Zur Problematik der Klimaempfindlichkeit bei Haustieren* (IX): Auswirkungen experimenteller Wärmebelastungen auf Bullen

Inhalt Die Zusammenfassung dreier vorangegangener Mitteilungen (Stephan , Lorrmann und Dycka 1971; Lorrmann , Dycka und Stephan 1971; Stephan und Dycka 1972), in denen die Veränderungen von Ejakulatqualitäten und “in-vivo” Merkmalen unter Wärmebelastungen beschrieben wurden, erfolgt durch die Gegenüberstellung dieser Wertgruppen in Korrelations- und Regressionsanalysen. Dabei ergeben sich insbesondere bei den Beziehungen zwischen Wasseraufnahme und Sauerstoffsättigung des Blutes in der unbelasteten Kontrollzeit einerseits und den Ejakulatwerten Vorwärtsbewegung, Dichte und Anteil morphologisch veränderter Spermien in der höheren Wärmebelastung andererseits signifikante Korrelationen. Ebenso finden sich zwischen der Sauerstoffsättigung des Blutes in der stärkeren Belastung und der Ejakulatdichte während und nach dieser Belastung höhere positive Korrelationskoeffizienten. Das vorliegende Material ist an nur 6 Bullen erarbeitet worden, so daβ eine (Überprüfung an gröβeren Tiergruppen notwendig erscheint. Contents The summing up of three previous communications (Stephan , Lorrmann and Dycka 1971; Lorrmann , Dycka and Stephan 1971; Stephan and Dycka 1972), in which the alterations of ejaculate qualities und “in-vivo” values under thermal loadings are described, is accomplished by the comparison of these groups of values in correlation und regression analyses. Thereby significant correlations resulted in particular from relations between the water consumption und the oxygen saturation of the blood during the nonloaded control time on the one hand und the ejaculate qualities of forward movement, density und percentage of morphologically alterated spermatozoa during the stronger thermal loading period on the other hand. In the same way higher positive correlation coefficients were found between the oxygen saturation of the blood during the stronger loading period und the ejaculate density during und after this loading These results have been achieved with only 6 bulls, so that a scrutiny in larger groups of animals seems to be necessary.     

Zur Problematik der Klimaempfindlichkeit bei Haustieren*

In a group of 6 young German Black and White bulls it was investigated whether the jollowing criteria of the ejaculate volume density total number of sperms per trial day mass motion (total) forward motion local motion proportion of morphologically alterated sperms pH value pH alteration in 5 hours can be influenced individually by thermal loading. The loadings were performed in a climatic stall over 9 days at + 30’C during daytime and + 25° C at night, and at + 35°C and + 30° C respectively. Before and after the loading periods there were normal control periods at+15°C during daytime and+12°C at night. An analysis of variance was done regarding the stress periods, the individual animals and the interactions animals to periods. Regarding the alterations by the thermal loading periods the first (weaker) one at + 30°/+ 25°C hardly proved any effect on the variables mentioned. But the second (stronger) period at + 35°/+ 30° C alterated nearly all the variables at a high degree and partially in such a manner that the starting values of the control period could not in all cases be normalized again up to 10 weaks after the loading period. Considering the intensity and duration of the reactions of the individuals there were distinct differences. Especially 2 animals in the test population were reacting outstandingly, one in a positive manner, the other particularly negatively. 12¹/₂ weeks after the loading periods, at the end of the observations the latter was still unable to regain normal values. The question whether this was a permanent defect unfortunately could not be pursued. The reaction of the other 4 animals was intermediary to the two extremes. On the basis of these and previous results it is supposed that there is a variation in the thermosensibility also within the German Black and White cattle, a factor which might be accessible as a criterion of selection.     

Zur Problematik der Klimaempfindlichkeit bei Haustieren* (V)

Contents: Following the first communication some more parameters are discussed, so as freezing and thawing resistence as well as the percentage of morphologically alterated spermatozoa after dividing them into various subunits. The freezing resistence reacts as till now the first variable with a highly significant diminution on the first weaker loading period eight days after its end. The evaluation with regard to the thawing resistence does not give any evidence over relations to sperm quality or to single sperm properties. Concerning the morphological alterations of the spermatozoa there are highly significant augmentations of the percentages of acrosomal cap, head, neck, main piece, and tail anomalies, while the middle piece and the double and multiple malformations do not reach the threshold of significance. Another arrangement of the morphological alterations shows an unimportant, nonsignificant increase of the unripe spermatozoa following the 2^nd (warmer) loading and a guaranteed increase of the percentage of primarily specific malformations. Essentially higher differences occur with the unspecific malformations, the highest and the most lasting changed variations, however, are given in the secondary malformations.     

Auswirkungen eines alimentären Zinkmangels auf die Zn-Verwertung und die Nährstoffverdaulichkeit bei zwangsernährten Ratten

In einem Stoffwechselversuch mit zwangsernährten Ratten, wurden die Folgen eines Zinkmangels bei hohem und niedrigem Futterniveau auf die Verdaulichkeit der Rohnährstoffe untersucht. Bei Depletion verschlechterten sich mit zunehmenden Zinkmangel die Verdaulichkeitswerte. Hohes Futterniveau und Zinkmangel reduzierten die Verdaulichkeitsquotienten der Trokkenmasse um 2,9, der Energie um 2,2 und des Rohproteins um 2,5 Prozentpunkte gegenüber den Kontrolltieren. Die scheinbare Verdaulichkeit des Zinks wurde durch Zinkmangel signifikant reduziert, wobei teilweise sogar negative scheinbare Verdaulichkeitsraten festgestellt werden konnten.     

