A common complaint throughout the country on some farms at the moment seems to be to low milk fat. This can have many causes but one condition that I would like to discuss is SARA, or subacute ruminal acidosis.
Just because milk fat is low does not mean you have a SARA problem, however it is worth investigating where there is a significantly low milk fat percentage. This is not to be confused with grain overload or traditional acidosis, but more of a constant low grade acidosis which affects rumen function.
It is important to remember that the rumen in the cow is the main engine and is where grass is converted to energy and protein is broken down and absorbed. It is a complicated microbial bath which can have knock on effects on production when underperforming.
As an aside, whenever I look at nutritional issues on farm I will always look at ruminal score. This involves crudely assessing the size and consistency of the rumens in cows to determine a rough guide to ruminal health at herd level. We will also look at faecal consistency as a way of assessing adequate ruminal function.
As a starting point for nutrition on any farm, I always advocate plenty fresh available water for cows to drink. They also need a good fibre source and I will always recommend that NaCl is supplemented in cow’s diets all year round. Salt is a cheap mineral and plays a huge role in a healthy functioning rumen.
So why could SARA affect the cows out on grass? What is thought to happen is that spring grass is very high in sugars and low in fibre and in early lactation this can affect the rumen and Ph, which can affect milk fat production. Here are some indicators:
Increase in lameness or laminitis.More than 10% of cows have milk fat percentage of less than 2.5%.
More than 10% of cows have milk fat less than protein by 0.4 %.There is poor faecal consistency.Less than 80% of resting cows are not ruminating (crude indicator).At farm level, we can use Ph meters to check a group of cows to look for rumen Ph lower than 5.5, however it is a complicated procedure. In these cases I like to bring in an independent nutritionist to assess the overall diet and make recommendations.
Some simple tips are the use of buffers such as sodium bicarbonate or other premade precursors that help rumen function. One difficult thing to do on a grazing herd is the adding of fibre source such as hay, silage or straw, but it can be hugely beneficial. This fibre will restore normal rumen function slowly over time in my experience.
This is only a brief overview of a complex nutritional condition. I personally think that these type of scenarios benefit from the involvement of an experienced nutritionist working with you, your vet and other advisors.
A common complaint throughout the country on some farms at the moment seems to be to low milk fat. This can have many causes but one condition that I would like to discuss is SARA, or subacute ruminal acidosis.
Just because milk fat is low does not mean you have a SARA problem, however it is worth investigating where there is a significantly low milk fat percentage. This is not to be confused with grain overload or traditional acidosis, but more of a constant low grade acidosis which affects rumen function.
It is important to remember that the rumen in the cow is the main engine and is where grass is converted to energy and protein is broken down and absorbed. It is a complicated microbial bath which can have knock on effects on production when underperforming.
As an aside, whenever I look at nutritional issues on farm I will always look at ruminal score. This involves crudely assessing the size and consistency of the rumens in cows to determine a rough guide to ruminal health at herd level. We will also look at faecal consistency as a way of assessing adequate ruminal function.
As a starting point for nutrition on any farm, I always advocate plenty fresh available water for cows to drink. They also need a good fibre source and I will always recommend that NaCl is supplemented in cow’s diets all year round. Salt is a cheap mineral and plays a huge role in a healthy functioning rumen.
So why could SARA affect the cows out on grass? What is thought to happen is that spring grass is very high in sugars and low in fibre and in early lactation this can affect the rumen and Ph, which can affect milk fat production. Here are some indicators:
Increase in lameness or laminitis.More than 10% of cows have milk fat percentage of less than 2.5%.More than 10% of cows have milk fat less than protein by 0.4 %.There is poor faecal consistency.Less than 80% of resting cows are not ruminating (crude indicator).At farm level, we can use Ph meters to check a group of cows to look for rumen Ph lower than 5.5, however it is a complicated procedure. In these cases I like to bring in an independent nutritionist to assess the overall diet and make recommendations.
Some simple tips are the use of buffers such as sodium bicarbonate or other premade precursors that help rumen function. One difficult thing to do on a grazing herd is the adding of fibre source such as hay, silage or straw, but it can be hugely beneficial. This fibre will restore normal rumen function slowly over time in my experience.
This is only a brief overview of a complex nutritional condition. I personally think that these type of scenarios benefit from the involvement of an experienced nutritionist working with you, your vet and other advisors.
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