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141.
Giuseppe Sarli Federico Morandi Serena Panarese Barbara Bacci Domenico Ferrara Carlo Bianco Laura Fusaro Maria Laura Bacci Giovanna Galeati Michele Dottori Paolo Bonilauri Davide Lelli Giorgio Leotti Thais Vila Francois Joisel Gordon Allan Cinzia Benazzi Fabio Ostanello 《Acta veterinaria Scandinavica》2012,54(1):51
Background
Since 1999, field evidence of transplacental infection by porcine circovirus type 2 (PCV2) and reproductive failure has been reported in pigs. The objective of this study was to evaluate the clinical and pathological consequences of PCV2 infection in conventional PCV2-seropositive gilts by insemination with PCV2b-spiked semen.Results
Six PCV2 seropositive gilts were inseminated with PCV2b-supplemented semen (infected) and three animals with semen and cell culture medium (controls). Only three out of the six infected animals were pregnant by ultrasonography on day 29 after insemination, while two out of the three controls were pregnant. One control gilt aborted on day 23 after insemination but not due to PVC2. Viraemia was demonstrated in four out of six infected and in one control gilt that became infected with PCV2a. Anti-PCV2 antibody titres showed dynamic variations in the infected group throughout the study. Among infected gilts, the animal with the lowest anti-PCV2 titre (1/100) at the beginning of the experiment and another that reached a similar low value during the experiment showed evident seroconversion over time and had also PCV2 positive foetuses. One placenta displayed mild focal necrosis of the chorionic epithelium positively stained by immunohistochemistry for PCV2 antigen.Conclusions
PCV2-seropositive gilts can be infected with PCV2 after intrauterine exposure and low maternal antibody titre may increase the probability of a foetal infection. 相似文献142.
Angelo?Garibaldi Giovanna?Gilardi Maria?Lodovica?GullinoEmail author 《Phytoparasitica》2004,32(1):61-65
Twenty-seven seed samples belonging to the lettuce cultivars most frequently grown in Lombardy (northwestern Italy), in an
area severely affected by Fusarium wilt of lettuce, were assayed for the presence ofFusarium oxysporum on a Fusarium-selective medium. Isolations were carried out on subsamples of seeds (500 to 1500) belonging to the same seed
lots used for sowing, and either unwashed or disinfected in 1% sodium hypochloride. The pathogenicity of the isolates ofF. oxysporum obtained was tested in four trials carried out on lettuce cultivars of the butterhead type, very susceptible to Fusarium
wilt. Nine of the 27 samples of seeds obtained from commercial seed lots used for sowing in fields affected by Fusarium wilt
were contaminated byF. oxysporum. Among the 16 isolates ofF. oxysporum obtained, only one was isolated from disinfected seeds. Three of the isolates were pathogenic on the tested cultivars of
lettuce, exhibiting a level of pathogenicity similar to that of the isolates ofF. oxysporum f.sp.lactucae obtained from infected wilted plants in Italy, USA and Taiwan, used as comparison. The results obtained indicate that lettuce
seeds are a potential source of inoculum for Fusarium wilt of lettuce. The possibility of isolatingF. oxysporum f.sp.lactucae, although from a low percent of seeds, supports the hypothesis that the rapid spread of Fusarium wilt of lettuce observed
recently in Italy is due to the use of infected propagation material. Measures for prevention and control of the disease are
discussed.
http://www.phytoparasitica.org posting Dec. 16, 2003. 相似文献
143.
Galeati G Forni M Spinaci M Zannoni A Govoni N Ribeiro LA Seren E Tamanini C 《Domestic animal endocrinology》2005,28(3):272-284
This study was designed to verify whether fasting influences vascular endothelial growth factor (VEGF) production and VEGF, VEGF receptor-2 (VEGFR-2) as well as endothelin (ET) system members (endothelin converting enzyme-1, ECE-1; ET-1; endothelin receptor type A, ET-A) mRNA expression in pig corpora lutea; furthermore, we wanted to assess whether fasting affects steroidogenesis in luteal cells. Eight prepubertal gilts were induced to ovulate and were randomly assigned to two groups: (A) n = 4, normally fed; and (B) n = 4, fasted for 72 h starting 3 days after ovulation. At the end of fasting, ovaries were removed from all the animals and corpora lutea (CLs) were collected. VEGF and steroid levels in luteal tissue were determined by ELISA and RIA, respectively; VEGF, VEGFR-2, ET-1, ET-A and ECE-1 mRNAs expression was measured by real-time PCR. VEGF protein levels were similar in the two groups, while all steroid (progesterone, testosterone, estradiol 17beta) concentrations were significantly (P < 0.001) higher in CLs collected from fasted animals compared with those from normally fed gilts. VEGF, VEGFR-2, ET-1 and ECE-1 (but not ET-A) mRNA expression was significantly lower (P < 0.05) in fasted versus normally fed animals. The overall conclusion is that all the parameters studied are affected by feed restriction, but the mechanisms activated at luteal level are possibly not fully adequate to compensate for nutrient shortage. 相似文献
144.
