The effect of recombinant swine interleukin-4 on swine immune cells and on pro-inflammatory cytokine productions in pigs

The in vitro effect and the in vivo influence of recombinant swine IL-4 (rSwIL-4) were characterized in various swine cells and in nursery pigs on LPS-induced endotoxic shock and pro-inflammatory cytokine productions. In in vitro experiment, the rSwIL-4 induced a proliferation of CD4 positive T cells in mitogen-prestimulated peripheral blood mononuclear cell (PBMC). In addition, the rSwIL-4, which was produced from insect cells, promoted the differentiation of monocytes into immature dendritic cells in combination with granulocyte macrophage-colony stimulating factor (GM-CSF). Furthermore, the rSwIL-4 successfully suppressed the LPS-induced secretion of TNF-alpha, IL-1alpha, IL-6, IL-8, and IL-18 from swine alveolar macrophages when rSwIL-4 was treated at the same time with LPS. In in vivo experiment in nursery pigs, subcutaneous pretreatment of rSwIL-4, which was produced from baculovirus expression system, enhanced the severity of respiratory failure with endotoxic shock, and increased the production of TNF-alpha and IL-18 in response to inoculation with LPS. These results indicate that the rSwIL-4 is biologically active in both in vitro and in vivo treatments. Depending on the administration time, pro-inflammatory cytokine productions by IL-4 can cause either inhibitory or stimulatory regulation.     

BSE in the Netherlands: an update

Up to 2006, there have been 82 cases of BSE in cattle born in the Netherlands. This article reviews the current situation regarding BSE in the Netherlands and summarizes the clinical symptoms of the disease. Data from the Netherlands show that a passive surveillance system, by which farmers and veterinarians have to report suspect clinical cases, has a low sensitivity. The epidemiology of, and risk factors for, BSE are discussed. All the Dutch cases of BSE can be attributed to cross-contamination of feed with meat-and-bone meal. On the basis of information about the epidemic and the cases reported to date, it is anticipated that the number of cases of BSE will continue to decline in the Netherlands and Europe. The European Commission has presented a road map that describes how the European BSE policy can be changed in the short and long term if the current favourable trend in BSE cases continues. It is time for a new phase in the management of BSE but with continued protection of the public's health and eradication of BSE.     

Porcine myelomonocytic markers: summary of the second international swine CD workshop

Forty five mAbs submitted to the Second International Swine CD workshop were analyzed by six different laboratories for their possible reactivity with porcine myelomonocytic cells using flow cytometry and immunohistochemistry. As a result of these analyses, a new swine workshop cluster, SWC9, composed of two mAbs that recognize an antigen selectively expressed on mature macrophages, was defined. In addition, several mAbs were identified, allowing the differentiation of granulocytes from monocytes/macrophages, or monocytes from macrophages. Further work is required to identify the antigen recognized by these mAbs. Nevertheless, they should already prove useful for the identification of different stages in the macrophage maturation/differentiation, and will certainly aid analyses on the complexity of the mononuclear phagocyte system in the pig. Finally, the cross-reactivity of three anti-human CD14 mAbs with porcine myelomonocytic cells was established in this workshop.     

BALB/c鼠口服免疫猪水肿病大肠杆菌基因突变菌株的免疫效果

为了研究猪水肿病(ED)大肠杆菌SLT-Ⅱe基因突变菌株作为口服疫苗的免疫效果,本实验用已构建的猪ED大肠杆菌SLT-Ⅱe基因突变菌株口服免疫BALB/c小鼠,检测其血清中的IgG抗体及粪便和肠黏液中的slgA抗体水平,并进行淋巴细胞增殖检测及攻毒保护实验.结果表明该基因突变菌株具有良好的免疫性,能诱导小鼠体内产生IgG和sIgA抗体,并且能引起T淋巴细胞增殖反应.攻毒保护实验结果显示,口服免疫突变菌株能对小鼠提供良好的保护,保护率为75%(15/20).本研究结果证明,该大肠杆菌基因突变菌株在小鼠体内能激发体液免疫和细胞免疫反应,可作为猪ED口服疫苗的候选菌株.     

Bovine paratuberculosis: an update

Paratuberculosis is enzootic in the Great Lakes region and northeast US, causing severe economic losses. Sheep, pigs and deer can serve as intermediate hosts. Diagnosis is difficult and there is no entirely satisfactory serodiagnostic test. While treatment is generally considered ineffective, vaccines have been used successfully for prevention. Measures that can be taken in herds to reduce losses include raising replacement animals separate from adults, slaughtering animals shedding M paratuberculosis in their feces, and decontaminating the premises.     

