Effect of increasing dietary energy density during late gestation and lactation on sow performance, piglet vitality, and lifetime growth of offspring

Network pharmacology analysis of the regulatory effects and mechanisms of ALAE on sow reproduction in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Reproductive ability of sows is a primary element influencing the development of pig farming. Herbal extracts of Angelica sinensis (Oliv.) Diels, Astragalus mongholicus Bunge, Eucommia ulmoides Oliv., and Polypodium glycyrrhiza D.C.Eaton showed effects on improvement of reproduction in sows.

AIMS OF THE STUDY

To investigate the mechanism of the treatment effects by a compound of these four Chinese herbs in a 1:1:1:1 ratio (ALAE) on endometriosis, endometritis, uterine adhesion, intrauterine growth retardation, pre-eclampsia, and its enhancement of reproductive efficiency in sows.

MATERIALS AND METHODS

Active components of ALAE were identified by using ultra-performance liquid chromatography-mass spectrometry analysis and network pharmacology. Then we used the results to construct a visualization network. Key targets and pathways of ALAE involved in sow reproduction improvement were validated in sow animals and porcine endometrial epithelial cells (PEECs).

RESULTS

A total of 62 active compounds were found in ALAE (41 in Polypodium glycyrrhiza D.C.Eaton, 5 in Astragalus mongholicus Bunge, 11 in Eucommia ulmoides Oliv., 5 in Angelica sinensis (Oliv.) Diels) with 563 disease-related targets (e.g. caspase-3, EGFR, IL-6) involved in EGFR tyrosine kinase inhibitor resistance, PI3K-AKT, and other signaling pathways. Molecular docking results indicated GC41 (glabridin), GC18 (medicarpin), EGFR and CCND1 are possible key components and target proteins related to reproductive improvement in sows. In PEECs, EGFR expression decreased at the mRNA and protein levels by three doses (160, 320, and 640 μg/mL) of ALAE. The phosphorylation of downstream pathway PI3K-AKT1 was enhanced. The expression of inflammatory factors (IL-6, IL-1β), ESR1 and caspase-3 decreased through multiple pathways. Additionally, the expression levels of an anti-inflammatory factor (IL-10), angiogenesis-related factors (MMP9, PIGF, PPARγ, IgG), and placental junction-related factors (CTNNB1, occludin, and claudin1) increased. Furthermore, the total born number of piglets, the number of live and healthy litters were significantly increased. The number of stillbirths decreased by ALAE treatment in sow animals.

CONCLUSIONS

Dministration of ALAE significantly increased the total number of piglets born, the numbers of live and healthy litters and decreased the number of stillbirths through improving placental structure, attenuating inflammatory response, modulating placental angiogenesis and growth factor receptors in sows. The improvement of reproductive ability may be related to activation of the EGFR-PI3K-AKT1 pathway in PEECs. Moreover, ALAE maybe involved in modulation of estrogen receptors, apoptotic factors, and cell cycle proteins.

Indicators of improved gestation housing of sows. Part II: Effects on physiological measures, reproductive performance and health of the offspring

Prenatal stress is the mechanism through which poor welfare of pregnant sows has detrimental effects on the health and resilience of their piglets. We compared two gestation housing systems (IMPROVED versus [conventional] CONTROL) in terms of sow stress and welfare indicators and sought to determine whether potential benefits to the sows would translate into improved offspring health. Sows were mixed into 12 stable groups (six groups per treatment, 20 sows per group) 29 days post-service in pens with free-access, full-length individual feeding/lying-stalls. CONTROL pens had fully slatted concrete floors, with two blocks of wood and two chains suspended in the group area. IMPROVED pens were the same but with rubber mats and manila rope in each stall, and straw provided in three racks in the group area. Saliva was collected from each sow on day 80 of pregnancy and analysed for haptoglobin. Hair cortisol was measured in late gestation. Sows' right and left eyes were scored for tear staining in mid lactation and at weaning. Numbers of piglets born alive, dead, mummified, and total born were recorded. Piglets were weighed and scored for vitality and intra-uterine growth restriction (IUGR) at birth. Presence of diarrhoea in farrowing pens was scored every second day throughout the suckling period. IMPROVED sows had lower haptoglobin levels and tear-stain scores during lactation. IMPROVED sows produced fewer mummified piglets, and these had significantly lower IUGR scores, and scored lower for diarrhoea than piglets of CONTROL sows. Hence, improving sow welfare during gestation improved the health and performance of their offspring.

