Mycoplasma ovis. What is it and why do we care? American Sheep Industry Convention San Antonio, TX February 1, 2018

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1 Mycoplasma ovis What is it and why do we care? American Sheep Industry Convention San Antonio, TX February 1, 2018 M. A. Highland, DVM, PhD, Dipl. ACVP Veterinary Medical Officer-Researcher USDA-ARS-Animal Disease Research Unit Pullman, WA

2 What is Mycoplasma ovis? Eperythrozoon ovis ( Epe ) prior to 2004 Hosts: domestic sheep and goats, deer, reindeer Infects the surface of RBCs (resembles basophilic stippling)

3 Mycoplasma ovis Worldwide distribution Australia*, NZ, Turkey, Norway, Japan Reports of infection/disease in U.S. rare Transmission Biting insects and ticks; needle reuse Transplacental transmission no data in literature

4 Clinical symptoms Jaundice +/- red urine (hemolysis), weight loss, illthrift (decreased weight gain, stunted growth), bottle jaw, neurological signs (anemia/hypoxia), diarrhea* Resemblance to: Mycoplasma ovis Enteric parasites (barber pole worm) Vitamin/mineral deficiency (copper, thiamine, E/selenium) Often subclinical...consequence of this? Meat and fiber production effects in the United States? Carcass condemnation (jaundice)?

5 Diagnosis Mycoplasma ovis Blood smear (easily mistaken for stippling) Complete blood count: ANEMIA Serum chemistry: +/- hypoglycemia Depends on how long blood sample sits and bacterial load PCR DNA isolated from whole blood, plasma, serum

6 Mycoplasma ovis (ongoing research - data analysis stage) ARS-Range Sheep Production Efficiency Research Unit U.S. Experiment Sheep Station Large number of accessible sheep for blood collection Ability to repeat sample and follow animals lifelong Production records and genetic information Repeat sampled ewes and lambs over 3 years (3x per year) Analyzing for impacts of infection on ewe and lamb production (Dr. Bret Taylor) Passive transfer does occur, although inefficient (~42% ewe prevalence, 5.1% pre-suckle lamb prevalence)

7 Mycoplasma ovis (Ongoing research - data analysis stage) NAHMS sera samples from 2001 and 2011 Distribution and prevalence in the U.S. Operation impacts on prevalence (NAHMS sample data analysis: Dr. Natalie Urie)

8 Thanks to.. ADRU-ARS-USDA and WSU - Don Knowles - Nic Durfee - Paige Grossman - Ralph Horn & James Allison - Stephen White & Michelle Mousel U.S.S.E.S. Dubois, ID USDA-APHIS (NAHMS) - Bret Taylor - Katherine Marshall - Animal Care Staff - Natalie Urie..

9 MYCOPLASMA OVIS IN U.S. SHEEP FLOCKS: SEROPREVALENCE AND ASSOCIATED RISK FACTORS N ATA L I E U R I E V E T E R I N A R Y E P I D E M I O L O G I S T M O N I TO R I N G A N D M O D E L I N G U S D A, A P H I S, V S J A N U A R Y

10 NAHMS National Studies Key Information Commodities are surveyed on a rotating basis Study objectives are set in partnership with industry and other stakeholders All studies depend on voluntary participation All studies utilize a statistically valid nationally representative sample 10

11 NAHMS National Studies Beef Cow-Calf Goats Catfish Beef feedlot Swine Layers Ranched Bison Equine Beef Cow-Calf Poultry Sheep Farmed Cervids Small-Scale Operations Dairy 11

12 NAHMS Serum Samples Tested Study Year # Sheep # Operations , , Total 19,673 1,182 12

13 Sheep-Level Mycoplasma ovis Seroprevalence Combined 2001 and 2011 Seroprevalence: 30.0% 40% 35% 35% 30% 30% 25% 25% 20% 20% 37.3% 32.2% 22.8% 22.5% 21.8% 20.2% 35.5% 33.8% 33.2% 29.2% 27.7% 29.3% 38.6% 32.0% 32% 31.0% 31.1% 32% 30.4% 26.5% 26.6% 27% 27% 25.2% 15% 15% 10% 10% 5% 5% 0% 0% West sheep Centralsheep 500+ East sheep Overall Overall Herded/ open range Fenced range Farm flock Overall

14 Operation-Level Seroprevalence Operations that had at least 1 M. ovis positive sample 2001: 77.7% 2011: 88.2% Overall: 82.7% Mean within-flock seroprevalence 2001: 34.6% 2011: 34.7% Overall: 34.6% 14

15 Preliminary Risk Factors Associated with M. ovis Detection Flock size Region Year of blood collection Requirement of preventive health practices Public land grazing Vaccinations 15

16 Percent of Operations with M. ovis present M. ovis Detection by Operation Requirements for New Additions P = Operations with NO preventive health practices for new additions were 2.1 times more likely to have M. ovis Any vaccinations Deworming External parasite treatment Ovine progressive pneumonia testing Johne s testing Scrapie susceptibility testing 82.1% 89.9% 80.0% Yes No No New Additions Required Preventive Health Practices 16

Percent of Operations with M. ovis present M. ovis Dectection by Grazing on Public Land P = 0.0230 98.5% 85.

17 Percent of Operations with M. ovis present M. ovis Dectection by Grazing on Public Land P = % 85.2% Operations that placed sheep to graze on public land were 3.5 times more likely to have M. ovis Yes Sheep grazed on public land No 17

M. ovis Detection by Vaccination Practices P = 0.0243 No vaccinations 74.5% Operations that administered vaccines were 1.

18 M. ovis Detection by Vaccination Practices P = No vaccinations 74.5% Operations that administered vaccines were 1.7 times more likely to have M. ovis Any vaccinations 84.0% **This does not mean that vaccines spread or cause M. ovis.** Percent of Operations with M. ovis present 18

19 Preliminary Risk Factors Associated with M. ovis Within-Flock Seroprevalence Flock size Region Year of blood collection Any ewes that aborted during the study years Disinfection of sheering equipment between sheep 19

20 Mean Within-Flock M. ovis Seroprevalence M. ovis Within-Flock Seroprevalence by Abortion Presence P = % 26.3% Operations WITH abortions had a 1.12 times higher within-flock M. ovis seroprevalence No abortion Any abortion during the study year 20

Mean Mean Operation Within-Flock level M. M. ovis ovis Seroprevalence Prevalence M. ovis Within-Flock Seroprevalence by Sheering Disinfection Practices P = 0.0375 30.6% 32.7% 28.

21 Mean Mean Operation Within-Flock level M. M. ovis ovis Seroprevalence Prevalence M. ovis Within-Flock Seroprevalence by Sheering Disinfection Practices P = % 32.7% 28.4% Operations that ALWAYS disinfected shearing 26.3% equipment had a 1.7 times higher M. ovis seroprevalence Always disinfected sheering equipment Sometimes or never disinfected sheering equipment **This does not mean that disinfecting shearing equipment No abortion spreads or causes M. ovis** Any abortion during the study year 21

22 Thank you to: Acknowledgements US Sheep Producers USDA Agricultural Research Service American Sheep Industry Association 22

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