Flavor supplementation during late gestation and lactation periods increases the reproductive performance and alters fecal microbiota of the sows

This study was conducted to evaluate the effect of flavor on reproductive performance and fecal microbiota of sows during late gestation and lactation. A total of 20 healthy Yorkshire sows were fed a corn-soybean basal diet unsupplemented or supplemented with 0.1% flavor compound from d 90 of gestation to 25 d post-farrowing, and then the piglets were weaned. The reproductive performance and the fecal microbiota of sows were analyzed. Compared with the controls, flavor supplementation in maternal diets increased (P < 0.05) weaning litter weight, litter weight gain, weaning body weight, and average daily gain of piglets. There was a trend of increase in the average daily feed intake of sows (P = 0.09) by maternal dietary flavor addition. The backfat thickness and litter size were not affected by flavor supplementation (P > 0.05). The 16S rRNA analysis showed that flavor supplementation significantly increased the abundance of Phascolarctobacterium (P < 0.05), but significantly decreased genera Terrisporobacter, Alloprevotella, Clostridium_sensu_stricto_1, and Escherichia-shigella (P < 0.05). Spearman correlation analysis showed that Phascolarctobacterum was positively correlated with the average daily feed intake of sows (P < 0.05), the litter weight gain and average daily gain of piglets (P < 0.05). In contrast, Clostridium_sensu_stricto_1 and unclassified_f__Lachnospiraceae were negatively correlated with the litter weight gain and average daily gain of piglets (P < 0.05). Taken together, dietary flavor supplementation improved the reproductive performance of the sows, which was associated with enhanced beneficial microbiota and decreased potentially pathogenic bacteria in the sows.     

Live yeast supplementation during late gestation and lactation affects reproductive performance,colostrum and milk composition,blood biochemical and immunological parameters of sows

This study was conducted to evaluate the effects of dietary live yeast (LY) supplementation during late gestation and lactation on reproductive performance, colostrum and milk composition, blood biochemical and immunological parameters of sows. A total of 40 multiparous sows were randomly fed either the control (CON) diet or the CON diet supplemented with LY at 1 g/kg from d 90 of gestation to weaning. Results showed that the number of stillborn piglets and low BW piglets were significantly decreased in the LY-supplemented sows compared with sows in the CON group (P < 0.05). Moreover, the concentrations of protein, lactose and solids-not-fat were increased in the colostrum of LY-supplemented sows (P < 0.05). Interestingly, the plasma activities of aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (γ-GGT) at d 1 of lactation and alanine aminotransferase (ALT) at weaning day were decreased by feeding LY diet (P < 0.05). Meanwhile, sows fed LY diet had higher plasma concentration of immunoglobulin G compared with sows fed CON diet at d 1 of lactation (P < 0.05). In conclusion, LY supplementation in maternal diets decreased the number of stillborn piglets and low BW piglets, improved colostrum quality and health status of sows.     

Maternal butyrate supplementation affects the lipid metabolism and fatty acid composition in the skeletal muscle of offspring piglets

Maternal sodium butyrate (SB) intake has important effects on offspring growth and development. This study aimed to investigate the impacts of maternal SB supplementation during gestation and lactation on fatty acid composition and lipid metabolism in the offspring skeletal muscle of pigs. Twenty sows (Yorkshire, parity 2 to 3) were assigned to the control group (diets without SB, n = 10) and SB group (diets with 0.1% SB, n = 10). The results showed maternal SB supplementation throughout gestation and lactation increased (P < 0.05) body weight of offspring piglets at weaning. The concentrations of triglyceride in plasma and milk were enhanced (P < 0.05). Maternal SB induced (P < 0.05) lipid accumulation with increased expression of peroxisome proliferator activated receptor γ (PPARγ) by enrichment of the acetylation of H3 acetylation K27 (H3K27) in offspring skeletal muscle. Meanwhile, the concentrations of C18:2n-6, C18:3n-3, total polyunsaturated fatty acid (PUFA), n-6 PUFA and n-3 PUFA decreased (P < 0.05) in skeletal muscle of weaning piglets derived from SB sows. Together, these results showed that maternal SB supplementation could influence offspring growth performance, lipid metabolism and fatty acid composition of the skeletal muscle.     

