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991.
The growth performance and endocrine responses of male weaner pigs (3 to 8 weeks of age) was evaluated in two different environments (clean and dirty) and housing (single or groups of 10 pigs/pen) conditions. The dirty environment contained significantly elevated ammonia, carbon dioxide and dust levels compared with the clean environment. Pigs grew faster and consumed more feed in the clean environment and this was associated with reduced plasma cortisol concentrations compared with pigs in the dirty environment. Pigs housed in groups in the dirty environment had increased β-endorphin and decreased IGF-I concentrations compared to group housed pigs in the clean environment. Feed conversion efficiency did not differ due to environment or group housing. Plasma concentration of cortisol, β-endorphin, IGF-I and IGF-II did not differ between single and group housed pigs. Activity of the hypothalamic-pituitary-adrenal (HPA) axis was greater in response to environmental conditions than group housing, and this was associated with reduced growth in weaner pigs. 相似文献
992.
The effect of true milk use in the diet of Spanish Brown Swiss male calves on animal performance, carcass and meat quality, and fatty acids composition was studied. In experiment 1, the effect of milk intake [ad libitum continuous (ADLIB) feed vs. restricted 0.7 during 75 days followed by ad libitum feed (RESTR)] and slaughter endpoint (225 kg vs. 5 month) were studied. In experiment 2, ad libitum concentrate feeding [grain-fed (GF)] was compared with milk supplementation until slaughter [milk-fed (MF)] in calves slaughtered at 345 kg. As regards to milk intake, carcass weight and degree of fatness were higher in the ADLIB group (P<0.05). The RESTR group revealed a higher percentage of saturated fatty acids (P<0.05). In experiment 2, the MF group exhibited a higher fat percentage (P<0.05), lower press and cooking losses (P<0.05), and higher scores for tenderness and juiciness (P<0.05) than the GF group. The percentage of saturated fatty acids was higher in the MF group (P<0.05). The results suggest that true milk use in veal production could be an advantageous alternative in terms on production costs, animal performance, and carcass and meat quality. 相似文献
993.
Deborah C Mandell Elaine Holt 《Veterinary Clinics of North America: Small Animal Practice》2005,35(2):455-80, vii-viii
Ophthalmic emergencies are common presenting complaints in an emergency room. Most ophthalmic emergencies can be treated and stabilized until an ophthalmologist can be consulted. Most ocular emergencies involve loss of vision, compromised globe integrity, or severe ocular pain. Delay in treating true emergencies may result ina blind eye or loss of an eye. This article discusses the clinical signs,diagnosis, and treatment as well as the prognosis of some of the more common ophthalmic emergencies. 相似文献
994.
K Deichsel H-O Hoppen RM Bruckmaier G Kolm C Aurich 《Reproduction in domestic animals》2005,40(2):117-122
Lactation in the mare is associated with changes in the release of metabolic as well as reproductive hormones. Plasma glucose concentration is constantly reduced in lactating compared with non-lactating mares. Several metabolic signals have been proposed to link nutrition and somatic metabolism with reproductive function. The following experiment was performed to study the effect of acute hypoglycaemia on the release of insulin-like growth factor-1 (IGF-1) and luteinizing hormone (LH) in cyclic mares. Different doses of insulin (0.1 and 0.2 IU/kg body weight) were given to induce a decrease in plasma glucose concentration, as existent in lactating mares. All horses treated with insulin developed a hypoglycaemia over a time period of nearly 10 h. The IGF-1 and LH were analysed before and after insulin administration. At no point of time, a significant difference between the two insulin treatments and the control treatment was observed. Therefore, the hypoglycaemic horse is apparently able to provide the brain with sufficient glucose. Short-term hypoglycaemia does not affect the hypothalamo-pituitary-ovarian axis, and concentrations of IGF-1 and LH remained stable during insulin-induced hypoglycaemia. An acute change in plasma glucose concentration is thus not or at least not the only metabolic signal that links nutrition and somatic metabolism with reproductive function in the horse mare. 相似文献
995.
H. Neubauer L. D. Sprague R. Zacharia H. Tomaso S. Al Dahouk R. Wernery U. Wernery H. C. Scholz 《Zoonoses and public health》2005,52(5):201-205
Burkholderia mallei causes glanders or farcy in solipeds, a disease that must be reported to the OIE (Office International des Epizooties, Paris, France). The number of reported outbreaks has increased steadily during the last decade. Serodiagnosis is hampered by the considerable number of false‐positives and ‐negatives of the internationally prescribed tests. The major problem leading to low sensitivity and specificity of complement fixation test (CFT) and enzyme‐linked immunosorbent assay (ELISA) has been linked to the test antigens currently used, i.e. crude preparations of whole cells. Future perspectives for the development and evaluation of serological test kits using well‐characterized single antigens are discussed in the light of recent molecular research on B. mallei and the closely related saprozoonotic agent B. pseudomallei. 相似文献
996.
