Backfat Loss Research Articles

Effect of dietary salicylic acid supplementation on performance and blood metabolites of sows and their litters.

The core intention to undertake this experiment for a period of 21 days is to evaluate the effect of salicylic acid (SA) supplemented diet on the performance and blood metabolites of sows and their litters. Sows weighing 208.5 ± 18.34kg and their neonates were used. From day 114 of gestation to 21st day of lactation(weaning), ten multiparous sows (n = 5/treatment) (Landrace x Yorkshire) were assigned randomly into one of two treatments: CON (basal diet) and TRT (CON + 0.05% SA). There was no significant difference in the body weight, backfat thickness, backfat loss, and body condition score in SA treated sows compared to sows fed the CON diet. However, the bodyweight of sow was dramatically reduced by an average of 16kg from farrowing to weaning time. The dietary inclusion of SA in the sow diet slightly improved the survival rate (p = 0.065) and showed a higher body weight (p = 0.009) in piglets. However, there was no significant difference in red blood cell, Fe, Hematocrit, and Hb concentrations between CON and TRT sows’ groups, but the total iron-binding capacity (TIBC) was significantly reduced in sows from the TRT group compared with the CON group from the beginning to weaning. The outcome of this trial shows that dietary addition of SA on sows diet from early lactation could increase the birth weight and TIBC of neonates at the end of the trial.

Effect of Saccharomyces cerevisiae boulardii on sows' farrowing duration and reproductive performance, and weanling piglets' performance and IgG concentration.

We studied the effects of Saccharomyces cerevisiae boulardii CNCM I-1079 (LSB) supplemented to lactating sows on reproductive traits and farrowing duration and to piglets from day 7 of life on post-weaning performance and IgG concentration. Ninety-six Landrace × Yorkshire sows started the trial 5 days before the expected farrowing date. Sows were distributed into 2 groups according to parity number and backfat thickness: control (CON: regular lactation diet) and LSB (CON + LSB at 2 × 109 colony forming units [CFU]/kg of feed). Seven days after birth, litters were randomly selected from each group and supplemented creep feed with or without LSB at 2 × 109 CFU/kg. At weaning, piglets from CON sows were shifted to a commercial farm and allocated to 14 pens in groups of 25 piglets/pen according to the creep feed supplemented during lactation. Piglets followed a 3-phase feeding program: creep, pre-starter and starter, with or without LSB at 2 × 109 CFU/kg LSB in creep and pre-starter, and 1 × 109 CFU/kg LSB in starter. The piglets were vaccinated against classical swine fever on days 41 and 72 of life. One day before each vaccination and at the end of the trial, blood samples were collected from 15 randomly selected piglets per treatment and assessed for total IgG. Supplemented sows with non-supplemented litters displayed the lowest backfat thickness loss during lactation (p < 0.05). The LSB supplementation shortened farrowing duration (p < 0.05) and increased feed intake (p < 0.05) during the first week of lactation. The LSB-fed piglets were heavier at the end of creep (p < 0.05), pre-starter (p < 0.05), and the trial (p < 0.05); grew faster during creep (p < 0.05), starter (p < 0.05), and overall (p < 0.05); and displayed an improved feed conversion ratio during creep (p < 0.05). Total IgG content was higher at days 40 (p < 0.05) and 71 (p < 0.05) in LSB-fed piglets. We conclude that supplementing sows with Saccharomyces cerevisiae boulardii CNCM I-1079 from late gestation until weaning shortens farrowing duration, increases feed intake, and minimizes backfat losses during lactation. When supplemented to piglet diet, post-weaning performance is improved. This improvement observed could be linked to a better immune status, as suggested by the higher IgG.

