Anil, S. S., Anil, L. and Deen, J.2005. Evaluation of patterns of removal and associations among culling because of lameness and sow productivity traits in swine breeding herds. Journal of American Veterinary Medical Association 226, 956-961.
Dagorn, J. and A. Aumaitre.1979. Sow culling: Reasons for and effect on productivity. Livestock Production Science 6, 167-177.
D’Allaire, S., Stein, T. E. and Leman, A. D.1987. Culling patterns in selected Minnesota swine breeding herds. Canadian Journal of Veterinary Research 51, 506-512.
Dial, G. D., Marsh, W. E., Polson, D. D. and Vaillancourt, J. P. 1992. Reproductive failure: Differential diagnosis. pp. 88-137. In:, Diseases of Swine, 7th ed.(Leman, A. L., Straw, B. E., Mengeling, W. L., D’Allaire, S. and Taylor, D. J. ed.) Iowa State University Press, Ames.
Dijkhuizen, A. A., Morris, R. S. and Morrow, M.1986. Economic optimization of culling strategies in swine breeding herds, using the “porkchop computer program.”Preventive Veterinary Medicine 4, 341-353