Abstract:The effects of brucebbosis in 60 mature elk (Cervus canadensis) and over 72 of their offspring were determined over a 65-month period.

for their support, advice, and goodwill, which has continued unabated since I embarked on my Ph.D., and without which I would have lost my bearings long ago. Like the navigators who are the focus of this thesis, I have often reassessed my position and my outlook, and have made various changes of direction during my journey over the past five years, and here again I must acknowledge the help of all of those guides whose local knowledge, whether academic or geographic, has helped me to steer my course, and whose hospitality has greeted me at various ports of call: Chris Cassels, Dr. Betsy Gebhard, John and family in Emborio (Chios), Niko Laos and family in Athens and in the Mani, Ian Morrison, Haydar Namli, the Odyssey flotilla, Bill Phelps, Rob Schumacher, Ann Thomas, and all those other friends who have made my time in Edinburgh and in Greece so rewarding. In addition I am grateful to the administrators of the Hector and Elizabeth Catling Bursary, and of the George C. Scott Fund, without whose help my visits to Greece would have been far shorter and far fewer.

Incidence of brucellosis in elk (Cervus canadensis) on two winter feedgrounds in Wyoming was examined over a 5-year period by testing serum samples using the standard plate agglutination (SPT) buffered Brucella antigen (BBA), rivanol (Riv) and complement fixation (CFT) tests. Thirty-one percent of 1,165 elk were positive by defined criteria. Considering each test individually, only 29% (106) of 370 positive sera would have been classified as reactors by the SPT, 83% (307) by the BBA test and 86% (314) by the Riv test. The CFT would have identified 85% (267) of 332 positive samples on which it was used. Brucella abortus, type 1, was isolated from 17 of 45 elk necropsied. The SPT identified 59% (10) of these as reactors, the BBA test 94% (16) and the Riv test 88% (15). The CFT identified nine of nine (100%) on which it was used. Prevalence of sero-positive animals increased with age. Brucellosis has been present in one of the two elk herds since at least 1930, and the incidence of infection among mature females in both herds was approximately 50% during this study. No single serologic test should be relied upon to diagnose brucellosis in elk.

Trypanosoma cervi sp. n. is described from 22 trypomastigote syntypes from the blood of elk, Cervus canadensis, in North America (type locality: Wyoming). The blood trypomatigotes of T. cervi are compared with various culture forms: epimastigotes in 22 to 25 C NNN cultures; trypomastigotes in 37 C NNN cultures; and trypomastigotes from CAM chick embryo (10-day) cultures. Trypanosoma cervi is differentiated on morphological grounds from the cosmopolitan bovine species, T. theileri, and from T. ingens and T. mazamarum. Transmission of T. cervi to cattle was attempted using infected elk blood. No trypanosomal stages were recovered when recipients were examined by blood culture. The findings support the morphological data that T. cervi is distinct from T. theileri.

Twenty-nine (64.4%) of 45 reindeer, Rangifer tarandus, examined over a two-year period were infected with trypanosomes. Trypomastigotes and dividing epimastigotes were found in the blood of fawns, cows, and bulls. Morphometric analysis of bloodstream trypomastigotes from reindeer and comparison of these parasites with similar stages of trypanosomes from elk, mule deer, and white-tailed deer from the contiguous United States proved them conspecific; the trypanosomes from these members of the Cervidae are identified as Trypanosoma cervi Kingston & Morton, 1975. This is the first report of trypanosomes from reindeer. No pathogenic effects are known to be caused by these parasites. RYPANOSOMES have never been reported from reindeerReceived 10 VI 81; accepted 7 V 82