A century of liming affects the Mg isotopic composition of the soil and crops in a long-term agricultural field at Berlin-Dahlem,Germany     

Yi Wang  Bei Wu  Anne E. Berns  Roland Bol  Frank Wombacher  Frank Ellmer  Wulf Amelung 《European Journal of Soil Science》2021,72(1):300-312

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Cortisol release,heart rate and heart rate variability,and superficial body temperature,in horses lunged either with hyperflexion of the neck or with an extended head and neck position     

M. Becker‐Birck  A. Schmidt  M. Wulf  J. Aurich  A. von der Wense  E. Möstl  R. Berz  C. Aurich 《Journal of animal physiology and animal nutrition》2013,97(2):322-330

Bringing the head and neck of ridden horses into a position of hyperflexion is widely used in equestrian sports. In our study, the hypothesis was tested that hyperflexion is an acute stressor for horses. Salivary cortisol concentrations, heart rate, heart rate variability (HRV) and superficial body temperature were determined in horses (n = 16) lunged on two subsequent days. The head and neck of the horse was fixed with side reins in a position allowing forward extension on day A and fixed in hyperflexion on day B. The order of treatments alternated between horses. In response to lunging, cortisol concentration increased (day A from 0.73 ± 0.06 to 1.41 ± 0.13 ng/ml, p < 0.001; day B from 0.68 ± 0.07 to 1.38 ± 0.13 ng/ml, p < 0.001) but did not differ between days A and B. Beat‐to‐beat (RR) interval decreased in response to lunging on both days. HRV variables standard deviation of RR interval (SDRR) and RMSSD (root mean square of successive RR differences) decreased (p < 0.001) but did not differ between days. In the cranial region of the neck, the difference between maximum and minimum temperature was increased in hyperflexion (p < 0.01). In conclusion, physiological parameters do not indicate an acute stress response to hyperflexion of the head alone in horses lunged at moderate speed and not touched with the whip. However, if hyperflexion is combined with active intervention of a rider, a stressful experience for the horse cannot be excluded.  相似文献   

Linking human activity and ecosystem condition to inform marine ecosystem based management     

Susanne Menzel  Carrie V. Kappel  Bernardo R. Broitman  Fiorenza Micheli  Andrew A. Rosenberg 《水产资源保护:海洋与淡水生态系统》2013,23(4):506-514

Vaccination mitigates the impact of PRRSv infection on the pharmacokinetics of ceftiofur crystalline‐free acid in pigs          下载免费PDF全文

J. W. Sparks  L. A. Karriker  D. N. Day  L. W. Wulf  J. Zhang  M. L. Stock  J. L. Bates  R. Gehring  J. F. Coetzee 《Journal of veterinary pharmacology and therapeutics》2017,40(4):363-369

The pharmacokinetics of intramuscularly administered ceftiofur crystalline‐free acid (CCFA) were determined in pigs that were clinically healthy (n = 8), vaccinated with a Porcine reproductive and respiratory syndrome modified live virus (PRRS MLV) (n = 10), challenged with wild‐type porcine reproductive and respiratory syndrome virus (PRRSv) VR‐2385 (n = 10), or vaccinated with PRRS MLV and later challenged with wild‐type PRRSv VR‐2385 (n = 10). Animals were given a single dose of CCFA intramuscularly at 5 mg/kg body weight. Blood was collected at 0 (pretreatment), 0.25, 0.5, 1, 6, 12, 24, 48, 96, 144, 192, and 240 h postinjection. Plasma was analyzed using liquid chromatography‐mass spectrometry. Plasma concentration–time curves for each group were evaluated with noncompartmental modeling. When compared to control animals, those receiving the PRRSv wild‐type challenge only had a lower AUC_0‐last, higher Cl/F, and higher Vz/F. The PRRSv wild‐type challenge only group had the longest T_1/2λ. The C_max did not differ among all four treatments. Control animals had no statistically significant differences from animals vaccinated with PRRS MLV alone or animals vaccinated with PRRS MLV and later challenged with wild‐type PRRSv. Our results suggest that PRRSv wild‐type infection has the potential to alter CCFA pharmacokinetics and PRRS MLV vaccination may attenuate those changes.  相似文献   

Can we influence health status and semen quality of breeding stallions by feeding a prebiotic feed additive during one breeding season?     