Membrane filtration processing of infant milk formula alters protein digestion in young pigs

Reducing heat treatment (HT) during processing of infant milk formula (IMF) is desirable to produce a product that more closely resembles breast milk. By employing membrane filtration (MEM), we produced an IMF (60:40 whey to casein ratio) at pilot scale (250 kg). MEM-IMF had a significantly higher content of native whey (59.9 %) compared to HT-IMF (4.5 %) (p < 0.001). Pigs, at 28 days old, were blocked by sex, weight and litter origin and assigned to one of two treatments (n = 14/treatment): (1) starter diet containing 35 % of HT-IMF powder or (2) starter diet containing 35 % of MEM-IMF powder for 28 days. Body weight and feed intake were recorded weekly. Pigs at day 28 post weaning were sacrificed 180 min after their final feeding, for the collection of gastric, duodenal, jejunum and ileal contents (n = 10/treatment). MEM-IMF diet resulted in more water-soluble proteins and higher levels of protein hydrolysis in the digesta at various gut locations compared to HT-IMF (p < 0.05). In the jejunal digesta, a higher concentration of free amino acids were present post MEM-IMF consumption (247 ± 15 µmol g^-1 of protein in digesta) compared to HT-IMF (205 ± 21 µmol g^-1 of protein). Overall, average daily weight gain, average dairy feed intake and feed conversion efficiency were similar for pigs fed either MEM-IMF or HT-IMF diets, but differences and trends to difference of these indicators were determined in particular intervention periods. In conclusion, reducing heat treatment during processing of IMF influenced protein digestion and revealed minor effects on growth parameters providing in vivo evidence that babies who are fed with IMF processed by MEM are likely to have different protein digestion kinetics but minimal effect on overall growth trajectories as babies fed IMF processed by traditional thermal processing.

Impact of dietary fat levels and fatty acid composition on milk fat synthesis in sows at peak lactation

BACKGROUND

Dietary fat is important for energy provision and immune function of lactating sows and their progeny. However, knowledge on the impact of fat on mammary transcription of lipogenic genes, de novo fat synthesis, and milk fatty acid (FA) output is sparse in sows. This study aimed to evaluate impacts of dietary fat levels and FA composition on these traits in sows. Forty second-parity sows (Danish Landrace × Yorkshire) were assigned to 1 of 5 dietary treatments from d 108 of gestation until weaning (d 28 of lactation): low-fat control diet (3% added animal fat); or 1 of 4 high-fat diets with 8% added fat: coconut oil (CO), fish oil (FO), sunflower oil (SO), or 4% octanoic acid plus 4% FO (OFO). Three approaches were taken to estimate de novo milk fat synthesis from glucose and body fat.

RESULTS

Daily intake of FA was lowest in low-fat sows within fat levels (P < 0.01) and in OFO and FO sows within high-fat diets (P < 0.01). Daily milk outputs of fat, FA, energy, and FA-derived carbon reflected to a large extent the intake of those. On average, estimates for de novo fat synthesis were 82 or 194 g/d from glucose according to method 1 or 2 and 255 g de novo + mobilized FA/d according to method 3. The low-fat diet increased mammary FAS expression (P < 0.05) and de novo fat synthesis (method 1; P = 0.13) within fat levels. The OFO diet increased de novo fat synthesis (method 1; P < 0.05) and numerically upregulated mammary FAS expression compared to the other high-fat diets. Across diets, a daily intake of 440 g digestible FA minimized milk fat originating from glucose and mobilized body fat.

CONCLUSIONS

Sows fed diets with low-fat or octanoic acid, through upregulating FAS expression, increased mammary de novo fat synthesis whereas the milk FA output remained low in sows fed the low-fat diet or high-fat OFO or FO diets, indicating that dietary FA intake, dietary fat level, and body fat mobilization in concert determine de novo fat synthesis, amount and profiles of FA in milk.

