Performance Of Lactating Sows Research Articles

The Effect of Increased Standardized Ileal Digestible Lysine through Increased Soybean Meal During Late Gestation on Lactating Sow Performance

The Effect of Increased Standardized Ileal Digestible Lysine through Increased Soybean Meal During Late Gestation on Lactating Sow Performance

214 Effects of Fiber Concentration and Fermentation Rate on Reproductive Performance, Nutrient Digestibility, and Immune Response of Lactating Sows

Abstract High fiber diets are known to have many benefits to sows (e.g., improving reproductive performance such as vitality of piglets, stimulating gut health, and improving well-being), and due to their fermentation properties, they may have different functions in lactating sows. Fast fermentable fiber favors the growth of beneficial microbiota which contributes to improved gut health, and slow fermentable fiber increases the fecal mass and provides a delayed release of some nutrients which benefits the farrowing process of sows. On the other hand, high fiber diets may reduce feed intake and nutrient digestibility. The objective of this study was to investigate the effects of dietary fiber concentration and fermentation rate on lactating sow performance, nutrient digestibility, and immunity. Four diets were formulated with increasing fast fermentable fiber, with diets 1 and 2 formulated at low (15%) total dietary fiber (TDF) and diets 3 and 4 at high (25%) TDF. The proportion of fast fermentable fiber in total diet of 4 treatments were 1.25%, 2.5%, 3.75%, and 5% respectively. The main fiber sources were sugar beet pulp, oat hull, and barley. Digestible energy, crude protein, and lysine levels were comparable among each treatment group. A total of 136 lactating sows (Landrace × Large White) were blocked by parity, body weight (BW), and back fat (BF), and then randomly assigned to each block (8 blocks). Feed allowance was set to increase from 3 kg/d (primiparous) or 3.5 kg/d (multiparous) at farrowing to a maximum of 7 kg/d or 8 kg/d at 7d or 8d post farrowing. Results showed that sows in high fiber groups had an increased litter weight gain and BF loss (P < 0.05), and sows in fast fiber groups showed a decreased BW and protein loss (P < 0.05). Low fiber fed sows showed a significantly increased digestibility of protein, gross energy (GE), and dry matter compared with high fiber ones (P < 0.05). Sows fed with slow fermentable fiber in the low fiber groups showed greater digestibility of GE, protein, and dry matter compared with the ones fed with fast fermentable fiber; however, the opposite was true in high fiber groups. Fiber concentration and fermentation rate did not show significant effects on serum IL-8, IL-10, TNF-α, or endotoxin of sows (P > 0.05). In conclusion, high fiber diet increased BF loss and negatively influenced nutrient digestibility while having positive effects on litter growth. The negative effects of fiber were partially compensated by increasing the soluble fraction. Based on the current study, when feeding lactating sows a diet with high fiber, a relative increase of fast fermentable fiber is the most favorable feeding strategy.

Regulation of dietary fiber on intestinal microorganisms and its effects on animal health.

The animal gut harbors diverse microbes that play an essential role in the well-being of their host. Specific diets, such as those rich in dietary fiber, are vital in disease prevention and treatment because they affect intestinal flora and have a positive impact on the metabolism, immunity, and intestinal function of the host. Dietary fiber can provide energy to colonic epithelial cells, regulate the structure and metabolism of intestinal flora, promote the production of intestinal mucosa, stimulate intestinal motility, improve glycemic and lipid responses, and regulate the digestion and absorption of nutrients, which is mainly attributed to short-chain fatty acids (SCFA), which is the metabolite of dietary fiber. By binding with G protein-coupled receptors (including GPR41, GPR43 and GPR109A) and inhibiting the activity of histone deacetylases, SCFA regulate appetite and glucolipid metabolism, promote the function of the intestinal barrier, alleviate oxidative stress, suppress inflammation, and maintain immune system homeostasis. This paper reviews the physicochemical properties of dietary fiber, the interaction between dietary fiber and intestinal microorganisms, the role of dietary fiber in maintaining intestinal health, and the function of SCFA, the metabolite of dietary fiber, in inhibiting inflammation. Furthermore, we consider the effects of dietary fiber on the intestinal health of pigs, the reproduction and lactation performance of sows, and the growth performance and meat quality of pigs.

