Lactation Feed Intake Research Articles

Effects of dietary inclusion of Opuntia ficus-indica on the glycemia and productive performance in lactating sows

Sows with increased blood glucose during late gestation may have decreased feed intake in lactation. Supplying dietary fibre to the sow reportedly modulates blood glucose and improves feed intake. The objective of this study was to evaluate the effects of dietary inclusion of cactus (Opuntia ficus-indica) on the regulation of blood glucose and productive performance in lactating sows. Data from 52 hybrid sows were analysed. The sows were divided into two groups, namely a control group (CG), that is, sows fed conventionally; and an experimental group (EG), that is, sows fed commercial feed plus cacti. Blood glucose in late gestation, and feed intake, milk production and milk quality, development of the piglet, energy balance, post-weaning body weight balance and the interval from weaning to oestrus were recorded. Preprandial blood glucose was 55.9 mg per dL in EG and 71.4 in CG. Sows on EG had greater daily feed intake and lower negative energy balance (5.4 kg/day and -2.8 MJ/day) than those on CG (4.5 kg/day and -9.4 MJ/day). Sows fed EG produced more milk (8.6 L/day) than those on CG (8.1 L/day). The quality of milk produced and the weaning weight of piglets were similar for the two groups. Body weight balance after weaning was greater for sows fed EG, 3.5% versus -1.5% in those fed CG. The weaning to oestrus interval was 0.6 days less for sows fed EG than those fed CG. Feeding cactus to lactating sows regulated blood glucose, which improved most of their productive indicators.Keywords: cactus, dietary fibre, energy balance, hypophagia, piglet

Dietary supplementation with different types of fiber in gestation and lactation: effects on sow serum biochemical values and performance.

ObjectiveThree types of dietary fiber were fed to sows during gestation and lactation stages to monitor their physiological and metabolic adaptations during the pre-partum period and to determine how these effects may influence the lactation period and sow performance.MethodsSoon after breeding, 54 sows were selected and were fed with 20% supplementation as fed of wheat bran (WB), soya hulls (SH), or rice hulls (RH) in diets during gestation and lactation. Sows were weighed, backfat thickness was measured ultrasonically and jugular blood samples were collected from all sows. The litter size was equalized to 10, by fostering piglets from sows on the same treatment.ResultsSows gained 22.0, 21.8, and 25.5 kg of net maternal body weight during gestation (for WB, SH, and RH sows, respectively; p = 0.007). There was no treatment effect on the body weight change during lactation (p = 0.158), however RH sows consumed an average of 133.66 kg of feed, WB sows took 121.29 kg and SH sows took 126.77 kg during lactation (p<0.001). The SH litters gained an average of 59.34 kg of weight during lactation, while other litters gained 51.58 and 49.98 kg (for WB and RH litters, respectively; p<0.001). Exception for aspartate aminotransferase and alanine aminotransferase, measured serum biochemical values were broadly in agreement with earlier reports. Despite the use of additional vegetable oil to balance the energy level, RH sows still had lower concentrations of serum triglycerides in late gestation.ConclusionDifferent types of fibrous ingredients in the gestation diet influenced most of the investigated reference values for sows. The values of serum biochemical parameters were generally not affected by fiber type during the lactation stage. The SH supplementation for sows is an effective approach to give heavier litters at birth and weaning and to increase voluntary feed intake in early lactation.

The effect of feeding strategy during rearing in a commercial setting on gilt body condition, lactation performance and culling rate in modern sows nursing large litters

In intensive pig herds, a large proportion of culled sows are first and second parity sows. However, this is economically unfavorable. Gilt body condition is important in relation to gilt performance and different feeding strategies have been suggested to promote the optimal gilt body condition at first service. However, intensive breeding has led to the need for more knowledge on the effects of feeding strategy during rearing in a commercial setting in modern sows nursing large litters ≥ 14 piglets. The objective of this study was therefore to study the effect of feeding strategy during rearing on gilt body condition and performance in the first lactation including, litter size and weight, milk production and composition, lactation feed intake and body mobilization, and culling rate postweaning. A total of 270 primiparous gilts of commercial Danish Landrace x Danish Yorkshire were fed two different feed levels (restrictive/semi ad libitum) during rearing in a group housing system and overall production performance was measured where 39 gilts underwent additional recordings. Results showed that there was a large variation in body condition within each of the feeding treatments. However, semi ad libitum fed gilts were fatter compared to restrictively fed gilts (P < 0.05) at first service. However, there was no effect of feeding strategy during rearing on the overall performance and culling rate postweaning. Results from gilts that underwent additional recordings showed that restrictively fed gilts produced litters with a higher birth weight than semi ad libitum fed gilts (21.2 kg vs. 18.6 kg; SEM 1.05; P ≤ 0.01) and semi ad libitum fed gilts had a higher percentage of milk protein on day 14 (4.8%) and 21 (4.6%) in lactation compared to restrictively fed gilts (4.1 and 4.2%; P < 0.01). In conclusion, increasing feed level during rearing in a commercial setting created a large variation in body condition, but semi ad libitum fed gilts were fatter at first service. This did, however, not affect the overall performance and culling rate of primiparous sows and it is therefore not economically favorable.

