonella has been identified on a premise.  Preliminary evidence suggests that even after 1-2 years post identification of a MDR Salmonella ser. Heidelberg on a premise, we are able to culture Salmonella ser. Heidelberg from one or more locations on that premise.  Below are the number of MDR Salmonella ser. Heidelberg cases that the WVDL has identified from 2009 to 2017 (U.S. and Wisconsin maps). As expected Wisconsin has the most number of isolates at 61 with Missouri at 33 (Figure 3).  Additionally, Barron County (n=10) has the most isolates followed by Marinette and Shawano Counties (n=6 each) and Grant County (n=5) (Figure 4). The data here is a gross under estimation of the true burden of disease. The WVDL provides information about cleaning and disinfection protocols, bovine environmental sampling instructions, Salmonella molecular and culture testing options and work flow and a Salmonella ser. Heidelberg interview questionnaire on our website in the Diagnostic Aids tab.


Figure 3: Map of Salmonella ser. Heidelberg isolates by State from 2009-2017.


Figure 4: Map of Salmonella ser. Heidelberg isolates by Wisconsin County from 2009-2017


The WVDL continues to work closely with state and federal agents to make producers, veterinarians, physicians and other interested parties aware of this MDR zoonotic disease.  WVDL staff have recently given presentations at:

1) The American Association of Veterinary Laboratory Diagnosticians (AAVLD) Annual Conference on October 15 in San Diego, Calif. (Megin Nickels of the CDC also talked on this topic.)

2) The Inform 2017 Conference on November 8 in Garden Grove, Calif.  Additionally, a USDA veterinarian talked about preliminary data from a case control study the WVDL is participating in.

3) The One Health Symposium on November 10 in Madison, Wis.

4) The Conference of Research Workers in Animal Diseases (CRWAD) in Chicago, Ill. on December 5.



CDC Re-Opens Salmonella Outbreak Investigation

New human cases of Salmonellosis caused by Multi-drug Resistant (MDR) Salmonella Heidelberg spark re-opening of outbreak investigation


A multi-state outbreak investigation that began in July 2016 after a 16-year-old boy became ill after buying calves for a 4-H project has been re-opened by the Centers for Disease Control and Prevention (CDC). As of August 2, 2017 there have been 46 confirmed human cases of MDR Salmonella enterica subspecies enterica serotype Heidelberg reported to the CDC and other local health officials, with ten of these cases reported since April 2017. The outbreak now spans across 14 states and has hospitalized 14 (30%) people. Two-thirds of people reported having contact with dairy bull calves or other cattle just prior to onset of symptoms. More than half of the illness in Wisconsin occurred in children under 10 years of age.

Whole genome sequencing confirmed that 33 human, 65 cattle and 11 environmental samples have multiple antimicrobial resistance genes leading to no available antimicrobial for treatment of bovine illness and few treatment options for human illness.  Whole genome sequencing of human, bovine and environmental isolates also confirmed that these strains are highly related.  There are two main variants of this Salmonella ser. Heidelberg in the cattle population and one them is highly pathogenic.  Most cases identified are from the highly pathogenic strain and in Wisconsin only the highly pathogenic strain has been identified.

Although no new human cases have been identified in Wisconsin since December 2016, the WVDL has isolated more than twice the amount of MDR Salmonella ser. Heidelberg than this time last year indicating the outbreak has not slowed in the cattle population. The WVDL continues to work closely with other state and federal officials to monitor and prevent the transmission of MDR Salmonella ser. Heidelberg from cattle to humans.

More information on this on-going investigation and to stay up-to-date on recent happenings, see the links below for several federal, state and local websites.


Center for Disease Control and Prevention (CDC)

Wisconsin Department of Health Services

Wisconsin Department of Agriculture, Trade and Consumer Protection

Wisconsin Veterinary Diagnostic Laboratory




Eastern Equine Encephalitis Strikes in West Central Wisconsin

Eastern equine encephalitis strikes in West Central Wisconsin

The following alert was issued today by Wisconsin’s Department of Agriculture, Trade and Consumer Protection (DATCP).