The interactive effects of rooting volume and nutrient availability in a skeletal soil medium designed to meet street tree and pavement needs were observed in a containerized experiment. Benjamin fig (Ficus benjamina L.) was grown in a stone-soil blended skeletal soil material (CU-Soil™) and compared to a loam soil. The same topsoil used as the soil component in the skeletal soil material was used as the sole component in the comparison soil-only treatment.Plants grown in the skeletal soil material had reduced leaf tissue N content and depressed growth compared with plants grown in non-diluted soil. No other mineral deficiencies were found. Leaf number, chlorophyll concentration, shoot weight, and root characteristics were all affected.Reduced growth from soil dilution could be offset by the provision of an enlarged rooting volume for root development. Large containers of skeletal soil were observed to have smaller root systems compared to equivalent net volumes of loam soil at the first two harvest dates of the study. By the end of the study, the large containers of skeletal soil were observed to have developed larger root systems compared to equivalent net volumes of loam soil; resulting in comparable leaf N levels and total plant dry matter. Plants in skeletal soil had lower shoot: root ratios at the end of the study. Investing resources to further root growth in times of nutrient shortages is a probable plant reaction as evidenced by differences in specific root length between treatments. The study allowed a method for directly partitioning the containerization effect by having equivalent amounts of soil over two volumes. 相似文献
997.
998.
Existing spatial patterns of a forest are in part a product of its disturbance history. Using laser altimetry and field measures
of canopy top height to represent pre- and post-hurricane canopy topography, respectively, we measured changes in spatial
patterns of stand structure of a United States southern mixed coniferous-deciduous for est. Autocorrelative and fractal properties
were measured in this opportunistic study to quantify changes in canopy architecture along twelve, 190-250 m transects that
were subjected to moderate to high levels of wind disturbance. Prior to the hurricane, canopy heights were autocorrelated
at scales <40 m with an average fractal dimension of 1.71. After the disturbance, autocorrelation disappeared; the average
fractal dimension rose to 1.94. This shift towards spatial randomness illustrates part of the cyclical nature of ecosystem
development. It shows how a catastrophic collapse of biomass accumulation corresponds to a decrease in ecosystem organization
across a landscape.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
999.
Tsutomu MATSUMOTO Yuichiro NARA Hiromitsu FURUYA Harumi TAKAHASHI Kiichi TAIRAKO Hideki YAMAMOTO 《Journal of General Plant Pathology》2002,68(4):382-384
L11A-Fukushima (L11A-F) derived from attenuated isolate LuA of Tomato mosaic virus (ToMV) has the highest ability to cross protect against virulent ToMV among LuA and its derivatives and is stably inherited.
Growth, yield, fruit quality and symptom attenuation of inoculated tomato plants did not differ significantly between L11A-F and L11A. The infectivity of progeny viruses in tomato infected with LuA-F was less than 4% of that with virulent ToMV. From these
results, L11A-F appears to possess the properties necessary for practical use. To manage L11A-F strictly, a PCR-based assay to detect trace contamination of virulent ToMV in L11A-F preparations was established.
Received 10 June 2002/ Accepted in revised form 30 October 2002 相似文献
1000.
Shohei MATSUURA Shigeru HOSHINO Hideaki HAYASHI Tetsuyuki KOHGUCHI Kyoji HAGIWARA Toshihiro OMURA 《Journal of General Plant Pathology》2002,68(1):99-102
DAS-ELISA proved to be reliable enough to detect a latent infection by Tomato spotted wilt virus (TSWV) in asymptomatic stock plants of chrysanthemum. A high density of Frankliniella occidentalis, the predominant vector, in the presence of latently infected stock plants resulted in a high incidence of disease in the chrysanthemum
production field. The incidence of disease was low when the vector thrips were not abundant in spite of the presence of latently
infected stock plants. These results suggest that an infestation of the vector thrips causes severe secondary spread of TSWV
originating from latently infected stock plants in chrysanthemum production fields.
Received 27 July 2001/ Accepted in revised form 27 November 2001 相似文献