Effect of l-carnitine supplementation and sugar beet pulp inclusion in gilt gestation diets on gilt live weight, lactation feed intake, and offspring growth from birth to slaughter1.

This study evaluated the effects of l-carnitine (CAR) and sugar beet pulp (SBP) inclusion in gilt gestation diets on gilt live weight, cortisol concentration, lactation feed intake, and lifetime growth of progeny. Eighty-four pregnant gilts (Large White × Landrace) were randomly assigned to a treatment at day 38 of gestation until parturition; Control (0% SBP, 0 g CAR), CAR (0.125 g/d CAR), SBP (40% SBP), and SBP plus CAR (40% SBP, 0.125 g/d CAR). Gilts were weighed and back-fat depth was recorded on day 38, day 90, and day 108 of gestation and at weaning. Gilt saliva samples were collected pre-farrowing and fecal consistency was scored from entry to the farrowing room until day 5 post-partum. The number of piglets born (total, live, and stillborn) and individual birth weight was recorded. Piglet blood glucose concentration was measured 24 h post-partum and pigs were weighed on day 1, day 6, day 14, day 26, day 76, day 110, and day 147 of life. Carcass data were collected at slaughter. There was no interaction between CAR and SBP for any variable measured. The SBP-fed gilts were heavier on day 90 and day 108 of gestation (P < 0.05) and lost more weight during lactation (P < 0.05) than control gilts. They also had a greater fecal consistency score (P < 0.01). Total farrowing duration, piglet birth interval, and lactation feed intakes were similar between treatments (P > 0.05). The number of piglets born (total, live, and stillborn) and piglet birth weight was likewise similar between treatments (P > 0.05). Piglets from CAR-fed gilts had lower blood glucose concentrations (P < 0.01), while piglets from SBP-fed gilts had greater blood glucose concentrations (P < 0.01). Piglets from CAR gilts had a lower average daily gain between day 1 and day 6 (P < 0.05) and day 14 and day 26 post-partum (P < 0.05) compared to piglets from control gilts. However, CAR gilts weaned a greater number of pigs (P = 0.07). Live weight and carcass weight at slaughter were heavier for pigs from CAR gilts (P < 0.05) and from SBP gilts (P < 0.05). Pigs from CAR gilts (P < 0.01) and SBP gilts (P < 0.05) had increased carcass muscle depth. In conclusion, no benefit was found from the combined feeding of CAR and SBP. Fed separately, CAR increased the live weight, carcass weight, and muscle depth of progeny at slaughter. Feeding a high SBP diet increased fecal consistency in gilts pre-farrowing and increased live weight and carcass muscle depth of progeny.

PSII-18 Greater feed amounts during late gestation do not improve piglets birth weight: a dose-response study performed in gilts

Abstract In breeding farms, pork producers commonly use “bump feeding” as a feeding strategy. This technique consists of increasing daily feed amount on late gestation to improve piglets birth weight. A dose-response arrangement with 4 treatments (1.8, 2.3, 2.8, and 3.3 kg/d) was used to evaluate the effects on female reproductive performance and piglet birth weight. A total of 977 gilts were fed based on a corn-soybean meal diet from day 90 of gestation until farrowing. Gilts were weighed on days 90 and 112 of gestation and at weaning. Born alive and stillborn piglets were weighed within 12 h of birth. Colostrum yield and lactation feed intake were measured in a randomly selected sub-sample of 245 gilts. As expected, body weight gains were different at day 112 (P &lt; 0.001) with the highest values observed in 3.3 kg/d treatment. As the feed amount increased during late gestation, greater were the body losses between d 112 and weaning (P &lt; 0.001). Statistical tendencies for a quadratic effect of feeding level were observed for piglets born alive (P = 0.079), average birth weight of piglets (P = 0.083), and litter weight (P = 0.059). However, there were no differences among treatments on total born and mummified fetuses (P &gt; 0.05). Gilts fed with lower feed amounts during late gestation had reduced stillborn percentages compared to those gilts fed with greater amounts. Colostrum yield and voluntary feed intake decreased linearly (P &lt; 0.05) as the feed amount performed during late gestation increased. In conclusion, increasing the feed intake from day 90 of gestation until farrowing increased gilts body weight and stillborn rate, but reduced the colostrum yield and the lactation feed intake. In addition, there were no effects of the feeding level in late gestation on piglets birth weight.

