Developing a modified Apgar scoring system for newborn lambs

Abstract

The Apgar (appearance, pulse, grimace, attitude, respiration) score is an accepted method for assessing newborn viability in humans and domestic animals. The purpose of this research was to modify an existing Apgar scoring system for lambs and compare Apgar score with litter size and birth order, as well as time-to-stand and time-to-suckle. Polypay lambs (n = 75) delivered naturally were used for this study. Pulse (<100 bpm = 0; 100-175 bpm = 1; >175 bpm = 2) and respiration (<45% SpO₂ = 0; 45-65% SpO₂ = 1; >65% SpO₂ = 2) were measured with a pulse oximeter attached to the lamb's ear. Appearance, grimace, and attitude were assessed using mucous membrane color (cyanotic = 0; pale = 1; pink = 2); response to nose stimulation (no response = 0; moves head slightly = 1; shakes head = 2); and response to rump stimulation (no movement = 0; moves but no attempt to stand = 1; attempts to stand = 2), respectively. The Apgar score was measured within 5 min of birth (T0), 15 min (T15) and 60 min (T60) after birth. The time-to-stand and time-to-suckle were recorded and compared to Apgar scores. Apgar scores did not differ by litter size or birth order. There were no significant correlations between the Apgar scores and time-to-stand. There was a moderate positive correlation between attitude and time-to-suckle at T0 (R² = 0.467), which may affect the ingestion of adequate colostrum in a timely manner. Producers may choose to consider using Apgar scoring so that assistance can be provided to lambs before serious complications arise.

Keywords: Attitude; Heart rate; Oxygen saturation; Sheep; Suckle.