Effect of a multicarbohydrase containing α-galactosidase in sow lactating diets with varying energy density

Sow productivity improvements are associated with high energetic demand due to increasing prolificity. The reproductive life and longevity of sows, and the readiness for weaning of the offspring may be impaired when sows loose significant body weight (BW) during lactation. The impact of a multicarbohydrase containing α-galactosidase on a low energy dense lactation diet was evaluated in this study. Two-hundred and eight sows (208 ± 25.2 kg) were blocked by parity and BW to one of four treatments, in which a corn-soybean meal diet was formulated to have varying levels of added fat (0, 1.5%, and 3%) to titrate an energy density model. A fourth treatment replicated the 0% added fat formulation with enzyme supplementation at 250 g/tonne. Sows were weighed individually on entry, post-farrow (by calculation) and at weaning. Daily feed intakes (ADFI) and caloric intake were used for calculation of sow feed efficiency (FE) and caloric efficiency. Litter performance was characterized at birth, and size was standardized within 24h of farrow and within treatment to ensure uniform litter sizes. Average wean weight and pre-weaning mortality were determined. Piglets were weighted individually to study litter weight distribution. Data was analyzed as a randomized completely block design, using sow as the experimental unit, treatment as the main effect, and standardized average weight and litter sizes as covariates where appropriate. Although sows fed a multicarbohydrase had lower standardized litter size (P < 0.001), average wean weight was higher in this group and equivalent to the 3% added fat treatment. Enzyme supplementation tended to reduce the proportion of light weight pigs (BW < 4.1kg) within the litter, when compared with the 0% added fat diet (P < 0.1). The multicarbohydrase tended to increased sow ADFI (P < 0.10), although sows from all treatments had equivalent caloric intakes during lactation (P > 0.1). Enzyme supplementation yielded significant improvements in sow FE (P < 0.01), similar to the 3% added fat group. Thus, the carbohydrase degrading enzyme tested in this study improved the efficiency of sows, while increasing average wean weights of the offspring, suggesting an improvement in nutrient digestion and/or metabolic efficiency from typical lactation diets.

Effects of dietary supplementation of gestating sows with adenosine 5 '-monophosphate or adenosine on placental angiogenesis and vitality of their offspring

Our previous study found that dietary nucleotide supplementation, including adenosine 5 '-monophosphate (AMP), could increase AMP content in sow milk and promote piglet growth, but its effects on placental efficiency and piglet vitality remains unknown. This experiment aimed to investigate the effects of dietary AMP or its metabolite adenosine (ADO) supplementation on sow reproductive performance and placental angiogenesis. A total of 135 sows with a similar farrowing time were blocked by backfat and body weight (BW) at day 65 of gestation, and assigned to 1 of 3 dietary treatment groups (n = 45 per treatment): basal diet, basal diet supplemented with 0.1% AMP, or 0.1% ADO, respectively. Placental analysis and the characteristics of sows and piglets unveiled that compared with control (CON) group, AMP or ADO supplementation could improve sow placental efficiency (P<0.05) and newborn piglet vitality (P<0.05), increase piglet birth weight (P<0.05), and reduce stillbirth rate (P<0.05). More importantly, AMP or ADO supplementation could increase the contents of AMP, ADO, and their metabolites in placentae (P<0.05). Meanwhile, AMP or ADO supplementation could also increase placental vascular density (P<0.05) and the expression of vascular endothelial growth factor A (P<0.05), as well as promote the migration and tube formation of porcine iliac artery endothelial cells (P<0.05). Overall, maternal dietary AMP or ADO supplementation could increase their contents in the placenta, thereby improving placental angiogenesis and neonatal piglet vitality.

The Impact of Enhancing Diet Quality or Dietary Supplementation of Flavor and Multi-Enzymes on Primiparous Lactating Sows

This study was aimed to explore how a high-quality diet or a flavor plus multi-enzyme diet affects the feed intake, nutrient digestibility and antioxidation capacity of lactating sows and the growth of their progeny. Thirty primiparous sows were randomly assigned to three treatments from d 2 of lactation until weaning (d 21): control (CON), with a basal diet; high quality (HQ), with 200 kcal/kg higher net energy than CON; or the CON diet supplemented with 500 mg/kg flavor and 100 mg/kg multi-enzymes (F + E). Sows fed with the HQ or F + E diets improved piglets’ live weight (p < 0.05) and average daily weight gain (p < 0.10), litter weight gain (p < 0.10) and piglet growth to milk yield ratio (p < 0.10). Compared with CON, the HQ and F + E groups increased the digestibility of ether extract, ash, neutral detergent fiber, crude fiber and phosphorus (p < 0.10), and the HQ group also increased dry matter, gross energy, crude protein, acid detergent fiber and energy intake (p < 0.05). Compared with CON, the F + E group decreased serum urea nitrogen and aspartate aminotransferase (p < 0.05) and enhanced superoxide dismutase, catalase and glutathione peroxidase, but it decreased malondialdehyde in milk supernatant (p < 0.05).

