Effects of negative dietary cation-anion difference and calcidiol supplementation in transition diets fed to sows on piglet survival, piglet weight, and sow metabolism.

Diets that provide a negative dietary anion cation difference (DCAD) and supplement with a vitamin D metabolite 25-OH-D3 (calcidiol) may increase calcium availability at parturition, and enhance piglet survival and performance. This factorial study assessed the effects of DCAD, calcidiol (50 µg/kg), and parity (parity 1 or >1) and their interactions. Large White and Landrace sows (n = 328), parity 1 to 8 were randomly allocated in blocks to treatment diets from day 103 of gestation until day 3 postfarrow: 1) negative DCAD without calcidiol (negative DCAD + no CA), n = 84, 2) negative DCAD with calcidiol (negative DCAD + CA) n = 84, 3) positive DCAD without calcidiol (negative DCAD + no CA), n = 81, and 4) positive DCAD with calcidiol (positive DCAD + CA), n = 79. Negative DCAD diets were acidified with an anionic feed (2 kg/t) and magnesium sulfate (2 kg/t). All treatment diets contained cholecalciferol at 1,000 IU/kg. Dry sow diets contained 14.8% crude protein (CP), 5.4% crude fiber (CF), 0.8% Ca, and 83 mEq/kg DCAD. Treatment diets 1 and 2 contained 17.5% CP, 7.3% CF, 0.8% Ca, and -2 mEq/kg DCAD. Treatment diets 3 and 4 contained 17.4% CP, 7.4% CF, 0.8% Ca, and 68 mEq/kg DCAD. Before farrowing, all negative DCAD sows had lower urine pH than all sows fed a positive DCAD (5.66 ± 0.05 and 6.29 ± 0.05, respectively; P < 0.01); urinary pH was acidified for both DCAD treatments indicating metabolic acidification. The percentage of sows with stillborn piglets was not affected by DCAD, calcidiol, or parity alone but sows fed the negative DCAD + CA diet had a 28% reduction in odds of stillbirth compared to the negative DCAD + no CA diet and even lesser odds to the positive DCAD + CA diet. At day 1 after farrowing, blood gas, and mineral and metabolite concentrations were consistent with feeding a negative DCAD diet and that negative DCAD diets influence energy metabolism, as indicated by increased glucose, cholesterol, and osteocalcin concentrations and reduced nonesterified free fatty acids and 3-hydroxybutyrate concentrations. In the subsequent litter, total piglets born and born alive (14.7 ± 0.3 and 13.8 ± 0.3 piglets, respectively; P = 0.029) was greater for positive DCAD diets compared to negative DCAD diets; and there was an interaction between DCAD, calcidiol, and parity (P = 0.002). Feeding a negative DCAD diet influenced stillbirth, subsequent litter size, and metabolic responses at farrowing. More studies are needed to define optimal diets prefarrowing for sows.

The transition period between late gestation and lactation is critical to farrowing and successful lactation; sows with higher blood calcium have less risk of dystocia. We evaluated transition diets that provided a negative dietary cation­anion difference (DCAD) and supplemented with calcidiol (CA), both of which influence calcium metabolism. Purebred Landrace or Large White sows (n = 328) were enrolled in the experiment and selected sows that were either primiparous (n = 99) or multiparous (n = 229; average parity = 2.59 ± 1.51; parity range = 1 to 8) were fed a dry sow ration until day 103 of gestation and were then fed transition diets until day 3 postfarrowing in a factorial study. The diets were formulated to include 1) negative DCAD + no CA, 2) negative DCAD + CA, 3) positive DCAD + no CA, or 4) positive DCAD + CA. All diets induced a metabolic acidosis as indicated by urinary pH. Sows fed the negative DCAD with added calcidiol had a >28% reduction in odds of stillbirth over negative DCAD + no CA and positive DCAD + CA diets. Following weaning and re-mating, there were 0.9 more piglets born in the subsequent litter for both positive DCAD diets compared to negative DCAD diets. Blood gas, and mineral and metabolite concentrations provided evidence that negative DCAD diets positively influenced energy metabolism.

Data on the effects of the anionic protein meal BioChlorⓇ on sows before and after farrowing.

Three hundred and two parity 3 and 4 sows were allocated to one of three treatment groups: A (n=106): Control group fed the standard lactation diet; B (n=94): Lactation diet supplemented with 10 kg BioChlor/T; C (n=102): Lactation diet supplemented with 20 kg BioChlor/T. The sows were randomly allocated to treatment on entry to the farrowing shed at 100 d of gestation. The numbers allocated to each treatment were not equal with fewer sows allocated to treatment B at the start of treatment feeding than originally intended. Six allocated sows were not pregnant at their due farrowing date and two control group sows died after treatment feeding commenced prior to farrowing. All sows were individually housed in sow stalls and were fed 3 kg of their treatment diet once a day from d 105 of gestation. At d 110 of gestation, sows were moved into farrowing crates and continued to be fed 3 kg of their treatment diet once a day until the day of farrowing followed by ad libitum feeding of the treatment diet during a 27-d lactation. Approximately 50 litters from each treatment were randomly weighed to determine treatment effects on piglet average daily gain from birth to weaning. Litters were standardized within treatment to 10 piglets per litter at d 3 of lactation by allocating piglets from sows within treatment that had more than 12 piglets. After weaning, all sows were transported to a commercial module and mated on the first display of estrus. Sows were offered a common boar shed diet (13.8 MJ DE/kg; 170 g protein/kg; 9 g lysine/kg) ad libitum from weaning to mating. Following mating, all animals were fed 2.5 kg of a gestation diet (13.0 MJ DE/kg; 125 g protein/kg; 6 g lysine/kg) until farrowing. All sows were stalled individually during the gestation period following treatment feeding. Measures included: date of birth, number of piglets stillborn, number of piglets born alive, total number of piglets born, number of mummified feti, litter weight and number of piglets weighed at birth, litter weight and number of piglets at d 3, 14, and 26, number of piglets stillborn (gestation 2), number of piglets born alive (gestation 2), and total number of piglets born (gestation 2). The number of piglets born alive, number of total piglets born, and all weight measures were analyzed with mixed models with treatment as a fixed effect and sow within farrowing house as a random effect. A negative binomial model was used to estimate the incidence of still birth with sow within farrowing house as a random effect. For the odds of being re-mated a logistic regression mixed model was used to evaluate differences among treatment groups. These data provide information on an individual animal basis that can be used to inform pig producers, nutritionists, veterinarians, and researchers for further investigation on the use of anionic feeds in gestation diets of pigs and is suitable for future meta-analyses.