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11.
Significance of microbial biomass and non-exchangeable ammonium with respect to the nitrogen transformations in loess soils of Niedersachsen during the growing season of winter wheat. I. Change of pool sizes Nitrogen transformations in loess soils have been examined by laboratory and field experiments. After straw application (· 8 t · ha?1), N in microbial biomass (Nmic) increased by about 20 mg · kg?1 soil (· 90 kg N · ha?1 · 30 cm?1) after 9 days of incubation (20 °C). Another laboratory experiment yielded an increase of about 400 mg of NH4+-N · kg?1 fixed by minerals within 1 h after addition of 1 M NH4+-acetate. Defixation of the recently fixed NH4+ after addition of 1 M KCl amounted to only 60 mg · kg?1 within 50 days. In a field experiment with winter wheat 1991, an increase in Nmic of about 80 kg N · ha?1 · 30 cm?1 was observed from March to June. After July, growth of the microbes was limited by decreased soluble carbon concentrations in the rhizosphere. Different levels of mineral N-fertilizer (0, 177 and 213 kg N · ha?1) did not affect significantly the microbial biomass. The same field experiment yielded a decrease of non-exchangeable ammonium on the “zero”-fertilized plot in spring by 200 kg N · ha?1 · 30 cm?1. The pool of fixed ammonium increased significantly after harvest. After conventional mineral N-fertilizer application (213 kg N · ha?1). NH4+-defixation was only about 120 kg N · ha?1 · 30 cm?1 until July. 相似文献
12.
Huth C Russke A Alsleben B Hamann H Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(7-8):316-326
In 58 female calves of the three breeds German Holstein (GH), German Brown (GB) and German Red (GR) the body weight and height were determined at the age of 79 to 188 days. At the right front limb and the left hind limb the following claw measurements were taken: dorsal border length, diagonal length, heel length and height, angle of the dorsal border and hardness of the claw horn. Furthermore, the punctual pressure under the medial and the lateral claw of the right front limb and the left hind limb were determined using an electronic measuring system. The GH calves weighing 136.8 kg were heavier than GB, which was the tallest breed with 106.2 cm height at the sacral bone. GR calves were the smallest (99.1 cm) and weighed 121.1 kg. The length of the diagonal and the angle of the dorsal border were smaller at the hind limb of all breeds which resulted in a smaller area of ground surface for the claw of this limb. The GR calves had the longest and flattest claws. The GB showed the highest pressures per cm2 at the front limb with 25.6 N/cm2 under both claws as well as at the hind limb with 26.7 N/cm2. The AR had the smallest pressure load with 20.8 N/cm2 at the front limb and 20.2 N/cm2 at the hind limb. The animals showed a larger relative weight load and area of ground surface on the medial claws of the front and hind limbs than on the lateral claws. The highest pressures were found underneath the rear part of the medial claw in all breeds. GB calves showed the highest average pressures (33.3 N/cm2 at the front limb) while GR calves had the lowest (26.3 N/cm2 at the hind limb). GR calves had the highest claw hardness at all measuring positions. 相似文献
13.
Ewers C Lübke-Becker A Bethe A Kiebling S Filter M Wieler LH 《Veterinary microbiology》2006,114(3-4):304-317
To learn more about the molecular biology of Pasteurella multocida 289 strains isolated from various clinically healthy and diseased hosts were examined for capsule biosynthesis genes (capA, B, D, E, and F) and 14 virulence associated genes by PCR and DNA-DNA-hybridization. As expected, capsule type A strains were highly adapted to bovines (92.3%) and poultry (85.7%) while we mainly found capA (34.9%)- and capD (58.1%)-positive strains in swine. A noticeable amount of capD-positive strains also originated from small ruminants (34.9%) and capF was detected in wild type strains from diseased cattle (2.2%) and cats (7.4%). None of the isolates harboured capE, while capB was exclusively found in all strains from buffaloes. Nearly all isolates showed a combination of genes encoding outer membrane proteins, colonization factors, iron aquisition factors and superoxid-dismutases without any clue for host specificity. In contrast, the transferrin binding protein encoding gene tbpA (31.5%) was limited to ruminant strains and only 37.0% of all P. multocida strains harboured pfhA, coding for a filamentous hemagglutinin, supposed to be a putative adhesion- und serum resistance factor. PfhA revealed a strong positive association to the outcome of disease in bovine hosts and in combination with toxA to that in swine. The dermonecrotoxin encoding toxA, present in 12.5% of all strains, was detected in isolates from swine, small ruminants, cattle, and poultry. A significant association to the disease status, however, was only existent in swine, although with 66.7% we found a notably high prevalence of the toxin gene among strains from small ruminants. The genes toxA, tbpA and pfhA as well as capsule biosynthesis genes are supposed to be important epidemiological marker genes for characterizing P. multocida field strains. 相似文献
14.
