Performance Of Sows Research Articles

Use of a precision feeding program during gestation improves the performance of high-producing sows

Current gestating sow feeding strategies are based on using a single diet regardless of parity or gestation stage. Precision feeding (PF) of the individual sows allows dynamic changes in amino acid and energy requirements throughout gestation. The hypothesis of the study was that meeting the daily predicted amino acid and energy demands of gestating sows using a mathematical model and automatic precision feeder to establish the nutrition programs, would improve reproductive and productive performance compared to conventional feeding programs. Seventy-five mixed-parity sows were distributed among 3 treatments. A treatment managed as flat curve (FLAT: 2.1 kg/d, 1 – 110 d), a high-low-high curve (HLH: 2.2 kg/d, 1 – 49 d; 2.0 kg/d, 50 – 84 d; 2.6 kg/d, 85 – 110 d), where sows received the same diet with 3.2 Mcal/kg of metabolizable energy (ME) and 0.7 g/kg of standardized ileal digestible (SID) lysine. For the PF treatment, feeding level and blend of 2 basal diets (3.0 Mcal/kg of ME; 8.0 and 2.0 g/kg of SID lysine for high and low lysine, respectively) was adjusted daily for each sow to accurately meet estimated amino acid and energy requirements based on live weight, gestation stage and parity. Sows fed PF were heavier on d 110 of gestation (P = 0.011) and tended to increase total number of born (P = 0.092) and born alive (P = 0.077). Sows fed PF showed a higher litter weight (P = 0.003) at birth, lower lactation feed intake (P = 0.010), higher milk yield (P = 0.043) and a larger litter size (P = 0.050). Precision feeding sows also presented an improved maternal transformation index (P = 0.013) when compared to HLH and FLAT. In conclusion, our results demonstrate that the application of PF strategies based on daily nutrient adjustments is highly beneficial for high-producing sows to support the dynamic needs for nutrient availability for the sow´s body growth, mammary gland and fetal development.

Effects of a Phytogenic Feed Additive on Redox Status, Blood Haematology, and Piglet Mortality in Primiparous Sows

This study aimed to investigate the effects of a polyphenolic phytogenic feed additive (PFA) based on plant extracts, such as Embelia officinalis, Ocimum sanctum and nut fibre, on the redox status, haematological parameters, and piglet mortality in sows. A total of 64 primiparous sows were divided into two groups: T1-control group: regular gestation (GF) and lactation feed (LF), T2 group: regular GF and LF supplemented with a PFA (10 g daily) for 14 days before and 7 days after the farrowing. Blood samples were collected 0–3 h after farrowing. Haematological parameters (Packed Cell Volume/PCV, White Blood Cells/WBC, Platelets/PLTs) were counted in blood smears. Thiobarbituric acid reactive substances (TBARS) and protein carbonyls (CARBS) levels were determined in sow plasma. The performance and reproductive parameters of sows at farrowing and weaning days were recorded. The mean numbers of PCV and PLT counts in the T2 group were higher in comparison to the T1 group (p = 0.041, p = 0.033, respectively). In contrast, the mean numbers of WBC and neutrophils were almost significantly higher in the T2 group (p = 0.051). The mean number of stillborn piglets was significantly higher in the T1 group (2.12) compared to the T2 group (1.03). The mean number of alive piglets 24 h after farrowing and the mean number of the weaned piglets were significantly higher in group T2 (13.9 vs. 15.4 and 12.6 vs. 14.3). Sows in group T2 had significantly more backfat at weaning than the sows in group T1 (13.3 vs. 12.7). The mean levels of CARBS (nmol/mL) and TBARS (μmol/L) in group T1 (24.8 and 18.7) were significantly higher in comparison to group T2 (18.3 and 14.9). In conclusion, the use of a polyphenolic PFA in sows has beneficial effects on their welfare and performance due to its antioxidative effects. Furthermore, PFAs appear to exert antithrombotic, anti-inflammatory, and protective effects on PLTs, WBCs, and RBCs, respectively.

Effects of Growth Hormone-Releasing Hormone (GHRH) Plasmid Treatment on the Reproductive Productivity of Sows in Primiparous and Multiparous Sow Breeds.

