Lactation Feed Intake Research Articles

PSV-20 Effects of Enterid™ in Lactating Sow Diets on Sow and Litter Performance

Abstract A total of 196 sows (parity = 2±1.1; farrowed in 5 groups) were used in this study to evaluate the effects of feeding Enterid™ feed additive (a mixture of prebiotics, probiotics, and flavoring compounds, PMI Additives) on sow and litter performance. On day 109 of gestation, sows were moved to farrowing rooms and assigned to one of two dietary treatments, including: control and control + 0.05% Enterid™. Respective diets were fed to the sows from day 109 of gestation to weaning (weaning age: 19±0.13 day). Sow body weight (BW) and backfat thickness were measured at d 109 of gestation, within 24h after-farrow, and at weaning. Sow feed consumption was recorded daily. Individual pig BW was recorded at birth and weaning. A completely randomized design was used to test the effect of diets and ANOVA was performed with mixed models using MIXED procedure in SAS (SAS 9.4, SAS Inc.). Sows fed Enterid™ numerically had greater weaning body weight (BW; 222 kg vs. 217 kg; P = 0.11) and lost less BW (-1.14 vs. -5.38 kg; P = 0.01) and backfat (+0.5 vs. -1.5 mm, P = 0.02) from farrow to weaning compared to the control. In addition, sows fed Enterid™ numerically had greater total lactation feed intake (127 vs 123 kg; P = 0.13) and ADFI (6.64 vs 6.42 kg; P = 0.17). Enterid™ numerically reduced piglet preweaning mortality by 1% (9.15 vs 10.16%). Data of this study suggests that Enterid™ can provide benefits toward improving performance of sows and reducing mortality of preweaning piglets.

Reduced vitamin supplementation with fat-soluble vitamins A, D, and E added at National Research Council requirements may not be adequate for optimal sow and progeny performance

Objective: To evaluate performance and physiological vitamin status of sows and progeny fed 2 vitamin supplementation levels, industry vs reduced (all vitamins reduced with fat-soluble vitamins added at National Research Council recommendations). Materials and methods: Sows (n = 244) were allotted in a randomized complete block design to 1 of 2 vitamin supplementation levels. At weaning, 765 progeny from a subset of sows were allotted to treatments in a 2 × 2 factorial arrangement of two sow and two nursery vitamin supplementation levels with 15 pens/treatment. Performance and vitamin status of sows and progeny were measured from farrowing to nursery exit. Results: Reduced vitamin supplementation reduced sow lactation feed intake (P = .01), hepatic vitamin A (P = .001), and serum vitamin D (P < .001), but did not affect sow body weight or litter performance. Regardless of vitamin levels fed to the sow, progeny fed reduced levels post weaning had decreased circulating (P < .001) and stored (P = .03) vitamin levels and a reduction in average daily gain (P < .001), average daily feed intake (P < .001), gain:feed ratio (P = .002), and body weight (P < .001) at the end of the nursery period compared to progeny fed industry levels. Implications: Reduced vitamin supplementation reduced sow feed intake without affecting sow or litter performance, but decreased circulating and stored vitamin levels in sows could impact long-term reproductive performance. Reduced vitamin inclusion levels in nursery diets reduced performance and serum vitamin concentrations compared to industry vitamin levels.

PSVII-11 Long-term evaluation of dietary OmniGen AF supplementation on reproductive performance and milk composition of sows

Abstract A cooperative study involving 189 litters from 114 sows [initial breeding body weight (BW), 200.8 ± 37.1 kg] was conducted at two experiment stations to investigate the effects of OmniGen AF (OG; Phibro Animal Health Corporation) supplementation in sow diets on reproductive performance and milk composition. Diets were: 1) corn-soybean meal-based control diet that met NRC (2012) requirement estimates or 2) control plus 0.75% OG. A common diet formulation was used by both stations. Sow allotment was balanced for breed, parity, and BW. Sows were allotted to diets at least 21 days prebreeding and were fed the diets continuously at 1.82 kg daily in gestation and ad libitum in lactation. Sow BWs were measured at breeding, prefarrowing, postfarrowing and weaning. Litter size responses were recorded within 24 h postpartum and individual pig weights were measured at birth and weaning. Milk samples were collected twice during lactation on d 5–7 and d 14–17. Supplementation with OG resulted in less (P < 0.05) BW change of sows during lactation (-12.1 vs. -8.2 kg). Total born (12.9 vs. 13.0), live born (11.7 vs. 12.0), and weaned (10.3 vs. 10.5) were similar for control and OG sows, respectively. Sows fed OG-based diets had greater (P < 0.05) litter weight for total born (18.3 vs. 19.3 kg) and weaned (63.2 vs. 67.0 kg), and lactation litter gain (47.8 vs. 50.7 kg). Lactation feed intake for control and OG sows (5.32 vs 5.52 kg, respectively) did not differ. Supplementing sow diets with OG increased (P = 0.057) lactose content (5.78 vs. 5.84%) and reduced (P = 0.047) protein content (4.77 vs. 4.68%) in milk. The results of this study demonstrated that supplemental OG at 0.75% in sow diets reduced weight loss during lactation and improved litter weights with marginal effects on milk composition of sows.

