top of page

Dozer & Lucerne

Unforeseen Consequence of Feeding Alfalfa (Lucerne)....

Tammy lives near Houston, Texas and contacted us when her OTTB 'Dozer' suddenly became extremely agitated:

“He’s never behaved in this way, it’s sudden and dramatic for him. He even charged at me Friday and has never ever shown aggression in the 3 yrs I’ve had him.

I had a Chiro and teeth done Saturday but he is still pinning his ears at me. Maybe it’s ulcers? Not sure but I want to do everything I can to help get him back!"

Tammy Westcott, Houston, Texas

We asked what Dozer’s diet consisted of and it included Alfalfa Hay and Alfalfa pellets. So instead of going down the ulcer route we suggested to first remove the Alfalfa from his diet.

Tammy said: “You know what, I started feeding the Alfalfa on January 20th which I never did before. He’s always been on Timothy or coastal (grass) hay. I thought in colder weather the alfalfa would be better for him and was told so by a nutritionist group on facebook - Plus someone told me Timothy pellets are higher in starch/carbs and not as good for them as alfalfa??

19.2.21 Just 5 days later: “I just wanted to update and say thank you! I immediately removed the alfalfa hay on the 14th as you recommended and have seen a dramatic change for the better. That MUST have been the issue.”


In the first part of this video you can see how aggressive and miserable after two weeks using alfalfa hay and pellets. 
In the second half it is Day 5 after removing alfalfa completely and switching only to Timothy and free choice grass hay.

Whether horses can tolerate Alfalfa or not DEPENDS on what the rest of their diet consists of and their CURRENT METABOLIC STATE. Dozer’s diet already contained short, green rye-grass.

He had been doing fine until his forage was switched to alfalfa hay and alfalfa pellets. We know from many years of experience that feeding alfalfa (Lucerne) ON TOP OF cool season grasses can be disastrous for the poor horse and dangerous for the handler/rider. The high potassium, nitrates and crude protein of alfalfa added to the high potassium, nitrates and crude protein of rye-grass overwhelms their metabolism.

The irony of Dozer’s story is that the first thought to explain the discomfort was 'ulcers' for which the popular advice is to feed alfalfa (for the calcium). But, as we have observed for some horses, this does not work.


From our investigations it is likely because the high potassium, nitrates and crude protein aspects overwhelm the calcium aspect. In Dozer’s case he got worse not better when alfalfa was added. The sugars aspect was not involved because he improved dramatically on the higher sugar grass hay option.

We have seen many other examples where the feeding of alfalfa/Lucerne to horses has resulted in various unintended consequences.

The moral of the story: It is not just the attributes of the particular feed item that should be used to evaluate whether it would be suitable for a particular horse– it is necessary to make a decision in the context of the horse’s total diet and also his current metabolic health.

There are many feed items that do not cause any problems when fed to normally functioning horses but which have adverse effects when fed to a horse whose metabolism is compromised - as is the case with grass-affected horses!.

bottom of page