Dietary probiotic supplementation and resulting effects on performance, health status, and microbial characteristics of primiparous sows

In an experiment with 33 first-litter sows from day 90 of pregnancy to day 28 of lactation, the influence of a probiotic supplementation on weight performance, feed intake, litter sizes, litter weights, health status and microbiological profile was tested. Enterococcus faecium DSM 7134 was supplemented in a concentration of 5 x 10(8) CFU/kg feed to the gestation and lactation diets of gilts. The supplemented sows showed a significant higher improvement of feed intake (4.16 vs. 3.71 kg/day), litter size (9.2 vs. 7.7 piglets) and weight performance. The average live weight of the probiotic sows at day 28 of lactation was 11 kg higher than of the controls. The bacterial counts/g faeces (lactobacilli, Gram-positive anaerobes, Gram-negative anaerobes, Escherichia coli and enterococci) and the incidence of adhesive and haemolytic E. coli organisms revealed no significant differences between the sows of the two groups or their piglets. While the litter size cannot necessarily be assumed as a primary effect of the probiotic supplementation, the significantly better feed intake and weight performance might be partly due to the probiotic use and can prevent "starvation sterility" of young sows after their first litter caused by reduced feed intake during lactation with high mobilization of body tissue accompanied with lack of energy.     

Antibody-dependent and spontaneous cell-mediated cytotoxicity against transmissible gastroenteritis virus infected cells by lymphocytes from sows, fetuses and neonatal piglets.

The purpose of this study was to investigate the ontogeny in the pig of effector lymphocytes mediating antibody-dependent and spontaneous cell-mediated cytotoxicity against target cells infected with transmissible gastroenteritis virus. The same activities were also studied in sows in late pregnancy and early lactation. Peripheral blood lymphocytes and intraepithelial lymphocytes collected from piglets during the first week of life failed to mediate cytolysis as determined by chromium release assays, but significant activities developed during the second week and usually increased further by the sixth week. Peripheral blood lymphocytes collected from fetuses on the 109th gestation day failed to produce spontaneous cell-mediated cytotoxicity and only reacted in antibody-dependent cell-mediated cytotoxicity when contaminated with macrophages. The cytotoxic activities of peripheral blood lymphocytes from sows were lowest at parturition. It was concluded that impaired lymphocyte cytotoxicity in newborn piglets and parturient sows may contribute to their relatively high susceptibility to transmissible gastroenteritis.     

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.     

Performance of sows fed high levels of nonstarch polysaccharides during gestation and lactation over three parities

The effect of feeding sows a starch diet or a diet with a high level of nonstarch polysaccharides (NSP) during gestation, lactation, or both gestation and lactation during the first three parities on reproductive performance, body weight, and backfat was studied. Four-hundred and forty-four postpuberal gilts were allotted to a 2 x 2 x 2 factorial experiment. Treatments were diet composition during gestation (including the weaning-to-estrus interval; G-Starch: 274 g/kg of starch and 123 g/kg of fermentable NSP or G-NSP: 86 g/kg of starch and 300 g/kg of fermentable NSP), diet composition during lactation (L-Starch: 293 g/kg of starch and 113 g/kg of fermentable NSP or L-NSP: 189 g/kg of starch and 216 g/kg of fermentable NSP) and group-housing system during gestation (free access stalls or electronic feeding). Both gestation diets were formulated to be isoenergetic. During lactation, sows were given free access to the lactation diets from d 6 after parturition onwards. Body weight and backfat gains during gestation were lower in sows fed the G-NSP diet than in those fed the G-starch diet (P < 0.001). The effects were more pronounced in the electronic feeding system than in the free access stalls. These results indicate an overestimation of the energy value of fermentable NSP. Body weight and backfat losses during lactation were less in sows fed the G-NSP diet during gestation than in those fed the G-starch diet (P < 0.05),which can be explained by a 0.4 kg/d higher (P < 0.001) feed intake during lactation of the sows fed the G-NSP diet. Sows fed the L-NSP diet lost more backfat during lactation than sows fed the L-starch diet (P < 0.05). The number of total piglets born and live-born piglets was 0.5 piglet higher in sows fed the G-NSP diet than in those fed the G-starch diet (P < 0.05). Lactation diet did not affect the number of total piglets born or live-born piglets. This study shows that, although high NSP diets negatively influence body weight and backfat thickness of the sows, it is possible to feed sows a diet with a high level of fermentable NSP diet during both gestation and lactation without negative effects on reproductive performance. Under the conditions of this study, feeding sows a diet with a high level of fermentable NSP during gestation and a high level of starch during lactation seems the most favorable feeding strategy.     

