Evaluation of Dietary Calcium and Phosphorus for Reproducing Sows Housed in Total Confinement on Concrete or in Dirt Lots

Technique for the Determination of Bone Volume and Specific Gravity

“…The reason for not using this relatively simple and responsive measure more extensively is not clearly understood. In agreement with our findings, Miller et al (19647, Coalson et al (.1972) and Kornegay et al (1973) reported that specrfic gravity increased as the dietary level of CalP increased. However, to the contrary, Schroeder et al (1974) claimed that bone density was not significantly affected by increasins the dietarv CalP level.…”

“…Miller et ai. (1964) and Kornegay et al (1973), adopted the procedure of Brown et al (1951) for determining the specific gravity of chilled hog carcasses to determine the specific gravity of the femur, humerus and Sth rib of pigs. Barzel (1969) and Petito and Evans (1984) hydrated chilled and frozen femurs, respectively, of rats for 60 min before weighing them in air and water.…”

Effect of Level of Dietary Calcium-Phosphorus during Growth and Gestation on Calcium -Phosphorus Balance and Reproductive Performance of First Litter Sows

“…Nimmo et al (1981) reported lower bone peak force values and less bone strength per unit area for gilts that had been fed .65% Ca and .50% P. They also found that 30% of the gilts on the lower Ca-P treatments had to be removed from the trial because they were unable to stand, whereas the removal rate for the gilts given .975% Ca, .75% P was negligible. Kornegay et al (1973) reported similar farrowing and weaning performance and tissue parameters for sows fed either 10.3 g Ca and 11.0 g P or 15.5 g Ca and 15.0 g P daily for five reproductive cycles. The data presently available are inconsistent and inconclusive for a wide variety of response criteria that must be considered in the estimation of Ca-P requirements of gilts during gestation.…”

“…Birth weights were greater (P<.05) for pigs from sows given p-gest B during gestation than for those from sows on p-gest A (1.4 vs 1.3 kg). Kornegay et aL (1973) reported no differences in farrowing or weaning performance traits, except average weaning weight, between pigs from sows fed low Ca-P levels (10.3 g Ca and 11.0 g P) and pigs from sows fed high levels (15.5 g Ca and 15.0 g P). In this trial, weaning weight was higher for pigs from sows fed the lower Ca and P levels.…”

“…Also, although a p-grow • p-gest interaction (P<.05) was observed for preand postfarrowing gilt weights, the average lactation weight loss was 1.02 kg for the 42-day lactation period. Kornegay et al (1973) reported an 11.4 kg weight loss during five reproductive cycles of 42 days each, while Harmon et al (1975) noted a 17-kg weight loss over a 28-day lactation. Dietary Ca-P treatment during gestation and subsequent lactation appears to have little if any effect on sow weight loss during lactation.…”