Effects of different gestation housing types on reproductive performance of sows

This study evaluated the effects of different gestation housing types on reproductive performance of sows. A total of 60 sows (218 ± 24 kg body weight) with mixed parity were used. During gestation, 28 sows were housed in groups with electronic sow feeders (space allowance = 1.26 m²/sow) and 32 sows were housed in individual stalls (space allowance = 1.20 m²/sow). Sows from both housing types were moved to farrowing crates on day 109 of gestation and stayed until weaning (18 days post‐farrowing). Typical corn‐soybean meal diets were provided to sows during gestation and lactation. Measurements were reproductive performance of sows at farrowing as well as performance of sows and their litter during lactation. Similar total numbers of piglets born at farrowing were observed for sows gestated in both housing types. However, group‐housed gestation sows had more mummies (0.321 vs. 0.064; P < 0.05) and stillbirths (0.893 vs. 0.469; P = 0.073) at farrowing than individual‐housed gestation sows. Consequently, individual‐housing type had higher percentage of piglets born alive (95.5 vs. 90.4%; P < 0.05) than the group‐housing type. Therefore, improved reproductive performance of sows from individual gestating housing was confirmed in this study.     

Effects of 25‐hydroxycholecalciferol supplementation in maternal diets on milk quality and serum bone status markers of sows and bone quality of piglets

Twenty primiparous sows were allocated to two treatments to evaluate the effects of maternal 25‐hydroxycholecalciferol (25OHD₃) supplementation during gestation and lactation on milk quality and serum bone status markers of sows and bone quality of piglets. Immediately after mating, sows were randomly allotted to one of two diets supplemented with 50 µg/kg 25OHD₃ or basal diets without 25OHD₃. Blood and milk samples were obtained. At birth and weaning, 10 piglets from each treatment were killed for bone quality analysis. 25OHD₃‐fed sows provided one more piglet at farrowing and 1.17 more piglets at weaning than sows fed basal diets. The contents of solids not‐fat, protein, fat or lactose were increased in milk from days 7 and 14 of lactation in 25OHD₃‐supplemented sows and 25OHD₃ concentrations in milk were increased by dietary 25OHD₃ supplementation. Dietary 25OHD₃ supplementation increased serum alkaline phosphatase activity but had no effect on serum tartrate‐resistant acid phosphatase activity of sows. Maternal 25OHD₃ supplementation improved bone strength, density and ash content of newborn piglets rather than those of weaning piglets. In conclusion, 25OHD₃ supplementation in maternal diets improved reproductive performance, milk quality and bone status of sows as well as bone quality of newborn piglets.     

ORIGINAL ARTICLE: Impact of inulin and a multispecies probiotic formulation on performance,microbial ecology and concomitant fermentation patterns in newly weaned piglets

The effect of inulin and a multispecies probiotic formulation on performance and microbial parameters in a 28 days feeding trial with newly weaned piglets was assessed. Forty‐eight piglets were allocated to a 2 × 2 factorial experiment involving two levels of inulin supplementation (0% or 0.4%) and two levels of probiotics (0 or 1 × 10⁹ CFU/kg as fed, comprising enterococci, lactobacilli and bifidobacteria). In digesta samples obtained at slaughter (stomach, jejunum, ileum and colon), selected bacterial groups were enumerated and lactic acid, short chain fatty acids and ammonia concentrations analysed. The overall performance of piglets was unaffected by treatment. Inulin increased total aerobes in stomach and jejunum (p < 0.05), whereas enterococci declined in colon of the inulin group (p < 0.05). Furthermore decreasing colonic acetic acid (p < 0.01) and increasing lactic acid (p < 0.05) was observed for inulin. Probiotics increased total aerobes (p < 0.05) and enterococci (p < 0.01) in ileum and lactobacilli (p < 0.05), enterococci and gram‐negative anaerobes (p < 0.01) in colon. Moreover, dry matter content in stomach and colon was lower and acetic acid in colon increased (p < 0.05). A decrease in ileal pH value was noted symbiotically for both additives. However, several parameters showed no synbiotic, but distinct individual effects of inulin and probiotics. Effects occurred along the entire gastrointestinal tract without restriction to the colon.     