Maternal supplementation with phytogenic additives influenced the faecal microbiota and reproductive potential in sows

Sows undergo physiological stress during gestation and lactation, potentially leading to enteric dysbiosis and reduced reproductive potential. Phytogenic additives (PFs) may improve performance via their antioxidant, anti-inflammatory and antimicrobial properties. This study determined whether the provision of a gestation/lactation diet containing PAs would alter the gastrointestinal microbiota of sows and their piglets, and improve performance. Sows received a commercial diet throughout gestation and lactation (CTR; n = 64), a commercial diet throughout gestation and a diet containing PAs in lactation (CTR-PA; n = 63) or a commercial diet containing PAs in gestation and lactation (PA; n = 90). Sows were weighed and backfat recorded after mating and at entry and exit from the farrowing house and piglets were weighed on days 1 and 21 of life. Faecal samples collected from sows at farrowing house entry and piglets at 21 and 35 d were subjected to 16 S rRNA gene amplicon analysis. The addition of PAs to sow diets resulted in more piglets born (P = 0.03), however, it did not improve the number of liveborn piglets (P = 0.14). There were no differences in sow weight, P2 backfat depth or lactation feed intake observed. PAs had no effect on piglet weight or survival to weaning but did alter the faecal microbiota of sows, and this change was observed in piglets at 21 and 35 d. PA supplementation to sows has the potential to increase litter size, while also potentially influencing gastrointestinal tract health of the sow and piglets reared.

241 Evaluation of a DFM and OA, Alone or in Combination, on Sow Reproductive and Litter Growth Performance

Abstract Forty-seven sows and their progeny were used to determine if feeding gestating and lactating sows a Bacillus licheniformis direct-fed microbial (DFM), an organic acid blend of medium chain and short chain fatty acids (OA), or in combination improves sow lactation feed and water intake, litter growth, and subsequent reproductive performance. On approximately d80 of gestation, sows were fed one of four diets in a 2 x 2 factorial design: 1) gestation control (CON; 0.55% SID Lysine), 2) CON with DFM (1.6x109 CFU/kg of complete feed), 3) CON with 0.4% OA, 4) CON with both DFM and OA. Dietary treatments were also fed throughout lactation (1.00% SID Lysine) starting on approximately d112 of gestation when sows entered farrowing facility. There was a tendency (P = 0.079) for DFM to decrease the amount of sow body weight loss in lactation by approximately 6% compared to sows not consuming the DFM, likely related to DFM sows numerically (P = 0.124) consuming 8.4% more feed during d7-14 of lactation. Sows fed the OA diets had fewer mummies/litter (P = 0.038) compared to diets not containing OA. Sows fed diets with the DFM gave birth to lighter pigs born alive (P = 0.003) compared to non-DFM fed sows, and a tendency for an interaction (P = 0.092) existed where feeding OA+DFM lessened the decrease in born alive BW. There was an interaction tendency (P = 0.133) where sows fed DFM returned to estrus 22 hours sooner than CON, but only 8 hours sooner when sows were fed the OA+DFM diet. In conclusion, feeding a Bacillus licheniformis DFM to sows may decrease pig born alive weight but reduce sow BW loss through 6.4% more lactation feed intake, quickening the return to estrus. Feeding the OA alone or in combination did not improve sow reproductive and litter growth performance in this study, and may require a larger sample size.

