Comparing the behavioural thermoregulation response to heat stress by Atlantic salmon parr (Salmo salar) in two rivers     

Emily Corey  Tommi Linnansaari  Stephen J. Dugdale  Normand Bergeron  Jean-François Gendron  Michel Lapointe  Richard A. Cunjak 《Ecology of Freshwater Fish》2020,29(1):50-62

Climate change is expected to increase the frequency and magnitude of extreme thermal events in rivers. The Little Southwest Miramichi River (LSWM) and the Ouelle River (OR) are two Atlantic salmon (Salmo salar) rivers located in eastern Canada, where in recent years, water temperatures have exceeded known thermal limits (~23°C). Once temperature surpasses this threshold, juvenile salmon exploit thermal heterogeneity to behaviourally thermoregulate, forming aggregations in coolwater refuges. This study aimed to determine whether the behavioural thermoregulation response is universal across rivers, arising from common thermal cues. We detailed the temperature and discharge patterns of two geographically distinct rivers from 2010 to 2012 and compared these with aggregation onset temperature. PIT telemetry and snorkelling were used to confirm the presence of aggregations. Mean daily maximum temperature in 2010 was significantly greater in the OR versus the LSWM (p = 0.005), but not in other years (p = 0.090–0.353). Aggregations occurred on 14 and 9 occasions in the OR and LSWM respectively. Temperature at onset of aggregation was significantly greater in the OR (T_onset = 28.3°C) than in the LSWM (T_onset = 27.3°C; p = 0.049). Logistic regression models varied by river and were able to predict the probability of aggregation based on the preceding number of hours >23°C (R² = 0.61 & 0.65; P₅₀ = 27.4°C & 28.9°C; in the OR and LSWM respectively). These results imply the preceding local thermal regime may influence behaviour and indicate a degree of phenotypic plasticity, illustrating a need for localised management strategies.  相似文献   

Antibody to bluetongue virus in cattle in Ecuador     

W. A. Lopez  P. Nicoletti  E. P. J. Gibbs 《Tropical animal health and production》1985,17(2):82-82

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Distribution of lesions in the lungs of aborted bovine fetuses          下载免费PDF全文

Lopez A  Pérez A  Angulo G 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(6):519-521

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Acquired resistance triggered by elicitins in tobacco and other plants   总被引：17，自引：0，他引：17  

Philippe Bonnet  Eva Bourdon  Michel Ponchet  Jean -Pierre Blein  Pierre Ricci 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(2):181-192

Elicitins are a family of proteins excreted byPhytophthora spp. They exhibit high sequence homology but large net charge differences. They induce necrosis in tobacco plants which then become resistant to the tobacco pathogenPhytophthora parasitica var.nicotianae. In stem-treated plants, resistance was not restricted to the site of elicitin application, but could be demonstrated by petiole inoculation at all levels on the stem. Resistance was already maximum after two days and lasted for at least two weeks. It was effective not only towardsP. p. var.nicotianae infection, but also against the unrelated pathogenSclerotinia sclerotiorum. In contrast to dichloroisonicotinic acid, an artificial inducer of systemic acquired resistance, which was increasingly effective with doses ranging from 0.25 to 5mole per plant, the basic elicitin cryptogein exhibited a threshold effect, inducing near total resistance and extensive leaf necrosis above 0.1 nmole per plant. Between 1 and 5 nmole, acidic elicitins (capsicein and parasiticein) protected tobacco plants with hardly any necrotic symptom. Elicitins exhibited similar effects in various tobacco cultivars andNicotiana species, although with quantitative differences, but induced neither necrosis nor protection in other SolanaceÆ (tomato, petunia and pepper). Among 24 additional species tested belonging to 18 botanical families, only some BrassicaceÆ, noticeably rape, exhibited symptoms in response to elicitins, in a cultivar-specific manner. Elicitins appear to be natural specific triggers for systemic acquired resistance and provide a tool for unraveling the mechanisms leading to its establishment.Abbreviations AR acquired resistance - HR hypersensitive response - INA 2,6-dichloroisonicotinic acid - Ppn Phytophthora parasitica var.nicotianae - SAR systemic acquired resistance  相似文献   

What Is Your Diagnosis?     