Ramspott S Hartmann K Sauter-Louis C Weber K Wehner A 《Journal of Feline Medicine and Surgery》2012,14(4):262-266
Adrenal function may be altered in animals with hyperthyroidism. The aim of the study was to assess adrenal function of hyperthyroid cats (n = 17) compared to healthy cats (n = 18) and cats with chronic diseases (n = 18). Adrenal function was evaluated by adrenocorticotropic hormone (ACTH) stimulation test and the urinary cortisol to creatinine ratio (UCCR) was determined. Length and width of both adrenal glands were measured via ultrasound. Hyperthyroid cats had significantly higher cortisol levels before and after stimulation with ACTH than the other groups. However, the UCCR was not elevated in hyperthyroid cats. The size of the adrenal glands of hyperthyroid cats was not significantly different from the size of those of healthy cats. The results indicate that cats with hyperthyroidism have a higher cortisol secretory capacity in a hospital setting. The normal size of the adrenal glands suggests that cortisol levels may not be increased permanently. 相似文献
15.
Yutaka SUZUKI Sang‐Houn SONG Katsuyoshi SATO Kyoung‐Ha SO Astrid ARDIYANTI Shun KITAYAMA Yeon‐Hee HONG Sung‐Dae LEE Ki‐Choon CHOI Akihiko HAGINO Kazuo KATOH Sang‐gun ROH 《Animal Science Journal》2012,83(3):263-267
Accumulating data suggest a relationship between chemerin and energy metabolism. Our group previously described gene cloning, expression analysis and the regulatory mechanism of chemerin and its own receptor in mice and cattle. The objective of the present study was to investigate the physiological effect of chemerin on endocrine changes and energy metabolism in sheep using a biologically stable chemerin analog. The chemerin analog was intravenously administrated (100 or 500 µg/head) to sheep, and plasma insulin and metabolites (glucose, nonesterified fatty acids (NEFA), triglyceride, total cholesterol and high‐density lipoprotein (HDL) cholesterol) were analyzed. The chemerin analog dramatically increased the insulin levels, and glucose levels were decreased. NEFA levels were slightly decreased at 20 min but then increased gradually from 60 to 180 min after analog administration. In addition, injection of the chemerin analog immediately increased triglyceride and total cholesterol but not HDL levels. These results suggested that chemerin analog regulated insulin secretion related to glucose metabolism and the release of triglycerides in sheep in vivo. This study provides new information about endocrine and metabolic changes in response to chemerin in sheep. 相似文献
16.
Wehner A Hartmann K Hirschberger J 《Journal of the American Animal Hospital Association》2008,44(3):131-138
A human kit for cystatin C determination was evaluated for use with canine sera. A reference range was also established. The association between cystatin C and glomerular filtration rate (GFR) was evaluated in 60 dogs with various diseases, by using exogenous creatinine plasma clearance (ECPC) as a measure of GFR. The correlation between cystatin C and ECPC (correlation coefficient [r] = -0.630; P<0.001) was stronger than the correlation between serum creatinine and ECPC (r = -0.572; P<0.001). Nonrenal diseases (e.g., neoplasia, infection) did not influence serum cystatin C concentration. Test sensitivity was significantly better (P<0.001) for cystatin C (76%) than for creatinine (65%). Specificities for the two tests were 87% and 91%, respectively. 相似文献
17.
Marianne M Sloet van Oldruitenborgh-Oosterbaan Erica T W van den Broek Astrid J Spierenburg 《Journal of veterinary diagnostic investigation》2008,20(1):83-85
Blood lactate measurements are commonly used in exercising horses to determine the onset of lactate accumulation and in colic patients to assess clinical status and to indicate prognosis. To study the usability of a portable blood lactate meter based on dry chemistry (Lactate Pro), the data from this instrument were compared to data from a laboratory-used lactate meter based on wet chemistry (ABL 605 blood gas analyzer [ABL]). Heparinized blood samples were obtained from horses participating in a jumping experiment (n = 9), from horses cantering at maximal speed on a racetrack (n = 7), and from patients admitted to the Department of Equine Sciences at Utrecht University for severe colic (n = 13). Seventeen of these samples were tested in duplicate on both instruments to determine the repeatability of the measurements. Blood lactate concentrations measured with the Lactate Pro ranged from 0.8-17.6 mmol/liter and with the ABL from 1.0-18.6 mmol/liter. The correlation between lactate concentrations obtained using the Lactate Pro and values from the ABL was 0.90, and the relationship was represented by the following formula: y = 0.90 . x + 0.36, indicating a linear relationship between values produced by the ABL and Lactate Pro. The repeatability for the Lactate Pro was high (0.997), which is comparable to the ABL (0.999). 相似文献
18.
