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31.
AIM: Using specified indices, to determine the nutritional and thermal status of calves between 1 and 4 days of age.

METHODS: After birth, calves (n=106) were collected daily, according to farm practice. Over the following 4 days a jugular blood sample and rectal temperature were taken twice daily before feeding. Plasma concentrations of glucose, beta-hydroxybutyrate and urea, and gamma-glutamyl transferase (GGT) activities were determined. The significance of differences in plasma composition and rectal temperature between calves whose birth had been assisted or unassisted, and between calves with low and high plasma GGT activities 24 h after birth, was determined using repeated measures analysis of varianc

RESULTS: There were no marked differences in plasma metabolite levels or body temperature of assisted and unassisted calves. Calves that had high plasma GGT activities 24 h after birth had higher plasma glucose concentrations over the 4 days than calves that had low plasma GGT activities (p<0.001). Overall, compared to published data on poorly-fed and hypothermic calves, calves in this study were normoglycaemic, their plasma beta-hydroxybutyrate and urea concentrations were low and their rectal temperatures were normal, indicating that they were well fed and did not become hypothermic.

CONCLUSIONS: The nutritional and thermal status of at least 90% of the calves was compatible with good health and survival during the first 4 days after birth.  相似文献   
32.
1. In 1993 the EU Life Programme granted funds to establish a demonstration project on river and catchment restoration. The aim is to improve understanding of ecosystem diversity, the impact on biodiversity of human activities, and the restoration of natural functions and biodiversity. The total cost of the project will be approximately £5 m up to the beginning of 1997. 2. The demonstration project covers three different types of rivers and geology in the UK and Denmark. The three damaged rivers and their floodplains have been restored on stretches of several kilometres. 3. A comprehensive monitoring programme has been set up to examine the physical, chemical and biological effects of restoration for integrated catchment management, nature conservation, water quality, river hydrology, flood prevention and amenity. 4. The project will also produce reports, videos, a river restoration handbook and other material on the development, implementation and results of the project. An EU network of contacts with organizations, river managers and others with interests in river restoration will be established.  相似文献   
33.
AIM: To use the electroencephalogram (EEG) to ascertain whether the response of the cerebral cortex to the noxious stimulus of castration varied with age in lambs.

METHODS: Two groups of East Friesian lambs were selected according to age; the mean age of the younger group (n=21) was 12 (SD 2) days and the older group (n=20) was 29 (SD 1) days. Anaesthesia was induced via mask using 4% halothane in oxygen, and maintained using 1.5% halothane in oxygen at a flow rate of 4 L/min. Once a stable plane of anaesthesia had been achieved, data collection of EEG and electrocardiographic (ECG) readings commenced, and the lambs were castrated 15 min later, using rubber rings. Median and 95% spectral edge frequencies (F95) and total EEG power (ptot) were derived from data from the EEG.

RESULTS: Following castration, there was an increase in the median frequency (F50) in the younger lambs (p=0.002), and an increase in ptot in both groups (p=0.05), which was of greater magnitude in the older lambs. There were no significant changes in the F95. Both younger and older lambs exhibited a transient bradycardia (p=0.001 and p=0.01, respectively).