Mario Santoro Giovanna Hernández Magaly Caballero 《Journal of zoo and wildlife medicine》2006,37(4):549-552
Bacteriological examination of 70 nesting green turtles (Chelonia mydas) from Tortuguero National Park, Costa Rica was performed to investigate nasal and cloacal aerobic bacteria. A total of 325 bacterial isolates were obtained, including 10 Gram-negative and three Gram-positive genera. Two hundred thirty-nine were Gram-negative and 86 were Gram-positive isolates. Klebsiella pneumoniae was the most common microbe identified in turtle samples: 27/70 (38.5%) in cloacal, and 33/70 (47.1%) in nasal samples. The Enterobacteriaceae family, including Enterobacter agglomerans, E. cloacae, Escherichia coli, Klebsiella oxytoca, K. pneumoniae, and Serratia marcescens, was the largest Gram-negative group of bacteria recovered and comprised 127 of 239 (53.1%) of the Gram-negative isolates. Staphylococcus species was the largest Gram-positive bacteria group, including S. aureus, S. cromogenes, S. epidermis, and S. intermedius, and made up 63 of 86 (73.2%) of the Gram-positive isolates recovered. The results of this study demonstrate that the aerobic bacterial flora of nesting green turtles at Tortuguero National Park is composed of a very wide spectrum of bacteria, including several potential pathogens. 相似文献
145.
Accotto GP Nervo G Acciarri N Tavella L Vecchiati M Schiavi M Mason G Vaira AM 《Phytopathology》2005,95(7):800-807
ABSTRACT Tomato hybrids obtained from homozygous progeny of line 30-4, engineered for Tomato spotted wilt virus (TSWV) resistance, were tested under field conditions in two locations with their corresponding nontransgenic hybrids. No transgenic hybrid became infected, but 33 to 50% of plants of each nontransgenic hybrid became infected with a severe reduction of marketable fruit production. The transgenic hybrids conformed to the standard agronomic characteristics of the corresponding nontransgenic ones. Fruit were collected from the nontransgenic plots included in the experimental field and from border rows, and seed were used to estimate the flow of the transgene via pollen. No transgene flow was detected in the protected crops; however, in the open field experiment, 0.32% of tomato seedlings were found to contain the genetic modification. Immunity to TSWV infection in 30-4 hybrids was confirmed in laboratory conditions using mechanical inoculation and grafting. Thrips inoculation in leaf discs of line 30-4 demonstrated that TSWV replication was inhibited at the primary infection site but not in leaf discs of a commercial hybrid containing the naturally occurring resistance gene Sw-5. Due to the high economic value of tomato crops worldwide and the importance of TSWV, the engineered resistance described here is of practical value for breeding into cultivars of commercial interest, because it could be combined with naturally occurring resistance, thus greatly reducing the ability of the virus to develop resistance-breaking strains. 相似文献
146.
Santiago Bismarck Moreira da Silva Fabiano Ferreira Silva Robério Rodrigues Costa Evely Giovanna Leite Porto Junior Antonio Ferraz Costa Edvaldo Nascimento de Souza Dicastro Dias 《Tropical animal health and production》2019,51(3):599-604
Tropical Animal Health and Production - The aim of the study was to evaluate the effect of different forage sources in diets for feedlot dairy cows and their implications on production,... 相似文献
147.