The effect of growth hormone-releasing hormone (GHRH) plasmid treatment on sow reproductive performance was examined. Forty pregnant sows (three-way crossbreed: Landrace × Yorkshire × Duroc) at 85 days of gestation were included in the study and consisted of twenty primiparous and twenty multiparous sows (third parity). Sows were randomly assigned to the control and treatment groups. The treatment group received 5 mg dose of GHRH plasmid injection via electroporation, whereas the control group received a phosphate buffer solution. Reproductive indicators, including serum insulin-like growth factor-1 (IGF-1) concentration and weaned piglet data, were assessed. In the GHRH plasmid-treated group, serum IGF-1 concentration significantly increased compared with that in the control group, a trend observed in primiparous and multiparous sows. The key indicator of reproductive performance, litter size, showed that for control primiparous sows (C-PS), it was 10.90 ± 0.99 kg, while for control multiparous sows (C-MS), it was 14.00 ± 0.67 kg. Furthermore, for primiparous sows treated with GHRH plasmid (G-PS), the litter size was 11.60 ± 0.97 kg, and for multiparous sows treated with GHRH plasmid (G-MS), it was 14.00 ± 0.82 kg. The GHRH plasmid-treated group also exhibited a higher number of total births and surviving piglet numbers, along with a decrease in stillborn piglets; however, there was no significant difference in birth weight. The results suggest that GHRH plasmid treatment can enhance the reproductive performance of sows.

Corn straw-saccharification fiber improved the reproductive performance of sows in the late gestation and lactation via lipid metabolism.

With the development of animal husbandry, the shortage of animal feedstuffs has become serious. Dietary fiber plays a crucial role in regulating animal health and production performance. The aim of this study was to investigate the effects of three kinds of corn straw-saccharification fibers (CSSF) such as high-fiber and low-saccharification (HFLS), medium-fiber and medium-saccharification (MFMS), low-fiber and high-saccharification (LFHS) CSSF on the reproductive performance of sows. Thirty-two primiparous Yorkshire sows were randomly assigned to 4 groups, 8 sows for each group. Group A was the basal diet as the control group; groups B - D were added with 6% HFLSCSSF, 6% MFMSCSSF and 6% LFHSCSSF to replace some parts of corn meal and wheat bran in the basal diet, respectively. The experimental period was from day 85 of gestation to the end of lactation (day 25 post-farrowing). The results showed that 6% LFHSCSSF addition significantly increased number of total born (alive) piglets, litter weight at birth (p < 0.05), whereas three kinds of CSSF significantly decreased backfat thickness of sows during gestation (p < 0.001), compared with the control group. Furthermore, CSSF improved the digestibility of crude protein, ether extract and fiber for sows. In addition, the levels of total cholesterol, total triglycerides, and high-density lipoprotein cholesterol in serum of sows were decreased by different kinds of CSSF. Further analysis revealed that CSSF regulated lipid metabolism through adjusting the serum metabolites such as 4-pyridoxic acid, phosphatidyl cholines and L-tyrosine. In summary, CSSF addition to the diets of sows during late gestation and lactation regulated lipid metabolism and improved reproductive performance of sows. This study provided a theoretical basis for the application of corn straw in sow diets.

Performance of sows of different genotypes

Performance of sows of different genotypes

Effect of phytosterols on the performance, lipid metabolism, and antioxidation capacity of Sows

Effect of phytosterols on the performance, lipid metabolism, and antioxidation capacity of Sows

Investigation of supplementation with a combination of fermented bean dregs and wheat bran for improving the growth performance of the sow.

To investigate the effect of dietary supplementation with a fermented mixture of bean dregs and wheat bran (FBW) on sow performance. FBW was given to sows during late gestation and lactation; in total, 24 sows were randomly assigned to 4 groups (control diet; 3% FBW diet; 6% FBW diet; 9% FBW diet, n = 6). The weight ratio of bean dregs (wet) to wheat bran was 4:6. Sows were fed different diets from 85 d of gestation until weaning. The results showed that supplementation with FBW increased average daily feed intake (ADFI) during lactation (p < 0.05). FBW supplementation also increased litter weight and milk yield (p < 0.05). The contents of Escherichia coli in the feces of the treatment groups were significantly reduced by FBW supplementation (p < 0.01). FBW supplementation significantly improved the fecal morphology (p < 0.05), alleviating sows' constipation. In conclusion, FBW could increase the ADFI, improve lactation and piglet litter weight in sows and reduce the pathogenic bacterial content in sow feces and constipation.

