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121.
The effect of antibody to caseous lymphadenitis in ewes on the efficacy of vaccination in lambs 总被引:1,自引:0,他引:1
MW Paton AR Mercy† SS Sutherland‡ TM Ellis‡ SR Duda§ 《Australian veterinary journal》1991,68(4):143-146
The effect of maternal antibody to the toxin of Corynebacterium pseudotuberculosis, produced by caseous lymphadenitis (CLA) in ewes or by vaccinating ewes before lambing, on the efficacy of vaccination against CLA in their lambs was examined. Lambs were allocated to treatments according to either the vaccination history of their dam or level of CLA toxin antibody of their dam. They were vaccinated twice using 2 different inoculation regimes and then artificially infected with CLA organisms. The number of lambs with CLA lesions was assessed at slaughter. In one experiment high levels of CLA toxin antibody activity in ewes were associated with decreased efficacy of CLA vaccination in their lambs, when lambs were vaccinated at 2 and 8 weeks or 8 and 14 weeks of age. In a second experiment the efficacy of lamb vaccination at 8 and 12 weeks, but not at 14 and 18 weeks of age, was decreased. In sheep flocks with a high prevalence of CLA, vaccinating lambs against CLA at less than 10 weeks of age may not produce optimum protection against CLA in lambs. There was no difference in infection rate between lambs from vaccinated and unvaccinated ewes. However, vaccination of lambs at 2 and 8 wks was less effective that vaccination at 8 and 14 weeks, probably due to reduced immunocompetence in young lambs. In sheep flocks where significant numbers of lambs receive their primary vaccination at less than 3 weeks of age vaccination programmes to control CLA in lambs may be less effective. 相似文献
122.
123.
A cat with granulomatous lymphadenitis due to Corynebacterium equi is described. Clinically the cat was diagnosed as having lymphosarcoma. Bacteria were cultured from the lymph nodes. 相似文献
124.
Johnson LR Fry MM Anez KL Proctor BM Jang SS 《Journal of the American Animal Hospital Association》2004,40(2):165-169
Systemic mycotic infections are typically localized to specific geographic regions of the country, because the organisms involved have certain environmental requirements for growth. Suspicion of infection relies on travel to or residence in recognized endemic regions. This report describes infection with histoplasmosis in two indoor cats from central California, an area not considered to be endemic for the disease. Systemic mycotic infections should be considered as differential diagnoses in any cat with compatible clinical signs, regardless of travel history or residence, especially if the cat is presented within a recognized endemic region. 相似文献
125.
126.
The present study was undertaken to compare the effect of salinomycin and Bacillus subtilis on growth performance, serum antibody levels against Clostridium spp. and Eimeria spp., and cytokine mRNA expression levels in broiler chickens raised in the used litter. Broiler chickens fed a diet containing salinomycin showed lower (P < 0.05) body weights compared with the control diet-fed counterparts. Serum nitric oxide levels were significantly (P < 0.05) elevated in chickens fed the B. subtilis-enriched diet compared with those on either the salinomycin-fed or control diet-fed chickens. None of the dietary treatments affected (P > 0.05) serum antibody levels against Clostridium perfringens toxins. Both salinomycin and B. subtilis significantly lowered (P < 0.05) the serum levels of Eimeria-specific antibodies compared with the control group. Salinomycin, but not B. subtilis, significantly modulated (P < 0.05) the expression of cytokines encoding interferon-γ (IFN-γ), interleukin10 (IL-10) and tumor necrosis factor superfamily 15 (TNFSF15) compared with the control group. In conclusion, dietary salinomycin and B. subtilis affected serum anticoccidial antibody and intestinal cytokine expression, but failed to improve growth performance in broiler chickens. Further study is warranted to investigate the mode of action of salinomycin on host immune response and growth performance in broiler chickens. 相似文献
127.
JoonHo Moon Ji-Yei Choi Jung-Taek Kang Sol Ji Park Su Jin Kim Goo Jang Byeong Chun Lee 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(1):167-171
The level of P4 at the time of embryo transfer (ET) is important. P4 concentrations and numbers of corpora lutea for 126 recipients were evaluated. Nuclear transfer embryos were transferred into 126 surrogates. 11 maintained their pregnancy until full-term delivery, 17 miscarried, and implantation failed in 98 animals. P4 levels in the full-term group were significantly different from those of the pigs that aborted or in which implantation failed (p < 0.05). However, the numbers of corpora lutea were not significantly different. These findings indicate that the concentration of progesterone can be an important factor for successful ET in pigs. 相似文献
128.
Chang‐Hoon Kwon Seung‐ Jae Han Sung‐Jae Kim Byung‐Chul Park Insurk Jang Jeong‐Hee Han 《Animal Science Journal》2014,85(8):805-813
This study was aimed to evaluate the effect of dietary supplementation of lipid‐encapsulated (coated) zinc oxide ZnO on post‐weaning diarrhea (colibacillosis) in weaned piglets challenged with enterotoxigenic Escherichia coli (ETEC). Thirty‐two 35‐day‐old weaned piglets were orally challenged with 3 × 1010 colony forming units of ETEC K88 while eight piglets received no challenge (control). Each eight challenged piglets received a diet containing 100 ppm ZnO (low ZnO), 2500 ppm ZnO (high ZnO) or 100 ppm of lipid (10%)‐coated ZnO (coated ZnO) for 7 days; control pigs received the low ZnO diet. Daily gain, goblet cell density in the villi of the duodenum, jejunum and ileum, and villus height in the jejunum and ileum, which decreased due to the challenge, were equally greater in the coated ZnO and high ZnO groups versus low ZnO group. Fecal consistency score, serum interleukin‐8 concentration, subjective score of fecal E. coli shedding, and digesta pH in the stomach, jejunum and ileum, which increased due to the challenge, were equally low in the coated ZnO and high ZnO groups versus low ZnO. Results suggest that a low level of coated ZnO might well substitute for a pharmacological level of native ZnO in dietary supplementation to alleviate colibacillosis of weaned piglets. 相似文献
129.
By trapping molecules between two gold electrodes with a temperature difference across them, the junction Seebeck coefficients of 1,4-benzenedithiol (BDT), 4,4'-dibenzenedithiol, and 4,4'-tribenzenedithiol in contact with gold were measured at room temperature to be +8.7 +/- 2.1 microvolts per kelvin (muV/K), +12.9 +/- 2.2 muV/K, and +14.2 +/- 3.2 muV/K, respectively (where the error is the full width half maximum of the statistical distributions). The positive sign unambiguously indicates p-type (hole) conduction in these heterojunctions, whereas the Au Fermi level position for Au-BDT-Au junctions was identified to be 1.2 eV above the highest occupied molecular orbital level of BDT. The ability to study thermoelectricity in molecular junctions provides the opportunity to address these fundamental unanswered questions about their electronic structure and to begin exploring molecular thermoelectric energy conversion. 相似文献
130.
Jang J Ferguson DG Vakaryuk V Budakian R Chung SB Goldbart PM Maeno Y 《Science (New York, N.Y.)》2011,331(6014):186-188
Spin-triplet superfluids can support exotic objects, such as half-quantum vortices characterized by the nontrivial winding of the spin structure. We present cantilever magnetometry measurements performed on mesoscopic samples of Sr(2)RuO(4), a spin-triplet superconductor. With micrometer-sized annular-shaped samples, we observed transitions between integer fluxoid states as well as a regime characterized by "half-integer transitions"--steps in the magnetization with half the height of the ones we observed between integer fluxoid states. These half-height steps are consistent with the existence of half-quantum vortices in superconducting Sr(2)RuO(4). 相似文献