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Journal of Wildlife Diseases, 44(4), 2008, pp. 1051–1055 # Wildlife Disease Association 2008

Preliminary Studies on the Etiology of Keratoconjunctivitis in (Rangifer tarandus tarandus) Calves in Alaska

Alina L. Evans,1,5 Russell F. Bey,1 James V. Schoster,2 James E. Gaarder,3 and Gregory L. Finstad4 1 Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, 1971 Commonwealth Ave., St. Paul, Minnesota 55108, USA; 2 Eye Consultants of Minnesota, Roseville, Minnesota 55113, USA; 3 Veterinary Eye Specialists, 1921 W Diamond Blvd., Suite 108, Anchorage, Alaska, 99515, USA; 4 Reindeer Research Program, University of Alaska, PO Box 757200, Fairbanks, Alaska, 99775; 5 Corresponding author (email: [email protected])

ABSTRACT: Keratoconjunctivitis outbreaks oc- and possibly contagious eye disease that cur each summer in reindeer (Rangifer tar- can leave blind or with impaired andus tarandus) herds in western Alaska, USA. vision. Keratoconjunctivitis is seen annu- This condition has not been well characterized nor has a definitive primary etiologic agent ally during the summer reindeer handlings been identified. We evaluated the eyes of 660 on the Seward Peninsula (Reindeer Re- calves near Nome, Alaska, between 29 June and search Program, University of Alaska 14 July 2005. Clinical signs of keratoconjuncti- Fairbanks, unpubl. data). vitis were observed in 26/660 calves (3.9%). Infectious keratoconjunctivitis has been Samples were collected from the conjunctival studied in numerous other . In sac of both affected (n522) and unaffected (n524) animals for bacterial culture, enzyme- , the primary pathogen has been linked immunosorbent assay testing for Chla- identified to be the piliated form of mydophila psittaci, and for polymerase chain Moraxella bovis (Ruehl et al., 1988). reaction assays for Mycoplasma and Moraxella Moraxella has been implicated in spp. No primary bacterial or viral etiologic infectious keratoconjunctivitis in agent(s) were isolated or identified. The cause of keratoconjunctivitis among reindeer calves (Alces alces), mule (Odcoileus hemi- was not determined, but it could involve an onus), and ( hircus; Dubay et anaerobic bacteria, a difficult-to-isolate viral al., 2000). Chlamydophila psittaci has also agent, stress associated with repeated handling, been isolated from infected eyes in mule ocular foreign bodies, exposure to corral dust or deer (Taylor et al., 1996) and Rocky arthropods, or a combination. Key words: Conjunctivitis, keratitis, kera- Mountain bighorn (Ovis canadensis toconjunctivitis, ocular disease, pink eye, canadensis; Meagher et al., 1992). Myco- Rangifer tarandus tarandus, reindeer, Seward plasma conjunctivae has been isolated Peninsula. from infectious keratoconjunctivitis in sheep (Ovis aries; Akerstad and Hafsha- Semidomesticated reindeer (Rangifer gen, 2004) and goats (ter Laak, 1988), tarandus tarandus) from Siberia were first alpine ( rupicapra; imported to Alaska, USA, in 1891 to serve Tschopp et al., 2005), and ibex (Capra as a food and income source for the Yup’ik ibex ibex; Mayer et al., 1996). In addition, and Inupiaq peoples. In Alaska, reindeer a variety of opportunistic bacteria have are allowed to forage freely and are been isolated from reindeer (Aschfalk et periodically rounded up with helicopters al., 2003). for slaughter, antler harvesting, and med- A primary etiologic agent causing kera- ical care (Dieterich, 1981). toconjunctivitis in reindeer has not been Alaskan reindeer herders have request- identified. Keratoconjunctivitis is reported ed assistance from state and federal in reindeer throughout Finland and Scan- agencies, including the University of dinavia, and in many other species. Alaska Fairbanks, to identify the factors Hadwen and Palmer (1922) and Dietrich responsible for decreasing productivity. (1981) have previously discussed keratitis One potential loss of productivity is as a clinical condition in Alaskan reindeer. keratoconjunctivitis in calves, a painful To our knowledge, this is the first case

