The reproductive function in experimentally-produced monozygotic twin bulls

Reproductive functions were evaluated in 12 experimentally derived monozygotic cattle twins (6 pairs). In 4 twin pairs GnRH (20 micrograms Receptal i.m.) was administered in monthly intervals from 6 through 12 months of age. LH-secretion was determined by radioimmunoassay up to 6 hours after the GnRH-challenge in hourly collected peripheral blood samples. In 5 twin pairs (age 14 to 20 months) semen was collected 5 times and processed for cryoconservation. In fresh and in frozen-thawed semen samples sperm motility was determined by means of a computerized system. Twins showed a remarkable uniform response to the GnRH-challenge. One set of twins (HF-breed) had a significantly reduced response compared to the other pairs (DFV-breed). Both individuals of this particular pair had a low percentage of progressively motile spermatozoa. In pairs with physiological sperm motility, variance of this parameter within pairs and between pairs was not different. In contrast, twin uniformity concerning the average velocity of motile spermatozoa was high; differences between set of twins explained most of the total variance. According to this study, reproductive parameters in monozygotic cattle twins are strongly influenced by twin uniformity.     

Fluorometrische Beurteilung der relativen SO2-Resistenz von Fichte (Picea abies [L.] Karst.) anhand niedermolekularer Metabolite aus Nadelextrakten

Fluorometric examination of the relative insistence to SO₂ of Norway spruce (Picea abies [L.] karst.) using low molecular metabolites from needle extracts. Relatively resistant and “normal” spruce grafts were shown by a fluorometric method to possess different concentrations of fluorescent needle metabolites. The described method could be useful in verifying resistence qualities of Norway spruce.     

Einfluß der ein- und beidseitigen Ovariektomie sowie der Injektion von Inhibin-Rohextrakt aus Bullenseminalplasma auf den Verlauf der FSH-und LH-Blutplasmakonzentrationen beim Rind

Es wurden der Einfluß der einseitigen Ovariektomie auf das verbleibende Ovar und der Einfluß der ein- und beidseitigen Ovariektomie sowie der Injektion von Inhibin-Rohextrakt aus Bullenseminalplasma auf die FSH- und LH-Blutkonzentratio-nen bei weiblichen Rindern untersucht .
1. Die einseitige Entfernung des Corpus-luteum-tragenden Ovars führt ru keiner Beein-flussung der durchschnittlichen Zykluslänge und Brunstdauer. Das Gewicht brw. das Volumen der verbleibenden Ovarien nahmen um 6 bzw. 8 % zu. Die durchschnittliche Zahl der Follikel mit einem Durchmesser über 5 mm nahm von 1 auf 2,8 Follikel zu .
2. Sowohl nach der Semikastration als auch nach der Entfernung des zweiten Ovars kam es zu einem deutlichen Ansteigen der FSH- und LH-Konrentrationen, wobei jedoch der Anstieg des FSH im Vergleich ru LH zeitlich verrögert war .
3. Die Injektion von Inhibin-Rohextrakt in 3 verschiedenen Dosen führte bei einer von 3 ovariektomierten Kühen zu einem deutlichen Absinken der FSH-Konrentratio-nen, währenddessen die LH-Konzentrationen unbeeinfluβt blieben .     

Dissipation rates of insecticides in six minor vegetable crops grown on organic soils in Ontario,Canada

Dissipation rates of diazinon, endosulfan, leptophos, methamidophos, methomyl, parathion and pirimicarb were studied on five minor vegetable crops, including cos and head lettuce, endive, cauliflower and Chinese cabbage. Residues from foliar treatment generally followed an exponential rate of decline. The number of days for residues to drop to below acceptable tolerances was highly dependent on the magnitude of the initial residue; large variations in initial residues were observed between years, between insecticides, and between crop types. Residues of five insecticides and two fungicides used in furrow treatments for onions intended for pickling were determined in the onions at harvest and after pickling. Fensulfothion and fonofos levels were below the accepted tolerance of 0.1 mg kg^?1 at harvest, while chlorfenvinphos, chlorpyrifos and ethion were present above this level; fungicide residues were not detected. Following pickling, only ethion residues were still present in the onions at levels greater than 0.1 mg kg^?1.     

Gamma Glutamyl Transferase in domestic animals

In domestic animals, Gamma Glutamyl Transferase is mainly in the kidneys, the pancreas and the intestine; its liver activity is relatively high in cows, horses, sheep, and goats and very low in dogs, cats and birds. The use of plasma reference values can help to interpret the variations of serum GGT mainly in hepatobiliary diseases of cattle, sheep, goats and cholestatic disorders of dogs. Urinary GGT is a good test of kidney toxic damage.