124 Effects of Different Feeding Levels Prior to Farrowing on Sow and Litter Performance

Abstract Our objective was to determine the effects of different pre-farrow feeding levels on sow and litter performance. On d 112 of gestation, a total of 309 sows (Camborough; PIC, Hendersonville, TN) were blocked by parity (P1, P2, P3+) and body weight and allotted to one of three treatments in a randomized complete block design. Treatments consisted of different feeding levels, which included: 1) 1.81 kg/d; 2) 2.72 kg/d; and 3) ad libitum access to feed. Sows were fed a corn-soybean meal-dried distillers grains with solubles-based lactation diet containing 3.36 Mcal of ME/kg and 1.17% SID Lys. Sows were weighed and visual BCS and caliper units were recorded at entry into the farrowing room at d 112 of gestation and at weaning. Daily feed intake was recorded from the beginning of the study until weaning. Litters were cross-fostered within treatment within 24-h after farrowing, and litter weights were collected at 12-h post-farrow and at weaning. Data were analyzed using the GLIMMIX procedure of SAS with sow as the experimental unit and block as a random effect. Covariates were used if they significantly improved the model fit. Ad libitum sows had the greatest (P < 0.05) feed intake from d 112 to farrow, followed by 2.72 kg/d and 1.81 kg/d treatments; however, no evidence (P > 0.10) for differences in lactation feed intake were observed. Wean-to-estrus interval was greater (P < 0.05) for ad libitum sows compared to sows fed 1.81 kg/d. Removal plus mortality rate was marginally lower (P < 0.10) for sows fed 2.72 kg/d compared to sows fed 1.81 kg/d. No evidence (P > 0.10) for treatment differences were observed in total born, stillbirth rate, and litter or piglet weight gain during lactation. In conclusion, results from this study do not support increasing feeding levels for sows prior to farrowing starting on d 112 of gestation.

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 dietary fiber supplementation in gestation diets on sow performance, physiology and milk composition for successive three parities

The experiment was conducted to evaluate the effects of dietary fiber supplementation in gestation diets on sow performance, physiology and milk composition for three successive parities. Thirty gilts were assigned randomly to two groups, and fed a basal diet [CON group; 1.10 % soluble fiber (SF), 9.14 % insoluble fiber (ISF)] or a basal diet supplemented with 22.60 g/kg inulin and 181.60 g/kg cellulose [high-fiber (HF) group] during gestation period. The gestation diets provided to sows for three successive cycles averaged 2.28 kg/d from 1 to 112 d for the CON group; and corresponding values for the HF group were 2.75 kg. During lactation and empty, all sows were fed ad libitum a standard lactation diet. Sow body weight (BW) and backfat thickness, litter size and weight, parturition progress, placental weight and lactation feed intake were recorded. In parity 3, plasma samples were collected at gestation day 110 and parturition, and colostrum and milk samples were manually collected on lactation d 0 and 14, respectively. Results showed that averaged over three reproductive cycles, sows fed the HF diet farrowed more piglets born alive (P = 0.049) and litter weight (total born, P = 0.001; born alive, P = 0.001), increased placental weight (P < 0.001), lactation feed intake (P = 0.042), and average weaned pig BW (P = 0.014), and shortened parturition progress (P < 0.05); tended to have higher average pig BW total born (P = 0.092). Reproductive cycle had significant effects (P < 0.05) on sow BW, duration of parturition, placental weight, lactation feed intake, litter size and weight, and average pig BW. An interaction between fiber treatment and reproductive cycle was detected for placental weight. Sows fed the HF diet in parities 2 and 3 had greater placental weight than the other sows (P = 0.007). In addition, sows fed the HF diet had lower (P < 0.05) preprandial low-density lipoprotein and endotoxin concentrations, and greater (P < 0.05) plasma estrogen and lutropin concentrations on d 110 of gestation; had higher plasma oxytocin (P < 0.05) and epinephrine (P < 0.10) levels at farrowing compared with sows fed the CON diet. Colostrum and milk compositions were not influenced by the treatment. Above all, when the daily intake of the basal gestation diet was equalized for both treatments, dietary fiber supplementation to the gestation diet with an equal ISF/SF ratio over three reproductive cycles improved sow and litter performance.

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

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

PSVI-10 Mint oil, yeast cell, and ɣ-tocopherol supplementation in gestation and lactation diets on the antioxidant status of the sow and offspring performance during the suckling period

