OKLAHOMA STATE UNIVERSITY CENTER FOR VETERINARY HEALTH SCIENCES — OKLAHOMA ANIMAL DISEASE DIAGNOSTIC LABORATORY Spring 2019 • Volume 21

In this Issue Histophilus somni Infection in Cattle

Histophilus somni Infection...... 1 Antimicrobial Susceptibility Profile of Histophilus somni Isolates at OADDL...... 2 Strobilocercosis in a Pet Rat ...... 2 Recent Lead Toxicosis Cases...... 3 Transport Medium for Trich...... 3 Director’s Note...... 5 Getting to Know Us...... 5 Request for Feedback...... 5 Faculty

Director: Dr. Keith L. Bailey – Pathology Figure 1. Brain from a heifer with histophilosis. Note the yellow-gray, purulent exudate in the leptomeninges overlying the ventral brainstem and part of the thalamus.

Assistant Director/Quality Manager: Histophilosis is an important disease of Emily J. Cooper feedlot cattle and manifests clinically as respiratory, neurological and cardiac Microbiology/Molecular Diagnostics: diseases. Histophilus somni is one of the Dr. Akhilesh Ramachandran major pathogens of bovine respiratory disease (BRD) complex, usually caus- Parasitology: ing fibrinous pleuropneumonia. The Dr. Yoko Nagamori bacterium can also invade the circula- tion and cause vasculitis, thrombosis in Pathology: multiple organs and septicemia. Figure 2. Heart from a heifer with histophilosis. Dr. Anthony W. Confer The neurological form of histophi- Note the locally extensive, necrotizing Dr. Craig Miller in the papillary muscle of the left losis is known as infectious thrombotic Dr. Grant Rezabek ventricular wall (arrow). meningoencephalitis (TME). Cattle Dr. Jerry Ritchey with the neurological form may devel- (Figure 2) may be observed. Myocardial Dr. Tim Snider op purulent meningitis (Figure 1) and is often limited to the papillary reported clinical signs include ataxia, Serology: muscle of the left ventricle of the heart. paresis, blindness and seizures. Dr. Grant Rezabek Histophilosis should be considered Occasionally, animals infected with among clinical rule-outs in cattle with H. somni die prior to observation of any Graphic Design/Layout: respiratory and neurologic signs. clinical signs. At necropsy, myocardial – Dr. R. Chien Clarissa Walton infarction and necrotizing myocarditis Spring 2019 • Vol. 21 OADDL E-NEWS Page 2 Antimicrobial Susceptibility Profile of Histophilus somni Isolates at OADDL: 2018 – 2019 Histophilus somni is a significant Table 1. Antimicrobial Susceptibility Profile for Histophilus somni respiratory pathogen of cattle and a Isolates at OADDL (January 2018 — March 2019) component of bovine respiratory dis- ANTIBIOTIC SUSCEPTIBLE INTERMEDIATE RESISTANT ease (BRD) complex. In 2018 and thus far in 2019, thir- Ceftiofur 100 0 0 ty-five percent (35%) of the H. somni Danofloxacin 57 0 43 isolates at OADDL were resistant to at Enrofloxacin 57 43 0 least 3 or more different classes of anti- Florfenicol 86 7 7 microbial agents, qualifying the isolates Oxytetracycline 21 0 79 as multidrug resistant (Table 1). OADDL continues to monitor H. 93 0 7 somni and Mannheimia haemolytica Spectinomycin 36 0 64 isolates for multi-drug resistance pat- Tilmicosin 57 21 21 terns. Tulathromycin 57 14 29 – Dr. A. Ramachandran Number of H. somni isolates tested = 14

Strobilocercosis in a Pet Rat 34th Annual GOAT & HAIR FIELD DAY APRIL 27, 2019 LANGSTON UNIVERSITY

Figure 1. Liver with attached parasitic cyst Figure 2. Juvenile tapeworm (Taenia from a pet rat. taeniaeformis) removed from the liver cyst.

A 2-year-old, spayed female, pet rat of infected rodents. Rodents can serve presented to OADDL for necropsy as an intermediate host by ingestion of after being treated for severe respira- eggs. In a rodent, the larva migrates TOPIC: Holistic Approach tory distress associated with left atrial through the intestine and then GUEST SPEAKERS: Ms. Gianaclis thrombosis. forms a cyst associated with the liver. Caldwell & Dr. Ann Wells During necropsy, a cystic struc- Strobilocercosis is usually non-patho- Free registration begins at 8 a.m. and ture was attached to the edge of the genic and an incidental finding during the first speaker will begin at 9 a.m. left medial liver lobe (Figure 1). The necropsy examination. Lunch can be purchased for $10. cyst contained a single, 14-15 cm long, Click on the following link to juvenile Taenia taeniaeformis, called a watch a video of a live strobilocercus in strobilocercus (Figure 2). this case being removed from the cyst: T. taeniaeformis is a common tape- Strobilocercus in a pet rat. worm found in cats following ingestion – Drs. S. Salopek & Y. Nagamori Spring 2019 • Vol. 21 OADDL E-NEWS Page 3 Recent Lead Toxicosis Cases at OADDL Over the past 12 months, OADDL received samples from 30 animals for lead testing. The samples included whole blood (24), liver (6) and kidney (1); blood and liver was received from one animal. Lead toxicosis was diagnosed in 6/30 animals (20%). Of the 6 animals with lead toxicosis, 5 were cattle and 1 was a bald eagle. The reported ages of the affected cattle ranged from 5 months to 5 years old (Table 1). Clinical signs in the affected cattle included blindness, depression, stupor, grinding teeth, drooling, seizures, twitching, stumbling and thrashing Table 1. Lead Toxicosis in Cattle from April 2018 – March 2019 DATE OF SUBMISSION prior to death. In one case, 5 animals AGE REPORTED CLINICAL SIGNS were dead within a 100-yard area. In TO OADDL another case, 3 cows died with central Blind, stuporous, grinds teeth 5 months May 2018 nervous system (CNS) signs and a and drools burned car battery was found on the Calf (unspecified August 2018 Seizures and CNS signs property. age) It has been suggested that some 8 months January 2019 Blind calves coming off winter pasture are Steer Blind, depressed and grinds February 2019 deficient to marginally deficient in (unspecified age) teeth trace minerals, and this imbalance CNS signs, twitching, leads them to preferentially seek out 5 years March 2019 stumbling, thrashing lead-containing (salty) substances prior to death such as exposed automobile battery plates, old plumbing, putty, drilling Calves with lead toxicosis may be logical animal is whole blood in EDTA. pipe thread compound, electrical cable found dead or exhibit neurologic signs. In dead cattle, fresh kidney and liver shielding, or paint on old outbuildings. The preferred sample to test in a neuro- are good samples to test.

