Effects of magnesium on the performance of sows and their piglets

The objective of this study was to evaluate the effects of supplemental magnesium (Mg) on the performance of gilts and parity 3 sows and their piglets. Fifty-six gilts (Trial 1) and 56 sows (Trial 2) were assigned to one of 4 treatments according to their mating weight, respectively. The treatments comprised corn-soybean meal based gestation and lactation diets (0.21% magnesium) supplemented with 0, 0.015, 0.03, or 0.045% Mg from mating until weaning. The results showed that magnesium supplementation significantly (P < 0.05) reduced the weaning to estrus interval in both gilts and sows. There were significant effects (P < 0.05) of supplemental magnesium on the total number of piglets born, born alive and weaned in sows. In late gestation and lactation, the digestibility of crude fiber (quadratic effects, P < 0.05), and crude protein (P < 0.05), were significantly influenced by magnesium in gilts and sows, respectively. There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows (P < 0.05) during both early and late gestation. The apparent digestibility of gross energy was increased for sows in late gestation (P < 0.05), and lactation (quadratic effects, P < 0.05). At farrowing and weaning, serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased (P < 0.05). Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation (P < 0.05). The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium (P < 0.05). In addition, growth hormone levels were linearly elevated (P < 0.05) in the serum of piglets suckling sows. Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows, and the suitable supplemental dose ranged from 0.015% to 0.03%.     

Gut microbiota absence and transplantation affect growth and intestinal functions: An investigation in a germ-free pig model

This study was conducted to investigate host–microbiota interactions and explore the effects of maternal gut microbiota transplantation on the growth and intestinal functions of newborns in a germ-free (GF) pig model. Twelve hysterectomy-derived GF Bama piglets were reared in 6 sterile isolators. Among them, 6 were considered as the GF group, and the other 6 were orally inoculated with healthy sow fecal suspension as fecal microbiota transplanted (FMT) group. Another 6 piglets from natural birth were regarded as the conventional (CV) group. The GF and FMT groups were hand-fed with Co60-γ-irradiated sterile milk powder, while the CV group was reared by lactating Bama sows. All groups were fed for 21 days. Then, all piglets and then were switched to sterile feed for another 21 days. Results showed that the growth performance, nutrient digestibility, and concentrations of short-chain fatty acids in the GF group decreased (P < 0.05). Meanwhile, the serum urea nitrogen concentration and digesta pH values in the GF group increased compared with those in the FMT and CV groups (P < 0.05). Compared with the CV group, the GF group demonstrated upregulation in the mRNA expression levels of intestinal barrier function-related genes in the small intestine (P < 0.05). In addition, the mRNA abundances of intestinal development and absorption-related genes in the small intestine and colon were higher in the GF group than in the CV and FMT groups (P < 0.05). The FMT group exhibited greater growth performance, lipase activity, and nutrient digestibility (P < 0.05), higher mRNA expression levels of intestinal development and barrier-related genes in the small intestine (P < 0.05), and lower mRNA abundances of pro-inflammatory factor in the colon and jejunum (P < 0.05) than the CV group. In conclusion, the absence of gut microbes impaired the growth and nutrient digestibility, and healthy sow gut microbiota transplantation increased the growth and nutrient digestibility and improved the intestinal development and barrier function of newborn piglets, indicating the importance of intestinal microbes for intestinal development and functions.     

Yeast-based nucleotide supplementation in mother sows modifies the intestinal barrier function and immune response of neonatal pigs

In the present study, we aimed to evaluate the effects of maternal yeast-based nucleotide (YN) supplementation on the intestinal immune response and barrier function in neonatal pigs, as well as the diarrhoea rate and growth performance in suckling piglets. Sixty-four late-gestation sows were assigned to the following groups: the CON (fed a basal diet) and YN groups (fed a basal diet with 4 g YN/kg diet). The experiment started on d 85 of gestation and ended on d 20 of lactation. Diarrhoea rate and average daily gain of the piglets were recorded, and samples of blood and intestines from neonatal piglets were collected before they consumed colostrum during farrowing. Compared with the CON group, maternal YN supplementation increased the weaning weight of litter and decreased the diarrhoea rate (P < 0.01). In addition, maternal YN supplementation promoted the ileal villus development in the neonates compared with that in the CON group (P < 0.01). Maternal YN supplementation also increased the ileal secretory immunoglobulin A (sIgA) level compared with that in the CON group (P < 0.05). The real-time PCR results showed that maternal dietary YN supplementation increased the jejunal and ileal expression of interleukin (IL)-17, IL-8, IL-1β, IL-10 and tumor necrosis factor (TNF)- α in the neonates compared with that in the CON group (P < 0.05). Overall, maternal nucleotide supplementation improved the villus development and innate immunity of neonatal piglets during late pregnancy. This may be associated with the decrease in diarrhoea and the increase in weaning weight of the litter of suckling piglets.     