Two Quarterhorse yearling fillies from Monroe County are the first to become infected with Eastern Equine Encephalitis (EEE) this year. One horse died and the other was euthanized.

Because EEE normally emerges in mid- to late summer and remains a threat until the first killing frost, veterinarians are encouraged to discuss vaccination and mosquito abatement with their horse owning clients.

Horses that have not already been vaccinated this year for EEE or other mosquito-borne diseases are at greater risk, but it is not too late to vaccinate.

Horses that have never been vaccinated will need two doses, two to four weeks apart, and the vaccine will take at least two weeks to build up enough antibodies to protect them. Vaccines will not protect horses that have already been infected when they receive the injections. Vaccines are available that protect against other strains of equine encephalitis along with EEE, and a separate West Nile virus vaccine is also available.

Last year, Wisconsin had 19 confirmed cases of EEE and seven cases of WNV, but there could have been many more unconfirmed cases.  Both EEE and WNV are reportable diseases, so veterinarians should notify the Division of Animal Health when a case is suspected.  EEE should be reported within one day and WNV within ten days following the reporting requirements outlined on our website:

Animal Disease Reporting Requirements

Wisconsin Poultry Producers and Interstate Movement to Iowa

LPAI Testing for Wisconsin Poultry Producers and Interstate Movement to Iowa

Purpose: The State of Iowa requires serology and PCR testing for avian influenza prior to interstate movement from Wisconsin. WVDL is setting up special testing for Wisconsin poultry producers to facilitate this movement.

Iowa is currently requiring permits for poultry and poultry products from Wisconsin to Iowa and if there are any questions, they should contact Iowa.

Here is a link to their web site:


Test logistics at WVDL:

  1. Serology for antibody: WVDL has the NPIP-approved test for antibody (AGID). This test is performed at the Barron Laboratory ONLY, is a 24-hour test and is set up at 2pm Mon-Thurs.
  2. PCR for virus nucleic acid: WVDL has the NPIP-approved test for AI PCR. This test is performed at the Madison Laboratory ONLY and will be set up on Mon-Fri, once per day, as special runs during the required testing period.

a. Samples must be dropped off in Madison by 10am for same day results for movement of animals the following day (8AM) to fit the requirement of 24 hours from sampling of animals to shipment. Depending on location in Wisconsin, overnight UPS shipping may be allowed for PCR testing. This will increase time to maximum of 36 hours from sampling of birds to shipment and PRODUCERS MUST contact the Iowa State Veterinarian’s office for prior approval.  Dr. David Schmitt (515) 281-8601.

b. Each PCR test (up to 11 swabs per test) will have an expedited testing fee added.

c. Please call ahead for testing so we can be prepared to accommodate your testing needs to the best of our ability.

d. Any NPIP-approved laboratory can be used for PCR testing.  The Minnesota Veterinary Diagnostic lab is the next available option. Minnesota runs  PCR Mon-Fri and samples must arrive by 8am.

Testing supplies:

1. Testing supplies can be ordered at Under the drop-down menu from “Submission Guidelines,” click on “Forms” and “Avian Swab Kit for PCR Order Form.”

b.  Directly under the link to this form is a video that demonstrates swabbing birds.

i. NOTE: Testing has been updated since the production of this video and NPIP now allows up to 11 swabs per tube.

2. Shipping labels can be ordered and emailed for $7 overnight ground UPS. See our website for details:

3. Testing and shipping supply orders can be taken over the phone, by fax, or by emailing completed forms to See our website for phone and fax numbers.

UW Identifies Flu Strain Affecting NYC Shelter Cats as H7N2 Influenza

CONTACT: Sandra Newbury, 608-335-2122,

UW Identifies Flu Strain Affecting NYC Shelter Cats as H7N2 Influenza

MADISON – The Wisconsin Veterinary Diagnostic Laboratory at the University of Wisconsin-Madison has identified the influenza A strain involved in an outbreak among cats in a New York City animal shelter as low pathogenic avian influenza H7N2, a rare subtype that has not been found previously in domestic felines.

