Host immune responses against hog cholera virus in pigs treated with an ionized alkali mineral complex

To determine the immune responses in pigs to hog cholera virus after treatment with an ionized alkali mineral complex (IAMC), 40 healthy pigs (28-32 days old) from a commercial swine farm were purchased and housed into 4 groups (n=10 each). All pigs were vaccinated intramuscularly (1 ml) with an attenuated live hog cholera virus (HCV, LOM strain) at 28-32 days old and challenged with a virulent hog cholera virus at 8 weeks after vaccination. Each group was treated with PowerFeel sprayed diet as 0.05% (w/w) in a final concentration (T-1, n=10), a diet mixed with SuperFeed as 3% (w/w) in a final concentration (T-2, n=10), or a diluted PowerFeel solution (1:500, v/v) as drinking water (T-3, n=10), respectively. A group (n=10) served as a non-treated control. Proportions of expressing CD2+ and CD8+ cells increased significantly (p<, 0.05) at 8-week post-application. Mean antibody titers of each group against HCV gradually increased to higher levels after vaccination and with challenge of the virulent virus. In conclusion, the IAMC-treated diets can be helpful for the improvement of growth in pigs with proper vaccination program, while the IAMC-treated diets have no effects on the clinical protection against hog cholera.     

Isolation of Neospora caninum from the brain of a naturally infected adult dairy cow

Neospora caninum was isolated from the brain of a 2-year-old dairy cow that had aborted confirmed N. caninum-infected fetuses on two occasions. The cow had an indirect fluorescent antibody titer of 1:1600 to N. caninum. The cow was killed 24 days after its second abortion and the brain was bioassayed for N. caninum in nude mice. Multifocal areas of perivascular cuffing and glial nodules were observed in the cerebrum and mesencephalon of the cow, but N. caninum was not identified in histological sections of the brain. All three nude mice inoculated with brain homogenate of the cow, developed emaciation and paralysis. Microscopical examination of the nude mice revealed systemic N. caninum infection with demonstrable tachyzoites in various organs. The parasites isolated from fresh mouse brain were transferred successfully into Vero cell cultures. PCR procedure on the purified tachyzoites obtained from the Vero cell cultures amplified the specific DNA sequence for N. caninum.     

Comparison of response to immunotherapy by intradermal skin test and antigen-specific IgE in canine atopy

The intradermal skin test (IDST) and serologic allergy test (SAT) has been developed for confirming a diagnosis of canine atopy and determining allergens for immunotherapy. To determine the prevalence of causative allergens for canine atopic dermatitis in Japan, IDST and SAT were performed with the CMG Immunodot strips on 95 atopic dogs using 9 allergens. In addition, we compared agreement rate, sensitivity and specificity between them (using IDST as the standard). The allergen most commonly positive in both tests was house dust mites (IDST: 69.5%, SAT: 48.4%). Moreover, Japanese cedar, mugwort and grass mix were detected as attendant causative allergens. Agreement rates between the two tests ranged from 67.4% to 96.8%; the overall mean agreement rate were 81%. SAT was shown to have sensitivity to IDST ranging from 16.7 to 68.2%. The specificities were very high for all allergens, on the order of 94.9-100% (median=98.7%). Finally, the efficacy of immunotherapy was evaluated on 27 atopic dogs based on IDST (15 dogs) and SAT (12 dogs) results. Overall, 60% (9/15) of the IDST group and 66.8% (8/12) of the SAT group experienced a 50% to 100% reduction in their symptomatology. No significant differences were found in response to immunotherapy during the follow-up period between allergen selection methods. These results indicate the value of serologic tests as an aid to identifying an allergen solution for immunotherapy.     

Farmers' attitudes towards techniques for improving oestrus detection in dairy herds in South West England

Unidentified heats contribute to declining fertility rates in English dairy herds. Several techniques have been advocated to improve heat detection rates. Despite demonstrable technical efficacy and cost-effectiveness, uptake is low. A study in South West England used the Theory of Reasoned Action (TORA) to explore dairy farmers' attitudes and beliefs towards heat detection techniques. Few farmers were convinced that following prescribed observation times, milk progesterone testing and using pedometers would fit their system or improve on their current heat detection practices. Perceived difficulty of using a technique was not a constraint on adoption. Without promotion that addresses identified barriers and drivers to adoption, little change in current practice can be expected.     

Effect of soil water stress on the development of stone cells in pear (Pyrus pyrifolia cv. ‘Niitaka’) flesh

This study was carried out to investigate the cause of stone cell formation in pear (Pyrus pyrifolia cv. ‘Niitaka’) flesh. Potted plants grown in a glass house were subjected to water stress conditions without irrigation for 30 days from 30 days before full bloom (BFB treatment), full bloom (FB treatment) and 30 days after full bloom (AFB treatment). Control plants were drip-irrigated daily maintaining a soil matrix potential around −40 ± 5 kPa. The formation of stone cells in pear flesh increased in the FB treatment and AFB treatment plants and this tendency was sustained until the harvest season. Root activity was investigated 60 days after full bloom (DAFB) and the triphenyltetrazolium chloride (TTC) reduction potential, the formazan content and leaf water potential were investigated 30, 45, and 60 DAFB. Root activity decreased progressively due to the effect of water stress. Also, the Ca content in leaf and flesh was lower. The peroxidase activity was high in the flesh at the early stages of fruit growth and decreased at the late stages of fruit growth, and then a higher increase of peroxidase activity was observed in water-stressed fruit. The reduction in calcium content of leaf and fruit in plants under water stress may be related to the reduction of root activity and leaf water potential. The increase in peroxidase activity under water stress may be due to limited calcium absorption. Higher peroxidase activity may induce the accumulation of lignin in the cell wall and promote the formation of stone cells in pear flesh. We conclude that water stress condition during the early stages of fruit growth is one of several factors that determine the formation of stone cells in pear flesh.     