Abstract Times of high metabolic activity can lead to increased incidence of oxidative stress in gestating and lactating sows which may impact suckling piglet performance. Identifying products that could help alleviate this stress would be beneficial. A study assessed yeast cell, mint oil, and ɣ-tocopherol supplementation in gestation and lactation diets on sow antioxidant status and offspring performance to weaning. A total of 53 sows and gilts (206.2 ± 35.3 kg at breeding) were assigned to one of 4 diet regimens: Control (CON), control + yeast cell at 0.15% (YC), control + mint oil at 10 ppm (MO), and control + ɣ-tocopherol at 200 ppm (GT). Diets were provided from breeding through weaning (lactation day 21 ± 2). Control diets were formulated to meet nutrient requirements in gestation (3279 kcal ME/kg, 0.63% SID Lys) and lactation (3279 kcal ME/kg, 1.06% SID Lys). Yeast cell, mint oil and ɣ-tocopherol were added as a top dress once daily. Sow variables evaluated were weight at beginning and end of each period, feed intake, litter characteristics at birth, and antioxidant status in serum, colostrum and milk. Piglet growth during suckling was determined. Data were analyzed as randomized complete block and Tukey’s adjustment as means separation test. Maternal diet had minimal impact on gestation or lactation feed intake or sow body weight. There was no effect on litter size or piglet birth weight. Piglets from GT-fed sows tended to be heavier at weaning than YC piglets due to differences in daily gain. Glutathione content in colostrum and d14 milk samples did not differ by maternal treatment. D14 milk Glutathione content was 40%, 59%, 62%, and 51% greater in CON, YC, MO, and GT sows, respectively, compared to colostrum. No difference in superoxide dismutase content in serum and d14 milk observed. Inclusion of ɣ-tocopherol in sow gestation and lactation diets enhanced suckling piglet growth; connection to sow antioxidant status remains unclear.

PSVIII-14 Impact of altering Lys:energy ratio during gestation on offspring post-wean growth performance

Abstract Lysine and energy supply in gestation can influence preweaning mortality and sow lactation feed intake but little data exists for the impact on offspring post-weaning performance. A study evaluated the effects of dietary Lys:energy during gestation on offspring performance from weaning until market. Both primiparous and multiparous females (n=59 in 2 groups) were blocked by parity, balanced by weight and allotted to one of three gestation feeding regimens: 1.50 g SID Lys/Mcal ME (Control), 1.50 g SID Lys/Mcal ME from d2–89 and 2.11 g SID Lys/Mcal ME from d90–110 d of gestation (PF1) and 1.25, 1.07, and 0.88 g SID Lys/Mcal ME from d2–89 for gilts, parity 1 and parity 2+, respectively and 2.11 g SID Lys/Mcal ME from d90–110 d of gestation (PF2). Offspring (n=682) were weaned into 40 pens by maternal treatment (n=13-15 pigs/pen, mixed gender/pen). Pen feed disappearance and individual pig weights were determined at least once each month until market. Animals were marketed by a technician blinded to treatment; to account for potential marketing bias, adjusted d130 weight was calculated. Data were analyzed as a randomized complete block with means separation using Scheffe’s adjustment. The offspring of Control sows had decreased BW at weaning (P &amp;lt; 0.001) versus PF1 offspring and Control offspring had decreased BW (P = 0.001) compared to both PF1 and PF2 at d7 post-weaning. Despite minimal differences in ADG, ADFI, or G:F between treatments, PF2 offspring were heavier (P = 0.02) at market and adjusted d130 weight than Control pigs. While PF1 offspring had similar BW at market than Controls, they spent fewer (138.2 vs. 142.7; P = 0.009) days on feed than Control pigs due to the aforementioned marketing bias. Altered Lys:energy ratio in a single gestation cycle improved offspring post-wean performance.

Effect of the Inclusion of Different Levels of Dietary Cactus (Opuntia ficus-indica) on Gilts’ Biochemical Parameters and Feed Intake during Lactation

Simple SummaryThe digestive and metabolic adaptations suffered by sows during the late gestation-lactation transition cause a decrease in the voluntary feed intake. These conditions favor a negative energy balance, forcing the body to mobilize body reserves to meet their nutritional requirements, which represents an obstacle to expressing their reproductive and productive potential. The supplementation of the sows’ diet with cactus (Opuntia ficus-indica L.) improves the feed intake in lactation due to the favorable modulation of biochemical indicators. However, the optimal addition of cactus to the diet of lactating sows is unknown. In the present study, the increase in the inclusion level of cactus did not linearly increase the feed intake in lactation. However, a linear increase in plasma insulin and osteocalcin concentrations were observed, which led to a decrease in the plasma glucose concentrations. We conclude that the inclusion level of cactus (fresh base) in the diet of lactating sows of 1.0% (with respect to the body weight of the sow) could improve the feed intake in lactation and reduce the loss of body weight of the sow at weaning.The regulation of sows’ metabolic state during the gestation-lactation transition is a requirement for a higher feed intake in lactation, an important aspect in improving animal welfare in current swine production systems. The present study aimed to evaluate the effects of the inclusion of different cactus (Opuntia ficus-indica L.) levels in the diet of gilts during late gestation and lactation on their biochemical parameters and voluntary feed intake during lactation. From day 85 of gestation until weaning, 40 gilts were divided into four groups: GNC (group with no cactus) with a basal diet (BD) only, G1C; group with 1% inclusion of cactus plus BD, G2C; group with 1.5% inclusion of cactus plus BD, and G3C; group with 2% inclusion of cactus plus BD. The dietary cactus supplementation increased the gilts’ feed intake (by 1.04 kg/day on average) during lactation and reduced their weight loss (4.3%) at weaning. The glucose concentrations were higher (range 73.0–83.9 mg/dL) in the GNC. The GNC had the highest triglyceride and cholesterol concentrations at day 100 of gestation. G3C had the highest osteocalcin concentration at day 100 of gestation. The highest feed intake and lowest glucose concentration were achieved with a cactus consumption of 1.04% in lactating gilts.