Activated crystalline silicon dioxide mitigates weight loss in lactating sows

This study investigated activated crystalline silicon dioxide (SIL) supplementation in late pregnancy and lactating sows on reproductive parameters as well as the performance of suckling piglets. Eighty sows were assigned to two groups: control (CON, n = 40), and activated crystalline SIL (n = 40). Both treatments received identical basal diets, without (CON), or with 0.3 kg of activated SIL/ton at day 111 of pregnancy up to day 21 of lactation. The sows were evaluated at day110 of gestation and at day 21 of lactation for individual body weight (BW), backfat (BF), average daily feed intake (ADFI), percentage of BW and BF loss, and milk production. The litter was evaluated for size and BW at birth, and at 21 d old, likewise the preweaning survival percentage. At day 21 lactation, the SIL sows were 2.39% heavier than the CON group. The sows also had an increase of 5.05% in milk yield compared to the CON sows. In addition, SIL sows showed lower weight loss compared to CON sows. The weaned piglets from SIL sows had an increase of 4.43% in BW compared to CON sows. In conclusion, supplementation of 0.03% of activated crystalline SIL applied to late pregnancy, and to lactating sows reduced weight loss and marginally improved the milk yield and BW of piglets at weaning. Highlights The activated crystalline silicon dioxide (SIL) in diets from late pregnancy to lactation reduced body weight loss of sows. Sows that received activated crystalline SIL in late pregnancy and lactating period trended to improve the milk yield in 5.05%. The piglets from sows fed activated crystalline SIL tended to enhance 4.43% in body weight at 21-d old.

Effects of restricting energy during the gilt development period on growth and reproduction of lines differing in lean growth rate: responses in reproductive performance and longevity.

Longevity and reproductive performance are economically important traits in the swine industry that are largely influenced by nutrition and other environmental factors. Reproductive performance and longevity through 4 parities was assessed in gilts of 2 genetic lines developed on ad libitum access to feed or restricted to 75% of ad libitum intake. A total of 661 gilts were used in a 2 × 2 factorial with half of the gilts allocated to an ad libitum diet (AL; n = 330), while the other half were energy restricted by 25% (R; n = 331) from 123 to 235 d of age. All gilts were sired by an industry maternal line. Dams of the gilts were from either a Large White (W) by Landrace (L) industry maternal line or Nebraska Selection Line 45X, producing gilts designated as W × L (n = 355) and L45X (n = 306), respectively. Daily estrus detection began at 140 d of age to obtain age at puberty (AP). Gilts (n = 510) were mated on their second or later estrus, beginning at 240 d of age. Sow weight and backfat were recorded at 110 d of gestation and weaning of each parity. Number of live-born, stillborn, and mummified pigs per litter and piglet birth and weaning weights were recorded through 4 parities. More L45X than W × L and more AL than R gilts reached puberty by 230 d of age (P < 0.01). Dietary treatment did not affect probability to produce parities 1 to 4 or any litter trait analyzed. The L45X females tended to be more likely to produce parities 1 (P < 0.08) and 3 (P < 0.06), while W × L had heavier litters at birth (P < 0.01) and weaning (P = 0.01). Treatment by parity interactions (P < 0.01) existed for weight and backfat prior to farrowing and backfat at weaning, and weight at weaning exhibited a line by treatment by parity interaction (P = 0.04) as R sows had lower weights and backfats in earlier parities, but caught up to AL sows in later parities. A treatment by parity interaction (P < 0.01) was also present for backfat loss from farrowing to weaning as R gilts lost less backfat than AL in parities 1 and 2, but more in parities 3 and 4. No significant differences were detected between lines or treatments for lifetime production traits. The populations of pigs and data presented here provide a framework for a diverse array of further studies. Alternative approaches to restrict energy have been assessed in addition to methods of marker-assisted and genomic selection for improvement of litter size and sow longevity.

Dietary fibre supplemented pre-mating diets do not improve follicle development and litter characteristics in primiparous sows

Piglet birth weight is an important factor for their survival and growth. As the pre-mating diet influences the sow's metabolic state, this may have an impact on follicle development after weaning and subsequent piglet birth weight. We investigated the pre-mating effect of dietary fibre (DF; sugar beet pulp (SBP) and microfibrillated cellulose (MFC)) on metabolic hormones and metabolites (IGF-1, non-esterified fatty acids (NEFA), creatinine, urea and leptin), follicle development, and litter characteristics at subsequent farrowing in 58 hyper-prolific primiparous sows farrowing 16.5 ± 0.4 piglets used in three consecutive batches. We supplemented commercial diets (CON) with SBP and MFC during the last week of lactation and the weaning-to-oestrus interval (WEI). We measured follicle diameters with ultrasound and collected preprandial blood samples at weaning, 3 days after weaning, and at oestrus. A tendency for higher average daily feed intake (ADFI; 5.69 v. 6.61 kg/day, P < 0.07) and significant lower backfat (BF; 1.1 v. 0.2 mm, P < 0.05) loss were observed in SBP sows than in MFC sows during one week before weaning. Total dietary fibre (TDF) intake during the last week of lactation was higher in SBP sows than in CON sows, whereas TDF intake in SBP sows was similar to MFC sows (775.0 vs. 900.6 vs. 840.9 g/day, respectively, for CON, SBP and MFC, P < 0.05). Creatinine concentration at weaning was higher in SBP sows than in MFC sows (162.9 v. 136.6 mmol/L, P < 0.001). Other hormones and reproductive parameters were not affected by pre-mating diets. At subsequent farrowing, there was no difference in litter characteristics (P > 0.05). In our study, the different types of DF fed pre-mating affected feed intake and body protein mobilization during lactation. However, the supplementation of DF before mating did neither improve follicle development nor litter characteristics in the hyper-prolific sows.

