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Blair O Wolf - One of the best experts on this subject based on the ideXlab platform.

  • avian thermoregulation in the heat resting metabolism evaporative cooling and heat tolerance in sonoran desert Doves and quail
    The Journal of Experimental Biology, 2015
    Co-Authors: Eric Krabbe Smith, Jacqueline Oneill, Alexander R Gerson, Blair O Wolf
    Abstract:

    ABSTRACT Birds in subtropical deserts face significant thermoregulatory challenges because environmental temperatures regularly exceed avian body temperature. To understand the differing susceptibility of desert birds to increasing temperatures, we examined thermoregulatory performance and estimated heat tolerance limits (HTLs) for three Sonoran Desert nesting bird species – Gambel9s quail, mourning Doves and white-winged Doves. Using flow-through respirometry we measured daytime resting metabolism, evaporative water loss and real-time body temperature at air temperatures (Tair) from 30°C to 66°C. We found marked increases in resting metabolism at the upper critical temperature (Tuc), which was significantly lower in the quail (Tair=41.1°C) than in both dove species (Tair=45.9–46.5°C). Gambel9s quail maintained low resting metabolic rates and low rates of evaporative water loss at their Tuc (0.71 W and 1.20 g H2O h−1, respectively), but were more sensitive to increasing air temperature, reaching their HTL at Tair of 52°C. Mourning Doves and white-winged Doves maintained low resting metabolic rates (0.66 and 0.94 W), but higher rates of evaporative water loss (1.91 and 2.99 g H2O h−1) at their Tuc and reached their HTL at Tair of 58–60°C. Mass-specific evaporative water loss in white-winged Doves (147 g) and mourning Doves (104 g) was 45% and 30% greater, respectively, than the rate observed in Gambel9s quail (161 g) at Tair of 48°C. Higher rates of evaporation and higher Tuc made the Doves exceptionally heat tolerant, allowing them to maintain body temperatures at least 14°C below air temperatures as high as 60°C (140°F).

  • partitioning of evaporative water loss in white winged Doves plasticity in response to short term thermal acclimation
    The Journal of Experimental Biology, 2004
    Co-Authors: Andrew E Mckechnie, Blair O Wolf
    Abstract:

    We investigated changes in the relative contributions of respiratory evaporative water loss (REWL) and cutaneous evaporative water loss (CEWL) to total evaporative water loss (TEWL) in response to short-term thermal acclimation in western white-winged Doves Zenaida asiatica mearnsii . We measured REWL, CEWL, oxygen consumption and carbon dioxide production in a partitioned chamber using flow-through respirometry. In Doves housed for 2-4 weeks in a room heated to ca . 43°C during the day, TEWL increased from 5.5±1.3 mg g-1 h-1 at an air temperature ( T a) of 35°C to 19.3±2.5 mg g-1 h-1 at T a=45°C. In Doves housed at room temperature for the same period, TEWL increased from 4.6±1.1 mg g-1 h-1 at T a=35°C to 16.1±4.6 mg g-1 h-1 at T a=45°C. The CEWL of heat-acclimated Doves increased from 3.6±1.2 mg g-1 h-1 (64% of TEWL) at 35°C to 15.0±2.1 mg g-1 h-1 (78% of TEWL) at T a=45°C. Cool-acclimated Doves exhibited more modest increases in CEWL, from 2.7±0.7 mg g-1 h-1 at T a=35°C to 7.8±3.4 mg g-1 h-1 at T a=45°C, with the contribution of CEWL to TEWL averaging 53% over this T a range. Cool-acclimated Doves became mildly hyperthermic (body temperature T b=42.9±0.4°C) and expended 35% more energy relative to heat-acclimated Doves ( T b=41.9±0.6°C) at T a=45°C, even though TEWL in the two groups was similar. In each of the two groups, metabolic rate did not vary with T a, and averaged 7.1±0.5 mW g-1 in cool-acclimated Doves and 6.3±0.8 mW g-1 in heat-acclimated Doves. The differences in TEWL partitioning we observed between the two experimental groups resulted from a consistently lower skin water vapour diffusion resistance ( r v) in the heat-acclimated Doves. At T a=45°C, r v in the cool-acclimated Doves was 120±81 s cm-1, whereas r v in the heat-acclimated Doves was 38±8 s cm-1. Our data reveal that in Z. a. mearnsii , TEWL partitioning varies in response to short-term thermal acclimation.