Effects of extra-feed intake during late gestation on reproductive performance of sow and piglet performance during weaning stage

Effects of extra-feed intake during late gestation on reproductive performance of sow and piglet performance during weaning stage

Saccharomyces yeast postbiotics supplemented in feeds for sows and growing pigs for its impact on growth performance of offspring and growing pigs in commercial farm environments.

Three experiments were conducted to evaluate the effects of Saccharomyces yeast postbiotics (SYP) in feeds for sows on the growth of offspring (Exp. 1), for nursery pigs on their growth (Exp. 2), and for nursery and finishing pigs on their growth (Exp. 3). Exp. 1 had 80 sows at breeding assigned to 4 groups with SYP at 0, 0.050, 0.175, and 0.500 g/kg. Offspring were fed a common diet for 126 d. Exp. 2 had 144 barrows at 8 kg body weight (BW) allotted to CON (no SYP); YPC (SYP at 0.175 g/kg; d 0 to 42); and YPD (SYP at 1.25, 0.75, and 0 g/kg; d 0 to 7, d 8 to 21, and d 22 to 42, respectively) with 8 pens/treatment (6 pigs/pen). Exp. 3 had 96 barrows at 8 kg BW allotted to CON (no SYP); YPN (SYP at 0.175 g/kg; d 0 to 42); YPF (SYP at 0.100 g/kg; d 43 to 119); and YPA (SYP at 0.175 and 0.100 g/kg; d 0 to 42 and d 43 to 119, respectively) with 8 pens/ treatment (3 pigs/pen). In Exp. 1, increasing SYP increased (p<0.05, quadratic) the sow body score (maximum at 0.30% SYP), reduced (p<0.05, quadratic) the days-wean-to-estrus (minimum at 0.27% SYP), and increased (p<0.05) offspring BW at weaning and their average daily gain (ADG) and feed efficiency (G:F) at d 126. In Exp. 2, ADG, average daily feed intake (ADFI), and G:F of YPC were the greatest (p<0.05). The ADG and ADFI of YPD were greater (p<0.05) than CON. Fecal score of YPC and YPD was smaller (p<0.05) than CON. In Exp. 3, YPA had the greatest (p<0.05) ADG and YPN and YPF had greater (p<0.05) ADG than CON. SYP enhanced sow performance, offspring growth, growth of nursery and growing pigs with the greater efficacy at 0.27 to 0.32 g/kg feed.

Large litters have a detrimental impact on litter performance and postpartum maternal behaviour in primiparous sows

BackgroundOur previous study confirmed that large litter size adversely affects prepartum maternal hormones and behaviour, concurrently with heightened oxidative stress in primiparous sows. The purpose of this study was to examine the effect of large litter size on litter performance, postpartum maternal behaviour, salivary cortisol levels, and colostral immunoglobulin levels in sows, as well as investigate their correlations with the levels of oxidative stress parameters.ResultsA total of 24 primiparous sows (Landrace\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \ imes $$\\end{document}Large white) and their offspring were categorised into two groups based on litter size: NORMAL (n = 8) with litter size ranging from 7 to 14 (mean 11.5\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\pm $$\\end{document}2.7), and LARGE (n=16) with litter size ranging from 15 to 20 (mean 15.9\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\pm $$\\end{document}1.4). All sows were housed in a group housing system during gestation and transitioned to an adaptable loose housing system (2.4\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \ imes $$\\end{document}2.3 m) during the farrowing and lactation periods. The nursing and carefulness behaviour of the sows was monitored over a 24-h period between 72 and 96 h after parturition. Saliva samples were collected for cortisol assay on 35, 21, and 7 days before parturition (D-35, D-21, and D-7, respectively), as well as on days 1, 7, and 28 after parturition (D1, D7, and D28, respectively). On D1, higher piglet mortality rates were observed among the LARGE group compared to the NORMAL group (p<0.01). The total and successful nursing behaviours of the sows were less frequent in the LARGE group than in the NORMAL group (p<0.05, for both), and the carefulness score of the LARGE group was also lower than that of the NORMAL group (p< 0.01). On D1, cortisol levels in LARGE sows were higher than those in NORMAL sows (p< 0.05), and for other time points (D-21, D-7, D7, and D28), cortisol levels in LARGE sows tended to be higher than those in NORMAL sows (p < 0.10, for all). Successful nursing behaviour displayed negative correlations with levels of salivary cortisol and certain oxidative stress parameters measured on D1.ConclusionsThese findings suggest that the strategy for alleviating physiological and oxidative stress during the peripartum periods could benefit potential postpartum maternal behaviour and litter performance in the sows with large litters.

