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81.
Journal of Plant Diseases and Protection - In 2016, symptoms of stem canker with branches dieback were detected in several Cannabis sativa L. crops, located in the northeast part of Italy (Rovigo... 相似文献
82.
Overall development of a bioprocess for the outdoor production of Nannochloropsis gaditana for aquaculture 下载免费PDF全文
Karina Riveros Claudia Sepulveda Jazmín Bazaes Paola Marticorena Carlos Riquelme Gabriel Acién 《Aquaculture Research》2018,49(1):165-176
In this paper, a systematic methodology is shown for the scaling‐up of Nannochloropsis gaditana production for aquaculture uses. First, an adequate culture medium was developed, prepared using fertilizers instead of pure chemicals. Subsequently, the performance of N. gaditana was modelled as a function of average irradiance; this model being validated in continuous culture experiments. The model was used to determine the optimal dilution rate as well as the expected biomass concentration and productivity at optimal conditions. Finally, outdoor experiments were performed to confirm the model's validity and to determine optimal conditions at real production step. Biomass productivity values of up to 0.08 g L?1 day?1 were obtained at an optimal dilution rate of 0.25 per day in 0.2 m wide flat‐panel reactors using culture medium containing 0.4 g/L NO?3 and 0.034 g/L·PO4?3. Fish trials with Atlantic Salmon demonstrated that the inclusion of produced biomass into fed increase the final weight up to 5%, thus confirming the adequacy of the biomass produced for aquaculture uses. The growth model and the scaling‐up strategy proposed here are necessary to develop real industrial‐scale processes capable of supplying microalgal biomass to the aquaculture markets, which in turn require a guaranteed supply and quality of the raw materials provided. 相似文献
83.
Domitilla Pulcini Tommaso Russo Paola Reale Alexia Massa‐Gallucci Grace Brennan Stefano Cataudella 《Aquaculture Research》2014,45(3):397-409
Prolonged exposure to captive conditions has led to the development of a rainbow trout ‘farmed’ phenotype, which is different from that of wild trout. Selection for desirable productive traits in hatcheries has resulted in the development of some morphological traits that are maladaptive in nature. The recent development of organic aquaculture, guided by the well‐being of the fish, could potentially produce a new farmed phenotype that would be more adaptive in nature. In this study, rainbow trout reared in intensive and organic farms were compared by means of shape analysis, to detect patterns of shape variation associated with rearing environment. The results of this study highlight a significant effect of the rearing method on rainbow trout shape: organically reared trout showed a higher body profile, in particular in the head and trunk regions, shorter median fins and a deeper caudal peduncle. A combined effect of density and habitat complexity could have contributed to the observed shape differences: in organic rearing systems, lower densities and steady water could increase territoriality and aggressive interactions, promoting body designs more functional in rapid attacks and escapes. 相似文献
84.
85.
Gabriele Vaccari Gaia Scavia Marcello Sala Gianmario Cosseddu Barbara Chiappini Michela Conte Elena Esposito Raniero Lorenzetti Gabriella Perfetti Paola Marconi Francesco Scholl Katia Barbaro Antonino Bella Romolo Nonno Umberto Agrimi 《Veterinary research》2009,40(3)
The susceptibility of sheep to scrapie is under the control of the host’s prion protein (PrP) gene and is also influenced by the strain of the agent. PrP polymorphisms at codons 136 (A/V), 154 (R/H) and 171 (Q/R/H) are the main determinants of susceptibility/resistance of sheep to classical scrapie. They are combined in four main variants of the wild-type ARQ allele: VRQ, AHQ, ARH and ARR. Breeding programmes have been undertaken on this basis in the European Union and the USA to increase the frequency of the resistant ARR allele in sheep populations. Herein, we report the results of a multi-flock study showing the protective effect of polymorphisms other than those at codons 136, 154 and 171 in Sarda breed sheep. All ARQ/ARQ affected sheep (n = 154) and 378 negative ARQ/ARQ controls from four scrapie outbreaks were submitted to sequencing of the PrP gene. The distribution of variations other than those at the standard three codons, between scrapie cases and negative controls, was statistically different in all flocks. In particular, the AT137RQ and ARQK176 alleles showed a clear protective effect. This is the first study demonstrating a protective influence of alleles other than ARR under field conditions. If further investigations in other sheep breeds and with other scrapie sources confirm these findings, the availability of various protective alleles in breeding programmes of sheep for scrapie resistance could be useful in breeds with a low frequency of the ARR allele and would allow maintaining a wider variability of the PrP gene. 相似文献
86.
