Effect of dietary supplementation of oregano essential oils to sows on colostrum and milk composition, growth pattern and immune status of suckling pigs

This study evaluated the effects of supplementing sow diets with oregano essential oils (OEO) during gestation and lactation on sow colostrum and milk composition and on the growth pattern and immune status of suckling pigs. A total of 70 second-parity sows were randomly assigned to 1 of 2 gestation dietary treatments within 24 h after service: control (CON) or CON + 250 mg/kg of OEO (OREG). In lactation, sows were again assigned to either the CON or OREG dietary treatment. Thus, the lactation treatments were CON-CON, CON-OREG, OREG-CON, and OREG-OREG. Colostrum and blood samples were collected from 6 sows per lactation dietary treatment. Thymus lymphocyte (T lymphocyte) subpopulations (γδ, cluster of differentiation 8, and 32 cluster of differentiation 4) were enumerated in blood and mammary secretions along with IGF-1, IgG, and IgA concentrations. Piglet growth rate were determined from 18, 17, 17, and 18 litters from the CON-CON, CON-OREG, OREG-CON, and OREG-OREG lactation dietary treatments, respectively. Growth rates were determined in 630 piglets, and piglets were individually identified and weighed on 1, 5, 9, 12, 16, and 19 d of age. Oregano essential oil supplementation during gestation or lactation had no effect (P > 0.05) on GE, CP, GE:CP, GE:fat, and IGF-1 in sow milk. Reductions of the fat percentage in milk on d 7 (P < 0.05) and d 14 (P = 0.07) were found in sows supplemented with OEO during lactation compared with those in the CON treatment. Milk from sows supplemented with OEO during lactation had the greatest number of T lymphocytes compared with those in the lactation CON treatment on d 14 of lactation (P < 0.01). The number of T lymphocytes in milk was greater for sows in the CON-OREG treatment compared with those other treatments on d 14 of lactation (P < 0.05). Energy intake was greater on d 1 to 5 in piglets from sows fed OEO during gestation than those from sows in the CON treatment (P < 0.05). A trend (P = 0.10) for greater milk intake was observed in piglets from sows supplemented with OEO during gestation compared with those from sows in the CON treatment. Similarly, a tendency for an increase in ADG on d 1 to 5 was found in piglets from sows supplemented with OEO during gestation compared with those from sows in the CON treatment (P = 0.10). Insulin-like growth factor-1 at birth and on d 7 and 14 of lactation did not differ among piglets from sows assigned to the different dietary treatments. Oregano essential oil supplementation of sow diets did not affect (P > 0.05) immunoglobulin concentrations in piglets after suckling. Supplementing sow diets with OEO during gestation or lactation did not affect (P > 0.05) the T lymphocytes, percentage of T-lymphocyte subpopulations, and natural killer cell activity of piglets during lactation. Supplementing sow diets with 250 mg/kg of OEO during gestation and lactation did not affect the growth potential of and immune responses in suckling piglets.     

Effect of roasted or raw peanut kernels on lactation performance and milk composition of swine

A lactation trial involving 105 sows was conducted to determine the effect of 12% roasted or raw, ground, whole, shelled peanuts on sow weight change during lactation, feed intake, piglet and litter weight gain, milk composition, and days to return to postweaning estrus. The trial was conducted using three sow groups during two farrowing seasons, summer (July to September) and winter (December to February). Diets were based on corn plus soybean meal. Diets contained either 5% animal fat or equivalent added fat from 12% roasted or raw, ground, shelled peanuts. The replacement of animal fat by roasted or raw peanuts had no effect (P greater than .20) on sow weight change, average daily feed intake during lactation or days to estrus postweaning, or on piglet weight gain or survival. Milk composition (percentage fat and protein) was not altered (P greater than .20) by source of fat in the summer; however, in the winter, sows fed roasted peanuts had higher (P less than .05) milk fat and protein percentage at 3 d postfarrowing than other treatment groups. At d 7, sows fed 12% roasted or raw peanuts had higher (P less than .05) milk protein than sows fed 5% animal fat. Sows farrowing in the summer had greater (P less than .01) weight loss and consumed less (P less than .05) feed during lactation than sows farrowing in the winter. Sows farrowed in the summer had larger (P less than .05) litters at birth and 14 d postfarrowing and greater (P less than .10) piglet and litter weight gain postfarrowing than those farrowed in the winter.(ABSTRACT TRUNCATED AT 250 WORDS)     

Impact of amino acid nutrition during lactation on body nutrient mobilization and milk nutrient output in primiparous sows.