Supplementing daidzein in diets improves the reproductive performance,endocrine hormones and antioxidant capacity of multiparous sows

Certain hormones play important roles in modulating mammalian reproductive behaviour. Daidzein is a well-known isoflavonic phytoestrogen that possesses oestrogenic activity. This study was conducted to probe the effects of daidzein supplementation in gestation diets on the reproductive performance in sows. A total of 120 multiparous sows (Landrace × Yorkshire) were randomly assigned to 2 groups (n = 60) and fed either a base diet (control) or one containing 200 mg/kg daidzein during gestation. We discovered that daidzein supplementation significantly increased the total number of piglets born per litter and number of piglets born alive per litter (P < 0.05), decreased the farrowing time (P < 0.05) and increased the serum oestrogen and progesterone concentrations (P < 0.05) at 35 d of gestation. Moreover, serum immunoglobulin G (IgG) concentration and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were higher in the daidzein-treated group than in the control group at 35 d of gestation (P < 0.05). Daidzein increased the serum SOD activity and total anti-oxidative capacity (T-AOC) at 85 d of gestation (P < 0.05). Interestingly, daidzein elevated the expression levels of the sodium-coupled neutral amino acid transporter 1 (SLC38A1) and insulin-like growth factor 1 (IGF-1) genes in the placenta (P < 0.05). These results suggest that daidzein ingestion could improve sow reproductive performance by changing serum hormones, elevating anti-oxidative capacity and up-regulating critical functional genes in the placenta.     

Influence of dietary fat source on sow and litter performance,colostrum and milk fatty acid profile in late gestation and lactation

The objective of this study was to investigate the effects of dietary supplementation with various fat sources (3.8–3.9% of diet) during late pregnancy and lactation on the reproductive performance, fatty acids profile in colostrum, milk and serum of sow progeny. A total of 80 multiparous sows were randomly fed a control (adding no oil), palm oil (PO), fish oil (FO) or soybean oil (SO) supplemented diet from 90 days of pregnancy to weaning. Supplementation of FO increased litter size of weak piglets, compared with the control‐fed sows (P < 0.05). Dietary FO and SO supplementation, enhanced the weaning survival rate, litter weaning weight, litter weight gain and fat content in milk (P < 0.05). The highest immunoglobulin (Ig)G and IgM levels in colostrum and milk were observed in the FO group (P < 0.05). Meanwhile, the highest concentration of C22:5 (n‐3) and C22:6 (n‐3) in colostrum, milk and piglet serum was observed in the FO group (P < 0.05). Taken together, dietary inclusion of FO or SO improved growth performance of nursing piglets by increasing milk fat output, and FO consumption by sows might benefit the piglets via increasing n‐3 polyunsaturated fatty acid availability and immunoglobulins (IgG and IgM) secretion.     

Compensatory feeding during early gestation for sows with a high weight loss after a summer lactation increased piglet birth weight but reduced litter size

