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We studied the structural characteristics and periodicities of regular incremental markings in sheep enamel using fluorochrome injections for vital labeling of forming enamel and backscattered electron imaging in the scanning electron microscope. Microscopic analysis of mandibular first molars revealed the presence of incremental markings with a daily periodicity (laminations) that indicated successive positions of the forming front of interprismatic enamel. In addition to the laminations, incremental markings with a sub-daily periodicity were discernible both in interprismatic enamel and in enamel prisms. Five sub-daily increments were present between two consecutive laminations. Backscattered electron imaging revealed that each sub-daily growth increment consisted of a broader and more highly mineralized band and a narrower and less mineralized band (line). The sub-daily markings in the prisms of sheep enamel morphologically resembled the (daily) prisms cross striations seen in primate enamel. Incremental markings with a supra-daily periodicity were not observed in sheep enamel. Based on the periodicity of the incremental markings, maximum mean daily apposition rates of 17.0 µm in buccal enamel and of 13.4 µm in lingual enamel were recorded. Enamel extension rates were also high, with maximum means of 180 µm/day and 217 µm/day in upper crown areas of buccal and lingual enamel, respectively. Values in more cervical crown portions were markedly lower. Our results are in accordance with previous findings in other ungulate species. Using the incremental markings present in primate enamel as a reference could result in a misinterpretation of the incremental markings in ungulate enamel. Thus, the sub-daily growth increments in the prisms of ungulate enamel might be mistaken as prism cross striations with a daily periodicity, and the laminations misidentified as striae of Retzius with a supra-daily periodicity. This would lead to a considerable overestimation of crown formation times in ungulate teeth.

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Oral vaccination of red foxes against rabies has been practiced in Europe since 1978 and has succeeded in greatly reducing the occurrence of this disease in foxes: this is an example of coordinated activity against a disease that affects both wild and domestic animals as well as humans. Some examples of diseases that affect both domestic and wild animals in Europe are: classical swine fever (hog cholera) in wild boars and domestic swine; myxomatosis and rabbit hemorrhagic disease in domestic and wild rabbits; bovine viral diarrhea (BVD) in cattle and roe deer; contagious ecthyma in domestic sheep and goats and also in, e.g., chamois, muskox, and reindeer; Mycobacterium bovis in cattle, wild boars, badgers, and deer; and brucellosis in a broad range of livestock and wildlife in all European countries. In addition, serological surveys performed in different free-ranging ungulate species revealed the presence of alphaherpesviruses related to bovine herpesvirus-1 in 7 European countries; and a study of malignant catarrhal fever in deer in Germany might indicate that in this case sheep are the main reservoir species. Although many data on infectious diseases are available in various European countries, there is more need for systematic surveillance and coordinated research.

A taxonomic study was performed on 13 bacterial strains isolated from preputial swabs of European bison (Bison bonasus) bulls suffering from balanoposthitis. The isolates were Gram-positive, non-motile, facultatively anaerobic, diphtheroid-shaped cells. Based on biochemical profiles and BOX-PCR-generated genomic fingerprints, the isolates were grouped into two clusters represented by four and nine strains, respectively. Strains 1(W3/01)T and 2(W106/04)T, selected as representatives of the two clusters, shared 97·2 % 16S rRNA gene sequence similarity. The highest gene sequence similarities found (95·5–96·4 %) were to Arcanobacterium pyogenes DSM 20630T and Arcanobacterium bernardiae DSM 9152T, demonstrating that the novel strains are members of the genus Arcanobacterium, but are not members of a recognized species. The polar lipid profiles of the two novel strains displayed the major characteristics also found in A. pyogenes DSM 20630T and Arcanobacterium haemolyticum DSM 20595T. Detection of a quinone system with MK-10(H4) as the predominant compound confirmed phylogenetic relatedness of the novel strains to A. pyogenes and separated them from the type species of the genus, A. haemolyticum, which contains MK-9(H4) as the predominant quinone. Results from DNA–DNA hybridizations clearly demonstrated that strains 1(W3/01)T and 2(W106/04)T represent separate species. Based on these data, two novel species of the genus Arcanobacterium are described, for which the names Arcanobacterium bialowiezense sp. nov. [type strain 1(W3/01)T=DSM 17162T=NCTC 13354T] and Arcanobacterium bonasi sp. nov. [type strain 2(W106/04)T=DSM 17163T=NCTC 13355T] are proposed.