The Impact of Maternal and Piglet Low Protein Diet and Their Interaction on the Porcine Liver Transcriptome around the Time of Weaning

Maternal diet during early gestation affects offspring phenotype, but it is unclear whether maternal diet during late gestation influences piglet metabolism. We evaluated the impact of two dietary protein levels in sow late gestation diet and piglet nursery diet on piglet metabolism. Diets met or exceeded the crude protein and amino acid requirements. Sows received either 12% (Lower, L) or 17% (Higher, H) crude protein (CP) during the last five weeks of gestation, and piglets received 16.5% (L) or 21% (H) CP from weaning at age 3.5 weeks. This resulted in a 2 × 2 factorial design with four sow/piglet diet treatment groups: HH and LL (match), HL and LH (mismatch). Piglet hepatic tissues were sampled and differentially expressed genes (DEGs) were determined by RNA sequencing. At age 4.5 weeks, 25 genes were downregulated and 22 genes were upregulated in the mismatch compared to match groups. Several genes involved in catabolic pathways were upregulated in the mismatch compared to match groups, as were genes involved in lipid metabolism and inflammation. The results show a distinct interaction effect between maternal and nursery diets, implying that sow late gestation diet could be used to optimize piglet metabolism.

In-Feed Supplementation of Resin Acid-Enriched Composition Modulates Gut Microbiota, Improves Growth Performance, and Reduces Post-Weaning Diarrhea and Gut Inflammation in Piglets

The weaning process represents a delicate phase for piglets, and is often characterized by lower feed intake, lower weight gain, diarrhea, and ultimately increased mortality. We aimed to determine the effects of RAC supplementation in diets on improving piglet growth and vitality, reducing post-weaning diarrhea, and enhancing gut health. In a 2 × 2 × 2 factorial experiment, we selected forty sows and their piglets. Piglets were followed until seven weeks of age. There were no significant differences found between RAC treated and control piglets until weaning (p = 0.26). However, three weeks after weaning, RAC treated piglets had higher body weight and average daily growth (ADG) than the control piglets (p = 0.003). In addition, the piglets that received RAC after weaning, irrespective of mother or prior creep feed treatment, had lower post-weaning diarrhea (PWD) and fecal myeloperoxidase (MPO) level than control piglets. Gut microbiota analysis in post-weaning piglets revealed that RAC supplementation significantly increased Lachnospiraceae_unclassified, Blautia, Butyricicoccus, Gemmiger and Holdemanella, and decreased Bacteroidales_unclassified. Overall, RAC supplementation to piglets modulated post-weaning gut microbiota, improved growth performance after weaning, reduced post-weaning diarrhea and reduced fecal myeloperoxidase levels. We therefore consider RAC to be a potential natural feed supplement to prevent enteric infections and improve growth performance in weaning piglets.

A Comparison of the Behavior, Physiology, and Offspring Resilience of Gestating Sows When Raised in a Group Housing System and Individual Stalls

Simple Summary

The housing patterns of gestating sows affect their health and welfare. In this study, the differences between behavior and stress hormone levels were assessed when sows were housed in a group housing system compared to individual stalls; in addition, the disease resistance and resilience of their piglets were compared. In our investigation, the group-housed sows showed more exploratory behavior, less vacuum chewing, less sitting behavior, and lower stress hormone levels throughout pregnancy. A lipopolysaccharide (LPS) injection test revealed that the offspring of group-housed sows showed better resistance and resilience to disease. Therefore, the gestating sows raised in a group housing system and their piglets are healthier and have improved welfare. Our results show that a group housing system provides higher welfare standards, with conditions that are more suitable for gestating sows in modern pig production.