Impact of feeding low and average birthweight pigs on a weight basis post-weaning on growth performance and body composition

This study aimed to investigate the effectiveness of employing a targeted nutritional regime until slaughter to maintain performance in animals recording high weaning weights. Low birthweight (Low BW; <1 kg) and average birthweight (Av BW; 1.3kg-1.7 kg) pigs were reared on sows exhibiting a high lactation feed intake and, as a result, weaning weights were 7.9 kg and 8.9 kg respectively. Pens containing either Low BW or Av BW animals were then offered either a ‘standard’ (STAND) or ‘feed-to-weight’ (FTW) regime from weaning until slaughter. The STAND regime was reflective of commercial production, where diet transitions were implemented after pre-determined feed levels or time intervals had been reached. In contrast, diet transitions in the FTW regime were carried out when target pen average weights of 12 kg, 18 kg, 22 kg, 45 kg and 75 kg respectively were met. Animal growth, feeding performance and body composition were monitored from weaning until slaughter. As expected, Av BW pigs were heavier than Low BW animals throughout (P<0.001), recording a superior average daily gain (ADG) (P<0.01) and average daily feed intake (ADFI) (P<0.001) at each stage of growth. This resulted in Av BW animals recording a greater carcass weight (P<0.001) and kill-out percentage (P<0.01). DEXA scan analysis showed Low BW animals to exhibit a greater percentage fat (P<0.001) and lower percentage lean (P<0.01) content at week 4 and 10 of age, however birthweight had no effect on these parameters at week 21 (P>0.05). Feeding regime did not affect age or weight at diet transition for Av BW animals for most transitions (P>0.05). However Low BW animals offered the FTW regime were significantly older and heavier than those offered the STAND regime at each transition (P<0.05). The FTW regime increased animal ADG and ADFI compared to STAND pigs from weeks 4 to 10 of age (P<0.05), whilst providing a greater average daily intake of energy and lysine from week 4 to 10 (P<0.05) and week 10 to 17 (P<0.05). This facilitated a greater liveweight in FTW animals from 7 weeks of age through to slaughter (P<0.05). Feeding regime had no effect on kill-out percentage or back-fat depth (P>0.05). Furthermore, DEXA scan results showed total or percentage lean and fat did not differ for FTW or STAND pigs at 10 or 21 weeks of age (P>0.05). In conclusion, feeding Low BW animals on a ‘feed to weight’ basis improved nutrient intake and animal liveweight, likely due to a greater time allowance for digestive development between diet transitions. As such, this approach should be considered for commercial adoption.

Influence of Dietary Fiber on the Development of the Gastrointestinal Tract and the Performance of Gilts

Optimal intestinal development in gilts is a prerequisite for a better farrowing and a higher feed intake in lactation, and these are important facets in improving animal welfare for sows in a high-performance situation. The present study aimed to evaluate the effects of a fiber-rich diet on these topics. Studies with 20 male Topigs castrates and a performance study with 38 female siblings were conducted. Pigs in both of the groups were offered either a control diet (CG) or a high fiber diet (FG) during the second half of the rearing phase (~97 kg BW) until 7 days a.p. At the time of the insemination of the gilts (body weight &gt;170 kg), the castrates were slaughtered and the morphological parameters of the gastrointestinal tract were taken. In the performance study, the feed intake as well as the number and weight of the live and stillborn piglets and the weaning weight of the litters were recorded. The results indicated that the high fiber diet with a greater swelling capacity was beneficial to the development of the gastrointestinal tract (stomach weight CG = 714 g, FG = 812 g, p = 0.007), increased the litter weight (CG =15.9 kg, FG = 20.6 kg, p = 0.045) and resulted in a higher feed intake during lactation overall (CG = 196 kg, FG = 211 kg, p = 0.035).

