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Oxygen Transport and Utilization during Feeding in the Young Lamb
Author(s) -
Grant Daniel A.,
Fewell James E.,
Walker Adrian M.,
Wilkinson Malcolm H.
Publication year - 1997
Publication title -
the journal of physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.802
H-Index - 240
eISSN - 1469-7793
pISSN - 0022-3751
DOI - 10.1111/j.1469-7793.1997.195bi.x
Subject(s) - cardiorespiratory fitness , oxygen , heart rate , zoology , anesthesia , cardiac index , artery , cardiac output , medicine , blood pressure , cardiology , chemistry , biology , organic chemistry
1 Five lambs (19–27 days old) were studied to determine the effects of feeding on cardiorespiratory function. 2 Each lamb was instrumented to record cardiac output, aortic and pulmonary artery pressure and arterial and mixed venous oxyhaemoglobin saturations ( S a,O 2 and S v,O 2 ). 3 During feeding, arterial haemoglobin desaturated and resaturated sequentially during the periods of sucking and non‐sucking. The nadir of these S a,O 2 desaturations (83 ± 2%, mean ± s.e.m. ) was significantly lower than the baseline value (92 ± 2%, P ≤ 0.05, ANOVA). S a,O 2 returned to the baseline level between periods of sucking. S v,O 2 also decreased (55 ± 3% baseline, 46 ± 3% sucking, P ≤ 0.05) but, in contrast to S a,O 2 , it remained significantly lower than baseline levels in the pauses between periods of sucking. 4 Arterial pressure increased during feeding (94 ± 4 mmHg baseline, 113 ± 6 mmHg feeding, P ≤ 0.05), while heart rate and cardiac index did not change. 5 Total body oxygen consumption rose during the pauses between sucking periods (10.9 ± 1.1 ml O 2 min −1 kg −1 baseline, 13.9 ± 1.2 ml O 2 min −1 kg −1 non‐sucking, P ≤ 0.05) and was provided for by a significant increase in total body oxygen extraction as systemic oxygen transport was unchanged. 6 Our results reveal that during feeding in young lambs oxygen consumption increases and body stores of oxygen (e.g. S v,O 2 ) become depleted; this combination may promote rapid arterial desaturation and cyanosis during feeding.