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During december 1992 a moose cow with severely incoordinated and atactic movements was observed at several occasions in an area 20 km north of Uppsala. She was followed by a calf with normal movements and appearance. The 31 of January the cow was found laying in the forest unable to raise and walk. She was killed by means of a rifle shot in the neck and necropsied on the spot.

Farmed fallow deer suddenly developed disease showing lethargy, weakness, anorexia and several of them died. The animals showed macroscopic lesions in the digestive mucosa characterized by erosions, ulcers and necrotizing lesions. Histo-pathology of the mucous membranes revealed marked inter- and intracellular oedema, erosions, ulcers and intracyto-plasmic inclusions bodies. BVD-virus was demonstrated in 1 deer using an indirect immunofluorescence method. It is suggested that the disease may have been caused by Bovine Virus Diarrhea virus alone or in conjunction with a simultaneous infection by another unidentified virus.

Aortas of 20 reindeer, aged from 1.5 to 8.5 years, were studied. Fatty streaks were seen in 9, a fibrous plaque in 1, and elastic tissue degeneration in the tunica media in 4 of the aortas.

Calf mortality among wild and semidomesticated animals, especially reindeer, is established to be high. The authors describe a telemetric method with subcutaneously implanted transmitters which are activated by the lowered body temperature in connection with the death of the animal, enabling it to be found and brought in for pathological examination. Frequency selection, implantation technique and design of transmitter, power source, antenna and surveillance methods are discussed, with a background of commercially available equipment.

Intracytoplasmic inclusion bodies were observed in the digestive epithelium of fallow deer (Dama dama L) suffering from bovine virus diarrhea/mucosal disease. Similar inclusion bodies were also found in the ruminal epithelium of fallow deer subjected to overfeeding by supplementary food. Inclusion bodies were not found in the upper alimentary mucosa of clinically healthy deer but were frequently found when these tissues were subjected to autolysis. At electron microscopical studies the inclusion bodies were found to consist of granular protein-like material encircled by a single membrane. Such inclusion bodies may constitute a non-specific degenerative cell response which could be elicited by diverse factors including autolysis.

The ultrastructure of bovine horn cancer (squamous cell carcinoma) of Indian cattle is described. The tumour was composed of pleomorphic epithelial cells. The nuclei were enlarged with membrane invaginations and peripherally distributed heterochromatin and pleomorphic nucleoli. The cytoplasm contained bundles of tono-filaments and keratohyalin granules. In addition a majority of the cells revealed marked degenerative changes of the cytoplasmic orga-nellae and intracellular oedema. Desmosomes were rarely observed. Budding of virus-like particles from the cell membrane of a few cells was demonstrated.

Six investigations were performed in order to explore the possibility that mycoplasma, rickettsia, rickettsia-like organisms or virus can be connected with outbreaks of keratitis in reindeer. It has not been poissible in the investigations undertaken to confirm the presence of any of these organisms, indicating that they do not act as etiological agents in keratitis in reindeer.

The fine structure of the pig cornea in normal conditions and after being used in a perfusion apparatus, for 4 h, is described. Earlier reports on the normal morphology of the pig cornea were partly not confirmed. Thus the number of cell layers in the epithelium was found to be 19-23 (a basal cell layer, 4–5 polyhedral cell layers and 14–17 squamous cell layers) compared to earlier reported 6–9 layers. The mean thickness of normal and perfused corneas were 722 μm and 752 μm respectively. Normal corneas had a hydration level of 77.2 % and after perfusion 78.5 %. The normal morphology and morphological changes due to exposure to perfusion were studied by light and electron microscopy. The differences observed between normal and perfused corneas have to be considered limited, and restricted mainly to the anterior squamous epithelium and the endothelium. Taken together our results indicate that the corneas used in the apparatus still had functional integrity.