The impact of amino acid nutrition during lactation on body nutrient mobilization and milk nutrient output in primiparous sows was evaluated. Thirty-six sows, nursing litters of 13 pigs, were allocated daily 6 kg of a fortified corn-soybean meal diet containing a high (HP, 1.20% lysine) or low (LP, .34% lysine) protein content during a 23-d lactation. Dietary lysine concentration was achieved by altering the ratio of corn and soybean meal in the diet. The LP sows consumed less daily ME (14.2 vs 16.1 Mcal; P < .11) and daily lysine (16 vs 59 g; P < .01) than the HP sows. Daily litter weight gain was less (P < .01) for sows fed the LP vs HP diet, and the differences increased (P < . 01) as lactation progressed. The lower litter weight gain for the LP sows was reflective of the lower (P < .01) estimated milk DM, CP, and GE output of these sows. The LP sows lost more body weight (1.23 vs .21 kg/d; P < .01) during the initial 20 d of lactation. In the LP sows, 59% of the weight loss was protein, water, and ash, and 37% was fat. Weight loss in the HP sows was entirely accounted for by body fat mobilization, because these sows accrued body protein, water, and ash. Muscle myofibrillar breakdown rate was higher in LP sows than in HP sows (4.05 vs 2.80%/d; P < .01). On the basis of these data, dietary amino acid restriction during lactation increases maternal mobilization of proteinaceous tissue and reduces milk nutrient output. Maternal protein mobilization is maintained over the entire lactation even though milk output is decreased as lactation progresses.     

Effects of feeding sows fat or fructose during late gestation and lactation

The effects of dietary fat or fructose supplementation during late gestation and lactation on sow milk production and composition and on progeny were examined. On d 88 of gestation, 24 sows were allotted by parity to three dietary treatments (eight sows/treatment). Treatments were 1) a 12.5% crude protein, corn-soybean meal control, 2) the control + 10% added fat or 3) the control + 23% high fructose corn syrup. All treatments were fed to supply 1.82 kg/d of the control diet from d 89 of gestation to parturition with sows in treatments 2 or 3 receiving .18 kg of additional fat or .53 kg of additional high fructose corn syrup, respectively. Feed was gradually increased from d 1 to 7 of lactation to 4.54 kg/d of the control diet (plus .45 kg of added fat and 1.33 kg of added fructose for treatments 2 and 3) and remained at these levels for the remainder of the 21 d lactation period. All treatments were iso-nitrogenous; treatments 2 and 3 were iso-caloric. Litter birth weights, number of pigs born alive, weaning weights and piglet survival rate were not affected by sow treatment. Stillbirths were less (P less than .05) for sows fed fat. Lipid content of milk 24 h post-farrowing was greater (P less than .05) from sows fed fat compared with sows fed fructose. Milk production estimates indicated that multiparous sows fed fat produced more (P less .05) milk than sows fed the control diet. On d 112 of gestation and d 15 of lactation, serial blood samples were drawn to monitor sow response to a glucose challenge (1 g/kg body weight).(ABSTRACT TRUNCATED AT 250 WORDS)     

The effects of dietary fat or fiber addition on yield and composition of milk from sows housed in a warm or hot environment