27 Defining a robust sow: swine nutrition perspective on reproduction and lactation

Abstract Improvements in modern sow prolificacy have markedly increased the number of pigs weaned, thus the ability of sows to provide nutrients to support fetal growth and milk production has been enhanced. The goals of the gestation nutrition program consist of meeting the nutrient requirements for maintenance and growth and for adequate conceptus development, while managing body condition. Early gestation represents the best opportunity for replenishing body reserves, whereas in late gestation, both estimated protein deposition and energy requirement are exponentially increased and directed towards fetal growth and mammary development. Increased feed intake after breeding has been presumed to be detrimental to embryo survival; however, data with modern line sows demonstrates to feed thin sows to recover body condition as quickly as possible while avoiding feed deprivation immediately after breeding. Importance of body condition scoring remains unchanged: feed thin sows to bring back to adequate body condition and prevent over-conditioned sows at farrowing. A recent meta-analysis showed increasing late gestation feed intake seems to modestly improve piglet birth weight by 28 g per piglet in gilts and sows. Also, recent findings in gestating sows suggest modern genotypes have improved feed efficiency and propensity for growth. Therefore, increasing energy intake during late gestation has a modest effect on piglet birth weight and a negative effect on stillborn rate. Historically, lactation catabolism impacted subsequent reproductive performance of sows, particularly in first-parity. However, contemporary sows appear to be increasingly resistant to the negative effects of lactational catabolism. Even so, continued emphasis on maximizing lactation feed intake is critical to support milk production and prevent excessive lean tissue mobilization. Research data suggests that ad libitum feeding and offering lactation diets during the wean-to-estrus interval is not needed. Modern genetic sow lines appear to be more robust from a nutritional perspective than in the past.

Effects of supplementing processed straw during late gestation on sow physiology, lactation feed intake, and offspring body weight and carcass quality1.

This study investigated the effects of supplementing late gestation sow diets with processed or unprocessed oat or wheat straw on physiology, early lactation feed intake, and offspring performance. One hundred fifty gestating sows were randomly assigned to 1 of 5 dietary treatments (30 sows per diet) from day 86 of gestation until farrowing. Treatments, arranged as a 2 × 2 factorial plus a control, were a standard gestation diet (control) or control supplemented with 10% wheat or oat straw, processed or unprocessed. Sows were fed a standard lactation diet postfarrowing. The processed straws were produced by high-pressure compaction at 80 °C. On day 101 of gestation (day 15 of the trial), blood samples were collected from a subset of sows (n = 8 per treatment) through ear vein catheters and analyzed for insulin, insulin-like growth factor 1 (IGF-1), prolactin, glucose, and urea concentrations. Fecal samples were collected on days 103 to 104 of gestation to determine nutrient digestibility, and feeding motivation was investigated on day 104. Litter characteristics and sow feed intake were recorded for 7 d postfarrowing. Three piglets per litter were selected at weaning, fed standard diets, and followed to market. Treatment had no effect on feeding motivation, piglet characteristics at birth, estimated milk production, and offspring BW at market or carcass quality. Processed straw improved DM digestibility and energy content and the effect was greater with oat straw (straw × processing effect, P < 0.05). Pre- and postprandial glucose concentrations tended to decrease (P < 0.10) with processing of wheat, but not oat straw, and this effect was more apparent in the preprandial samples. Preprandial prolactin concentration increased with oat but decreased with wheat straw, whereas postprandial IGF-1 and prolactin concentration increased with processing of wheat, but not oat straw (straw × processing, P < 0.05). Sow lactation feed intake improved (P < 0.05) with oat straw supplementation relative to wheat straw. Piglet weaning weight increased (P < 0.05) with oat straw supplementation and processing improved (P < 0.05) nursery exit BW. However, straw supplementation, regardless of processing, had no effect on offspring BW at market or carcass quality. Overall, oat straw supplementation had a greater impact on sow physiology and provided benefits for sows in late gestation, and there was some indication that further benefits could be obtained through mild processing.

Effects of Bacillus subtilis C-3102 on sow and progeny performance, fecal consistency, and fecal microbes during gestation, lactation, and nursery periods1,2

This study evaluated the effects of providing a dietary probiotic, Bacillus subtilis C-3102, to sows during gestation and lactation and to progeny after weaning on performance, fecal consistency, and fecal microbes. For the sow portion of the study, 29 sows and litters were used from day 30 of gestation until weaning. Sow treatments consisted of control diet or probiotic diet with B. subtilis C-3102 at 500,000 cfu/g of gestation feed and 1,000,000 cfu/g of lactation feed. For the nursery portion of the study, 358 weaned pigs, progeny of sows on study, were used in a 42-d nursery study. Nursery treatments consisted of control diet or probiotic diet with B. subtilis C-3102 and prebiotics at 500,000 cfu/g of nursery feed. Treatments were arranged in a split-plot design with sow treatment (control or probiotic diet) as main plot and nursery treatment (control or probiotic diet) as subplot. Performance, fecal consistency by fecal score method, and fecal microbes by isolation and enumeration method were assessed. In lactation, probiotic-fed sows tended (P = 0.057) to have increased feed intake, but it did not improve (P > 0.05) sow or litter performance in lactation. In the nursery, there were no (P > 0.10) interactions or main effects of sow or nursery treatments on overall growth performance. However, pigs born from control-fed sows had greater (P < 0.05) average daily gain, average daily feed intake, and body weight in late nursery than pigs born from probiotic-fed sows. Fecal score evaluation of nursing and nursery pigs indicated no influence (P > 0.05) of sow or nursery treatments on fecal consistency. Fecal microbial analysis revealed a modest modification in fecal microbial population by increasing (P < 0.05) the number of total Bacillus sp. in probiotic-fed sows and nursery pigs. Nursing piglets born from probiotic-fed sows carried over (P < 0.05) this modification in fecal microbial population preweaning. In conclusion, providing a probiotic based on B. subtilis C-3102 to sows during gestation and lactation and to progeny after weaning did not elicit noteworthy improvements in performance or fecal consistency, but there was a benefit on sow lactation feed intake. Fecal microbial analysis indicated a maternal-progeny intestinal microbiota relationship with pigs born from probiotic-fed sows displaying similar fecal microbial population as sows. However, pigs born from probiotic-fed sows demonstrated reduced growth rate and feed consumption in late nursery.