Effects of Dietary Monoglyceride and Diglyceride Supplementation on the Performance, Milk Composition, and Immune Status of Sows During Late Gestation and Lactation.

Monoglyceride and diglyceride (MGDG) have antiviral and antibacterial properties and act as emulsifiers to increase dietary lipid digestibility. The primary aim of this trial was to investigate the effects of dietary MGDG supplementation on the reproductive performance and health status of sows during late gestation and lactation. One hundred sows (Landrace × Large White, mean parity of 4.59) were randomly allocated to groups receiving two different diets with 4% soybean lipids or 4% MGDG from day 85 of gestation to day 21 of lactation. Milk samples were collected on the day of farrowing (colostrum) and on day 14 of lactation, and blood samples were collected from the sows on days 0, 14, and 21 of lactation. Compared with control sows, sows fed MGDG showed no significant differences in reproductive performance (P > 0.05), but sow back fat thickness loss decreased during lactation (P < 0.05). There was a significant decrease in TNF-α concentrations in colostrum in the MGDG-supplemented sows compared with that in the soybean lipid-supplemented sows (P < 0.05). Dietary MGDG supplementation decreased sow plasma IL-8 concentrations on day 0 of lactation and IL-18 concentrations on days 14 and 21 of lactation (P < 0.05). Administration of MGDG increased the glucose and total cholesterol concentrations in sow plasma on day 14 and day 21, respectively (P < 0.05). The findings in this study suggest that MGDG supplementation could be effective in reducing back fat loss, decreasing inflammatory factor levels, and controlling total cholesterol (TCHO) concentrations during lactation.

Use of paracetamol in sows around farrowing: effect on health and condition of the sow, piglet mortality, piglet weight and piglet weight gain

BackgroundPain and fever in the periparturient period can lead to prolonged farrowing and can slow down the recovery of the sow, which will have an effect on the vitality and survival of the piglets. This study investigated the use of orally administered Paracetamol (Pracetam- CEVA) in sows in the periparturient period.ResultsMortality did not differ in piglets during the first week, or during total lactation (P > 0.10). No difference was found in weight or weight gain of the piglets during lactation. The coefficient of variation of piglet weight was smaller in the Paracetamol (Pm) group at day 7, day 14 and at weaning, but not at birth. So, the variation within litters was smaller in the Pm- treated sows, in comparison with the Control (C) litters. No difference in mean IgG concentration was found between treatments, but the coefficient of variation was too high (> 40) in 50% of the C litters and not in Pm litters. The Pm- treated sows lost less backfat than the C- sows. No effect was found on the body temperature of the sows, but fever was rare in both groups.ConclusionParacetamol results in less variation of body weight of piglets during lactation, seems to have a potential effect on the distribution of IgG within litters and has a positive effect on backfat loss. The effects of Paracetamol might be even more pronounced in farms with high piglet mortality (this farm only 8%) or with a high incidence of agalactia, fever after farrowing or piglet diarrhoea, which was not the case in this farm. Paracetamol is a promising product for increasing the welfare in lactating sows and optimising production in the farrowing stable.