Sixty sows were individually penned in a thermoneutral (20 degrees C) or hyperthermal (32 degrees C) environment and fed a basal (corn-soybean meal), high-fiber (48.5% wheat bran) or high-fat (10.6% choice white grease) diet from d 100 of gestation through a 22-d lactation. The diets were determined to contain 3.28, 2.76 and 3.75 Mcal ME/kg, respectively. All pigs received 8.0 Mcal of ME and 17.5 g of lysine daily prior to parturition and were allowed to consume their respective diets ad libitum after parturition. Litter size was standardized at 9 to 10 pigs by d 2 postpartum. Milk yields were determined for five, 4-d periods from about d 2 through 22 of lactation via a D2O dilution technique. Daily milk yield and litter weight gain began to plateau, and the efficiency of utilizing milk DM and milk energy for gain was depressed (P less than .01), in the latter stages of the lactation. Heat exposure (32 degrees C) reduced (P less than .05) voluntary ME intake and milk energy yield of the sow and increased (P less than .05) the sow's weight loss during lactation. In the hot environment, increasing dietary energy concentration resulted in a linear (P less than .08) increase in milk fat content and milk energy yield over the duration of the 22-d lactation. In the latter stages of lactation, pigs consuming high-fat milk required more (P less than .09) milk and milk energy per unit of weight gain. In the warm environment, milk energy yield was increased by dietary fat or fiber additions in early lactation, but not in late lactation. These results indicate that the effects of thermal heat stress on sow milk energy yield and litter weight gain are aggravated by dietary fiber addition and minimized by dietary fat addition.     

Dietary medium- or long-chain triglycerides improve body condition of lean-genotype sows and increase suckling pig growth

In a field trial conducted on a commercial swine farm, lean-genotype sows (n = 485) were fed diets containing 0 or 10% supplemental fat as either medium-chain triglyceride or choice white grease from d 90 of gestation until weaning (15.5 d). Effects on standard sow and litter production traits were examined together with assessment of sow body condition using live ultrasound. Daily feed intake during lactation was 10% higher in sows consuming diets without added fat (7.2 vs 6.5 kg; P < 0.01); however, lactation ME (23.9 Mcal/d) and digestible lysine (54 g/d) intakes were unaffected (P > 0.10). Sows supplemented with fat were 4 kg heavier on d 109 of gestation (220 vs 224 kg; P < or = 0.01), 1 d after farrowing (210 vs 214 kg; P < or = 0.01), and at weaning (210 vs 214 kg; P < or = 0.01). Expressed as overall gain, this amounted to a 23% increase (0.66 vs 0.86 kg/d; P < or = 0.01) and was accompanied by a 49% increase in backfat (0.82 vs 1.68 mm; P < or = 0.03) from d 90 to farrowing. Changes in sow weight (-0.01 kg/d) and backfat (+4.2 mm) over lactation were minimal and were not affected by fat supplementation (P > or = 0.10). Longissimus muscle area at weaning was slightly greater (44.96 vs 46.2 cm2) in sows consuming fat than in control sows (P < or = 0.05), but changes in longissimus muscle area were not significant from d 90 to weaning (P > or = 0.10). Gestation length, pigs born alive, average birth weight, survival (d 3 to weaning), and days to estrus were not affected by diet (P > 0.10). However, supplemental fat increased pig ADG (192 vs 203 g/d; P < 0.01) and average pig weaning weight (4.3 vs 4.5 kg) at 15.5 d (P < or = 0.02). No differences between the two fat sources were detected. This large-scale study demonstrated that supplemental fat during gestation and lactation effectively improved sow condition and improved suckling pig performance without affecting energy intake during lactation, implying improved efficiency of sow energy utilization.     