1051 1052 JOURNAL OF WILDLIFE DISEASES, VOL. 44, NO. 4, OCTOBER 2008 report of keratoconjunctivitis in Alaskan 24–72 hr of collection. All samples were reindeer and the only report of kerato- subjected to routine bacteriologic testing conjunctivitis that is limited to reindeer as described by Quinn et al. (1994). Swabs calves. were inoculated into bovine turbinate cells Reindeer (2,300–3,000) were herded by and Madin-Darby canine kidney and helicopter into a corral about 8 km north Crandall feline kidney cells. Cell cultures of Nome, Alaska. Sex was determined, and were incubated at 37 C, and if cytopathic calves were tagged and weighed on a effect was not observed after three pas- platform mounted on a Tru-test livestock sages at 4-day intervals, the sample was scale (Pearson Livestock Equipment, classified as negative for virus. Thedford, Nebraska, USA). Six hundred After testing was completed at sixty calves, approximately 4–8 wk of age, WADDL, swabs were shipped to Kansas were evaluated for keratoconjunctivitis on State University, Manhattan, Kansas, 29 June, 2 July, and 14 July 2005. Each USA, for polymerase chain reaction animal’s eyes were examined macroscop- (PCR) testing for Mycoplasma spp. and ically, with the aid of a flashlight, for M. bovis. The PCR test for Mycoplasma clinical signs of keratoconjunctivitis, in- spp. was performed as described by cluding conjunctival inflammation, exces- Lauerman (1998). The M. bovis PCR sive lacrimation, squinting, corneal opacity was done by randomly amplified polymor- and/or corneal ulceration. Data were phic DNA (RAPD) PCR, using two collected on the presence of clinical signs, different sets of primers. The resulting sex and body weight. If handled more than banding patterns were compared with the once, the mean weight was used. Affected profiles of the American Type Culture animals were sampled with the next Collection (Manassas, Virginia, USA) healthy animal sampled as a control. Swab strain of M. bovis. samples were taken from the lower The eyes of 26 reindeer slaughtered conjunctival sac of each animal using during February and March 2006 were BBL Culture Swabs (Becton Dickinson, also examined. All of these animals were Sparks, Maryland, USA). Swab samples normal in appearance. were streaked onto sheep blood agar Of the 660 calves examined, 329 were plates and then stored in a culture males and 330 were females; sex was not medium composed of a mixture of brain recorded for one animal. Keratoconjunc- heart infusion broth (Difco Laboratories, tivitis, based on any one of the following Detroit, Michigan, USA), 50% sheep clinical signs was observed in 26 (3.9%) blood, and 5% glycerin. Swab samples animals. Observed clinical signs included and blood agar plates were shipped on ice conjunctival inflammation, corneal neo- to the Washington Animal Disease Diag- vascularization (3–5 mm), excessive lacri- nostic Laboratory (WADDL) in Pullman, mation, squinting, corneal opacity, corneal Washington, USA, for bacterial culture ulceration, and/or blepharospasm. Eigh- (blood agar plates), virus isolation (swabs), teen of 26 (69.2%) affected animals and enzyme-linked immunosorbent assay exhibited severe disease, including both (ELISA) testing for C. psittaci (QuickVue conjunctival and corneal signs. Twenty- ELISA test, Quidel Corporation, San two affected animals and 24 controls were Diego, California, USA; swabs). Sheep sampled. There were no ocular parasites blood agar plates that could not be observed in cases or controls. shipped to WADDL immediately were The average weight of all affected incubated at 37 C for 24 hr and then weighed animals was 26.4 kg (n523, refrigerated. Swabs in the modified trans- SD53.6). The average weight of unaffect- port media were refrigerated until ship- ed animals was 27.1 kg (n5546, SD54.6); ment. Samples reached WADDL within based on a two-sample t-test (Freedman et SHORT COMMUNICATIONS 1053 al., 2007), affected animals weighed sig- used for Mycoplasma spp. at the Kansas nificantly less than the unaffected animals State University Veterinary Diagnostic (t52.33, P,0.05). Laboratory