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41.
犊牛腹泻的病因、诊断及综合防治   总被引:1,自引:0,他引:1  
介绍了犊牛腹泻的流行病学、发病原因及临床症状,并对该病的实验室诊断、治疗及综合预防措施进行了综述。  相似文献   
42.
犊牛开食料研究报告   总被引:1,自引:0,他引:1  
设计了一种犊牛开食料配方,干物质营养成分为:代谢能13.0MJ/kg、粗蛋白21%、钙1.1%、磷0.56%,铁110mg/kg、锰133mg/kg、铜33mg/kg、锌167mg/kg、碘1.4mg/kg、硒0.88mg/kg、钴1.1mg/kg、维生素A 11000 IU/kg、维生素D_32780 IU/kg、维生素E 133 IU/kg。20头新生犊牛经配对试验采食按该配方生产的饲料。结果发现,试验组犊牛的平均日耗料量极显著增加40g(P<0.01),另外腹泻发生率显著降低(P<0.05)。而犊牛血清钙、磷、铁、葡萄糖和总蛋白的浓度都在正常范围之内。试验表明,该颗粒料适口性良好,可以促进犊牛的采食和断奶,并可减少腹泻的发生。  相似文献   
43.
选用碳纤维作为食管代替物,对各切除颈段固有食管3~4cm的8例绵羊和2例犊牛行食管植入吻合术。植入的碳纤维人工食管长度为3~4.5cm,管径为1~2cm,管壁厚为0.1~0.15cm。人工食管与食管断端采用作者改进的高桥氏二层重叠缝合方法吻合。术后除2例绵羊因人工食管渗漏子第4d死亡外,其余吻合手术均获成功。绵羊术后4~5d采食咀嚼碎青草自如,但咽下较缓慢,有时反复2~3次方能咽下;术后5~20d,采食及吞咽恢复至正常状态;20d后又复出现吞咽缓慢。犊牛术后饮奶咽下顺利,到20d后偶有反复吞咽和奶汁由鼻孔中返流现象,经3~5d恢复正常。经X线透视或钡剂食管造影检查,术后7~14d,钡液顺利通过食管和人工食管,显示人工食管部较正常食管稍细,术后22~26d,人工食管脱落,脱落部食管狭窄,其前方食管呈纺锤状扩张。动物全身及血液,生化指标观察均无明显改变。病理学观察,术后15d可见在食管两断端由新生肉芽组织形成纤维膜管以包裹人工食管,在新生肉芽组织纤维膜管内面,靠近食管吻合口边缘,已长出灰白色薄层粘膜;术后22~25d,人工食管脱落于瘤胃或网胃中,食管缺损段已由新生的食管组织连接在一起,新生食管外周形成纤维膜包裹,管腔内面被覆有较完整的薄层粘膜;术后35~40d。见新生食管内面粘膜层覆盖完整,管壁稍增厚,内腔稍  相似文献   
44.
Fortytwo calves, 28 to 117 days old, were collected from 23 dairy farms and transported in a lorry, allowing direct contact between the calves, to 8 calf rearing farms. The average transport time per calf was 4.5 h, ranging from 0.3 to 12.8 h. The calves were sampled by nasal swabbing for mycoplasmas first before loading and then immediately after transport. Thirteen of the calves were transferred to farm I. They were placed in individual pens in a separate room to themselves, and were sampled at intervals for a period of 4 weeks.Ten of the 42 calves (23.8 %) originating from 5 of the source farms were found initially positive for M. dispar with titers > 4 log10 ecu; 3 of these 10 calves were delivered to farm I and 7 calves to 6 others of the 8 receiving farms. Three initially infected calved delivered to farms I continued to be positive throughout the follow-up period; among the 10 initially negative calves the frequency of detected infection, and the geometric mean titer (within parenthesis), developed so that on days 1, 7, 14, and 28 the figures were: 2 (2.5), 8 (4.3), 9 (4.7), and 10 (5.5), respectively.After transport 3 initially negative calves were found positive with low titers. Two of them were placed on farm I. In one of them positivity proved to be only transient; the case seems to represent a phenomenon of transfer of mycoplasmas without establishment of infection. In contrast, at least 4 (possibly 7) calves, negative both before and after transport–ascribed above to the group of 10 initially negative calves arriving on farm I–had in all likelihood caught the infection during the transport. Two of the 10 calves most likely caught the infection on the farm; for 3 calves the evidence was equivocal as to the 2 alternatives.Seven of the 42 calves (16.7 %) were found to be initially infected with M. bovir-hinis, 2 of the 42 with Acholeplasma laidlawii. Among the 13 calves transported to an reared on farm I, 8 were found to be positive at least once for M. bovirhinis during the study. Colonisation by this mycoplasma was partly detected only intermittently and the detectable prevalence among the 13 calves at its highest was only 38.5 %.  相似文献   
45.
将69头肺炎奶犊牛分成3组,分别为24,25和20头,分别应用双莴连注射液。氨基苄青霉素和恩诺沙星进行治疗,治愈率分别为62.5%,,68.0%和90%,治愈时间分别为11.3±1.20,9.8±1.4和4.4±1.1d。治疗结果表明恩诺沙星组的治疗效果明显优于另外2组,该药可作为治疗犊牛肺炎的首选药物。  相似文献   
46.
Immuno-adjuvants like MDP or levamisole inoculated in the calf through general route increase the respiratory mucosa response to the irradiation inactivated IBRV.

