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Claudia TRANQUILLO Lucas Armand WAUTERS Francesca SANTICCHIA Damiano PREATONI Adriano MARTINOLI 《Integrative zoology》2023,18(4):746-761
Habitats are characterized by different local environmental conditions that influence both behavior and morphology of species, which can result in habitat-dependent phenotypic differences among animals living in heterogeneous environments. We studied 3 alpine populations of Eurasian red squirrels (Sciurus vulgaris), 1 living in a marginal high-elevation habitat at the edge of the species’ altitudinal distribution, and 2 occurring in higher-quality habitats. Here, we investigated whether squirrels living in the marginal area differed in 2 morphological parameters (body size and body mass) and/or in the expression of 4 personality traits estimated with an open field test and a mirror image stimulation test (activity, exploration, activity-exploration, and social tendency). Furthermore, we tested whether within-individual variance of the traits (behavioral plasticity) was higher in the edge habitat. Male squirrels in the edge habitat were smaller and weighed less than in the other study areas, while among females, size–habitat relationships were less marked. These sex-specific patterns were explained by a strong association between body mass and reproductive success in female squirrels. Squirrels in the marginal habitat were more active, explorative, and had a more social personality than in the other habitats. However, in contrast to our predictions, behavioral plasticity was smaller in the marginal habitat, but only for the trait exploration. Our results suggest that animals choose the habitat that best fits their personality, and that habitat-related differences in selective pressures may shape animals’ morphology. 相似文献
2.
Comparison of water status indicators for young peach trees 总被引：12，自引：1，他引：12
We measured a series of physiological and physical indicators and compared them to xylem sap flow, to identify the most sensitive and reliable plant water status indicator. In the growing season of 1998, 4-year-old peach trees (Prunus persica Batsch cv. 'Suncrest', grafted on 'GF 677' rootstock) were studied under two irrigation treatments, 25 l dayу and no irrigation, and during recovery. Trials were conducted near Pisa (Italy) in a peach orchard situated on a medium clay loam soil and equipped with a drip-irrigation system (four 4 l hу drippers per tree). Measurements of leaf water potential (ƒW), stem water potential (ƒS), and leaf temperature (Tl) were taken over 5 days (from dawn to sunset) and analyzed in conjunction with climatic data, sap flow (SF), trunk diameter fluctuation (TDF) and soil water content (SWC). Physiological indicators showed substantial differences in sensitivity. The first indication of changes in water status was the decrease of stem radial growth. TDF and SF revealed significant differences between the two irrigation treatments even in the absence of differences in pre-dawn leaf water potential (pdƒW), up until now widely accepted as the benchmark of water status indicators. Irrigated trees showed a typical trend in SF rate during the day, while in non-irrigated plants the maximum peak of transpiration was anticipated. Measurements of water potential showed ƒS to be a better indicator of tree water status than ƒW. Tl was found to have poor sensitivity. In conclusion, we found the sensitivity of the indicators from the most to the least was: TDF >SF rate >SF cumulated = pdƒW=ƒS>mdƒW>Tl. 相似文献
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Laura Marconato Carmit Chalfon Riccardo Finotello Gerry Polton Maria E. Vasconi Maurizio Annoni Damiano Stefanello Paola Mesto Ombretta Capitani Chiara Agnoli Maria Amati Silvia Sabattini 《Veterinary and comparative oncology》2019,17(4):537-544
Treatment options for dogs with metastatic (stage III) splenic hemangiosarcoma are limited. A doxorubicin‐based chemotherapy regimen is commonly administered; however, there are no published data to support this practice. The aim of this study was to investigate the impact of maximum‐tolerated‐dose chemotherapy (MTD), metronomic chemotherapy (MC) and no adjuvant treatment on outcome in dogs with stage III splenic hemangiosarcoma undergoing splenectomy. Medical records of dogs with stage III splenic hemangiosarcoma that underwent splenectomy followed by MTD chemotherapy, MC or no adjuvant treatment were retrieved. Time to progression (TTP), survival time (ST) and toxicity were evaluated. One hundred three dogs were identified: 23 received adjuvant MTD, 38 MC and 42 were not medically treated. Overall median TTP and ST were 50 (95% confidence interval [CI], 39‐61) and 55 days (95% CI, 43‐66), respectively. Dogs treated with adjuvant MTD had a significantly longer TTP and ST compared with dogs receiving MC (median TTP, 134 vs 52 days, P = .025; median ST, 140 vs 58 days, P = .023, respectively). Dogs treated by splenectomy only had the shortest median TTP (28 days) and ST (40 days). However, treatment‐related adverse events (AEs) were significantly more frequent in the MTD group (P = .017). The outcome for dogs with metastatic splenic hemangiosarcoma is poor. While MTD showed greater efficacy compared to MC, toxicity was higher in this group. Treatment‐related AEs need to be carefully balanced against this modest survival prolongation when offering adjuvant MTD to dogs with advanced stage hemangiosarcoma. 相似文献
4.
