Forty sows (PIC Camborough 1050) from a single farm were randomly selected at 112 days of gestation to evaluate if gut bacteria transverse the blood system of the sow to deposit gut microbiota into colostrum for piglet gut inoculation via the entero-mammary pathway. Fourteen first-parity gilts and twenty third-parity sows were used for the study. At the time of farrowing, colostrum, fecal samples and blood samples were collected to evaluate the presence of bacteria in each sample. Colostrum and blood samples were processed via centrifugation to separate the immune cell fraction. Total deoxyribonucleic acid (DNA) was extracted from fecal, colostrum and white blood cell fractions. 16S ribosomal ribonucleic acid (rRNA) gene amplicon sequencing was conducted at the Iowa State University DNA Facility (Ames, IA) to further characterize the bacterial and archaeal taxa present within each sample. Data were analyzed using Mothur and using R v4.0.3 (R Core Team, 2020). The experimental unit was the sow. Tables were generated to demonstrate the relative abundances of bacteria and archaea present in each type of sample and also identify organisms differentially abundant between sample types. Firmicutes was the most abundant phylum in colostrum and fecal samples and Tenericutes had the greatest abundance in blood comparative to other phyla. Further evaluation of the classification of bacteria present demonstrated that a few genera of bacteria are present in all three samples. Clostridum_sensu_stricto 1 was present in high relative abundance in colostrum and in moderate abundance in the feces while also being present within the blood. Other genera present in all three sample types includes Ruminococcus and Mycoplasma. In conclusion, the data suggest that there are bacteria present in all three locations of the sow at the time of farrowing and that first parity sows have different microbial populations than third parity sows.

Objective: The purpose of this study was to survey the vitamin and mineral levels in various pig tissues at different phases of the life cycle. Materials and methods: Forty-eight healthy pigs of different stages of production were used for sampling of different tissues. Seven sows and a minimum of 10 animals from each phase of production (suckling, nursery, and finishing) were selected for sampling. A blood sample was collected via sterile venipuncture for serum vitamin and mineral analysis. After euthanasia, the diaphragm and liver were collected. Samples were submitted to the Iowa State University Veterinary Diagnostic Laboratory for analysis. Data were analyzed using SAS (version 9.4; SAS Institute Inc) and presented as minimum and maximum concentrations with standard error. The experimental unit was the animal. Results: Levels of vitamin A, vitamin E, copper, zinc, selenium, iron, and manganese were higher in liver tissues than in serum and diaphragm tissues. Diaphragm muscle had similar levels of phosphorus as the liver tissue. Serum had similar levels of calcium as the liver tissue. Implications: These data provide a sampling of vitamin and mineral levels present in tissues and serum of commercial pigs and suggests that vitamin and mineral levels differ between sampling sites.

The objective of this study was to investigate the effects of dietary metabolizable energy (ME) level and the ratio of linoleic acid:α-linolenic acid (LA:ALA) on the growth performance, lipid metabolism, circulatory and joint inflammatory status, and synovial fluid proteome of grow-finish pigs. A total of 224 pigs (BW = 41.5 ±6.1 kg; PIC Genus 337 ×1050, Hendersonville, TN) were randomly assigned to either a high (3.55 Mcal/kg; HE) or low (3.29 Mcal/kg; LE) ME dietary treatment with a high (23:1) or low (12:1) LA:ALA in a 2 × 2 factorial arrangement. Diets were fed across three 28-day phases. Pigs were housed either 4 barrows or 4 gilts per pen. Blood samples were collected on d 0, 21, 42, and 84. Synovial fluid was collected from the hock and carpus joints on d 0 and d 84. Liver and adipose tissue samples were collected on d 84. Data were analyzed as repeated measures using PROC MIXED (SAS 9.4) with pen as the experimental unit and energy level, essential fatty acid ratio, sex, phase, and their interactions as fixed effects. Compared to LE, HE increased d 28, d 56 and d 84 body weight (BW; P = 0.005). For the overall period, HE increased average daily gain (ADG) compared to LE (P < 0.001) and improved feed efficiency (P = 0.001), while LE increased feed intake compared to HE (P < 0.001). Gilts receiving diets with low LA:ALA had similar final BW to barrows receiving a low LA:ALA at d 28, d 56 and d 84 (P = 0.024), resulting from improved overall d 0–84 ADG compared to gilts receiving the high LA:ALA (P = 0.031). In the liver, HE decreased the mRNA abundance of acetyl CoA carboxylase (ACACA; P = 0.004), cluster of differentiation 36 (P = 0.034), and tended to decrease fatty acid synthase (FASN; P = 0.056). In adipose tissue, HE decreased ACACA (P = 0.001) and FASN (P = 0.017). Plasma inflammatory markers C-reactive protein (CRP) and tumor necrosis factor-α (TNFα) were reduced on d 84 compared to d 0 (P ≤ 0.014). In the hock and carpus synovial fluid, LE tended to reduce CRP and TNFα (P ≤ 0.096). Hock and carpus synovial fluid CRP were also reduced on d 84 compared to d 0 (P = 0.001). Age of the pig impacted serum and hock synovial fluid protein abundance, but not energy level, LA:ALA, or their interactions (P < 0.05). To conclude, the high and low LA:ALA ratios utilized in this study can be fed at varying energy levels without impacting growth. Additionally, LA:ALA ratios can differentially impact the growth of barrows and gilts.