Effect of L-carnitine supplementation on performance parameters in gilts and sows

The effect of L-carnitine supplementation during pregnancy and lactation on performance parameters of sows was studied. The trial comprised a total of 127 sows (40 gilts, 87 mature sows) which were divided into a control and a treatment group. All animals were fed individually and received basic feed mixtures for pregnancy and lactation with low carnitine concentrations (gestation diet: 4.7 mg/kg feed, lactation diet: 12.5 mg/kg feed). The rations of the sows in the treated group were supplemented with 125 mg L -carnitine per head and day during pregnancy and 250 mg L -carnitine per head and day during lactation. The animals of the control group received identical feed mixtures in identical amounts, but without the L -carnitine supplement. L -carnitine supplementation resulted in higher sow liveweight gains between day 1 and day 85 of pregnancy. The number of piglets per litter and the number born alive did not differ between the control sows and those treated with L -carnitine. However, the L -carnitine-supplemented sows produced only half as many non-viable piglets as the control animals. Moreover, litter weight and mean birth weight of piglets from L -carnitine-treated sows were higher than in the control sows. This effect was more marked in gilts (+8% higher litter weight, +9% higher piglet weight) than in sows (+7% and +6%, respectively). Piglets from sows whose ration was supplemented with L -carnitine showed higher liveweight gains during the suckling period (+12% for gilts, +4% for sows), which is why litter weights post weaning were also higher among the sows treated with L -carnitine than in the control sows (+14% for gilts, +10% for sows). Overall, the study shows that dietary supplementation with L -carnitine during pregnancy and lactation improves the reproductive performance of sows.     

Effects of alpha-lipoic acid supplementation on antioxidative ability and performance of sows and nursing piglets

The current study was carried out to determine the effects of alpha‐lipoic acid (LA) supplementation during late‐gestation and lactation on antioxidative ability and performance of sows and their nursing piglets. A total of 160 multiparous sows were randomly allocated to four treatments with 40 replicates per treatment according to parity number and backfat (BF) thickness. Sows were fed 1 of 4 diets from day 85 of gestation to day 21 of lactation. Diets were control without LA; 400 ppm LA supplementation; 600 ppm LA supplementation; and 800 ppm LA supplementation. BF thickness of sows was determined on day 85 and 110 of gestation and days 1 and 21 of lactation. Piglet bodyweight was measured at birth, days 7, 14 and 21. Blood samples were obtained from the sows, and average daily feed intake (ADFI) of the sows during lactation was recorded. There were no differences in BF thickness or ADFI among treatment groups. Dietary LA supplementation resulted in a decrease in blood urea nitrogen (p < 0.01) concentration at days 110 of gestation. Dietary 800 ppm LA increased serum glutathione peroxidase (GSH‐Px) activity (p < 0.05) and reduced maleic dialdehyde levels (p < 0.01) of sows compared with the control diet at days 21 of lactation. Alpha‐lipoic acid supplementation increased the birthweight and weaning weight of piglets (p < 0.01) compared with the control group. Weight gains of piglets from sows fed the 800 ppm LA diets were greater (p < 0.01) between days 7 and 14 compared with piglets from control sows. Weight gains of piglets from sows fed the LA‐supplemented diets were greater between days 14 and 21 (p < 0.05) and between days 1 and 21 (p < 0.01) compared with piglets from control‐fed sows. In conclusion, the results indicate that antioxidant LA was effective in enhancing antioxidant enzymes activity and improving the performance of sows and their nursing piglets.     

