Lucerne for adult rabbits can be deadly. Rabbits have a low level of calcium tolerance, and excess calcium goes through the bloodstream, and into the kidneys, and then into the bladder.

In the kidneys, it can form stones, or calcification of the kidneys, and in the bladder, it can cause sludge or stones.

Any of these can be deadly, and rabbits needs to be monitored well for calcium or sludge in their wee. Healthy rabbits will just excrete the excess calcium, in the form of a white powder in the wee, but in unhealthy (thus its not just calcium to be excreted, but the way their systems work, or the food given, complicates the calcium) rabbits, it can cause sludge compounds, which cause little sandy grits and even stones in extreme cases.

Sludge can really hurt when passing through the urethra and causes bladder infection as well as lower urinary tract infections; or buns can try hold their wee in and this cause other issues. In the end, this all cause wet bottom syndrome, and leave the rabbit to get flystrike. If ever you see wee above your bunny’s tail when they used the litterbox, or you see them hunch or strain, it is needed to investigate and check the bladder and wee.

Sludge or stones are harder to treat than giving the correct diet, but even some buns getting the correct diet is sludge prone; this is genetic, and a more specialized diet or treatment schedule is needed. This is to do with the way they handle their calcium-phosporus and other element digestion, and is genetically part of their system.

Keep a look out if your bunny’s wee is clear and if they are straining or hunched when they wee. But also make sure to NOT give lucerne as hay to adults, but maybe half a handful of sticks than leaves, as a treat and for dental health, once a week, or once every 2 weeks, or avoid it if your bun has good dental health or other chew sticks.

Lucerne Sticks has less calcium in than the leaves, and can help to grind down dental spurs forming, together with lawn grass, but never overfeed lucerne. Rabbits suddenly getting lucerne when they are not used to it, can also cause immense diareah because of its richness.

Also avoid giving too much calcium rich foods like spinach, limit kale and parsley and never give both together. Watch out for certain plants in your garden, like clover, that has other compounds like oxalates, that further complicate and cause sludge.