Early neonatal lamb mortality: postmortem findings

Abstract

An investigation of stillbirth and early neonatal lamb mortality was conducted in sheep flocks in Norway. Knowledge of actual causes of death are important to aid the interpretation of results obtained during studies assessing the risk factors for lamb mortality, and when tailoring preventive measures at the flock, ewe and individual lamb level. This paper reports on the postmortem findings in 270 liveborn lambs that died during the first 5 days after birth. The lambs were from 17 flocks in six counties. A total of 27% died within 3 h after birth, 41% within 24 h and 80% within 2 days. Most lambs (62%) were from triplet or higher order litters. In 81% of twin and larger litters, only one lamb died. The most frequently identified cause of neonatal death was infectious disease (n = 97, 36%); 48% (n = 47) of these died from septicaemia, 25% (n = 24) from pneumonia, 22% (n = 21) from gastrointestinal infections and 5% (n = 5) from other infections. Escherichia coli accounted for 65% of the septicaemic cases, and were the most common causal agent obtained from all cases of infection (41%). In total, 14% of neonatal deaths resulted from infection by this bacterium. Traumatic lesions were the primary cause of death in 20% (n = 53) of the lambs. A total of 46% of these died within 3 h after birth and 66% within 24 h. Severe congenital malformations were found in 10% (n = 27) of the lambs, whereas starvation with no concurrent lesions was the cause of death in 6% (n = 17). In 16% (n = 43) of the lambs, no specific cause of death was identified, lambs from triplet and higher order litters being overrepresented among these cases. In this study, the main causes of neonatal lamb mortality were infection and traumatic lesions. Most neonatal deaths occurred shortly after birth, suggesting that events related to lambing and the immediate post-lambing period are critical for lamb survival.

Refining livestock mortality indicators: a systematic review

“…In sheep, two papers noted that stillbirth and perinatal mortality rates were higher than at any age ( Holmoy & Waage, 2015 ); Voigt et al , 2019 ), while other authors report the largest proportion of mortalities occurred within 24 hours of birth ( Binns et al ., 2002 ), or within first week ( Gokce & Erdogan, 2009 ; Gokce et al ., 2013 ; Khan et al ., 2006 ). Holmoy et al . (2017) reported that 80% of neonatal lamb mortalities occurred within the first two days of life.…”

Descriptive analysis of ovine mortality in sentinel sheep flocks in Ireland

“…Holmoy et al 42 suggested that the relative frequency of certain diagnosed causes of perinatal death (eg, dystocia or hypogammaglobulinaemia) in flocks which lamb indoors may differ from those which lamb outdoors due to differences in the intensity of lambing surveillance. Data on whether sheep were due to lamb indoors or outdoors were unavailable in this study and it is possible, therefore, that the overall number of submissions, and those of perinates specifically, may have been influenced by the lambing system on farm.…”

Antimicrobial resistance and phenotypic and molecular detection of extended-spectrum β-lactamases among extraintestinal Escherichiacoli isolated from pneumonic and septicemic sheep and goats in Rajasthan, India

“…The presence of petechial hemorrhages on different organs such as the heart and spleen indicated septicemia. Holmoy et al [18] recorded that E. coli existed among 65% of the septicemic lambs. Ruminants, particularly sheep and cattle, are recognized as reservoirs of E. coli (STEC) strains [19].…”