The Weaning Process – Expressing your Stocks’ Full Potential

Most of us think of, and treat, weaning as a date on the calendar – something that gets ticked off and moved on from. For the lambs however, weaning is the biggest event in their lives and undoubtedly the most stressful. They are separated from their mums’, taken off milk, often have to adjust to a new feed source, exposed to the stress of yarding, dogs and people, and this all happens very abruptly.

Modern stock have a lot of genetic potential – but if they are not fed well then that potential will not be fully realised. After making that investment you must then give them the chance to express it – which means fully feeding them, especially at key times such as premating, late-pregnancy and lactation, and when they are young growing stock.

If post-weaning growth rates are lower than you would like has a weaning check played a part in this?

The two main areas that will impact how the weaning process will affect the young lamb are:

• The amount of stress it places the lamb under:

  • This comes from handling by people and dogs, changes to their environment, and changes to their management and routine such as being removed from their mums

• The change in feeding the lamb undergoes:

  • Remember we are feeding the bugs in the rumen, not the lamb itself

    – the lamb lives off acid produced by the rumen bugs and they also digest the rumen bugs as a source of protein. Weaning means the final transition from a monogastric animal (milk is main energy source) to a full ruminant (forage feeds bugs in rumen).

Over the ditch feeding grain every few days for a week before and then several after weaning is used to help with rumen transition – it suits their systems as sheep are then accustomed to grain in case of drought. The lambs also get used to people coming into the paddock to feed out in the few days before being handled before weaning, reducing that stress. Here in NZ a more realistic option may be making sure lambs and their mums are on the high quality feed the lambs will be weaned onto before this happens – so lambs and their rumens are used to it.

Any changes you can make to your normal weaning process that will reduce stress on the lambs and ease the transition of the rumen bugs to their new diet will help make this change easier. This can translate to a couple of kg either way – lost or gained – which could add up down the road to several kg for a hogget mated. Getting the rumen bugs cranking also optimises the output of rumen protein – which helps growth rates and resilience against parasitism.