Impact of sow lactation feed intake on the growth and suckling behavior of low and average birthweight pigs to 10 weeks of age.

Improved genetics in commercial pig production have resulted in larger litter sizes. However this has increased the prevalence of compromised pigs exhibiting inferior birthweights, weaning weights, and lifetime performance. This study aimed to determine the effects of increased sow lactation feed intake on growth of low and average birthweight piglets until 10 wk of age. Low (Low BW; <1 kg) and average (Av BW; 1.3–1.7 kg) birthweight animals were reared in uniformly weighted litters comprising 14 piglets on a foster mother offered either a low (Low FA; max 7.5 kg/d) or high (High FA; max 11 kg/d) feed allowance over a 28- ± 1-d lactation. Piglet performance was monitored from birth until 10 wk of age. Sows offered a High FA consumed 42.4 kg more feed on average than those offered Low FA, resulting in a greater derived milk yield (P < 0.05). Animals of Av BW remained heavier than Low BW pigs throughout the trial (P < 0.05). Piglets reared by High FA sows were heavier at weeks 3, 4, 5, and 7 (P < 0.05) but not week 10 (P > 0.05). Growth rate of piglets relative to their birthweight was significantly greater for Low BW piglets than those of Av BW during lactation (P < 0.001). Piglets reared by sows offered a High FA expressed greater relative growth preweaning (P < 0.05); however, postweaning relative growth for piglets reared on sows offered a Low FA was greater (P < 0.05) suggesting compensatory growth. Neither birthweight nor sow feed allowance significantly affected preweaning mortality (P > 0.05). However, Low BW animals on sows with a High FA recorded half the preweaning mortality of Low BW pigs on sows with a Low FA. During week 1 of lactation, Av BW litters recorded a greater total suckling duration compared to Low BW litters (P < 0.05) but there was no difference in suckling frequency (P > 0.05). During week 3 of lactation, High FA litters displayed a significantly lower suckling frequency (P < 0.05) yet a greater total suckling duration (P < 0.001). Average daily gain was greater for Av BW pigs during weeks 4–7 (P < 0.001) but no difference was recorded between weeks 7 and 10 (P > 0.05). Average daily feed intake was greater for Av BW pigs throughout the nursery period (P < 0.05) but feed–conversion ratio did not differ compared to Low BW pens (P>0.05). In conclusion, offering sows a High FA increased weaning weight of all animals; however, birthweight was the major determinant of postweaning performance.

The Effects of Dietary Supplementation of Saccharomyces cerevisiae Fermentation Product During Late Pregnancy and Lactation on Sow Productivity, Colostrum and Milk Composition, and Antioxidant Status of Sows in a Subtropical Climate.

This study aimed to evaluate the effects of dietary supplementation of Saccharomyces cerevisiae fermentation product (SCFP) during late pregnancy and lactation on sow productivity, colostrum and milk composition, and antioxidant status of sows in a subtropical climate. The study was a 2 × 2 factorial treatment design where the first factor was environmental THI level [Low THI (08:00–19:00: 70.76 ± 0.45, 19:00–08:00: 67.91 ± 0.18, L-THI) or High THI (08:00–19:00: 75.14 ± 0.98, 19:00–08:00: 68.35 ± 0.18, H-THI], and the second factor was dietary treatment (supplemented with or without 3 kg/t SCFP). A total of 120 sows were randomly allotted to the four treatments (n = 30). The feeding trial was conducted from 85-days post-breeding until 21-days post-partum. Compared with L-THI group, sows from H-THI group had lesser individual piglet birth weight, individual piglet weight at weaning, preweaning average daily gain of piglets, average daily feed intake of sows during lactation, and protein percentage in 14-days milk. Additionally, sows from H-THI group had lesser antioxidant status, indicated by lesser serum total antioxidant capacity (T-AOC), and superoxide dismutase (SOD) activity at parturition; lesser serum T-AOC and glutathione peroxidase (GSH-Px) activity at 14-days post-partum, as well as lesser SOD activity in colostrum. Compared with sows fed the control diet, sows fed the SCFP diet had greater number of piglets weaned, litter weight at weaning, and preweaning average daily gain of piglets. Moreover, sows fed the SCFP diet had improved antioxidant status as indicated by higher serum T-AOC at parturition, and lesser malondialdehyde (MDA) content in colostrum and 21-days milk. In conclusion, H-THI negatively affected the productivity, milk composition, antioxidant status, and lactation feed intake of sows. Dietary supplementation of SCFP partially alleviated the adverse effects of H-THI, by improving lactation performance and antioxidant status of sows without influencing reproductive performance and colostrum and milk composition in a subtropical climate.

