Poor grass growth and cold wet weather has left a lot to be desired when it comes to lamb performance, with grass quality having a major impact on lamb daily live weight gain. It is imperative that with lambs being finished through grass based systems we pay close attention not only to energy and protein requirements, but also trace element and mineral deficiencies. These can have major implications on feed conversion rates, and therefore time to finish. Control of internal parasites remains a priority, but it must be remembered that lambs carrying worm burdens are often concurrently suffering from trace element deficiency due to gut damage. Faecal egg counts for parasite burden and blood sampling to determine trace element deficiencies are two easily available diagnostic tests that allow better selection of both worm products and the best method of trace element supplementation. By Patrick Grant BVMS MRCVS Parklands Veterinary Group.