Which cows should be on the trim list?

Many farms struggle to prioritise the right cows to put in front of the trimmer. With increased use of screening approaches, such as weekly observation of cows or full mobility scoring every 1–2 weeks, trimmers see some cows repeatedly and often needlessly within a few weeks of the last trimming. Vet Nick Bell explains more.

Here is the priority list, in rough order of importance:

Any newly lame cows not yet seen and not on a chronic and repeatedly lame list (below). Ideally, look for lameness daily and treat cows by the on-farm trim team the day they are seen. Add them to the treatment board, Whatsapp list or other App or software for immediate action. Lameness is an emergency. The cure rate is lower the longer you leave it, with the digital cushion becoming scarred, new bone formation on PIII, digital dermatitis spreading and necrotic lesions extending deeper into the hoof and soft tissues.
Deteriorating or flagged cows – these could be cows going from mobility score 2 to 3 or cows that seem in pain and are struggling or worsening. This category might include cows looking uncomfortable on a block or cows with blocks rocking up at the toe.
Pre-dry foot checks – this is one of the most important routine trims as it will protect the cow during one of the highest risk periods, i.e. periparturient period. These should be timed to fall around eight weeks before calving and most practically done 3–10 days before dry off. Pre-dry checks should not be done on the day of dry off (as this is a mastitis risk) and not within four weeks of calving to minimise the risk of stillbirth. If dry cows are blocked, they should have a block that wears away (wood or biodegradable blocks) as blocks on dry cows can get missed. As time before calving extends, the benefit to foot health at calving diminishes, so frequency of routine trimming is worth some consideration to ensure the time to calving is not too far from 8 weeks.
High dependency cows – these are cows with pre-existing foot health problems. Cows that have been lame are at the most risk of future lameness episodes. They are best checked regularly at 70–90-day intervals.
Rechecks – asking trimmers to note the cows for recheck is very important. These are often recorded on trim sheets as ‘lesion score 3’ cows. They may have more severe or specific conditions or blocks, particularly the non-wearing synthetic plastic blocks.
- Foul – recheck 7–10 days
- Heel ulcer – recheck three weeks (as the block is often on the claw most prone to bruising and sole ulcers)
- Other blocks – recheck 4–6 weeks
Early lactation checks – the optimal timing is still unclear, although we tend to advise a pre-breeding check around 60 days in milk. At this time sole bruising may be prevalent and some sole overload, but before this has become irreparable or a sole ulcer. Evidence shows:
1. Mid-lactation trims have been shown to be beneficial.
2. Checks at 80 days in milk were beneficial to milk yield in lame heifers.
3. Foot checks in earlier lactation appear more beneficial to reducing prevalence in a survey.
Pre-calving heifers – Vet Sara Pedersen is currently researching this. For some herds there can be benefit to this, but in high-wear scenarios, trimming method has to be carefully adjusted to avoid increasing lameness risk (i.e. retaining plenty of sole depth and toe thickness; relying on modelling alone). Some degree of targeted trimming of heifers with long toes and poor foot angle would seem a practical compromise until the science is clear cut.
Overgrown feet – Cows with overgrown feet are often at a higher risk of lameness. They may have missed a footcheck or they are losing foot shape due to a problem.
Working bulls – these cows might benefit from foot checks four weeks prior to breeding season and at intervals during breeding. Some people apply thin plastic ‘slips’ or ‘thins’ to protect the soles.

Using software to help:

A list of cows that are mobility score 2 and 3 will include cows under treatment, recurrent lame and cows on the chronic or high dependency list. The cows on the mobility score 2 and 3 list need to be reviewed and then seen at the right time for them, not each time they are on the mobility score 2 and 3 list. To assist with this, there are some software options which classifies cows into new cases, repeat cases, etc. See:

University of Nottingham the Shinyapps tool (see Figure 1)
TotalVet has a matrix populated with a spreadsheet upload
VetImpress uses a very robust data collection approach
National Milk Records (NMR) provide a very quick and simple data entry portal via Herd Companion, and this also populates Interherd.

Nick Bell

Figure 1. Example of mobility score data presented on Nottingham University Shinyapps tool, available free for Mobility Mentors to use