Impacts of ewe death and failure to rear a lamb on national production, profitability and greenhouse-gas emissions in New Zealand

Context Ewe death and lamb abandonment can contribute significantly to overall productivity and profitability of farming systems in New Zealand through impacts on lamb survival. Aims To find out how ewe death and failure to rear a lamb affect the production, profitability and greenhouse-gas emissions of the sheep meat industry through lamb and ewe losses from sheep farming enterprises across New Zealand. Methods Data collected in a national survey were examined to provide insight into the role of the fate of the ewe in influencing the provision of lambs and cull ewes to the sheep meat value chain. Key results At a national level, the impact of ewes surviving but not rearing a lamb was three times greater than that of ewe deaths. The combined outcome resulted in a predicted 2.5 million ewes not rearing a lamb, of approximately 15.5 million ewes being mated each year. If all farms performed at the level of the upper 15% of sheep enterprises, another 65,000 Mg sheep meat/annum would be produced. This productivity increase resulted in a potential increase in total greenhouse-gas emissions of 1.9%, whereas emissions intensity decreased by 12%. The value of changing the fate of the ewe is worth pursuing. The reduction in ewe mortality of 2.6% and ewe morbidity of 2.2% achieved by the top 15% of farmers resulted in an increase in gross margin of NZ$30/ewe mated more than the average, and over NZ$64/ewe mated more than for the lower 15% of reported farms. Conclusions If all farmers were to perform at a level similar to the top 15%, this would translate into a potential increase in farm gross margin of NZ$481 million at a national scale. Implications The differences reported here indicate that these types of gains are achievable and offer hope to the industry of future growth in productivity and profitability with the further implementation of current best practice.