Complex sentence: There is a high frequency of skeletal problems in broilers, mainly in the locomotory system, including varus and valgus deformities, osteodystrophy, dyschondroplasia and femoral head necrosis.
Split into simpler sentences: There is a high frequency of skeletal problems in broilers, mainly in the locomotory system. Leg problems included varus and valgus deformities, osteodystrophy, dyschondroplasia and femoral head necrosis.