The outer morphology of the surface of the ependymal lining of the plexus choroideus was studied within the whole ventricular system of the brain in adult sheep using a scanning electron microscope. The more abundant occurrence of spherical secretory protrusions was found on the plexus choroideus (PCH) in the lateral cerebral ventricle. A frequent finding of the macrophagelike epiplexal cells was recorded on the PCH in the region of the lateral as well as the fourth ventricle. No differences were found in the structure of the PCH surface, which could be related to the sexual differentiation of the sheep. Our results are compared, above all, with those found in the adult goat and in the foetuses of both species of small ruminants. Central nervous system, plexus choroideus, cerebral ventricles, adult sheepLess attention has been paid to the study of the plexus choroideus as one of the structures of the ventricular system of the brain in different species of mammals using the scanning electron microscope than to the structure of the surface of the ependymal lining. In the prenatal but also in postnatal period, the surface of the PCH in laboratory rodents was observed by Yamadori (1972), Hosoya and Fujita (1973), Chamberlain (1974), Peters (1974), Mestres and Breipohl (1976), Peters and Swan (1979), in the dog (Allen 1975;Persky 1980), in the cat (Clementi and Marini 1972), in the rhesus macaque (Ling 1983), and in humans (Scott et al. 1972(Scott et al. , 1974Otani and Tanaka 1988, O'Rahilly andMüller 1990). In farm mammals the PCH was studied in the goat and sheep foetuses but also in the adult goat (R ajtová 1997, 2000). There is no record of the structure of the surface of epithelial cells that cover the PCH in adult sheep.The aim of the work was to describe the epithelial surface of the PCH in the lateral, third and fourth cerebral ventricles in adult sheep with the aid of a scanning electron microscope. Materials and MethodsTen healthy adult sheep (5 ewes and 5 rams) were used. The animals were killed in March and October by exsanguination following thiopental anaesthesia. Immediately after exsanguination, the heads of the animals were perfused through the a. carotis communis with 0.2 mol/l phosphate buffer solution and prefixed with Karnovsky solution. The specimens of the individual parts of the plexus choroideus were postfixed in 3% glutaraldehyde in 0.2 mol/l cacodylate buffer. The temperature of the solutions was 4 °C, pH 7.4. The specimens were processed by the method of Murakami et al. (1977), dehydrated, dried by the critical point method and coated with gold in vacuum. Then they were studied in the Tesla BS 340 scanning electron microscope with image analysis. ResultsThe plexus choroideus ventriculi lateralis forms low folds. The periphery of the ependymal cells is irregularly round, almost elongated. The apical membranes of most lining ependymal cells are convex, covered with thick, short, densely arranged microvillus-like structures. Among them on numerous sites are abundant, predominantly small and...

The surface of plexus chorioideus of the fourth, third and lateral ventricle and in the region of the foramen interventriculare of adult goats of both sexes was studied using scanning electron microscopy. It was found that the convex apical membranes on the whole surface of the plexus chorioideus are covered with microvilli or microvillus-like structures. The presence of cilia was not recorded. Abundant spherical protrusions occurred in the region of lateral cerebral ventricle, and were almost absent in the region of the foramen interventriculare. The epiplexal cells occurred in the fourth and lateral ventricle only sporadically; they could be seen in higher number in the third ventricle and in the region the foramen interventriculare. Some epiplexal cells had a large number of filiform processes; most of these macrophage-like cells had only 3-5 pseudopodia with "ruffled" membranes. No differences which would be connected with sex or season were found in the structure of the plexus chorioideus.