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.     

Sow performance and maternal behaviour in organic and conventional herds

Abstract

The study evaluates the first three parities of 144 Swedish Landrace×Yorkshire sows from three certified organic and three conventional commercial piglet-producing herds. Sows and litters were weaned at seven and five weeks post partum (pp) in organic and conventional herds, respectively. Herdsmen judged sow behaviour and maternal ability at farrowing, two weeks pp and at weaning. Herdsmen collected registrations of litter size, litter weight and sow fat status at farrowing and at weaning. Piglet mortality and oestrous signs were registered continuously during the nursing period. Sows in organic herds were scored to be more cautious among piglets, and to have better nursing behaviour and maternal ability in early lactation than sows in conventional herds. Piglet mortality was higher in organic than in conventional herds. Oestrus during lactation was only observed among sows in organic herds, and sows showing oestrus during lactation were fatter at weaning.     

Effects of L‐citrulline supplementation on heat stress physiology,lactation performance and subsequent reproductive performance of sows in summer

Lactating sows are susceptible to heat stress (HS). Part of the thermoregulatory response to HS is to increase peripheral blood flow, which is mediated in part by the vasodilator, nitric oxide (NO). Therefore, the aim of this experiment was to determine the effect of supplementation of L‐citrulline, a NO precursor, on symptoms of HS, lactation performance and subsequent reproductive performance of sows in summer. A total of 221 summer farrowing mixed parity sows were fed either a control diet or supplemented with 1% L‐citrulline upon entry to the farrowing house (6 ± 1.8 days for mean ± standard deviation [SD] before farrowing) until weaning (26 ± 1.5 days). The average daily minimum and maximum temperature in the farrowing house was 21.0 ± 1.88 and 29.2 ± 3.82°C (mean ± SD). Rectal temperature, respiration rate, and plasma and urinary nitrite and nitrate (NOx) of sows were measured on the 19th day post‐farrowing. Supplemental L‐citrulline in the diet did not affect the number of piglets born alive, feed intake of sows, body weight or backfat thickness of sows at weaning, or litter weight gain. L‐citrulline tended to reduce piglet pre‐weaning mortality rate from 18.6% to 15.6% (p = 0.058). L‐citrulline reduced the respiration rate of sows compared to the control diet at 17:00 hr (Time × Diet, p < 0.001); however, rectal temperature was not affected. L‐citrulline tended to increase urinary NOx concentrations (127 vs. 224 µM, p = 0.057) but not plasma NOx concentrations. L‐citrulline did not affect farrowing rate or number of piglets born alive in the subsequent parity. In conclusion, L‐citrulline supplementation reduced respiration rate of lactating sows and reduced piglet pre‐weaning mortality rate in summer. Whether the effects were due to a NO‐dependent mechanism requires further validation.     

Elevating glucose and insulin secretion by carbohydrate formulation diets in late lactation to improve post‐weaning fertility in primiparous sows

Primiparous (P1) sows commonly lose excessive body reserves to meet energy requirements for maintenance and milk production during lactation, and consequently, post‐weaning reproductive performance may be compromised. The present studies determined whether ad libitum feeding a glucogenic carbohydrate diet (CHO) during late lactation could stimulate insulin and glucose secretion (experiment 1) and improve subsequent litter size (experiment 2). For experiment 1, 15 P1 sows, and for experiment 2, 99 P1 sows (198.5 ± 2.7 kg) were allocated randomly according to suckled litter size (≥10 piglets), either to a CHO diet (14.3 MJ DE/kg, 19.8% crude protein) or a standard lactation diet (control; 14.2 DE MJ/kg, 19.5% crude protein) at 8 days before weaning. The CHO diet aimed to provide glucogenic content (extruded wheat, dextrose and sugar) as energy sources instead of fat sources without changing total dietary energy. Pre‐prandial plasma glucose and insulin concentrations were not influenced by treatments. However, post‐prandial plasma glucose and insulin concentrations and their peaks were both higher (p < .05) compared to the control treatment. Body weight loss during lactation was relatively low at 3%–4% for both treatments and did not differ between control and CHO treatments (?7.6 ± 1.6 vs ?5.4 ± 1.2 kg; p > .05). Second litter size was not influenced by diet (p > .05), but the weaning‐to‐mating interval was shorter in CHO sows (p < .05). This study demonstrates that providing an enriched CHO diet in late lactation did influence post‐weaning follicle growth but did not improve subsequent litter size. This may be due to the primiparous sows in this study not experiencing severe negative energy balance and there was no second litter syndrome in this farm which limited the ability of diet to improve sow fertility.     

