Recently, I saw a two-year-old autumn calver that had been lame for a while. The onset of lameness coincided with her spending more time on concrete. She had been transitioned onto a feed pad two weeks before calving. She gave birth to a dead calf. Due to her lameness, she was kept with a sickies mob and allowed ad lib maize. The lameness increased in severity, and laminitis was suspected. She had a corrective trim to remove overgrown horn and was turned out into a flat paddock to recover.
Despite this, the cow’s lameness worsened, especially after being walked around a concrete yard to assess her gait. She carried a lot of weight on her heels, causing the toes to be tilted upward, see Figure 1. She had an arched back when walking and was struggling to move. The prognosis was poor, and she was euthanised.
A postmortem exam showed signs of chronic laminitis, see Figure 2 and 3.
All four feet had a pink discolouration around the white line, due to haemorrhage of the corium. The corium is like the quick in the human fingernail. It supports the claw bone, contains blood vessels and nerves and is responsible for producing new hoof. Growth rings were also seen. These are grooves which occur when horn growth is disrupted. Horn typically grows ~1cm per month. So, the main laminitic event here looks to have happened ~5 months ago. Multiple rings would indicate multiple bouts of laminitis.
Laminitis is a multifactorial disease involving inflammation of the corium. Damage to the corium impairs hoof development. Where all feet are affected, it’s likely the animal has been systemically unwell. There are several risk factors for laminitis including nutritional factors (e.g. excessive carbohydrate intake/low fibre diet), metabolic disease and infections (e.g. mastitis, metritis, liver abscesses). Heifers are more prone to laminitis during calving, likely due to the massive metabolic and nutrition changes occurring. Signs of laminitis range from nothing to an animal with a stiff gait, a reluctance to move and a posture where the limbs are placed further forward than normal. It can be a single event which carries a reasonable prognosis. Alternatively, it can be a chronic illness. Once the hooves start to become misshapen, regular corrective trimming is required and they are at risk of other types of lameness e.g. white line disease and sole ulcers. This combined with the associated pain carries a poor prognosis.