The influence of suckling interval on milk production of sows

The objective of this study was to determine whether sow milk yield per gland could be increased by reducing the interval between suckles (suckling interval). Eighteen sows were allocated at their first farrowing to three treatments comprising litter sizes of 6 or 12 piglets or a cross-suckling treatment that was imposed to increase suckling frequency. The cross-suckled treatment comprised two groups of six piglets each. Each suckling group was allowed to suckle the sow during 30-min intervals each day between d 6 and d 28 of lactation. The suckling interval was shorter (P < .05) for cross-suckled sows than for sows suckling single litters of 6 or 12 piglets during early lactation (d 10 to 14) and late lactation (d 24 to 28). Average piglet growth rate between birth and 28 d of age was greatest (P < .05) for piglets in the single litters of six and lowest for piglets in the cross-suckled treatments. Single litters of 12 piglets had the highest (P < .05) litter growth rates, followed by the cross-suckled litters and then the single litters of six piglets. The concentration of lactose and fat in milk from sows remained relatively stable, although milk from the cross-suckled sows contained more protein in early lactation (P < .05). Milk yield of sows was not significantly increased (P > .05) by the cross-suckle treatment, although during early lactation, milk yield tended to be greater from sows in the cross-suckle treatment than from sows suckling single litters of six (8,920 g/d vs 7,819 g/d, P < .1). The concentration of DNA and total RNA and the RNA:DNA ratio in mammary glands was unaffected by treatment (P > .05). Sows with single litters of 12 piglets had the greatest total DNA in their udders (P < .05). However, individual gland weights were heavier (P < .05) in cross-suckled sows than in sows with single litters of 6 or 12 piglets. Increased suckling frequency seemed to play a role in increased mammary gland weight and milk production during lactation.     

Protein and fat utilization in lactating sows: I. Effects on milk production and body composition

In order to provide data with which to challenge a model of metabolism of lactating sows, we conducted a study to determine milk production and body and mammary composition in sows consuming a range of energy and amino acid intakes and nursing 11 to 12 pigs. Sows (2nd through 4th parity) consumed the same ration during gestation and consumed 6.1 kg/d (as-fed) for a 20 d lactation. Litter size was standardized at 12 pigs within 3 d of farrowing. Diets were formulated to provide three different amounts of protein intake and two different amounts of fat intake. Protein intakes of sows in high (HP), medium (MP), and low protein (LP) treatment groups were 863, 767, and 678 g/d with 59, 53, and 47 g/d lysine at two levels of fat intake, 117 (LF) and 410 g/d (HF). Number of pigs weaned per litter was 11.4 +/- 0.5 and milk production and litter weight gain was less (P < 0.01) in the last week of lactation for sows consuming the least protein. Medium and low protein intakes increased (P < 0.05) loss of body lean and protein. Change in carcass protein during lactation was -1.4, -3.0, -2.2, -1.2, -1.9 and -2.1 kg (SD 2.6) for sows fed HPLF, MPLF, LPLF, HPHF, MPHF, and LPHF. Body fat (carcass and visceral) change was 0.4, -3.7, -4.1, -0.3, 3.4, and -1.3 kg (SD 6.6) in HPLF, MPLF, LPLF, HPHF, MPHF, and LPHF groups. Total amount of mammary parenchyma increased more (P < 0.05) in sows fed a higher fat diet. These data are consistent with general knowledge of changes in body composition in lactation of sows. However, changes in body protein and fat were correlated across treatments and different from that reported for sows nursing smaller litters. These data help our quantitative understanding of nutrient flux in sows nursing large litters and allow a severe challenge of existing models of metabolism in sows.     

Influence of duration of litter separation and boar exposure on estrous expression of sows during and after lactation

The influence of litter separation (LS) that included a change in housing environment and social status of sows, boar exposure (BE), and parity on estrous expression by sows during and after lactation was examined in two experiments utilizing 140 crossbred sows. In Exp. 1 (Yorkshire X Duroc sows), limiting duration of LS to 6 or 3 h/d during the last 8 d of lactation in two trials, while maintaining 1 h BE, resulted in similar proportions of sows in estrus during lactation (65 vs 79% for 3- and 6-h sows). However, 6-h LS tended to reduce (P = .08) the interval to estrus by .6 d for those sows that expressed a preweaning estrus. Postweaning intervals to estrus were unaffected by duration of LS in the remaining sows. In Exp. 2, sows (Yorkshire X Duroc X Chester White) were assigned to four treatment groups during the last 8 d of lactation: 1) BE (1 h/d), 2) LS (6 h/d), 3) LS + BE and 4) no LS + no BE (control). Only nine sows expressed estrus during lactation; four of 28 LS sows and five of 28 LS + BE sows. No sows were in estrus before weaning during August 1985 and only one sow (LS group) was in estrus before weaning during October 1986. Postweaning intervals to estrus were reduced (P less than .05) by .9 d after preweaning BE compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS)     