Abstract

Being in a confined environment causes chronic stress in gestating sows, which is detrimental for sow health, welfare and, consequently, offspring physiology. This study assessed the health and welfare of gestating sows housed in a group housing system compared to individual gestation stalls. After pregnancy was confirmed, experimental sows were divided randomly into two groups: the group housing system (GS), with the electronic sow feeding (ESF) system; or individual stall (IS). The behavior of sows housed in the GS or IS was then compared; throughout pregnancy, GS sows displayed more exploratory behavior, less vacuum chewing, and less sitting behavior (p < 0.05). IS sows showed higher stress hormone levels than GS sows. In particular, at 41 days of gestation, the concentration of the adrenocorticotropic hormone (ACTH) and adrenaline (A) in IS sows was significantly higher than that of GS sows, and the A level of IS sows remained significantly higher at 71 days of gestation (p < 0.01). The lipopolysaccharide (LPS) test was carried out in the weaned piglets of the studied sows. Compared with the offspring of gestating sows housed in GS (PG) or IS (PS), PG experienced a shorter period of high temperature and showed a quicker return to the normal state (p < 0.05). Additionally, their lower levels of stress hormone (p < 0.01) suggest that PG did not suffer from as much stress as PS. These findings suggested that gestating sows housed in GS were more able to carry out their natural behaviors and, therefore, had lower levels of stress and improved welfare. In addition, PG also showed better disease resistance and resilience. These results will provide a research basis for the welfare and breeding of gestating sows.

Interaction of CP levels in maternal and nursery diets, and its effect on performance, protein digestibility, and serum urea levels in piglets

Reduced protein levels in nursery diets have been associated with a lower risk of postweaning diarrhea, but the interaction with CP levels in maternal diet on the performance of the offspring remains unclear. The objective of this study was to determine the effect of protein content in sow gestation and piglet nursery diets on the performance of the piglets until slaughter. This was studied in a 2 × 2 factorial trial (35 sows, 209 piglets), with higher or lower (H or L) dietary CP in sow diets (168 vs 122 g CP/kg) during late gestation. A standard lactation feed was provided for all sows (160 g CP/kg). For both sow treatments, half of the litters received a higher or lower CP in the piglet nursery diet (210 vs 166 g CP/kg). This resulted in four possible treatment combinations: HH, HL, LH and LL, with sow treatment as first and piglet treatment as second letter. For each phase, all diets were iso-energetic and had a similar level of essential amino acids. P_s*p is the p-value for the interaction effect between sow and piglet treatment. In the nursery phase (3.5-9 weeks of age), a tendency toward interaction between piglet and sow treatments with feed efficiency (P_s*p = 0.08) was observed with HH having the highest gain:feed ratio (G:F) (0.74 ± 0.01), LH the lowest (0.70 ± 0.01) and the other two groups intermediate. In the growing-finishing phase, an interaction was observed between the piglet and sow diets with decreased G:F for LH (P_s*p = 0.04) and a tendency toward interaction with increased daily feed intake for LH (P_s*p = 0.07). The sow diet showed a tendency toward a long-lasting effect on the dressing percentage and meat thickness of the offspring, which was higher for the progeny of H sows (P_s < 0.01 and P_s = 0.02, respectively). At 23 weeks, serum urea concentrations tended to be lower for the HH and LL groups (P_s*p = 0.07). Fecal consistency scores were higher at day 10-day 14 after weaning for piglets from L sows (P_s = 0.03 and P_s < 0.01, respectively). At day 7 after weaning, fecal consistency score was higher for piglets fed the higher protein diet (P_p < 0.01). At 8 weeks of age, the apparent total tract digestibility of CP (ATTD_CP) interacted between piglet and sow diet (P_s*p = 0.02), with HH showing the highest digestibility values. In conclusion, the protein levels in sow late-gestation and piglet nursery diets interacted with feed efficiency, ATTD_CP and serum urea concentrations in the nursery phase.

Effects of L-Arginine Supplementation during Late Gestation on Reproductive Performance, Piglet Uniformity, Blood Profiles, and Milk Composition in High Prolific Sows