The use of different vaccination schedules for sows to protect piglets against Aujeszky's disease

Several Aujeszky's disease virus (ADV) vaccination protocols of sows were evaluated with regard to the passive protection conferred on piglets in a recently built commercial farm. Three different groups of sows were vaccinated using a Bartha K-61 strain. One group received an inactivated vaccine during pregnancy and the other two groups received attenuated vaccines, either during pregnancy (day 65) or on the seventh day of lactation. At farrowing, sows vaccinated during lactation had lower seroneutralization titres than those vaccinated during pregnancy either with inactivated or attenuated vaccines. Accordingly, their piglets were the ones with lower levels of maternally transferred neutralizing antibodies. At 4 weeks of age, five piglets born of each group of sows were challenged intranasally with a neurotropic strain of ADV. Piglets born of sows vaccinated during pregnancy with inactivated and attenuated vaccines gained 1.50 kg bodyweight and 2.50 kg bodyweight during 7 days, respectively, and did not show clinical signs, while piglets from sows vaccinated during the previous lactation lost 0.60 kg and presented moderate to severe clinical signs of ADV. Vaccination of sows during pregnancy provided more protection against ADV for piglets than sow vaccination before mating. Piglets born from sows vaccinated with attenuated or inactivated vaccines did not present remarkable differences on protection.     

Live yeast supplementation during late gestation and lactation affects reproductive performance,colostrum and milk composition,blood biochemical and immunological parameters of sows

This study was conducted to evaluate the effects of dietary live yeast (LY) supplementation during late gestation and lactation on reproductive performance, colostrum and milk composition, blood biochemical and immunological parameters of sows. A total of 40 multiparous sows were randomly fed either the control (CON) diet or the CON diet supplemented with LY at 1 g/kg from d 90 of gestation to weaning. Results showed that the number of stillborn piglets and low BW piglets were significantly decreased in the LY-supplemented sows compared with sows in the CON group (P < 0.05). Moreover, the concentrations of protein, lactose and solids-not-fat were increased in the colostrum of LY-supplemented sows (P < 0.05). Interestingly, the plasma activities of aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (γ-GGT) at d 1 of lactation and alanine aminotransferase (ALT) at weaning day were decreased by feeding LY diet (P < 0.05). Meanwhile, sows fed LY diet had higher plasma concentration of immunoglobulin G compared with sows fed CON diet at d 1 of lactation (P < 0.05). In conclusion, LY supplementation in maternal diets decreased the number of stillborn piglets and low BW piglets, improved colostrum quality and health status of sows.     

复合有机铁对母猪繁殖性能和仔猪生长性能的影响

通过在怀孕后期和哺乳期母猪日粮中添加不同水平的硫酸亚铁和复合有机铁,以及肌注铁与否来考察复合有机铁对母猪繁殖性能和仔猪生长性能的影响。结果表明,与无机铁相比,母猪饲粮中添加复合有机铁可提高母猪产活仔率和断奶仔猪存活率,提高仔猪10日龄、21日龄体重;综合铁源、铁水平以及肌注补铁的效应,添加120 mg/kg复合有机铁,同时仔猪均辅以肌注补铁,可显著提高仔猪肌注7日龄和断奶时体重(P<0.05)。     

Effects of dietary arginine supplementation during gestation and lactation on the performance of lactating primiparous sows and nursing piglets

A 2 x 2 factorial arrangement of treatments in a randomized block design was used to determine the effects of dietary Arg supplementation during gestation and lactation on the lactation performance of 38 first-parity sows. At 30 d of gestation, pregnant gilts were allotted based on BW to 1 of 2 diets supplemented with 1% L-Arg.HCl or 1.7% L-Ala (isonitrogenous control). After farrowing, sows were further allotted based on BW within previous gestation treatment groups to 1 of 2 lactation diets supplemented with 1% L-Arg.HCl or 1.7% L-Ala (isonitrogenous control). All gestation diets contained 3.1 Mcal/kg and 12.2% CP (as is) and were fed 2 kg/d in 2 equally sized meals, whereas all lactation diets contained 3.2 Mcal/kg and 18.6% CP (as is) and were fed ad libitum. Litter size was standardized to 10 piglets by cross-fostering within 24 h postfarrowing. On a weekly basis, BW and backfat (BF) thickness of sows, as well as piglet BW were measured, and blood and milk samples were obtained from the sows. Number of days from weaning to estrus and ADFI were also recorded. There were no differences in BW, BF thickness, ADFI, or days until return to estrus among treatment groups. There was no effect of the gestation diet or a gestation x lactation diet interaction on any parameter measured. On d 7 of lactation, plasma concentrations of Arg and insulin in sows, as well as concentrations of most AA in milk, were greater (P < 0.05) in response to Arg supplementation during lactation compared with the control. Weight gain of piglets from sows fed the Arg-supplemented diet during lactation was greater between d 0 and 7 (P < 0.01) and between d 0 and 21 (P < 0.05) of lactation compared with piglets from sows fed the control diet. Collectively, results from this study indicate the potential beneficial effects of dietary Arg supplementation in improving the lactation performance of first-parity sows.     

