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71.
Summary Three methods that have been suggested as inexpensive for characterisation of gum arabic were evaluated in characterising
and monitoring gum arabic of commerce. The methods were; physico-chemical and carbohydrate analysis (analytical), determination
of molecular mass by gel permeation chromatography (gpc) and an Enzyme Linked Immunosorbent Assay (ELISA). The results revealed
that gpc provides quick and consistent information on gum arabic of commerce from Acacia senegal. It was able to detect the three chemical species; Arabinogalactan protein complex (AGP), Arabinogalactan (AG) and Glycoprotein
(GP) fractions that are typical of A. senegal and could differentiate gum from the two varieties of A. senegal, i.e., var. senegal and var. kerensis on the basis of the enhanced UV peaks in the later. It was able to distinguish gums
from different Acacia species as well as suspected contaminants. The analytical method could differentiate between the two varieties of A. senegal on the basis of optical rotation, protein content and viscosity which were noted as basic parameters for comparison. However,
where the proposed FAO (1990) specifiction was applied in its present form, it failed to adequately characterise gum from
var. kerensis as gum arabic. Secondly, natural product variability i.e., the observed between sample variation made the method to have
limited application in adequately characterising gum arabic from even a single source. The method was able to distinguish
gums from the other Acacia species purely on the basis of optical rotation though information on nitrogen and sugar composition was also invaluable. Generating
data on the composition of sugars requires time that militates against the method as a slow process. Because of the overlap
in the analytical parameters for some samples, it could be adequately characterise two of the samples that were presented
as suspected contaminants. Nonetheless, by combining information of gpc and analytical data, a better evaluation of the gums
was achieved. The method of Elisa has a future scope but will require refining it by utilising monoclonal antibodies to be
developed for it to be more specifc in characterising gum arabic from A. senegal.
The authors wish to thank Dr. P. A. Williams of the North East Wales Institute, Deeside, Clwyd, UK for the use of the gpc
and Elisa facilities. B.N.C. is grateful to the Kenyan and British governments for financial support. 相似文献
72.
I Ruiz‐González MA Sánchez RA García‐Fernández P García‐Palencia B Sánchez CA Letelier A González‐Bulnes JM Flores 《Reproduction in domestic animals》2012,47(2):274-280
The objective of this study was to investigate differences on the endometrial immunoexpression of type I IFN receptor subunit 1 (IFNAR1) and oxytocin receptor (OTR) during the time of maternal recognition of pregnancy in sheep, when oestrus is synchronized with either prostaglandin analogues (group PG) or conventional progestagens (group P). Plasma progesterone was measured from day 0 to 21 post‐coitus (pc) (day 0 = day of oestrus). Immunohistochemistry was performed in samples of uterine horns from pregnant sheep on days 9pc, 13pc, 15pc, 17pc and 21pc to locate IFNAR1 and OTR expression in different endometrial compartments. Mean levels of plasma progesterone were different between treatments, obtaining higher levels in the PG group than in the P group (p < 0.05). Comparing days of pregnancy, IFNAR1 protein expression was different in the luminal epithelium (LE) (p < 0.05), while OTR was different in the LE and in the superficial glandular epithelium (SG) (p < 0.05). Temporal variation on the expression of both proteins from day 9pc to 21pc has been evidenced. IFNAR1 and OTR expression did not show significant differences between treatments. However, the response observed in the endometrium was highly inconsistent when prostaglandin analogues were used. Therefore, the protocol based on prostaglandin analogues still needs to be optimized before being considered as a better alternative to progestagens for oestrous synchronization in sheep. 相似文献
73.
FRM Soto WG Viana GCB Mucciolo FYM Hosomi CI Vannucchi CP Mazzei AR Eyherabide C De Fátima Lúcio RA Dias SS De Azevedo 《Reproduction in domestic animals》2009,44(6):927-931
The aim of this research was to evaluate the efficacy of zinc gluconate associated with dimethyl sulphoxide (DMSO) for chemical neutering in canine males. Fifteen sexually mature male dogs were divided in two groups, named control and treated. An injection was administered to both testicles, at a concentration of 26.2 mg zinc gluconate per ml and 0.5% DMSO in the treated group (11 dogs). The control group was given injections of saline solution (four dogs). Clinical examination and blood collection for a haemogram were done both before and after drug injection. There were 12 spermograms performed to analyse sperm motility, sperm vigour, ejaculate volume, testicle size, pathology and sperm concentrations. Libido was also measured. An ultrasound examination and histopathology were performed at the end of the experiment. Dogs’ libido after chemical injection was reduced by over 50%. The spermogram analysis showed final mean results of 14.54% for sperm motility, 0.72 of sperm vigour and 37 150 per million spermatozoa per millilitre, values considered below the necessary levels at which fertilization can occur. Ultrasound and histopathology analyses of testicles for the treated group revealed more intense injuries when compared with the control group, with compromised testicular parenchyma and a decrease of germ cell number leading to total atrophy, indicating that the treatment reduced the fertilizing potential of male dogs, promoting a possible subfertile status. 相似文献
74.