Effects of inorganic or organic selenium on immunoglobulins in swine

A study was conducted to determine if Se source fed during gestation and lactation affects passive transfer of immunoglobulins. Sixty days prior to breeding (d -60), gilts were randomly assigned to one of three treatments prior to breeding and throughout gestation: control (Control, no supplemental Se; n = 8), inorganic Se (Inorganic Se, 0.3 ppm; n = 4) and organic Se (Organic Se, 0.3 ppm; n = 4). Blood was collected on d -60, 57 and 113 of gestation and on d 21 of lactation and milk was collected at d 0, 1, 7, 14, and 21 of lactation. Blood was collected from piglets at d 0, 1, 7, 14, and 21 of age. Gilts fed organic Se had greater (P < 0.05) circulating concentrations of Se than Inorganic and Control gilts. Regardless of treatment, circulating concentrations of Se were greatest (P < 0.05) at d -60 compared to all other days. Serum concentrations of IgG were greatest (P < 0.05) in gilts at d 57 of gestation compared to d 113. Serum concentrations of IgA were greatest (P < 0.05) on d 113 of gestation and d 21 of lactation compared to d -60 and 57. Serum concentrations of IgM were greater (P < 0.05) at d 57 compared to d -60. Inorganic gilts had greater (P < 0.05) colostral and milk concentrations of IgG and IgM than Organic or Control gilts. Circulating concentrations of Se in piglets were greatest (P < 0.05) at d 14 and 21 of age compared to all other days. Piglets from gilts supplemented with organic Se had greater (P < 0.05) circulating concentrations of Se on d 1 versus piglets from gilts supplemented with no additional Se. The immunoglobulin concentrations of IgG, IgA, and IgM were lowest (P < 0.05) on d 0 and then increased when compared to d 1. The addition of different sources of Se did not affect the immunoglobulin concentrations in the gilt or piglet.     

Effects of dietary Forsythia suspensa extract supplementation to lactating sows and nursery pigs on post-weaning performance,antioxidant capacity,nutrient digestibility,immunoglobulins, and intestinal health

The aim of this study was to determine the effect of dietary Forsythia suspensa extract (FSE) supplementation to lactating sows and nursery pigs on post-weaning performance, antioxidant capacity, immunoglobulins, and intestinal health. Based on backfat, body weight (BW), and parity, 24 gestating sows (Landrace × Yorkshire) with average parity of 3.38 ± 0.61 and BW of 234 ± 6.81 kg were allotted into two dietary treatments (control vs. 100 mg/kg FSE) with 12 sows per treatment from day 107 of gestation to day 21 of lactation. After weaning, based on the initial BW and source litter, 192 nursery pigs (Duroc × [Landrace × Yorkshire], average BW of 6.98 ± 0.32 kg, weaned at day 21) were allotted into four dietary treatments with eight replicate pens per treatment, six pigs per pen for a 4-wk study. The treatments included the following: 1) CC (sows and their piglets both fed control diet); 2) CF (sows fed control diet and their piglets fed FSE diet [containing 100 mg/kg FSE]); 3) FC (sows fed FSE diet and their piglets fed control diet); and 4) FF (sows and their piglets both fed FSE diet). The MIXED procedures of SAS for a split-plot arrangement with sow diet as the whole plot and nursery diet as split plot were used to analyze the data. After weaning, piglets from FSE-fed sows had improved (P < 0.05) average daily gain and feed efficiency, and lower (P < 0.05) diarrhea rate in overall (day 1 to 28) compared with those from sows fed control diet. Piglets from FSE-fed sows also had higher (P < 0.05) contents of immunoglobulin G (IgG), growth hormone, superoxide dismutase (SOD), total antioxidant capacity in serum, villus height in ileum, and villus height to crypt depth ratio in jejunum, as well as lower (P < 0.05) content of malondialdehyde (MDA) in serum and crypt depth in ileum compared with those from sows fed control diet. Piglets fed FSE during nursery had increased (P < 0.05) concentrations of IgG, SOD, and catalase, and decreased (P < 0.05) MDA and tumor nuclear factor-α levels in serum compared with those fed control diet during nursery. Piglets from FC group had increased (P < 0.05) protein expression of occludin in jejunal mucosa and relative abundance of Lactobacillus on genus level in colon compared with those from CC group. In conclusion, for the performance and intestinal health, diets supplemented with FSE during lactation phase seemed more efficient to alleviate weaning stress than the nursery phase. In terms of the antioxidant status and immunoglobulins, FSE supplemented in both phases were efficient for nursery pigs.     