The Shelter Medicine Program at the UW-Madison School of Veterinary Medicine is working closely with New York City’s Manhattan Animal Care Center (ACC-Manhattan) and the New York City Health Department to manage the situation, which includes establishing a quarantine facility while the Manhattan center is disinfected.

Cats that have contracted the H7N2 strain in the shelter have displayed upper respiratory symptoms such as runny nose, congestion, persistent cough and lip smacking, but the illness has not been severe. One cat was euthanized after developing pneumonia. No other species of animals from the shelter, including dogs, have tested positive for the virus.

“While we are concerned about this new infection, the cats are experiencing only mild to moderate illness, but a few have developed pneumonia,” says Sandra Newbury, clinical assistant professor at the veterinary school and director of the UW Shelter Medicine Program. “Many of the cats who were initially ill are already recovering. We do want people to be aware of what is happening, but influenza infection is unlikely in cats that have not had contact with cats from New York City’s Manhattan Animal Care Center.”

The first cases of influenza at the shelter were reported in late November when a private company, IDEXX Reference Laboratories, tested sick cats housed at ACC-Manhattan. The shelter then approached the UW Shelter Medicine Program and WVDL for more assistance since both helped manage outbreaks of a different strain of influenza that affected dogs and cats in the Midwest earlier this year and in 2015.

Further testing at WVDL found additional positive samples and led to identification of the H7N2 strain, a finding that has been verified by the U.S. Department of Agriculture’s National Veterinary Services Laboratories. The California Animal Health and Food Safety Laboratory at the University of California, Davis also confirmed the presence of H7N2 influenza virus after IDEXX provided samples to that lab for testing.

“This is the first time H7N2 has been detected and transmitted among domestic cats,” says Kathy Toohey-Kurth, clinical professor and head of the WVDL’s virology section.

Several cases of H7N2 were found in commercial poultry in the United States between 2000 and 2006, and it may be able to spread to other animals. There have been only two cases of H7N2 found in humans, and both cases ended with full recovery. The virus is thought to pose low risk to people. No human infections related to this case have been identified to date.

While influenza infection is unlikely in cats that have not had contact with infected felines from the shelter, owners whose animals show signs of influenza should contact their veterinarian for instructions. Cats suspected to be infected with the virus should be housed separately from other animals and precautions should be taken to prevent spread of the virus on hands and clothing.

“We’ll continue to work with the shelter to help manage the case and offer testing to any cats in rescue groups that are affected,” says Newbury. “We are hoping that offering this kind of diagnostic support will help rescue groups identify if they have cats with the virus so they can isolate them in order to stop the spread.”

Diagnostic testing conducted by the WVDL for animals that have come from the New York City shelter since Nov. 12 will be paid for by a generous gift from Maddie’s Fund, a family foundation that seeks to “revolutionize the status and well-being of companion animals.”

Shelters and rescue groups may contact the UW Shelter Medicine Program at with testing inquiries or questions regarding influenza in cats and dogs, and can look for updates at More details about the program’s partnership to provide diagnostic testing for shelters can be found on its diagnostic testing webpage.

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-Nik Hawkins,, 608-263-6914

Increased Awareness for Multi-drug Resistant Salmonella Heidelberg Infections

Notice of Increased Awareness for Multi-drug Resistant Salmonella enterica subspecies enterica serotype Heidelberg

High zoonotic potential for farm workers, especially children

Recently, the Wisconsin Veterinary Diagnostic Laboratory (WVDL), the Wisconsin Division of Public Health (DPH), the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP), the Wisconsin State Laboratory of Hygiene (WSLH) and the Centers for Disease Control and Prevention (CDC) have been tracking a multi-drug resistant (MDR) strain of Salmonella enterica subspecies enterica serotype Heidelberg (Group B).  The reason for this close collaboration is the strong connection between human infections and recent bull calf purchases.  The purpose of this communication is to educate the veterinary community of the risk these MDR Salmonella Heidelberg pose to both cattle and people, provide testing options for diagnosis, and disinfection recommendations.