Desnoyers M  St-Germain L 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1994,23(3):89-90

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What Is Your Diagnosis?     

Nuñez-Ochoa L  Desnoyers M  Lecuyer M 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1993,22(4):122-123

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Heinz body anemia in a dog following possible naphthalene ingestion     

Desnoyers M  Hébert P 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1995,24(4):124-125

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Morphological and Physiological Responses of Plantain (Plantago lanceolata) and Chicory (Cichorium intybus) to Water Stress and Defoliation Frequency          下载免费PDF全文

L. M. Cranston  P. R. Kenyon  S. T. Morris  N. Lopez‐Villalobos  P. D. Kemp 《Journal of Agronomy and Crop Science》2016,202(1):13-24

Plants are often subjected to periods of water stress. There are little data examining the effect of water stress on the forage species Plantago lanceolata and Cichorium intybus. In two pot experiments with P. lanceolata and C. intybus, morphological responses under optimum, dry, and very‐dry water treatments with weekly, fortnightly and 3‐weekly defoliation intervals and physiological responses under optimum and very‐dry water treatments were measured. A third experiment compared the rooting depths of P. lanceolata and C. intybus under field conditions. These findings suggest that both P. lanceolata and C. intybus can survive and continue to grow under water stress conditions with the main differences between the two species being attributable to morphological characteristics (root mass, taproot diameter and shoot mass fraction) rather than differences at a physiological level. Overall, the results suggest plantain may be more productive under moderate drought due to its greater shoot mass fraction, whereas chicory may be more productive and persistent under severe drought due to its greater root mass, taproot diameter and root depth under field conditions.  相似文献   

Incisional complications after skin closure with n‐butyl cyanoacrylate or stainless‐steel skin staples in horses undergoing colic surgery     

Javier Martinez‐Lopez  James A. Brown  Stephen R. Werre 《Veterinary surgery : VS》2021,50(1):186-195

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Production,chemical composition,and fatty acid profile of milk from buffaloes fed with cupuaçu (Theobroma grandiflorum) cake and murumuru (Astrocaryum murumuru) cake in the Eastern Amazon     

André Guimarães Maciel e Silva  Suely Cristina Gomes de Lima  Pedro Danilo de Oliveira  Michel dos Santos Moraes  Célia Maria Costa Guimarães  Jamile Andréa Rodrigues da Silva  Alexandre Rossetto Garcia  Benjamim de Souza Nahúm  Lilaine de Sousa Neres  Gerlane Nunes Noronha  José de Brito Lourenço Júnior 《Animal Science Journal》2021,92(1):e13576

The objective was to evaluate the effect of concentrate supplementation using by-products of the Amazonian industry on milk production, milk composition, and milk fatty acid profile of dairy buffaloes. Twelve lactating buffaloes (544.5 ± 35.6 kg, 6.4 ± 2.2 years old, 59 ± 6 days in milk) were allotted in a pasture of Mombaça grass and managed under rotational grazing (4 days occupancy/28 days rest). A 3 × 3 Latin square was adopted, and each animal alternately received three supplementary treatments based on corn bran + soybean meal or cupuaçu cake or murumuru cake for 21 days per treatment. Murumuru cake increased the levels of lauric acid and myristic acid in the milk (p < 0.05). Murumuru cake reduced the unsaturated fatty acid contents in the milk compared with animals fed control diet or cupuaçu cake (24.27% vs. 25.24% vs. 25.08%). The n-6/n-3 ratio was 2.6, 1.97, and 2.0 in the control, cupuaçu, and murumuru groups, respectively. Based on this parameter, cakes made from cupuaçu as well as murumuru could be considered to be adequate for inclusion in dairy water buffalo feed. However, the murumuru cake addition requires some caution because its use induces the secretion of higher levels of lauric and myristic fatty acids that are related to human cardiovascular disease.  相似文献