Reminder: New Transport Medium for Trich PCR Testing of Bulls! SUMMER OADDL now offers an alternative to the Trich InPouch® for trichomoniasis SEMINAR PCR testing of bulls. Benefits of the new transport JUNE 21-22, 2019 medium include: • Inexpensive REGISTER TODAY • No incubation required (same-day testing) • Easier to handle • Longer expiration time Call us for details! (405) 744-6623 Online registration – Dr. K. Bailey open until June 11. Spring 2019 • Vol. 21 OADDL E-NEWS Page 4 Letter from the Director Your team at OADDL is off to a strong We extend our congratulations to OADDL is fully accredited by the start in 2019! all exhibitors at OYE, but particularly American Association of Veterinary Undoubtedly, many of you have our next generation of ranchers, farm- Laboratory Diagnosticians (AAVLD) probably heard about the recent diag- ers and livestock producers whose hard and is a proud member of the USDA’s nosis of porcine epidemic diarrhea work resulted in valuable scholarships. National Animal Health Laboratory virus (PEDv) at OADDL. And you In addition to testing for common Network (NAHLN). Our participation are probably aware that the outbreak diseases of swine like PEDv, OADDL in NAHLN allows us to test for foreign involved show pigs at the Oklahoma was recently approved to test for animal diseases and helps ensure that Youth Expo (OYE). African swine fever (ASF) virus. the state of Oklahoma can react quick- But what you may not be aware of Outbreaks of ASF are currently result- ly to any real or perceived livestock is how many Oklahomans are active- ing in high swine mortality in China, threats. ly engaged in OYE. The 2019 OYE Russia, southeast Asia, and parts of On behalf of concluded on March 22 and involved eastern Europe. This disease is a seri- OADDL, we are proud 21,159 head of cattle, pigs, goats and ous threat to U.S. swine and emphasizes to serve you and we sheep – making it the world’s largest the biosecurity measures we take every ask for your continued junior livestock show! day to protect our swine interests. support. – Dr. K. Bailey Getting to Know Us Alan Jones is originally from Monticello, Arkansas, and joined the Ideas/Suggestions for OADDL family as a lab technologist in November 2018. Before coming to Future Content OSU, he worked as an undergradu- We want to hear from you. Send us ate researcher helping to investigate your ideas and suggestions to larval over-wintering and springtime [email protected]. emergence of emerald ash borers in forest stands with green ash trees. Alan obtained his B.S. in wildlife management in 2017. In his spare Contact Us time, he enjoys playing his drums Oklahoma Animal Disease and guitars. He also enjoys being out- Diagnostic Laboratory doors, hunting, fishing, and looking Ph: 405-744-6623 for reptiles and macro-invertebrates Fax: 405-744-8612 in forested and wetland systems. www.cvhs.okstate.edu/oaddlFacebook “f” Logo CMYK / .eps Facebook “f” Logo CMYK / .eps Follow us on Facebook Christian Holcomb joined the Bacteriology lab in October of last year as a Senior Laboratory Technologist after graduating from Oklahoma State University with a B.S. in Microbiology. He is married to his wife Kaitlynn, and together they have one child, William. In his spare time he enjoys video games, reading, and cooking.

Oklahoma State University, in compliance with the Title VI and VII of the Civil Rights Act of 1964, Executive Order 11246 as amended, Title IX of the Education Amendments of 1972, Americans with Disabilities Act of 1990, and other federal laws and regulations, does not discriminate on the basis of race, color, national origin, sex, age, religion, disability or status as a veteran in any of its policies, practices or procedures. This includes but is not limited to admissions, employment, financial aid and educational services. Title IX of the Education Amendments and Oklahoma State University policy prohibit discrimination in the provision or services or benefits offered by the university based on gender. Any person (student, faculty or staff) who believes that discriminatory practices have been engaged in based on gender may discuss his or her concerns and file informal or formal complaints of possible violations of Title IX with OSU’s Title IX coordinator: the Director of Affirmative Action, 408 Whitehurst, Oklahoma State University, Stillwater, OK, 74078, (405) 744-5371 or (405) 744-5576 (fax). #5565