  • partitioning of evaporative water loss in white winged Doves plasticity in response to short term thermal acclimation
    The Journal of Experimental Biology, 2004
    Co-Authors: Andrew E Mckechnie, Blair O Wolf
    Abstract:

    We investigated changes in the relative contributions of respiratory evaporative water loss (REWL) and cutaneous evaporative water loss (CEWL) to total evaporative water loss (TEWL) in response to short-term thermal acclimation in western white-winged Doves Zenaida asiatica mearnsii. We measured REWL, CEWL, oxygen consumption and carbon dioxide production in a partitioned chamber using flow-through respirometry. In Doves housed for 2-4 weeks in a room heated to ca. 43 degrees C during the day, TEWL increased from 5.5+/-1.3 mg g(-1) h(-1) at an air temperature (T(a)) of 35 degrees C to 19.3+/-2.5 mg g(-1) h(-1) at T(a)=45 degrees C. In Doves housed at room temperature for the same period, TEWL increased from 4.6+/-1.1 mg g(-1) h(-1) at T(a)=35 degrees C to 16.1+/-4.6 mg g(-1) h(-1) at T(a)=45 degrees C. The CEWL of heat-acclimated Doves increased from 3.6+/-1.2 mg g(-1) h(-1) (64% of TEWL) at 35 degrees C to 15.0+/-2.1 mg g(-1) h(-1) (78% of TEWL) at T(a)=45 degrees C. Cool-acclimated Doves exhibited more modest increases in CEWL, from 2.7+/-0.7 mg g(-1) h(-1) at T(a)=35 degrees C to 7.8+/-3.4 mg g(-1) h(-1) at T(a)=45 degrees C, with the contribution of CEWL to TEWL averaging 53% over this T(a) range. Cool-acclimated Doves became mildly hyperthermic (body temperature T(b)=42.9+/-0.4 degrees C) and expended 35% more energy relative to heat-acclimated Doves (T(b)=41.9+/-0.6 degrees C) at T(a)=45 degrees C, even though TEWL in the two groups was similar. In each of the two groups, metabolic rate did not vary with T(a), and averaged 7.1+/-0.5 mW g(-1) in cool-acclimated Doves and 6.3+/-0.8 mW g(-1) in heat-acclimated Doves. The differences in TEWL partitioning we observed between the two experimental groups resulted from a consistently lower skin water vapour diffusion resistance (r(v)) in the heat-acclimated Doves. At T(a)=45 degrees C, r(v) in the cool-acclimated Doves was 120+/-81 s cm(-1), whereas r(v) in the heat-acclimated Doves was 38+/-8 s cm(-1). Our data reveal that in Z. a. mearnsii, TEWL partitioning varies in response to short-term thermal acclimation.

  • use of saguaro fruit by white winged Doves isotopic evidence of a tight ecological association
    Oecologia, 2000
    Co-Authors: Blair O Wolf, Martinez C Del Rio
    Abstract:

    We report the use of stable isotope and crop content analyses to quantify the use of saguaro (Carnegiea gigantea) nectar and fruit by migratory desert white-winged Doves (Zenaida asiatica mearsnii). Saguaro resources had characteristically 13C-enriched CAM values (δ13C=–12.8±0.7‰ SD VPDB and –13.1±0.5‰ SD VPDB for nectar and fruit, respectively) relative to other food plants used by Doves (δ13CC3=–24.9±3.3‰ SD VPDB). The water contained in saguaro nectar and fruit was deuterium enriched (δD=19.6±2.0‰ SD VSMOW and 48.4±1.6‰ SD VSMOW for nectar and fruit, respectively) relative to other water sources (ranging from –41 to –19‰ VSMOW). During the fruiting season, there was a positive correlation between δ13C in dove liver tissues and percent of saguaro in crop contents. A two-point mixing model indicated that during the peak of saguaro fruit use, most of the carbon incorporated in dove tissues was from saguaro. Desert white-winged Doves appear to be saguaro specialists. Averaged over the period when Doves were resident, saguaro comprised about 60% of the total carbon incorporated into dove tissues. Tissue δ13C and δD of body water showed a significant positive correlation, indicating that Doves were using saguaro as a source of both nutrients and water. However, at the peak of saguaro utilization, the Doves’ body-water δD was more positive (by about 20‰) than saguaro fruit water. We hypothesize that this enrichment is due to fractionated evaporative water losses by Doves. Using dove carbon isotope data and a two end-point mixing model we estimate that, on average, Doves consume the equivalent of 128 saguaro fruits per season; each fruit contains on average 26.0±14.8 g SD of pulp (wet mass) of which 19.4 g is water. Stable isotopes have been used to produce qualitative re-constructions of animal diets. Our study shows that they can be used to provide quantitative estimates of the flow of nutrients from resources into consumers as well.

Andrew E Mckechnie - One of the best experts on this subject based on the ideXlab platform.

  • partitioning of evaporative water loss in white winged Doves plasticity in response to short term thermal acclimation
    The Journal of Experimental Biology, 2004
    Co-Authors: Andrew E Mckechnie, Blair O Wolf
    Abstract:

    We investigated changes in the relative contributions of respiratory evaporative water loss (REWL) and cutaneous evaporative water loss (CEWL) to total evaporative water loss (TEWL) in response to short-term thermal acclimation in western white-winged Doves Zenaida asiatica mearnsii . We measured REWL, CEWL, oxygen consumption and carbon dioxide production in a partitioned chamber using flow-through respirometry. In Doves housed for 2-4 weeks in a room heated to ca . 43°C during the day, TEWL increased from 5.5±1.3 mg g-1 h-1 at an air temperature ( T a) of 35°C to 19.3±2.5 mg g-1 h-1 at T a=45°C. In Doves housed at room temperature for the same period, TEWL increased from 4.6±1.1 mg g-1 h-1 at T a=35°C to 16.1±4.6 mg g-1 h-1 at T a=45°C. The CEWL of heat-acclimated Doves increased from 3.6±1.2 mg g-1 h-1 (64% of TEWL) at 35°C to 15.0±2.1 mg g-1 h-1 (78% of TEWL) at T a=45°C. Cool-acclimated Doves exhibited more modest increases in CEWL, from 2.7±0.7 mg g-1 h-1 at T a=35°C to 7.8±3.4 mg g-1 h-1 at T a=45°C, with the contribution of CEWL to TEWL averaging 53% over this T a range. Cool-acclimated Doves became mildly hyperthermic (body temperature T b=42.9±0.4°C) and expended 35% more energy relative to heat-acclimated Doves ( T b=41.9±0.6°C) at T a=45°C, even though TEWL in the two groups was similar. In each of the two groups, metabolic rate did not vary with T a, and averaged 7.1±0.5 mW g-1 in cool-acclimated Doves and 6.3±0.8 mW g-1 in heat-acclimated Doves. The differences in TEWL partitioning we observed between the two experimental groups resulted from a consistently lower skin water vapour diffusion resistance ( r v) in the heat-acclimated Doves. At T a=45°C, r v in the cool-acclimated Doves was 120±81 s cm-1, whereas r v in the heat-acclimated Doves was 38±8 s cm-1. Our data reveal that in Z. a. mearnsii , TEWL partitioning varies in response to short-term thermal acclimation.