Maternal sodium acetate supplementation promotes lactation performance of sows and their offspring growth performance.

Milk yield and composition are critical determining factors for the early growth and development of neonates. The objective of this experiment was to comprehensively evaluate the effects of dietary sodium acetate (SA) supplementation on the milk yield and composition of sows and the growth performance of their offspring. A total of 80 sows (Landrace×Yorkshire, 3 to 6 parity) were randomly assigned to 2 groups (with or without 0.1% SA) from d 85 of gestation to d 21 of lactation. The result shows that maternal 0.1% SA supplementation significantly increased sows milk yield, milk fat, immunoglobulin A (IgA) and IgG content in milk (P<0.05), with the up-regulation of short-chain fatty acids receptors (GPR41 and GPR43) expression and the activation of mammalian target of rapamycin complex C1 (mTORC1) signaling pathway. Consistently, in our invitro experiment, SA also activated mTORC1 signaling in porcine mammary epithelial cells (P<0.05). Furthermore, the improvement of milk quality and quantity caused by maternal SA supplementation led to the increase in body weight (BW) and average daily weight gain (ADG) of weaning piglets, with the improvement of gut health and colonization of the beneficial bacteria (P<0.05). In conclusion, maternal supplementation of 0.1% SA improved the lactation performance (milk yield and milk fat) of sows, possibly with the activation of GPR41/GPR43-mTORC1 signaling. Furthermore, enhanced milk quality improved growth performance, gut health and the colonization of beneficial microbial flora of their piglets.

Evaluation of supplemental fat sources and pre-farrow essential fatty acid intake on lactating sow performance and essential fatty acid composition of colostrum, milk, and adipose tissue.

A total of 91 sows (Line 241, DNA Genetics) were used to evaluate the effects of supplemental fat sources and essential fatty acid intake on sow farrowing performance, litter growth performance, and essential fatty acid composition of colostrum, milk, and adipose tissue. At approximatelyday 107 of gestation, sows were blocked by body weight and parity, then allotted to 1 of 5 experimental treatments as part of a 2 × 2 + 1 factorial arrangement. Experimental diets were corn-soybean meal-based with a control diet that contained no added fat or diets with 3% added fat as either beef tallow or soybean oil, with consumption of the added fat diets starting on day 107 or 112 of gestation and fed until weaning. Thus, sows were provided low essential fatty acids (EFA; as linoleic and α-linolenic acid) without supplemental fat or with beef tallow or high EFA with soybean oil. Sows were provided approximately 2.8 kg/d of their assigned lactation diet pre-farrow and then provided ad libitum access after parturition. Sows consuming diets with beef tallow had greater lactation ADFI (fat source, P = 0.030), but lower daily linoleic acid (LA) and α-linolenic acid (ALA) intake than sows that consumed diets with soybean oil (fat source, P < 0.001). Supplemental fat sources providing either low or high EFA did not influence litter growth performance (fat source, P > 0.05). Sows fed diets with beef tallow did not influence the LA composition of colostrum; however, lactation diets with high EFA provided by soybean oil on day 107 of gestation increased colostrum LA concentration compared to providing diets on day 112 of gestation (fat source × time, P = 0.084; time, P < 0.001). Additionally, regardless of pre-farrow timing, ALA concentration of colostrum increased when sows consumed diets with soybean oil compared to beef tallow (fat source, P < 0.001). Both LA and ALA concentrations of milk at weaning were greater for sows that consumed diets with soybean oil compared to beef tallow (fat source, P < 0.001). Furthermore, concentrations of LA and ALA within adipose tissue were greater at weaning when sows consumed diets with high EFA compared to low EFA (fat source, P < 0.05). These responses suggest that providing dietary fat sources with high concentrations of EFA can increase backfat, colostrum, and milk LA and ALA. However, in this experiment, changes in colostrum and milk composition did not influence litter growth performance.