Impact of feed intake during late gestation on piglet birth weight and reproductive performance: a dose-response study performed in gilts

The effects of increasing feed intake (1.8, 2.3, 2.8, and 3.3 kg/d) during late gestation of gilts on piglet birth weight and female reproductive performance were evaluated. A total of 977 gilts were fed a diet based on corn-soybean meal (3.29 Mcal ME per kg and 0.64% standardized ileal digestible lysine) from day 90 of gestation until farrowing. Gilts were weighed on days 90 and 112 of gestation, at farrowing and weaning. Born alive and stillborn piglets were weighed within 12 h of birth. Colostrum yield (CY), lactation feed intake, and litter growth rate were measured in a randomly selected subsample of 245 gilts. The data were analyzed using generalized linear mixed models. As expected, gains in body weight (BW) were different at day 112 (P < 0.001) with the greatest values observed in the 3.3 kg/d treatment. As feed intake increased during late gestation, BW, body condition score (BCS), backfat (BF), and Caliper unit also increased between day 112 and weaning (P < 0.001). No differences were found among treatments in total number of piglets born, mummified fetuses, sum of born alive and stillborn piglets, and within-litter birth weight CV (P > 0.05). Tendencies for quadratic effect of feed intake were observed for born alive piglets (P = 0.079), average birth weight of piglets (P = 0.083), and litter weight (P = 0.059). Gilts with lower feed intake during late gestation had reduced percentages of stillborn piglets than gilts with greater feed intakes. The CY decreased linearly (P < 0.05) as the feed intake was increased. No differences among treatments were found at weaning in individual piglet weight and litter weight, as well as in percentage of weaned piglets (P > 0.05). Lactation feed intake decreased as gestation feeding level increased (P < 0.05). No differences in the subsequent cycle were observed among treatments for farrowing rate, retention rate up to the next farrowing, number of total piglets born, born alive, stillborn piglets, and mummified fetuses (P > 0.05). In conclusion, increased feed intake from day 90 of gestation until farrowing resulted in increased maternal BW gain and stillborn rate, but reduced CY and lactation feed intake. A slight increase in birth weight was observed for the 2.3 kg/d treatment. Furthermore, litter growth and subsequent female reproductive performance were not affected by feed intake during late gestation.

An association analysis of sow parity, live-weight and back-fat depth as indicators of sow productivity

Understanding how critical sow live-weight and back-fat depth during gestation are in ensuring optimum sow productivity is important. The objective of this study was to quantify the association between sow parity, live-weight and back-fat depth during gestation with subsequent sow reproductive performance. Records of 1058 sows and 13 827 piglets from 10 trials on two research farms between the years 2005 and 2015 were analysed. Sows ranged from parity 1 to 6 with the number of sows per parity distributed as follows: 232, 277, 180, 131, 132 and 106, respectively. Variables that were analysed included total born (TB), born alive (BA), piglet birth weight (BtWT), pre-weaning mortality (PWM), piglet wean weight (WnWT), number of piglets weaned (Wn), wean to service interval (WSI), piglets born alive in subsequent farrowing and sow lactation feed intake. Calculated variables included the within-litter CV in birth weight (LtV), pre-weaning growth rate per litter (PWG), total litter gain (TLG), lactation efficiency and litter size reared after cross-fostering. Data were analysed using linear mixed models accounting for covariance among records. Third and fourth parity sows had more (P<0.05) TB, BA and heavier BtWT compared with gilts and parity 6 sow contemporaries. Parities 2 and 3 sows weaned more (P<0.05) piglets than older sows. These piglets had heavier (P<0.05) birth weights than those from gilt litters. LtV and PWM were greater (P<0.01) in litters born to parity 5 sows than those born to younger sows. Sow live-weight and back-fat depth at service, days 25 and 50 of gestation were not associated with TB, BA, BtWT, LtV, PWG, WnWT or lactation efficiency (P>0.05). Heavier sow live-weight throughout gestation was associated with an increase in PWM (P<0.01) and reduced Wn and lactation feed intake (P<0.05). Deeper back-fat in late gestation was associated with fewer (P<0.05) BA but heavier (P<0.05) BtWT, whereas deeper back-fat depth throughout gestation was associated with reduced (P<0.01) lactation feed intake. Sow back-fat depth was not associated with LtV, PWG, TLG, WSI or piglets born alive in subsequent farrowing (P>0.05). In conclusion, this study showed that sow parity, live-weight and back-fat depth can be used as indicators of reproductive performance. In addition, this study also provides validation for future development of a benchmarking tool to monitor and improve the productivity of modern sow herd.

