Abstract Recent evidence suggests the use of feed additives in sow gestation diets may enhance piglet quality, specifically birth weight and within-litter variation, and improve piglet survival. The objective of this study was to evaluate two bioactive compounds, glucosamine or a phytogenic blend, in gestation diets on component traits of litter size and corresponding fetal and placental development during late gestation. Gilts were bred at USMARC using standard breeding protocols, weighed, and randomly assigned to one of three dietary treatments: 1) standard corn/soybean meal gestation diet (CONT, n = 25); 2) CONT + 3.75 g of glucosamine-HCL (GlcN, n = 25); and 3) CONT + 1.15 g of a proprietary phytogenic blend (PHYTO, n = 25). All gilts were hand fed 2.3 kg/d of mash treatment diets from day 14 of gestation until harvest. At ∼107 days of gestation, pregnant gilts (n = 57; 76% overall pregnancy rate, PR) were harvested, and reproductive tracts were removed. The tracts were processed immediately to evaluate component traits of litter size (i.e., ovulation rate OR, embryonic/fetal survival, and uterine capacity UC). All fetuses and placentas were weighed to determine average fetal/placental weights, weight variation, placental efficiency, and allometric growth rate. Data for PR was analyzed using PROC GLIMIXX with orthogonal contrasts for mean separation and included contemporary controls (CC) of general population gilts bred (n = 100) and farrowed (n = 66) during the trial. All component traits of litter size and fetal/placental data were analyzed using PROC MIXED (Table 1). Although PR across all treatments were not different (P = 0.11; 66.0 ± 4.7, 70.8 ± 9.3, 79.2 ± 8.3, and 91.7 ± 5.6%, for CC, CONT, GlcN, and PHYTO, respectively), orthogonal contrasts demonstrated increased PR between CC and PHYTO groups (P = 0.03) and a tendency (P = 0.08) for increased PR between the CONT and PHYTO, illustrating improved PR for PHYTO fed dams. No significant differences (P 0.10) in component traits of litter size or fetal/placental development were observed across the diets. However, there were numerical increases in UC for both GlcN and PHYTO compared to CONT (0.7 and 0.8 viable fetus increase, for GlcN and PHYTO, respectively). Although this study did not show significant differences in component traits of litter size or fetal/placental development, improved pregnancy rate and numerically increased viable fetuses, particularly in the PHYTO diet, without detrimental effects to fetal/placental development, supports expanding research using these bioactive compounds to further evaluate the effect on piglet quality and survival. The USDA is an EEO provider.
Miles et al. (Wed,) studied this question.