Hanna??wiek-Kupczyńska Thomas?Altmann Daniel?Arend Elizabeth?Arnaud Dijun?Chen Guillaume?Cornut Fabio?Fiorani Wojciech?Frohmberg Astrid?Junker Christian?Klukas Matthias?Lange Cezary?Mazurek Anahita?Nafissi Pascal?Neveu Jan?van?Oeveren Cyril?Pommier Hendrik?Poorter Philippe?Rocca-Serra Susanna-Assunta?Sansone Uwe?Scholz Marco?van?Schriek ümit?Seren Bj?rn?Usadel Stephan?Weise Paul?Kersey Pawe??KrajewskiEmail author 《Plant methods》2016,12(1):44
19.
Astrid ARDIYANTI Yoshie OKI Yoshihito SUDA Keiichi SUZUKI Koichi CHIKUNI Yoshiaki OBARA Kazuo KATOH 《Animal Science Journal》2009,80(1):62-69
To investigate the effects of bovine growth hormone (bGH) gene polymorphism on carcass traits and fatty acid compositions in Japanese Black cattle caused by nucleotide substitution of CTG (allele A)/GTG (allele B) at codon 127 and of ACG (allele A and B)/ATG (allele C) at codon 172 of bGH, GH genotypes of 135 cattle were determined using allele specific-multiplex polymerase chain reaction (PCR). Allele A gave greater rib thickness and lower melting point of fat (MP) while allele B gave higher C18:1% ( P < 0.05). Allele C gave higher C18:1, monounsaturated fatty acid (MUFA), unsaturated fatty acid (USFA) percentages ( P < 0.05). It also gave lower saturated fatty acid (SFA) percentages, higher MUFA/SFA and USFA/SFA ratios, and lower MP ( P < 0.05). Interactions of sex and GH alleles were analyzed. In heifers, allele A gave higher carcass weight, daily carcass gain, rib eye area, rib thickness, subcutaneous fat thickness, and BMS while allele B gave greater rib eye area and rib thickness ( P < 0.05). Allele C gave higher C18:1 ( P < 0.01), MUFA ( P < 0.01), USFA percentages ( P < 0.05) and MUFA/SFA and USFA/SFA ratios ( P < 0.01), and lower C16:0 and SFA percentages ( P < 0.05) and MP ( P < 0.01). GH gene polymorphism affected carcass traits and fatty acid compositions although the effects were more pronounced in heifers. 相似文献
20.
Ludewig E Gensler A Oechtering G Gosch D 《Berliner und Münchener tier?rztliche Wochenschrift》2010,123(11-12):506-515
Radiation exposure of body parts of persons, needed to restrain small animal during the examination, varies depending on the distance and position in relation to the patient, the region investigated, and the exposure settings applied. The aim of the study was to quantify the effects of these factors on the ambient dose. The dosimeter was positioned with varying distance from the direct beam (from 30 to 150 cm) and on different level above the floor (55 cm, 85 cm, and 150 cm. The study consisted of two parts. In the first part a plastic water tank (thickness: 18 cm) was used as source of scatter radiation. Different exposure settings (77 kVp; 20 - 10 - 5 - 2.5 - 1.25 mAs) were applied. In the second part dose was measured during the examination of the abdomen of a large dog (thickness: 18 cm; 77 kVp, 20 mAs) and of the skull of a cat (thickness: 6 cm; 55 kVp, 20 mAs). At the level of the patient (85 cm above the floor) the dose decline relative to the distance followed a quadratic function. In the series "abdomen-dog" the mean dose values ranged from 51.6 microSv (30 cm distance) to 1.02 microSv (150 cm distance). The corresponding doses for the series "skull-cat" were 0.98 microSv and 0.02 microSv, respectively. Comparably lower doses were measured on the lines along the table, when non-irradiated parts of the body were located between the exposed patient volume and the dosimeter. At 150 cm above the floor higher doses were observed relative to the doses at the level of the table. The following conclusions can be drawn: (1.) Depending on the target volume the ambient dose varies in a wide range. (2.) An increase of the distance of only few centimetres is reducing exposure considerably. Therefore persons should make use of it whenever this is possible. (3.) Persons should stand on the short sides of the table while fixing the patient. (4.) Head and neck are relatively highly exposed. Methods to protect the thyroid gland and the eye lens are indicated. (5.) Since different exposure levels can be applied in digital radiography, the range of dose levels is rather wide. Therefore strict dose discipline (e.g. by use of exposure tables and dose indicators) is necessary to avoid continuing overexposure. 相似文献