Two different feeding levels during late gestation in gilts and sows under commercial conditions: impact on piglet birth weight and female reproductive performance.

The increase in the litter size in past decades has caused reduction in the individual piglet birth weight. Therefore, nutritional strategies employed in the last third of gestation in order to improve the piglet birth weight have been studied. This study aimed to evaluate the effects of 2 different feeding levels (1.8 and 2.2 kg/d) in the last third of gestation on the piglet birth weight and the female reproductive performance. A total of 407 females were fed on a diet based on corn-soybean meal (3.25 Mcal ME per kg and 0.65% standardized ileal digestible lysine) from day 90 of gestation until farrowing. The females were weighed on day 90 and day 112 of gestation, and at weaning. Born alive and stillborn piglets were weighed within 12 h of birth. The lactation feed intake and the litter growth rate were measured in a randomly selected subsample of 53 sows from each treatment. The data were analyzed using the generalized linear mixed models, considering the females as the experimental unit. Parity, treatment, and their interaction were analyzed for all responses. The females fed on 2.2 kg/d of diet from day 90 to day 112 exhibited greater body weight gain compared to the females fed on 1.8 kg/d (P < 0.001). No evidence of the effects of feeding levels on the individual piglet birth weight and on the within-litter CV were observed, for both gilts and sows (P ≥ 0.90). Similarly, when the classes of the total born piglets were considered in the analysis (<15 and ≥15 for gilts; <16 and ≥16 for sows), no positive effects of increasing the feeding level were observed on the individual piglet birth weight and the within-litter CV (P ≥ 0.47). Also, no differences in the stillborn rate, mummified-fetus rate, and percentage of piglets weighing less than 1,000 g at birth were observed between the treatments (P ≥ 0.28). The females fed on 1.8 kg/d of diet exhibited greater feed intake during lactation, compared to the females fed on 2.2 kg/d (P < 0.05). Weaning weight, weaning-to-estrus interval, subsequent litter size, and culling rate were not affected by the dietary levels (P ≥ 0.23). In conclusion, increasing the feed intake from day 90 of gestation until farrowing increased the body weight gain in sow, demonstrated no effect on the piglet birth weight, and reduced the lactation feed intake. Furthermore, there was no evidence of the effects of the treatments on the litter growth rate or on the subsequent female reproductive performance.

Effect of canola meal inclusion as a major protein source in gestation and lactation sow diets with or without enzymes on reproductive performance, milk composition, fecal bacterial profile and nutrient digestibility

The aim was to determine the effects of high canola meal (CM) inclusion in gestation and lactation diets on reproductive performance, milk composition, fecal bacterial profile and nutrient and energy digestibility of sows. Forty-five sows were randomly assigned to 1 of 3 dietary treatments consisting of a corn-soybean meal control diet, control diet containing 300 g/kg solvent-extracted CM with or without multi-enzyme complex (MC). Sows were individually housed and offered the experimental diets from day 60 of gestation until weaning on day 21. Sows were weighed and backfat thickness measured on days 60 and 111 of gestation, and on days 0 and 21 post-farrowing. Litters were weighed on days 0 and 21. Weaning to estrus interval in sows was recorded. Blood and milk samples were collected 2 h post-feeding from sows on days 0 and 21 to determine the plasma urea nitrogen (PUN) content and milk composition. Fecal samples were collected from sows during lactation to determine energy and nutrient digestibility, and during gestation and lactation to determine the fecal bacterial profile. There were no dietary effects on lactation feed intake, sow backfat loss, weaning to estrus interval and milk fat, protein and lactose composition, and suckling piglet performance except for sow body weight (BW) loss during lactation, wherein sows fed CM-containing diets with MC had lower (P < 0.05) BW loss than those fed the control diet. Sows fed diets containing CM (with and without MC) had lower (P < 0.05) PUN values compared with those fed the control diet on day 21 post-farrowing. Apparent total tract digestibility (ATTD) of energy and nutrients showed no dietary effect except for ATTD of phosphorus (P), wherein sows fed CM-containing diets with MC showed higher (P < 0.05) P digestibility compared to those fed CM-containing diets without MC. Sows fed CM-containing diets with or without MC had greater (P < 0.05) abundances of Lactobacillus and Enterococcus and lower (P < 0.05) abundances of Firmicutes when compared to those fed the control diet on day 90 of gestation. In conclusion, inclusion of up to 300 g/kg CM in gestation and lactation diet can support satisfactory sow and suckling piglet performance without affecting energy and nutrient digestibility, along with an increase in the abundance of gut lactic acid bacteria in sows. Moreover, enzyme supplementation reduced the sow BW loss and improved P digestibility in CM diets.

Impact of diet deprivation and subsequent overallowance during gestation on lactation performance of primiparous sows.

