The "Family Rule" allows a manufacturer to have a product that is "nutritionally similar" to another product in the same "family" to adopt the latter's "complete and balanced" statement without itself undergoing any feeding tests. The "similar" food must be of the same processing type; contain the same moisture content; bear a statement of nutritional adequacy for the same or less demanding life stage as the lead product; contain a dry matter, metabolizable energy (ME) content within 7.5% of the lead product's dry matter; meet the same levels of crude protein, calcium, phosphorus, zinc, lysine, thiamine (and for cat foods, potassium and taurine) as the lead food; and meet or exceed the nutrient levels and ratios of the lead family product or the AAFCO nutrient profiles, whichever is lower. The label statement on the similar food can be the same as the lead product if the ME is substantiated by the 10-day ME feeding study.