Effects of Dietary Fiber Sources during Gestation on Stress Status, Abnormal Behaviors and Reproductive Performance of Sows.

Simple SummaryThis study aimed to appraise the effects of two available unconventional dietary fiber resources (resistant starch and fermented soybean fiber) on sows’ reproductive performance through an in vitro-in vivo method to facilitate their application in the rural livestock production systems. Results indicated that inclusion of 5% resistant starch with greater swelling capacity in the gestation diet was beneficial to enhancing postprandial satiety, alleviating stress status, reducing abnormal behaviors and thus lowering the stillbirth rate of sows.Inclusion of fiber in gestation diets is a method for enhancing satiety and reducing abnormal behaviors in restricted feeding sows without providing excess energy. The purpose of this study was to use an in vitro-in vivo method to appraise the effects of two available unconventional dietary fiber resources during gestation on sows’ physio-chemical properties of diets, postprandial satiety, performance, abnormal behaviors, stress status and lactation feed intake under three different dietary treatments: control diet (CON diet), 5% resistant starch diet (RS diet), and 5% fermented soybean fiber diet (FSF diet) with a total of 78 (average parity 5) Landrace × Yorkshire sows. Results showed that swelling capacity was higher in the RS diet than in the CON or FSF diet. Meanwhile, the 48 h cumulative gas production and the final asymptotic gas volume after in vitro fermentation of gestation diets showed an increased trend (p = 0.07, p = 0.09, respectively) in the RS diet versus the CON or FSF diets. While the sows’ litter size, body weight, backfat or weaning-to-estrus interval were not affected (p > 0.05) by the three treatments during gestation, the RS group showed a decline in stillbirth number (p < 0.05) and stillbirth rate (p < 0.01) relative to the other two groups. Meanwhile, the proportion of standing was lower while the sow’s serum concentrations of PYY (peptide YY) and GLP-1 (glucagon-like peptide-1) were higher (p < 0.05) on day 70 of gestation in the RS group than in the CON or FSF group. Compared with the CON group, the RS group showed a downward tendency (p = 0.07) in the sows’ plasma cortisol concentration on day 70 of gestation. A comparison of oxidative and antioxidative indicators revealed an increase in the sows’ serum FRAP (ferric ion reducing antioxidant power) (p < 0.05) and a decrease of protein carbonyl (p < 0.05) on day 109 of gestation in the RS or FSF group versus the CON group. Overall, inclusion of 5% RS with greater swelling capacity in the gestation diet contributed to enhancing the postprandial satiety, alleviating the stress status, reducing the abnormal behaviors and thus lowering the stillbirth rate of sows.

Influence of the metabolic state during lactation on milk production in modern sows

Selection for prolificacy in sows has resulted in higher metabolic demands during lactation. In addition, modern sows have an increased genetic merit for leanness. Consequently, sow metabolism during lactation has changed, possibly affecting milk production and litter weight gain. The aim of this study was to investigate the effect of lactational feed intake on milk production and relations between mobilization of body tissues (adipose tissue or skeletal muscle) and milk production in modern sows with a different lactational feed intake. A total of 36 primiparous sows were used, which were either full-fed (6.5 kg/day) or restricted-fed (3.25 kg/day) during the last 2 weeks of a 24-day lactation. Restricted-fed sows had a lower milk fat percentage at weaning and a lower litter weight gain and estimated milk fat and protein production in the last week of lactation. Next, several relations between sow body condition (loss) and milk production variables were identified. Sow BW, loin muscle depth and backfat depth at parturition were positively related to milk fat production in the last week of lactation. In addition, milk fat production was related to the backfat depth loss while milk protein production was related to the loin muscle depth loss during lactation. Backfat depth and loin muscle depth at parturition were positively related to lactational backfat depth loss or muscle depth loss, respectively. Together, results suggest that sows which have more available resources during lactation, either from a higher amount of body tissues at parturition or from an increased feed intake during lactation, direct more energy toward milk production to support a higher litter weight gain. In addition, results show that the type of milk nutrients that sows produce (i.e. milk fat or milk protein) is highly related to the type of body tissues that are mobilized during lactation. Interestingly, relations between sow body condition and milk production were all independent of feed level during lactation. Sow management strategies to increase milk production and litter growth in modern sows may focus on improving sow body condition at the start of lactation or increasing feed intake during lactation.