Sows mated in summer produce a greater proportion of born-light piglets (<1.1 kg) which contributes to increased carcass fatness in the progeny population. The reasons for the low birth weight of these piglets remain unclear, and there have been few successful mitigation strategies identified. We hypothesized that: 1) the low birth weight of progeny born to sows mated in summer may be associated with weight loss during the previous summer lactation; and 2) increasing early gestation feed allowance for the sows with high lactational weight loss in summer can help weight recovery and improve progeny birth weight. Sows were classified as having either low (av. 1%) or high (av. 7%) lactational weight loss in their summer lactation. All the sows with low lactational weight loss (LLStd) and half of the sows with high lactational weight loss received a standard gestation feeding regime (HLStd) (2.6 kg/d; day 0–30 gestation), whereas the rest of the sows with high lactational weight loss received a compensatory feed allowance (HLComp) (3.5 kg/d; day 0–30 gestation). A comparison of LLStd (n = 75) versus HLStd sows (n = 78) showed that this magnitude of weight loss over summer lactation did not affect the average piglet or litter birth weight, but such results may be influenced by the higher litter size (P = 0.030) observed in LLStd sows. A comparison of HLStd versus HLComp (n = 81) sows showed that the compensatory feeding increased (P = 0.021) weight gain of gestating sows by 6 kg, increased (P = 0.009) average piglet birth weight by 0.12 kg, tended to reduce (P = 0.054) the percentage of born-light piglets from 23.5% to 17.1% but reduced the litter size by 1.4 (P = 0.014). A subgroup of progeny stratified as born-light (0.8–1.1 kg) or -normal (1.3–1.7 kg) from each sow treatment were monitored for growth performance from weaning until 100 kg weight. The growth performance and carcass backfat of progeny were not affected by sow treatments. Born-light progeny had lower feed intake, lower growth rate, higher G:F, and higher carcass backfat than born-normal progeny (all P < 0.05). In summary, compensatory feeding from day 0 to 30 gestation in the sows with high weight loss during summer lactation reduced the percentage of born-light progeny at the cost of a lower litter size, which should improve growth rate and carcass leanness in the progeny population born to sows with high lactational weight loss.     

Effects of Dietary Supplementation of β‐hydroxy‐β‐methylbutyrate on Sow Performance and mRNA Expression of Myogenic Markers in Skeletal Muscle of Neonatal Piglets

The effects of dietary β‐hydroxy‐β‐methylbutyrate (HMB) supplementation during gestation on reproductive performance of sows and the mRNA expression of myogenic markers in skeletal muscle of neonatal pigs were determined. At day 35 of gestation, a total of 20 sows (Landrace × Yorkshire, at third parity) were randomly assigned to two groups, with each group receiving either a basal diet or the same diet supplemented with 4 g/day β‐hydroxy‐β‐methylbutyrate calcium (HMB‐Ca) until parturition. At parturition, the total and live litter size were not markedly different between treatments, however, the sows fed HMB diet had a decreased rate of stillborn piglets compared with the sows fed the control (CON) diets (p < 0.05). In addition, piglets from the sows fed HMB diet tended to have an increased birth weight (p = 0.08), and a reduced rate of low birth weight piglets (p = 0.05) compared with piglets from the CON sows. Nevertheless, lower feed intake during lactation was observed in the sows fed the HMB diet compared with those on the CON diet (p < 0.01). The relative weights of the longissimus dorsi (LD) and semitendinosus (ST) muscle were higher (p < 0.05) in neonatal pigs from the HMB than the CON sows. Furthermore, maternal HMB treatment increased the mRNA levels of the myogenic genes, including muscle regulatory factor‐4 (MRF4, p < 0.05), myogenic differentiation factor (MyoD) and insulin‐like growth factor‐1 (IGF‐1, p < 0.01). In conclusion, dietary HMB supplementation to sows at 4 g/day from day 35 of gestation to term significantly improves pregnancy outcomes and increases the expression of myogenic genes in skeletal muscle of neonatal piglets, but reduces feed intake of sows during lactation.     

Effects of dietary resveratrol supplementation during gestation and lactation of sows on milk composition of sows and fat metabolism of sucking piglets