Currently, there are twelve confirmed human infections from seven Wisconsin counties in 2016. The median age for Wisconsin residents with Salmonella Heidelberg infections is 7 years old, and four individuals were hospitalized.  Upon interview, greater than 90% of the infected individuals reported purchasing Holstein bull calves from livestock dealers or sales barns. Many of these calves died shortly after becoming ill.  During 2015 and 2016, the WVDL has isolated several MDR Salmonella Heidelberg isolates from calves located in mostly Wisconsin, but isolation has also occurred from calves located outside of Wisconsin during 2015 and 2016.  Pulsed-field gel electrophoresis (PFGE) and whole genome sequencing of 2016 isolates indicates that the human and bovine Salmonella Heidelberg isolates are very closely related, and may share a common source.  This strain of Salmonella Heidelberg is highly pathogenic and multi-drug resistant; only one antimicrobial drug is an effective treatment option for human cases and no effective options exist for cattle.  Individuals working with sick pre-weaned calves, particularly bull calves that have been recently purchased, are recommended to adhere to strict biosafety protocols and wash hands, change clothing, and clean affected areas and items frequently.  Children and immunocompromised individuals should limit their access to calves with diarrhea.  Additionally, any human diarrheal illnesses should be seen by a physician and reported to DPH if salmonellosis is confirmed.

Veterinarians suspecting salmonellosis, particularly infection caused by Salmonella Heidelberg, should submit fecal samples for Salmonella culture and/or PCR to the WVDL.  Results for confirmation of Salmonella are within 24-72 hours with serotyping taking an additional 24-72 hours.  Fecal samples should be collected in a leak-proof vial rather than glove, Whirl pack, or bag as these are more likely to leak.  Culture-positive Salmonella isolates will be serotyped and Salmonella Heidelberg isolates will be subject to antimicrobial susceptibility testing to confirm MDR status. WVDL staff veterinarians will contact submitting veterinarians upon isolation of this MDR Salmonella Heidelberg to discuss herd health, provide cleaning and disinfection recommendations and supply the veterinarians with an interview questionnaire to be filled out.

Cleaning and disinfection is absolutely necessary after confirmation of Salmonella as the cause of calf diarrhea or adult enteric disease.  This is particularly important for this particular MDR Salmonella strain, given the human and bovine health implications and lack of antimicrobials available.  Reinfection on the affected premise is highly likely and has been detected with this outbreak; therefore, it is highly recommended to perform environmental testing for Salmonella.  The WVDL has kits specific to this type of testing and cleaning and disinfection protocols that producers can use.

The WVDL, DATCP and DPH would like to increase surveillance for MDR Salmonella Heidelberg and encourages veterinarians to submit diagnostic samples when possible.  Veterinarians, please encourage producers to submit samples from suspect animals, particularly pre-weaned dairy calves that were recently purchased and die suddenly and unexpectedly.  Other state veterinary diagnostic laboratories have been notified of this outbreak and are prepared to culture diagnostic samples for Salmonella.  Salmonella Group B or Heidelberg isolates will be submitted to NVSL for PFGE and whole genome sequencing.  Cooperation between Wisconsin veterinarians, producers, and the human and animal health officials should reduce the incidence rates of salmonellosis in both humans and animals.

For more information please contact the following authorities:

Wisconsin Veterinary Diagnostic Laboratory at 608-262-5432 and or The WVDL will respond to requests within 24-48 hours during the work week.

Wisconsin Division of Public Health at 608-267-7143 and

Department of Agriculture, Trade, and Consumer Protection at 608-224-5012


Optimize Your Diagnostic Testing Using The Best Transport Media

PCR testingOptimize your diagnostic testing with the best media for sample transport


Transport MediaTo maximize the diagnostic potential of your diagnostic samples, the WVDL recommends using M6 viral transport media (red arrow) or sterile saline for any PCR testing.  Samples should be sent on ice overnight to WVDL using our low-cost UPS shipping. Aimes charcoal (yellow arrow) and Porta-cul agar gel media are best used for culture and antimicrobial sensitivity testing but in general, bacterial culture transport systems have inhibitory substances that may interfere with PCR testing.  Aimes and all other bacterial culture medias will NO LONGER be accepted for PCR tests.

