Sheep eating Bracken

metalwood

My ewes are on good grass at the min but seem to be eating the Bracken around the ditches.:eek:

Are they lacking in something? Is it harmful to them?

Thanks

The_Conductor

metalwood wrote: »

My ewes are on good grass at the min but seem to be eating the Bracken around the ditches.:eek:

Are they lacking in something? Is it harmful to them?

Thanks

Can be a sign of thiamine deficiency.

Its a possible indication of trouble- I say possible- because some breeds of sheep will habitually eat bracken without anything whatsoever being wrong with them- and its actually very common in certain areas (mountain and hill sheep appear to actually seek out bracken).

Souterrain

smccarrick wrote: »

Can be a sign of thiamine deficiency.

Its a possible indication of trouble- I say possible- because some breeds of sheep will habitually eat bracken without anything whatsoever being wrong with them- and its actually very common in certain areas (mountain and hill sheep appear to actually seek out bracken).

Isn't it the other way around - don't ferns cause thiamine deficiency? I googled this and it looks like sheep don't get it much.

http://www.ars.usda.gov/Services/docs.htm?docid=9859

The_Conductor

Souterrain wrote: »

Isn't it the other way around - don't ferns cause thiamine deficiency? I googled this and it looks like sheep don't get it much.

http://www.ars.usda.gov/Services/docs.htm?docid=9859

In sheep thiamin deficiency is normally a result of acute lactic acid rumen generation- which inhibits the microbes who normally produce B vitamins from doing do. Eating grass seeds- or cereals, is actually more likely to cause the thiamin deficiency than anything else- as they generate more acidic conditions in the rumen than other food types. This is why thiamin deficiency occurs in the main at this time of the year.

Sheep who suffer from thiamin deficiency sometimes seek out bracken- I don't know why (as bracken consumption can cause all manner of problems in its own right- most notably neuralogical issues in sheep and goats).

There is a very short paragraph on this in Merck (veterinary handbook).

johngalway

metalwood wrote: »

Is it harmful to them?

Can't give you a scientific answer. I used to have a large patch of bracken on my farm, and when it would be growing the sheep would nibble at the fronds. Also I notice this year, two years after spraying off most of the bracken, the sheep are demolishing most of the few plants that pop up. Also my Dad has some bracken on his land. I don't believe we've seen any negative effects from it, but as I started out saying I can't give you proper scientific advice. Either way, I reckon a farm is better off without it.

Souterrain

smccarrick wrote: »

In sheep thiamin deficiency is normally a result of acute lactic acid rumen generation- which inhibits the microbes who normally produce B vitamins from doing do. Eating grass seeds- or cereals, is actually more likely to cause the thiamin deficiency than anything else- as they generate more acidic conditions in the rumen than other food types. This is why thiamin deficiency occurs in the main at this time of the year.

Sheep who suffer from thiamin deficiency sometimes seek out bracken- I don't know why (as bracken consumption can cause all manner of problems in its own right- most notably neuralogical issues in sheep and goats).

There is a very short paragraph on this in Merck (veterinary handbook).

Thanks so much that’s a brilliant book and did you know you can read it all free in the internet by opening this page http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/210400.htm




I think I found the paragraph you are talking about using the search box but I have read it a couple of times and I am not sure I understand it.

It says -


Poisoning in nonruminants is due to a thiaminase; the effects are essentially those of vitamin B1 deficiency, with myelin degeneration of the peripheral nerves. Horses seem to be particularly susceptible, while disease in pigs is rare. Thiamine deficiency is generally not a problem in ruminants because the vitamin is synthesized in the rumen, but polioencephalomalacia ( Polioencephalomalacia: Introduction) associated with impaired thiamine metabolism in sheep has been attributed to consumption of bracken fern and rock or mulga fern ( Cheilanthes sieberi ) in Australia.

Isn't nature very strange if a sheep that is deficient in thiamine goes looking for a plant that will make her worse. It maybe explains why it can be hard to keep sheep alive around here sometimes ! They have a death wish I always say.

Our vet told us that she thought that bracken ferns could make our sheep and our pony deficient in thiamine but I think she has got it mixed up somehow.

Sue