S.S. Pasing  N. Aldaher  M. Wulf  M. Becker-Birck  R. Erber  M. Krüger  C. Aurich 《Journal of Equine Veterinary Science》2012

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Effects of oral supplementation with β-carotene on concentrations of β-carotene, vitamin A and α-tocopherol in plasma, colostrum and milk of mares and plasma of their foals and on fertility in mares     

Kuhl J  Aurich JE  Wulf M  Hurtienne A  Schweigert FJ  Aurich C 《Journal of animal physiology and animal nutrition》2012,96(3):376-384

In this study, effects of oral β-carotene supplementation to mares (β-carotene group: 1000 mg/day, n = 15; control group: n = 15) from 2 weeks before foaling until 6 weeks thereafter on concentrations of β-carotene, vitamin A and α-tocopherol in plasma, colostrum and milk and plasma of their foals were determined. In addition, effects on fertility were studied. Beta-carotene concentrations increased in plasma and colostrum of β-carotene-supplemented mares compared to control mares (p < 0.05). In mares of both groups, β-carotene concentrations were higher in colostrum than in milk (p < 0.05). In foals, β-carotene concentrations increased with colostrum uptake and were higher in foals born to supplemented mares (p < 0.05; control group: 0.0003 ± 0.0002 μg/ml on day 0, 0.008 ± 0.0023 μg/ml on day 1; β-carotene group: 0.0005 ± 0.0003 μg/ml on day 0, 0.048 ± 0.018 μg/ml on day 1). Concentrations of vitamin A and α-tocopherol were higher in colostrum than in milk (p < 0.05) but did not differ between groups. Concentration of α-tocopherol in plasma of mares decreased over time and in foals, increased markedly within 4 days after birth. All but one mare (control group) showed oestrus within 2 weeks post-partum. Occurrence of oestrus did not differ between groups. More mares of the control group (7/7 vs. 5/12 in the β-carotene group) became pregnant after being bred in first post-partum oestrus (p < 0.05). In conclusion, β-carotene supplementation to mares increased β-carotene concentrations in plasma, colostrum and milk of mares and plasma of their foals but had no positive effects on fertility.  相似文献   

Naphthalene production by microorganisms associated with termites: Evidence from a microcosm experiment     

Benjamin A. Musa Bandowe  Marcos A.L. Bragança  Wulf Amelung  Wolfgang Wilcke 《Soil biology & biochemistry》2009,41(3):630-639

There have been several reports published which suggest that it is possible that the polycyclic aromatic hydrocarbons (PAHs) naphthalene (NAPH), phenanthrene (PHEN) and perylene (PERY) in tropical environments have a biological source. This source might be related to the activity of termites or their associated microorganisms. We aimed to provide direct evidence for the biological production of NAPH, PHEN and PERY by conducting microcosm experiments in the State of Tocantins, Brazil, in which termite nests (with or without termites) were placed in an enclosed environment in which we controlled all PAH fluxes and monitored changes of PAH stocks. The experiments were carried out with termites from a tropical floodplain forest environment at the Estação Canguçu (Ilha do Bananal) in the State of Tocantins, Brazil. We set up the following treatments: live nest of Nasutitermes cf. minor using PAH-poor wood as food (LNW), live nest of Nasutitermes cf. minor using PAH-poor corn as food (LNC), termite nest without live termites called dead nest (DNC) and dead nest with additional treatment by a combined fungicide/bactericide (FDN) in several replicates. In LNW, LNC, and DNC, there were mean increases of 43%, 21%, and 46% in NAPH stock after 20 d while the stocks of the 20 other PAHs studied did not change or even decreased. In contrast, FDN lost 20% of the NAPH stock after 20 d of the microcosm experiment because of dissipation and lack of microbial synthesis of new NAPH. In LNW and LNC, low-molecular weight PAHs (acenaphthylene to chrysene) were significantly lost at a mean percentage which was strongly correlated with the octanol-water partitioning coefficient (K_OW, r = 0.78). This was not the case in DNC and FDN. There were no indications that in the studied termite nests PHEN and PERY were produced. Our microcosm experiments suggest that NAPH can be produced by fungi and bacteria in termite mounds while all other low-molecular weight PAHs are degraded in microcosms with live termite nests. PAH degradation seems to be enhanced by the combined activity of termites and microorganisms.  相似文献   

Evaluating the point of separation, during carcass fabrication, between the beef wholesale rib and the beef wholesale chuck   总被引：1，自引：0，他引：1  

Reuter BJ  Wulf DM  Shanks BC  Maddock RJ 《Journal of animal science》2002,80(1):101-107

This study determined whether there is a logical point of value change, related to either tenderness or consumer acceptance, at which to separate the beef carcass within the rib/chuck region. Rib/chuck rolls (RCR); (n = 30) consisting of the ribeye roll and chuck eye roll subprimals (2nd through 12th rib locations) were cut into 22 steaks each (two steaks per rib location), and Warner-Bratzler shear force and consumer purchase preference were evaluated for steaks at each rib location. Steaks from different locations of the RCR were composed of differing proportions of several muscles: longissimus muscle (LM), spinalis dorsi and multifidus dorsi (SM), and complexus (CO). The LM (4th to 12th rib) contained three tenderness regions: 7th through 12th rib, 5th and 6th ribs, and 4th rib regions (lowest, intermediate, and highest shear force values, respectively; P < 0.01). Shear force differed (P < 0.05) among rib locations for the SM (2nd to 9th rib), but no logical pattern was evident. The CO (2nd to 7th rib) was more tender toward the anterior end (P < 0.05). The region of the RCR represented by the 4th through 6th rib locations had steaks with higher weighted-average shear force (average shear force of each steak, weighted for surface area of each muscle) values than the remainder of the RCR (P < 0.05). Animal-to-animal variation in shear force was 36% greater than rib-to-rib variation in shear force; thus, statistically significant differences in tenderness among rib locations may be undetectable by consumers. Steaks (n = 330) were offered for sale at a retail supermarket and case time was monitored on each steak to determine consumer purchase preference. Steaks from the 2nd through 4th rib locations required more time to sell (P < 0.01) than steaks from the 5th through 12th rib locations. Two alternative locations for the rib/chuck separation point could be between the 6th and 7th ribs, yielding a ribeye subprimal useful in marketing a "premium quality" product, or between the 4th and 5th ribs, which would yield four more 2.5-cm ribeye steaks per carcass.  相似文献   