57 The Impact of Functional Teat Number on Piglet Survival and Sow Efficiency

Abstract Pre-weaning mortalities have become a pressing issue in modern swine production. Litter size at birth has greatly increased through direct genetic selection. Unfortunately, little emphasis was placed on improving functional teat number, resulting in a nutrient access shortage. Therefore, a total of 750 sows consisting of three genetic lines in a commercial barn in Nebraska, USA, were used to evaluate the impact of functional teat number on piglet survival. Teat traits recorded at farrowing included total teat number (TT), functional teat number (FT), and non-functional teat number (NFT); with population means of 14.84 (1.21), 14.55 (1.30), and 0.28 (0.56), respectively. Production traits recorded included total number born (TNB), wean number (WN), total pre-weaning mortality (PWM), and post-cross foster mortality (CFPWM). The lm function within RStudio was used to estimate regressions, with parity and piglets placed (PP) used as covariates for WN and CFPWM, and parity, PP, and TNB for PWM. One additional FT increased WN (P &amp;lt; 0.01; 0.33), and reduced PWM (P &amp;lt; 0.01; -3.04%) and reduced CFPWM (P &amp;lt; 0.01; -3.71%). A subset of 274 sows were used to determine the effects of increasing functional teats on sow and piglet efficiency. Additional traits recorded included sow average daily feed intake (ADFI), backfat loss (BF) and average piglet weaning weight (WW). Parity, ADFI, backfat-entry, and WN were used as covariates for BF; parity, backfat-entry, and WN for ADFI; and parity, PP, ADFI, and WN were used for estimating WW. Regression estimates showed that an additional functional teat had no significant impact (P &amp;gt; 0.05) on ADFI, BF, or WW. Taken together, these results suggest that improving functional teat number does not impact ADFI or BF for sows and does not influence average piglet weaning weight, but it does decrease PWM resulting in more pigs weaned per litter.

Effects of Amaranthus hypochondriacus supplementation during gestation and lactation on the apparent total tract digestibility of nutrients, lactational feed intake, and litter performance in sows.

The purpose of this study was to investigate the effects of Amaranthus hypochondriacus (AH) inclusion in the diets of gestating and lactating sows on the lactational feed intake, nutrient digestibility, and growth performance of suckling piglets. During gestation, 40 multiparous Landrace sows were restrictively fed with either a control diet or a diet including 30% AH. Both diets had similar levels of digestible energy and crude protein, but the 30% AH diet had higher crude fibre levels than the control diet. After breeding, lactating sows were fed ad libitum with one of two isoenergetic and isonitrogenous diets, either a control diet or a diet containing 10% AH. In gestating sows, AH supplementation was found to be associated with decreased digestibility of crude protein and dry matter (p < .001), resulting in lesser backfat depth (p < .001). However, in lactating sows, AH supplementation had little effect on digestibility and milk composition; moreover, it increased the feed intake (p < .001) and decreased backfat loss (p < .001) in sows. On the 21st day of lactation, suckling piglets in AH group showed significantly greater average daily gains (p < .001), and average body weight and litter weight significantly increased compared with sows fed the control diet. In conclusion, AH‐supplementation increased lactational feed intake in sows and improved the growth performance of suckling piglets.

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.

Productive effects of a colostrum-oriented amino acid dietary supply for sows in transition from gestation to lactation

In sows, the synthesis of the colostrum begins several days before farrowing and the different amino acid composition of colostrum compared to milk can justify the hypothesis of different dietary requirements to produce it. The objective of the study was to test the enrichment with threonine (Thr), tryptophan (Trp) and valine in the peripartum diet of sows on the quality of colostrum, health and growth of piglets, and the variations of backfat and lean thickness and the faecal microbiome of sows. Ninety-nine sows were divided into two groups, balanced by parity number and fed: (1) the standard formula used on late gestation to early lactation (CON; 50 sows; (2) CON added with 0.074% L-Thr, 0.034% L-Trp and 0.077% L-valine (TRT; 49 sows). The number of pigs born alive and their average live weight, the number of weaned pigs, their growth and the mortality on d1 did not change with the diet, but the percentage of total dead piglets was reduced when sows were fed TRT (−3.5%, p = .049). Backfat loss of sows in lactation was marginally reduced (p = .097). The IgA content of colostrum increased with TRT, but not protein, fat, lactose or urea. Bacterial richness (Chao1) decreased in faeces of sows at the end of lactation with TRT, but not bacterial diversity. Selenomonas and Bacillus were more abundant in CON and TRT, respectively. Adjusting the amino acid profile of the feed provided in the transition phase between final gestation and early lactation to the colostrum profile could improve the survival of suckled piglets. Highlights The amino acid profile of colostrum differs from that of milk. The pre-weaning mortality can be decreased by feeding sows a diet with an amino acid profile closer to that of colostrum. Raising the dietary ratio of threonine (Thr), tryptophan (Trp) and valine to lysine (Lys) in the peripartum diet of sows improves the IgA content of colostrum.