Genotyping,pedigree reconstruction and endocrinological characterization of Acipenser naccarii (Bonaparte, 1836) using microsatellite markers and plasma steroid levels 
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下载免费PDF全文 Ilaria Guarniero Laura Stancampiano Alessia Cariani Nadia Govoni Albamaria Parmeggiani Damiano Barboni Oliviero Mordenti 《Aquaculture Research》2017,48(11):5550-5560
This study aimed to set up a method for the long‐term management of Adriatic sturgeon, through the analysis of sex steroids and the genetic profiling of individuals in order to maximize the already reduced genetic variability of this species. Ten A. naccarii adults (nine of captive origin, one captured in the Ticino river and then moved into captivity) and eight subadults located in a semi‐natural land‐locked pond in Abbiategrasso (Milan, Italy) were analysed. Plasma testosterone differed significantly in the eight analysed subadults allowing their differentiation into two groups: the first group with an average testosterone concentration of 5.42 ± 1.31 ng/ml (probably female) and the second group with an average of 423.14 ± 75.97 ng/ml (probably male), as subsequently confirmed by artificial stripping. The plasma testosterone level was also significantly different between adult males and females (371.37 ± 43.58 vs. 95.34 ± 51.10 ng/ml), while the E2 levels showed no significant differences. Animals were genotyped on the basis of 10 microsatellite loci and their parental relationships were defined: four adults, two females and two males, generated the eight subadults. On the basis of pedigree analyses and genetic distances, 15 unrelated couples were identified for the future breeding seasons. Finally, the adult female captured in the Ticino River showed an interesting genetic profile, widely different from all of the other 17 specimens analysed, and represents a valuable source of genetic diversity. 相似文献
5.
Relationship between level of forage intake,blood flow and oxygen consumption by splanchnic tissues of sheep fed a tropical grass forage 下载免费PDF全文
下载免费PDF全文 F. Hentz G. V. Kozloski D. Zeni M. V. Brun S. Stefanello 《Journal of animal physiology and animal nutrition》2017,101(1):121-126
Four Polwarth castrated male sheep (42 ± 4.4 kg live weight (LW) surgically implanted with chronic indwelling catheters into the mesenteric, portal and hepatic veins, housed in metabolism cages and offered Cynodon sp. hay at rates (g of dry matter (DM)/kg LW) of 7, 14, 21 or ad libitum, were used in a 4 × 4 Latin square experiment to evaluate the effect of the level of forage intake on blood flow and oxygen consumption by the portal‐drained viscera (PDV), liver and total splanchnic tissues (ST). The portal blood flow and the oxygen consumption by PDV linearly increased at increased organic matter (OM) intake. No effect of level of OM intake was obtained for the hepatic artery blood flow and oxygen consumption by liver. As a consequence, the level of OM intake only tended to directly affect hepatic blood flow and oxygen consumption by total ST. Oxygen consumption was linearly and positively related to blood flow across PDV, liver and total ST. The heat production by PDV and total ST, as proportion of metabolizable energy (ME) intake, decreased curvilinearly at increased ME intake. In conclusion, the oxygen consumption by PDV, but not by liver, was directly related to the level of forage intake by sheep. Moreover, when ingested at levels below maintenance, most of ME was spent as heat produced by ST. 相似文献
6.