During the first 5 months of 1985, 35 moose were obtained for necropsy at the National Veterinary Institute, Uppsala, Sweden. 17 (49 %) of these cases were found to be infected with Elaphostrongylus sp. The nematodes were found in the epidural space of the spinal cord and brain, around and in the sciatic nerves and in muscle fasciae. Predilection sites appeared to be near cauda equina and the fasciae of the thoracic, gracilis and sartorius muscles. Most of the infected animals were calves. Both sexes were equally represented. Pathological changes found were characterized by focal haemorrhages and oedema. The changes were present in the muscle fasciae and in the leptomeninges of the brain and spinal cord. Beside infiltrates of mainly lymphocytes and plasma cells, adult nematodes, larvae and eggs were observed. Cases with mild gliosis in the cerebrum and degenerative changes of peripheral nerve roots affecting the epi- and perineurium were also found. In one case the inflammatory changes reached the endoneurium of a sciatic nerve bundle and in another case into a ganglion. Inflammatory reactions against the parasite were mainly directed towards eggs. In loose connective tissue close to nerve tissue in the central nervous system larvae were found close to eggs and remains of eggs indicating that eggs may hatch at this site. This investigation shows that natural infections with Elaphostrongylus sp. occur in wild moose and may produce pathological changes in large peripheral nerves and in the central nervous system.

Biopsy material of the ileum and corresponding mesenteric lymph nodes from 10 naturally infected goats was studied. In ileum a loss of epithelial cells and infiltration of epitheloid cells, macrophages and a low number of lymphocytes, plasma cells and occasional eosinophils were seen. Ultrastructurally, the epithelial cells showed degenerative changes. Epitheloid cells were characterized by a large nucleus and a wide cytoplasm rich in free ribosomes. Macrophages had been fixed in the process of engulfing bacteria or contained bacteria in phagosomes and phagolysosomes. Large phagolysosomes were common. In macrophages with many or large phagolysosomes, few or no lysosomes were observed. Degenerative changes were seen in macrophages containing many bacteria. Degenerative changes of capillary endothelium were observed. The intercellular spaces were distended by oedema and contained cell debris. The mesenteric lymph nodes were infiltrated with epitheloid cells and macrophages. The ultrastructural picture of these cells was almost identical to that of the ileum. The differences between the changes found in naturally infected and experimentally infected animals are discussed. It is concluded that the mode of infection, the number of bacteria to which the animal is exposed and the intervals between events of exposure may play a role.

In reindeer, subjected to stress, marked changes were found in some blood constituents when compared with unstressed animals, i.e. the white blood cell composition, Cortisol and urea values. Mental stress, due to handling appears to be of great importance in reindeer. Elevated urea values in stressed animals may cause a decreased meat quality.

The significance of the presence of 1st instar larvae of the reindeer nostril fly (Cephenomyia trompe L) in the conjunctival sac of reindeer was investigated. The influences of natural ultraviolet radiation upon the development of inflammatory reactions of the eyes was also studied. It is stated that both 1st instar larvae of the Cephenomyia fly, when deposited on the eye, and natural ultraviolet radiation may act as predisposing or enhancing factors in the etiology of keratitis in reindeer. In certain cases keratitis may develop when both parameters are present.

In forest reindeer of northern Sweden outbreaks of keratitis regularly appear in the height of summer in connection with marking of the calves. In forest reindeer conjunctival and corneal lesions, primarily due to foreign bodies and trauma, are found in abundance. In addition, large amounts of different bacteria are present in the conjunctival sacs of clinically healthy as well as diseased animals. It is suggested that the abundance of bacteria and the conjunctival and corneal lesions primarily are a result of the herding conditions of the forest reindeer, and furthermore that they cooperate as etiological factors in the development of keratitis.

Peripheral blood plasma levels of progesterone were studied in pregnant and non-pregnant reindeer. Marked differences in progesterone levels were found between pregnant and non-pregnant animals indicating that the determination of progesterone could be used as a pregnancy diagnosis test in reindeer.

Keratitis in reindeer (Bergman 1912) appears during the summer season, sometimes in the late spring but more frequently in the height of the summer, rather regularly in parts of the reindeer herding areas in the northern parts of Scandinavia, USSR, and North America.

The fine structure of the reindeer cornea in normal conditions and in spontaneous keratitis was described. There were more layers of squamous and fewer layers of polyhedral cells than in pigs, cattle and horses. Mild cases of corneal opacity just had some swollen superficial epithelial cells. When fully developed the keratitis had all the characteristics of an acute inflammation. Swelling or shrinking of the epithelial cells with or without degenerative nuclear changes were common. A striking alteration of the epithelial cells was the irregular appearance of the filaments which was frequently observed. In some cases there was pronounced intercellular oedema with desquamation of the superficial squamous cells and occasional neutrophils in the intercellular space. The stroma was the site of oedema, infiltration of leukocytes and vascularization. The aetiology and pathogenesis of the disease are not yet established but experimental research on these problems is in progress.