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11.
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   
12.
13.
Cohort studies were conducted on 29 pigs from 3 villages in the Highlands of Papua New Guinea. Animals ranged in age from 9 d to 5 m old. Three hundred and twenty nine faecal samples were collected from individual pigs followed over 3 to 6 w periods, and were examined for group A rotavirus antigen by ELISA, and rotaviral genomic RNA by polyacrylamide gel electrophoresis (PAGE). Electron microscopy was also conducted on selected samples. Group A rotavirus was detected in the faeces of 16 pigs with infected individuals coming from all villages. Non-group A rotavirus resembling group C was found in faeces from pigs from 2 villages. All of the group A rotaviruses examined had the same electrophoretype and this was distinct from that of the common type infecting humans in the area at the time of the study. None of the group A positive samples reacted with monoclonal antisera specific for human group A rotaviruses of serotypes 1, 2, 3, 4, or 8. The non-group A rotaviruses also all had identical electrophoretypes. In contrast to previous findings in intensive piggeries, rotavirus infection did not occur in all young pigs and was not limited to young animals under 2 m of age. Infected pigs varied in age from 12 days to 20 weeks of age. This pattern of infection was attributed to the non-intensive husbandry situations in the villages, with less opportunity for transmission to occur than in intensive piggeries.  相似文献   
14.
SUMMARY Twenty-four of 57 calves fed a diet containing 33% cotton seed meal (CSM) died between 7 and 15 weeks of age. Initial deaths were not accompanied by premonitory signs, but after CSM withdrawal most calves developed rough coats, anorexia, weakness, ascites and subcutaneous oedema. Those that died had large volumes of serous fluid in the body cavities, hard livers of ‘nutmeg’ appearance, and pulmonary congestion. Histopathologically the livers showed periacinar necrosis in acute cases and periacinar fibrosis in chronic cases. Lungs from several calves had oedema, haemosiderosis and fibrosis in some pulmonary vessels. Atrophy of myocardial fibres was present in most cases. The concentration of free gossypol in the diet was 100 to 220 mg/kg. Ante-mortem and post-mortem findings supported a diagnosis of gossypol poisoning. The deaths continued for 4 weeks after withdrawal of CSM from the diet.  相似文献   
15.
A total of 31 isolates of Haemophilus parasuis obtained from Australian pigs were serotyped by the Kielstein-Rapp-Gabrielson scheme. The isolates were assigned to serovar 1 (1 isolate), serovar 2 (1 isolate), serovar 4 (4 isolates), serovar 5 (7 isolates), serovar 9 (2 isolates), serovar 10/7 (4 isolates), serovar 12 (1 isolate) and serovar 13 (6 isolates). The remaining 5 isolates could not be assigned to a serovar. Two different serovars (5 and 13) were detected in one herd. The only 2 isolates obtained from clinically normal pigs (from the same herd) were serovar 9. The common serovars were isolated from pigs with pneumonia as well as from pigs with conditions of the Glässer's disease type. The serological heterogeneity amongst Australian isolates of H parasuis has important implications for the use of vaccines to control Glässer's disease.  相似文献   
16.
The experimental ascertainment of the pure feed protein flowing into the duodenum on the basis of the calculation of the difference between the NH3-free crude protein flowing into the duodenum and the bacterial crude protein determined by means of DAPA showed the following results after the testing of 28 different rations at a dry matter intake adequate to the production level: With a variation of the pure protein in the crude protein content of the ration between 40 and 90%, the quota of feed protein flowing into the duodenum is 52.5%, and with a variation of the pure protein in the crude protein content between 80 and 90% it is 40.6%. The quota of feed protein flowing into the duodenum shows a negative correlation to the apparent digestibility of the organic matter (y=231.7 -2.52x +/- 14.5). With a DM-intake adequate to the production level the quota of feed protein flowing into the duodenum is neither influenced by the flow rate (kg digesta/kg DM-intake) nor by the 'dilution rate' (g bacteria-free DMD/kg live weight 0.75/h).  相似文献   
17.
