[Combat dogs--dangerous dogs]. / Kampfhunde--Gefährliche Hunde.

The claim that the so-called "Kampfhunde" are becoming increasingly dangerous to humans has been the subject of much discussion in Germany. A critical analyses of canine breeds that have been classified as "Kampfhunde" convinces that breed is not an useful possibility for avoiding accidents with dogs: 1. Zoologically no particular breed of dog can be classified as being more dangerous than others and 2. so-called "Kampfhunde" are statistically unimportend as a vector in dog accidents. It would be more productive in the future to substitute the term "Kampfhund" with "dangerous dog" without reference to the breed and to emphasize the role of the owner in the human danger posed by a dog.

[Life expectancy and cause of death in dogs. I. The situation in mixed breeds and various dog breeds]. / Lebenserwartung und Todesursachen bei Hunden. I. Zur Situation bei Mischlingen und verschiedenen Rassehunden.

The present study on life expectancy and cause of death is based upon data from 9,248 dogs. The entire sample showed a life expectancy of 10.0 years. The most frequent cause of death was tumors (27.3%), followed by cardiac and circulatory ailments (16.3%). The causes of death also showed a breed-specific distribution. The mean age attained in various breeds differed, ranging from 6.8 years in the Berner Sennenhund to 13.0 years in the Pudel. Dogs of mixed breeding tended not to differ from purebreds either in their life expectancy or in their cause of death.

[The nature of the dog--a contribution to the keeping and breeding of so-called fighting dogs]. / Das Wesen des Hundes--zugleich ein Beitrag zur Haltung und Zucht sog. Kampfhunde.

The behavioural repertoire of dogs derives from that of the wolf. But there are distinct race-specific differences which go back to the man's breeding influence in the course of domestication to develop special qualities in dogs. Today, dog keeping no longer corresponds to these qualities of dogs in many ways. We refer to the problems resulting from this and man's responsibility for the establishment of a man-dog relationship that is functional and responds to the dog's character. The abuse of certain dog behaviour by man has to be pursued consistently. In the same way we must also take care of an unforced integration of dogs into our society.

[Morphometric studies of radiographic pictures of lumbar vertebrae of healthy Boxers and Boxers with spondylosis]. / Morphometrische Untersuchungen an Röntgenaufnahmen von Lendenwirbeln gesunder und spondylosebefallener Boxer.

Length and height measurement of the third lumbar vertebra in 286 radiographs of 140 male and 146 female Boxers was carried out to defect differences between dogs with and dogs without spondylosis. No differences could be established. However, there were statistically significant differences in the length of the vertebra between male and female dogs within the age groups (below two years and above 5 years) and between bitches younger than two years and bitches older than 5 years. Length-height-proportions did not change. Female Boxers were more often affected with spondylosis than males.

[Electron microscopy studies of ciliated cells in the larval epidermis of Rana t. temporaria (L.) (Amphibia, Anura)]. / Elektronenmikroskopische Untersuchungen der Wimperzellen in der larvalen Epidermis von Rana t. temporaria (L.) (Amphibia, Anura).

Examination of the epidermis of Rana temporaria in various stages of development revealed the presence of densely ciliated cells from the late neurula until shortly before metamorphosis. Unlike the other epidermal cells, these ciliated cells do not divide; once formed, they are constant in number until they disappear. In shape, size, and structure, however, they vary depending on stage of development and on their position in the body. In older larval stages and young tadpoles they are fully differentiated and strongly basophilic. Their function is to improve the hydrodynamic properties of the larval body, and hence ultimately to optimize the energy balance during locomotion.

[Electronmicroscopic studies on the skin pigmentation of the red bellied toad Bombina bombina (L.)]. / Elektronenmikroskopische Untersuchungen zur Hautpigmentierung der Rotbauchunke, Bombina bombina (L.).