The purpose of this article was to investigate the effects of dietary resveratrol supplementation during gestation and lactation of sows on the milk composition of sows and the fat metabolism of sucking piglets. Forty sows were allotted to two experimental treatment groups that included the following: (a) control sows (CON treatment, n = 20) fed with a corn–soybean meal control diet and (b) treatment sows (RES treatment, n = 20) fed with a control diet with addition of 300 mg/kg resveratrol. The results showed that the content of lactose in the colostrum was increased (p < 0.05) and the content of fat in 21‐day milk was increased (p < 0.05) by dietary resveratrol supplementation. In the RES treatment group, the concentrations of high‐density lipoprotein‐cholesterol (HDL‐C), low‐density lipoprotein‐cholesterol (LDL‐C), lipase activity and insulin (INS) in plasma of sucking piglets were increased (p < 0.05). In the adipose tissue, the enzyme activities of hormone‐sensitive lipase (HSL), acetyl‐CoA carboxylase (ACC) and lipoprotein lipase (LPL) increased significantly by RES treatment (p < 0.05), and the mRNA levels of acetyl coenzyme A‐alpha (ACCα), LPL, fatty acid transport protein (FATP1) and CCAAT–enhancer‐binding protein gene (C/EBPα) were higher in the RES treatment group (p < 0.05). In conclusion, resveratrol supplementation on gestational and lactating sows improved the content of lactose in the colostrum and the content of fat in milk at day 21 of lactation. In addition, resveratrol supplementation on sows increased HDL and LDL in the plasma of piglets. In piglet adipose tissue, the enzyme activity and mRNA level related to lipolysis, fatty acid uptake from circulating triacylglycerols and lipogenesis are partially improved by resveratrol supplementation on sows. These aspects affect fat metabolism in piglets.     

Effects of Inulin Supplementation in Low‐ or High‐Fat Diets on Reproductive Performance of Sows and Antioxidant Defence Capacity in Sows and Offspring

This experiment was conducted to investigate the effects of inulin supplementation in low‐ or high‐fat diets on both the reproductive performance of sow and the antioxidant defence capacity in sows and offspring. Sixty Landrace × Yorkshire sows were randomly allocated to four treatments with low‐fat diet (L), low‐fat diet containing 1.5% inulin (LI), high‐fat diet (H) and high‐fat diet containing 1.5% inulin (HI). Inulin‐rich diets lowered the within‐litter birth weight coefficient of variation (CV, p = 0.05) of piglets, increased the proportion of piglets weighing 1.0–1.5 kg at farrowing (p < 0.01), reduced the loss of body weight (BW) and backfat thickness (BF) during lactation (p < 0.05) and decreased the duration of farrowing as well as improved sow constipation (p < 0.05). Sows fed fat‐rich diets gained more BW during gestation (p < 0.01), farrowed a greater number of total (+1.65 pigs, p < 0.05) and alive (+1.52 pigs p < 0.05) piglets and had a heavier (+2.06 kg, p < 0.05) litter weight at birth as well as a decreased weaning‐to‐oestrous interval (WEI, p < 0.01) compared with sows fed low‐fat diets. However, it is worth noting that the H diet significantly decreased the serum activities of superoxide dismutase (T‐SOD) and glutathione peroxidase (GSH‐Px) and increased the serum malondialdehyde (MDA) levels in sows and piglets (p < 0.05). In contrast, HI diet enhanced the activities of T‐SOD and GSH‐Px and decreased the serum MDA concentrations (p < 0.05) in sows and piglets. In summary, the fat‐rich diets fed to sows during gestation had beneficial effects on reproductive performance, but aggravated the oxidative stress in sow and piglets. Inulin‐rich diets fed to sow during gestation had beneficial effects on within‐litter uniformity of piglet birthweight and enhanced the antioxidant defence capacity of sows and piglets.     

Effect of maternal organic selenium supplementation during pregnancy on sow reproductive performance and long-term effect on their progeny