皖南花猪泌乳力的研究

抽选２～９胎次的皖南花哺乳母猪６头,每头母猪带仔１０～１４头,有效乳头数７对。试验母猪日粮含ＤＥ１１．７２ＭＪ／ｋｇ和ＣＰ１２％,取日粮２．５～３．０千克,按１２与青绿多汁饲料混合打匀投喂。供试母猪自分娩开始,每５天进行一次泌乳量测定,直到产后泌乳５０天。利用线性模型校正不同胎次和带仔数的泌乳量,再采用一元高次方程进行泌乳曲线分析。结果表明,皖南花猪泌乳高峰期在分娩后的第１０～１５天,其间平均泌乳量为５．６６～５．９１ｋｇ／天,分娩后的第３５天泌乳量为３．７ｋｇ／天。不同乳头的泌乳量为第１、２和３号乳头最高,平均每个单乳头泌乳３８０～３８５ｇ／天,向后乳头的泌乳量呈下降趋势,第７号乳头泌乳量为３００．５ｇ／天。不同泌乳阶段表现出明显的节律性,泌乳曲线方程的拟合度均在０．９０以上。     

Influence of energy and protein intake during lactation on body composition of primiparous sows

The effects of energy and protein intakes by 32 primiparous sows during a 28-d lactation on sow and litter performance and sow body composition and bone properties were examined. Dietary treatments were energy intakes of 8 (LE) and 16 (HE) Mcal of ME/d and protein intakes of 380 (LP) and 760 (HP) g of CP/d in a 2 x 2 factorial arrangement. Sows fed diets that were inadequate in either energy or protein lost more weight than did sows fed the HE-HP diet, but backfat losses were greater when energy intake was deficient than when protein was deficient. Carcass measurements were influenced in a similar manner, with energy intake affecting (P less than .001) backfat thickness and protein intake affecting (P less than .05) longissimus muscle area. Heart, kidneys and liver of sows fed LP diets weighed less (P less than .01) and contained less water and protein (P less than .05) than those of sows fed HP. Sows fed LE had heart, liver and viscera that weighed less (P less than .05) than those of sows fed HE. There was less fat (P less than .05) in the heart, lung, liver and viscera of sows fed LE than in those of sows fed HE. Carcass components of the supraspinatus muscle and standardized sections through the longissimus muscle and right shoulder weighed less (P less than .05) from sows fed LP rather than HP, and these components contained less water and protein. Sows fed the LE diets had less fat in the loin soft tissue section, right shoulder section and supraspinatus muscle than sows fed HE. Bone composition and strength were not influenced by dietary treatment. The composition of weight lost during lactation was diet-dependent. Sows fed diets that were deficient in protein but adequate in energy lost large amounts of protein from muscles and internal organs. Energy deficiency resulted primarily in fat loss.     

Improving sow productivity through management during gestation, lactation and after weaning

Number of pigs produced per sow per year is dependent upon the number of pigs born live, the number that survive to weaning and the interval between consecutive farrowings for the sow. Feeding and management of the sow during late gestation affects birth weight and amount of energy stored as glycogen and lipid in the piglet. Piglets that are heavier and that have more energy stores have a higher survival rate. Adding fat to the sow's diet during the last month of gestation or altering the sow's metabolism to direct more nutrients to the fetus are methods for increasing piglet birthweight and energy stores. Feeding the sow properly during lactation is important for maximum yield of milk and milk energy, which affects survival of pigs to weaning, and for rebreeding performance of the sow after weaning. Energy intake during lactation can be increased by adding fat to diets, and this is beneficial in situations where feed intake is insufficient to meet the sow's requirements. For example, fat supplementation during lactation is beneficial for primiparous sows and for sows lactating during hot weather. The minimum practical lactation length is about 2 wk for normal rebreeding performance of the sow. Split weaning or separation of the litter from the sow for 6 to 12 h/d will shorten the rebreeding interval or induce estrus during lactation. Administration of pregnant mare's serum gonadotropin, with or without human chorionic gonadotropin, will induce estrus during lactation, and the response is better after the second week of lactation. Similar treatments at weaning will shorten the rebreeding interval.(ABSTRACT TRUNCATED AT 250 WORDS)     