Effects of light availability on leaf gas exchange and expansion in lychee (Litchi chinensis)     

Hieke S  Menzel CM  Lüdders P 《Tree physiology》2002,22(17):1249-1256

Effects of photosynthetic photon flux density (PPFD) on leaf gas exchange of lychee (Litchi chinensis Sonn.) were studied in field-grown "Kwai May Pink" and "Salathiel" orchard trees and young potted "Kwai May Pink" plants during summer in subtropical Queensland (27 degrees S). Variations in PPFD were achieved by shading the trees or plants 1 h before measurement at 0800 h. In a second experiment, potted seedlings of "Kwai May Pink" were grown in a heated greenhouse in 20% of full sun (equivalent to maximum noon PPFD of 200 micromol m(-2)xs(-1)) and their growth over three flush cycles was compared with seedlings grown in full sun (1080 micromol m(-2)xs(-1)). Young potted plants of "Kwai May Pink" were also grown outdoors in artificial shade that provided 20, 40, 70 or 100% of full sun (equivalent to maximum PPFDs of 500, 900, 1400 and 2000 micromol m(-2)xs(-1)) and measured for shoot extension and leaf area development over one flush cycle. Net CO2 assimilation increased asymptotically in response to increasing PPFD in both orchard trees and young potted plants. Maximum rates of CO2 assimilation (11.9 +/- 0.5 versus 6.3 +/- 0.2 micromol CO2 m(-2) s(-1)), dark respiration (1.7 +/- 0.3 versus 0.6 +/- 0.2 micromol CO2 m(-2) s(-1)), quantum yield (0.042 +/- 0.005 versus 0.027 +/- 0.003 mol CO2 mol(-1)) and light saturation point (1155 versus 959 micromol m(-2) s(-1)) were higher in orchard trees than in young potted plants. In potted seedlings grown in a heated greenhouse, shoots and leaves exposed to full sun expanded in a sigmoidal pattern to 69 +/- 12 mm and 497 +/- 105 cm(2) for each flush, compared with 27 +/- 7 mm and 189 +/- 88 cm(2) in shaded seedlings. Shaded seedlings were smaller and had higher shoot:root ratios (3.7 versus 3.1) than seedlings grown in full sun. In the potted plants grown outdoors in 20, 40, 70 or 100% of full sun, final leaf area per shoot was 44 +/- 1, 143 +/- 3, 251 +/- 7 and 362 +/- 8 cm(2), respectively. Shoots were also shorter in plants grown in shade than in plants grown in full sun (66 +/- 5 mm versus 101 +/- 2 mm). Photosynthesis in individual leaves of lychee appeared to be saturated at about half full sun, whereas maximum leaf expansion occurred at higher PPFDs. We conclude that lychee plants can persist as seedlings on the forest floor, but require high PPFDs for optimum growth.  相似文献   

Infrared Thermography of the Pig Thorax: An Assessment of Selected Regions of Interest by Computed Tomographical and Anatomical Parameters          下载免费PDF全文

A. Menzel  C. Siewert  H. Gasse  H. Seifert  D. Hoeltig  I. Hennig‐Pauka 《Anatomia, histologia, embryologia》2015,44(2):107-117

Current methods of diagnosis of respiratory diseases in swine are invasive, time‐consuming and expensive. Infrared thermography (IRT) of the thorax might provide a new method of high specificity to select swine affected with lung alterations for further diagnostics. In this study, layer thickness of different tissues was determined in frozen thorax slices (FTS) by computed tomography (CT) and then related to skin temperatures measured by IRT in healthy pigs. The aim was to determine appropriate regions of interest (ROI) for evaluation of IRT images. Organ layer thicknesses measured in CT images correspond to those measured in FTS. Temperature differences between lung ROIs and abdomen ROIs were positively correlated with lung layer thickness at certain localizations, and negatively correlated with the thickness of the thorax wall and of inner organ layers. Reference values of differences between skin temperatures were established for two ROIs on the thorax with potential practical use for lung health status determination. Respective ROIs were located on vertical lines crossing the 7th (right) and the 10th (left) thoracic vertebrae. The presence of ribs affected skin temperature significantly.  相似文献