Effect of heat stress on the reproductive performance of sows: comparison of different thermal-comfort indices in a temperate climate

Context Heat stress is a major environmental factor negatively affecting animal health and production efficiency of the sow, and causes significant economic losses to the global pig industry. Researchers have developed various thermal indices with different characteristics for assessing the level of heat stress in pigs, including the temperature–humidity index (THI), black globe–humidity index (BGHI), effective temperature (ET), equivalent temperature index of sows (ETIS), and enthalpy (H), among others. Aims The aim of this study was to evaluate the effect of heat stress on reproductive performance by using different thermal indices based on environmental variables in a temperate climate and to compare the goodness-of-fit among them. Methods In total, 2951 sow reproductive records were analysed for a Puebla farm in the northern hemisphere. Key results The overall means for pregnancy, farrowing, and abortion rates over the period from January to December 2020 were 83.1%, 80.67%, and 5.2%, whereas temperature, relative humidity, and air velocity were 24.3°C, 63.0%, and 3.7 m/s respectively. The highest rates of pregnancy and farrowing over the study period were observed in March, while the abortion rate was highest in December. However, the mean daily temperatures exceeded 25°C between March and June, being higher the upper limit of the thermoneutral zone for sows. Many thermal indices have been used to estimate the level of heat stress in pigs, such as the THI, BGHI, ET, and ETIS. We used 11 thermal indices to measure the degree of heat stress affecting fertility traits of animals. Pregnancy and farrowing rates were highest for THI2 and THI6 values, reflecting moderate stress at pregnancy and farrowing periods. Statistically significant differences were found between the THI2, THI4, THI6, and ET values and the pregnancy, farrowing, and abortion rates (P &lt; 0.05). Conclusions Our results showed that the THI2 performs better for evaluating the level of heat stress in sows than do other thermal-comfort indices such as the THI4, THI6, and ET. Implications These results may be useful for accurate assessment of heat stress to mitigate its effects and avoid significant economic losses in sows in temperate climates.

Cloprostenol sodium improves reproductive performance of multiparous sows during lactation.

