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  • ? The effect of climatic variables (temperature and precipitation) on radial growth of the Mediterranean Maritime pine (Pinus pinaster Ait.) was studied using dendrochronological techniques in the Iberian Peninsula.
  • ? Ten tree-ring width chronologies, along the central distribution area of the species, were built. Chronology variability was analysed using Principal Component Analysis (PCA) for the period 1952–2005.
  • ? The first principal component (PC1) explained 56% of tree-growth variability. Tree-growth association with climate was analysed at regional and local scales using correlation coefficient and bootstrapped response functions.
  • ? Radial growth at both scales was positively correlated with rainfall during and prior to the growing season at all sites, and with summer rainfall before the growing season at five sites. Mean temperature effect changed according to the sampling site, from non-significant at the highest sites to significant (positive relationship in winter) at the lowest sites. Growth season temperature also had a negative effect.
  • ? The Kalman filter was applied to estimate changing association between growth and climate over-time. Results suggested a change in association, initiated in the 80s, from non-significant to significant (*p < 0.05) at six of the sampling sites.
  • ? Pinus pinaster is an accurate species for analysing tree-growth association with climate and for studying plant behaviour under global change conditions.
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    23.
    Ferrets are considered a popular small mammal pet, and like other companion animals they are reported to suffer from diseases affecting the neuromuscular system. There currently is a lack of comprehensive electrodiagnostic study regarding the appendicular nerves of ferrets. In this research investigation, 25 domestic ferrets were used for electromyography and motor nerve conduction studies of the tibial, fibular, ulnar, and radial nerves, including H reflexes of the tibial and ulnar nerves, as well as sensory conduction of the fibular nerve. Mean and standard deviations for motor and sensory nerve studies were established. The hypothesis that weight would be correlated with all distal and proximal compound muscle action potential latencies was tested and confirmed for the tibial, fibular, and radial nerves but not the ulnar nerve.  相似文献   
    24.
    To date, limited information is available on the ability of 'Hobi'-like pestiviruses (putative bovine viral diarrhoea 3) to infect and cause disease in animal species traditionally affected by pestiviruses. In order to obtain new insights into host range and pathogenic potential of this atypical pestivirus, BVDV-seronegative calves (n=5), lambs (n=5) and piglets (n=5) were experimentally infected with the European 'Hobi'-like strain Italy-1/10-1, whereas two animals per species served as uninfected controls. Appearance of clinical signs, leukopenia, viremia, viral shedding and seroconversion were monitored for 28 days post-infection. Calves and lambs were successfully infected, displaying respiratory signs (nasal discharge), moderate hyperthermia and leukopenia, viremia and viral shedding through the nasal and faecal routes. Antibody responses were observed in both animal species by ELISA and virus neutralisation assays. In contrast, inoculated piglets did not display any clinical signs nor leukopenia and viral RNA was not detected in any biological samples. Nevertheless, the presence of detectable antibodies by virus neutralisation accounted for a successful, albeit limited infection of these animals.  相似文献   
    25.