Zur Frage der Umdifferenzierung der Knorpelzellen der Gelenkoberfläche am Beispiel der Synovialgrubenbildung*

It was shown both light and electronmicroscopically on cartilage of elbow and hock joints of calves and pigs that during formation of synovial fossae, fibrocytes and covering cells of the synovial layer can arise from chondrocytes.     

Licht- und elektronenmikroskopische Untersuchungen der Samenblasendrüse (Glandula vesicularis) des Bullen

Light and electron microscopical study of the vesicular gland of the bull
The vesicular glands of six adult bulls were studied grossly and with the microscope. Corrosion casts (of the duct system) examined with the dissecting microscope and the SEM clearly showed that the gland was tubulo-alveolar.
The light microscope showed two rows of tall glandular cells. The basal epithelial cells (termed "dwarf lipid-cells") contained uni- as well as plurivacuolar lipid droplets. In the tall glandular cells fine lipid droplets were seen mainly in the supranuclear cytoplasm.
Electron microscopical examinations permit division of the tall glandular cells into three compartments, shown in a semischematic drawing. The results of this study allow the conclusion that the basal "fat cells" and the peroxysomes of the tall glandular cells are related to the formation of prostaglandins.     

Der Einfluß bestimmter Elektrolyte auf die Bewegungsauslösung bei Spermatozoen der Regenbogenforelle (Salmo gairdneri)

Inhalt In Ergänzung zu vorausgegangenen Untersuchungen, den Einfluβ verschiedener Verdünnungsmedien auf die Bewegungsaktivität von Forellenspermatozoen betreffend (Holtz et al., 1977), sollte die spezifische Rolle einzelner Elektrolyte ermittelt werden. Kalium, sowohl als Chlorid wie als Karbonat, bewirkte bereits in auβerordentlich geringer Konzentration eine ausgeprägte Bewegungshemmung. Bei den Kationen Natrium, Calcium und Magnesium stellte sich dieser Effekt erst bei vergleichsweise hohen Konzentrationen ein. Der beste Aktivierungseffekt auf die Spermatozoen wurde bei Verdünnung mit NaCl-Lösung ermittelt. Zwischen Natrium und Kalium zeichnete sich eine antagonistische Wirkung ab, indem eine Lösung aus NaCl und KCl erst dann auf die Spermien bewegungsauslösend wirkte, wenn das Na: K-Verhältnis weiter als 6 : 1 wurde. Die Karbonate von Na und K führten eine charakteristische, sich deutlich von der hypotonischer Chlorid-Lösungen unterscheidende Geiβelschddigung herbei, die möglicherweise mit der Veränderung des pH-Wertes zusammenhing. Ansonsten wurde innerhalb eines weiten Bereichs kein offensichtlicher Zusammenhang gefunden zwischen pH und-osmotischem Druck einer Lösung and deren Fähigkeit, Forellenspermatozoen zu aktivieren. Contents The influence of certain electrolytes on the induction of sperm motility in rainbow trout (Salmo gairdneri). Complementing earlier studies concerning the effect of the addition of different fluids to freshly collected trout milt (Holtz et al., 1977) the specific effect of certain minerals was investigated. Activation of spermatozoa normally occurring upon dilution was found to be inhibited when the diluent contained small quantities of KCl or K₂CO₃. To obtain a similar effect using salts of sodium, calcium or magnesium, much higher concentrations were necessary. At levels below those exerting an inhibitory effect, NaCl had the most stimulatory effect on sperm motility. Sodium and potassium appear to act as antagonists. Addition of a mixture of NaCl and KCl to trout milt elicited an activating effect as soon as the Na: K-ratio was wider than 6: 1. The carbonates (Na₂CO₃, K₂CO₃) caused typical sperm tail defects quite distinct from those resulting from suspension of spermatozoa in hypotonical solutions. Possibly the shift in pH might be held responsible for these although as a whole, neither pH nor osmotic pressure seemed to have any great impact on the motility of trout sperm.     

Räumliche Anordnung und Mikrovaskularisation der Ductuli efferentes testis vom Bullen (Bos taurus)

The arrangement, origin, course and opening of the ductuli efferents testis of the bull (Bos taurus) were visualized using scanning electron microscopy. The corresponding capillary structure was also described and documented with the help of corrosive microanatomical casts. The number of the ductuli efferents testis of the bull varies narrowly between 12 to 13. Ductuli removed from the surrounding tissue have a length of up to 78 cm. The duct system is composed of linear as well as tortuous parts, permitting division into three distinct segments. Blind ending ductules are very short. We therefore do not see these structures as being associated with spermiostasis. The capillary density as well as the capillary architecture show regional peculiarities. All segments of the ductuli efferents testis are composed of capillaries of the continuous type. The findings indicate that the increased capillary density in the voluminous initial section of the ductuli efferents testis represents the basis for resorptive as well as secretory activities in the bull.