This study aimed to determine the effect of prostaglandin F2α (PGF2α) analog (D-cloprostenol sodium and DL-cloprostenol sodium) administration on the milk yield of multiparous sows (MS) and piglet growth performance. In total, 320 Landrace×Yorkshire parturient MS were randomly divided into three groups on day 115 of pregnancy: without treatment (N = 50), with 75 μg D-cloprostenol sodium (N = 137), and with 200 μg DL-cloprostenol sodium (N = 133). After delivery, the sows treated with D-cloprostenol sodium and DL-cloprostenol sodium were randomly allocated into three subgroups, respectively: (i) no additional treatment after farrowing; (ii) administration of cloprostenol sodium at 3 h and 5 days after farrowing; and (iii) administration of cloprostenol sodium at 3 h, 5 days, and 10 days after farrowing. Cloprostenol sodium effectively induced sows to synchronize parturition approximately 23 h after administration and increased the daytime delivery rates (p < 0.05). Compared with DL-cloprostenol sodium, D-cloprostenol sodium shortened the farrowing duration and birth interval of sows for inducing farrowing (p < 0.05). Moreover, we observed that a single administration of both D-cloprostenol sodium and DL-cloprostenol sodium a day before delivery significantly reduced the rates of stillborn piglets type II in MS (p < 0.05). Compared to no treatment and single treatment with cloprostenol sodium, quartic treatments with cloprostenol sodium significantly increased the daily feed intake of MS, litter weight after weaning, and average daily gain of piglets (p < 0.05). Cloprostenol sodium improved the 21-day milk yield, with D-cloprostenol sodium showing the best effect, which increased lactation ability by 30.30% (176.72 kg vs. 135.63 kg) (p < 0.05). DL-cloprostenol sodium followed closely, increasing lactation ability by approximately 25.00% (169.71 kg vs. 135.63 kg) (p < 0.05). During lactation, sows administered with D-cloprostenol sodium observed increased serum prolactin levels. Compared to untreated sows, the sows administered with D-cloprostenol sodium and multiple DL-cloprostenol sodium visibly shortened the weaning-to-estrus interval (WEI) and weaning-to-service interval (WSI) (p < 0.05). Furthermore, quartic injections of D-cloprostenol sodium resulted in an 18 percentage point increase in the pregnancy rate of breeding sows compared to controls (82.61% vs. 64.58%) (p > 0.05). In summary, cloprostenol sodium could enhance the reproductive performance of MS, particularly in terms of lactation performance. Additionally, the effect of quartic injections of D-cloprostenol sodium was the most pronounced.

Dietary 25 Hydroxyvitamin D3 Improved Serum Concentration Level and Alkaline Phosphatase Activity during Lactation but Had Meager Impact on Post-Farrowing Reproductive Performance in Sows

Dietary 25 hydroxyvitamin D3 (25(OH)D3) promotes serum 25(OH)D3 concentration and alkaline phosphatase activity (ALP); however, post-farrowing reproductive performance of lactating sows fed with 14-epimer of 25(OH)D3 is uncertain. This study investigated post-farrowing reproductive performance, serum ALP activity, and serum 25(OH)D3 concentration in sows fed VD3, 25(OH)D3, or 14-epi 25(OH)D3. Weaned sows (n = 203) in parities 2 and 3 were blocked weekly and treated with 2000 IU/kg VD3 (T1), 25 μg/kg 25(OH)D3:14-epi 25(OH)D3 (T2), or 50 μg/kg 25(OH)D3 (T3) diets, all equilibrated to 2000 IU/kg as fed. Sow performance, treatment, and sampling period effects were analyzed. Environmental conditions were analyzed as covariates. The number of piglets weaned (p = 0.029), pre-weaning mortality (p = 0.029), sampling period (p &lt; 0.001), and treatment and period interaction (p = 0.028) differed significantly. There was an increase in 25(OH)D3 during lactation due to physiological demands for milk calcium and milk production. Supplementing twice the concentration of 25(OH)D3 compared to its epimer, 25(OH)D3:14-epi 25(OH)D3, had no significant effect on the post-farrowing reproductive performance of lactating sows. The effect of 25(OH)D3 on post-farrowing reproductive performance and ALP activity in sows was influenced by metabolic demand for calcium due to physiological changes during lactation as well as epimer conformation.

Rye Bran as a Component in the Diets of Lactating Sows—Effects on Sow and Piglet Performance

From a cost and sustainability perspective, the use of by-products such as rye bran in sow diets is of particular interest. Rye bran has valuable ingredients that have potential benefits for the gut health of sows. The aim of this study was to investigate the effects of including 15% rye bran in the sows’ feed on the performance of sows and piglets. The feeding started one week before the farrowing date and ended at weaning. Performance was evaluated by measuring sow (n = 175) and piglet body weight (n = 1372) and sows’ backfat thickness (n = 80). These data were additionally used to calculate the colostrum intake of the suckling piglets and the sows’ milk production. It was found that there were no differences in the performance parameters between the experimental and control groups. However, this study showed that the piglets with light birth weight (LBW (&lt;1000 g)) and medium birth weight (MBW (1000–1500 g) consumed more colostrum when the sows were fed rye bran (LBW: C/R 203.0 ± 39.2 g/214.3 ± 35.9 g; MBW: 291.3 ± 39.0 g/298.5 ± 36.4 g). It can be concluded that including 15% rye bran in the feed of lactating sows has no obvious negative effects on the performance of sows and piglets. Further studies are needed to evaluate the possible positive effects of rye bran.