Season-dependent effect of daily frequency of feed distribution on the rate of feed consumption and reproductive performance in sows during lactation

The effects of the daily frequency of feed distribution (once, One; twice, Two; and four times, Four,) on the rate of feed consumption (RFC) and reproductive performance were investigated in Large White sows farrowing in the hot season from June to September (H sows) and in the rest of the year (R sows). The RFC was greater in feeding treatment Four than Two (P < 0.01) in H sows; however, bodyweight loss during lactation was not affected by the feeding treatment. No difference in effects of frequency of feed distribution for sows was observed on piglet growth. The survival rate of the piglets was not different between feeding treatments. The number of sows that came into estrus within 7 days post‐weaning was smaller in the feeding treatment Four than One (P < 0.05) in H sows and those of Four than One (P < 0.01) and Two (P < 0.05) in R sows. These results suggest that in sows during lactation increasing the daily frequency of feed distribution may have a negative effect on reproductive performance.     

Protection Against Neonatal Escherichia coli Diarrhoea in Pigs by Vaccination of Sows with a New Vaccine that Contains Purified Enterotoxic E. coli Virulence Factors F4ac,F4ab,F5 and F6 Fimbrial Antigens and Heat‐Labile E. coli Enterotoxin (LT) Toxoid

The efficacy of a new vaccine against neonatal Escherichia coli diarrhoea in piglets containing purified F4ab, F4ac, F5 and F6 fimbriae and detoxified heat‐labile toxin (LT) was tested in challenge experiments by the method described by the European Pharmacopoeia (3rd edn, EDQM, Council of Europe, Strasbourg, France). A group of 11 young sows from a herd without E. coli problems was vaccinated 6–8 and 2–4 weeks prior to expected farrowing and another group of nine young sows were non‐vaccinated controls. Escherichia coli antibody titres were determined in serum samples taken from the sows before first vaccination and before farrowing and in colostrum samples. The newborn piglets were allowed to suckle colostrum from their mother immediately after birth. The piglets were marked with individually numbered ear tags. Approximately 12 h after birth, 118 piglets from vaccinated sows and 79 piglets from non‐vaccinated control sows were challenged by oral instillation of 5 ml of a freshly prepared culture of one of the challenge strains [O8:K87:F4ab (LT+) or O149:K91:F4ac (LT+) or O9:K30:F5 or O9:K103:F6 respectively]. The challenge cultures contained as a mean 6.8 × 10⁹ CFU/ml. After challenge the piglets were observed for 7 days and mortality and morbidity were recorded. Vaccinated sows developed significant levels of antibody titres in colostrum and serum. Control sows stayed at a low/seronegative level. The protective efficacy was excellent because 66.7–87.5% of the piglets from vaccinated sows remained without clinical signs after challenge. Only 0.0–28.0% of the piglets from non‐vaccinated sows remained healthy and more than 47.1% of the piglets in this group died after challenge. It is concluded that the new vaccine is very effective in protection of piglets against neonatal E. coli diarrhoea.     