Rajtová V., J. Danko: Vasculature of testis, epididymis and ductus deferens of Rabbit. The Arteries. Acta Vet. Brno 2001, 70: 3-7.The vasculature of the testis, epididymis and ductus deferens was studied in twenty adult rabbits using X-ray apparatus. For filling the roentgen-contrast and also colour-contrast mass we used red lead in 10 % warm gelatin. We found an irregular origin of the bilateral aa. testiculares from the aorta. The testicular artery forms, after its pars recta, the pars convoluta with 13-20 loose loops inside the entire inguinal canal. It enters the parenchyma, then encircles the testis twice under the tunica albuginea. The r. rete testis is one of the intratesticular branches, which passes through the mediastinum testis. The rr. interlobulares originate from the r. rete testis. The epididymis is supplied by rr. epididymales (cranialis, media and caudalis) and the a. epididymalis caudalis. The spermatic duct is vascularized by the a. ductus deferentis originating from the common trunk of the a. iliaca externa. The cremaster muscle supplies the branches of the a. cremasterica and r. cremastericus from the a. ductus deferentis. Several intratesticular anastomoses were found between the parenchymal part of the a. testicularis and the rr. epididymales and also the a. epididymalis caudalis. Our study complets the arterial vasculature of the testis, epididymis and ductus deferens of rabbit. Arteries, testis, epididymis, spermatic duct, rabbitLaboratory animals have been, but also will be, appropriate subjects for those experiments that cannot be carried out in vitro. Some attention has already been paid by several authors to the structure of their bodies and organ systems (McLaughlin 1972;Barone et al. 1973;Cooper and Schiller 1975;Hebel and Stromberg 1976;Smallwood 1992;Popesko et al. 1992) but many details have not yet been studied.The study of anatomy, including the vasculature of the testis in domestic mammals, is closely connected with their reproduction. Similarly, in laboratory animals such study is necessary for experiments which, to a greater or lesser degree, provide knowledge which could be applied not only to domestic mammals, but also to man. Examples include the study of the effect of heavy metals on the testicular parenchyma, the effect of ionizing radiation, the effect of some medicaments, disorders in the circulation of the blood, as well as various experimental surgical interventions.Among laboratory animals, perhaps the vascularization of the rat testis has been studied the most ( H a r r i s o n 1949; H a r r i s o n and W e i n e r 1949; K o r m a n o 1967; V r z g u l o v á and Hajovská 1968;Hebel and Stromberg 1976;Chubb and Desjardins 1982;Melman et al. 1985). This problem has been studied, to a much lesser degree, in the mouse (Harrison 1949;Harrison and Weiner 1949;Froud 1959;Suzuki 1982;Chubb and Desjardins 1982), the guinea pig (Cooper and Schiller 1975), the golden hamster (Michel 1959) and in the rabbit (Harrison 1949;Harrison and Weiner 1949;Chubb and Desjardins...

Rajtova V.: Chorioid plexus in Sheep and Goat: a Scanning Electron Microscopy Study of the Foetuses. Acta vet. Bmo 1997,66: 199-202.The surface of the chorioid plexus in sheep and goat foetuses from day 62 to 145 of their foetal development was studied using the scanning electron microscope. No changes were found in the structure of the chorioid plexus surface in sheep and goat foetuses in relation to their age or gender. The chorioid plexus surface was covered predominantly with microvilli, sporadic short cilia or their clusters, which often occurred in the fourth cerebral ventricle: Secretory protrusions in the lateral and third cerebral ventricle were rare, but the occurrence of epiplexus (supraependymal) cells at these sites was abundant. There were abundant secretory protrusions on the surface of the fourth cerebral ventricle unlike the other parts of the ventricular system of the brain. However, epiplexus cells did not occur at this site.

Zusammenfassung Postnatale Entwicklung dcs Extremitätenskeletts bei Sdiaf und Ziege Bei der Ziege wadisen die langen Knochen gleichmäßiger und schließen sich die Epiphysenspalten früher als beim Sdiaf. Bei ihr ist audi der Geschlechtsdimorphismus ausgeprägter. Allgemein haben die Männchen längere und breitere Knochen, und einige Epiphysen können bei ihnen später als bei den Weibchen schließen. Zweimal fand sich bei der Ziege ein unpaares Os sesamoideum in der Ursprungssehne des lateralen M. gastrocnemius. Trächtige Tiere wiesen keine makroskopischen Veränderungen der Symphysis pelvis auf. Summary Postnatal development of the bones of the limbs in sheep and goat The long bones of the goat grow more evenly, and the epiphyseal cartilages disappear sooner, than in the sheep. Sexual dimorphism is also more marked in the goat. The males generally have longer and wider bones and some epiphyseal cartilages may close later in the males than in the females. In the goat, a unilateral sesamoid bone was found twice in the origin of the lateral head of the gastrocnemius. Pregnant animals did not show any gross changes in the pelvic symphysis. Résumé Développement postnatal du squelette des extrémités chez le Mouton et la Chèvre Chez la Chèvre, la croissance des os longs est plus régulière et les épiphyses se soudent plus tôt que chez le Mouton; le dimorphisme sexuel est aussi, chez elle, plus accuse. En général, les mâles ont des os plus longs et plus larges et quelques épiphyses peuvent, chez eux, se souder plus tard que chez les femelles. Par deux fois, on a trouvé, chez la Chèvre, un Os sesamoideum impair dans le tendon d'origine du M. gastrocnemius latéral. Les sujets gestants n'ont présenté aucune modification macroscopique de la Symphysis pelvis. Resumen Desarrollo postnatal del esqueleto de los miembros en oveja y cabra En la cabra, los huesos largos crecen de una manera más uniforme que en la oveja y los cartílagos de conjunción desaparecen más temprano, siendo tambíen el dimorfismo sexual más destacado. En general, los machos tienen huesos más largos y anchos y algunas epífisis se unen a la diáfisis más tarde que en las hembras. Dos veces se encontró en la cabra un hueso sesamoideo impar el el tendón de origen del M. gastrocnemio lateral. Animales preñados no mostraron cambios macroscópicos en la sinfisis pelviana.