Dietary silymarin ameliorating reproductive and lactation performance of sows via regulating body antioxidant and metabolism

ObjectiveThe experiment was conducted to explore the effects of silymarin on reproductive and lactation performance, serum antioxidants, and body metabolism of sows. MethodsSixty pregnant sows (85 d, Large × Landrace) with similar genetic background, body condition, and parity were randomly divided into three groups, and each group has 20 individually housed sows. The sows in the control group (CG) were fed with basal diet, and those in the experimental group A (EGA) and B (EGB) were fed with basal diet containing 250 and 500 mg/kg silymarin, respectively. The experiment lasted 46 days from day 85 of gestation to the end of lactation (weaning on day 17 ).The milk composition and serum biochemical parameters were determined by a milk composition analyzer and a blood biochemical analyzer, respectively. Serum antioxidant indexes and plasma hormone levels were measured using the biochemical kits. The gas chromatograph was applied to detect the fecal short chain fatty acids. ResultsCompared with the CG, the total feed intake (TFI) and average daily feed intake (ADFI) were significantly increased (P < 0.01), and the urea content in regular milk tended to increase (P = 0.095) in the EG. The serum malondialdehyde (MDA) contents were decreased on day 90 of gestation and the day of farrowing (P < 0.01), and the serum contents of total antioxidant capacity (T-AOC) tended to increase on day 17 of lactation (P = 0.099) compared with the CG. Compared with the CG, the serum triglyceride (TG) concentrations in the EG tended to increase on day 90 of gestation (P = 0.062), and the content of serum total protein (TP) and albumin (ALB) reduced on day 17 of lactation (P < 0.01). Compared with the CG, plasm D-lactic acid content was decreased (P < 0.05), and the plasma prostaglandin (PG) level tended to increase (P = 0.088) in the EG on the day of farrowing and day 17 of lactation. Compared with the CG, fecal isobutyric acid concentration in the EG significantly decreased on the day of farrowing ( P < 0.05). ConclusionAdding 250 – 500 mg/kg silymarin to diets from the late gestation to the end of lactation could improve reproductive and lactation performance of sows via the regulation of nutrient metabolism and serum antioxidant.

509 Late-Breaking: Effect of a Sensory Additive on Sow Reproductive Performance

Abstract The addition of a sensory additive to sow diets during the summer improved feed intake during lactation, and litter performance. The aim of this study was to evaluate the impact of the sensory additive on sow lactation performance during cooler temperatures. Three consecutive groups (n = 61 total) of sows were farrowed during winter (October, December and January). Sows were weighed, and back fat depth was measured, at 110 d of gestation prior to entering the lactation room, and again at weaning. The sows were sorted by parity, and then allotted by BW at d 110 to Control or 0.075% sensory additive (Luctamax® SowVive, Lucta S.A., Spain). Experimental diets were offered upon entry to the lactation room and fed through weaning. Feed disappearance was recorded every three days. Sows were fed 2.72 kg/head/day until farrowing, and then allowed to eat ad libitum from 24 hours post-farrowing until weaning. Data were analyzed using the PROC MIXED procedure of SAS as an RCBD with treatment as the fixed effect and group as a random effect. No differences were observed on sows feed intake (P &amp;gt; 0.4), 10th rib backfat thickness change (P = 0.632) and body weight change from d 110 of gestation to weaning (P = 0.65, Table 1). Sows fed the sensory additive lowered preweaning mortality by 4.9% (P = 0.051), and weaned an additional 1.42 piglets (P = 0.026) with similar weaning weights (P = 0.86) when compared to control. In conclusion, in the current study, lactation diets supplemented with a sensory additive improved litter performance and helped maintain sow body condition.

Identification of SNPs and Candidate Genes for Milk Production Ability in Yorkshire Pigs.