were shown to detect and No pathogenic bacteria were grown on differentiate between 11 bovine Myco- aerobic culture. A mixed population of plasma spp. (Baird et al., 1999). Based on non–b-hemolytic bacteria, including these results it seems that Mycoplasma Staphylococcus spp., Streptococcus spp., spp. are not involved in keratoconjuctivitis and coliform bacteria, was isolated from in Alaskan reindeer calves. affected and control animals. These bac- The negative PCR results for M. bovis teria are considered of low virulence and were inconclusive because the RAPD are commonly isolated from the environ- PCR works poorly in mixed cultures, and ment and other nonsterile sites. No viruses interpretation amplification patterns con- were detected and all samples were taining DNA from multiple organisms is negative for C. psittaci, Mycoplasma difficult. However, we can reasonably rule spp., and M. bovis. out M. bovis as a primary etiologic agent Although there was a significant associ- based on the negative culture results in all ation between decreased weight and 22 affected samples. increased incidence of keratoconjunctivi- Bovine herpes virus 1 (BHV-1) or tis, a causal relationship was not con- another herpesvirus with similar antige- firmed. The observed blepharospasm in- nicity has been found in Alaskan reindeer dicates that the condition is most likely (Dieterich, 1981). In Finland, 23% of 300 painful and neovascularization indicates domestic reindeer had serum neutraliza- that the disease was present for several tion antibodies to BHV-1, but cervid days before examination (Martin, 2005). herpes virus 2 was isolated (Ek-Kommo- Because calves had been in the corral for nen et al., 1986). An outbreak of ocular 12–36 hr, these clinical signs indicate that disease in ( elaphus) the cause was present before handling. calves associated with a virus antigenically A negative ELISA test (sensitivity similar BHV-1 was reported by Inglis et al. 97.5%)forChlamydophla strongly sug- (1983). In this outbreak, conjunctivitis, gests that this organism is not involved in purulent ocular discharge, corneal opacity, the etiology of infectious keratoconjunc- and excessive lacrimation were observed tivitis in Alaskan reindeer. Negative virus in 50 to 60 of 80 calves. Of the 34 initial isolation results, however, do not rule out cases, 19 exhibited bilateral ocular signs viral involvement in this disease as some (Inglis et al., 1983). Of our 26 cases, only potential viruses’ capable of causing one exhibited bilateral keratoconjunctivi- keratoconjunctivitis in cervids or rumi- tis. It is possible that reindeer affected nants may not readily grow in cell culture with a herpesvirus or other agent that or may have been inactivated during causes bilateral lesions do not survive, but transport. at present, herpes viruses have not been The failure of bacterial culture to detect shown to cause keratoconjunctivitis in a primary pathogen indicates that the reindeer. etiologic agent is most likely not bacterial The impact of keratoconjunctivitis on or is an anaerobic or highly fastidious reindeer calf survival is unknown and bacterial agent. Our methods were de- would be difficult to assess because signed for detection of species such as M. reindeer are not consistently handled. In ovis, M. bovis, Branhammella ovis, and the addition, the role of natural is negative culture results indicate that these unknown as is the normal survival rate. species are not involved because they are Our data indicate that approximately relatively easy to isolate and identify 4% of reindeer calves 4–8 wk of age were (Quinn et al., 1994). The PCR methods affected with clinical signs of keratocon- 1054 JOURNAL OF WILDLIFE DISEASES, VOL. 44, NO. 4, OCTOBER 2008 junctivitis. We noted that there were very LITERATURE CITED few adults with corneal changes, suggest- AKERSTAD, J., AND M. HOFSHAGEN. 2004. Bacteriolog- ing that affected animals either die, as ical investigation of infectious keratoconjunctivi- reported by Aschfalk et al. (2003), or tis in Norwegian sheep. Acta Veterina Scandvia 45: 19–26. recover completely. ASCHFALK, A., T. JOSEFSN,H.STEINGASS,W.MULLER, Studies need to be conducted to better AND R. GOETHE. 