The various colours of the red-bellied toad Bombina bombina are caused by 3 types of chromatophores, the red xanthophores, the white iridophores and the black melanophores. In the brownish skin and in the black spots of the dorsal region all types of chromatophores are found. But in the epidermis of the black spots there are more grana of melanin than in the other region of the back. The 3 types of chromatophores are not present in the skin of all parts of the body. The dark blue colour of the belly is caused only by melanophores, whereas in the ventral parts with light blue colour there occur melanophores and iridophores. The white spots of the belly contain only iridophores, the red spots have iridophores and xanthophores.

Local degenerative changes in the drum muscles of piranhas (serrasalminae, characidae).

In the posterior drum muscle of the piranha structural alterations are frequently observed. Electron microscopic studies revealed a disordering of the myofibrils in these regions, accompanied by conspicuous changes in the mitochondria. As the degree of disorder increases, the mitochondrial cristae initially swell to form vesicles. Eventually the mitochondria become filled with myelin-like lamellar structures, which in many cases coalesce to form a dense outer wall. A striking concentration of lysosomes into localized masses was also characteristic of these regions.

Fine structure of the drum muscles of the piranha (serrasalminae, characidae).

The anterior and the posterior drum muscles of the piranha resemble each other in all essential fine structural aspects: myofibrils are slender; sarcomeres are short compared with those of other drum muscles; mitochondria, located in the periphery of the fibers, are numerous and show an irregular internal structure; and the sarcoplasmic reticulum is abundant. Triads appear at the level of the Z lines. The drum muscles have many motor endplates, which, however, lack the characteristic junctional-fold apparatus. No lipid substances could be demonstrated in these muscles. In the posterior drum muscle the fibers depart from their orderly longitudinal arrangement at irregular intervals.

The fine structure of the drum muscles of the tigerfish, Therapon jarbua, as compared with the trunk musculature.

The fibers of drum and trunk muscles of the Tigerfish. Therapon jarbua, differ greatly in diameter. The myofibrils of the trunk muscles are irregularly oriented, while those of the drum muscles are rolled into spiral or concentric bands. Both muscle types possess the sarcomere structure typical of cross-straited musculature. However, the myofibrils of the drum muscles differ greatly in sarcomere length and width from those in the trunk musculature. The trunk muscles contain few mitochondria, whereas in the drum muscles mitochondria are abundant. The sarcoplasmic reticulum (SR) of the drum muscles takes the form of elongated tubes in both the A and the I region; that of the trunk musculature consists of small vesicles. Of the two muscle types, the drum muscle contains more SR. With respect to the form of the T system, the trunk musculature is of the Z type and the drum muscles of the A-I type. The drum muscle displays a considerably greater number of motor endplates; these lack typical junctional folds and have mitochondria with very few cristae. No fat could be demonstrated in either the drum or the trunk muscles. However, the concentration of glycogen is higher in the drum muscles than in the musculature of the trunk.

Fat and glycogen utilization in the larynx Muscles of fire-bellied toads (Bombina bombina L.) during calling activity.

Both fat and glycogen are present in abundance in the larynx muscles of anurans. To clarify their role, the Musculus dilatator laryngis of the male fire-bellied toad, Bombina bombina was studied. In untreated males, the mean fat content of this larynx muscle was 14%; the muscle contained glycogen amounting to 57% of that measured in the liver tissue of the same animal. After thirteen days of continual calling activity induced by administration of a gonadotropin, the fat content fell to 6%, the glycogen to 34%. The fat content was essentially unchanged (13%) by four hours of electrical stimulation of the muscle; the glycogen content, however, had fallen to 42% after this treatment. Neither component was altered in amount by castration, the fat content being about 13% and that of glycogen, 52%. Nor did treatment with gonadotropic hormone reduce either the fat content (13%) or the amount of glycogen (59%). From these results it was concluded that fats represent a direct source of energy for the larynx muscles, which is used up gradually over long periods of calling. The glycogen in these muscles, on the other hand, is a short-term store sufficient to supply energy for only a few hours of calling activity.