Local intestinal immune response to Escherichia Coli heat-labile (LT) enterotoxin: LT antitoxin levels in healthy, diseased and antigen-fed pigs

With purified LT toxin and IgA, specific anti-LT enterotoxin activity was demonstrated in small intestinal contents of 27 pigs. After 60 days of age, rise in intestinal LT antitoxin titer was observed. Feeding LT containing E. coli antigen increased LT antibody levels in the intestinal secretions, but decreased antibody titers in sera. In post-weaning E. coli diarrhea LT antibody levels in intestinal secretions and sera decreased significantly. This phenomenon can be related to the occurrence of the frequently observed post-weaning E. coli diarrhea.     

Vaccination of pregnant cows with K99 antigen of enterotoxigenic Escherichia coli and protection by colostrum in newborn calves

The immune response to the K99 was tested in 45 pregnant cows, subcutaneously vaccinated, for protecting the newborn calves. Serological tests were performed in the blood sera of all animals and in the milk and colostrum sera; hemogram, inhibition of the adhesion to the brush border and histological tests were performed. The calves from vaccinated cows survived the experimental infection after the suction of colostrum in spite of the fact that the calves from control dams died with diarrhea.     

反刍动物肌内脂肪及脂肪酸调控研究进展

脂肪作为食物中必不可少的养分,它不仅可以提供能量,还可以提供必需脂肪酸。脂肪的硬度、贮存稳定性受肌内脂肪及脂肪酸组成等影响,进而影响脂肪的营养价值、风味以及食用品质,而脂肪酸组成受动物种类、品种、性别和日粮等因素影响。反刍动物由于瘤胃氢化作用导致其脂肪酸饱和程度和异构程度高于单胃动物,从而使其肌内脂肪以及脂肪酸组成不同,导致其肉品质以及风味都不同。本文旨在综述反刍动物肌内脂肪及其脂肪酸构成调控的研究进展。     

Hemotropic mycoplasmas infection in water buffaloes (Bubalus bubalis) from northeastern Brazil

Two species of hemotropic mycoplasmas (HM) are known to infect large domestic ruminants, Mycoplasma wenyonii and ‘Candidatus Mycoplasma haemobos’. Although HM has been described in cattle worldwide, data in water buffaloes (Bubalus bubalis) remain scarce. Accordingly, the aim was to determine the occurrence of HM in water buffaloes from northeastern Brazil. A total of 101/290 (34.83%) buffaloes were positive for HM (16 M. wenyonii alone, 6 ‘Ca. M. haemobos’ alone and 79 both). This was the first report of M. wenyonii infection in ruminants from Brazil. Clinical signs of hemoplasmosis in buffaloes remain unknown.     

CHLAMYDIA AVIUM DETECTION FROM A RING-NECKED PARAKEET (PSITTACULA KRAMERI) IN FRANCE

The crossing of host species barriers, through the spreading populations of introduced pet animals that become established in the wild, sets the stage for zoonotic pathogen (re)emergence. A literature review on pathogens that are hosted by the ring-necked parakeet (Psittacula krameri), a worldwide introduced pet, highlighted local infections of captive birds by chlamydial agents with high sanitary risk for human health in its introduced range. We searched for these pathogens through cloacal swabs collected from 85 individuals in an invasive population established in the suburban areas of Paris (Ile-de-France) from 5 localities during the winter seasons between 2011 and 2014. Based on quantitative PCR analysis, Chlamydiaceae shedding was detected at too low levels for species identification in 5 birds, but 1 parakeet (found dead) was positive for Chlamydiaceae typed as Chlamydia avium. The only known hosts recorded for C. avium in Europe are feral pigeons (Columba livia) and captive psittacines. This result raises the question of the sanitary risks associated with new pathogen transmission from exotic pets released in the wild, which could locally affect birds and potentially people who feed birds.     

小反刍兽疫病毒核衣壳蛋白抗原性与特异性的比较

为筛选建立小反刍兽疫病毒N蛋白双抗原夹心ELISA抗体检测方法的抗原原料,本研究通过优化大肠杆菌密码子、优化蛋白表达与纯化条件等方法,分别在pET-30a与pET-32a两个不同原核表达载体中成功获得了可溶性的小反刍兽疫核衣壳蛋白(N)。分别对重组大肠埃希氏菌pET-30a-(N)-BL21(DE3)株与pET-32a-(N)-BL21(DE3)株种子批的P7代与P20代进行蛋白诱导表达与抗原提取纯化,共获得6批小反刍兽疫病毒pET-30a-(N)蛋白与pET-32a-(N)蛋白,并对蛋白的浓度、纯度、抗原性和特异性进行检验。结果表明两个纯化后的重组抗原与羊小反刍兽疫病毒阳性血清有明显反应,具有较好的反应性,而与羊痘病毒阳性血清、羊口蹄疫病毒阳性血清、山羊关节炎/脑炎病毒阳性血清等特异性血清均无交叉反应,具有较好的特异性。本研究结果为今后以N蛋白为基础建立相应的抗原捕获ELISA方法,竞争ELISA检测方法、间接ELISA检测方法以及双抗原夹心ELISA抗体检测方法打下了坚实的基础。     

Difference in hydrophobicity of human and animal IgA.

We have used hydrophobic interaction chromatography on Phenyl-Sepharose CL-4B to compare the hydrophobicity of human IgA with the IgAs of eight animal species. The results suggest that the degree of difference between the various IgAs increases with increasing phylogenetic distance.     

Delivery of health and husbandry improvements to working animals in Africa

Problems have been identified in the delivery of extension messages about the maintenance of healthy and well-fed working animals. The different factors that need to be considered in developing effective disease control and prevention programmes for working oxen and equids including vector-borne diseases, helminth disease, and vaccination programmes have been reported and discussed and experiences in improving husbandry including footcare, harness, and worm management reported. Most draught animals are owned by people who lack the financial means to pay for or to access the information needed on nutritional supplements, vaccinations and drug treatment. Smallholder farms are often remote from veterinary services, thereby requiring greater emphasis on preventive measures and local remedies. Several NGOs have traditionally provided static and mobile treatment teams for equines and training courses for farriers and harness makers. The effectiveness and sustainability of these services and ways in which delivery of health care and husbandry messages could be delivered to improve impact are discussed.