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Mineralization of carbon and nitrogen from cowpea leaves decomposing in soils with different levels of microbial biomass 总被引:2,自引:0,他引:2
Kathrin Franzluebbers Richard W. Weaver Anthony S. R. Juo Alan J. Franzluebbers 《Biology and Fertility of Soils》1995,19(2-3):100-102
Soils with greater levels of microbial biomass may be able to release nutrients more rapidly from applied plant material. We tested the hypothesis that the indigenous soil microbial biomass affects the rate of decomposition of added green manure. Cowpea (Vigna unguiculata L.) Walp.] leaves were added to four soils with widely differing microbial biomass C levels. C and N mineralization of the added plant material was followed during incubation at 30°C for 60 days. Low levels of soil microbial biomass resulted in an initially slower rate of decomposition of soil-incorporated green manure. The microbial biomass appeared to adjust rapidly to the new substrate, so that at 60 days of incubation the cumulative C loss and net N mineralization from decomposing cowpea leaves were not significantly affected by the level of the indigenous soil microbial biomass. 相似文献
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White J Taylor SM Wolfram KL O'Conner BP 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(9):931-934
A 10-week-old, male, border collie-cross puppy was examined for an acute onset of unilateral vestibular signs. Neurologic deterioration was rapid over the next 12 hours and the puppy was euthanized. Rabies was diagnosed by histopathologic and immunohistochemical examination. 相似文献
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Engelhardt A Stock KF Hamann H Brahm R Grussendorf H Rosenhagen CU Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2007,120(11-12):490-498
Genetic parameters were estimated for prevalences of primary cataract (CAT), persistent pupillary membrane (PPM) and distichiasis (DIST) in 615 single-colored and 617 multi-colored English Cocker Spaniels (ECS) bred in the German kennel club for Spaniels (Jagdspaniel-Klub e.V.). CAT or CAT diagnosed in dogs up to three and a half years of age (early-onset cataract, CAT-early) and CAT diagnosed in dogs over three and a half years of age (late-onset cataract, CAT-late), PPM and DIST were included as binary traits in multivariate genetic analyses. Heritabilities on the underlying liability scale were 0.15 for CAT, 0.34 for CAT-early, 0.13 for CAT-late, 0.46 for PPM, and 0.62 for DIST in single-colored ECS and 0.06 for CAT, 0.13 for CAT-early, 0.14 for CAT-late, 0.10 for PPM, and 0.61 for DIST in multi-colored ECS. There were indications for a different genetic basis of CAT-early and CAT-late in single-colored ECS as genetic correlations were close to zero. In multi-colored ECS, a similar tendency for CAT-early and CAT-late could be observed. 相似文献
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Maike HEPPELMANN Karoline KRACH Lars KRUEGER Philipp BENZ Kathrin HERZOG Marion PIECHOTTA Martina HOEDEMAKER Heinrich BOLLWEIN 《The Journal of reproduction and development》2015,61(6):565-569
The objective of this study was to examine the effects of metritis and subclinical hypocalcemia on reduction
of uterine size in dairy cows using ultrasonography and sonomicrometry. Four piezoelectric crystals were
implanted via laparotomy into the myometrium of the pregnant uterine horn of 12 pluriparous Holstein Friesian
cows 3 weeks before the calculated calving date. Sonometric measurements were conducted daily from 2 days
before parturition (= Day 0) until Day 14 after calving and then every other day until Day 28. Distances
between adjacent crystals were expressed in relation to reference values obtained before calving. The diameter
of the formerly pregnant uterine horn was measured using transrectal B-Mode sonography starting on Day 10.
Cows were retrospectively divided into the following groups: cows without metritis (M–; n = 7), cows with
metritis (M+; n = 5), cows with normocalcemia (SH–; Ca > 2.0 mmol/l on Days 1 to 3; n = 5) and cows with
subclinical hypocalcemia (SH+; Ca < 2.0 mmol/l in at least one sample between Days 1 and 3; n = 7).
Metritis did not affect (P > 0.05) sonometric measurements, but the diameter of the formerly pregnant horn
was larger (P ≤ 0.05) between Days 15 and 21 in M+ cows than in M‒ cows. Reduction in uterine length in
hypocalcemic cows was delayed (P ≤ 0.05) between Days 8 and 21 compared with normocalcemic cows, but the
uterine horn diameter was not related to calcium status. In conclusion, both diseases affected reduction of
uterine size until Day 28. Cows with metritis had a larger uterine diameter, possibly attributable to
accumulation of lochia, and cows with subclinical hypocalcemia had delayed reduction of uterine length,
presumably related to reduction of myometrial contractility. 相似文献
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Inadequate delivery of nutrients results in intrauterine growth restriction (IUGR), which is a leading cause of neonatal morbidity and mortality in livestock. In ruminants, inadequate nutrition during pregnancy is often prevalent due to frequent utilization of exensive forage based grazing systems, making them highly susceptible to changes in nutrient quality and availability. Delivery of nutrients to the fetus is dependent on a number of critical factors including placental growth and development, utero-placental blood flow, nutrient availability, and placental metabolism and transport capacity. Previous findings from our laboratory and others, highlight essential roles for amino acids and their metabolites in supporting normal fetal growth and development, as well as the critical role for amino acid transporters in nutrient delivery to the fetus. The focus of this review will be on the role of maternal nutrition on placental form and function as a regulator of fetal development in ruminants. 相似文献
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