2003. Crowding and winter define this clinical condition in reindeer. emergency feeding as predisposing factors for We recommend establishing a case-fatality kerato-conjuntivitis in semi-domesticated rein- rate by comparing the yearly survival of deer in Norway. Deutsche tierarztliche Wo- affected and nonaffected calves. Conjunc- chenschrift 110: 269–308. BAIRD, S. C., J. CARMAN,R.P.DINSMORE,R.L. tival cytology may help determine the type WALKER, AND J. K. COLLINS. 1999. Detection and of inflammation present and could direct identification of Mycoplasma from bovine mas- diagnostic efforts towards select categories titis infection using a nested polymerase chain of pathogens. reaction. Journal of Veterinary Diagnostic In- Identifying an etiologic agent and risk vestigations 13: 184. DIETERICH, R. A. 1981. Alaskan wildlife diseases. factors with infectious keratoconjunctivitis University of Alaska, Fairbanks, Alaska. pp. 246– will enable herders to take appropriate 247. steps for managing the disease. More DUBAY, S. A., E. S. WILLIAMS,K.MILLS, AND A. M. knowledge of this disease could lead to BOERGER-FIELDS. 2000. Association of Moraxella the development of treatments and pre- ovis with keratoconjunctivitis in and moose in Wyoming. Journal of Wildlife Diseases ventative measures, thus improving rein- 36: 241–247. deer health, limiting animal suffering, and EK-KOMMONEN, C., S. PELKONEN, AND P. F. NET- increasing production. TLETON. 1986. Isolation of a herpesvirus serolog- Funding was provided by the Geraldine ically related to bovine herpesvirus 1 from a Dodge Foundation Frontiers for Veterinary reindeer (Rangifer tarandus). Acta Veterina Scandvia 27: 299–301. Medicine Fellowship with travel and sti- FREEDMAN, D., R. PISANI, AND R. PURVES. 2007. pend support from the University of Statistics. 4th Edition. W. W. Norton, New York, Minnesota College of Veterinary Medicine New York, 578 pp. Summer Scholars Program and Class of HADWIN, S., AND L. J. PALMER. 1922. Reindeer in 2008 travel grants. The University of Alaska Alaska. USDA Bulletin No. 1089. Government Reindeer Research Program provided lo- Printing Office, Washington, D.C., 74 pp. INGLIS, D. M., J. M. BOWID,M.J.ALLAN, AND P. F. gistical and technical support. We thank the NETTLETON. 1983. Ocular disease in red deer Davis for support and for the use of calves associated with a herpesvirus infection. reindeer and all of the employees and Veterinary Record 113: 182–183. volunteers of the UAF Reindeer Research LAUERMAN, L. H. 1998. Mycoplasma PCR assays. In Program who helped collect these data and Nucleic acid amplification assays for diagnosis of animal diseases, L. H. Lauerman (ed.). Ameri- samples. B. Aschauer and J. Hiessel from can Association of Veterinary Laboratory Diag- the University of Veterinary Medicine nosticians, Turlock, California, pp. 41–43. Vienna and D. Tauer from the University MARTIN, C. L. 2005. Ophthalmic disease in veterinary of Minnesota assisted with evaluation of medicine. Manson Publishing Ltd, London, clinical signs. At the Washington Animal UK, 266 pp. Disease Diagnostic Laboratory, L. Oaks MAYER, D. J., NICOLET,M.GIACOMETTI,M.SCHMITT, T. WAHLI, AND W. MEIER. 1996. Isolation of and J. Evermann performed bacterial and Mycoplasma conjunctivae from conjunctival viral cultures, respectively. M. Hayes at the swabs of (Capra ibex ibex) affected Kansas State University Diagnostic Labo- with infectious keratoconjunctivitis. Zentralbl ratory performed the PCR for mycoplasma. Veterinarmed B 43: 155–161. N. Whelan provided valuable assistance MEAGHER, M., W. J. QUINN, AND L. STACKHOUSE.1992. Chlamydial-caused infectious keratoconjunctivitis with study design. J. Cho contributed in of Yellowstone National Park. greatly to the final manuscript by editing Journal of Wildlife Diseases 28: 171–176. and reediting. QUINN, P. J., M. E. CARTER,B.MARKEY, AND G. R. SHORT COMMUNICATIONS 1055

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