277 Effects of timing and amount of feed prior to farrowing on sow and litter performance under commercial conditions

Abstract A total of 727 mixed parity (mean=3.8) sows were used to evaluate the effects of timing and amount of meals before farrowing on sow and litter performance. Upon entry to the farrowing house (d 113), sows were blocked by weight within parity and allotted to one of three feeding management treatments until farrowing: 1) 2.7 kg lactation diet (1.15% SID lysine and 2,153 Kcal/kg NE) once daily at 0700 h; 2) 4 daily meals of 0.67 kg (0100 h, 0700 h, 1300 h, 1900 h); 3) ad libitum lactation diet and encouraged to consume feed at 0100 h, 0700 h, 1300 h, and 1900 h. Data was analyzed using the lme function (lmer package of R, version 3.5.2). Feeding sows ad libitum before farrowing tended to reduce sow body weight loss (P=0.077) and reduce backfat loss (P=0.003) from entry to weaning compared to sows fed 4 daily meals, with sows fed once daily intermediate. Litter gain from 24 h to weaning tended to be greater (P=0.073) in sows fed ad libitum or 4 times daily prior to farrowing compared to sows fed one meal. Piglet weaning weight increased (P=0.050) in sows fed ad libitum before farrowing, compared to those fed one meal, with those fed 4 times daily intermediate. There was no evidence for difference in farrowing duration, stillborn rate, colostrum yield, or 24 h piglet survival regardless of treatment. However from 24 h to weaning, sows fed one daily meal had higher (P=0.012) percentage of fall-behind pigs compared to sows fed ad libitum, and increased (P=0.027) preweaning mortality compared to sows fed four daily meals, resulting in reduced (P=0.006) weaned percentage compared to sows fed four daily meals. There was no evidence for a negative impact when sows were fed ad libitum from 2 to 3 days before farrowing.

Bacillus subtilis and Enterococcus faecium co‐fermented feed regulates lactating sow's performance, immune status and gut microbiota

Fermented feed (FF) is widely applied to improve swine performance. However, the understandings of the effects of FF on the immune status and gut microbiota of lactating sows and whether probiotics are the effective composition of FF are still limited. The present study aimed to investigate the performance, immune status and gut microbiota of lactating sows fed with a basal diet supplemented with Bacillus subtilis and Enterococcus faecium co-fermented feed (FF), with the probiotic combination (PRO) of B. subtilis and E. faecium and control diet (CON) as controls. Compared with the CON group, FF group remarkably improved the average daily feed intake of sows and the weight gain of piglets, while significantly decreased the backfat loss, constipation rate of sows and diarrhoea incidence of piglets. The yield and quality of milk of sows in FF group were improved. Besides, faecal acetate and butyrate were promoted in FF group. Additionally, FF increased the level of IgG, IgM and IL-10 and decreased the concentration of TNF-α in serum. Furthermore, FF reduced the abundance of Enterobacteriaceae and increased the level of Lactobacillus and Succiniclasticum, which were remarkably associated with growth performance and serum immune parameters. Accordingly, microbial metabolic functions including DNA repair and recombination proteins, glycolysis and gluconeogenesis, mismatch repair and d-alanine metabolism were significantly upregulated, while amino acid metabolism was downregulated in FF group. Overall, the beneficial effects of FF were superior to PRO treatment. Altogether, administration of FF during lactation improved the performance and immune status, and modulated gut microbiota of sows. Probiotics are not the only one effective compound of FF.

