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61.
Sera were collected from 490 dogs from north-west Italy. One hundred and eighty-eight dogs were urban, while 302 dogs were rural. Among the latter, 190 were shepherd dogs and 112 were cattle farm dogs. Sera were tested for the presence of antibodies against Neospora caninum using the Neospora agglutination test. Seroprevalence at 1/40, 1/80, 1/160 dilution titres was significantly higher in rural (36.4%, 19.5%, 9.9% respectively) than in urban dogs (20.2%, 10.6%, 4.8% respectively). Seroprevalence did not differ significantly in males and females. In shepherd dogs, prevalence increased according to dogs' age, thus suggesting a post-natal exposure by horizontal transmission. The observed higher seroprevalence in rural dogs suggests the importance of lifestyle and alimentary habits (i.e. aborted foetuses, placentas and small mammals) in the acquisition of N. caninum infection. Our results confirm that dogs are exposed to N. caninum and play an important role in the epidemiology of N. caninum.  相似文献   
62.
The aim of this study was to evaluate the performances and the flesh quality of Pagellus bogaraveo fed with diets containing rice protein concentrate [RPC, 70% crude protein (CP) and 10% ether extract]. Three isoproteic and isoenergetic (CP 47%, 22 MJ/kg DM) diets were formulated with an increasing level of RPC: 0%, 20% and 35%. The fish (mean weight 75 g) from the Messina Straits were randomly distributed in 12 tanks (3 diets x 4 replications, 10 fish/tank). The daily ratio (1.5% of the fish biomass) was updated every 15 days. Biomass gain showed an opposite trend to the RPC diet inclusion. No differences appeared in the somatic indexes. Differences appeared between fatty acid profiles of the dorsal muscle. Fatty acid of series n-6 increased and fatty acid of series n-3 decreased in fillets of fish fed with increasing levels of RPC. The inclusion of RPC in the diets, as a partial replacement of fish meal (20%), is possible without affecting the growth performance and fillet quality.  相似文献   
63.
The study of lipids and fatty acids (FAs) has been used in the assessment of egg quality because their composition can influence the fertilization rate, hatching, survival and growth of marine fish larvae. For these reasons, the lipid content (TL) and fatty acid composition of common sole (Solea solea) eggs were measured and correlated to egg and larval viability parameters throughout an entire reproductive season. Seventeen batches of fertile eggs obtained from natural spawning of captive breeders were characterized for the TL, FA profile, hatching rate (HR) and survival rate of larvae (SR) at 0–6 days post‐hatching (dph). The egg FA composition reflected the composition of the feed supplied to the broodstock during summer and autumn (before and during vitellogenesis) rather than that supplied during the spawning season. In general, the egg FA profile showed minimal differences among the early‐, mid‐ and late‐spawning periods (possibly due to the change of the diet and/or water temperature) indicating that it is possible to obtain a similar egg quality in terms of egg FA profile over 2 months of spawning. Saturated FAs and monounsaturated FAs (MUFA) were positively correlated with HR, while TL, 22 : 6n‐3 (DHA), 20 : 4n‐6 (ARA), polyunsaturated FAs of the (n‐3) series (n‐3 PUFA) and polyunsaturated FAs of the (n‐6) series were negatively correlated (p  0.05). MUFA, 20 : 5n‐3 (EPA), n‐6/n‐3 were positively correlated with SR, while DHA, n‐3 PUFA, DHA/EPA were negatively correlated (p  0.05). In conclusion, the feed supplied before and during vitellogenesis has a major role in determining the egg FA profile in common sole. The relationships found between TL and FAs with egg and larval viability parameters differ from many other farmed marine fish species, which may suggest the need for a specific broodstock feed for this species.  相似文献   
64.
Microvascular characteristics of the human interdental papilla   总被引:1,自引:0,他引:1  
The aim of this study was to observe the microcirculation characteristics of the human interdental papilla in healthy patients in vivo. Twenty healthy patients were examined. Capillaroscopy was used to investigate the characteristics of microcirculation of the human periodontal mucosa. Visibility, course, tortuosity, as well as the average caliber of the capillary loops and the number of visible capillary loops per square millimeter were evaluated for each patient. The investigation of gingival mucosa revealed capillary loops with a course both parallel and perpendicular to the surface. Our study has pointed out that capillaroscopy is a reliable method to study periodontal microcirculation in vivo. This method could be applied to the study of microcirculation in periodontal diseases. Future studies might evaluate whether microcirculation in that area is compromised or not during systemic pathologies involving peripheral microcirculation alterations.  相似文献   
65.