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.     

Effects of dietary soluble or insoluble fiber intake in late gestation on litter performance,milk composition,immune function,and redox status of sows around parturition

The objective of this study was to investigate the effects of dietary soluble fiber (SF) or insoluble fiber (ISF) intake in late gestation on litter performance, milk composition, immune function, and redox status of sows around parturition. A total of 60 Yorkshire sows were randomly assigned into three dietary treatments: normal level of dietary fiber (CON, 16.16% dietary fiber with 1.78% soluble fiber and 14.38% insoluble fiber), high insoluble fiber (ISF, 30.12% dietary fiber with 2.97% soluble fiber and 27.15% insoluble fiber), and high soluble fiber (SF, 30.15% dietary fiber with 4.57% soluble fiber and 25.58% insoluble fiber). Digestible energy and crude protein intake were comparable among treatments via adjusting feed intake from day 90 of gestation to parturition. After parturition, all sows were fed the same lactation diet. Results showed that litter performance of sows was not markedly affected by maternal fiber intake. However, sows fed ISF or SF diet had increased concentration of plasma mmunoglobulin G at day 107 (P < 0.05) and parturition (P < 0.01), and the SF diet had a tendency to increase fat content in both colostrum and milk relative to the CON diet. Furthermore, sows fed ISF diet had increased glutathione peroxidase activity (P < 0.05) at day 107, but decreased the plasma level of malondialdehyde at parturition (P < 0.05). High maternal SF intake tended to decrease the number of weaned piglets due to the increased preweaning mortality, as compared with sows fed the ISF diet. In conclusion, high fiber intake in late gestation may improve immune function and redox status, but differentially influenced the milk composition and preweaning mortality.     

Aggression and cortisol levels in three different group housing routines for lactating sows

Background

Lactating sows in Swedish organic piglet production are commonly group-housed with piglets in a multi-suckling pen within 14 days after farrowing. Nursing behaviour may be disturbed when lactating sows are moved to a new environment and mixed with other sows, as they spend more time fighting with other sows and exploring the new surroundings. This can disrupt the inhibitory effect of suckling on ovarian activity and increase the risk of lactational oestrus, making efficient reproductive management difficult. Therefore this study evaluated aggression and levels of the stress hormone cortisol in lactating sows group-housed together with their piglets at one (W1), two (W2) or three (W3) weeks post farrowing.

Results

There was no significant difference (P > 0.05) between the three management routines (W1, W2, W3) regarding number of attacks initiated or received in the mixed group. After mixing, W2 sows had a lower number of shoulder scratches (P < 0.05) than W3 sows. Among the W3 sows, there was a lower (P < 0.01) cortisol concentration in saliva when sows were group housed compared to when they were individually housed. The cortisol response, measured as variation in cortisol concentration in saliva, was also lower (P < 0.05) in group-housed W3 sows compared with W1 sows.For all management routines, sows already living in the new environment (resident sows) initiated more attacks (P < 0.001) and received fewer attacks (P < 0.01) than sows entering the new environment (intruder sows). Overall, multiparous sows initiated more attacks and received fewer attacks than primiparous sows (P <0.001).

Conclusions

Overall, the results suggest that mixing and group housing sows at three weeks post farrowing is less stressful than mixing and group housing sows at one week post farrowing. The results also indicate that parity and whether a sow is a resident or intruder in the group housing environment may have an effect on aggression levels when sows are group-housed.     