This study investigated and compared quantitative and semi-quantitative coronary lesion evaluation in Atlantic salmon, Salmo salar. A total of 121 immature farmed and 47 sexually mature wild Atlantic salmon were included. Coronary arteries from all fish were morphometrically evaluated using a semi-quantitative method. A subsample of 76 salmon was additionally evaluated using a quantitative method. Another subsample of 71 salmon was used for reliability testing of the semi-quantitative method. Ten cross-sections of coronary arteries located on the ventral surface of the bulbus arteriosus were semi-quantitatively scored with regard to myointimal coronary lesions. Quantitative measurements comprised maximal intimal thickness and area lesion (%) while semi-quantitative measurements comprised maximal intimal thickness and lesion degree (%). Scores for individual fish were expressed as the average of lesion score, denoted as mean range lesion. One person performed all evaluations blindly. Two pathologists tested repeatability of the semi-quantitative lesion score measurements blindly. Both semi-quantitative and quantitative variables increased significantly with increasing lesion score. Semi-quantitative estimation gave significantly higher maximal intimal thickness values than quantitative measurement. Semi-quantitative measurements were found to explain 63.2% of variation in quantitatively measured maximal intimal thickness. Due to lack of agreement, the two methods are not directly comparable and one method cannot replace the other. Repeatability within and between observers with regard to semi-quantitative classification was very good with Kappa values larger than 61.5%. The semi-quantitative method was a valid and reliable method for coronary lesion evaluation in Atlantic salmon.  相似文献   
18.
The purpose of this study was to investigate the nature of variably sized pigmented foci encountered in fillets of farmed Atlantic salmon, Salmo salar L. The material was sampled on the fillet production line and on salmon farms from fish with an average size of 3 kg from various producers. The fish had been routinely vaccinated by injection. Gross pathology, histology, immunohistochemistry using antisera against major histocompatibility complex (MHC) class II beta chain and transmission electron microscopy (TEM) were used to characterize the changes. Macroscopically, melanized foci were seen penetrating from the peritoneum deep into the abdominal wall, sometimes right through to the skin, and also embedded in the caudal musculature. Histological investigation revealed muscle degeneration and necrosis, fibrosis and granulomatous inflammation containing varying numbers of melano-macrophages. Vacuoles, either empty or containing heterogeneous material, were frequently seen. The presence of abundant MHC class II+ cells indicated an active inflammatory condition. TEM showed large extracellular vacuoles and leucocytes containing homogeneous material of lipid-like appearance. The results showed that the melanized foci in Atlantic salmon fillet resulted from an inflammatory condition probably induced by vaccination. The described condition is not known in wild salmon and in farmed salmon where injection vaccination is not applied.  相似文献   
19.
In an individual feeding experiment with 48 Holstein-Friesian heifers divided into 3 groups, the effect of various energy levels on live weight development and energy expenditure in the age bracket of 97 days (78 kg live weight) to conception (350 kg LW) and from conception to calving (500 kg LW) was investigated. Rations with differing concentrate--roughage ratios were used. The differentiation of energy intake per day between groups 1 and 2 and group 3 amounted to 7.5% in the 1st development period and to 20% between group 1 and groups 2 and 3 in the 2nd development period. There were significant differences in the live weight gain of 95 g/animal and day in the first development period (up to conception) and of 81 g/animal and day in the second period of development (from conception to calving). Under the tropical climatic conditions the energy expenditure in these studies was approximately 10% under the energy expenditure recommended by the NRC (1978). While there was a clear reciprocal relation between energy expenditure and live weight gain in the first period of development, this relation was less distinct in the second period of development.  相似文献   
20.
The effect of footrot on body weight and wool growth of sheep   总被引:1,自引:0,他引:1  
Body weight and traits associated with production of wool were measured over a 2-year period between 1985 and 1987 in south-western New South Wales in a flock of Merino wethers experimentally infected with footrot. The disease was allowed to spread freely amongst 150 of the flock but kept at very low prevalence in the remaining 50 by preventive footbathing during transmission periods. Severe, underrunning footrot had a significant adverse effect on body weight, for each year of the trial. Body weight was most severely reduced at times of the year when footrot was spreading among animals and lesions were severe. The mean body weight of the infected group at the end of the 2 years of observation was 7.3 kg (11.6%) below that of the control group. Footrot also depressed wool growth, with the mean clean fleece weight of the infected group being 0.4 kg (8%) lighter than that of the controls at each of the 2 annual shearings. There were no consistent differences between the groups for the other wool characteristics measured.  相似文献   
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