    Three immunoserological tests (IST) used for the detection of porcine trichinellosis, immunofluorescence (IF), enzyme-inmunoanalysis (EIA), and Western blot (WB), were compared. Three groups of animals were analyzed: Group 1, animals naturally infected with parasite burdens (PB) of <1 muscle larvae (ML)/g (n = 18); Group 2, animals naturally infected with PB of ≥2 ML/g (n = 23); Group 3, animals raised and home-slaughtered on farms in Argentina (n = 59). Animals from Groups 1 and 2 were identified in outbreaks and were analyzed by individual artificial digestion (AD) of ≥30 g of muscle. Animals in Group 3 were subjected to AD of 5 g of muscle.The detection percentages in sera of swine with the lower PB were 100% for IF, 72% for EIA, and 50% for WB. Eighty-three percent of the animals were serologically positive by two or three techniques. In pigs with the higher PB, the detection percentage was similar for IF and EIA (100% vs. 91%, respectively), and was lower for the WB (61%). Ninety-six percent of the animals were serologically positive by two or three techniques. Group 3 animals had similar detection percentages for the three techniques (IF, 30%; EIA, 29%; WB, 42%). Twenty-five percent of the animals were serologically positive by two or three techniques. Two animals were positive by AD with PB of 0.33 and 2.4 ML/g, and were positive for IF and WB, or IF, EIA, and WB. Results indicate that the sensitivity of each technique depends on the PB, and always ranked in sensitivity as IF > EIA > WB. For the lower PB, the decrease in the sensitivity is more pronounced for the EIA. Although the WB has a low sensitivity, the detection of the specific bands for Trichinella spiralis makes it a useful confirmatory tool. Considering that more than 83% of the parasitologically positive animals had 2 or 3 positive serological results using the techniques tested here, for the diagnosis of porcine trichinellosis, pigs positive by two of these serological techniques must be regarded as truly infected pigs.  相似文献   
    26.
    The front cover image is based on the Research Artice Effects of exogenous methyl jasmonate and salicylic acid on rice resistance to Oebalus pugnax by Thais F Stella de Freitas et al., DOI: 10.1002/ps.5174 . Image Credit: Thais Fernanda Stella de Freitas, Federal University of Rio Grande do Sul.

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    This report aims to describe the first case of muscular and collagenous choristoma in a dog. A 10-yr-old female mixed-breed dog presented with lateral recumbence, vocalization, positional vertical nystagmus, divergent strabismus, anisocoria, and status epilepticus. The clinical condition evolved to stupor and ultimately, death. Necropsy revealed a white mass causing an irregular increase in the volume of the cerebellar vermis. In histological analysis, a well circumscribed, unencapsulated mass was observed in the cerebellum, consisting of fibers of striated skeletal muscle and collagen fibers, mostly mineralized. Based on the histopathological and histochemical findings, a diagnosis of muscular and collagenous cerebellar choristoma was made.  相似文献   
    29.
    Canine visceral leishmaniasis poses important concerns for public health and veterinary medicine in many areas of the world. Resistance to it seems to be associated with cellular specific immune responses of the so-called Th1 type. Interleukin-12 (IL-12) is one of the most potent inducers of Th1 type of immune responses to co-administered antigens. Herein, the cloning of canine IL-12, as a single-chain fusion protein (sccaIL-12), and its expression in biologically active form in COS-7 cells is reported. Supernatants from these cells stimulated the expression of comparable amounts of interferon gamma mRNA in peripheral blood mononuclear cells from dogs with natural visceral leishmaniasis. In addition, after stimulation with sccaIL-12, there was no difference between interferon gamma mRNA expressions in peripheral blood mononuclear cells of dogs with visceral leishmaniasis and from normal healthy control animals.  相似文献   
    30.
    Hemoplasmas are ubiquitous pleomorphic and epicellular bacteria detected in erythrocytes in several species. In Brazil, studies on hemoplasmas have not included information on occurrence, clinical signs, and risk factors in dogs. This paper investigates the occurrence of hemoplasmas in dogs, focusing on risk factors and clinical status. Conventional PCR for the four types of canine hemoplasmas was performed in 331 blood samples collected from dogs clinically treated at a teaching veterinary hospital. Of all samples, 17/331 (5.1%) were positive for Mycoplasma haemocanis and 6/331 (1.8%) were positive for a ‘Candidatus Mycoplasma haemominutum-like’ organism. Risk factors included the presence of vectors, old age, dog bite wounds, and neoplastic diseases. In the multivariate analysis, a 4.40 odds ratio in dogs with vector-borne diseases indicated risk for hemoplasmosis. There was correlation between hemoplasma infection and neoplastic disease, suggesting that neoplastic conditions are a risk factor for hemoplasma infection in dogs.  相似文献   
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