Factorial calculation of nutrient requirements in lactating queens

The energy, protein, calcium and phosphorus requirements of lactating queen s were estimated by using the factorial method. Requirement values for prot ein and energy were divided into requirements for maintenance and for milk production. For maintenance, existing data were used. For milk production,t he net requirements were calculated by summing the energy and protein losse s in milk; the gross requirements were then estimated taking into account t he utilization of metabolizable energy (ME) for milk production and the dig estibility of protein and its utilization for milk production. Net maintena nce requirements for calcium and phosphorus were calculated from endogenous fecal, renal and cutaneous losses. Losses in milk were added. For calculat ion of gross calcium and phosphorus requirements, utilization was estimated from true digestibility under suboptimal, but not extreme conditions. For queens with large litters at the peak of lactation, the following estimated requirements were derived (per kg body weight): 0.81 MJ ME, 14 g protein, 428 mg calcium and 303 mg phosphorus.