Authors : Van Lunen , T. A. , D. J. A. Cole and E. E. Falshaw
Abstract: An experiment was conducted to examine the effects of growth rate, as controlled by dietary lysine/DE ratio (g/MJ) on calcium, phosphorus and magnesium accretion rates of boars, gilts and barrows from 25 to 90 kg live weight. Twelve pigs (4 of each sex) were assigned to each dietary treatment consisting of lysine/DE ratios from 0.4 to 1.4, in 0.2 g/MJ increments. Feed was provided at 90% of ad libitum and at 90 kg all pigs were slaughtered and the body composition of 2 pigs per sex per treatment was determined. Growth responses to lysine/DE ratios were similar for all sexes with maximum growth rates occurring at the 0.8 and 1.0 g lysine/ MJ DE. Ash, P and Mg accretion rates increased linearly (P<0.001) in response to ADG except for P accretion in barrows. Ca accretion increased with increasing ADG, but not in a significant linear manner. The results of this study indicate that mineral accretion is closely related to growth rate in pigs. Based on the response of mineral accretion to growth rate, factorial estimates of Ca, P and Mg requirements were developed. Estimated net daily requirements for Ca, P and Mg for pigs from 25 to 90 kg live weight were of the order of 12.0, 4.8 and 0.32 g d-1.
Van Lunen , T. A. , D. J. A. Cole and E. E. Falshaw , 2003. Effect of Nutritionally Controlled Growth Rate on Mineral Deposition Rates of Highly Selected Pigs. Journal of Animal and Veterinary Advances, 2: 110-115.