Energy balance of lactating primiparous sows as affected by feeding level and dietary energy source

The effects of feeding level and major dietary energy source used during lactation on sow milk composition, piglet body composition, and energy balance of sows were determined. During a 21-d lactation, 48 primiparous sows were fed either a Fat-rich (134.9 g/kg fat; 196.8 g/kg carbohydrate) or a Starch-rich (33.2 g/kg fat; 380.9 g/kg carbohydrate) diet at either a High (44 MJ NE/d; 1,050 g protein/d) or a Low (33 MJ NE/d; 790 g protein/d) feeding level. Within each feeding level, the two diets were fed to provide an isocaloric and isonitrogenous intake. At the Low feeding level, no differences in milk production, milk composition, or piglet body composition were found as a result of feeding the two dietary energy sources. However, at the High feeding level, sows fed the Fat-rich diet produced higher milk fat (8.4 vs 6.9%) and milk energy (5.38 vs 4.77 kJ/g) concentrations and a higher piglet body fat concentration (152.1 vs 135.4 g/kg) than sows fed the Starch-rich diet. At the Low feeding level, the energy balance (d 6 to d 20) of the sows was similar when fed either the Fat- or the Starch-rich diet (-558 and -515 kJ x BW(-.75) x d(-1)), but at the High feeding level, the energy balance was more negative in sows fed the Fat than those fed the Starch-rich diet (-544 vs -372 kJ x BW(-.75) x d(-1)). This suggests that at the High feeding level, dietary energy in the form of fat is preferentially used for milk fat synthesis, resulting in growth and in fatter piglets. Alternatively, at the High feeding level, Starch as the major energy source is used only for growth of the piglets, as confirmed by protein deposition, and also results in a less-negative energy balance for the sows. From this experiment, it can be concluded that effects of substituting cornstarch for fat in the diet of lactating sows on milk composition, piglet body composition, and energy balance of the sows are dependent on feeding level.     

Effect of dietary energy intake during lactation on performance of primiparous sows and their litters

A total of 146 primiparous sows was used in four replications of an experiment to investigate the effect of energy intake during a 28-d lactation on sow and litter performance. Dietary treatments consisted of three energy intakes; 10, 12 or 14 Mcal of metabolizable energy (ME) X sow-1 X d-1. All sows were fed equal amounts of crude protein, vitamins and minerals daily, which met or exceeded standard recommendations. The experiment was initiated at parturition. Sow weight and backfat loss during lactation decreased linearly (P less than .001) as energy intake increased. There were no differences in litter size at either 14 d of lactation or weaning. Pig weights on d 14 increased linearly (P less than .05) and litter weights tended to increase linearly (P = .13) as energy intake increased. At weaning, pig weights and litter weights increased (P less than .05) as sow energy intake increased. There were no significant differences in the percentages of sows in estrus by 7, 14, 21 and 70 d postweaning, but sows fed 10 Mcal ME/d had a slightly longer interval from weaning to first estrus than sows fed higher energy intakes. Serum urea concentrations of sows were inversely related to energy intake during lactation. Serum creatinine concentrations were not affected by energy intake. An intake of 10 Mcal ME/d by primiparous sows during a 28-d lactation resulted in reduced sow and litter performance; there was little difference between sows fed 12 and 14 Mcal ME/d.     

Effects of genetic line and supplemental dietary fat on lactation performance of Duroc and Landrace sows.