Selenium (Se) is an essential trace element for animals and exists in nature in both inorganic and organic forms. Although organic Se is more bioavailable than inorganic Se, there are inconsistent reports on the effect of organic Se on the reproductive performance of sows. This study was conducted to investigate the effect of maternal organic Se (2-hydroxy-4-methylselenobutanoic [HMSeBA]) supplementation on reproductive performance and antioxidant capacity of sows, and the long-term effect on the growth performance and antioxidant capacity of their offspring with or without lipopolysaccharide (LPS) challenge. The experimental design used in this study was a completely randomized design; 45 Landrace × Yorkshire sows were randomly allocated to receive one of the following three diets during gestation: control diet (Control, basal diet, n = 15), sodium selenite (Na₂SeO₃)-supplemented diet (Na₂SeO₃, basal diet + 0.3 mg Se/kg Na₂SeO₃, n = 15), and HMSeBA-supplemented diet (HMSeBA, basal diet + 0.3 mg Se/kg HMSeBA, n = 15). On day 21 of age, male offspring from each group were injected with LPS or saline (n = 6). As compared with the control group, maternal HMSeBA supplementation increased the number of total born piglets, while decreased birth weight (P < 0.05). In the first week of lactation, maternal HMSeBA supplementation increased litter weight gain compared with the Na₂SeO₃ group (P < 0.05) and increased the average daily gain of piglets compared with the control group and Na₂SeO₃ group (P < 0.05). Meanwhile, maternal HMSeBA supplementation decreased piglet birth interval as compared with the control group and Na₂SeO₃ group (P < 0.05). Besides, plasma glutathione peroxidase (GSH-Px) activity was higher in the HMSeBA group on farrowing 0 min and 90 min, while malondialdehyde (MDA) concentration was lower on farrowing 0, 90, and 135 min than those in the control group (P < 0.05). In addition, maternal HMSeBA supplementation increased the concentration of selenoprotein P (SELENOP) in colostrum compared with the control group (P < 0.05). Further study revealed that the LPS-challenged HMSeBA group had higher GSH-Px and total antioxidant capacity and lower MDA in weaning piglets compared with the LPS-challenged control group (P < 0.05). Taken together, maternal HMSeBA supplementation increased the number of total born piglets, shortened the duration of farrowing, improved the antioxidant capacities of sows and their offspring, and improved the growth performance of suckling pigs at the first week of lactation. Thus, HMSeBA supplementation during gestation has the potentiality to produce more kilogram of meat.     

Fat and whey supplementation influence milk composition,backfat loss,and reproductive performance in lactating sows

This study investigates the effects of microencapsulated fat (FAT) and whey protein (WHEY) supplementation on the milk composition, backfat loss, and reproductive performance in lactating sows. A total of 144 sows were divided according to their backfat thickness at farrowing into three groups, i.e., low (12.0–16.5 mm, n?=?33), moderate (17.0–21.5 mm, n?=?78), and high (22.0–24.5 mm, n?=?33). The lactation diet was divided into three types, i.e., a control diet (CONTROL, n?=?50), a diet supplemented with FAT (n?=?48), and a diet supplemented with WHEY (n?=?50). Pooled milk samples were collected at the second and third week of lactation. On average, the sows lost backfat 23.5 % during lactation. The backfat loss during lactation was 24.5, 22.7, and 22.8 % in sows fed with CONTROL, FAT, and WHEY diets, respectively (P?>?0.05). Supplementation of FAT increased the percentage of fat in the sow’s milk compared to the CONTROL (9.1 and 8.4 %, P?=?0.022). For sows with low backfat, FAT and WHEY supplementation increased the average daily gain of piglets compared to the CONTROL (244, 236, and 205 g/days, respectively, P?<?0.05). For sows with high backfat, the sows receiving the CONTROL diet had a higher total piglet mortality than those that received FAT or WHEY (28.1, 14.1, and 13.0 %, respectively, P?<?0.05). It could be concluded that supplementation of FAT in the diet of sow during lactation significantly enhanced the fat content in the sow’s milk, improved the piglet’s daily weight gain, and reduced piglet mortality.     

Effect of ginseng polysaccharides on the immunity and growth of piglets by dietary supplementation during late pregnancy and lactating sows