Evaluation of three different patterns of feed intake during early lactation in lactating sows

Forty‐five multiparous sows (Landrace × Yorkshire; parity: 3.58 ± 1.30) were used to determine the effects of three patterns of feed intake during early lactation on the performance of lactating sows. Experimental treatments were as follows: IFI‐1.4, the amount of feed increased by 1.4 kg per day for the first 5 days post‐farrowing, followed by ad libitum feeding until weaning; IFI‐1.0, the amount of feed increased by 1.0 kg per day for the first 7 days post‐farrowing, followed by ad libitum feeding until weaning; IFI‐0.7, the amount of feed increased by 0.7 kg per day for the first 10 days post‐farrowing, followed by ad libitum feeding until weaning. The number of live piglets at birth/litter in three dietary treatments was 11.50, 10.07, and 10.85, respectively. Sows in the IFI‐1.4 treatment had lower backfat loss during lactation, greater daily feed intake during days 1–6, 7–12, and 1–24 compared with those in the IFI‐0.7 treatment (p < .05). The litter weaning weight, litter weight gain, and average litter daily gain in the IFI‐1.4 treatment were greater compared with those in the IFI‐0.7 treatment (p < .05). In conclusion, the results indicated that the IFI‐1.4 feed intake pattern allowed lactating sows and their litters to obtain optimal performance.     

Effects of cellulase supplementation to corn soybean meal‐based diet on the performance of sows and their piglets

A total of 15 primiparous sows (Landrace × Yorkshire) and their litters were used in the current study to evaluate the efficacy of cellulase supplementation on the production performance of sows and piglets. Pigs were randomly allocated into one of three treatments with five replicates per treatment. The dietary treatments were as follows: (i) CON (corn‐soybean meal‐based control); (ii) EZ1 (CON + 0.05% cellulase); and (iii) EZ2 (CON + 0.10% cellulase). The supplementation of cellulase had no effect (P > 0.05) on body weight and feed intake of lactating sows. At weaning, back fat thickness loss decreased (P = 0.04) linearly in EZ1 and EZ2 treatments. The average daily gain (ADG) of piglets increased (linear P = 0.06, quadratic P = 0.04)) during days 14 to 21 as well as at days 21 to 25 (linear P = 0.03 and quadratic P = 0.01) with the increase in the level of supplemented enzyme. Dry matter and nitrogen digestibility increased (linear P = 0.01) in lactating sows fed EZ1 and EZ2 diet compared with CON. In conclusion, it is suggested that cellulase supplementation to corn‐soybean meal based diet exerts beneficial effects to sows in reducing their back fat thickness loss at weaning and also helps to improve nutrient digestibility. It also helped to improve the ADG of piglets.     

The Post‐Cervical Insemination does not Impair the Reproductive Performance of Primiparous Sows

The study evaluated the reproductive performance of primiparous sows submitted to post‐cervical insemination (PCAI) compared with cervical artificial insemination (CAI). Difficulty with catheter introduction, the occurrence of bleeding or semen backflow during insemination, and volume and sperm cell backflow up to 60 min after insemination were also evaluated. Sows were homogenously distributed, according to body weight loss in lactation, lactation length, weaned piglets, weaning‐to‐oestrus interval and total born in previous farrowing, in two treatments: PCAI (n = 165) with 1.5 × 10⁹ sperm cells in 45 ml (2.4 ± 0.04 doses per sow) and CAI (n = 165) with 3 × 10⁹ sperm cells in 90 ml (2.5 ± 0.04 doses per sow). During PCAI, sows were inseminated in the absence of boars. Transabdominal real‐time ultrasonography was performed at oestrus onset, immediately before the first insemination and at 24 h after last insemination. There was no difference (P > 0.05) between treatments in farrowing rate (91.5% × 89.1%) and litter size (12.5 × 11.9 piglets born, respectively for PCAI and CAI sows). Successful passage of the intrauterine catheter in all the inseminations was possible in 86.8% (165/190) of sows initially allocated to PCAI treatment. Difficulty of introducing the catheter in at least one insemination did not affect the reproductive performance of PCAI sows (P > 0.05). Bleeding during insemination did not affect (P > 0.05) the farrowing rate in both treatments, but litter size was reduced in CAI and PCAI sows (P ≤ 0.06). Percentage of spermatozoa present in backflow within 1 h after insemination was greater in CAI than PCAI sows (P < 0.01). More than 85% of primiparous sows can be successfully post‐cervical inseminated with doses containing 1.5 × 10⁹ sperm cells in the absence of the boar during insemination without impairing the reproductive performance.     