Canine ehrlichioses: an update

The development of molecular biology techniques and methods for the isolation and growth of ehrlichias in tissue culture have greatly facilitated the study of these organisms. The available knowledge on ehrlichias is thus rapidly increasing and in this review recent findings on the epidemiology, transmission, clinical and laboratory signs of infection, diagnosis and treatment of canine ehrlichioses are described.     

Diabetes mellitus: an update

Diabetes mellitus is characterized by disturbances of carbohydrate, lipid and protein metabolism and glucose intolerance. Several factors are known to contribute to the disease, ie, obesity, immune-mediated insulin resistance, and the diabetogenic hormones glucagon, growth hormone and glucocorticoids. Recently, a number of developments have taken place in the management of human diabetes mellitus which may be applicable to dogs and cats. These include the use of diets high in soluble, non-absorbable carbohydrates which lower post-prandial increases in blood glucose. The more complex causes of instability, ie, insulin-induced hyperglycaemia, rapid metabolism of insulin and insulin resistance can be diagnosed by hospitalizing the patient and measuring blood glucose at four hour intervals for 24 hours. In human medicine, new techniques for controlling diabetes mellitus are pancreatic implants, constant infusion pumps for insulin and the use of the hormone somatostatin which suppresses glucagon secretion, but not all may be applicable to veterinary medicine.     

Sulfa residues in pork: an update

Sulfamethazine (SMZ) is an antibacterial drug used in approximately 75% of all hogs marketed in the U.S. The tolerance for residues of SMZ in uncooked tissues is .1 ppm, and the withdrawal time is 15 d. The rate of illegal residues in swine from the use of SMZ has continued to fluctuate between 4% and 5% from 1980 through 1987. This was not acceptable. The Center for Veterinary Medicine (CVM) also has received from the National Center for Toxicological Research a report showing that SMZ produces a dose-related increase in follicular cell adenomas of the thyroid gland in rats and mice. The FDA has discovered three major causes of SMZ residues by investigating violators. The number one cause was a lack of sequencing, flushing, and cleaning of mixer equipment. Failure to follow withdrawal times was another major cause, and the third major reason was the use of a soluble powder solution. At least 16% of SMZ residue violations have resulted in no follow-up due to lack of animal identification. The FDA district offices are conducting on-farm investigations of swine producers who have caused SMZ violations. Repeat violators and those that produce higher residue levels will receive a higher priority. The FDA currently is attempting to obtain more state support, particularly for investigation of first-time violators. The CVM is serious about resolving the SMZ residue problem.     

复方中草药止泻散对猪免疫功能的影响

复方中草药制剂止泻散,通过临床实验已经证明其对仔猪黄白痢具有良好的防治效果,为了从其对猪体免疫力的影响方面探讨作用机理,给试验猪灌服不同浓度的止泻散煎剂（0.5g/ml、1．0g／ml、1.5g／m）,观察用药后不同时间（0、3、7、10、14、20d）猪的T淋巴细胞百分率的变化情况。     

Xylazine-ketamine-oxymorphone: an injectable anesthetic combination in swine

A xylazine, ketamine, and oxymorphone combination was investigated to determine its effectiveness as an injectable anesthetic regimen for use in swine. The combination was found to provide good narcosis, analgesia, and muscle relaxation, and was considered to be adequate for minor surgery. The intravenous dose rate was xylazine, 2mg/kg; ketamine, 2mg/kg; and oxymorphone, 0.075mg/kg. The dose of each component was doubled when the intramuscular route was used.     

Dilated cardiomyopathy: an update.

Despite many advances in he diagnosis and treatment of DCM, it continues to be an important cause of cardiovascular morbidity and mortality in large-breed dogs. In the coming years, it is hoped and anticipated tht further discoveries will be made in the areas of etiology, therapy, and assessment of prognosis, ultimately with a view to having a greater impact on the clinical management of these cases.     

Canine pulmonary angiostrongylosis: an update

Canine pulmonary angiostrongylosis is an emerging snail-borne disease causing verminous pneumonia and coagulopathy in dogs. The parasite is found in Europe, North and South America and Africa, covering tropical, subtropical and temperate regions. Its distribution has been characterised by isolated endemic foci, with only sporadic occurrences outside these areas. In the last two decades, the literature has been dominated by several case reports and small case series describing sporadic disease in old or new endemic areas. Case reports and experimental studies with high doses of infective third stage larvae may not reflect what happens under field conditions. There is insufficient understanding of the spread of infection and the dynamic consequences of this parasite in the canine population. This review discusses the biology, epidemiology, clinical aspects and management of canine pulmonary angiostrongylosis.