There are many reports that dietary supplementation with plant polysaccharides in pigs might promote their growth, but little is known about the maternal effect of ginseng polysaccharides (GPS) on piglets’ growth by dietary supplementation to pregnant and lactating sows. In the current study, the effects of dietary supplementation with GPS on the immunity of sows and growth of their piglets were investigated. Results showed no significant difference among the four groups in the total number of piglets, live piglets, weak piglets and birth weight of piglets, indicating the GPS‐treatment has no adverse effect on reproduction. Furthermore, the weaning weight of the GPS‐treated groups was higher than that of control group (P < 0.05); among them, the addition of 200 mg/kg dose has the best effect. Interestingly, GPS increased the total immunoglobulin G concentration in milk and serum of sows (P < 0.05). The concentrations of interleukin (IL)‐2, IL‐6, tumor necrosis factor (TNF)‐α, and interferon‐γ in milk and serum of sows were also increased in the experimental groups relative to the control (P < 0.05). Meanwhile, maternal supplementation of GPS significantly increased IL‐2 and TNF‐α concentration in the piglets’ serum of the experimental groups relative to control (P < 0.05). GPS (200 mg/kg) significantly increased the glutathione peroxidase activity in milk and serum (P < 0.05), while the concentrations of malondialdehyde were significantly reduced (P < 0.05). The present results indicated that GPS supplementation during late pregnancy and lactation improved immunity‐related bio‐molecular levels in sow serum and milk, which may be further beneficial to piglet health and growth through biological transmission effects.     

Effects of different gestation housing types on reproductive performance of sows

This study evaluated the effects of different gestation housing types on reproductive performance of sows. A total of 60 sows (218 ± 24 kg body weight) with mixed parity were used. During gestation, 28 sows were housed in groups with electronic sow feeders (space allowance = 1.26 m²/sow) and 32 sows were housed in individual stalls (space allowance = 1.20 m²/sow). Sows from both housing types were moved to farrowing crates on day 109 of gestation and stayed until weaning (18 days post‐farrowing). Typical corn‐soybean meal diets were provided to sows during gestation and lactation. Measurements were reproductive performance of sows at farrowing as well as performance of sows and their litter during lactation. Similar total numbers of piglets born at farrowing were observed for sows gestated in both housing types. However, group‐housed gestation sows had more mummies (0.321 vs. 0.064; P < 0.05) and stillbirths (0.893 vs. 0.469; P = 0.073) at farrowing than individual‐housed gestation sows. Consequently, individual‐housing type had higher percentage of piglets born alive (95.5 vs. 90.4%; P < 0.05) than the group‐housing type. Therefore, improved reproductive performance of sows from individual gestating housing was confirmed in this study.     

Altrenogest Treatment Associated with a Farrowing Induction Protocol to Avoid Early Parturition in Sows

This study investigated the effect of altrenogest treatment on the farrowing development of sows, and birth weight (BW) and piglet survival until the third day of life. Three control groups were used: (i) sows that farrowed spontaneously before 114 day of gestation (CONT <114); (ii) sows that spontaneously farrowed at ≥114 day of gestation (CONT ≥114); (iii) sows that farrowed at ≥114 day with cloprostenol treatment (CONTCLOPR). Other sows were treated with altrenogest (Regumate^®) for 3 days (days 111, 112 and 113 of gestation): one group gave birth spontaneously (ALT) and the other group received altrenogest until day 113 and cloprostenol on day 114 (ALTCLOPR). There were no differences (p > 0.05) in farrowing duration, BW, coefficient of variation (CV) of BW, stillborn piglets, mummified foetuses, percentage of light piglets and survival until Day 3 between sows with and without cloprostenol treatment, in both control (CONT ≥114 vs CONTCLOPR) and altrenogest‐treated sows (ALT vs ALTCLOPR). Further comparisons were performed taking into account three groups: sows with early delivery (CONT <114 – farrowing before 114 days of gestation; n = 56), sows with longer gestation (CONT ≥114 – with and without cloprostenol treatment sows; n = 103) and ALT sows (with and without cloprostenol treatment; n = 105). Gestation length of CONT ≥114 and ALT sows was similar (p > 0.05), but higher than in CONT <114 sows. There were no differences (p > 0.05) between groups in farrowing duration, CV of BW, and percentages of stillborn piglets and mummified foetuses. Sows of CONT <114 group had a larger litter size and a lower BW than sows of the other two groups (p < 0.05). Sows of CONT <114 group had a higher percentage of lighter piglets and a lower piglet survival rate (p < 0.05) than ALT sows. In conclusion, altrenogest treatment proved to be an efficient method to avoid early parturition in 3–5 parity sows resulting in heavier piglets at birth.     