Lactation efficiency as a result of body composition dynamics and feed intake in sows

Through genetic selection and improvement of environment, litter size of sows increases. Increased energy requirement during lactation, increases the risk of excessive mobilization from body stores, with detrimental effects on reproductive performance. Feed intake capacity tends to decrease due to selection towards leaner pigs with a lower feed conversion ratio. However, to facilitate sows to wean large litters extra feed intake, or even better, a higher feed efficiency during lactation would be favourable. The objective of the present study was to describe the dynamics of body composition of sows and piglets during lactation, and to relate these traits to a newly introduced trait called “lactation efficiency”. Energy metabolism of lactating sows was described, based on on-farm observations of weight and backfat of sows before parturition and at weaning, weight of piglets at birth and at weaning and feed intake of sows during lactation. “Lactation efficiency” was defined as energy efficiency of sows, and calculated for individual sows at two different farms. The average lactation efficiency was 68% and 65% for both farms; meaning that 68 and 65% of the metabolisable energy through feed intake or mobilization from body stores, above maintenance of the sow (input), was used for piglet growth and piglet maintenance (output). The association between lactation efficiency and other reproductive traits was studied by estimating the correlations within farms. Sows with a higher lactation efficiency showed lower feed intake (r = − 0.27 and r = − 0.35 for both farms respectively) and smaller fat losses (r = − 0.34 and r = − 0.29, respectively). The energy output of efficient sows was slightly higher (r = 0.23 and r = 0.30). The more efficient sows were the better mothers, as mortality of their piglets was lower (r = − 0.12 and r = − 0.16), piglet growth rate was higher (r = 0.16 and r = 0.23), and at weaning their litters were less variable (r = − 0.08; only available at one farm). Results were remarkably similar for the two farms, despite different feeding strategies. Extra input, by means of feed intake or mobilization from body stores generated extra output by means of litter weight at weaning. This experiment demonstrated that an accurate recording of energy metabolism and relevant reproduction traits with little intervention is possible on commercial farms.     

Dietary linseed oil in the maternal diet affects immunoglobulins,tissue fatty acid composition and expression of lipid metabolism‐related genes in piglets

This experiment investigated the effects of supplementing the maternal diet with linseed oil (LSO) and soya bean oil (SBO) on immunoglobulins, the fatty acid composition and hepatic expression of lipid metabolism‐related genes in piglets. Multiparous sows (twenty‐four per diet) were fed on diets containing a supplement of either SBO or LSO during last week of gestation and lactation. The results indicated that supplementation of maternal diet with LSO could improve the weaning weight of piglets and average daily gain (ADG) (p < 0.05). The concentration of immunoglobulin G (IgG) and immunoglobulin A (IgA) was enhanced in sow plasma, colostrum and milk by the addition of LSO (p < 0.05). In addition, the concentration of 18: 3n‐3 fatty acids was higher in the milk of LSO sows. Meanwhile, maternal supplementation with LSO increased the levels of plasma IgG, IgA and the tissues n‐3 polyunsaturated fatty acid (PUFA) in piglets (p < 0.05). Correspondingly, the mRNA expression levels of hepatic ?5‐desaturase (D5D) and ?6‐desaturase (D6D) were higher, and fatty acid synthase (FAS) was lower in piglets from LSO‐fed sows when compared with that in the SBO group. In conclusion, LSO supplementation of the maternal diet increases immunoglobulins, modifies the fatty acid composition and affects the gene of D5D and D6D expression of piglets.     