Microbial Mechanistic Insight into the Role of Yeast-Derived Postbiotics in Improving Sow Reproductive Performance in Late Gestation and Lactation Sows.

The purpose of this study is to investigate the effects of supplementing Yeast-derived postbiotics (Y-dP) to the diet of sows during late pregnancy and lactation on fecal microbiota and short-chain fatty acids (SCFA) in sows and their offspring weaned piglets, as well as the relationship between gut microbiota and SCFA, serum cytokines, and sow reproductive performance. A total of 150 sows were divided into three groups: control diet (CON), CON + Y-dP 1.25 g/kg, and CON + Y-dP 2 g/kg. The results showed that supplementing 0.125% Y-dP to the diet of sows can increase the content of isobutyric acid (IBA) in the feces of pregnant sows and reduce the content of butyric acid (BA) in the feces of weaned piglets (p < 0.05). The fecal microbiota of pregnant sows β diversity reduced and piglet fecal microbiota β diversity increased (p < 0.05). Y-dP significantly increased the abundance of Actinobacteria and Limosilactobacilli in the feces of pregnant sows (p < 0.05), as well as the abundance of Verrucomicrobiota, Bacteroidota, and Fusobacteriota in the feces of piglets (p < 0.05). The abundance of Bacteroidota in the feces of pregnant sows is positively correlated with propionic acid (PA) (r > 0.5, p < 0.05). The abundance of Prevotellaceae_NK3B31_group was positively correlated with Acetic acid (AA), PA, Valerate acid (VA), and total volatile fatty acid (TVFA) in the feces of pregnant sows (r > 0.5, p < 0.05), and Bacteroidota and Prevotellaceae_NK3B31_group were negatively correlated with the number of stillbirths (r < -0.5, p < 0.05). The abundance of Lactobacillus and Holdemanella in piglet feces was positively correlated with TVFA in feces and negatively correlated with IgA in serum (r > 0.5, p < 0.05). In conclusion, supplementing Y-dP to the diet of sows from late gestation to lactation can increase the chao1 index and α diversity of fecal microorganisms in sows during lactation, increase the abundance of Actinobacteria and Limosilactobacilli in the feces of sows during pregnancy, and increase the abundance of beneficial bacteria such as Bacteroidetes in piglet feces, thereby improving intestinal health. These findings provide a reference for the application of Y-dP in sow production and a theoretical basis for Y-dP to improve sow production performance.

Effects of dietary iron supplementation on reproductive performance of sows and growth performance of piglets.

This experiment aimed to investigate the effects of dietary iron supplementation from different sources on the reproductive performance of sows and the growth performance of piglets. A total of 87 sows with similar farrowing time were blocked by body weight at day 85 of gestation, and assigned to one of three dietary treatments (n = 29 per treatment): basal diet, basal diet supplemented with 0.2% ferrous sulfate (FeSO4), and basal diet supplemented with 0.2% iron sucrose, respectively, with 30% iron in both FeSO4 and iron sucrose. Compared with the control (CON) group, iron sucrose supplementation reduced the rate of stillbirth and invalid of neonatal piglets (P < 0.05), and the number of mummified fetuses was 0. Moreover, it also improved the coat color of newborn piglets (P < 0.05). At the same time, the iron sucrose could also achieve 100% estrus rate of sows. Compared with the CON group, FeSO4 and iron sucrose supplementation increased the serum iron content of weaned piglets (P < 0.05). In addition, iron sucrose increased serum transferrin level of weaned piglets (P < 0.05) and the survival rate of piglets (P < 0.05). In general, both iron sucrose and FeSO4 could affect the blood iron status of weaned piglets, while iron sucrose also had a positive effect on the healthy development of newborn and weaned piglets, and was more effective than FeSO4 in improving the performance of sows and piglets.

Estimation of genotype by environmental interaction for litter traits by reaction norm model in Taiwan Landrace sows.