Dermatophytosis is a common zoonotic disease, and one of its clinical presentations in the dog is nodular dermatophytosis (kerion). Because the infection is located within the dermis, routine diagnostic tests such as a Wood's lamp examination, microscopic examination of hair shafts for fungal elements and fungal culture can yield negative results. In such cases, histopathological examination with routine and special stains (periodic acid-Schiff, Gomori methenamine silver) is required to confirm the diagnosis. Nodular dermatophytosis in 23 dogs of different breed, age and sex with single or multiple nodules is described. Twelve dogs had a single nodule, and 11 dogs showed multiple lesions. Wood's lamp examination was negative in all cases. Microscopic examination of plucked hairs showed arthrospores in 8 of 23 cases. Skin scrapings in mineral oil looking for arthrospores and/or hyphae were positive in 12 cases. Impression smears of exudates were diagnostic in 21 of 23 cases (91%), showing arthrospores within fragments of hair shafts or free among neutrophils and macrophages (pyogranulomatous inflammation). Histopathology was performed in two cases. Fungal culture was positive for Microsporum canis in 16 dogs and for Microsporum gypseum in one dog. In six cases, the causative agent was not identified by fungal culture. All dogs were treated with systemic antifungal therapy and in eight cases with concurrent antibiotic therapy. Nodular dermatophytosis resolved in all dogs with the prescribed treatments within 4 to 8 weeks. Transmission to people or other pets in the home was not found. 相似文献
87.
Bernardo Chessa Marco Pittau Maria Puricelli Rosanna Zobba Elisabetta Coradduzza Paola DallAra Sergio Rosati Giorgio Poli Alberto Alberti 《Research in veterinary science》2009,86(3):414-420
A DNA vaccine against contagious agalactia was developed for the first time, encoding the P48 of Mycoplasma agalactiae. Specific immune responses elicited in BALB/c mice were evaluated. Both total IgG and IgG1 were detected in mice vaccinated with pVAX1/P48. Proliferation of mononuclear cells of the spleen, levels of gamma interferon, interleukin-12, and interleukin-2 mRNAs were enhanced in immunized animals. Results indicate that pVAX1/P48 vaccination induced both Th1 and Th2 immune responses. Nucleic acid immunization could be a new strategy against M. agalactiae infections and may be potentially used to develop vaccines for other Mycoplasma diseases. 相似文献
88.
Ricardo Marcos Marta Santos Fernanda Malhão Rui Pereira Ana Cristina Fernandes Luís Montenegro Paola Roccabianca 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(2):201-205
Abstract: A 4‐year‐old, domestic shorthair, female spayed cat was presented for decreased appetite and depression. Severe pancytopenia with erythrocyte autoagglutination was found. The cat was seronegative for feline immunodeficiency and leukemia viruses. Immune‐mediated hemolytic anemia was suspected but no response to treatment with a blood transfusion, enrofloxacin, and prednisone was observed. Blood and bone marrow smears obtained 11 days later contained Leishmania amastigotes in the cytoplasm of neutrophils and macrophages, respectively. Serologic and PCR testing of peripheral blood confirmed infection with Leishmania infantum. Despite treatment, the cat worsened clinically and was euthanized. At necropsy, visceral dissemination of the parasite was confirmed. The findings in this case indicate that visceral leishmaniasis should be considered as a differential diagnoses in cats with pancytopenia in areas endemic for Leishmania. In addition, amastigotes may be observed in peripheral blood neutrophils. 相似文献
89.
Lecchi C Avallone G Giurovich M Roccabianca P Ceciliani F 《Veterinary journal (London, England : 1997)》2009,180(2):256-258
Combined quantitative (real-time) polymerase chain reaction and immunohistochemistry were used to evaluate the expression of the minor acute phase protein alpha 1-acid glycoprotein (AGP, orosomucoid) in bovine extrahepatic tissues. AGP was produced mainly in the salivary glands and spleen, whereas minor expression was detected in all other tissues sampled, including lung, lymph nodes, uterus, ovary, kidney and tongue. The findings were consistent with immunohistochemical results. In view of the immunomodulatory and direct antibacterial activity of AGP, its expression in the salivary glands may signal an involvement in the regulation of the local immunity, even in non-pathological conditions. 相似文献
90.
Maiolino P Restucci B Papparella S De Vico G 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(3):303-306
BACKGROUND: Telepathology is the process of diagnostic pathology performed on digital images viewed on a display screen rather than by conventional light microscopy with glass slides. At present, electronic mail (e-mail) attachment is the most common communication medium for telepathology, because it is relatively simple and incurs minimal cost. OBJECTIVE: Our objective was to test whether telediagnosis through Internet e-mail could be applied to veterinary diagnostic cytology. METHODS: Using 20 cytology cases, on which a consensus diagnosis was reached by 3 experienced pathologists, a total of 130 images were digitized and sent as e-mail attachments from the Unit of Anatomic Pathology of the Faculty of Veterinary Medicine of Naples to the Unit of Pathology of the Faculty of Veterinary Medicine of Messina, Italy. The images were reviewed at the Unit of Pathology of Messina, where the consulting pathologist formulated his diagnoses by visualizing the images on the monitor of a computer. The telediagnoses were compared with the consensus diagnoses and with the consulting pathologist's interpretation using conventional light microscopy at a later date. RESULTS: The median time to capture images was approximately 30 minutes for each case. The median time to make a telecytodiagnosis was a few seconds for each case. Overall, there was good agreement (85%) between the consensus diagnosis and the consultant's telediagnosis. In 100% of the cases there was agreement between the consulting pathologist's telediagnosis and conventional glass slide diagnosis. CONCLUSION: Telepathology by e-mail provides acceptable efficacy and a faster turnaround time than post and can be applied to veterinary diagnostic cytology. 相似文献