It is also important to remember that wood and cotton swabs are not appropriate for PCR because they are manufactured with bleach, which damages nucleic acid.  Use polyester or Dacron with plastic sticks.  Please see our website to order media and collection supplies.

Wisconsin Canine Influenza Cases by County for 2016

Wisconsin CIV PCR Positive Cases by County

The PDFs below indicate which counties in Wisconsin had confirmed Canine Influenza Virus (CIV) cases in each of the first three months of 2016.  To date, only three counties in Wisconsin have reported CIV cases.




Canine Influenza Virus Found in Cats


 The following article is a re-print of one posted earlier this week on the University of Wisconsin School of Veterinary Medicine (SVM) website.  The SVM’s Dr. Sandra Newbury and WVDL’s Dr. Kathy Toohey-Kurth have recently found a group of cats from an Indiana animal shelter to be infected with the canine influenza virus (CIV).   The complete article follows.


UW Shelter Medicine, WVDL find canine influenza transmitted to cats in Midwestern shelter

CONTACT: Sandra Newbury, 608-335-2122,

MADISON – It may be called canine influenza, but Sandra Newbury, clinical assistant professor and director of the Shelter Medicine Program at the University of Wisconsin School of Veterinary Medicine has confirmed that the virus that sickened a large number of dogs in the Midwest last year has now infected a group of cats in the region.

Newbury, in collaboration with Kathy Toohey-Kurth, virology section head at the Wisconsin Veterinary Diagnostic Laboratory, recently tested multiple cats at an animal shelter in Northwest Indiana and found them positive for the H3N2 canine influenza virus.

“Suspicions of an outbreak in the cats were initially raised when a group of them displayed unusual signs of respiratory disease,” Newbury says. “While this first confirmed report of multiple cats testing positive for canine influenza in the U.S. shows the virus can affect cats, we hope that infections and illness in felines will continue to be quite rare.”

Feline cases previously reported in South Korea suggested that the virus – which was not seen in the U.S. until 2015 – was capable of making the leap from dogs to cats. However, just one cat tested positive for H3N2 on a single occasion in the U.S. last year. In that case, no repeated sampling was done because the sample was not known to be positive until long after the cat’s symptoms had resolved.

It now appears the virus can replicate and spread from cat to cat.

“Sequential sampling of these individual cats have shown repeated positives and an increase in viral loads over time,” Toohey-Kurth says, referring to the amount of virus found in any given sample.

Preliminary work to study the genetic signature of the virus shows it to be identical to the H3N2 virus that infects dogs. Researchers at WVDL are currently completing a full genetic analysis and study of the virus.

Newbury and the UW Shelter Medicine team are working closely with the animal shelter to manage the influenza outbreak. A number of dogs at the shelter have also tested positive for the virus.

“At this time, all of the infected cats have been quarantined, and no infected cats or dogs have left this shelter,” Newbury says.  “We will continue to watch carefully for instances of the disease.”

Cats that have contracted the virus in the shelter have displayed upper respiratory symptoms such as runny nose, congestion and general malaise, as well as lip smacking and excessive salivation. Symptoms have resolved quickly, and so far, the virus has not been fatal in cats.

Infected dogs may develop a persistent cough, runny nose and fever. Some dogs will show no symptoms, while others exhibit more severe signs of illness. The virus has been linked to some deaths in dogs, but most dogs recover with supportive care.

Dogs and cats infected with canine influenza virus should be housed separately from other animals and precautions should be taken to prevent spread of the virus on hands and clothing.

An H3N2 vaccine is now available for dogs, but no vaccine is currently approved or recommended for cats. A veterinarian can recommend whether or not to seek an H3N2 canine influenza vaccine for dogs.

Visit the WVDL website for more information about sampling and testing for canine influenza.  Shelters can also contact the UW Shelter Medicine Program with testing inquiries or questions regarding canine influenza. More details about the program’s partnership to provide diagnostic testing for shelters can be found here.

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— Ashley Voss,, 608-262-3425

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