Effects of cooled floor pads combined with chilled drinking water on behavior and performance of lactating sows under heat stress

This study was conducted to evaluate whether cooled floor pads combined with chilled drinking water could alleviate negative impacts of heat stress on lactating sows. Thirty sows (Landrace × Yorkshire, Parity = 1 to 6) were housed in individual farrowing stalls in two rooms with temperatures being controlled at 29.4°C (0700–1900 hours) and 23.9°C (1900–0700 hours). Sows in one room (Cool), but not in the other room (Control) were provided cooled floor pads (21–22°C) and chilled drinking water (13–15°C). Behavior of sows (15 sows/treatment) was video recorded during farrowing, and days 1, 3, 7, 14, and 21 after farrowing. Videos were viewed continuously to register the birth time of each piglet, from which total farrowing duration and birth intervals were calculated. The number of drinking bouts and the duration of each drinking bout were registered for each sow through viewing videos continuously for 2 h (1530–1730 hours) each video-recording day. Postures (lying laterally, lying ventrally, sitting, and standing) were recorded by scanning video recordings at 5-min intervals for 24 h each video-recording day, and time budget for each posture was calculated. Rectal temperature and respiration rate were measured for all sows the day before and after farrowing, and then once weekly. Sow and litter performance was recorded. Data were analyzed using the Glimmix procedure of SAS. The cooling treatment did not affect sow behavior or litter performance. Sows in the Cool room had lower rectal temperature (P = 0.03) and lower respiration rate (P < 0.001), consumed more feed (P = 0.03), tended to have reduced weight loss (P = 0.07), and backfat loss (P = 0.07) during lactation than sows in the Control room. As lactation progressed, sows increased drinking frequency (P < 0.001) and time spent lying ventrally (P < 0.0001), standing (P < 0.001), and sitting (P < 0.0001), and decreased time spent lying laterally (P < 0.0001) in both Cool and Control rooms. While cooled floor pads combined with chilled drinking water did not affect sow behavior, they did alleviate heat stress partially, as indicated by decreased rectal temperature, respiration rate, weight, and backfat loss, and increased feed intake in lactating sows.     

Effects of dietary ratio of n-6 to n-3 polyunsaturated fatty acids on immunoglobulins,cytokines, fatty acid composition,and performance of lactating sows and suckling piglets

This experiment was conducted to investigate the effects of dietary ratios of n-6:n-3 polyunsaturated fatty acids (PUFA) on the performance of lactating sows and their piglets. Thirty pregnant Landrace sows were assigned to one of three treatments from d 108 of gestation until weaning (26–29 d) and were fed diets containing different ratios of n-6:n-3 PUFA including 3:1, 9:1 and 13:1. The effects on sow and litter production traits were examined together with an assessment of sow body condition. No differences were detected among the treatments for the daily feed intake of sows or changes in sow weight and back-fat levels during lactation (P > 0.05). Litter size at d 14 and d 21 were tended to increase in 3:1 treatment compared with 9:1 and 13:1 treatments (P < 0.10). Litter weight gain (1.77 kg/d) from d 0 to d 14 was tended to increase in 9:1 groups compared with the other two treatments (P < 0.10). A significant difference was observed for the content of α -linolenic acid, total n-3 PUFA, and the ratio of n-6:n-3 PUFA in the colostrum, milk, and piglets plasma (P < 0.01). The effects of different ratios of n-6:n-3 PUFA in sow diets on colostrum, milk, and piglet plasma immunoglobulin concentrations are studied. No difference was observed among treatments in the concentrations of IgM, and IgA in colostrum (P > 0.05). A great significant difference for IgG concentration was observed among 3 group in colostrum. A great significant difference for IgA, and IgM (P < 0.01) concentrations in piglet plasma at d14 and a significant difference for IgG(P < 0.05) was observed at d14. Furthermore, at d 21 of lactation, piglet plasma IgG and IgA concentration were greater in 3:1 compared with 13:1 group (P < 0.01).In summary, the current study demonstrated that altering the ratio of n-6:n-3 PUFA in lactating sow diet had an effect on the immune component including immunoglobulin and cytokines, and it tended to increase the litter average daily gain and improve the immune status of piglets when dietary ratio of n-6:n-3 PUFA was 9:1.     