Effects of dietary levan-type fructan on growth performance, blood profiles, fecal noxious gas emissions, and litter performance in lactating sows

In total, 28 multiparous sows (n = 7) and their litters were used to determine the effects of levan-type fructan supplementation on growth performance, nutrient digestibility, blood profiles, and fecal noxious gas emissions. The dietary treatments included (1) CON, basal diet; (2) FC1, CON + 0.1% fructan; (3) FC2, CON + 0.2% fructan; and (4) FC3, CON + 0.3% fructan. No significant differences were observed (P &gt; 0.05) in body weight (BW), average daily feed intake, or back fat loss in lactating sows among treatments. However, blood lymphocyte concentrates were higher (P &lt; 0.05) in sows fed levan-containing diets than in those fed the CON diet. Weaning BW and overall average daily gain (ADG) of piglets in the FC3 treatment were higher (P &lt; 0.05) than piglets in the CON treatment. Blood lymphocytes and nutrient digestibility of sows, as well as the weaning BW and the ADG of piglets were increased linearly (P &lt; 0.05) as the concentration of levan increased in the diet. The diarrhea score of piglets and the fecal gas emissions of sows decreased linearly (P &lt; 0.05) as dietary levan increased. In conclusion, levan supplementation did not affect feed intake or decrease back fat loss of lactating sows, but it improved nutrient digestibility and immune ability, decreased fecal noxious gas emissions of lactating sows, and it improved growth performance and reduced diarrhea in piglets.

Effects of free feeding time system and energy level to improve the reproductive performance of lactating sows during summer.

The reproductive performance of lactating sows was investigated by using different feeding methods including conventional feeding (CF, 3 times/d) or free feeding (FF), and different dietary energy level including low energy (LE: 3,300) or high energy (HE: 3,400 kcal/kg) during the hot season. A total of twenty-eight crossbred (Yorkshire × Landrace) sows were distributed into four treatments as a 2 × 2 factorial arrangement. Sows in the FF group showed lower body weight and backfat loss (p < 0.05) compared with the CF group. Backfat loss during lactation was lower (p < 0.05) in sows fed HE diet than in that fed LE diet. There were no significant differences in litter survival rate and weaning to estrus interval, but the litter weight at weaning was improved (p < 0.05) in FF and HE sows. Hence, it is concluded that using the free-feeding system or increased dietary energy density leads to improved sow performance during hot ambient temperature.

Effects of timing and size of meals prior to farrowing on sow and litter performance.

A total of 727 mixed parity (µ = 3.8) sows were used to evaluate the effects of timing and size of meals before farrowing on sow and litter performance. Upon entry to the farrowing house (day 113), sows were blocked by weight within parity and allotted to one of three three feeding management strategies until farrowing: (1) 2.7 kg lactation diet (1.15% standardized ileal digestible lysine and 2,153 kcal/kg net energy) once daily at 0700 hours; (2) four daily meals of 0.67 kg (0100, 0700, 1300, and 1900 hours); (3) ad libitum lactation diet and encouraged to consume feed at 0100, 0700, 1300, and 1900 hours. After farrowing, all sows were provided lactation diets fed on an ad libitum basis until weaning. Data were analyzed for treatment effects within parity category in a mixed model with block as a random effect. Feeding sows ad libitum before farrowing tended to reduce sow body weight (BW) loss (P = 0.077) and reduce backfat (BF) loss (P = 0.003) from entry into the farrowing house until weaning compared with sows fed four daily meals, with sows fed once daily intermediate. Litter gain from 24 h to weaning tended to be greater (P = 0.073) in sows fed on an ad libitum basis or four times daily prior to farrowing compared with sows fed one meal. Piglet weaning weight increased (P = 0.050) in sows fed on an ad libitum basis before farrowing, compared with those fed one meal, with those fed four times daily intermediate. There was no evidence for difference in farrowing duration, stillborn rate, colostrum yield, or 24 h piglet survival regardless of treatment. However, from 24 h after farrowing to weaning, sows fed one daily meal prior to farrowing had an increased (P = 0.012) percentage of fall-behind pigs compared with sows fed on an ad libitum basis, and increased (P = 0.027) preweaning mortality compared with sows fed four daily meals, resulting in reduced (P = 0.006) weaned percentage compared with sows fed four daily meals. There was no evidence for difference (P > 0.10) in subsequent reproductive performance regardless of treatment. In conclusion, when sows were fed on an ad libitum basis from 2 to 3 d, before farrowing there was an observed improvement in sow BW and BF maintenance during lactation, and piglet weaning weight during lactation. Increased frequency of meals prior to farrowing improved the survival of pigs to weaning compared with sows fed a single meal prior to farrowing.

Effects of soybean meal concentration in lactating sow diets on sow and litter performance and blood criteria.