Starch supplementation improves the reproductive performance of sows in different glucose tolerance status

This study was to evaluate the effects of glucose tolerance status, maternal starch supplementation and soybean substitution in diets on the performance of dams and their offspring. Eighty-eight pregnant sows (Landrace × Large White) were selected from an initial total of 120 sows, based on blood glucose test values, and assigned to 4 experimental treatments in a 2 × 2 factorial design. The factors were glucose tolerance status (glucose intolerant [GIT] vs. normal glucose tolerant [NGT]) or dietary treatments (corn starch diet [CS] vs. soybean substitution diet [SS]). A higher area under the curve (AUC) for post-meal glucose was observed (P < 0.05) in the GIT group than in the NGT group on d 109 of gestation. The CS group had a lower value of homeostasis model assessment-insulin resistance than the SS group (P < 0.05) on d 109 of gestation. Corn starch supplementation for sows decreased the stillbirth rate (P < 0.05), regardless of the sows' glucose tolerance status. The villus height of the jejunum and the villus height to crypt depth ratio of the ileum were greater in normal birth weight piglets from the CS group than from the SS group (P < 0.01), and so was the activity of sucrase in the jejunum and ileum (P < 0.01). Compared with the SS group, the CS group showed a reduction in pre-weaning mortality rate, an increase in the number of high-birth-weight piglets, and a decrease in the number of low-birth-weight piglets (P < 0.05) under GIT status. In conclusion, sows fed CS decreased stillbirth rate and improved insulin resistance, as well as improving the intestinal morphology and digestive enzyme activities of their progeny, regardless of glucose tolerance status. Additionally, the CS group improved birth weight distribution and decreased pre-weaning mortality rate of piglets under GIT status.     

Variability of piglet birth weights: A systematic review and meta-analysis

The objective of the study was to evaluate the effects of litter size and supplementation of functional amino acids on the piglet birth weight variability through of a systematic review and meta-analysis. PubMed, ISI Web of Science, Science Direct, Scopus and SciELO are the main used databases and were searched in January 2019 by using the following keywords and their combinations: within-litter birth, weight variability, piglets, litter size, sow, amino acids, gestation, uniformity, CV and/or SD. Of the 64 pre-selected articles, only articles presenting the coefficients of variation and/or standard deviations according to the litter size and different levels of amino acid supplementation in the sow diets during gestation were selected. The average birth weights of total and live piglets were 43% lower in litters from sows with high prolificacy than those from sows with low prolificacy. The weight variability was affected by high prolificacy sows, with increases of 4.04% and 4.54% in the coefficients of variation of total and born alive piglets respectively (p = .074; p = .009). The standard deviation increased by 180 g in born alive piglets to high prolificacy sows. The coefficients of variation of total and live piglets born from high prolificacy sows showed an increase of 4.04% and 4.54% respectively (p = .07; p < .05). There was a tendency for reduced weight variability with amino acids supplementation when considering the standard deviation of total born (p = .072). However, reproductive performance was not significantly influenced (p > .05). In conclusion, the average litter weight and the number of piglets born influence weight variability. Amino acids supplementation may reduce the birth weight variability between piglets. However, this effect depends on the amino acid used, the levels of supplementation and on other factors not completely addressed in this study. Thus, more research is necessary to fully elucidate this topic.     

Combined yeast culture and organic selenium supplementation during late gestation and lactation improve preweaning piglet performance by enhancing the antioxidant capacity and milk content in nutrient-restricted sows