Thermoregulatory and physiological responses of nonpregnant,mid-gestation,and late-gestation sows exposed to incrementally increasing dry bulb temperature

Gestating sows may be more susceptible to increasing dry bulb temperatures (T_DB) due to greater metabolic heat production and increased body mass, especially as gestation advances. However, there are few studies on the thermoregulatory and physiological responses of sows at differing gestation stages exposed to gradually increasing temperatures. The study objective was to determine the thermoregulatory and physiological responses of nonpregnant (n = 12; parity 3.27 ± 0.86), mid-gestation (59.7 ± 9.6 d pregnant, n = 12; parity 3.25 ± 0.83), and late-gestation (99.0 ± 4.8 d pregnant, n = 12; parity 3.33 ± 0.75) sows exposed to increasing T_DB. Prior to the experiment (5.0 ± 0.7 d), jugular catheters were placed in all sows. During the experiment, the T_DB was increased incrementally by 2.45 ± 0.43 °C every 60 min from 19.84 ± 2.15 to 35.54 ± 0.43 °C over 400 min, and relative humidity was recorded at 40.49 ± 18.57%. Respiration rate (RR), heart rate (HR), skin temperature, and vaginal temperature were measured, and blood samples were obtained via the jugular catheter every 20 min. Data were analyzed using PROC MIXED in SAS 9.4. RR increased at a lower T_DB (P < 0.01) in late-gestation sows compared with mid-gestation and nonpregnant sows, but no differences were detected between mid-gestation and nonpregnant sows. Overall, late-gestation sows had greater RR (P < 0.01; 23 ± 2 breaths per min [brpm]) compared with mid-gestation (16 ± 2 brpm) and nonpregnant (15 ± 2 brpm) sows. Late-gestation sows had an overall greater HR (P < 0.01; 84 ± 5 beats per min [bpm]) than mid-gestation (76 ± 5 bpm) and nonpregnant (69 ± 5 bpm) sows. Late-gestation sows had overall reduced bicarbonate and total carbon dioxide levels (P = 0.02; 23.89 ± 1.97 and 25.41 ± 2.07 mmol/L, respectively) compared with mid-gestation (27.03 ± 1.97 and 28.58 ± 2.07 mmol/L, respectively) and nonpregnant (26.08 ± 1.97 and 27.58 ± 2.07 mmol/L, respectively) sows. Moreover, late-gestation sows had overall greater nitric oxide levels (P < 0.01; 248.82 ± 34.54 µM) compared with mid-gestation (110.47 ± 34.54 µM) and nonpregnant (41.55 ± 34.54 µM) sows. In summary, late-gestation sows appear to be more sensitive to increasing T_DB as indicated by thermoregulatory and physiological responses when compared with mid-gestation or nonpregnant sows. The results from this study provide valuable information regarding thermoregulatory thresholds of sows at differing gestation stages.     

Program of vaccination and antibiotic treatment to control polyserositis caused by Haemophilus parasuis under field conditions

The present study investigated the effects of vaccinating sows and piglets or piglets alone against Haemophilus parasuis on the prevalence of H. parasuis in nasal swabs, on the humoral and cellular immune responses, and on the production parameters of piglets at 3 Korean farms with a clinical history of polyserositis caused by H. parasuis. Piglets born to vaccinated or non-vaccinated sows were subdivided into 3 groups: vaccinated sows and vaccinated pigs (VS-VP), non-vaccinated sows and vaccinated pigs (NVS-VP), and non-vaccinated sows and non-vaccinated pigs (NVS-NVP). The proportion of piglets with positive nasal swabs was significantly lower (P < 0.05) in the vaccinated animals (VS-VP and NVS-VP groups) than in the non-vaccinated animals (NVS-NVP group) at 35 and 60 d of age at the 3 farms. The overall growth performance (from 7 to 60 d of age) of the vaccinated piglets was significantly better (P < 0.05) than that of the non-vaccinated piglets at the 3 farms. Piglets in the VS-VP group had significantly higher levels (P < 0.05) of H. parasuis-specific IgG antibodies, lymphocyte proliferation, and interferon-γ-secreting cells than piglets in the NVS-VP and NVS-NVP groups on days 1, 7, 21, 35, and 60 after birth at the 3 farms.     

