Environmental Influences on the Respiratory Physiology and Gut Chemistry of a Facultatively Air-breathing, Tropical Herbivorous Fish Hypostomus regani (Ihering, 1905)

2016 ◽  
pp. 191-218 ◽  
Author(s):  
Jay A. Nelson ◽  
Flavia Sant’Anna Rios ◽  
José Roberto Sanches ◽  
Marisa Narciso Fernandes ◽  
Francisco Tadeu Rantin
Keyword(s):  
Environmental Influences ◽  
Respiratory Physiology ◽  
Herbivorous Fish ◽  
Air Breathing

scholarly journals Atypical respiratory Physiology of a recent air‐breathing fish: Pangasius

2015 ◽  
Vol 29 (S1) ◽  
Author(s):  
Mark Bayley ◽  
My Phuong ◽  
Christian Damsgaard ◽  
Do Thi Thanh Huong ◽  
Tobias Wang
Keyword(s):  
Respiratory Physiology ◽  
Air Breathing

scholarly journals Evolutionary and cardio‐respiratory physiology of air‐breathing and amphibious fishes

2019 ◽  
Vol 228 (3) ◽  
Author(s):  
Christian Damsgaard ◽  
Vikram B. Baliga ◽  
Eric Bates ◽  
Warren Burggren ◽  
David J. McKenzie ◽  
...  
Keyword(s):  
Respiratory Physiology ◽  
Air Breathing ◽  
Amphibious Fishes

scholarly journals Respiratory Physiology of Intestinal Air Breathing in the Teleost Fish Misgurnus Anguillicaudatus

1987 ◽  
Vol 133 (1) ◽  
pp. 371-393 ◽  
Author(s):  
BRIAN R. McMAHON ◽  
WARREN W. BURGGREN
Keyword(s):  
Gas Exchange ◽  
Alimentary Canal ◽  
Co2 Exchange ◽  
Gas Diffusion ◽  
Respiratory Physiology ◽  
Misgurnus Anguillicaudatus ◽  
Air Breathing ◽  
Intestinal Gas ◽  
Partial Pressures ◽  
O2 Extraction

The Japanese weatherloaeh (Misgurnus anguillicaudatus Cantor) can exchange gases both with water, via gills and skin, and with air, via the posterior region of the alimentary canal (intestine). Air breathing occurs by unidirectional ventilation of the alimentary canal with air taken in at the mouth and simultaneous expulsion of intestinal gas from the vent. Although the weatherloaeh is not an obligate air-breather, aerial gas exchange normally occurs even at 10°C in air-saturated water. The alimentary canal was examined histologically to assess differences in capillary density and distribution and the diffusion distance for gases across those regions modified for aerial respiration. A respirometer system specifically designed for 2- to 3-g fish allowed continuous measurement of O2 and CO2 exchange via both aquatic and aerial routes at rest and at various ambient temperatures, and respiratory gas partial pressures. Air ventilation volumes, O2 and CO2 partial pressures of exhaled gas, O2 extraction, and O2 and CO2 exchange via the intestine were also determined, allowing the role of the intestine in total gas exchange in the weatherloaeh to be determined and compared with aerial gas exchange organs in other fishes. The alimentary canal is divided into three zones, an anterior glandular portion separated by a spiral section from the posterior, respiratory zone which has the greatest capillary densities and shortest gas diffusion distances. At rest (20°C), the intestine takes up about 20% of total O2 but accounts for less than 3 % of total CO2 elimination (gas exchange ratio = 0.08 for intestine). O2 extraction averages 50%. Increasing temperature causes only slight increases in total metabolic rate (Q10 for MOO2= 1.5-1.8), but highly significant increases in intestinal gas exchange relative to total gas exchange develop as temperature rises. Intestinal gas exchange also rises with decreasing O2 availability. A strong hypoxic drive and weak hypercapnic drive exist for aerial ventilation of the intestine, but are reduced or absent for aquatic ventilation of the gills. In spite of having to function in respiration, absorption, secretion and buoyancy regulation, the potential effectiveness of intestinal gas exchange is shown to be similar to that of other structures used for aerial gas exchange in facultative air-breathing fish.

Behavioral Testing of Mice Concerning Anxiety and Depression

2015 ◽  
Vol 223 (3) ◽  
pp. 151-156 ◽  
Author(s):  
Nina Schweinfurth ◽  
Undine E. Lang
Keyword(s):  
Environmental Influences ◽  
Sickness Behavior ◽  
Laboratory Research ◽  
Anxiety And Depression ◽  
Housing Conditions ◽  
Human Beings ◽  
Behavioral Testing ◽  
New Developments ◽  
Animal Trials ◽  
Resilience Factors

Abstract. In the development of new psychiatric drugs and the exploration of their efficacy, behavioral testing in mice has always shown to be an inevitable procedure. By studying the behavior of mice, diverse pathophysiological processes leading to depression, anxiety, and sickness behavior have been revealed. Moreover, laboratory research in animals increased at least the knowledge about the involvement of a multitude of genes in anxiety and depression. However, multiple new possibilities to study human behavior have been developed recently and improved and enable a direct acquisition of human epigenetic, imaging, and neurotransmission data on psychiatric pathologies. In human beings, the high influence of environmental and resilience factors gained scientific importance during the last years as the search for key genes in the development of affective and anxiety disorders has not been successful. However, environmental influences in human beings themselves might be better understood and controllable than in mice, where environmental influences might be as complex and subtle. The increasing possibilities in clinical research and the knowledge about the complexity of environmental influences and interferences in animal trials, which had been underestimated yet, question more and more to what extent findings from laboratory animal research translate to human conditions. However, new developments in behavioral testing of mice involve the animals’ welfare and show that housing conditions of laboratory mice can be markedly improved without affecting the standardization of results.

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