Giovanna Faria Moraes Luíza Rodrigues Alves Abreu Fabio Luiz Buranelo Toral Isabel Cristina Ferreira Henrique Torres Ventura Jos Aurlio Garcia Bergmann Idalmo Garcia Pereira 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(6):464-473
The objectives were to conduct a genetic evaluation of residual feed intake (RFI) and residual feed intake adjusted for fat (RFIFat) and to analyse the effect of selection for these traits on growth, carcass and reproductive traits. Data from 945 Nellore bulls in seven feed efficiency tests in a feedlot were analysed. Genetic evaluation was performed using an animal model in which the feed efficiency test and age of the animal at the beginning of the test were considered as a systematic effect. Direct additive genetic and residual effects were considered as random effects. Correlations and genetic gains were estimated by two‐trait analysis between feed efficiency measures (RFI and RFIFat) and other traits. Feed conversion showed low heritability (0.06), but dry matter intake (DMI), average daily gain, RFI, RFIFat, metabolic body weight and scrotal circumference measured at 450 days of age (SC450) showed moderate to high heritability (0.49, 0.28, 0.33, 0.36, 0.38 and 0.80, respectively). Similarly, ribeye area, backfat thickness, rump cap fat thickness, marbling score and subcutaneous fat thickness also had high heritability values (0.46, 0.37, 0.57, 0.51 and 0.47, respectively). Genetic correlations between RFI and SC450 were null, and between RFIFat and SC450 were strongly positive. Genetic and phenotypic correlations of RFI and RFIFat with carcass traits were not different from zero, as correlated responses for carcass traits were also not different from zero. The Nellore selection for feed efficiency by RFI or RFIFat allows the recognition of feed efficient animals, with DMI reduction and without significant changes in growth and carcass traits. However, because of the observed results between RFIFat and SC450, selection of animals should be analysed with caution and a preselection for reproductive traits is necessary to avoid reproductive impairments in the herd. 相似文献
148.
Fabio Leonardi Giovanna Lucrezia Costa Claudia Dina Interlandi Jessica Rosa Andrea Ghidelli Marcello Musicò 《Veterinary anaesthesia and analgesia》2019,46(1):79-83
Objective
To evaluate the anaesthetic effects of three different alfaxalone doses to induce anaesthesia in goldfish.Study design
Prospective, randomized, clinical study.Animals
Thirty goldfish undergoing skin scraping, gill examination and stool collection.Methods
Each fish was transferred to an individual 4 L induction tank and randomly allocated into one of three groups (n = 10), in which alfaxalone was administered at concentrations of 6, 7 or 9 mg L–1. The depth of anaesthesia was evaluated by approach reaction, equilibrium, opercular movement and reaction to tactile stimuli. Sedation, light anaesthesia, surgical anaesthesia and recovery times were recorded. Data were analyzed with analysis of variance. A p value <0.05 was considered significant.Results
Surgical anaesthesia was achieved in all fish. Goldfish induced with alfaxalone 7 and 9 mg L–1 showed a mild excitement phase. Time to sedation of the 6 mg L–1 dose (5.89 ± 0.40 minutes) was significantly longer compared to the 7 mg L–1 (3.97 ± 0.40 minutes) and 9 mg L–1 doses (3.94 ± 0.40 minutes). Times to light anaesthesia and surgical anaesthesia of the 9 mg L–1 dose (7.65 ± 1.04 and 9.60 ± 1.84 minutes, respectively) were significantly faster compared with those of the 6 mg L–1 dose (13.79 ± 1.04 and 19.75 ± 1.84 minutes, respectively) and the 7 mg L–1 dose (13.55 ± 1.04 and 21.24 ± 1.84 minutes, respectively). No significant differences were recorded in recovery time. Cessation of opercular movement was recorded in two fish induced with 7 mg L–1 and in two induced with 9 mg L–1. No mortality occurred.Conclusions
and clinical relevance Alfaxalone is a reliable agent for immersion anaesthesia in goldfish. Immersion in water containing 6 mg alfaxalone L–1 provided smooth induction of anaesthesia, and no obvious side effects were encountered. Higher doses shortened induction time and caused respiratory depression and excitatory movements. 相似文献149.
Although the central nervous system is unable to undergo spontaneous repair and is hostile to the integration of exogenously delivered cells, various examples of adult structural plasticity have been shown to occur. It is now widely accepted that endogenous proliferative activity leading to the production of new neurons exists, at least within two restricted brain sites: the hippocampal dentate gyrus and the forebrain subventricular zone. A substantial insight into spontaneous neurogenesis within these allocortical regions in rodents has been obtained, but less is known regarding its occurrence in other mammalian brain regions. In this review, differences in the structural and temporal characteristics of protracted neurogenesis in mammals will be considered. Attention will be focused on the rabbit cerebrum and cerebellum, where unexpected features of structural plasticity have been found to occur despite the relative closeness of the Orders Lagomorpha and Rodentia. 相似文献
150.