The impact of diet deprivation followed by overallowance during gestation on metabolic status of pregnant gilts and their lactation performance was determined. Gilts were fed a standard diet until day 27 of gestation and were subsequently reared under a control (CTL; n = 28) or an experimental (treatment, TRT; n = 26) dietary regimen. The experimental regimen provided 70% (restriction diet, RES) and 115% (overallowance diet, OVER) of the protein and NE contents provided by the CTL diet. The RES diet was given from days 28 to 74 of gestation followed by the OVER diet from day 75 until farrowing. Blood samples were obtained from all gilts on days 28, 75, and 110 of gestation, and on days 3 and 20 of lactation to measure concentrations of IGF-1, urea, FFA, and glucose. Milk samples were collected from 12 sows per treatment on day 19 of lactation and sow feed intake was recorded daily throughout lactation. Piglets were weighed at 24 h (after standardization of litter size), and on days 7, 14, and 21 (weaning). The TRT gilts gained less BW than CTL gilts (17.3 vs. 31.7 kg; P < 0.01) from days 28 to 75 of gestation and more BW (29.5 vs. 21.9 kg; P < 0.01) from days 75 to 110, but their overall gain from mating to day 110 was lower (61.4 vs. 67.2 kg; P < 0.05). Metabolic status during gestation was affected, with TRT gilts having less IGF-1 and urea, and more FFA than CTL gilts on day 75 (P < 0.01), and more urea on day 110 (P < 0.01). Growth rate of suckling piglets, sow lactation feed intake, and standard milk composition in late lactation (DM, fat, protein, lactose) were not affected by treatment (P > 0.10). In conclusion, diet deprivation of gilts as of day 28 of gestation followed by overfeeding from day 75 of gestation until farrowing did not improve lactation performance. It is likely that the compensatory growth that took place in late gestation was not adequate to illicit beneficial effects.

Effect of pad-fan cooling and dietary organic acid supplementation during late gestation and lactation on reproductive performance and antioxidant status of multiparous sows in hot weather.

A 2 × 2 factorial arrangement (rearing room with or without pad-fan cooling × diet with or without 2.5kg/t organic acid) was used to evaluate the effect of pad-fan cooling and dietary organic acid supplementation during perinatal period on reproductive performance and antioxidant status of sows in hot weather. This study was conducted in a subtropical city in Guangdong Province in South China between August and October, 2015. At day 85 of gestation, a total of 112 sows were randomly assigned to the four treatments with 28 sows per treatment, and maintained until day 21 of lactation, and the feeding trial lasted for 51days. During the experimental period, room temperature and humidity were recorded hourly. The lactation feed intake of sows (P = 0.109) and stillbirths (P< 0.05) increased when the sows were reared in the room with the pad-fan cooling against the room without pad-fan cooling. The number of weak newborns per litter and the malondialdehyde content in days 14 and 21 milk decreased (P< 0.05), while the lactation feed intake of sows, weaned litter weights, and individual pig weights increased when the sows were fed the organic acid (P< 0.05). In conclusion, pad-fan cooling in rearing room improved the lactation feed intake of sows, and dietary organic acid supplementation improved reproductive performance and milk antioxidant status of sows. Pad-fan cooling is recommended in farrowing room, but not in gestating room.

Effects of soluble fiber inclusion in gestation diets with varying fermentation characteristics on lactational feed intake of sows over two successive parities

The effects of soluble fiber inclusion in gestation diets with varying fermentation characteristics (fermentation kinetics and short-chain fatty acids (SCFA)-profile) on lactational feed intake of sows and their piglet growth over two parities were investigated using an in vitro–in vivo methodology. After breeding, 90 multiparous Landrace sows were randomized to one of three experimental diets: the control (CON) diet, konjac flour (KF) diet or sugar beet pulp (SBP) diet. All diets had similar levels of net energy, CP, insoluble fiber and NDF, but KF and SBP diets had higher soluble fiber levels than the CON diet. During gestation, the sows were restrictively fed with three different diets, but during lactation, all the sows were similarly fed ad libitum. The three gestation diets were enzymatically hydrolyzed using pepsin and pancreatin, and enzymolyzed residues were used in in vitro fermentation. Gas and SCFA production were monitored during fermentation. After fermentation, enzymolyzed residues of KF or SBP diets resulted in higher final asymptotic gas volume than those of the CON diet. The enzymolyzed residues of KF diet were mainly part of rapidly fermented fractions, whereas those of SBP diet were mainly part of slowly fermented fractions. In addition, the acetic acid, butyric acid and total SCFA concentrations of enzymolyzed residues of KF diet were higher (P<0.01) than the control and SBP diets. In the in vivo studies, on day 90 of gestation, the KF diet sows had higher plasma SCFA concentration (P<0.05) at 4 h after feeding than the CON diet sows. Furthermore, the KF diet sows had lower plasma free fatty acid (FFA) concentration (P<0.01) at 4 h after feeding, and a lower value of homeostasis model assessment (HOMA)-insulin resistance (P<0.05), but a higher value of HOMA-insulin sensitivity (P<0.01). The KF diet sows also consumed more feed during lactation (P<0.01) and weaned significantly heavier pigs (P<0.01) than the CON diet sows. The overall results showed that the high fermentation capacity KF diet contributed to an increased lactational feed intake and improved performance of piglets in the second reproductive cycle.