Sow milk production ability is an important limiting factor impacting suboptimal growth and the survival of piglets. Through pig genetic improvement, litter sizes have been increased. Larger litters need more suckling mammary glands, which results in increased milk from the lactating sow. Hence, there is much significance to exploring sow lactation performance. For milk production ability, it is not practical to directly measure the milk yield, we used litter weight gain (LWG) throughout sow lactation as an indicator. In this study, we estimated the heritability of LWG, namely, 0.18 ± 0.07. We then performed a GWAS, and detected seven significant SNPs, namely, Sus scrofa Chromosome (SSC) 2: ASGA0010040 (p = 7.73E-11); SSC2:MARC0029355 (p = 1.30E-08), SSC6: WU_10.2_6_65751151 (p = 1.32E-10), SSC7: MARC0058875 (p = 4.99E-09), SSC10: WU_10.2_10_49571394 (p = 6.79E-08), SSC11: M1GA0014659 (p = 1.19E-07), and SSC15: MARC0042106 (p = 1.16E-07). We performed the distribution of phenotypes corresponding to the genotypes of seven significant SNPs and showed that ASGA0010040, MARC0029355, MARC0058875, WU_10.2_10_49571394, M1GA0014659, and MARC0042106 had extreme phenotypic values that corresponded to the homozygous genotypes, while the intermediate values corresponded to the heterozygous genotypes. We screened for flanking regions ± 200 kb nearby the seven significant SNPs, and identified 38 genes in total. Among them, 28 of the candidates were involved in lactose metabolism, colostrum immunity, milk protein, and milk fat by functional enrichment analysis. Through the combined analysis between 28 candidate genes and transcriptome data of the sow mammary gland, we found nine commons (ANO3, MUC15, DISP3, FBXO6, CLCN6, HLA-DRA, SLA-DRB1, SLA-DQB1, and SLA-DQA1). Furthermore, by comparing the chromosome positions of the candidate genes with the quantitative trait locus (QTLs) as previously reported, a total of 17 genes were found to be within 0.86–94.02 Mb of the reported QTLs for sow milk production ability, in which, NAV2 was found to be located with 0.86 Mb of the QTL region ssc2: 40936355. In conclusion, we identified seven significant SNPs located on SSC2, 6, 7, 10, 11, and 15, and propose 28 candidate genes for the ability to produce milk in Yorkshire pigs, 10 of which were key candidates.

Prolactin and the swine mammary gland

Prolactin is a hormone that is most important for mammary development in swine. It is also essential for both the onset and the maintenance of lactation. In early studies, exogenous recombinant porcine prolactin was used to detect its biological effects on mammary tissue. In these studies, a stimulatory role of prolactin for mammary development of prepubertal gilts was demonstrated. However, when injected throughout lactation, prolactin did not increase sow milk yield likely because mammary receptors were saturated. The secretion of prolactin is largely under negative regulation via dopamine. Inhibition studies using the dopamine agonist bromocriptine showed that prolactin is required in the last third of gestation to sustain mammary development in gilts. When creating a hyperprolactinemic state during that same period, with the dopamine antagonist domperidone, differentiation of mammary epithelial cells was stimulated and milk yield in the subsequent lactation was increased. Domperidone given throughout lactation also led to greater milk yield. A study using domperidone in prepubertal gilts, however, did not reproduce the stimulatory effect of exogenous prolactin on mammary development and demonstrated that timing of the prolactin increase in relation to age of the animals is most important to elicit a response on mammary tissue. Attempts were made to use feed ingredients such as the plant extract from milk thistle, sylimarin, to stimulate prolactin secretion in sows. However, even though prolactin concentrations were increased, this augmentation was not important enough to have an impact on mammary development in late gestation or to increase milk yield. The current knowledge that hyperprolactinemia has beneficial effects for mammary development at various physiological stages and can enhance milk yield in swine leads to new avenues in elaborating strategies that could be used at the farm level to improve sow lactation performance.

Providing domperidone throughout lactation enhances sow lactation performance.

