Comparison of growth curves of mice selected and unselected for postweaning gain

Summary Mice were sampled from a line selected for increased postweaning weight gain from three to six weeks and from a randombred control line originating from the same base population. Body weights were recorded at each of 14 ages from day 5 to day 98. The Richards and logistic growth functions were fitted to the growth trajectories of each individual mouse by a generalized non-linear least squares procedure. Estimated growth parameters (asymptotic weight, rate, shape of curve, age and weight at inflection, mean absolute growth rate and mean relative growth rate) were computed for each individual. The effects of line, litter within line, sex and line × sex interactions on these estimated parameters were then studied.Both the Richards and logistic functions fitted the data equally well and the plotted trajectories coincided over most of the growth curve. There was excellent agreement between the estimates of asymptotic weight and both age and weight at inflection based on the different functions. However, both functions apparently underestimated the asymptotic weight.Analyses of the line differences showed that selection for postweaning gain increased the mean absolute growth rate over the entire curve but had no effect on the relative growth rate or the shape of the growth curve. Full-sib analyses suggested the presence of considerable genetic variation and some high genetic correlations among the estimated growth parameters.Paper number 2942 of the Journal Series of the North Carolina State University Agricultural Experiment Station, Raleigh, North Carolina. This research was supported in part by Public Health Service Research Grant GM 11546. Computing services were supported by NIH Grant FR-00011.     

Beobachtungen zur fortpflanzungsbiologie und zum verhalten der geißelspinne tarantula marginemaculata C. L. Koch (Chelicerata,Amblypygi)

The social behaviour of T. m. includes ritualized fights. Sperm transfer is achieved by means of a spermatophore deposited on the ground and by the male pulling the female over it. The behaviour and the spermatophore are described and compared to those of other arachnids and the phylogenetical implications are discussed.     

Ein überzähliger genitalapparat bei einem rhabdocölen Turbellar

A specimen of Ethmorhynchus anophthalmus Meixner 1938 contains a complex of supernumerary genital organs in front of the pharynx. The phenomenon elucidates some traits in the morphogenesis of the atrial organs.

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Abkürzungen in den Abbildungen At Atrium genitale - Bu Bursa - Ci Cirrus des Kopulationsorganes - Dc Ductus communis - Ho Hoden - Ke Keimstock - Kop Kopulationsorgan - Ph Pharynx - R Rüssel - Sa Samenblase     

The assay of acid phosphatase activity by means of a laser method

Summary A new method of quantification of the acid phosphatase activity assay by means of laser rays along with spectrography and photometry is described. Calculated S values, representing differences between densities of the spectral bands corresponding to Pb and Ag account for the amount of acP activity.The presented laser method enables a relative evaluation of the acP activity in a given region, yielding results which can be objectively expressed by figures.A special advantage of the presented method is, that it allows to compare the individual acP activities in different regions of the investigated organ, which may be of importance for the quantitative chemoarchitectonic of the brain.     

Synthese der Hämolymphproteine und die Aufnahme der Dotterfraktion in die Oocyte unter Actinomycin-Einflu\ (Untersuchungen anMusca domestica)

Zusammenfassung Mit Hilfe von autoradiographischen und elektrophoretischen Methoden wurde die Dottereinlagerung in den wachsenden Oocyten vonMusca domestica untersucht. Sie beginnt nach 30 min im Autoradiogramm sichtbar zu werden. Durch ihre Färbbarkeit und Markierung konnte die Dotterfraktion im Pherogramm von Ovar und Hämolymphe eines mittleren Wachstumsstadiums (Stadium 3) nachgewiesen werden. Nach Abschlu\ der Vitellogenese tritt sie in der Hämolymphe nicht mehr auf. Die Einlagerung der Dotterproteine wird durch Actinomycin gestört, dagegen läuft ihre Synthese nahezu unbeeinflu\t weiter. Die Transporthemmung kann als bisher unbekannter Nebeneffekt des Actinomycins gedeutet werden.