Understanding the drivers of improved pig weaning weight by investigation of colostrum intake, sow lactation feed intake, or lactation diet specification.

Modern sows have low feed intake (FI) during lactation. The main aim of this study was to understand interactions between and separate effects of FI and nutrient density on litter weaning weight (WW). Key drivers of colostrum intake (CIn), piglet survival, WW, and colostrum yield (CY) were also investigated. Sows ( = 82) were offered a High (15.8 MJ/kg DE; 1.3% total lysine) or Normal (15.2 MJ/kg DE; 1.28% total lysine) specification lactation diet at either a High (feed allowance increased by 0.5 kg/d after farrowing until intake reached 10 kg/d) or Low (feed allowance was increased by 0.3 kg/d after farrowing until intake reached 7.5 kg/d) feeding level (2 × 2 factorial design). A subset of sows ( = 18) were observed during farrowing to collect data on factors affecting CIn. No interactions were found between diet specification and feeding level. Sows on the Low feeding level lost 10.6 kg more BW during lactation than those on the High feeding level ( < 0.001). Sows offered the High specification diet lost 6.4 kg more BW than those on the Normal specification diet ( = 0.018). Diet specification had no effect on ADFI. Between birth and weaning, litters of sows offered the High feeding level grew 326 g/d faster ( < 0.001) and were heavier at 28 d (114 kg; < 0.001) compared with those of sows offered the Low feeding level (104 kg). Although litters from sows offered the High specification diet had WW similar to that of litters from sows offered the Normal specification diets, their ADG was 190 g/d greater ( = 0.018) between birth and weaning. A regression analysis was completed using data from 192 sows and indicated that FI and lysine intake throughout lactation and DE and lysine intake from 14 to 28 d of lactation were the main drivers of litter WW. Lactation efficiency was 0.65 from 0 to 7 d and decreased to 0.42 from 21 to 28 d. Variation in CIn was mainly explained by 24-h weight, birth weight, and the duration of farrowing. Colostrum yield was significantly correlated ( = 0.004; pseudo = 54.5%) with litter birth weight. Piglet WW was positively correlated with 3-wk weight ( < 0.001) but negatively correlated with sow parity ( = 0.035), number born alive ( = 0.045), and being female ( < 0001). Out of 45 variables, preweaning piglet survival was positively correlated ( = 0.008) with only 24- to 48-h weight gain. In conclusion, lactation FI and DE and lysine intake in the second half of lactation were the main drivers of litter WW.

Effect of rapeseed meal supplementation to gestation diet on reproductive performance, blood profiles and milk composition of sows.

ObjectiveThis experiment evaluated the effect of dietary supplementation levels of rapeseed meal (RSM) in gestation diets on reproductive performance, blood profiles, milk composition of sows, and growth of their progeny.MethodsA total of 55 mixed-parity sows (Yorkshire×Landrace; average parity = 3.82) with an initial body weight (BW) of 193.0 kg were used in this experiment. Sows were allotted to one of 5 treatments at breeding based on BW and backfat thickness in a completely randomized design. Treatments consisted of dietary RSM supplementation levels (0%, 3%, 6%, 9%, and 12%) in gestation diets. During lactation all sows were fed a common lactation diet with no RSM supplementation.ResultsBody weight, backfat thickness, litter size, lactation feed intake, and milk composition of sows, and growth of their progeny were not different among dietary treatments. In blood profiles, a quadratic increase (Quadratic, p<0.05) in serum triiodothyronine (T3) concentration and a linear increase (Linear, p<0.01) in serum thyroxine (T4) concentration were observed at d 110 of gestation as dietary RSM supplementation levels increased. However, serum T3 and T4 concentrations in lactating sows and their piglets were not affected by RSM supplementation of gestation diets. Concentrations of serum total cholesterol and low density lipoprotein cholesterol in sows were not influenced by dietary treatments, whereas serum glucose level in sows decreased linearly at d 110 of gestation (Linear, p<0.05) by increasing dietary RSM supplementation in gestation diets.ConclusionThe RSM could be supplemented to gestation diets up to 12% with no detrimental effects on reproductive performance and growth of their progeny. However, increasing supplementation levels of RSM in gestation diets may increase serum T3 and T4 concentrations and decrease serum glucose concentration of sows in late gestation.

Effect of increasing dietary canola meal inclusion on lactation performance, milk composition, and nutrient digestibility of lactating sows.