We have shown from the 2nd day of the inoculation an interferon activity in the nasal mucus. This interferon partially destroyed at pH2 and at 56°C, persists in the respiratory fluids for one week. It is never found in the sera of the animals.

This inactivated virus given through nasal route does not stimulate antibody production in the local system or in the serum.

The dose of levamisole administered is critical: 5 mg/kg are the minimal quantity required to give a favourable answer whereas the 2.5 mg/kg normally used are without effect.

The interferon presence in the respiratory fluids gives a satisfactory interpretation of the good resistance to respiratory infection obtained in 500 calves with this treatment: inactivated virus by nasal route and immuno-adjuvant by intradermic or intramuscular route.  相似文献   

47.
A prospective study was carried out on 92 randomly selected beef herds in the Midi-Pyrénées region in France. The objective was to determine factors associated with time to neonatal gastroenteritis. By taking into account the “intra-herd” correlation in failure time (in the semiparametric Cox model), we identified 12 management risk factors associated with hazard of diarrhoea. Some previously have been identified, but “new” risk factors were feeding of corn silage and the incidence of diarrhoea in the last season. We used the two main approaches which are often reviewed: marginal and frailty Cox models. Our results show that these two models give different parameter estimates, so the choice of the model remains crucial.  相似文献   
48.
This study elucidated the effects of limited concentrate feeding on growth, nutrient digestibility, blood profile and gene expression of gluconeogenic enzymes in the liver of dairy calves. The study utilized 36 German Holstein dairy calves (5-7 days of age) divided into two groups of 18 calves each for 150 days. Control group calves received 2 kg/(calf × day) of concentrate, whereas calves in the restricted group received only 1 kg/(calf × day). Good quality forage (mixture of maize and grass silages) was available for ad libitum consumption to both groups. The intake of milk replacer before weaning, and of concentrate were recorded daily per calf; however, the consumption of forages was quantified as daily average of the group. Body weights (BW) were recorded at start and on days 35, 70, 112 and 150. Blood and serum samples and spot urinary and faecal samples were also collected at similar time points. On days 70 and 150, liver biopsies were collected from seven animals in each group. The BW was not different between the groups at all times. Total BW gain in the control group was 124 kg as opposed to 111 kg in restricted group that led to average BW gain of 827 g/day and 739 g/day in respective groups, and the differences were significant (p = 0.018). As planned, the control group had higher concentrate and lower forage intake than the restricted group. The blood haemoglobin, haematocrit and serum variables (glucose, total protein, albumin and urea) were within the normal range in both groups, but serum glucose was higher (p < 0.05) in control than in restricted group at 70 days. There was no difference between groups in organic matter (OM) digestibility which declined (p < 0.001) with increasing age in both groups. Microbial crude protein (MCP) synthesis estimated from urinary allantoin excretion increased (p < 0.001) in both groups with increasing age but was not different between groups. The mRNA expressions for the gluconeogenic enzymes, cytosolic and mitochondrial phosphoenol pyruvate carboxykinase (EC 4.1.1.32) and pyruvate carboxylase (EC 6.4.1.1) measured by quantitative real-time PCR in liver biopsies showed no differences between groups. Overall, restricting concentrate moderately reduced the growth intensity without affecting the normal serum and blood indices, and MCP synthesis and OM digestibility showed no differences between groups, indicating that both concentrate feeding schemes can be successfully applied.  相似文献   