Dietary dihydroartemisinin supplementation alleviates intestinal inflammatory injury through TLR4/NOD/NF-κB signaling pathway in weaned piglets with intrauterine growth retardation

The aim of present study was to evaluate whether diets supplemented with dihydroartemisinin (DHA) could alleviate intestinal inflammatory injury in weaned piglets with intrauterine growth retardation (IUGR). Twelve normal birth weight (NBW) piglets and 12 piglets with IUGR were fed a basal diet (NBW-CON and IUCR-CON groups), and another 12 piglets with IUGR were fed the basal diet supplemented with DHA at 80 mg/kg (IUGR-DHA group) from 21 to 49 d of age. At 49 d of age, 8 piglets with similar body weight in each group were sacrificed. The jejunal and ileal samples were collected for further analysis. The results showed that IUGR impaired intestinal morphology, increased intestinal inflammatory response, raised enterocyte apoptosis and reduced enterocyte proliferation and activated transmembrane toll-like receptor 4 (TLR4)/nucleotide-binding and oligomerization domain (NOD)/nuclear factor-κB (NF-κB) signaling pathway. Dihydroartemisinin inclusion ameliorated intestinal morphology, indicated by increased villus height, villus height-to-crypt depth ratio, villus surface area and decreased villus width of piglets with IUGR (P < 0.05). Compared with NBW piglets, IUGR piglets supplemented with DHA exhibited higher apoptosis index and caspase-3 expression, and lower proliferation index and proliferating cell nuclear antigen expression in the intestine (P < 0.05). Dihydroartemisinin supplementation attenuated the intestinal inflammation of piglets with IUGR, indicated by increased concentrations of intestinal inflammatory cytokines and lipopolysaccharides (P < 0.05). In addition, DHA supplementation down-regulated the related mRNA expressions of TLR4/NOD/NF-κB signaling pathway and upregulated mRNA expressions of negative regulators of TLR4 and NOD signaling pathway in the intestine of piglets with IUGR (P < 0.05). Piglets in the IUGR-DHA group showed lower protein expressions of TLR4, phosphorylated NF-κB (pNF-κB) inhibitor α, nuclear pNF-κB, and higher protein expression of cytoplasmic pNF-κB in the intestine than those in the IUGR-CON group (P < 0.05). In conclusion, DHA supplementation could improve intestinal morphology, regulate enterocyte proliferation and apoptosis, and alleviate intestinal inflammation through TLR4/NOD/NF-κB signaling pathway in weaned piglets with IUGR.     

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.     

Inclusion of wheat aleurone in gestation diets improves postprandial satiety,stress status and stillbirth rate of sows

This study investigated the effects of different amounts of wheat aleurone (WA) (0, 15%, 30%) inclusion in gestation diets on the reproductive performance, postprandial satiety, stress status and stereotypic behaviors of sows. A total of 84 Landrace × Yorkshire sows (parity 4.87 ± 1.32) at breeding were randomly allotted to one of the three isoenergetic and isonitrogenous dietary treatments based on parity and body weight. The results showed that, compared with the control (0), sows fed the WA diet had a higher serum concentration of peptide YY (PYY) (P < 0.05) and glucagon like peptide-1 (GLP-1) (P < 0.05) and a lower concentration of saliva cortisol (P < 0.01). Importantly, compared with the control group, only the 15% WA group had a higher concentration of the total antioxidant capacity (T-AOC) (P < 0.05), lower proportions of sitting (P = 0.05) and stillbirth rates (P < 0.01). Accordingly, the production cost per piglet born alive ($ 6.9 vs. $ 7.6) or per piglet born healthy ($ 7.4 vs. $ 7.9) declined in the 15% WA group versus the control group. Overall, 15% WA inclusion in gestation diets contributed to enhancing postprandial satiety, alleviating stress status and decreasing stillbirth rate of sows. This study provides a reference for the application of WA as a partial substitute for conventional feed ingredients to improve sows’ reproductive performance.     