A total of 131 sows (Line 241; DNA, Columbus, NE) were used in a study to evaluate the effect of increasing soybean meal concentration in lactating sow diets on sow and litter performance. Sows were blocked by body weight (BW) within parity on day 112 of gestation and allotted to one of three treatments of increasing dietary soybean meal (25%, 30%, or 35% of the total diet). Diets were formulated to 1.05% standardized ileal digestible lysine (Lys) with L-Lys HCl decreasing as soybean meal increased. All other amino acids and nutrients were formulated to meet nutrient requirement recommendations. Diets were fed from day 112 of gestation until weaning (day 20 ± 2). Litters were cross-fostered up to 48 h after farrowing to equalize litter size. Increasing soybean meal concentration increased (linear, P = 0.017) sow BW loss and tended to increase (quadratic, P = 0.052) sow backfat loss from farrowing to weaning. Sow average daily feed intake (ADFI) from day 0 to 7 was similar (P > 0.10) across dietary treatments. However, from day 7 to 14, 14 to weaning, and overall, ADFI decreased (linear, P = 0.01) as soybean meal concentration increased. Despite the linear response in ADFI, the greatest decrease was observed as soybean meal concentration increased from 30% to 35% of the diet. There was no evidence for difference (P > 0.10) in wean-to-estrus interval, litter size, litter weight, or litter weight gain between dietary treatments. Sow serum urea nitrogen concentrations taken on day 14 of lactation increased (linear, P = 0.001) as soybean meal concentration increased. There was no difference (P > 0.05) for sow creatinine concentration, regardless of dietary treatment, suggesting that the increased urea nitrogen was a reflection of the increased dietary crude protein as opposed to increased protein catabolism. In summary, sow feed intake decreased and weight loss increased as soybean meal concentration of the diet increased, with the greatest decrease observed at 35% of the total diet. Although there were no differences in litter performance, it appeared that 35% soybean meal in the lactation diet negatively affected feed intake.

Effect of backfat thickness during late gestation on farrowing duration, piglet birth weight, colostrum yield, milk yield and reproductive performance of sows

Sow milk is important for the survival and growth of suckling piglets. The reserved backfat of sows during late gestation may influence foetal development and milk synthesis. We investigated the effect of backfat thickness of sows at 109 days of gestation on farrowing duration, piglet birth weight, colostrum yield, milk yield and reproductive performance, using 73 sows and 1,291 piglets. Backfat thickness was measured when the sows entered the farrowing house at 109 days of gestation, using A-mode ultrasonography, and sows were classified into three groups: LOW (≤12.5 mm, n = 24), MODERATE (13 to 15 mm, n = 30) and HIGH (≥15.5 mm, n = 19). Sow parameters included backfat thickness at 10, 17 and 21 days postpartum, backfat loss during lactation, farrowing duration, total number of piglets born per litter (TB) and number of piglets born alive per litter (BA), proportion of stillborn piglets (SB) and mummified foetuses per litter (MM). Piglet parameters consisted of the birth interval and body weight of the piglets at 0,1,3,10 and 17 days postpartum. Colostrum intake of the piglets, colostrum yield and milk yield from days 3–10 and 10–17 of lactation were calculated and compared among groups of sows with different backfat thickness at 109 days of gestation. Farrowing duration and birth interval were 275.0 ± 187.5 and 14.8 ± 27.1 min, respectively. Both the duration of farrowing and the birth interval did not differ among sows with LOW, MODERATE and HIGH backfat thickness (P>0.05). Piglet weight at birth, TB, BA and MM did not differ among groups (P>0.05). However, SB in sow with LOW backfat thickness at 109 days of gestation was higher than sows with MODERATE (P = 0.024) backfat thickness. The proportion of stillborn piglets per litter in sow parities 3 to 6 was higher than in parities 1 and 2 (P<0.05). The highest SB was observed in sow parities 3 to 6 with low backfat thickness. Milk yield of sows between 3 and 10 days of lactation increase as backfat thickness at day 109 of gestation increased (r = 0.32, P = 0.008). However, backfat thickness at 109 days of gestation was negatively correlated with backfat loss during lactation (r=-0.42, P<0.001). Backfat thickness increase by 1.0 mm at day 109 of gestation resulted in an increased milk yield between 3 and 10 days of 271 g per day (P = 0.008). Backfat thickness of sows at 109 days of gestation influenced milk yield during 3 to 10 days of lactation and SB in sow parity numbers 3 to 6. However, high backfat thickness resulted in a high backfat loss during lactation.