49.
从陕西杨凌某发病牛场采取腹泻犊牛病料5份,经微生物学诊断,从中分离出革兰阴性疑似致病菌6株。经生物学特性和生理生化试验鉴定,6株分离菌均为致病性大肠埃希菌。对分离菌进行抗生素敏感性试验,结果表明,该致病菌对氯霉素、菌必治、氧氟沙星、阿米卡星及卡那霉素等高度敏感;对妥布霉素、呋喃妥因和复达欣等中度敏感,对链霉素、庆大霉素、利福平、复方新诺明、四环素及红霉素等有较强的耐药性。动物致病性试验结果表明,该菌对小鼠有强致病性。  相似文献   
50.
Objective The purpose of this study was to determine the cardiovascular effects of sevoflurane in calves. Study design Prospective experimental study. Animals Six, healthy, 8–12‐week‐old Holstein calves weighing 80 ± 4.5 (mean ± SEM) kg were studied. Methods Anesthesia was induced by face‐mask administration of 7% sevoflurane in O2. Calves tracheae were intubated, placed in right lateral recumbency, and maintained with 3.7% end‐tidal concentration sevoflurane for 30 minutes to allow catheterization of the auricular artery and placement of a Swan‐Ganz thermodilution catheter into the pulmonary artery. After instrumentation, administration of sevoflurane was temporarily discontinued until mean arterial pressure was > 100 mm Hg. Baseline values were recorded and the vaporizer output increased to administer 3.7% end‐tidal sevoflurane concentration. Ventilation was controlled to maintain normocapnia. The following were recorded at 5, 10, 15, 30 and 45 minutes after collection of baseline data and expressed as the mean value (± SEM): direct systolic, diastolic, and mean arterial blood pressures; cardiac output; mean pulmonary arterial pressure; pulmonary arterial occlusion pressure, heart rate; and pulmonary arterial temperature. Cardiac index and systemic and pulmonary vascular resistance values were calculated using standard formulae. Arterial blood gases were analyzed at baseline, and at 15 and 45 minutes. Differences from baseline values were determined using one‐way analysis of variance for repeated measures with post‐hoc differences between mean values identified using Dunnet's test (p < 0.05). Results Mean time from beginning sevoflurane administration to intubation of the trachea was 224 ± 9 seconds. The mean end‐tidal sevoflurane concentration at baseline was 0.7 (± 0.11)%. Sevoflurane anesthesia was associated with decreased arterial blood pressure at all sampling times. Mean arterial blood pressure decreased from a baseline value of 112 ± 7 mm Hg to a minimum value of 88 ± 4 mm Hg at 5 minutes. Compared with baseline, arterial pH was decreased at 15 minutes. Pulmonary arterial blood temperature was decreased at 15, 30 and 45 minutes. Arterial CO2 tension increased from a baseline value of 43 ± 3 to 54 ± 4 mm Hg (5.7 ± 0.4 to 7.2 ± 0.3 kPa) at 15 minutes. Mean pulmonary arterial pressure was increased at 30 and 45 minutes. Pulmonary arterial occlusion pressure increased from a baseline value of 18 ± 2 to 23 ± 2 mm Hg at 45 minutes. There were no significant changes in other measured variables. All calves recovered from anesthesia uneventfully. Conclusion We conclude that sevoflurane for induction and maintenance of anesthesia was effective and reliable in these calves and that neither hypotension nor decreased cardiac output was a clinical concern. Clinical relevance Use of sevoflurane for mask induction and maintenance of anesthesia in young calves is a suitable alternative to injectable and other inhalant anesthetics.  相似文献   
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