Comparative effects of sodium butyrate and flavors on feed intake of lactating sows and growth performance of piglets

We examined the effects of sodium butyrate and flavors on feed intake of lactating sows and growth performance of piglets. A total of 52 primiparous sows (Large White) were randomly divided into four treatments (n = 13) and received 6 g/kg sodium butyrate (SB), fruit‐milk (FM) flavor and fruit‐milk‐anise (FMA) flavor with pair feeding to the mothers receiving the control diet. The feeding trial lasted for 29 days, including 21 days of nursing and 8 days of post‐weaning period, respectively. The nursing and weaning piglets received creep diets with the same flavor or SB supplement as their mother. The results showed that FMA flavor increased average daily feed intake (ADFI) of lactating sows (P < 0.01), as well as improved litter weight gain (P = 0.05) and ADFI (P < 0.01) of nursing pigs among treatments. Indeed, greater ADFI and average daily gain of weaning piglets for the initial 8 days after weaning was observed in the FMA group compared with those in the control group (P < 0.01). These findings indicated that adding FMA flavor was superior to SB for increasing feed intake of lactating sows and improving growth performance of piglets.     

Effect of ginseng polysaccharides on the immunity and growth of piglets by dietary supplementation during late pregnancy and lactating sows

There are many reports that dietary supplementation with plant polysaccharides in pigs might promote their growth, but little is known about the maternal effect of ginseng polysaccharides (GPS) on piglets’ growth by dietary supplementation to pregnant and lactating sows. In the current study, the effects of dietary supplementation with GPS on the immunity of sows and growth of their piglets were investigated. Results showed no significant difference among the four groups in the total number of piglets, live piglets, weak piglets and birth weight of piglets, indicating the GPS‐treatment has no adverse effect on reproduction. Furthermore, the weaning weight of the GPS‐treated groups was higher than that of control group (P < 0.05); among them, the addition of 200 mg/kg dose has the best effect. Interestingly, GPS increased the total immunoglobulin G concentration in milk and serum of sows (P < 0.05). The concentrations of interleukin (IL)‐2, IL‐6, tumor necrosis factor (TNF)‐α, and interferon‐γ in milk and serum of sows were also increased in the experimental groups relative to the control (P < 0.05). Meanwhile, maternal supplementation of GPS significantly increased IL‐2 and TNF‐α concentration in the piglets’ serum of the experimental groups relative to control (P < 0.05). GPS (200 mg/kg) significantly increased the glutathione peroxidase activity in milk and serum (P < 0.05), while the concentrations of malondialdehyde were significantly reduced (P < 0.05). The present results indicated that GPS supplementation during late pregnancy and lactation improved immunity‐related bio‐molecular levels in sow serum and milk, which may be further beneficial to piglet health and growth through biological transmission effects.     

Synbiotics suppress the release of lactate dehydrogenase,promote non‐specific immunity and integrity of jejunum mucosa in piglets

The aim of our experiment was to study how synbiotics are able to deal with the problems of post‐weaning piglets. Lactobacillus plantarum – Biocenol^TM LP96 (CCM 7512), Lactobacillus fermentum – Biocenol^TM LF99 (CCM 7514) and flaxseed (rich in n‐3 polyunsaturated fatty acids) were administered to 36 conventional piglets from a problematic breed with confirmed presence of enterotoxigenic Escherichia coli and Coronavirus. The experimental piglets were supplied with probiotic cheeses and crushed flax‐seed in the period starting 10 days before weaning and lasting up to 14 days post‐weaning. Piglets in the control group were supplied only control cheese. The impact of such additives on the release of lactate dehydrogenase (LDH; spectroscopic and electrophoretic assay), alteration of immunity (index of metabolic activity), jejunum histology (light microscopy), and health of conventional piglets from a problematic breed (monitoring of hematology, consistency and moisture of feces and body temperature) were examined. We found significant decrease in LDH leakage in the blood serum and tissue extracts, indicating better cell membrane integrity in the individual organs of animals. Probiotics and flaxseed applied together seem to be a good source of nutrients to improve the immune status and the integrity of jejunum mucosa during infection. © 2015 Japanese Society of Animal Science     