Increased dietary protein for lactating sows affects body composition, blood metabolites and milk production

Hyper-prolific sows nurse more piglets than less productive sows, putting a high demand on the nutrient supply for milk production. In addition, the high production level can increase mobilization from body tissues. The effect of increased dietary protein (104, 113, 121, 129, 139 and 150 g standardized ileal digestible (SID) CP/kg) on sow body composition, milk production and plasma metabolite concentrations was investigated from litter standardization (day 2) until weaning (day 24). Sow body composition was determined using the deuterium oxide dilution technique on days 3 and 24 postpartum. Blood samples were collected weekly, and milk samples were obtained on days 3, 10 and 17 of lactation. Litter average daily gain (ADG) peaked at 135 g SID CP/kg (P < 0.001). Sow BW and back fat loss reached a breakpoint at 143 and 127 g SID CP/kg (P < 0.001). Milk fat increased linearly with increasing dietary SID CP (P < 0.05), and milk lactose decreased until a breakpoint at 124 g SID CP/kg and 5.3% (P < 0.001) on day 17. The concentration of milk protein on day 17 increased until a breakpoint at 136 g SID CP/kg (5.0%; P < 0.001). The loss of body protein from day 3 until weaning decreased with increased dietary SID CP until it reached a breakpoint at 128 g SID CP/kg (P < 0.001). The body ash loss declined linearly with increasing dietary SID CP (P < 0.01), and the change in body fat was unaffected by dietary treatment (P=0.41). In early lactation (day 3 + day 10), plasma urea N (PUN) increased linearly after the breakpoint at 139 g SID CP/kg at a concentration of 3.8 mmol/l, and in late lactation (day 17 + day 24), PUN increased linearly after a breakpoint at 133 g SID CP/kg (P < 0.001) at a concentration of 4.5 mmol/l. In conclusion, the SID CP requirement for sows was estimated to 135 g/kg based on litter ADG, and this was supported by the breakpoints of other response variables within the interval 124 to 143 g/kg.

Effects of Timing and Amount of Feed Prior to Farrowing on Sow and Litter Performance Under Commercial Conditions

A total of 727 mixed parity (mean = 3.8) sows were used to evaluate the effects of timing and size of meals before farrowing on sow and litter performance. Upon entry to the farrowing house (d 113), sows were blocked by weight within parity and allotted to 1 of 3 feeding management strategies until farrowing: 1) 6.0 lb lacta­tion diet (1.15% standardized ileal digestible lysine and 1,150 kcal/lb NE) once daily at 0700 h; 2) 4 daily meals of 1.5 lb (0100 h, 0700 h, 1300 h, 1900 h); 3) ad libitum lactation diet and encouraged to consume feed at 0100 h, 0700 h, 1300 h, and 1900 h. After farrowing, all sows were provided lactation diet ad libitum until weaning. Data were analyzed for treatment effects within parity category in a mixed model with block as a random effect. Feeding sows ad libitum before farrowing tended to reduce sow body weight loss (P = 0.077) and reduce backfat loss (P = 0.003) from entry into the farrowing house until weaning compared to sows fed 4 daily meals, with sows fed once daily intermediate. Litter gain from 24 h to weaning tended to be greater (P = 0.064) in sows fed ad libitum or 4 times daily prior to farrowing compared to sows fed one meal. Piglet weaning weight increased (P = 0.050) in sows fed ad libitum before farrowing compared to those fed one meal, with those fed 4 times daily intermediate. There was no evidence for difference in farrowing duration, stillborn rate, colostrum yield, or 24 h piglet survival regardless of treatment. However, from 24 h after farrowing to weaning, sows fed one daily meal prior to farrowing had an increased (P = 0.012) percentage of fall-behind pigs compared to sows fed ad libitum, and increased (P = 0.027) preweaning mortality compared to sows fed four daily meals, resulting in reduced (P = 0.006) weaned percentage compared to sows fed four daily meals. There was no evidence for difference (P > 0.10) in subsequent reproductive performance regardless of treatment. In conclusion, when sows were fed ad libitum from 2 to 3 days before farrowing there was an observed improvement in sow body weight and backfat maintenance, and piglet weaning weight during lactation. Increased frequency of meals prior to farrowing improved the survival of pigs to weaning compared to sows fed a single meal prior to farrowing.