Laying hen production responses to least cost rations formulated with stochastic programming or linear programming with a margin of safety.
An experiment with 480 DeKalb DK laying hens was conducted to study the effect of rations formulated with stochastic programming (STCH) or linear programming with a margin of safety (LPMS) over 12, 28-d periods. Rations were formulated to guarantee the requirement of methionine and lysine > or = 69%, in all rations, and Ca and P > or = either 69 or 90%. The four rations were: LPMS69 with Ca and P > or = 69%, LPMS90 with Ca and P > or = 90%, STCH69 with Ca and P > or = 69%, and STCH90 with Ca and P > or = 90%. Rations formulated with STCH were lower in cost than LPMS rations for respective probability levels. Costs per metric ton for LPMS69, LPMS90, STCH69, and STCH90 were $155.70, $157.71, $155.00, and $156.30, respectively. Compared to STCH rations, LPMS rations were overformulated in nutrients. There was no difference (P > .05) in performance for hen-housed egg production, hen-day egg production, feed per dozen eggs, mortality, egg weight, or eggshell percentage.
Department of Poultry Science, Pennsylvania State University, University Park 16802.
T L
TL
Cravener
W B
WB
Roush
T H
TH
D'Alfonso
D000818:Animals; D002645:Chickens / Q000502:physiology*; D003362:Cost-Benefit Analysis; D004531:Eggs / Q000592:standards; D005260:Female; D005526:Food, Formulated; D010058:Oviposition / Q000502:physiology*; D011382:Programming, Linear; D013269:Stochastic Processes