The use of adult stem cells in tissue regeneration appears to be a powerful research tool, due to the intrinsic characteristics of these cells, i.e., self-renewal and unlimited capacity for proliferation. In particular, mesenchymal stem cells (MSCs) obtained from bone marrow or peripheral blood can be easily isolated, cultivated, propagated and can be differentiated into several specialized cell types thanks to their plasticity. Among these cells, MSCs can evolve into cardiac cell lineages. Since heart damage leads to the irreversible loss of cardiac function, cell transplantation could be a potential therapy for heart injury. Our laboratory has focused on the purification and expansion of rat and sheep MSCs, their differentiation into cardiomyocytes and their characterisation. Numerous results indicate that MSCs could be promising for therapy, however we need to better understand the biology of stem cells to improve methods for delivery and/or pharmacological activation. These techniques can indeed track engrafted cells and systems to guarantee their safe use.  相似文献   
66.
In Denmark, the detection of multi-resistant Salmonella Typhimurium DT104 (MRDT104)-infected pig herds relies on the national Salmonella surveillance programme at the farm and slaughterhouse levels of production. With the surveillance sampling protocol and the diagnostic methods currently used, some herds might remain undetected. The number of undetected Danish pig herds infected with MRDT104 in the period 1 August 2001–31 July 2002 was estimated and compared with the number of culture-confirmed detected herds. A flow chart was constructed to illustrate where infected herds will go undetected in the surveillance system and Monte Carlo simulation was used to model the actual number of pig herds infected with MRDT1104. We estimated that 52 (90% CI [28, 178]) finisher herds were infected with MRDT104 compared to 23 (44%) detected. Among sow herds with production of weaners or growers, we estimated that 38 (90% CI [23, 74]) were infected with MRDT104 compared to 7 (18%) actually detected. Among breeder and multiplier herds, we estimated that five (90% CI [3, 8]) herds were infected with MRDT104 compared to three (60%) detected. In total, we estimated that 102 pig herds were infected with MRDT104 from 1 August 2001 till 31 July 2002 (90% CI [63, 228]). In comparison, 33 (32%) infected herds were detected in this period. The predicted proportion of undetected herds varied considerably with herd type. We infer that the proportion of detected MRDT104 infected herds depended on the intensity of the combined serological and bacteriological testing.  相似文献   
67.
68.
To support a voluntary disease control program, this study aimed to develop an integrated scoring system for the risk assessment of bovine viral diarrhoea virus (BVDV) infection in dairy herds in Northern Italy. Sixty-two dairy herds were classified according to their BVDV serological status. Farmers were interviewed using a questionnaire on potential BVDV risk factors. Scores were used to define risk levels for factors related to (1) BVDV introduction (through livestock trade, attendance of animals at shows/exhibitions and grazing common pasture), (2) within-herd spread of BVDV and (3) the results of initial serological testing. The calculated odds ratios were significant for all categories, except for livestock trade. The application of the screening test, the questionnaire and the related risk assessment showed this to be a practical approach to predicting BVDV herd status.  相似文献   
69.
The feasibility of using a SYBR Green-based real-time RT-PCR assay (SYBR Green ReTi RT-PCR) followed by melting curve analysis (MCA) for detecting and genotyping porcine reproductive and respiratory syndrome virus (PRRSV) was assessed. The SYBR Green ReTi RT-PCR and a previously reported two-step, non-nested RT-PCR assays were simultaneously tested on selected European (EU) and North American (US) PRRSV strains and isolates collected from diverse clinical, temporal, and geographical origins. The validation experiments showed that the optimised SYBR Green ReTi RT-PCR can sensitively and specifically detect PRRSV, consistently detecting as little as 0.03TCID(50)/sample of each virus genotype, with no type-bias and no amplification signal for other swine pathogens. After MCA, two well-differentiated melting temperature (T(m)) profiles for each virus genotype were obtained, as sequencing confirmed it. High repeatability was obtained for the T(m) values, with intra-run coefficients of variation (CoVs) of 0.25 and 0.32 and inter-run CoVs of 0.42 and 0.52 for EU and US genotypes, respectively. The sensitivity of the SYBR Green ReTi RT-PCR (100%) was higher than that of the RT-PCR (95.7%) when testing field isolates. This greater sensitivity of the SYBR Green ReTi RT-PCR was further confirmed by the detection of a higher proportion of PRRSV-positive diagnostic specimens (29.7%) than by the RT-PCR (28.5%). The SYBR Green ReTi RT-PCR test detected infection as early as 2 dpi in the sera of experimentally infected pigs regardless of virus genotype, and discriminated negative (non-inoculated), EU- and US-infected pigs. In conclusion, the reported SYBR Green ReTi RT-PCR assay coupled with MCA can detect and type PRRSV and may be useful as an alternative diagnostic assay in diverse PRRSV epidemiological circumstances.  相似文献   
70.
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