The goal of this project was to determine the effects of domperidone given throughout lactation on hormonal and metabolic status, lactational performance, and gene expression in mammary epithelial cells of sows. Second parity sows were divided in two treatment groups: 1) daily intramuscular injections with canola oil (Control, CTL, n = 24), or 2) daily intramuscular injections with 0.5 mg/kg body weight (BW) of domperidone (DOMP, n = 23). Injections were given at 08h05 starting the day after farrowing until weaning. Over the first 4 d of treatment, DOMP sows also received 0.5 mg/kg BW of domperidone per os twice daily, whereas CTL sows were fed the vehicle. Litter size was standardized to 11 ± 1 within 24 h of birth and piglets were weighed at birth, 24 h postpartum, and on days 7, 22 (weaning on day 23), 35, and 56. Sow feed intake was recorded daily. Representative milk samples were obtained aseptically on day 21 of lactation from 15 sows per treatment for compositional analyses and milk fat globules were used to measure mRNA abundances of various genes. Jugular blood samples were obtained from all sows on days 2, 8, 16, and 23 of lactation to measure concentrations of prolactin, insulin-like growth factor-1 (IGF-1), leptin, adiponectin, insulin, glucose, urea, and free fatty acids (FFA). Concentrations of prolactin (P < 0.001) and FFA (P < 0.01) were increased in DOMP compared with CTL sows, whereas concentrations of insulin were decreased (P < 0.05). Urea concentrations were increased by treatment (P < 0.05) on days 16 and 23 of lactation, and those of IGF-1 were increased (P < 0.01) on day 16. Piglets from DOMP sows were heavier than those from CTL sows on day 22 (P < 0.01). Milk composition was unaffected by treatment. The mRNA abundance in milk fat globules for casein beta and whey acidic protein were lower (P ≤ 0.05) in DOMP than CTL sows. The long form of the prolactin receptor and the signal transducer and activator of transcription 5A mRNA abundances tended to be lower (P < 0.10) in DOMP than CTL sows. In conclusion, hyperprolactinemia induced by domperidone during lactation affected the endocrine and metabolite status of sows and stimulated growth of their suckling piglets.

PSIV-15 Influence of Particle Size of Enogen Feed Corn and Conventional Yellow Dent Corn on Lactating Sow Performance

Abstract A total of 107 sows (Line 241; DNA, Columbus, NE) across 4 batch farrowing groups were used to evaluate the effects of corn source and particle size on sow and litter performance. Treatments were arranged in a 2×2 factorial with main effects of corn source (Enogen® Feed corn (Syngenta Seeds, Downers Grove, IL) or conventional yellow dent corn) and ground corn particle size (600 or 900 µm). Sows were blocked by parity and BW upon arrival to the farrowing house. There were approximately 27 sows per treatment, sow was considered the experimental unit, dietary treatment was a fixed effect, and sow group and block were used as random effects. Main effects of corn source and particle size as well as their interactions were tested. From farrowing to weaning, there was a tendency for a source×particle size interaction (P=0.065) for sow BW change. Sows fed 900 µm Enogen Feed corn had decreased BW loss compared to sows fed other treatments which were similar in BW loss. There was a source×particle size interaction (P=0.048) for lactation ADFI with sows fed 900 µm conventional yellow dent corn having lower feed intake than the sows fed 600 µm conventional yellow dent corn, whereas sows fed 900 µm Enogen Feed corn had greater feed intake compared to the sows fed 600 µm Enogen Feed corn. There was a tendency for a particle size main effect (P&amp;lt;0.10) for litter ADG (2,849 vs 2,635 g/d) and total litter gain (45.7 vs 42.3 kg), with sows fed corn ground to 600 µm having increased litter ADG and total litter gain compared to sows fed corn ground to 900 µm. In summary, there were few differences in sow or litter characteristics among corn sources. Reducing particle size of both corn sources tended to increase litter ADG and weaning weights.

Evaluation of Supplemental Fat Sources and Pre-Farrow Essential Fatty Acid Intake on Lactating Sow Performance and Essential Fatty Acid Composition of Colostrum, Milk, and Adipose Tissue

Evaluation of Supplemental Fat Sources and Pre-Farrow Essential Fatty Acid Intake on Lactating Sow Performance and Essential Fatty Acid Composition of Colostrum, Milk, and Adipose Tissue

Effects of dietary supplementation of nucleotides from late gestation to lactation on the performance and oxidative stress status of sows and their offspring.