Shotgun proteomics of homogenate milk reveals dynamic changes in protein abundances between colostrum,transitional, and mature milk of swine

Milk is an easily digestible source of nutrients and bioactive factors, its composition reflects the neonate’s needs, and changes from colostrum to transitional and mature milk. Our objective was to measure milk fat, lactose, total carbohydrate, and protein content in parallel with global proteome of homogenate milk samples to characterize changes across the three phases of swine lactation. Milk samples were collected from multiparous sows (n = 9) on postnatal day 0 (D0; colostrum), 3 (D3; early transitional), 7 (D7; late transitional), and 14 (D14; mature). On D3, percent fat (16 ± 2.1) and lactose (3.8 ± 0.3) were higher (P < 0.05) than on D0 (10 ± 3.9 and 1.5 ± 0.3, respectively). Levels of fat and lactose were not different between D3 and D14. Percent total protein decreased (P < 0.05) between D0 (11 ± 2.1) and D3 (5 ± 0.7), but there was no significant change in percent protein between D3 and D14. Total carbohydrates increased (P < 0.05) between D3 (944 ± 353 µg/mL) and D14 (1,150 ± 462 µg/mL). Quantitative proteomic analysis using liquid chromatography tandem mass spectrometry (LC-MS/MS) of homogenate D0, D3, and D14 milk samples (n = 6) identified 772 protein groups which corresponded to 501 individual protein-coding genes. A total of 207 high confidence proteins were detected in n = 3 sows/day. Of the high confidence proteins, 81 proteins were common among all 3 days of lactation. Among the proteins that decreased between the days (false discovery rate; FDR < 0.05) were multiple apolipoproteins and XDH which decreased between D0 to D3. Proteins that increased across the days (FDR < 0.05) were complement factors and 14-3-3 proteins (YWHAQ, YWHAE). Our data provide a good characterization of milk proteome changes that likely reflect mammary function as well as the neonate’s phase-specific developmental needs. This data may be useful in developing approaches to enhance the health and welfare of swine.     

Dietary supplementation with N-carbamoylglutamate initiated from the prepartum stage improves lactation performance of postpartum dairy cows

The objective of this study was to investigate the effects of supplementing N-carbamoylglutamate (NCG), an Arg enhancer, on amino acid (AA) supply and utilization and productive performance of early-lactating dairy cows. Thirty multiparous Chinese Holstein dairy cows were randomly divided into control (CON, n = 15) and NCG (CON diet supplemented with NCG at 20 g/d per cow, n = 15) groups at 4 wk before calving. Diets were offered individually in tie-stalls, and NCG was supplemented by top-dress feeding onto total mixed ration for the NCG group. The experiment lasted until wk 10 after calving. Dry matter intake tended to be higher (P = 0.06), and yields of milk (P < 0.01), milk protein (P < 0.01), and milk fat (P < 0.01) were higher in the NCG-cows than in the CON-cows. Plasma activities of aspartate aminotransferase (P < 0.01), alanine aminotransferase (P = 0.03), and plasma level of β-hydroxybutyrate (P = 0.04) were lower in the NCG-cows than in the CON-cows, whereas plasma glucose (P = 0.05) and nitric oxide (NO, P < 0.01) concentrations were higher. Coccygeal vein concentrations of Cys (P < 0.01), Pro (P < 0.01), Tyr (P = 0.05), most essential AA except Thr and His (P < 0.01), total essential AA (P < 0.01), and total AA (P < 0.01) were higher in the NCG-cows than in the CON-cows. The arterial supply of all AA was greater in the NCG-cows than in the CON-cows. The NCG-cows had higher mammary plasma flow of AA (P = 0.04) and clearance rate of Cys (P < 0.01), Pro (P < 0.01) and Asp (P < 0.01), and higher ratios of uptake to output of Met (P = 0.05), Lys (P < 0.01), Cys (P = 0.01), Pro (P = 0.03), and Asp (P = 0.01). In summary, addition of NCG initiated from the prepartum period improved the lactation performance of postpartum dairy cows, which might attribute to greater Arg and NO concentrations, as well as improved AA supply and utilization, liver function, and feed intake in these cows.     

