[Oopsiboughtasheep]

Rockies do a SC Sheep selenium cobalt lick 2 x 10kg yellow  blocks they aren't too expensive i use them as a summer mineral block probably worth a try and if it solves the problem there's your husbandry answer

I've just got those too.

[SallyintNorth]

Our vet suggested that our grass might be deficient in selenium and/or cobalt, and indeed when I gave them a multi-vitamin and mineral drench, they improved rapidly (not conclusive proof, but enough to give rise to suspicion). The over-wintered lambs have then been fine all winter, but now they're off hay and onto grass, there are again a few mucky bums about.

My question is, how do I go about proving that this is what's going on. Pasture analysis?  Blood test?  I'm nervous about giving a supplement that is not required, in case they overdose somehow - am I right to be?.

Then, if that is the problem, what's the best way to correct it? A regular drench would be easiest, but I can't find anything on how often to give it. The alternative is to give a slow release bolus which should last for several months.

Any thoughts? 

You live in the north of the UK and have grassland (agric classification, not arable, I mean) - your land is copper, cobalt and selenium deficient.  No test required! 

I have no experience of blouses in sheep, but if you get a chelated drench, the minerals are released slowly over 6-8 weeks, and you will probably find that once or twice a year is plenty.  If you know when the lambs need it, that's one, and the other at tupping time to ensure the ewes and tup are in tip top fettle.

Chelated drenches cost quite a bit more than the cheaper sort, but will give you a far better result because of the slow release.

I'd try it this year on the lambs and see what happens.  Or maybe try it on half... 

The one I used to use was Carrs' Ovithrive

[SallyintNorth]

I have no experience of boluses in sheep, either.  I left the autocorrect error there because it made me laugh

[Foobar]

You live in the north of the UK and have grassland (agric classification, not arable, I mean) - your land is copper, cobalt and selenium deficient.  No test required! 

It's not as simple as that though is it?  Different types of grasses and legumes are able to pull differing amounts of minerals out of the ground.  So the make up of your pasture grasses is as important as the local soil/rock types.  Also if you live near any industry then you could get fallout from that which could be creating mineral lock-up problems or altering the mineral analysis.  Also the amount of rainfall you get can have an impact etc.
Just get the grass tested - that is the primary input of the sheep so that is what you should look at first.

[Womble]

Thanks all.  I'll have the grass tested once it's growing properly, and will report back  .