Effects of submergence on cardiac cycle and rate in aquatic and terrestrial birds

1961 ◽  
Vol 200 (4) ◽  
pp. 723-726 ◽  
Author(s):  
Charles F. Bond ◽  
Steven D. Douglas ◽  
Perry W. Gilbert
Keyword(s):  
Cardiac Cycle ◽  
Wild Birds ◽  
Aquatic Birds ◽  
Cardiac Rate ◽  
Vascular Control ◽  
Diving Ducks

Electrocardiograms were recorded for various aquatic and terrestrial birds with heads submerged and then returned to air. Instantaneous cardiac rates were calculated and P-R and Q-T intervals were measured at selected times. Bradycardia developed in all birds during submergence, but was most pronounced and longest sustained in aquatic birds. Upon emergence, aquatic birds and pigeons developed instantly a compensatory tachycardia; cardiac rate in the others gradually returned to the presubmergence level. In the first 15 seconds of submersion, P-R and Q-T intervals remained constant in all birds except pheasants, but in ducks undergoing prolonged submergence the Q-T interval increased significantly. This Q-T interval increase lagged approximately 60 seconds behind the onset of bradycardia. Diving ducks were like dabblers, supporting further the hypothesis that differences in their underwater activity cannot be explained by vascular differences. These observations on minimally restrained wild birds are consistent with the hypothesis of a differential vascular control of oxygen during diving. For underwater activity, aquatic birds utilize mechanisms appearing to some extent in all birds.

Note on host-parasite relationships observed in fluke infections of wild aquatic birds

Parasitology ◽  
1960 ◽  
Vol 50 (3-4) ◽  
pp. 323-327 ◽  
Author(s):  
B. P. Pande ◽  
S. S. Ahluwalia ◽  
J. S. Srivastava
Keyword(s):  
Wild Birds ◽  
Aquatic Species ◽  
Aquatic Birds ◽  
Representative Species ◽  
Helminthic Infections ◽  
House Crow ◽  
Host Parasite ◽  
Trematode Parasites

The last twenty-five years have witnessed an increasing output of significant work in this country on the trematode parasites of a number of wild birds, including aquatic species. These studies, which are mostly faunistic, and can be said to have commenced in 1926, when Bhalerao (1926) described from Burma (then a province of India) the flukes of the house crow, deal primarily with a large number of representative species of nearly twenty families of Digenea. Of these families, species assignable to the Clinostomidae Lühe, 1901, the Cyathocotylidae Poche, 1926, the Cyclocoelidae Kossack, 1911, the Diplostomidae Poirier, 1886, the Echinostomatidae Poche, 1926, the Notocotylidae Lühe, 1909, the Opisthorchiidae Braun, 1901, and the Strigeidae Railliet, 1919, were encountered in a survey conducted to assess the nature of helminthic infections in wild aquatic birds of the Mathura area.

scholarly journals Computational analysis of vertebrate myoglobins reveals aggregation resistance in aquatic birds and higher surface hydrophobicity in fish

2021 ◽  
Author(s):  
Syed M Rizvi ◽  
Wei Zheng ◽  
Chengxin Zhang ◽  
Yang Zhang
Keyword(s):  
Surface Hydrophobicity ◽  
Aquatic Birds ◽  
Tertiary Structures ◽  
Net Charge ◽  
Aggregation Propensity ◽  
Diving Ducks ◽  
Folding Algorithm ◽  
Vertebrate Muscle ◽  
Golden Eagles ◽  
General Association

Myoglobin is the major oxygen carrying protein in vertebrate muscle. Previous studies identified in secondarily aquatic mammalian lineages high myoglobin net charge, which serves to prevent aggregation at the extremely high intracellular myoglobin concentrations found in these species. However, it is unknown how aquatic birds that dive for extended durations prevent myoglobin aggregation at their high intracellular myoglobin concentrations. It is also unknown whether secondarily aquatic lineages reduced the surface hydrophobicity of their myoglobins to prevent aggregation. Here, we used a deep learning-predicted distance-based protein folding algorithm to model the tertiary structures of 302 vertebrate myoglobin orthologs and performed a comparative analysis of their predicted net charge and surface hydrophobicities. The results suggest that aquatic avian divers, such as penguins and diving ducks, evolved highly charged myoglobins to reduce aggregation propensity and allow greater storage of oxygen for extended underwater foraging. High myoglobin net charge was also identified in golden eagles, a species that routinely suffers high-altitude hypoxia. Although no general association was found between myoglobin surface hydrophobicity and intracellular concentration, comparison of predicted net charge and surface hydrophobicities revealed significant differences between major vertebrate classes; bird myoglobins are the most positively charge, reptile myoglobins are the most negatively charged, and the myoglobins of ray-finned fish (Actinopterygii) have higher surface hydrophobicity than those of lobe-finned fish (Sarcopterygii). Our findings indicate the convergent evolution of high myoglobin net charge in aquatic birds and mammals, and offer novel insights into the diversification of myoglobin among vertebrate clades.