  • partitioning of evaporative water loss in white winged Doves plasticity in response to short term thermal acclimation
    The Journal of Experimental Biology, 2004
    Co-Authors: Andrew E Mckechnie, Blair O Wolf
    Abstract:

    We investigated changes in the relative contributions of respiratory evaporative water loss (REWL) and cutaneous evaporative water loss (CEWL) to total evaporative water loss (TEWL) in response to short-term thermal acclimation in western white-winged Doves Zenaida asiatica mearnsii. We measured REWL, CEWL, oxygen consumption and carbon dioxide production in a partitioned chamber using flow-through respirometry. In Doves housed for 2-4 weeks in a room heated to ca. 43 degrees C during the day, TEWL increased from 5.5+/-1.3 mg g(-1) h(-1) at an air temperature (T(a)) of 35 degrees C to 19.3+/-2.5 mg g(-1) h(-1) at T(a)=45 degrees C. In Doves housed at room temperature for the same period, TEWL increased from 4.6+/-1.1 mg g(-1) h(-1) at T(a)=35 degrees C to 16.1+/-4.6 mg g(-1) h(-1) at T(a)=45 degrees C. The CEWL of heat-acclimated Doves increased from 3.6+/-1.2 mg g(-1) h(-1) (64% of TEWL) at 35 degrees C to 15.0+/-2.1 mg g(-1) h(-1) (78% of TEWL) at T(a)=45 degrees C. Cool-acclimated Doves exhibited more modest increases in CEWL, from 2.7+/-0.7 mg g(-1) h(-1) at T(a)=35 degrees C to 7.8+/-3.4 mg g(-1) h(-1) at T(a)=45 degrees C, with the contribution of CEWL to TEWL averaging 53% over this T(a) range. Cool-acclimated Doves became mildly hyperthermic (body temperature T(b)=42.9+/-0.4 degrees C) and expended 35% more energy relative to heat-acclimated Doves (T(b)=41.9+/-0.6 degrees C) at T(a)=45 degrees C, even though TEWL in the two groups was similar. In each of the two groups, metabolic rate did not vary with T(a), and averaged 7.1+/-0.5 mW g(-1) in cool-acclimated Doves and 6.3+/-0.8 mW g(-1) in heat-acclimated Doves. The differences in TEWL partitioning we observed between the two experimental groups resulted from a consistently lower skin water vapour diffusion resistance (r(v)) in the heat-acclimated Doves. At T(a)=45 degrees C, r(v) in the cool-acclimated Doves was 120+/-81 s cm(-1), whereas r(v) in the heat-acclimated Doves was 38+/-8 s cm(-1). Our data reveal that in Z. a. mearnsii, TEWL partitioning varies in response to short-term thermal acclimation.

Louis Lefebvre - One of the best experts on this subject based on the ideXlab platform.

  • A field test of behavioural flexibility in Zenaida Doves (Zenaida aurita).
    Behavioural Processes, 2010
    Co-Authors: Neeltje Janna Boogert, Karine Monceau, Louis Lefebvre
    Abstract:

    Animals' ability to adjust their behaviour when environmental conditions change can increase their likelihood of survival. Although such behavioural flexibility is regularly observed in the field, it has proven difficult to systematically quantify and predict inter-individual differences in free-living animals. We presented 24 Zenaida Doves (Zenaida aurita) on 12 territories with two learning tests in their natural habitat in Barbados. The dove pairs showed high site fidelity and territoriality, allowing us to test individuals repeatedly while accounting for the effects of territorial chases and pair bonds on our learning measures. We used a foraging apparatus that enabled Zenaida Doves to access seed, yet excluded other species, and measured Doves' performance on colour discrimination and reversal learning tests. We found that (1) Doves on all 12 territories passed the two tests; (2) mates within a pair were consistently solvers or scroungers; (3) sex, body condition and territorial chases did not consistently affect learning rates; (4) tameness was a significant negative predictor of learning to feed from the foraging apparatus and (5) scrounging within pairs seemed to facilitate learning. Our study presents a method to quantify intraspecific differences in behavioural flexibility in the field and relate these to individuals' physical and social traits.

