My old friend bloat. I can remember those wonderful days of missing out
on meals day after day watching 180 of 200 cows float across the fence
lines blown up like balloons. It was one of our worst problems and part
of the reason we moved into organics. If the grass was green any stock
type was prone to blow. One year we dried the cows off a month early
just to have a break from chasing bloat.
So for my 2 cents worth.!!!
There is only one rule you need to know about bloat and that is there
are no rules.
All the suggestions put forward work to some degree. I would suggest
that those that are not grazing clover / rye grass pastures will have
less problems. As digestibility has something to do with it.
There is a suggestion that your sodium / potassium ratio has an impact.
In some quarters this has been questioned, but many farmers who add Na
to there fert (50 - 100kg/Ha) have seen a marked decrease in bloat levels.
It has taken us many years but through breeding and improved soil
fertility balance we now have no more than the odd case every now and
again. Usually for those few days when the spring growth starts. If I
see a cow a bit puffy then the next few days I would add homoeopathic
colchicum to the water trough.
For those more chemically orientated you cannot beat drenching or a
bolus. The majority of NZ farmers would drench each milking. The main
drench families would be pluronic and alcohol based products. The bolus
has been rumensin based and now a rumensin product has just been
approved for drenching.
Trough treatment is good as well but not as reliable as drenching.
Weather and other water sources has an impact on the amount of water
that the cows will drink. Don't get caught like some of us have. Having
been using a pluronic product which had been added to the troughs we
moved on to the "new approved" alcohol product. Bloat went through the
roof and after many days of fast while chasing bloated cows we learn,t
that the two products do not mix and cancel each other out. So we had to
physically drain our troughs and then add the new product.
The white oil sprayed on the pastures is effective but rain has an
impact and if areas miss spraying then bloat can still occur.
So it really depends on what levels you experience bloat at.
We found the worst days for bloat were usually after a frost when the
cows would eat frozen grass and then within a couple of hours the
temperatures would be around 15 - 20 degrees. It was as though the grass
was "cooking" in the animals stomach.
Watch out around the full moon. Usually there is more moisture (heavier
dews etc) which brings more bloat.
Regards
Ian Buckingham
New Zealand