Molecular Identification of Cryptosporidium spp. and Giardia spp. in Wild Birds in Southeastern Brazil

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
da Cunha MJR ◽  
◽  
Santos ALQ ◽  
Silva MBO ◽  
dos Santos MC ◽  
...  
Keyword(s):  
Nested Pcr ◽  
Epidemiological Studies ◽  
Enterocytozoon Bieneusi ◽  
Wild Birds ◽  
Southeastern Brazil ◽  
Pcr Analysis ◽  
Aquatic Birds ◽  
Free Living ◽  
Cryptosporidium Spp ◽  
The Impact

Introduction: The identification of Cryptosporidium spp., Giardia spp. and Enterocytozoon bieneusi in birds is relevant since these animals can act as disseminators of these parasites to humans through environmental contamination. The aim of this study was to determine the molecular occurrence of Cryptosporidium spp. and Giardia spp. in wild birds in southeastern Brazil and genetically characterize the isolates obtained. Methods: A total of 256 fecal samples were collected from 172 captive and 84 free-living wild birds. The DNA extracted was subjected to nested-PCR and semi-nested PCR analysis for amplification of fragments of the 18S rDNA and gdh genes of Cryptosporidium spp. and Giardia spp., respectively. Results: With respect to Cryptosporidium spp., the overall occurrence was 3.91%. Of samples from captive wild birds, six (3.49%) were positive: two waterfowl and four non-aquatic birds. Among the samples from free-living wild birds, four (4.76%) were positive, all non-aquatic birds. Regarding Giardia spp., the overall occurrence was 3.1%. Of samples from captive wild birds, four (2.32%) were positive, all waterfowl; of the samples from free-living wild birds, four (4.76%) were positive for the parasite, all non-aquatic birds. Conclusions: The presence of C. meleagridis and G. duodenalis assemblage B suggests that epidemiological studies involving wild birds and humans are needed to better understand the impact of avian cryptosporidiosis and giardiasis on avian health and their possible implications for public health.

scholarly journals Influenza surveillance in wild birds in Australia

2011 ◽  
Vol 32 (1) ◽  
pp. 48
Keyword(s):  
Avian Influenza ◽  
Wild Birds ◽  
Influenza Viruses ◽  
Influenza Surveillance ◽  
Aquatic Birds ◽  
Avian Influenza Viruses ◽  
Natural Reservoir

Wild aquatic birds are the natural reservoir for avian influenza viruses (AIVs)1. Increased surveillance has revealed that Australia has its own lineages of these AIVs.

Body mass, volume, and buoyancy of some aquatic birds, and their relation to locomotor strategies

1991 ◽  
Vol 69 (11) ◽  
pp. 2888-2892 ◽  
Author(s):  
James R. Lovvorn ◽  
David R. Jones
Keyword(s):  
Linear Regression ◽  
Body Mass ◽  
Aquatic Birds ◽  
Water Displacement ◽  
Sea Ducks ◽  
Diving Ducks ◽  
The Common ◽  
Mass Volume

Body mass, volume, and buoyancy of diving ducks, surface-feeding ducks, auklets, cormorants, and gulls were measured by means of water displacement. Relations of volume and buoyancy to body mass in surface-feeding ducks were linear and did not differ from those of diving ducks if scoters and eiders were excluded. These large-bodied sea ducks (scoters and eiders) had buoyancies 22–28% above values predicted by the common linear regression for surface-feeding ducks and smaller diving ducks. Thus, scoters and eiders have larger respiratory or plumage air volumes relative to body mass. Although relations of volume and buoyancy to body mass were similar among most ducks, volumes and buoyancies of gulls were much higher, and those of cormorants much lower, than those of ducks. Volumes and buoyancies of auklets were the same as those of ducks of similar mass. The significance to locomotion of the buoyancy of restrained birds depends on predive expiration and ptilosuppression, and reduced buoyancy from compression of air spaces at foraging depths typical for the species.

1306: Techniques of Vascular Control and their Effects on Vessel Length

2004 ◽  
Vol 171 (4S) ◽  
pp. 344-344
Author(s):  
Jonathan E. Bernie ◽  
Chandru P. Sundaram,
Keyword(s):  
Vascular Control ◽  
Vessel Length

Reduction of major amputations in the diabetic ischaemic foot: A strategy to "take control" with conservative care as well as revascularisation

VASA ◽  
2001 ◽  
Vol 30 (Supplement 58) ◽  
pp. 6-14 ◽  
Author(s):  
Edmonds ◽  
Foster
Keyword(s):  
Natural History ◽  
Treatment Plan ◽  
Staging System ◽  
Vascular Control ◽  
New Approach ◽  
Conservative Care ◽  
Arterial Bypass ◽  
Therapeutic Footwear ◽  
Frequent Problem

The diabetic ischaemic foot has become an increasingly frequent problem over the last decade. However, we report a new approach consisting of a basic classification, a simple staging system of the natural history and a treatment plan for each stage, within a multi-disciplinary framework. This approach of "taking control" consists of two parts: 1. long-term conservative care including debridement of ulcers (to obtain wound control), eradication of sepsis (micribiological control), and provision of therapeutic footwear (mechanical control), and 2. revascularisation by angioplasty and arterial bypass (vascular control). This approach has led to a 50% reduction in the rate of major amputations in patients attending with ischaemic ulceration and absent foot pulses from 1989 to 1999 (from 4.6% to 2.3% per year). Patients who underwent angioplasty increased from 6% to 13%. Arterial bypass similarly increased from 3% to 7% of cases. However, even with an increased rate of revascularisation, 80% of patients responded to conservative care alone. This,we conclude, is an essential part of the management of all patients with ischaemic feet.

The Bad Language of Wild Birds

1899 ◽  
Vol 47 (1209supp) ◽  
pp. 19389-19390
Author(s):  
Charles A. Witchell
Keyword(s):  
Wild Birds
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