Effects of nutrient supply, plasma metabolites, and nutritional status of sows during transition on performance in the next lactation

The aim of the present study was to evaluate the effects of nutrient supply, plasma metabolites, and nutritional status of sows during the transition from gestation to lactation on performance of piglets during the colostral period and throughout lactation. Forty second-parity sows were fed 1 of 4 gestation diets containing a different quantity of dietary fiber (171 to 404 g/kg of DM) from mating until d 108 of gestation. From d 108 of gestation until weaning (d 28 of lactation), sows were fed 1 of 5 lactation diets with a different quantity of dietary fat [3 or 8% with different proportions of medium- (MCFA) and long-chain fatty acids (LCFA)]. Blood was obtained by jugular venipuncture on d 108 and 112 of gestation and on d 1 of lactation, and concentrations of plasma glucose, NEFA, lactate, acetate, propionate, butyrate, and fatty acids were analyzed. Piglet growth and mortality were noted throughout lactation. Piglet mortality during the colostral period (0 to 24 h) was affected by the lactation diets and was positively related to sow backfat (d 108) and plasma lactate (d 112) and negatively related to mean piglet birth weight (P < 0.05). Mean piglet live BW gain (LWG) was recorded in the periods 0 to 24 h, 7 to 10 d, 14 to 17 d, and 17 to 28 d relative to parturition as indirect measures of colostrum yield (0 to 24 h), milk yield in early lactation (d 7 to 10), and at peak lactation (d 14 to 17 and d 17 to 28). Effects of gestation and lactation diets on studied sow traits were tested on selected days during the transition period and the next lactation, and tested statistically on separate days. The LWG in the colostral period was positively correlated with mean piglet birth weight (P < 0.001), plasma concentrations of propionate and MCFA (P < 0.05), and plasma acetate and butyrate (P < 0.1) on d 1 of lactation. The LWG in early lactation was inversely correlated with plasma lactate on d 108 (P < 0.05), plasma glucose on d 112, and backfat thickness on d 108 (P < 0.10). The LWG at peak lactation was positively correlated with MCFA intake of the sow on d 113 to 115 and backfat thickness on d 108 during the transition, and negatively correlated with intake of LCFA and ME intake on d 108 to 112 (P < 0.05). In conclusion, feeding and body condition of sows during the transition from gestation to lactation is important for neonatal piglet survival, lactation performance of sows, and piglet growth during the next lactation.     

Reproductive performance of sows supplemented with dietary L-carnitine over three reproductive cycles.

The effect of L-carnitine supplementation during pregnancy and lactation on the reproductive performance of sows was studied in two separate trials over three reproductive cycles. Both trials were identical in design and conduct but were performed with different animals. The trials comprised of a total of 127 sows (trial 1) and 100 sows (trial 2) which were divided into control and treatment groups. All animals were fed individually and received basic feed mixtures with low native carnitine concentrations. The rations of the sows in the treated group were supplemented with 125 mg L-carnitine per head and day during pregnancy and 250 mg L-carnitine per head and day during lactation. The animals of the control group received identical feed mixtures in identical amounts, but without the L-carnitine supplement. In the first trial, 212 litters were produced and evaluated for number and body weight of the animals, in the second trial, 173 litters were produced. L-carnitine supplementation significantly increased body weight gains of the sows between day 1 and day 85 of weaning. The number of born piglets, stillborn piglets and piglets fit for rearing was not influenced by dietary L-carnitine supplementation. However, L-carnitine supplementation significantly increased the weights of piglets and litters at birth, weight gains of litters during suckling and weights of litters at weaning. These effects of L-carnitine were seen in both trials; they were independent of the age of the sows and remained over three reproductive cycles in which the sows where continuously treated with L-carnitine. Overall, the study shows that dietary supplementation with L-carnitine during pregnancy and lactation improves the reproductive performance of sows over several reproductive cycles, independent of the age of the sows.     