Immunization of Sows in an Integrated Pig‐breeding Herd using a Homologous Inactivated Salmonella Vaccine Decreases the Prevalence of Salmonella typhimurium Infection in the Offspring

The efficacy of a homologous vaccination in preventing infection of suckling piglets with Salmonella (S.) Typhimurium was evaluated after an immunization of pregnant sows using an inactivated herd‐specific S. Typhimurium vaccine. Twenty‐five pregnant sows were vaccinated three times antepartum. The efficiency of this vaccine regime was assessed by comparison with a control group of 37 sows and their suckling piglets, which were daily treated with enrofloxacin from day 14 antepartum until the day of weaning. From the first day of life until day 142 post‐partum, faecal samples of the piglets were collected and analysed for Salmonella shedding. In parallel, systemic antibody responses were monitored using a whole cell‐based isotype‐specific enzyme‐linked immunosorbent assay (ELISA). The bacteriological investigation showed marked effects of vaccination. Salmonella Typhimurium could not be detected in any of the faecal samples of the piglets from the vaccinated sows. In contrast, the piglets of the group with long‐time antibiotic treatment shed salmonellae rating to 47.4% of the animals. Furthermore, the offspring from vaccinated sows showed significantly decreased antibody activities of immunoglobulin (Ig)A and IgG. These bacteriological and serological results indicate a significantly lower Salmonella prevalence in piglets of the vaccinated group. As this study shows, the presented strategy of vaccination of pregnant sows with an inactivated Salmonella vaccine seems to be a suitable measure in decreasing Salmonella prevalence in offspring of infected sows.     

Evaluation of the heat‐killed and dried cell preparation of Enterococcus faecalis against villous atrophy in early‐weaned mice and pigs

Early weaning induces villous atrophy in the small intestine (SI) of piglets. Oral administration of live lactic acid bacteria (LAB) can improve villous shortening. In this study, we evaluated the oral administration of a heat‐killed and dried cell preparation of Enterococcus faecalis (a LAB) strain EC‐12 against villous atrophy in early‐weaned mice (Experiment 1) and pigs (Experiments 2 and 3). Twelve 16‐days‐old mice were divided into two groups in Experiment 1: gavage of EC‐12 (10 mg/kg body weight (BW)/day), or control. On day 21, SI was collected. Eighteen 21‐day‐old pigs were divided into two groups in Experiment 2: gavage of EC‐12 (10 mg/kg BW/day), or control. After 10 days, the villous height of jejunum was measured. Six 21‐day‐old pigs were divided into two groups in Experiment 3: the basal diet supplemented with EC‐12 at 0.05%‐fed group, or the basal diet‐fed group. After 10 days, the villous height of jejunum was measured. The villous heights in SI were significantly higher by EC‐12 administration in all experiments. EC‐12 successfully improved the villous atrophy in the early‐weaned mice and pigs when EC‐12 was administered orally.     

Analysis of Possible Influence of Conjugated Linoleic Acid on Growth Performance and Losses of Piglets

The aim of this work was to evaluate the effect of supplementing the feed ration for lactating sows with the conjugated linoleic acid (CLA) on the growth performance and losses of piglets from birth to weaning. The monitoring comprised 20 litters in control and 20 litters in experimental group of Czech Large White × Czech Landrace hybrid combination sows. The control group was given a standard feed mixture for lactating sows, and experimental group was fed with the feed mixture supplemented with 2% of CLA, from the day of farrowing to the weaning of piglets, that is for the time of 28 days. The results of the experiment indicate the significantly better parameters of the numbers of reared piglets in the experimental group and the related lower level of losses of piglets from birth to weaning (p < 0.01). However, the feed mixture for lactating sows enriched in conjugated linoleic acid had no significant effect on the growth performance of piglets from birth to weaning (p > 0.05). Sows in the experimental group showed earlier onset of post‐partal oestrus after weaning of piglets (p < 0.05). These findings demonstrate that the supplementation of diet for lactating sows with CLA can improve survival of piglets from birth to weaning and shortening of weaning‐to‐oestrous interval in sows.