Genetic parameters of sow feed efficiency during lactation and its underlying traits in a Duroc population

As a result of the genetic selection for prolificacy and the improvements in the environment and farms management, litter size has increased in the last few years so that energy requirements of the lactating sow are greater. In addition, selection for feed efficiency of growing pigs is also conducted in maternal lines, and this has led to a decrease in appetite and feed intake that is extended to the lactation period, so the females are not able to obtain the necessary energy and nutrients for milk production and they mobilize their energetic reserves. When this mobilization is excessive, reproductive and health problems occur which ends up in an early sow culling. In this context, it has been suggested to improve feed efficiency at lactation through genetic selection. The aim of this study is to know, in a Duroc population, the genetic determinism of sow feed efficiency during lactation and traits involved in its definition, as well as genetic and environmental associations between them. The studied traits are daily lactation feed intake (dLFI), daily sow weight balance (dSWB), backfat thickness balance (BFTB), daily litter weight gain (dLWG), sow residual feed intake (RFI) and sow restricted residual feed intake (RRFI) during lactation. Data corresponded to 851 parities from 581 Duroc sows. A Bayesian analysis was performed using Gibbs sampling. A four-trait repeatability animal model was implemented including the systematic factors of batch and parity order, the standardized covariates of sow weight (SWf) and litter weight (LWs) at farrowing for all traits and lactation length for BFTB. The posterior mean (posterior SD) of heritabilities were: 0.09 (0.03) for dLFI, 0.37 (0.07) for dSWB, 0.09 (0.03) for BFTB, 0.22 (0.05) for dLWG, 0.04 (0.02) for RFI and null for RRFI. The genetic correlation between dLFI and dSWB was high and positive (0.74 (0.11)) and null between dLFI and BFTB. Genetic correlation was favourable between RFI and dLFI and BFTB (0.71 (0.16) and −0.69 (0.18)), respectively. The other genetic correlations were not statistically different from zero. The phenotypic correlations were low and positive between dLFI and dSWB (0.27 (0.03), dSWB and BFTB (0.25 (0.04)), and between dLFI and dLWG (0.16 (0.03)). Therefore, in the population under study, the improvement of the lactation feed efficiency would be possible either using RFI, which would not have unfavourable correlated effects, or through an index including its component traits.

Effect of increasing dietary energy density during late gestation and lactation on sow performance, piglet vitality, and lifetime growth of offspring.

Genetic selection for hyperprolificacy in sows has resulted in a significant increase in the number of piglets born alive per litter but subsequently, decreased piglet vitality and growth. As a consequence, increasing sows' energy intake during lactation to help increase piglet vitality and growth is increasingly important. The objective of this study was to investigate the effect of increasing dietary energy density for lactating sows on weight and back-fat changes in sows, milk composition, and vitality and growth of progeny. Gestating sows (N = 100; Large White × Landrace) were randomly assigned to one of four energy dense diets at day 108 of gestation until subsequent service; 13.8 (LL), 14.5 (L), 15.2 (H), and 15.9 MJ DE/kg (HH). All diets contained 1.2% total lysine. Blood samples from sows were taken on day 108 of gestation and at weaning (day 26 of lactation) and colostrum (day 0) and milk samples (day 14) were collected during lactation. Sow lactation feed intakes were recorded daily. The number of piglets born per litter (total and live), piglet birth weight (total and live), intrauterine growth restriction (IUGR) traits and muscle tone were recorded in piglets at birth. Piglet tympanic ear temperature (TEMP) was recorded at birth and at 24 h. Pigs were weighed on days 1, 6, 14, 26, 33, 40, 54, 75, and 141 of life. Postweaning (PW) pigs were fed standard cereal-based diets. Pig carcass data were collected at slaughter (day 141). Lactation energy intake was higher for HH sows than for all other treatments (P < 0.01). Colostrum and milk composition and lactation feed intake were not affected by treatment. The number of piglets born per litter (total and live) and piglet birthweight (total and live) was similar between treatments. Piglets from LL sows had more IUGR traits (P < 0.01), while those from HH sows had better muscle tone (P < 0.01) than all other treatments. Piglets from LL sows (P < 0.01) and piglets from H sows (P < 0.01) had a higher 24 h TEMP than piglets from HH sows. H sows weaned a greater number of piglets than L sows (P < 0.05) and HH sows (P < 0.01), while L sows weaned lighter litters than H (P < 0.05) and LL sows (P < 0.05). Pig growth PW was unaffected by treatment. High energy dense diets increased energy intake in sows, without depressing appetite. Feeding an HH diet improved piglet muscle tone at birth, whereas feeding an H diet increased litter size at weaning. Inconsistent results were observed for other traits of piglet vitality and for preweaning litter growth performance.