A total of 124 Duroc and 99 Landrace primiparous and multiparous sows were assigned, within breed and contemporary group, to control (N) or 10% added fat (F) diets on d 105 of gestation based on parity and genetic line (control or selected for improved sow productivity), to determine the effects of genetic line and fat addition to the lactation diet on sow and litter performance. Weekly feed intake was not affected (P greater than .10) by genetic line for Duroc and Landrace sows but feed intake was reduced (P = .08) during wk 1 to 4 for Duroc sows and during wk 1 and 4 for Landrace sows (P less than .05) when they were fed diet F compared with diet N. Select (S)-line Duroc and Landrace sows lost more weight during lactation (P less than .01) than did control (C)-line sows. Select-line Landrace sows lost more backfat during lactation (P less than .05) than did C-line sows. Landrace sows lost less weight during lactation (P less than .05) when fed diet F than when fed diet N. The total number of pigs born, born alive, and alive at 21 d and at weaning were higher (P less than .01) for S-line Duroc sows, and litter size at 21 d and at weaning was higher (P less than .01) for S-line Landrace sows than for C-line litters within each breed. Pig survival from birth to weaning was increased (P = .07) for Duroc sows fed diet F but not for Landrace sows.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of teat position on selected milk components of primiparous sows during lactation

The composition of sow colostrum and milk from single teats were characterized in 20 primiparous German Landrace sows at ten points throughout lactation time (after birth of the first piglet, and subsequently at 12 and 24 h, 3, 5, 7, 14, 21, 28 and 35 d postpartum). In these samples contents of protein, IgG, lactose and fat were analyzed. In the first 3 days of lactation protein- and IgG-contents drastically decreased, on the other hand the levels of energy resources lactose and fat increased. Significant effects of the single teat and the teat pair on the content of protein at farrowing and 12 h later as well as on the contents of IgG and lactose 12 h postpartum were found. The highest contents of protein and IgG were analyzed in colostrum of teats in the median udder section, the colostrum of cranial teats had the highest content of lactose. At days 3 and 5 of lactation milk showed large coefficients of variation (cv) in milk composition from teat to teat as well as from sow to sow (intraindividual cv: protein: 22%, IgG: 45%, lactose: 20%, fat: 34%; interindividual cv: protein: 36%, IgG: 85%, lactose: 27%, fat: 47%). During lactation period the intraindividual variation of milk parameters was lower than the interindividual variation. Possible reasons for these results are discussed.     

Value of raw soybeans and soybean oil supplementation in sow gestation and lactation diets: a cooperative study

A cooperative study using 215 sows during two parities (349 litters) was conducted at six stations to determine the effect of raw soybeans in gestation and lactation diets on sow and litter performance. Sows were bred and allotted to fortified corn diets containing either soybean meal (control) or raw soybeans. A corn-soybean meal-soybean oil diet, isocaloric to the raw soybean diet, was included as a third treatment at three stations. All diets contained 14% CP. These diets were fed during both gestation and lactation through two parities. The daily gestation feed intake ranged from 1.8 to 2.3 kg/sow, depending on station. During lactation, the sows were allowed ad libitum access to their respective diets. Gestational weight gain was not influenced by diet, but sows fed raw soybeans consumed less (P less than .01) feed during lactation and had greater (P less than .01) lactational weight loss and their pigs were lighter in weight (P less than .05) both at 21 d and at weaning (varied between 3 and 5 wk of age). Sows fed the diet with supplemental oil had reproductive and lactational performance similar to those fed the control diet. Milk obtained at d 10 to 14 of lactation from sows fed raw soybeans had lower (P less than .05) protein content than milk from sows fed the other two diets, but fat content of the milk tended to be increased by raw soybeans or by added soybean oil. Return to estrus was not affected by diet.(ABSTRACT TRUNCATED AT 250 WORDS)     

Lactational variation and relationship to postnatal growth of insulin-like growth factor-I in mammary secretions from genetically diverse sows

Mammary secretions obtained from four groups of sows at parturition and on days 7, 14 and 21 of lactation were defatted and assayed for total protein and insulin-like growth factor-I (IGF-I). Sows (n = 57) represented two breeds (Landrace and Duroc) and two genetic lines (selected for differences in sow productivity index, SPI) within each breed. Colostrum of Duroc sows was 4-6 fold and 30-60 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk from these sows. In contrast, the colostrum of Landrace sows was 2-3 fold and 30-50 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk. The IGF-I content in milk from Duroc sows did not differ among days 7, 14 and 21 of lactation, whereas the IGF-I content of day 7 milk from Landrace sows exceeded those for the corresponding 14 day and 21 day secretion (P less than .05). IGF-I concentration in days 14 and 21 milk was higher in Duroc (P less than .001 respectively) than Landrace sows. No significant differences in total protein or IGF-I content of mammary secretions were observed between the selected and control lines within each breed.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of fructose consumption during lactation on sow and litter performance and sow plasma constituents