The negative effects of heat stress on swine reproduction have been well documented and the recent global warming trend caused by climate change is leading to more days with high temperatures every year. This has caused a reduction in litter trait performance of Landrace sows in Taiwan, a country extending across tropical and subtropical oceanic zones. Therefore, this study developed a modified model to determine which stages of pregnancy, before, early, middle, and late, had the largest impacts of heat stress on litter traits. A reaction norm model (RNM) was used to identify sows with high resilience to heat stress for litter traits followed by analysis of the modified model. Data from Landrace sows were collected from 2 farms in Taiwan between 2008 and 2021. A total of 11,059 records were collected for total number born (TNB), number born alive (NBA), and stillborn rate (STBR). The results showed that the heritabilities of TNB, NBA, and STBR were 0.170, 0.115, and 0.077, respectively. These results were similar between the conventional model and the modified model. In the modified model, the before and early stages of sow pregnancy were the significant periods for TNB and NBA (P < 0.05), while the early and middle stages were significant for STBR (P < 0.05). According to the RNM results, the heritability estimates for TNB, NBA, and STBR were 0.23 to 0.11, 0.18 to 0.08, and 0.10 to 0.04, respectively, showing a decrease from low temperature-humidity index (THI) to high THI. The minimum genetic correlations between the highest and the lowest THI for TNB, NBA, and STBR were 0.85, 0.64, and 0.80, respectively. The results of the RNM for breeding value showed re-ranking across THI values. In conclusion, similar results were obtained for heritability when the model was modified for heat stress estimation. Yet re-ranking of breeding values across THI could help farmers to select not only for improved litter trait performance but also for heat stress resilience of Landrace sows in Taiwan.

Optimal protein concentration in diets for sows during the transition period.

The aim of the present study was to determine the optimal concentration of dietary protein required in transition diets for multiparous sows that enhance the farrowing process, colostrum production, and subsequent lactation performance. Forty-eight multiparous sows were allotted to one of six dietary treatments according to body weight (290 ± 3kg) and parity (3.8 ± 0.2) from day 108 of gestation until 24hafter the onset of farrowing. The diets were isoenergetic and contained increasing concentrations of dietary protein (expressed as standardized ileal digestible [SID] Lys) and were supplied at a daily feed supply of 3.8kg. On day 108 of gestation and days 2, 7, 14, 21, and 28 of lactation, body weight, and back fat thickness were recorded, and blood was sampled on day 108 of gestation, at the onset of farrowing, and days 3, 10, 17, and 24 of lactation from the sows for analysis of plasma metabolites. On day 115 of gestation, urine, and feces were collected for nitrogen (N) balance. The number of liveborn and stillborn piglets and time of birth were recorded and blood from every fourth piglet was sampled at birth for blood gas analysis. Piglets were weighed individually from birth until weaning, to estimate the colostrum and milk yield of the sows. Colostrum and milk samples were collected, and their compositions were determined. On days 3 and 28 of lactation, sows were injected with deuterium oxide to estimate body composition. The N utilization was maximized when the concentration of SID Lys in the transition diet was 6.06g/kg (P < 0.01). When urinary concentrations of urea were expressed relative to creatinine, the relative concentration of urea remained low until a dietary concentration of 6.08g SID Lys/kg, above which the relative concentration of urea increased (P < 0.01). Stillbirth rate increased linearly with increasing SID Lys concentration in the transition diet (P < 0.001), thus the concentration of SID Lys should be kept as low as possible without impairing sow performance excessively. A carry-over effect on milk yield was observed, showing that a dietary SID Lys concentration of 5.79g/kg during transition optimized milk production at an average yield of 13.5kg/d (P = 0.04). Increasing loss of body fat in lactation was observed with increasing SID Lys concentration in the transition diet (P = 0.03). In conclusion, the transition diet of multiparous sows should contain 5.79g SID Lys/kg when fed 3.8kg/d (13.0 MJ ME/kg), for a total SID Lys intake of 22g/d.

Sow reproductive and progeny growth performance when fed Pichia guilliermondii yeast postbiotic: systematic review and meta-analysis.