Increased metabolic burdens in breeding sows, which are induced by elevated systemic oxidative stress, could increase the need for nucleotides to repair lymphocyte DNA damage; however, de novo synthesis of nucleotides may be insufficient to cover this increased need. This study investigated the effects of dietary nucleotides on milk composition, oxidative stress status, and the reproductive and lactational performance of sows. Forty multiparous sows were assigned to 2 dietary treatments (Control group, and 1 g/kg Nucleotides group) based on a randomized complete block design using their BW at 85 d of gestation as a block. Sows from 2 groups were fed a restricted diet during gestation and ad libitum during lactation. The experiment lasted from 85 d of gestation to 21 d of lactation. The reproductive performance of sows and the growth performance of suckling piglets were measured. Oxidative stress parameters and milk components were also analysed. Data were analyzed using contrasts in the MIXED procedure of SAS. Sows in the Nucleotides group consumed more feed during the first week (P < 0.01) and from 1 to 21 d (P < 0.05) of lactation than those in Control group. Correspondingly, the litter weight gain of piglets showed a tendency to increase from cross-fostering to 9 d (P = 0.09) and from cross-fostering to 20 d (P = 0.10) in the Nucleotides group relative to the Control group. Additionally, the Nucleotides group was higher (P < 0.01) than the Control group in the concentrations of uridine 5'monophosphate, guanosine 5'monophosphate, inosine 5'monophosphate, adenosine 5'monophosphate and total nucleotides in milk. Furthermore, the Nucleotides group was higher (P < 0.01) than the Control group in the serum levels of total antioxidant capacity (P < 0.01) for sows at 109 d of gestation and glutathione peroxidase for weaning piglets, but lower at the levels of thiobarbituric acid-reactive substances (P < 0.05) in serum of weaning piglets. This study indicated that maternal dietary nucleotides could promote piglet growth, probably due to the higher lactational feed intake and higher concentration of nucleotides in the milk of sows, and lower oxidative stress for both sows and piglets.

270 Efficacy of Bacillus subtilis and Bacillus licheniformis (BioPlus2B®) on sow lactation performance, litter growth, nursery performance and health of pigs challenged with PRRS virus post-wean

Abstract Probiotics have been shown to support normal growth and immune function in pigs in challenging environments. A commercial probiotic (BioPlus2B®) containing two microbial species (Bacillus subtilis and Bacillus licheniformis) was tested to determine its effect on lactation of sows, pre-weaning performance of litters, and post-weaning performance of pigs challenged with PRRS virus. Sows (n = 120) were fed to meet or exceed NRC 2018 requirements and divided into two treatment groups: control and BioPlus2B®. BioPlus2B® was fed daily at an equivalent of 1.6 x 109CFU/kg and daily feed intake was recorded. Production practices were closely monitored in order to reduce the risk of bacteria cross-contamination between treatment groups and to maintain responsible animal welfare practices. By 24 hours post-farrow, piglets were cross-fostered within treatment group and subsequently weighed. They were weighed again on day 17. Upon weaning at approximately 21 days, piglets from each treatment group were separated into one of three BSL2 rooms and allocated to one of 36 pens per treatment for a 28-day growth study. The treatment group was fed BioPlus2B® daily at 1.1 x 109CFU/kg. At seven days post-wean, pigs were infected IM with 2 x 103.5 TCID 50 of the PRRS virus. Sow, litter, or pen was considered the experimental unit except for birth and wean weights. Sows that consumed BioPlus2B® daily birthed heavier piglets, consumed more feed throughout lactation, and tended to wean heavier pigs than Control sows. Pigs that consumed BioPlus2B® post-wean resulted in greater ADG, ADG:ADFI, and reduced mortality after PRRS infection. Data is expressed as least square means ±SEM. Values at P&amp;lt; 0.05 are considered significantly different while values between 0.05&amp;lt; P≤0.10 are considered a trend. In summary, feeding a defined probiotic supports optimal performance of sows and litters and effective immune responses of pigs challenged with respiratory disease.