Impact of four fiber-rich supplements on nutrient digestibility,colostrum production,and farrowing performance in sows

This study aimed to investigate the impact of dietary fiber (DF) sources on sow and litter performance, and apparent total tract digestibility (ATTD) of gross energy (GE) and nutrients. A total of 48 sows were stratified for body weight at mating and randomly assigned to one of four DF sources (mixed fiber [MF], palm kernel expellers [PKE], sugar beet pulp [SBP], or soy hulls [SH]) and fed the diet from mating until farrowing. Within DF treatments, sows were supplemented with one of two extra energy sources (glycerol or sugar dissolved in water), whereas a third group (control) received water from day 108 of gestation until farrowing. The number of total born, live-born, and stillborn pigs; birth time and birth weight of the pigs; farrowing duration; and farrowing assistance (FA) were recorded. Live-born pigs were weighed again at 12 and 24 h after birth to record weight gain, which was used to estimate intake and yield of colostrum. Blood samples were collected once daily from day −3 relative to farrowing until day 1 after farrowing in sows and once from selected pigs right after birth. Fecal samples were collected on day 114 of gestation and colostrum at 0, 12, 24, and 36 h after onset of farrowing. Intake of soluble and insoluble nonstarch polysaccharides (NSP) was greater for SBP (P < 0.001) and PKE (P < 0.001) supplemented sows, respectively, when compared with other groups. Farrowing duration and stillbirth rate were not affected by DF sources, but PKE and SH supplemented sows had greater FA than SBP and MF supplemented sows (P < 0.001). Extra energy supplement did not improve the farrowing performance. Concentration (P = 0.02) and output (P = 0.04) of dry matter in colostrum, and ATTD of GE (P < 0.001) and crude protein (CP; P < 0.001) were lower for PKE supplemented sows than in sows from the remaining groups. Intake of insoluble NSP correlated negatively with ATTD of GE (P < 0.001) and CP (P < 0.001). Concentrations of glucose (P < 0.001), lactate (P < 0.001), CO₂ (P < 0.001), and HCO₃ (P < 0.001) in sows blood were increased with time progress relative to farrowing. Newborn pigs from PKE supplemented sows had greater concentration of lactate (P = 0.02) and lower blood pH (P = 0.02) than the remaining treatments. In conclusion, PKE supplement reduced ATTD of GE and CP, and concentration and output of dry matter in colostrum but increased FA. Results of this experiment indicated that the use of PKE as a fiber source for late gestating sows should be avoided.     

Regulatory role of l-proline in fetal pig growth and intestinal epithelial cell proliferation

l-proline (Pro) is a precursor of ornithine, which is converted into polyamines via ornithine decarboxylase (ODC). Polyamines plays a key role in the proliferation of intestinal epithelial cells. The study investigated the effect of Pro on polyamine metabolism and cell proliferation on porcine enterocytes in vivo and in vitro. Twenty-four Huanjiang mini-pigs were randomly assigned into 1 of 3 groups and fed a basal diet that contained 0.77% alanine (Ala, iso-nitrogenous control), 1% Pro or 1% Pro + 0.0167% α-difluoromethylornithine (DFMO) from d 15 to 70 of gestation. The fetal body weight and number of fetuses per litter were determined, and the small and large intestines were obtained on d 70 ± 1.78 of gestation. The in vitro study was performed in intestinal porcine epithelial (IPEC-J2) cells cultured in Dulbecco''s modified Eagle medium-high glucose (DMEM-H) containing 0 μmol/L Pro, 400 μmol/L Pro, or 400 μmol/L Pro + 10 mmol/L DFMO for 4 d. The results showed that maternal dietary supplementation with 1% Pro increased fetal weight; the protein and DNA concentrations of the fetal small intestine; and mRNA levels for potassium voltage-gated channel, shaker-related subfamily, member 1 (Kv1.1) in the fetal small and large intestines (P < 0.05). Supplementing Pro to either gilts or IPEC-J2 cells increased ODC protein abundances and polyamine concentrations in the fetal intestines and IPEC-J2 cells (P < 0.05). In comparison with the Pro group, the combined administration of Pro and DFMO reduced the expression of ODC protein and spermine concentration in the fetal intestine, as well as the concentrations of putrescine, spermidine and spermine in IPEC-J2 cells (P < 0.05). Meanwhile, the percentage of cells in the S-phase and the mRNA levels of proto-oncogenes c-fos and c-myc were increased in response to Pro supplementation, whereas depletion of cellular polyamines with DFMO increased tumor protein p53 (p53) mRNA levels (P < 0.05). Taken together, dietary supplementation with Pro improved fetal pig growth and intestinal epithelial cell proliferation via enhancing polyamine synthesis.