The interval between birth and sternal recumbency as an objective measure of the vitality of newborn calves.

Abstract

The time from birth to attaining sternal recumbency (T-SR) was recorded for 219 newborn calves in order to evaluate its use as a parameter for diagnosing vitality. Calves were defined as vital if they received routine care without medical treatment and survived seven days from birth without any symptom of illness (n = 192). Those which did not fulfil these conditions were categorised as non-vital (n = 27). Ten calves were born spontaneously and the others were delivered either by caesarean section (n = 105), normal extraction (n = 78) or forced extraction (n = 26). The mean (+/- sd) T-SR values of the vital calves in these delivery groups were: 4.0 +/- 2.2, 4.5 +/- 3.1, 5.4 +/- 3.3 and 9.0 +/- 3.3 minutes, respectively. Jugular blood gas and pH measurements were performed at several fixed times after birth until pH and base excess had reached values of over 7.2 and more than -5.0 mmol/litre, respectively. Mean pH and base excess values of vital calves 10 minutes post partum were significantly higher and lower, respectively, than those of non-vital calves. Forcefully extracted calves had longer T-SR, more serious acidosis, recovered more slowly from acidosis, died more, and exhibited trauma more frequently. A T-SR of at least 15 minutes had a predictive value of 84 per cent for non-vitality, while 10 minute pH values of less than 6.9 had a lower predictive value, namely 68 per cent, for non-vitality. Correlations between T-SR values and 10 minute pH and base excess values were moderate, whereas correlations between T-SR values and PCO2 values were weaker still and much more dependent on the type of delivery. It is concluded that T-SR determination is a valuable, practicable and objective diagnostic tool for estimating the condition of newborn calves during the first 15 minutes of life. The diagnostic value of a single pH measurement on the jugular blood of a neonatal calf is doubtful.