工厂化繁育香菇胶囊菌种专用培养基配方研究

在已筛选出的代料香菇胶囊菌种专用配方LSC1和LSC5基础上,设计了7种香菇胶囊菌种培养基配方,以L26为供试菌株,观察测试了菌丝生长速度、瘤状突起物形成时间与数量、菌种成型及在愈伤培养时的特征以及菌种持水性等特征指标,筛选出了适宜于工厂化繁育香菇胶囊菌种的专用培养基配方LSCG2T和LSCG3,并在胶囊菌种工厂化繁育生产线中进行了应用试验,取得了良好效果。试验结果表明,工厂化繁育胶囊菌种的配方中粗细木屑的比例应提高到5∶1,配方中应添加以提供微量元素和基质物理性能改良剂的辅料。     

Selective growth-inhibiting effects of compounds identified in Tabebuia impetiginosa inner bark on human intestinal bacteria

The growth-inhibiting activity of anthraquinone-2-carboxylic acid and lapachol identified in the inner bark of taheebo, Tabebuia impetiginosa, toward 10 human intestinal bacteria was evaluated by using a paper disk diffusion bioassay and compared to those of seven lapachol congeners (1,4-naphthoquinone, naphthazarin, menadione, lawsone, plumbagin, juglone, and dichlone) as well as two commercially available antibiotics, chloramphenicol and tetracycline. Anthraquinone-2-carboxylic acid exhibited very strong growth inhibition of Clostridium paraputrificum at 1 microg/disk while 100 microg/disk of lapachol was needed for moderate growth inhibition of the same organism. These two isolates exhibited weak inhibition of Clostridium perfringens and Escherichia coli at 100 microg/disk while no adverse effects were observed on the growth of Bifidobacterium adolescentis, Bifidobacterium bifidum, Bifidobacterium infantis, Lactobacillus acidophilus, and Lactobacillus casei at 1000 microg/disk. Structure-activity relationships indicate that a methyl group in the C-2 position of 1,4-naphthoquinone derivatives might play an important role in antibacterial activity.     

Evaluation of adverse reactions in dogs following intravenous mesenchymal stem cell transplantation

Background

Recent studies have assessed the therapeutic potential and drawbacks of mesenchymal stem cells (MSCs). The adverse reactions of intravenous transplantation of bone marrow (BM)-derived MSCs were examined at varying doses and frequencies of administration.Nine healthy beagle dogs were purchased from a commercial laboratory. The dogs were distributed equally (n = 3 per group) and randomly into three groups. All dogs received allogeneic BM-derived MSCs: 2 × 10⁶ once (group A), 2 × 10⁷ once (group B), and 2 × 10⁶ for three consecutive days (group C). Various laboratory examinations, multi-detector computed tomography features and histopathology were evaluated to clarify the clinical and diagnostic features of adverse reactions of MSCs administration, prior to receiving MSCs (pre procedure) and on days 1, 3, and 7 post transplantation.

Results

Only one dog had clinical signs during and after MSCs transplantation. Dogs receiving 2 × 10⁶ MSCs showed increased numbers of lymphocytes but the total white blood cell counts were not elevated (P < 0.01). Multi-detector computed tomography (MDCT) revealed pulmonary parenchymal changes in one dog and histopathologic examination revealed pulmonary parenchymal edema and hemorrhage in four dogs. The presence of pulmonary thromboembolism was not detected in either examination.

Conclusions

We considered the presence of pulmonary edema and hemorrhage as possible adverse reactions after intravenous MSCs transplantation; however these results should be cautiously interpreted.     

The effects of enrofloxacin on canine tendon cells and chondrocytes proliferation <Emphasis Type="Italic">in vitro</Emphasis>

Enrofloxacin, a fluoroquinolone antibiotic has been used widely in humans and domestic animals, including dogs, because of its broad-spectrum activity and relative safety. The side effects of fluoroquinolone, induced tendinopathy, tendonitis, spontaneous tendon rupture and cartilage damage, remain incompletely understood. In the present study, we investigated the in vitro effects of enrofloxacin on cell proliferation and induction of apoptosis in canine Achilles tendon cells and chondrocytes. Cell growth and proliferation after treating with enrofloxacin for 2–6 days was quantified by a colorimetric 2,3-bis{2-methoxy-4-nitro-5-sulfophenyl}-2H-tetrazolium-5-carboxyanilide inner salt (XTT) assay. The results showed that enrofloxacin could inhibit the proliferation of canine tendon cells and chondrocytes at increasing concentrations (10–200 μg/ml). The inhibition of proliferation of canine tendon cells and chondrocytes after exposure to enrofloxacin were associated with induction of apoptosis, as evidenced by the typical nuclear apoptotic condensed nuclei found using Hoechst 33258 staining. It was demonstrated that canine tendon cells and chondrocytes treated with 200 μg/ml enrofloxacin for 4 days exhibited apoptotic features and fragmentation of DNA. Enrofloxacin also increased the apoptosis of canine tendon cells and chondrocytes in a dose and time-dependent manner. The results indicate that enrofloxacin inhibits cell proliferation, induces apoptosis and DNA fragmentation, which might explain enrofloxacin-induced tendinopathy and cartilage damage.