Some Factors Influencing Pregnancy Rate and Subsequent Litter Size in Primiparous Sows

The pregnancy rate and the subsequent litter size were studied in 332 Swedish Yorkshire primiparous sows, fed according to a commercial Swedish feeding regime during lactation. The sows were weighed and backfat depth was recorded at the first farrowing, at weaning, and at mating. Oestrous detection was performed once daily after weaning, and the interval from weaning to first oestrus (IWO) was recorded. Blood samples for determination of plasma progesterone were drawn regularly after the first weaning. Statistical analyses were only performed on sows with an IWO of 3-8 days. Of these 206 sows were mated on their first (OE1 sows) and 87 sows on their second (87 OE2 sows) oestrus after weaning.The pregnancy rate was 85.4% for OE1 sows and 75.9% for OE2 sows (p=0.048). There was no significant difference in pregnancy rate between OE1 sows with an IWO of 3-5 days and OE1 sows with an interval of 6-8 days. OE2 sows with an IWO of 6-8 days, on the other hand, had a significantly lower pregnancy rate compared with OE2 sows with an interval of 3-5 days. The pregnancy rate in sows that lost more than 30 kg during the first lactation period did not differ from that of sows losing less than 30 kg. In sows with a first litter size of more than 9 piglets alive at birth, the pregnancy rate decreases significantly if mating is delayed until the second oestrus after weaning.OE2 sows had a significantly larger second litter size at birth than OE1 sows (+ 2.0). The litter size at six weeks did not, on the other hand, differ significantly (+ 0.4). There was a positive correlation between the IWO and 2nd litter size, although significant only for OE1 sows between the IWO and litter size alive at birth. In the OE1 group, sows losing 20 kg or less during lactation had significantly larger second litters at birth than the sows losing 21-30 kg, but not significantly larger than the sows losing more than 30 kg. One piglet more, at birth, in the first litter resulted in 0.25 piglet more in the second litter. For sows with a large first litter there was a low probability of also having a large second litter.     

Effects of supplementing Saccharomyces cerevisiae fermentation product in sow diets on performance of sows and nursing piglets

Forty-two sows were used to determine the effects of adding a Saccharomyces cerevisiae fermentation product (SCFP) to the gestation and lactation diets on the performance of sows and their progeny. At 5 d before breeding, sows were allotted to 2 dietary treatments representing 1) sows fed a diet with 12.0 g of fermentation product/d through gestation and 15.0 g of fermentation product/d through lactation (SCFP treatment, n=22), and 2) sows fed a diet with equal amounts of a mixture of corn and soybean meal instead of the SCFP (CON treatment, n=20). Sow BW and backfat thickness were recorded. Blood was collected from sows, as well as piglets, for the measurement of cell numbers, plasma urea nitrogen (PUN), and IgG. Fecal samples from d 7 to 9 of lactation were collected to determine apparent total tract nutrient digestibility. The composition of colostrum and milk was also measured. No difference (P > 0.10) in reproductive performance was observed between treatments. However, sows in the SCFP treatment tended to have increased total litter weaning weight (P=0.068) and litter BW gain (P=0.084) compared with sows in the CON treatment. Neutrophil count was decreased (P < 0.05) by adding the fermentation product on d 110 of gestation and d 17 of lactation, whereas a decreased (P < 0.05) white blood cell count was observed only on d 110 of gestation. Concentration of PUN tended to be greater (P=0.069) for sows in the CON treatment compared with sows in the SCFP treatment on d 110 of gestation. Apparent total tract nutrient digestibility values of ash, CP, DM, and ether extract were not affected (P > 0.10) by adding the fermentation product. Protein and fat contents in colostrum and milk did not differ (P > 0.10) between treatments. Colostrum from sows in the SCFP treatment contained a greater (P < 0.05) amount of ash than colostrum from sows in the CON treatment. Immunoglobulin G measured in the colostrum, milk, and plasma of piglets did not differ (P > 0.10) between sows in the CON and SCFP treatments. This study indicates that adding the SCFP in the gestation and lactation diets has the potential to 1) improve litter BW gain during lactation, possibly by improving maternal protein utilization, as shown in a tendency to reduce PUN; 2) improve the maternal health status, as shown by the reduced neutrophil cell count; and 3) increase milk production, as shown in a tendency to improve litter BW gain without affecting nutrient composition of the colostrum and milk.     