CONCLUSIONS: These differences in the cortical response between the two groups suggest that 2-week-old lambs undergo a qualitatively different perception of the noxious stimulus of castration compared to 4-week-old lambs.  相似文献   
34.
35.
Isolated diatomic molecules of iodine monochloride (ICl) were photodissociated by a beam of linearly polarized light, and the resulting ground-state Cl atom photofragments were detected by a method that is sensitive to the handedness (helicity) of the electronic angular momentum. It was found that this helicity oscillates between "topspin" and "backspin" as a function of the wavelength of the dissociating light. The helicity originates solely from the (de Broglie) matter-wave interference of multiple dissociating pathways of the electronic excited states of ICl. These measurements can be related to the identity and to the detailed shapes of the dissociating pathways, thus demonstrating that it is possible to probe repulsive states by spectroscopic means.  相似文献   
36.
Apparent restihg energy expenditure (AREE) and respiratory quotient (RQ) were determined by open flow indirect calorimetry in a group of 104 apparently resting, critically ill, postoperative and severely traumatized dogs. The evaluations were conducted in a calm, temperature-controlled environment after at least a 12-hour fast. Subjects were allowed to acclimilate to the monitoring equipment prior to beginning the study. The clinical patients were compared to a group of 20 clinically normal, apparently resting, client owned dogs (NC). The data was also compared to published normals (NP) for energy expenditure of apparently resting dogs. Measurements were indexed to actual body weight in kilograms (BW) as well as to metabolic body size(BW0.75). Measurements of VO2 (VO2/kg and VO2/kg0.75) and VCO2 (VCO2/kg and VCO2/kg0.75) were used to calculate the RQ and the AREE. Critically ill, postperative and severely lower RQ values AREE/kg or AREE/kg0.75 (p=0.39). The PO&T dogs did exhibit significantly lower RQ values (p<0.0001) than either the (NC) or (NP) groups. Measured AREE of the PO&T dogs was significantly less than a calcualted value using the illness/injury/infection energy requirement (IER), (p<0.0001). Energy expenditure in typical trauma and postoperative patients may commonly be overstimated by the IER method. Conclusion: The AREE of critically ill, postoperative and severly trumatized dogs was not higher than healthy dogs as has been previously suggested in the literature.  相似文献   
37.
The aim of this study was to describe the scintigraphic appearance and location of the sacroiliac joint (SI-joint) in dorsal and dorso 30 degree lateral views of the equine pelvis in a scintigram. The pelvis from 10 different horses was prepared by attaching plastic tubes along relevant margins of the bone and around the SI-joint. A radioactive solution was injected into the tubes, and scintigraphic images were acquired with a gamma camera. Five specific landmarks were identified on the left and right sides of the pelvis. There was no significant difference in the distance measurements between the left and right sides in the dorsal view. The SI-joint was roughly ovoid in shape, with its long axis angled to the midline. The most craniolateral point of the SI-joint (Y) was located at the middle (SD = 0.04) of a line drawn from the caudal margin of the tuber sacrale (TS) to the craniolateral margin of the tuber coxa (TC), which was called TS-TC. In 85% of the specimens, the long axis of the SI-joint (SILA) was located caudal to or intersecting TS-TC, and the mean angle between SILA and TS-TC was 16.4 degrees (SD = 5.6 degrees). The distance from the caudomedial point of the SI-joint (Z) to Y was 0.38 times (SD = 0.04) the length of TS-TC. The distance from the tuber sacrale to the medial border of the SI-joint (TS-X) was 0.15 times (SD = 0.02) the length of TS-TC. In the oblique view, the SI-joint appeared wider and was positioned more laterally compared to the dorsal view. The distance TS-Y increased to 0.61 times (SD = 0.046) TS-TC, but SILA/TS-TC was essentially unchanged. The mean angle between TS-TC and SILA increased to 20.9 degrees (SD = 5.6 degrees). TS-X increased to 0.31 times (SD = 0.037) TS-TC. The location of the SI-joint was very similar in all horses, which makes it possible to estimate the location of the SI-joint in a scintigram in which the tuber sacrale and the craniolateral margin of the tuber coxa are identified.  相似文献   
38.
Objective To measure the plasma cortisol response in lambs castrated and docked by three different methods (ring castration and tail docking, ring and clamp castration and tail docking; ring and clamp castration and ring tail docking) for 4 h after treatment.
Design A physiological study with controls.
Procedure A rubber ring was applied to the scrotum. Then the castration clamp was placed, distal to the ring, on each spermatic cord such that there was no overlap of the crush lines.
Results There were no differences in the cortisol secretion of the lambs castrated and tail docked by the ring only and by the ring plus castration clamp methods. Using the castration clamp in addition to the ring on the tail had no effect on cortisol secretion.
Conclusions Using the castration clamp did not appear to reduce the cortisol response to ring castration and docking, as demonstrated elsewhere, because the areas of uncrushed tissue between the two castration clamp crush lines allowed nociception from ischemic scrotal tissue to be transmitted cranially via undamaged nerve fibers.  相似文献   
39.
A controlled period of submaximal exercise on a treadmill was used as a standardised stress test in 6 young horses to monitor the effects of training. Circulating plasma concentrations of immunoreactive beta-endorphin (IR beta-EP) were measured before, during and after the exercise period. The stress test was conducted on 3 occasions during an intensive training program lasting 14 weeks. In week 3 a marked increase in plasma IR beta-EP (P = 0.003) was demonstrated as a result of training, but by the last exercise test performed in week 9 no significant increase in plasma IR beta-EP concentrations could be detected. During the training period the basal concentrations of plasma IR beta-EP significantly decreased (P = 0.0059). Plasma adrenocorticotrophin (ACTH) did not increase during exercise, although there was a trend of decreasing basal plasma ACTH by the end of the training period. It was concluded that a standardised work test acted as a mild stress to unfit horses, but as the horses' fitness increased the hormonal response to exercise diminished. Basal plasma beta-EP concentrations were decreased with increasing fitness.  相似文献   
40.
The Rdm4 gene from soybean cv. Hutcheson has been extensively used to incorporate resistance to soybean stem canker (SSC), caused by Diaporthe phaseolorum var . meridionalis (Dpm), into soybean commercial cultivars. The objective of this work was to characterize the inheritance of the Rdm4 locus in different populations derived from the cross: J77-339 ( rdm / rdm , susceptible) × Hutcheson ( Rdm4 / Rdm4 , resistant) in independent interactions with two local isolates of Dpm. Four F2 populations were obtained and two were advanced to the F3 generation as separate F2:3 families to perform progeny tests. Each population was inoculated with the CE109 and/or CE112 isolates of Dpm. Within each plant–pathogen interaction, the resistance gene segregated as completely dominant. However, cross resistance, or opposite disease reactions, to CE109 and CE112 isolates of Dpm were observed in four F2:3 families, indicating an intergenic recombination event between two nonallelic genes interacting specifically with each isolate of Dpm. The distance between them, estimated as the recombination fraction, was 29%, suggesting that both genes were not tightly linked, but close enough to segregate together in most crosses. Results indicated the existence of a genomic region in cv. Hutcheson composed of race-specific resistance loci with at least two Rdm genes: the previously recognized Rdm4 and a novel gene, tentatively named Rdm5 , conferring specific resistance to Dpm isolates CE109 and CE112.  相似文献   
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