272 Hybrid rye may replace up to 75% of the corn in diets for gestating and lactating sows without negatively impacting sow and piglet performance

Abstract An experiment was conducted to test the hypothesis that hybrid rye can replace corn in gestation and lactation diets without negatively affecting sow and litter performance. For gestation and lactation, a corn-soybean meal control diet and 3 additional diets in which hybrid rye replaced 25, 50, or 75% of corn were formulated. Sows were randomly allotted by parity to treatments, with 45 replicate sows per treatment. Sows were individually housed for the duration of the experiment. Sow BW were recorded on d 7 and d 105 of gestation, as well as within 24 h after farrowing and on the day of weaning (approximately d 20 of lactation). Number and weights of live born, still born, and mummified piglets were determined within 24 h of farrowing. Data related to piglet mortality were analyzed using SAS Proc Glimmix with binomial distribution, whereas all other data were analyzed using Proc Mixed. The statistical models included the fixed effects of diet and parity. Diet did not influence sow BW or sow ADG at any point in the experiment (Table 1). Diet did not affect number or weights of total, live, or still born pigs, but there was an increase and then a reduction in the number of pigs weaned, litter wean weight, and litter ADG as the inclusion of hybrid rye in the diets increased (quadratic, P &amp;lt; 0.05). Piglet mortality, as well as the proportion of piglets crushed by sows, tended (P &amp;lt; 0.10) to be quadratically reduced as hybrid rye was added to the diet. In conclusion, replacing corn with hybrid rye in gestation and lactation diets had no effect on sow BW changes nor on number or birthweights of piglets, and overall, diets with 25% and 50% corn replacement rate with rye resulted in improved sow lactation performance.

Long noncoding RNA and mRNA profiling of hypothalamic-pituitary-mammary gland axis in lactating sows under heat stress

Heat stress (HS) seriously affects sow lactation performance and Long non-coding RNAs (lncRNAs) play vital roles in the regulation of transcription and post transcription. However, the mechanism of lncRNAs expression affecting lactation performance on the hypothalamus-pituitary-mammary axis of sows is still unclear. In this study, we performed RNA sequencing and bioinformatics analysis of the hypothalamus, pituitary, and mammary gland tissues of lactating sows under HS and thermal comfort. In total, the analysis identified 658, 6021, and 6745 differently expressed (DE) mRNAs, 26, 126, and 169 DE lncRNAs between comparison groups in the hypothalamus, pituitary, and mammary glands, respectively. The hormone genes and most DE mRNAs encoding heat shock protein were differently expressed in the HS group. In addition, 2, 60, and 86 pairs of DE lncRNAs and mRNAs correlation were observed in those tissues, respectively. Some lncRNAs may be involved in the regulation of lactation performance in the HS sows.

Influence of Particle Size of Enogen Feed High Amylase and Conventional Yellow Dent Corn on Lactating Sow Performance

A total of 107 sows (Line; 241 DNA; Columbus, NE) were used in a study to evaluate the effect of Enogen Feed corn and conventional yellow dent corn ground to different particle sizes in lactation diets on sow and litter performance. On d 107 of gestation, sows were blocked by body weight and parity and allotted to 1 of 4 dietary treatments. Dietary treatments consisted of 2 corn sources (Enogen Feed corn and conventional yellow dent) and 2 ground corn particle sizes (600 and 900 microns). A common diet was fed to sows from time of arrival into the farrowing house until they farrowed. Once the sows farrowed, they were fed treatment diets until weaning. Litters were cross fostered across treatments until 48 h post farrowing to equalize litter size. Litters were weighed at birth, d 2, 7, 14, and weaning (d 21). Sow average daily feed intake (ADFI) was measured each time the litters were weighed. There was a tendency for a source × particle size interaction for weight change from farrow to wean (P = 0.065) with the sows fed the 900-micron high amylase corn diets losing less weight compared to sows fed the other diets. From farrow to weaning, there was a corn source × particle size interaction (P = 0.048) for ADFI, with sows fed the conventional corn ground to 900 microns having the lowest ADFI, and sows fed the conventional corn ground to 600 microns having the greatest intake. Litter average daily gain (ADG) and total litter gain tended to be greater (P < 0.10) for sows fed diets with 600-micron ground corn compared to the 900-micron ground corn. This is the first study, to our knowledge, that demonstrates the impact of Enogen Feed corn on sow and litter performance. Additional research conducted in a larger scale, commercial facility with more sows is warranted. In summary, there were few differences in sow or litter characteristics among those fed high amylose or conventional yellow dent corn. Sows fed 600-micron ground corn tended to have greater litter ADG and weaning weights, but individual pig weights were not different among treatments.