Effects of dietary star anise (Illicium verum Hook f) supplementation during gestation and lactation on the performance of lactating multiparous sows and nursing piglets

Thirty‐two sows were allocated to four treatments to evaluate the effect of dietary star anise (SA) supplementation during gestation and lactation on the lactational performance of sows. At 85 days of gestation, sows were randomly allotted to one of two diets supplemented with 0.5% SA or basal diet. After farrowing, sows were further allotted to one of two lactation diets supplemented with 0.5% SA or basal diet. On a weekly basis, body weight (BW) of sows and piglets was measured. Blood and milk samples were obtained from the sows and piglets. Number of days from weaning to estrus, milk yield and feed intake were also recorded. Weight gain of piglets from sows fed the SA‐supplemented diet during lactation was greater between days 7 and 14, days 14 and 21 and the overall experimental period compared with control groups. Supplementation of SA during lactation improved weaning weight of piglets, milk yield and average daily feed intake (ADFI) of sows. The SA diet increased concentrations of insulin‐like growth factor‐1 (IGF‐1) in ordinary milk and prolactin (PRL) in serum of sows. In conclusion, this study has indicated the beneficial effects of dietary SA addition in improving the lactation performance of sows.     

Reproductive failure associated with porcine parvovirus in an enzootically infected pig herd.

Two outbreaks of porcine parvovirus occurred in a unit of 380 sows, with a subsequent decrease in the size of gilts' litters. Of the 203 gilts and 64 primiparous sows which were seronegative at the time of insemination, 134 gilts and 55 primiparous sows seroconverted during pregnancy. Of the second parity sows nine of 271 were still seronegative at the time of insemination but all nine seroconverted during their third gestation. The gilts that seroconverted during their first pregnancy produced on average 0.9 fewer live piglets than the gilts that did not seroconvert. Second litter sows which seroconverted produced 0.3 fewer piglets than those which did not seroconvert. There were no significant differences between sows which seroconverted or did not seroconvert in the numbers of returns to service, or in the percentages of piglets which were born dead or died before weaning.     

Dietary fiber for pregnant sows: influence on sow physiology and performance during lactation

This study was conducted to investigate the effects of feeding sows a bulky diet during gestation on their physiological and metabolic adaptations during the peripartum period, and to determine how these effects may relate to sow and piglet performances. From d 26 of gestation until farrowing, gilts were fed diets that contained 2.8 or 11.0% crude fiber (control and high-fiber diets, respectively, n = 9/group). Daily feed allowance provided the same amount of DE daily (33 MJ of DE/d). Throughout lactation, sows were allowed to consume a standard lactating sow diet ad libitum. Litters were standardized to 12 piglets beyond 48 h after birth. On d 105 of gestation, a jugular catheter was surgically implanted. Preprandial blood samples were collected from d 109 of gestation to the day after farrowing and on d 4, 18, and 26 of lactation. Meal tests and glucose tolerance tests were performed on d 109 of gestation and d 4 and 18 of lactation. During gestation, BW and backfat gain did not differ between treatment groups. During lactation, sows fed the high-fiber diet ate an average of 0.94 kg/d more than control sows (P < 0.02). Piglets born from sows fed the high-fiber diet grew faster than piglets from control sows (P = 0.03). Body weight and backfat losses did not differ between the 2 treatment groups. Sows fed the high-fiber diet during gestation had lesser concentrations of leptin before farrowing than control sows (P < 0.01). Leptin concentrations were negatively correlated with feed intake during lactation (P < 0.05). The prepartal increase in prolactin concentrations tended to be greater in sows fed the high-fiber diet than in control sows (P < 0.1). Preprandial concentrations of glucose, NEFA, lactate, and IGF-I fluctuated over time without significant treatment effect. Glucose half-life was shorter in late gestation than during both stages of lactation, but did not differ between sows in the 2 groups. In late gestation, the postprandial increases in glucose and insulin were delayed, and smaller, after a high-fiber meal than after a control meal. During lactation, glucose and insulin profiles after a standard meal did not differ between sows from treatment groups. In conclusion, the greater appetite of lactating sows fed a high-fiber diet during gestation does not seem related to changes in glucose and insulin metabolism and may be partly due to decreased secretion of leptin. The greater feed consumption was accompanied by a faster growth rate of piglets without sparing effect on maternal body reserves.     

