increase font size
Professor Paul Kenyon.
Breeding hoggets at eight months of age can improve a ewe’s lifetime productivity.
However, if they are not well managed, it can have long term negative effects on ewe live weight and reproduction.
Current live weight targets for hoggets prior to breeding are a minimum of 40kg. However, some farmers are achieving pre-breeding weights of 45 to 50kg. It is unclear if there may be unforeseen consequences of achieving these greater pre-breeding weights.
The Sheep Research Centre at Massey University – led by PhD student Emmanuelle Haslin, with funding from B+LNZ – has done an experiment to determine the impacts of heavier pre-breeding live weight of hoggets on their subsequent live weight, reproductive performance and the growth of their progeny.
Twin-born Romney hoggets were allocated to one of two groups at weaning. The ‘Heavy’ group was preferentially fed until breeding to achieve an average live weight of 48.0kg, and the ‘Control’ group was managed to achieve an average pre-breeding live weight of 44.8kg.
From breeding at eight months of age onwards, both groups were managed and grazed together. The results showed that there was a 28% increase in pregnancy rate, a 6% increase in litter size which resulted in a 59% increase in lambing percentage in the heavy group compared to control group.
Hoggets in the heavy group were heavier than control hoggets throughout pregnancy. However, they did not differ during lactation or post weaning. Lamb live weights at birth, docking and weaning and lamb survival to weaning did not differ between groups.
As 2-tooths, there were no differences in the percentage ewes mated or pregnancy rate. There were also no differences in scanning or lambing percentages. Live weights of 2-tooths did not differ between groups.
Lambs born to the heavy and control 2-tooths had similar live weights and survival rates to weaning.
In conclusion, although hoggets in the heavy group had improved reproductive performance in their first breeding season, it had no impact on their live weight or reproductive performance as a 2-tooth. This suggests that hoggets can be bred at live weights up to 50kg to improve their reproductive performance without any impacts from their greater live weight.
• Paul Kenyon is a professor in sheep husbandry and deputy head of the agriculture & environment school at Massey University.
Can discarded beef skins become premium dog food? Would camel milk work for your morning flat white? These are just two of the questions that will be answered next week at an international conference in Palmerston North.
Changing skill demands and new job opportunities in the primary sector have prompted Massey University to create a new degree course and add a significant major into another in 2025.
Always be on the lookout for new job opportunities and get outside your comfort zone.
She came all the way from a sheep station in Tasmania especially to be presented with the top prize in this year's Massey University agriculture, horticulture and environmental science award.
Massey University is tweaking the format of its agricultural courses.
The a2 Milk Company (a2MC) says securing more China label registrations and developing its own nutritional manufacturing capability are high on its agenda.
Stellar speakers, top-notch trade sites, innovation, technology and connections are all on offer at the 2025 East Coast Farming Expo being once again hosted in Wairoa in February.
As a guest of the Italian Trade Association, Rural News Group Machinery Editor Mark Daniel took the opportunity to make an early November dash to Bologna to the 46th EIMA exhibition.
Livestock can be bred for lower methane emissions while also improving productivity at a rate greater than what the industry is currently achieving, research has shown.
OPINION: The New Zealand red meat sector, with support from the Government, has upped the ante to retain and expand its niche in the valuable Chinese market - and the signs are looking positive.
Keratin extracted from New Zealand wool could soon find its way into products used to minimise osteoporosis, promote gut health, and other anti-inflammatories, says Keraplast chief executive Howard Moore.