Previous research suggested that feeding sows with a product containing an inactivated strain specific Pichia guilliermondii yeast postbiotic (PG; Citristim, ADM Animal Nutrition, Quincy, IL) has the potential to support fecundity, and progeny performance at birth, weaning, and after weaning. To summarize these effects, a systematic review followed by a meta-analysis was carried out to determine the effects of feeding sows with PG during gestation and lactation on reproductive the performance of sows and the growth of progeny after weaning. All experiments included were randomized trials reporting side-by-side comparisons of an appropriate control (CON) and the CON with the inclusion of PG. The effects of PG inclusion in sow diets were evaluated using the raw mean difference and effect size calculations. Analysis included seven trials for sow reproductive and litter performance until weaning, and eight trials for progeny performance after weaning. The risk of publication bias was assessed by funnel plots. In the case of publication bias, the Trim and Fill method was used. Heterogeneity was assessed using I 2 statistics. Sows fed PG during gestation and lactation had more piglets born alive (BA), BA + stillborn, and BA + stillborn + mummies (P < 0.001). The individual birth weight of the piglets was not affected by the supplementation (P = 0.835). As a result, litter weight at birth was greater in sows-fed PG (P < 0.001). Piglets born from PG-fed sows tended to be weaned 0.34 d younger than those from CON-fed sows (P = 0.060). Twenty-one-day adjusted pig weight at weaning tended to be lighter by 0.122kg in the PG sow group (P = 0.069); however, litter weight at weaning adjusted to 21 d remained similar across groups (P = 0.516). The number of piglets weaned and mortality-adjusted number of piglets weaned per sow were greater in PG than in CON sows (P < 0.023). A carryover effect was observed for progeny of PG-fed sows after weaning. Piglets born from PG-supplemented sows had greater weight gain (P = 0.030) and tended to have a better survival rate (P = 0.055) until the end of the nursery phase. These results indicate that feeding PG to sows during gestation and lactation consistently and significantly improves not only the performance of sows at farrowing but also performance of the progeny after weaning.

Burlap and buddies: the effects of social enrichment (preweaning mixing) and object enrichment (burlap) on piglet performance, behavior, and welfare in the preweaning environment.

When weaned in commercial operations, piglets are not only separated from their sow but also mixed with unfamiliar pigs in an unfamiliar environment with a new diet. These abrupt changes can be stressful for piglets, often having negative welfare consequences. Our objective was to study the effects of early-life preweaning socialization and object enrichment in the preweaning environment. We compared piglet performance, behavior, and welfare across six treatments that combined multi-litter group size (1 vs. 2 vs. 4 litters) and burlap (yes vs. no). We recorded piglet behavior and lesion-scored sows and piglets. Normal conforming data, expressed per experimental unit (and behavior data were averaged over time), were analyzed by ANOVA. When given the opportunity in the sow barn, piglets in multi-litter groups socialized with other litters. Burlap use (P = 0.08) was observed in < 5% of the observations but tended to increase in mixed litter groups. Cross-sucking was observed in ~12% of the observations within mixed litter groups and tended to increase with mixed group size (P = 0.08). While there was no difference in the proportion of piglets nursing (P > 0.10), piglets were less active in the single crate groups and most active in the groups of two litters mixed (P = 0.03). Additionally, observed piglet/sow biting behaviors did not differ between treatments; however, piglet-piglet biting (P = 0.07), and pen object manipulation (P = 0.07) tended to be observed more frequently in non-enriched groups. Piglet displacements were observed more often in non-enriched groups around the pen (P = 0.03) but tended to be observed more often in enriched groups at the teat (P = 0.07). Preweaning socialization and object enrichment had no impact on the average number of piglets weaned per sow or total piglet mortality (P > 0.10). However, the proportion of laid-on piglets decreased as the number of mixed litters increased (P = 0.02). The average number of lesions per piglet did not differ between treatments. Although the final lesion scores of sow teat and udder condition did not differ between treatments (P > 0.10), sow udder scores tended to worsen more in the single litters than in the mixed litters (P = 0.08). Overall, social and object enrichment allows piglets to socialize at a younger age and to redirect their attention toward an object (burlap) which does not negatively impact piglet or sow performance, or behavior, and may improve piglet welfare around weaning.