The objective of this study was to investigate the effects of dietary linoleic acid level and the ratio of linoleic acid:linolenic acid (LA:ALA) on the growth performance, expression of genes associated with lipid metabolism and inflammatory status of grow-finish pigs. A total of 300 growing pigs (BW = 41.1 ±6.3 kg) were randomly assigned to either a high (30 g/kg; HLA) or low (15 g/kg; LLA) dietary linoleic acid level with a high (23:1; HR), moderate (13:1; MR) or low (4:1; LR) dietary LA:ALA in a 2 × 3 factorial design. Diets were fed across three 28-day phases and were balanced for dietary metabolizable energy. Pigs were housed 5 pigs per pen in single-sex pens. Blood samples were collected on d 0, 21, 42, and 84, and synovial fluid was collected from the hock joint on d 0 and 84 for inflammatory marker analysis. Data were analyzed as repeated measures using PROC MIXED (SAS 9.4) with initial body weight as a covariate, pen as the experimental unit, and LA level, LA:ALA, sex, phases, and their interactions as fixed effects. Compared to HLA, LLA pigs tended to have increased BW at d 56 and d 84 (P = 0.088). There was no effect of LA × LA:ALA for growth performance. For the overall d 0 – 84 growth period, pigs fed HR had increased ADG compared to MR, with pigs receiving LR performing intermediate of MR and HR. Gilts receiving HR diets had increased d 84 BW compared to gilts receiving the low and moderate LA:ALA (P = 0.006), which was a result of improved overall d 0 – 84 ADG compared to gilts receiving the MR diets (P = 0.023). Barrows fed LR had improved BW on d 56 compared to MR and HR and higher final BW compared to HR, with MR performing intermediately (P = 0.006). This was a result of greater d 0 – 84 ADG (P = 0.023). Overall, C-reactive protein (CRP), tumor necrosis factor-α(TNFα), and interleukin-6 (IL-6) were reduced in the plasma of pigs over time (P ≤ 0.037). Across all treatments, CRP and TNFαwere reduced in the hock and carpus synovial fluid on d 84 vs. d 0 (P ≤ 0.049). In conclusion, LA:ALA ratios utilized in this study can be fed at varying linoleic acid levels without impacting growth or inflammation. Additionally, LA:ALA ratios can differentially impact the growth of gilts and barrows.

Four hundred and eighty (PIC 337 X 1050, PIC Genus, Hendersonville, TN) pigs were used to evaluate a novel threonine source (ThrPro, CJ America – Bio, Fort Dodge, IA) for nursery pigs from approximately 7 to 20 kg body weight. After weaning, pigs were sorted by sex and fed a common diet for one week. Upon completion of the first week, pigs were sorted into randomized complete blocks, equalized by weight, within 16 replications. Pigs were allocated to one of three dietary treatments: positive control (POS) – standard ileal digestible threonine-to-lysine ratio (SID; Thr:Lys) 0.60, negative control (NEG) - SID Thr:Lys ≤ 0.46, and alternative threonine source (TEST) - SID Thr:Lys 0.60. The alternative threonine source included fermentative biomass and was assumed to contain 75% threonine and a digestibility coefficient of 100%, based on the manufacturer’s specifications. All other nutrients met or exceeded the NRC (2012) recommendations. Growth and intake data were analyzed as repeated measures with a compound symmetry covariance structure using the MIXED procedure in SAS 9.4 (SAS Institute Inc., Cary, NC) with pen as the experimental unit. Treatment, phase, the interaction between treatment and phase, and block were included as fixed effects in the model. Differences in total removals were tested using Fisher’s Exact Test of PROC FREQ. Results were considered significant at P ≤ 0.05 and considered a trend at P > 0.05 and P ≤ 0.10. During the first 14 days, pigs fed TEST had decreased gain-to-feed ratio (G:F; 0.77 vs. 0.80, P = 0.022) compared to POS and increased G:F (0.77 vs. 0.73, P < 0.001) compared to NEG. Over days 14 to 28, pigs fed TEST had similar G:F (0.71 vs. 0.70, P = 0.112) compared to POS, and increased G:F (0.71 vs. 0.63, P < 0.001) compared to NEG. Overall (d 0 to 28), pigs fed TEST had similar ADG (0.47 vs. 0.47 kg/d, P = 0.982) and G:F (0.76 vs. 0.74, P = 0.395) compared to POS, and increased ADG (0.47 vs. 0.43 kg/d, P < 0.001) and G:F (0.76 vs. 0.67, P < 0.001) compared to NEG. Average daily feed intake was not significantly different across treatments for the entirety of the study. In conclusion, the replacement of crystalline L-threonine with a novel threonine source resulted in similar growth performance in nursery pigs from approximately 7 to 20 kg.