This study was conducted to investigate the effects of dietary supplementation with yeast culture (YC) and organic selenium (Se) during late gestation and lactation on reproductive performance, milk quality, piglet preweaning performance, antioxidant capacity, and secretion of immunoglobulin in multiparous sows. A total of 160 healthy cross-bred sows (Landrace × Yorkshire, mean parity 4.1 ± 0.3) were randomly assigned to 4 groups as follows: 1) high nutrient (HN), 3,420 kcal/kg digestible energy (DE) and 18.0% crude protein (CP); 2) low nutrient (LN), 3,240 kcal/kg DE and 16.0% CP; 3) LN + YC, LN diet + 10 g/kg YC; 4) LN + YC + Se, LN diet + 10 g/kg YC + organic Se (1 mg/kg Se). Feeding trials of sows started from d 85 of pregnancy to d 35 of lactation. Compared with sows in the LN group, sows fed the LN + YC + Se diet had greater litter weaning weight, average litter gain, and milk fat content (14-d and 25-d milk) (P < 0.05). The content of malonaldehyde (MDA) (colostrum and 14-d milk) was lesser, and the activity of glutathione peroxidase (GSH-Px) (colostrum and 25-d milk) was greater when sows were fed the LN + YC + Se diet, compared with sows fed the LN diet (P < 0.05). Supplementation of YC and organic Se in the nutrient-restricted diet improved sows’ reproductive performance and pig weaning body weight by enhancing the antioxidant capacity and fat content in milk.     

Maternal chitosan oligosaccharide intervention optimizes the production performance and health status of gilts and their offspring

Chitosan oligosaccharides (COS) are the hydrolyzed product of chitosan and have multifunctional health benefits. The objective of this study was to elucidate the effect of COS as a dietary supplement to gilts on their productivity and health and that of their litters. Gilts were randomly assigned to either a treatment (n = 30) or control group (n = 30). The treatment gilts were fed a standard dry sow ration supplemented with COS at 0.12 and 0.24 g/gilt per d during gestation and lactation, respectively, and the control group was fed the standard dry sow ration only. The body weight, reproductive performance, milk production and litter size for each gilt and body weight of corresponding litters were recorded. The serum immunoglobulins (IgA, IgG, IgM) and secretory immunoglobulin A (sIgA) concentrations of gilts and piglets and fecal sIgA concertation of gilts were measured by Enzyme-linked immunosorbent assay (ELISA). Our study showed that maternal COS supplementation 1) significantly increased gilt body weight in late pregnancy (P < 0.05), 2) significantly increased milk production of gilts at different stages (d 1, 3, 7 and 19) of lactation (P < 0.05), 3) significantly increased body weight gain of piglets at weaning (P < 0.05), 4) significantly increased the serum concentrations of IgM and sIgA in piglets, and sIgA in fecal sample of gilts (P < 0.05), and 5) tended to increase the pregnancy success rate (P > 0.05) in the treatment group compared to the control group. These results suggest that maternal COS intervention in gilts can improve gilt milk production, piglet pre-weaning growth and immunity parameters in both gilts and piglets.     

Effect of L-carnitine supplementation on performance parameters in gilts and sows

The effect of L-carnitine supplementation during pregnancy and lactation on performance parameters of sows was studied. The trial comprised a total of 127 sows (40 gilts, 87 mature sows) which were divided into a control and a treatment group. All animals were fed individually and received basic feed mixtures for pregnancy and lactation with low carnitine concentrations (gestation diet: 4.7 mg/kg feed, lactation diet: 12.5 mg/kg feed). The rations of the sows in the treated group were supplemented with 125 mg L -carnitine per head and day during pregnancy and 250 mg L -carnitine per head and day during lactation. The animals of the control group received identical feed mixtures in identical amounts, but without the L -carnitine supplement. L -carnitine supplementation resulted in higher sow liveweight gains between day 1 and day 85 of pregnancy. The number of piglets per litter and the number born alive did not differ between the control sows and those treated with L -carnitine. However, the L -carnitine-supplemented sows produced only half as many non-viable piglets as the control animals. Moreover, litter weight and mean birth weight of piglets from L -carnitine-treated sows were higher than in the control sows. This effect was more marked in gilts (+8% higher litter weight, +9% higher piglet weight) than in sows (+7% and +6%, respectively). Piglets from sows whose ration was supplemented with L -carnitine showed higher liveweight gains during the suckling period (+12% for gilts, +4% for sows), which is why litter weights post weaning were also higher among the sows treated with L -carnitine than in the control sows (+14% for gilts, +10% for sows). Overall, the study shows that dietary supplementation with L -carnitine during pregnancy and lactation improves the reproductive performance of sows.