The level of inanition or imbalance in minerals which lead to pica may result in excessive consumption in a short time also leading to urea poisoning. This has been noticed in at least one case in Senegal. Precautions should be taken to avoid this problem of over-consumption in drought prone countries particularly towards the end of the dry season when feed is scarce. The block should be introduced progressively, and it should be clear that the block, as it is presently formulated, cannot constitute the only feed and a minimum of roughage is necessary.