  • mixed species aggregations in birds zenaida Doves zenaida aurita respond to the alarm calls of carib grackles quiscalus lugubris
    Animal Behaviour, 2005
    Co-Authors: Andrea S Griffin, Rahul Savani, Kristina Hausmanis, Louis Lefebvre
    Abstract:

    Aggregating with heterospecifics may be particularly beneficial for a species that is able to exploit the antipredator behaviour of another. Territorial zenaida Doves vigorously exclude conspecific intruders from their territory, but forage with, and acquire novel foraging techniques from, carib grackles. Given that Doves associate with no other conspecific than their mate and they have no vocal alarm signals of their own, they might benefit from attending to the conspicuous alarm calls of carib grackles. In the present study, we found that zenaida Doves suppressed foraging both in response to a model predator and in response to the sound of grackle alarm vocalizations. Although Doves' responses to the predator model also involved moving away from the immediate vicinity, their responses to grackle alarm vocalizations consisted of remaining alert and tail flicking. Together, these results strongly suggest that Doves attend to the antipredator behaviour of carib grackles. These findings extend earlier work demonstrating that Doves obtain foraging benefits from their association with grackles, to show that they may also obtain predator avoidance benefits.

  • ecological mechanisms of a resource polymorphism in zenaida Doves of barbados
    Ecology, 2005
    Co-Authors: Daniel Sol, Michael Elie, Marianne Marcoux, Eva Chrostovsky, Celine Porcher, Louis Lefebvre
    Abstract:

    Despite the important place of resource polymorphisms in ecological and evolutionary theories, the reason why a group of individuals sharing a common environment should diverge in the use of the resources remains poorly known. Given the existence of distinct open niches and the relaxation of interspecific competition, niche theory suggests two possible mechanisms: resource competition between conspecifics and trade-offs in resource use efficiency. We investigated the importance of these explanations in a foraging polymorphism recently developed by Zenaida Doves (Zenaida aurita) on the West Indian island of Barbados. In this polymorphism, individuals either aggressively defend feeding territories from conspecifics or feed in large unaggressive groups with conspecifics. Com- bining field observations and a cage experiment, we found no evidence that the polymor- phism is primarily driven by age- or sex-related differences, or that it results from mor- phological feeding specializations or dietary preferences. Instead, our results support the hypothesis that individual specializations arise from contest competition. In the study area, competition for territories was intense, with very little undefended space left between territories and owners frequently involved in territorial contests. Replacement of territory holders from year to year was low compared to the number of potential recruits, implying that many Doves were incapable of securing a territory. Approximately half the Doves at territorial sites did not hold a territory but wandered between them as floaters. Compared with territory holders, floaters were smaller and had shorter wings, traits that in this species mediate territory defense. Yet floaters did not differ from group feeding Doves on these morphological traits. This suggests that group feeders are floaters that shift to an alternative resource. The new resource appears to be suboptimal, as indicated by the fact that group feeders were in worse body condition than Doves from the territorial sites. Taken together, our results suggest that the resource polymorphism in Zenaida Doves is primarily driven by competition for territories, which forces less competitive individuals to use alternative, subobtimal resources.

Zheng Xing - One of the best experts on this subject based on the ideXlab platform.

  • susceptibility of spotted Doves streptopelia chinensis to experimental infection with the severe fever with thrombocytopenia syndrome phlebovirus
    PLOS Neglected Tropical Diseases, 2019
    Co-Authors: Changjun Bao, Chengfeng Gao, Nan Zhang, Carol J Cardona, Zheng Xing, Huo Xiang
    Abstract:

    Background Severe fever with thrombocytopenia syndrome virus (SFTSV), an emerging human pathogen naturally transmitted by ticks, has spread widely since it was first detected in 2010. Although SFTSV-specific antibodies have been detected in wild birds, these natural reservoir and amplifying hosts for the virus have not been well studied. Methodology/Principle findings Here we report an experimental infection of spotted Doves (Streptopelia chinensis) with two strains of SFTSV, JS2010-14, a Chinese lineage strain, and JS2014-16, a Japanese lineage strain, which represent the main viral genotypes currently circulating in East Asia. In these studies, we have determined that spotted Doves are susceptible to SFTSV and the severity of the viremia is dose-dependent. When challenged with 107 and 105 PFU, all Doves developed viremia which peaked 3–5 days post infection (dpi). Only a subset (25–62.5%) of the birds developed viremia when challenged at 103 PFU. Virulence of SFTSV in spotted Doves was strain dependent. Infection with 107 PFU of strain JS2014-16 resulted in 12.5% mortality over 6.8 days and mean peak viremia titers of 106.9 PFU/mL in experimentally inoculated birds. All Doves inoculated with 107 PFU of the JS2010-14 strain survived infection with relatively lower mean viremia titers (105.6 PFU/mL at peak) over 6.1 days. Conclusions/Significance Our results suggest that spotted Doves, one of the most abundant bird species in China, could be a competent amplifying host for SFTSV and play an important role in its ecology. Between the two SFTSV strains, the strain of the Japanese lineage caused mortality, higher viremia titers in infected birds over a longer time period than did the Chinese strain. Our observations shed light on the ecology of SFTSV, which could benefit the implementation of surveillance and control programs.