The effects of dietary consumption of high-fructose corn syrup (HFCS) and dextrose during a 28-d lactation on sow and litter performance and sow plasma constituents were examined in 45 multiparous and 36 primiparous crossbred sows. Isocaloric and isonitrogenous corn-soybean meal diets were formulated to contain either 20% fructose or 20% glucose. Diets were fed on a metabolic BW basis from d 0 to d 28 of lactation. Litter and pig weights on d 28 were not affected (P greater than .05) by treatment. Litter size was greater (P less than .10) at weaning for primiparous sows fed HFCS, but multiparous sows weaned heavier (P less than .05) pigs. Sow weight change during lactation was not influenced by diet, but primiparous sows lost more (P less than .05) weight during lactation and had longer intervals to estrus than multiparous sows did. Milk yields on d 17 and 21 of lactation were not different (P greater than .05) for sows fed HFCS vs dextrose, but sows fed HFCS tended to have greater (P = .05) percentage of milk fat. Preprandial concentrations of fructose in plasma were low in sows fed HFCS and nondetectable in those fed dextrose but were elevated (P less than .05) after consumption of HFCS. Conversely, similar (P greater than .05) concentrations of glucose in plasma preprandially were followed by greater (P less than .05) postprandial glucose concentrations in sows fed dextrose. Although postprandial concentrations of insulin were not affected (P greater than .05) by diet, sows fed dextrose had greater (P less than .05) preprandial insulin concentrations in plasma. Concentrations of nonesterified fatty acids and growth hormone in plasma and response to a glucose challenge were not affected (P greater than .05) by feeding HFCS. However, concentrations of insulin in plasma following glucose infusion were less (P less than .05) during the glucose challenge period on d 25 than on d 13 of lactation.     

Impact of diet deprivation and subsequent over-allowance during prepuberty. Part 2. Effects on mammary gland development and lactation performance of sows

The impact of diet deprivation and subsequent over-allowance in prepubertal gilts on their mammary development and mammary gene expression at the end of gestation and their lactation performance over 2 parities was determined. Seventy-seven gilts were reared under a conventional (control, CTL; n = 41) or an experimental (treatment, TRT; n = 36) dietary regimen. The experimental regimen provided 70 (restriction diet, RES) and 115% (over-allowance diet, OVER) of the protein and DE contents provided by the CTL diet. Experimental diets were fed ad libitum starting at 27.7 ± 3.4 kg of BW as follows: 3 wk RES, 3 wk OVER, 4 wk RES, and 4 wk OVER. All gilts were bred, and 34 were slaughtered on d 110 of gestation (18 CTL and 16 TRT) to collect mammary tissue for compositional analyses and gene expression measurements. Remaining gilts (23 CTL and 20 TRT) were maintained for 2 parities, and litter performance data were obtained. Blood samples for hormonal and metabolite assays were obtained on d 110 of gestation from all sows slaughtered at that time and from 14 sows per treatment on d 2 and 17 of lactation in the first parity. Milk samples were obtained from these same sows on d 17 of lactation in both parities. There was a tendency for mammary parenchymal tissue to contain less protein in TRT than CTL sows (P < 0.10), and relative mRNA abundance of the signal transducer and activator of transduction 5B gene was increased in parenchyma from TRT sows (P < 0.05). Circulating prolactin (P < 0.05) and milk lactose concentrations (P < 0.01) were less, whereas milk protein content was greater (P < 0.05) in TRT sows than CTL sows on d 17 of lactation. Nevertheless, growth rate of suckling piglets over the first 2 parities was unaffected by treatment. In conclusion, the use of a diet deprivation and over-allowance regimen in the growing-finishing period did not have beneficial effects on mammary gene expression or on sow and piglet performance.