The aim was to determine the effects of increasing dietary canola meal in substitution for soybean meal in lactation sow diets. Forty-five sows with an average parity of 1.8 (SD = 0.83) were randomly assigned to 1 of 3 dietary treatments ( = 15) consisting of a corn-based control diet and 2 diets with 15% and 30% canola meal formulated by replacing soybean meal with canola meal. Diets were formulated to be similar in standardized ileal digestible AA content and NE value and to meet or exceed nutrient recommendations for lactating sows. Sows were moved to farrowing on d 111 of gestation and fed the experimental diets until weaning on d 21. Sows were fed 3.0 kg/d from d 111 of gestation until parturition. After farrowing, feed was gradually increased through d 6 after which the diets were offered on an ad libitum basis until weaning. Sows were weighed and backfat thickness measured on d 111 of gestation and also on d 0, 7, and 21 postfarrowing. Litters were weighed on d 0, 7, and 21. Weaning to estrus interval in sows was also recorded. Blood and milk samples were collected 2 h postfeeding from sows on d 0, 7, and 21 and analyzed for plasma urea nitrogen (PUN) and milk composition. Fecal samples were collected on d 10, 11, and 12 postfarrowing to determine energy and nutrient digestibility. There were no dietary effects on lactation feed intake, sow BW and backfat change, weaning to estrus interval, and milk fat, protein, lactose, and urea composition. Also, there were no dietary effects on piglet ADG ( 0.10). Sows fed diets containing 15% and 30% canola meal had lower (linear, < 0.05) PUN values compared with those fed the control diet on d 0, 7, and 21 postfarrowing. Apparent total tract digestibility of DM, GE, CP, and P were reduced linearly ( < 0.05) with increasing canola meal inclusion. In conclusion, up to 30% canola meal in lactation diet can support satisfactory sow and suckling piglet performance.

Analysis of lactation feed intakes for sows with extended lactation lengths.

The objectives of this research were to quantify and model daily feed intakes to 28 d of lactation in modern sows. A total of 4,512 daily feed intake (DFI) records were collected for 156 Hypor sows from February 2015 to March 2016. The mean lactation length was 27.9 ± 2.0 d. The data included 9 parity 1, 33 parity 2 and 114 parity 3+ sows. Data were collected using a computerized feeding system (Gestal Solo, JYGA Technologies, Quebec, Canada). The feeding system was used to set an upper limit to DFI for the first 7 d of lactation. Overall, the least-squares means of a model including the random effect of sow indicated that DFI's continued to slowly increase to 28 d of lactation. The DFI data were fitted to Generalized Michaelis-Menten (GMM) and polynomial functions of day of lactation (t). The GMM function [DFIi,t (kg/d) = DFI0 + (DFIA − DFI0)(t/K)C/[1 + (t/K)C]] was fitted with 2 random effects for DFI (dfiAi) and intercept (dfi0i) using the NLMIXED procedure in SAS®. The polynomial function DFIi,t (kg/d) = [B0 + B1 t + B2 t2 + B3 t3 + B4 t4] was fitted with three random effects for B0, B1, and B2 using the MIXED procedure in SAS®. Fixed effects models of the two functions had similar Akaike's Information Criteria (AIC) values and mean predicted DFI's. The polynomial function with 3 random effects provided a better fit to the data based on R2 30 (0.81 versus 0.79), AIC (14,709 versus 15,158) and RSD (1.204 versus 1.321) values than the GMM function with two random effects. The random effect for B2 in the polynomial function allowed for the fitting of the function to lactation records that had decreased DFI after 15 d of lactation. The random effects for the polynomial function were used to sort the lactation records into three groups based on the derivative of the function at 21 d of lactation. Lactation records of the three groups had similar DFI the first two weeks of lactation (P > 0.40). The three groups of sows had substantially different DFI's after 18 d of lactation (P < 0.028). The differences in both actual and predicted DFI's between the three groups increased with each day of lactation to day 28 (P < 0.001). Mixed model polynomial functions can be used to identify sows with different patterns of DFI after 15 d of lactation.

Providing the plant extract silymarin to lactating sows: effects on litter performance and oxidative stress in sows

Silymarin is an extract from the plant milk thistle that was shown to have antioxidant and hyperprolactinemic properties. Taking into account the essential role of prolactin for lactating sows and the systemic oxidative stress occurring during lactation, it is of interest to investigate the potential beneficial effects of silymarin on lactating sows. A study was therefore carried out to determine the effects of providing either 1 or 8 g/day of the plant extract silymarin to lactating sows. Sows in first, second or third parity were fed conventional diets during gestation and, at farrowing, were assigned as controls (CTL, n=33), or were fed 1 g/day (SYL1, n=33) or 8 g/day (SYL8, n=33) of silymarin. The silymarin was provided in two equal amounts per day, and was fed throughout a 20-day lactation. The performance of sows and their litters was assessed and circulating concentrations of prolactin (days 7 and 18), urea (days 7 and 18) and oxidative status, via protein carbonyls and superoxide dismutase activity (day 18), were measured in sows. Milk samples were obtained on day 18 to measure standard composition. There was no effect of silymarin (P>0.10) on circulating prolactin or urea, or on oxidative damage to proteins or antioxidant potential in sows. Lactation feed intake, backfat and BW of sows were unaffected by treatment (P>0.10) as was the case for milk composition and piglet growth (P>0.10). Results demonstrate that providing up to 8 g/day of the plant extract silymarin to lactating sows had no beneficial effects in terms of circulating prolactin concentrations or oxidative status of sows, or in terms of performances of sows and their litters.