R DeRossi AB Verde-Selva RA Bertoni RHS Ruzzon AB Silva-Neto 《Australian veterinary journal》2010,88(9):362-367
Objective To determine the anaesthetic and systemic effects of dorsolumbar epidural anaesthesia using non-stylet multiport catheters via the caudal approach to administer hypertonic 5% lignocaine (HL) or hypertonic 0.5% bupivacaine (HB) to the flank in standing cattle. Materials and methods Six healthy adult cattle weighing 310–455 kg received 0.2 mg/kg HL or 0.025 mg/kg of HB; control animals received 0.9% saline solution. All drugs were injected into the dorsolumbar epidural space via a caudal approach through a non-stylet multiport catheter. Each animal received each treatment at random. Evaluations of anaesthesia, ataxia, heart rate, arterial pressures, respiratory rate and rectal temperature were obtained at 0 (basal), 5, 10, 15, 30, 45, 60, 75, and 90 min after epidural injection and then at 30-min intervals until loss of anaesthesia. All animals received a standard noxious stimulus and a 4-point scale was used to score the response. A second scale was used to score ataxia. Results The duration of anaesthesia in the upper and lower flanks in cattle was 68 ± 12 and 110 ± 15 min (mean ± SD) after dorsolumbar epidural HL or HB, respectively. Both hypertonic local anaesthetics produced a mild ataxia. The systemic changes were within acceptable limits in these clinically healthy cattle. Conclusion In standing cattle the dorsolumbar epidural injection of hypertonic lignocaine provided faster onset of anaesthesia and fewer cardiovascular effects, but had a shorter duration of anaesthesia than hypertonic bupivacaine. 相似文献
75.
76.
77.
78.
The optimal method of control of caseous lymphadenitis of sheep caused by Corynebacterium pseudotuberculosis is eradication of infection by identification and removal of infected carrier animals. Current serological approaches to identification of infected sheep are generally hampered by low sensitivity and specificity of available tests. The objective of this study was to develop a whole blood assay for detection of C. pseudotuberculosis-infected sheep, based on detection of IFN-gamma response to whole cell C. pseudotuberculosis antigens, and to determine the reliability of the assay. A commercially available bovine interferon-gamma assay enzyme-linked immunosorbent assay was used and the test optimised using experimentally infected sheep. The assay was also tested on known CLA-negative sheep. Setting a IFN-gamma optical density cut-off at 0.100 as positive under the conditions used, the test detected C. pseudotuberculosis experimentally infected sheep over a 450-day period with a reliability of 95.7%. It identified known non-infected sheep with a reliability of 95.5%. Repeated vaccination of three uninfected sheep with a commercially available bacterin-toxoid vaccine did not interfere with the assay. The IFN-gamma response of sheep whole blood to C. pseudotuberculosis antigens offers promise for use in a test-and-removal approach to eradication of CLA in sheep. 相似文献
79.
SP SYLVESTER KJ STAFFORD DJ MELLOR RA BRUCE RN WARD 《Australian veterinary journal》1998,76(2):123-126
Objective To measure the plasma cortisol response in calves dehorned by four different methods (scoop, guillotine shears, saw, embryotomy wire) for 9 h after dehorning.
Design A physiological study with controls.
Procedure Horn amputation was carried out on calves restrained manually in a race.
Results The four methods of dehorning provoked similarly increased cortisol responses which lasted for 6 h. During the first hour after dehorning the plasma cortisol concentrations were similar to those following ACTH injection. The overall cortisol response to control handling was about 30% of the responses to dehorning.
Conclusions The similarity of the cortisol responses produced by the four methods of dehorning suggests that the distress experienced by calves following dehorning by amputation is similar regardless of method used. 相似文献
Design A physiological study with controls.
Procedure Horn amputation was carried out on calves restrained manually in a race.
Results The four methods of dehorning provoked similarly increased cortisol responses which lasted for 6 h. During the first hour after dehorning the plasma cortisol concentrations were similar to those following ACTH injection. The overall cortisol response to control handling was about 30% of the responses to dehorning.
Conclusions The similarity of the cortisol responses produced by the four methods of dehorning suggests that the distress experienced by calves following dehorning by amputation is similar regardless of method used. 相似文献
80.
Implementation and use of a microcomputer-based management information system to monitor dairy herd performance 总被引:1,自引:1,他引:0
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Lissemore KD Leslie KE Menzies PI Martin SW Meek AH Etherington WG 《The Canadian veterinary journal. La revue veterinaire canadienne》1992,33(2):114-119
A microcomputer-based herd management information system was implemented as part of the herd health program provided to 13 dairy clients by the Ontario Veterinary College, University of Guelph. The study was conducted over a two year period. Data were collected from on-farm event diaries, veterinary visit reports, and production testing information. Selected indices of reproduction, udder health, production, and heifer performance were reported. It was concluded that the implementation of a microcomputer-based information management system, operated as a bureau service, was feasible. However, limitations to the implementation in veterinary practice were identified. 相似文献