Role of Maternal Dietary Protein and Amino Acids on Fetal Programming, Early Neonatal Development, and Lactation in Swine.

Simple SummaryDietary protein is an important nutrient source for sows, necessary for not only growth and production, but also other physiological functions. Protein limitations in maternal diets have the potential to impair fetal myogenesis, while excess maternal dietary protein appears to only have minor effects on early fetal muscle formation. Effects of maternal protein deficiency on increased fat deposition in porcine neonates is inconsistent with gene expressions in the neonates. Sufficient maternal dietary protein can enhance porcine milk protein and fat concentration. Understanding the function of protein and amino acids in sows and the effects on their offspring can provide rational approaches for the regulation of piglet growth and further improvements in meat quality in the future.Maternal nutrition plays a vital role in fetal development, early development of neonates, and lactation and regulates the lifetime productivity of offspring. During pregnancy, maternal nutrition alters expression of the fetal genome and the development of tissues and organs via fetal programming. After parturition, maternal nutrition continues to regulate growth and development of piglets through maternal milk, which contains carbohydrates, lipids, proteins and oligosaccharides. Thus, deficiencies in maternal nutrition are detrimental to development of piglets, which can lead to inefficient growth and decreased carcass merit. Protein is an important nutritional component for sows, which not only functions in muscle development, but also plays a vital role in embryonic and neonatal development and lactation. Although effects of maternal undernutrition on neonatal development have been widely studied in sows, the function of different maternal dietary protein levels on fetal development, neonatal growth and lactation performance of sows is largely unknown. Determination of the effects and underlying mechanisms of maternal dietary protein levels on development of piglets is vital to the pork industry. Therefore, we summarized recent reports regarding mechanisms of effects of maternal protein levels on regulation of conceptus growth and early postnatal development though uterine fetal programming and lactation in swine.

Metabolomic Profiles Reveal Potential Factors that Correlate with Lactation Performance in Sow Milk

Sow milk contains necessary nutrients for piglets; however, the relationship between the levels of metabolites in sow milk and lactation performance has not been thoroughly elucidated to date. In this study, we analysed the metabolites in sow milk from Yorkshire sows with high lactation (HL) or low lactation (LL) performance; these categories were assigned based on the weight gain of piglets during the entire lactation period (D1 to D21). The concentration of milk fat in the colostrum tended to be higher in the HL group (P = 0.05), the level of mannitol was significantly lower in the HL group (P < 0.05) and the level of glucuronic acid lactone was significantly higher in the HL group (P < 0.05) compared to those in LL group. In mature milk, the levels of lactose, creatine, glutamine, glutamate, 4-hydroxyproline, alanine, asparagine, and glycine were significantly higher (P < 0.05) in the HL group than those in LL group. The level of fatty acids showed no significant difference between the two groups in both the colostrum and mature milk. This study suggested that lactation performance may be associated with the levels of lactose and several amino acids in sow milk, and these results can be used to develop new feed additives to improve lactation performance in sows.

348 The Effect of a Bacillus Subtilis-Based Direct-Fed Microbial Feed Additive on the Lactation Performance of Sows and Their Offspring.

348 The Effect of a Bacillus Subtilis-Based Direct-Fed Microbial Feed Additive on the Lactation Performance of Sows and Their Offspring.