Ciarcia R. Damiano S. Panico C. Scanni R. Fiorito F. Florio S. Welch J. W. 《Veterinary research communications》2010,34(1):83-86
An elevation in angiotensin II (Ang II) levels is a common occurrence in spontaneously hypertensive rats (SHRs). Infusions of Ang II and a high salt diet increase the activity of NADPH oxidase that stimulates superoxide anion (O−2) generation and increases the expression of certain subunits of NADPH oxidase. Apocynin, an NADPH oxidase inhibitor with antihypertensive effects, is able to inhibit the release of superoxide anion by inhibiting NADPH oxidase activity and blocking the migration of p47 phox to the mitochondrial membrane. The aim of our study was to evaluate the antihypertensive effects of apocynin in SHRs and Wistar rats (WKYs) using a micropuncture technique. After microperfusion of both the proximal and distal tubules, we found that SHRs treated with apocynin showed a decrease in the free-flow collection of the proximal tubule (PT), which was not affected in WKYs. Moreover, significant differences were not demonstrated in the distal tubule (DT), probably due a mechanism of compensation that occurs in the loop of Henle. In conclusion, it is possible that the mechanisms of reabsorption in the PT are controlled by the interactions of O−2 and nitric oxide (NO). These data could suggest a higher activity of NADPH oxidase and increase in reactive oxygen species (ROS) production in the PT during hypertension.
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Stefanello D Valenti P Zini E Comazzi S Gelain ME Roccabianca P Avallone G Caniatti M Marconato L 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2011,25(1):90-93
Background: Splenic marginal zone lymphomas (MZL) in dogs arise from the marginal zone of B‐cell follicles and can progress slowly. Objectives: To describe clinical features, treatment, and outcome of dogs with splenic MZL. Animals: Five dogs with naturally occurring MZL. Methods: Clinical, laboratory, and follow‐up data were retrospectively reviewed. Diagnosis was based on clinical, histopathological, and immunophenotypic features. Results: All dogs had stage IV disease; among them, 2 were symptomatic (substage “b”) because of splenic rupture. Four dogs underwent splenectomy and adjuvant doxorubicin, and 1 dog underwent surgery only. Three out of the 4 dogs treated with surgery and chemotherapy died of causes unrelated to lymphoma, after 760, 939, and 1,825 days, whereas the remaining dog was alive and in complete remission after 445 days. The dog not receiving any adjuvant treatment had recurrence of the tumor after 180 days. Conclusions and Clinical Importance: Splenic MZL appears indolent and can benefit from splenectomy, with or without systemic chemotherapy. 相似文献
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Carotenuto AM Ravasio G Fonda D Stefanello D 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(5):515-518
We describe a case of proximal mandibular nerve block with ropivacaine, using electrolocation, for perioperative pain management in a geriatric dog undergoing rostral mandibulectomy. The patient did not require intraoperative analgesia or analgesic supplementation for 8 h after the end of the surgery. 相似文献
10.
L. Marconato U. Bonfanti D. Stefanello M. R. Lorenzo G. Romanelli S. Comazzi E. Zini 《Veterinary and comparative oncology》2008,6(2):80-89
Cytosine arabinoside (ara‐C) is a component of many protocols for the treatment of acute leukaemia and non‐Hodgkin lymphomas in humans. The aim of the study was to prospectively evaluate the efficacy of ara‐C in a myeloablative regimen in a cohort of canine lymphomas with bone marrow involvement. Seventeen dogs were enrolled. Eight were treated with a VCAA‐based protocol (Group 1) and nine with the same regimen added with ara‐C (Group 2). Ara‐C was administered on a 5‐day schedule as an i.v. continuous infusion at the dose of 150 mg m?2 per day for five consecutive days. During treatment complete remission (CR) was achieved in two dogs in Group 1 and in eight dogs in Group 2. CR rate was significantly higher in Group 2 (P < 0.01). Median survival was 72.5 days (range 6–174) in Group 1 and 243 days (range 73–635) in Group 2. Survival was significantly longer in Group 2 (P < 0.001). Both protocols were well tolerated, with a low incidence of adverse events. Ara‐C added to a VCAA‐based protocol appears to be safe and beneficial in dogs with stage V lymphoma. Incorporation of the nucleoside analogue might be crucial for the development of future therapeutic strategies in dogs. 相似文献