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Synthesis of haemolymph proteine and the uptake of the yolk fraction in the oocyte during Actinomycin-treatment. (Studies onMusca domestica)

Summary By means of radioautographic and electrophoretic techniques yolk protein uptake in the growing oocytes ofMusca domestica was investigated. After 30 min yolk protein becomes visible in the radioautograms. By stainability and labeling the yolk fraction could be demonstrated in the pherogram of ovary and haemolymph in an intermediate developmental stage (stage 3). After the end of vitellogenesis it does not appear in the haemolymph. The yolk protein uptake is inhibited by Actinomycin, but the synthesis goes on nearly as normal. This inhibition can be interpretated as a new accessory effect of Actinomycin.

     

Geschlechtliche organisation,fortpflanzungsverhalten und ursachen der sexuellen vermehrung von Stenostomum sthenum nov. spec. (Turbellaria,Catenulida)

Certain temperatures and H-Ion concentrations are necessary for the development of male and female reproductive organs. The differentiation of the reproductive system from undifferentiated cells conforms precisely with data on other species of Stenostomum.

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Abkürzungen in den Abbildungen b Bindegewebszelle - c Cilien - cy Cytoplasma - d Darm - de Ductus ejaculatorius - dl Darmlumen - do Dotter - dr Drüsenzellen - lr Lÿckenraum - m Mundöffnung - n Nucleolus - np Nephroporus - o Ovar - p männlicher Genitalporus - pa parenchymatischer Raum - pf periembryonale Flüssigkeit - dse dorsale Epidermis - e dorsolaterale Epidermis - ed extraembryonaler Dotter - ee Epidermiseinstülpung - eh Epidermis +Hautmuskelschlauch - em Embryo - ex Exkretvakuole - f Freßzelle - g Gehirn - ga Gehirnanlagen - gr Granula - h Hautmuskelschlauch - hz Hüzllzelle - kl Versehlußkegel/Klebkegel - in indifferente Zelle - k Kern - kdr Klebdrüsenzelle(n) - kk kollabierter Kanal - kö Körnerkolbenzelle - kp Kopulationsorgan - ku Kufen - kw Körperwand - l Lichtsinnesorgan - li Linsenkörper - lk lichtbrechende Konkremente im Darmgewebe - ph Pharynx - phr Pharynxregion - pr Zentralkanal des Protonephridialsystems - ps Präspermatide - pu Punktfeld - q Zellquartett - r Riechgruben - rh Rhombuszellenband - rhb Rhabditen - rm Radiärmuskelzelle - rhs Rhabditenschleim - rs resorbierende Darmzelle(n) - s Schale - sc Spermatocyten - se Sekretgang - t Tastborste - ta Auflösungsprodukte des Hodens - te Hoden - to Terminalorgane(e) - tz Teilungszone - v Vakuole - w vermutliches Rudiment des weiblichen Genitalporus     

Configurations resulting from iso-chromatid and iso-subchromatid unions after meiotic and mitotic prophase irradiation

Summary By making use of the chromosomes of Trillium erectum as a model, potential and actual configurations arising from presumed iso-chromatid and iso-subchromatid unions after irradiation of meiotic or mitotic prophase have been studied and analyzed. Diagrams and photographs of various recognizable types of chromatid or subchromatid rearrangements are presented. A minimum of two iso-chromatid unions within an arm of a single chromosome in meiotic prophase, if separated by a single chiasma, can give rise to a monocentric chromosome with a triplicated segment, the middle portion of which is an inversion. A minimum of two iso-subchromatid breaks within an arm at either meiotic or mitotic prophase also can result in the production of a monocentric chromosome containing a triplicated segment. The stage of appearance of dicentrics or bridges arising from chromatid or subchromatid unions in meiotic prophase is influenced by chiasma number and pattern and by the number of strands per chromosome or chromatid. Some of the rearrangements described may have genetic and evolutionary implication of considerable potential importance which has not been recognized previously.Research carried out at Brookhaven National Laboratory under the auspices of the U.S. Atomic Energy Commission.