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Objective To measure plasma cortisol responses in calves dehorned using a scoop after administration of local anaesthesia and/or cautery of the wounds.
Design A physiological study with controls.
Procedure There were six treatments: control handling with and without local anaesthesia, dehorning, dehorning after local anaesthesia, dehorning followed by wound cautery, and dehorning after local anaesthesia followed by wound cautery. Blood samples were taken before and after dehorning.
Results Dehorning caused an increase in plasma cortisol concentrations, which decreased a little to plateau values and then declined to pretreatment values 3 to 4 h after dehorning. The peak was smaller after local anaesthesia was administered but when its effects wore off, cortisol concentrations increased and thereafter were similar to those in the dehorned animals. The combination of local anaesthesia and cautery resulted in a plasma cortisol response similar to those in control calves with or without local anaesthesia.
Conclusions If plasma cortisol concentrations reflect the distress being experienced by the calves, then local anaesthesia reduces the acute distress for about 3 h after dehorning but not during the subsequent 3 to 4 h. Combining local anaesthetic and cautery prevented the significant increase in plasma cortisol following dehorning and may eliminate the acute distress caused by scoop dehorning.  相似文献   
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Objective —This study evaluates skin bacterial flora before and after aseptic preparation of clipped and nonclipped arthrocentesis sites in horses. Study Design —The hair over one midcarpal joint and one distal interphalangeal joint on each horse was clipped. The contralateral joint served as the nonclipped comparison. Animals or Sample Population —Twelve adult horses. Methods —A prescrub sample for microbial culture was taken from the dorsal surface of all four joints for each horse. Each site was aseptically prepared with povidone iodine and 70% alcohol, followed by postscrub sampling for microbial culture. Colony forming units (CFUs) were determined for each sample, 24 hours after inoculation of blood agar plates. Results —There was no significant difference (P >.05) in number of postscrub CFUs between clipped and nonclipped skin over the midcarpal or distal interphalangeal joints. Percent bacterial reduction (mean ± SD%) after aseptic preparation differed significantly (P=.02) between clipped (99.8 ±.003%) and nonclipped (96.2 ±.05%) skin at the midcarpal joint, but not at the distal interphalangeal joint (clipped, 98.5 ±.03% and nonclipped, 97.8 ± 0.21%). There was a significant difference (P=.009) in number of prescrub CFUs obtained from clipped and nonclipped skin for the midcarpal joint. There was no significant difference in number of prescrub CFUs between clipped and nonclipped skin at the distal interphalangeal joint. Bacteria isolated from both clipped and nonclipped skin sampled postscrub included Bacillus sp, nonhemolytic Staphylococcus sp, and Micrococcus sp. Conclusions —The presence of hair over the midcarpal and distal interphalangeal joints does not appear to inhibit the ability of antiseptics to effectively reduce bacterial flora to an acceptable level for arthrocentesis. Clinical Relevance —Aseptic preparation of the skin over the midcarpal and distal interphalangeal joints can be accomplished without hair removal in horses.  相似文献   
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Abstract. Lipid class and fatty acid analyses were carried out on eight batches of pre-fertilized eggs of Atlantic halibut, Hippoglossus hippoglossus (L.). These batches were classified as ‘viable’ or ‘non-viable’ according to fertilization rate, blastomere symmetry and incubation success. The lipid class and fatty acid compositions were very similar between egg categories with exception of cholesterol which was shown to be significantly greater in the ‘non-viable’ eggs. Polar lipid classes predominated (67·1% and 67·0% of the total lipid for ‘viable’ and ‘non-viable’ egg batches respectively), with phosphatidylcholine (PC) being the major class (43·2% and 43·5%) and triacylglycerol (TAG) the main neutral lipid class (18·8% and 17·8%). Gas liquid chromatography of fatty acid methyl esters from the total lipid revealed no significant differences in fatty acid composition. The fatty acid profiles of viable egg batches showed five major fatty acids 16:0 (17·3%), 18:0 (4·8%), 18:1n-9 (9%), 20:5n-3 (119%) and 22:6n-3 (25·9%). The results are discussed in terms of the potential role of lipids as egg quality determinants in fish.  相似文献   
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ABSTRACT Despite the fact that nonemployment income makes up approximately one-third of all personal income, its impact on local area economies has not been closely examined. This study uses Michigan county data to examine the impact of nonemployment income on nonbasic income over a twenty-seven-year period. This impact is compared to the impact of basic income by employing regression analysis to estimate comparative multiplier effects for both types of income. Nonemployment income is found to have a significant impact on nonbasic income, particularly in metropolitan and nonmetropolitan urban counties, where its impact appears to be stronger than that of basic income.  相似文献   
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ABSTRACT Portes and Borocz's (1989 ) segmented assimilation framework argued that the assimilation of immigrants into American society does not necessarily or automatically lead to similarity and equality with the mainstream culture. Instead, endowed human capital, the nature of immigration, and reception contextualize the process and potentially lead to differential outcomes. Recognizing that spatial differences in assimilation may also exist, the segmented assimilation framework is extended within this paper to include a more explicit recognition of geography's role in shaping the assimilation trajectory. The empirical analysis draws upon the 1980 and 1990 PUMS data files, and compares the assimilation trajectory of Chinese immigrants (excluding Hong Kong and Taiwanese origins) across the New York, San Francisco, and Los Angeles metropolitan areas. Based upon period of arrival and age in 1980 and 1990, measures of assimilation are compared across these three metropolitan areas, along with the role of internal migration in maintaining or decreasing assimilation differences. The analysis indicates that the progress of assimilation varies significantly over space, with spatial differences in measures of assimilation persisting over time, despite the role of internal migration. Reasons as to why this occurs are presented in the conclusion.  相似文献   
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A new system for soil studies   总被引:1,自引:0,他引:1  
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Nine horses were premediated with acepromazine, and anesthesia was induced with guaifenesin and thiamylal. Anesthesia was maintained in four horses with halothane in oxygen, and in five horses with halothane in oxygen plus a constant dose infusion of detomidine. Both maintenance regimens produced a MAC equivalent of 1.4 at the ambient barometric pressure. Hemodynamic and respiratory measurements were made after the horses were anesthetized, during surgical manipulations involving skin or tissues other than nerves, during manipulation and transection of digital nerves, and after surgery while the limbs were being bandaged. Heart rate was significantly higher in horses anesthetized with halothane only than in horses that also received detomidine; there were no other differences in hemodynamic function or recovery characteristics. Respiratory rate was significantly higher than baseline during soft tissue and nerve manipulations; arterial blood pressure was significantly higher after surgery began and highest during neurectomy; cardiac output and cardiac index were significantly decreased during surgery; systemic vascular resistance was significantly increased during neurectomy and bandaging and highest during neurectomy. The data suggest that the increase in blood pressure often associated with surgical stimulation is caused by increased vascular resistance and may be accompanied by a decrease in cardiac output.  相似文献   
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