Factors involved in high ewe losses in winter lambing flocks grazing dual-purpose wheat in southern New South Wales: a producer survey

A comparative survey was undertaken with 43 sheep producers in southern New South Wales using a semistructuredinterview to investigate factors associated with high ewe mortality rates in winter lambing flocks grazing dualpurposewheat. Participants were classified as either control (n = 23), who had not observed abnormally high ewe deaths, orcase (n = 20), who had observed abnormally high ewe mortality rates when sheep grazed dual-purpose wheat. Ewe lossesassociated with grazing wheat were higher in the case group compared with the control group (8.6 vs 1.8%; P < 0.001) andthere was also more deaths attributed to metabolic disease (3.4 vs 0.6%;P< 0.05).Ahigher proportion of control respondentshad provided magnesium or sodium supplementation to ewes grazing wheat (P < 0.05). The body condition score of ewesentering the grazing period was significantly higher in the control group (3.2 vs 2.8; P < 0.05). The proportion of respondentswho fed roughage to ewes grazing wheat did not differ significantly between control and case groups (48 vs 35%). A higherproportion of respondents in the case group had supplied grain to ewes (25 vs 0%; P < 0.05), which may have been associatedwith the lower body condition of sheep in these flocks compared with the control group. It was concluded that supplyingad libitum access to mineral supplements that include magnesium, sodium and possibly calcium, and maintaining adequatebody condition score can reduce the risk of high ewe mortality rates when reproducing ewes graze dual-purpose wheat.