Hypoxia in Neonatal Calves: Effect on Selected Metabolic Parameters

¹ Department of Animal Science, North Carolina State Universlty, Raleigh 27695-7621

The effect of reduced oxygen tension in arterial blood (hypoxic hypoxia) for 24 h postpartum on selected metabolic parameters was studied in 12 neonatal calves. During this period, inspired air for hypoxic calves contained 10.5% O₂, whereas that for normoxic calves contained 21% O₂. After 24 h, inspired air for all calves contained 21% O₂. Three dietary treatments also were imposed during the initial 24-h period: colostrum at 0 and 12 h, whole milk at 0 and 12 h, or fasting. All calves were fed colostrum at 24, 36, and 48 h and whole milk at 60 and 72 h. Parameters included plasma glucose, lactate, fructose, and IgG; arterial blood gases; and pH.

Arterial partial pressure of oxygen was maintained near 25 mm Hg throughout the period of hypoxia. Arterial partial pressure of carbon dioxide was unchanged during the period of hypoxia ( 45 mm Hg) but was lower (39 mm Hg) in posthypoxic calves. Glucose tended to be lower in hypoxic calves; however, this difference was not statistically significant. Hypoxic calves had significantly higher plasma lactate concentrations contributing to a progressive primary metabolic acidosis.

Key Words: calves • hypoxia • blood gases

Submitted on October 15, 1990
Accepted on January 4, 1991