Should I tup my ewe lambs this year?
and on Freeview 262 or Freely 565
Stephen Flanagan, Senior Beef and Sheep Advisor, College of Agriculture, Food and Rural Enterprise (CAFRE) outlines that a major benefit of breeding from ewe lambs, is that the generation time is reduced by a year allowing for faster genetic progress, optimising live weights, reproductive success or crossbreed trait benefits.
The success of such a breeding programme involving ewe lambs requires careful management and attention to detail.
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Ewe lambs need to have reached 60-70% of their mature bodyweight prior to tupping. This target is required to maximize conception rates and ensure good foetal development.
However, heavy feeding of very young female sheep (younger than five months of age) can reduce mammary gland development and subsequent milk yield, so this is not advised. For example, breeding from a Texel x Mule ewe lamb with a potential mature weight of 75kg must be between 45 - 50kg at time of tupping.
Ewe lambs can have a lower initial reproductive performance this is caused by various factors, with one being the age of onset of puberty. Whilst this can occur between 7 – 10 months of age it can be brought on earlier with the interaction of teaser rams. If using teaser rams, the teaser should be left in with the ewe lambs for 14 days before fertile rams are introduced.
Correct ram selection is vital, mate with ram breeds with a smaller than average mature size and use breeds with evidence of lower birth weights. Ideal groups size is 1 ram to 25-30 ewe lambs and grazed in small fields or paddocks.
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Post conception, lower embryo survival has been demonstrated with studies suggesting greater than a 2-fold increase in embryonic losses from ewe lambs when compared to mature ewes in the first 30 days following conception.
To help counteract this, for a few weeks at tupping, mate on lower grass heights of poorer nutrition which can help slow down the amount of hormones filtered out by the liver which in return will hopefully result in higher scanning results.
This is a delicate balance as ewe lambs still need to be gaining at least 250g/day for a further six weeks post tupping and then lowered to 130-150 g/day up until six weeks before lambing to aid in embryonic survival.
Scanning should take place around day 60 of pregnancy which then leaves enough time to manage them accordingly for either slaughter or to keep for a further year. The scanning results also allows for more accurate feeding programme based on litter size.
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During early and mid-pregnancy, ewe lambs need about 20% more feed than mature ewes of a similar weight to sustain their continuing development. Do not overfeed in the last week before lambing and target feed only for maintenance and pregnancy, not growth. Feeding for growth at this point will create large single lambs and potentially increase lambing difficulties.
From an environmental aspect breeding ewes as ewe lambs can also provide additional benefits, for example by reducing the farm carbon footprint. When using these results within a commercial carbon footprinting tool, the carbon footprint was 5% lower for a system using ewe lambs rather than hoggets (AHDB).
Those farmers who are part of the Business Development Groups (BDG) who already financially benchmark their business with CAFRE can also now get a carbon benchmark completed.