羟甲基丁酸钙盐对妊娠后期-哺乳期母猪繁殖性能、乳成分及仔猪生长性能的影响

文章旨在评估日粮中添加羟甲基丁酸钙盐对妊娠后期到哺乳期母猪繁殖性能、乳成分及仔猪生长性能的影响.试验选择32头胎次接近的二元母猪,随机分为2组,每组4个重复,每个重复4头猪.对照组母猪在妊娠后期和哺乳期饲喂基础日粮,处理组母猪在妊娠和哺乳期饲喂基础日粮+8?mg/kg羟甲基丁酸钙,试验从分娩前6?d到仔猪21?d断奶....     

Effects of concentrations of cyanocobalamin in the gestation diet on some criteria of vitamin B12 metabolism in first-parity sows

In swine nutrition, little is known about the role of vitamin B(12) in the reproductive processes. The current study was undertaken to obtain information on the dose-response pattern of different metabolic criteria related to the homeostasis of vitamin B(12) and homocysteine in gestating sows receiving various concentrations of dietary vitamin B(12) (cyanocobalamin). Homocysteine is a detrimental intermediate metabolite of the vitamin B(12)-dependent remethylation pathway of Met. Forty nulliparous (Large White x Landrace) sows were randomly assigned during gestation to dietary treatments containing 5 concentrations of cyanocobalamin (0, 20, 100, 200, or 400 microg/kg). During lactation, a diet containing 25 microg of cyanocobalamin/kg (as-fed) was given to all sows. During gestation, plasma vitamin B(12) increased as concentrations of dietary cyanocobalamin increased (linear and quadratic, P < 0.01) and the effect persisted during lactation (21 d postpartum) both in plasma (linear and quadratic, P < 0.05) and the liver (linear and quadratic, P < 0.04). Plasma homocysteine decreased with concentrations of cyanocobalamin provided to sows during gestation (linear, quadratic, and cubic, P < 0.01). At parturition, vitamin B(12) in colostrum increased as concentrations of cyanocobalamin increased (linear and quadratic, P < 0.01), but the treatment effect persisted (linear, P = 0.01) only up to 1 d postfarrowing. However, in piglets there was no treatment effect (P = 0.59) on plasma vitamin B(12) before colostrum intake, but a linear effect of concentrations of cyanocobalamin (P = 0.04) was observed 1 d later. Plasma homocysteine in piglets during lactation decreased with increasing concentrations of cyanocobalamin given to sows in gestation (linear and quadratic, P < 0.01). Based on a broken-line regression model, the concentrations of dietary cyanocobalamin that maximized plasma vitamin B(12) and minimized plasma homocysteine of sows during gestation were estimated to be 164 and 93 microg/kg, respectively. The maximal residual responses in sows and piglets during lactation were observed with treatments of 100 or 200 microg of cyanocobalamin/kg. The dietary cyanocobalamin concentration necessary to optimize the response of these metabolic criteria remains to be refined within lower and narrower ranges of cyanocobalamin concentrations (i.e., <200 mg/kg). Moreover, the biological significance of such concentrations of cyanocobalamin needs to be validated with performance criteria by using greater numbers of animals during several parities.     

Effects of magnesium on the performance of sows and their piglets

The objective of this study was to evaluate the effects of supplemental magnesium(Mg) on the performance of gilts and parity 3 sows and their piglets.Fifty-six gilts(Trial 1) and 56 sows(Trial 2) were assigned to one of 4treatments according to their mating weight,respectively.The treatments comprised corn-soybean meal based gestation and lactation diets(0.21%magnesium) supplemented with 0,0.015,0.03,or 0.045%Mg from mating until weaning.The results showed that magnesium supplementation significantly(P 0.05) reduced the weaning to estrus interval in both gilts and sows.There were significant effects(P 0.05) of supplemental magnesium on the total number of piglets born,born alive and weaned in sows.In late gestation and lactation,the digestibility of crude fiber(quadratic effects,P 0.05),and crude protein(P 0.05),were significantly influenced by magnesium in gilts and sows,respectively.There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows(P 0.05) during both early and late gestation.The apparent digestibility of gross energy was increased for sows in late gestation(P 0.05),and lactation(quadratic effects,P 0.05).At farrowing and weaning,serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased(P 0.05).Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation(P 0.05).The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium(P 0.05).In addition,growth hormone levels were linearly elevated(P 0.05) in the serum of piglets suckling sows.Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows,and the suitable supplemental dose ranged from 0.015%to 0.03%.