This study was conducted to evaluate the effects of L-arginine supplementation levels during late gestation on reproductive performance and piglet uniformity in high prolific sows. A total of 60 F1 multiparous sows (Yorkshire × Landrace), with an average body weight of 238.2 kg, were allotted to one of three treatment groups in a completely randomized design. The dietary treatments were divided by the supplementation level of arginine during the late-gestation period, from day 70 to farrowing, as follows-(1) CON: corn-soybean meal-based basal diet (Arg 0.72%), (2) Arg10: basal diet + L-Arg 0.28% (Arg 1.0%), and (3) Arg15: basal diet + L-Arg 0.79% (Arg 1.5%). The same lactation diet was provided ad libitum to sows during the lactation period. There were no significant differences in body weight and backfat thickness in sows during late-gestation and lactation. Dietary arginine levels had no significant influences on the number of total born, stillbirth, and born alive. However, increasing inclusion level of L-arginine supplementation tended to increase (p < 0.10) alive litter weight linearly, and also linearly increased (p < 0.05) the piglet weight gain and litter weight gain during the lactation period. In piglet uniformity, the standard deviation of piglet birth weight (p < 0.05) and the coefficient of variation for piglet birth weight (p < 0.10) increased linearly, as dietary arginine levels increased in the late gestation period. Increasing L-arginine supplementation to late gestating sows linearly increased (p < 0.05) the blood concentrations of arginine and ornithine at day 90 and day 110 of gestation. On the other hand, dietary arginine levels in late gestation did not affect the blood parameters related to the nitrogen utilization. Increasing dietary arginine levels for the late gestating sows did not affect the milk composition for colostrum and milk at day 21 of lactation. In conclusion, the inclusion level of arginine in the diet for late gestating sows, by up to 1.5%, could improve the alive litter weight at birth and litter weight gain during lactation, whereas the piglet uniformity at birth was decreased due to the increase of survival for fetuses with light birth weight.

Placentae for Low Birth Weight Piglets Are Vulnerable to Oxidative Stress, Mitochondrial Dysfunction, and Impaired Angiogenesis

Intrauterine growth restriction (IUGR) is associated with fetal mortality and morbidity. One of the most common causes of IUGR is placental insufficiency, including placental vascular defects, and mitochondrial dysfunction. In addition, a high level of oxidative stress induces placental vascular lesions. Here, we evaluated the oxidative stress status, mitochondrial function, angiogenesis, and nutrient transporters in placentae of piglets with different birth weights: <500 g (L), 500-600 g (LM), 600-700 g (M), and >700 g (H). Results showed that placentae from the L group had higher oxidative damage, lower adenosine triphosphate and citrate synthase levels, and lower vascular density, compared to those from the other groups. Protein expression of angiogenic markers, including vascular endothelial cadherin, vascular endothelial growth factor A, and platelet endothelial cell adhesion molecule-1, was the lowest in the L group placentae compared to the other groups. In addition, the protein levels of glucose transporters GLUT1 and GLUT3 were downregulated in the L group, compared to the other groups. Furthermore, oxidative stress induced by H2O2 inhibited tube formation and migration in porcine vascular endothelial cells. Collectively, placentae for lower birth weight neonates are vulnerable to oxidative damage, mitochondrial dysfunction, and impaired angiogenesis.

Effect of dietary L-carnitine supplementation to sows during gestation and/or lactation on sow productivity, muscle maturation and lifetime growth in progeny from large litters

Genetic selection for increased sow prolificacy has resulted in decreased mean piglet birth-weight. This study aimed to investigate the effect of L-carnitine (CAR) supplementation to sows during gestation and/or lactation on sow productivity, semitendinosus muscle (STM) maturity, and lifetime growth in progeny. Sixty-four sows were randomly assigned to one of four dietary treatments at breeding until weaning; CONTROL (0mg CAR/d), GEST (125mg CAR/d during gestation), LACT (250mg CAR/d during lactation), and BOTH (125mg CAR/d during gestation & 250mg CAR/d during lactation). The total number of piglets born per litter was greater for sows supplemented with CAR during gestation (17.3 v 15.8 ± 0.52; P<0.05). Piglet birth-weight (total and live) was unaffected by sow treatment (P>0.05). Total myofibre number (P=0.08) and the expression level of selected myosin heavy chain genes in the STM (P<0.05) was greater in piglets of sows supplemented with CAR during gestation. Pigs from sows supplemented with CAR during gestation had lighter carcasses at slaughter than pigs from non-supplemented sows during gestation (83.8 v 86.7 ± 0.86kg; P<0.05). In conclusion, CAR supplementation during gestation increased litter size at birth without compromising piglet birth-weight. Results also showed that the STM of piglets born to sows supplemented with CAR during gestation was more developed at birth. However, carcass weight at slaughter was reduced in progeny of sows supplemented with CAR during gestation. The CAR supplementation strategy applied during gestation in this study could be utilized by commercial pork producers to increase sow litter size and improve offspring muscle development.