Smith R, Pegram R G, Burt S, Killorn K J, Oosterwijk G, Paterson A, Wilsmore A J
FAO/DANIDA Studies on the Economic Impact of Ticks in Zambia Project, Lusaka, Zambia.
Trop Anim Health Prod. 1991 May;23(2):103-5. doi: 10.1007/BF02361192.
Supplementation of lactating Sanga cows in central Zambia with low cost crop residues and urea-mineral licks resulted in significant increases in milk offtake (79%), total daily milk (86%), and daily liveweight gain of their calves (86%). At 1988 market prices the value of the additional milk (ZK54.00) and of liveweight of both cow and calf (ZK189.00) over the 13 weeks exceeded the estimated costs of inputs by ZK180.00.