  • susceptibility of spotted Doves streptopelia chinensis to experimental infection with the sfts phlebovirus
    bioRxiv, 2018
    Co-Authors: Changjun Bao, Chengfeng Gao, Nan Zhang, Xiang Huo, Carol J Cardona, Zheng Xing
    Abstract:

    Abstract Background: Severe fever with thrombocytopenia syndrome virus (SFTSV), an emerging human pathogen naturally transmitted by ticks, has spread widely during the last few years. Although SFTSV has been detected in wild birds, the natural reservoir and amplifying hosts for the virus have not been well-studied. Methodology/Principle Findings: Here we report an experimental infection of spotted Doves (Streptopelia chinensis) with two strains of SFTSV, JS2010-14 (hereafter JS2010), a Chinese lineage strain and JS2014-16 (JS2014) from a Japanese lineage, which represent the main viral genotypes currently circulating in East Asia. We determined that spotted Doves were susceptible to SFTSV and the severity of the viremia was dose-dependent. When challenged with 107 and 105 PFU, all Doves developed viremia which peaked 3-5 days post-infection (dpi). A subset (25-62.5%) of the birds challenged at 103 PFU, developed viremia. Virulence of SFTSV in spotted Doves appeared to be strain-dependent. Infection with the strain of JS2014 led to a death rate of 12.5% and higher viremia titers in experimentally inoculated birds. The Doves inoculated with the JS2010 strain survived infection with relatively lower virus titers in the blood. Conclusions/Significance: Our results suggest that spotted Doves, one of the most abundant bird species in China, could be a competent amplifying host of SFTSV, the strain of the Japanese lineage in particular, with higher viremia titers and play an important role in the transmission of SFTSV. Our observations shed light on the ecology of SFTSV which could benefit the implementation of future surveillance and control programs.

Keith C Hamer - One of the best experts on this subject based on the ideXlab platform.

  • the protozoan parasite trichomonas gallinae causes adult and nestling mortality in a declining population of european turtle Doves streptopelia turtur
    Parasitology, 2015
    Co-Authors: Jennifer E Stockdale, Jenny C Dunn, Simon J Goodman, Antony J Morris, Danae K Sheehan, Philip V Grice, Keith C Hamer
    Abstract:

    Studies incorporating the ecology of clinical and sub-clinical disease in wild populations of conservation concern are rare. Here we examine sub-clinical infection by Trichomonas gallinae in a declining population of free-living European Turtle Doves and suggest caseous lesions cause mortality in adults and nestlings through subsequent starvation and/or suffocation. We found a 100% infection rate by T. gallinae in adult and nestling Turtle Doves (n = 25) and observed clinical signs in three adults and four nestlings (28%). Adults with clinical signs displayed no differences in any skeletal measures of size but had a mean 3·7% reduction in wing length, with no overlap compared to those without clinical signs. We also identified T. gallinae as the suggested cause of mortality in one Red-legged Partridge although disease presentation was different. A minimum of four strains of T. gallinae, characterized at the ITS/5·8S/ITS2 ribosomal region, were isolated from Turtle Doves. However, all birds with clinical signs (Turtle Doves and the Red-legged Partridge) carried a single strain of T. gallinae, suggesting that parasite spill over between Columbidae and Galliformes is a possibility that should be further investigated. Overall, we highlight the importance of monitoring populations for sub-clinical infection rather than just clinical disease.