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Dry-aging of beef comprises the storage of carcasses and (sub)primal cuts at a low temperature and relative humidity for a prolonged period, aiming to increase the sensory quality of meat. Limited data are available on the survival and potential growth of pathogens on the surface of beef during dry-aging. Therefore, this study evaluates the changes in Salmonella, Shiga toxin-producing Escherichia coli O157:H7 and Listeria monocytogenes counts during dry-aging. A mixture of pathogenic strains was inoculated on the surface of beef loins, which were stored under four different process conditions (2 degrees C and 6 degrees C x relative humidity 75 and 85% during 42 days). Salmonella and E. coli O157:H7 counts significantly decreased during dry-aging. The daily reductions varied from -0.07 to -0.14 log(10) CFU and from -0.09 to -0.14 log(10) CFU, respectively, depending on the loin, matrix and condition. The reduction of L. monocytogenes was slower, with a maximum of -0.07 log(10) CFU/day. L. monocytogenes counts increased with 1.0 log(10) CFU on the lean meat of one loin with pH > 6.0 at the end of dry-aging, indicating that this pathogen can potentially grow under certain dry-aging conditions.

It was hypothesized that dietary guanidinoacetic acid (GAA), the precursor of creatine (Cr), would be beneficial to heat-stressed finisher broilers owing to improved cellular energy status and arginine sparing effects. A total of 720 one-day-old male Ross 308 broilers were allocated to 3 treatments, 0 (control), 0.6, or 1.2 g/kg of GAA added to complete corn–soybean meal diets, and were fed for 39 D, with 12 replicates (20 birds each) per treatment. A chronic cyclic heat stress model (at a temperature of 34°C and 50 to 60% relative humidity for 7 h daily) was applied in the finisher phase (day 25–39). Samples were taken on day 26 and 39 to determine thrombocyte, white blood cell, corticosterone, protein and amino acid levels in blood and Cr, phosphocreatine (PCr), and adenosine triphosphate levels in the breast muscle. Meat quality was assessed on day 40 after overnight fasting. Guanidinoacetic acid at a dose of 1.2 g/kg decreased feed-to-gain ratio compared with the control in the grower phase (1.32 vs. 1.35, respectively; P

Immunocastraten worden minstens vier weken vóór de slacht gevaccineerd om berengeur effectief te reduceren en de vleeskwaliteit te verbeteren ten opzichte van intacte beren. Uit een onderzoek van ILVO en UGent (LANUPRO) blijkt dat het toepassen van de tweede injectie (op acht of zes weken vóór de slacht) echter niet helpt om de vleeskwaliteit verder te verbeteren. Het blijkt zelfs economisch minder voordelig te zijn voor de varkenshouder aangezien de vroeg-gevaccineerde immunocastraten een hogere voederconversie en lagere slachtkwaliteit hebben.

In order to expand with validated scientific data the limited knowledge regarding the potential application of insects as innovative feed ingredients for poultry, the present study tested a partial substitution of soya bean meal and soya bean oil with defatted black soldier fly (Hermetia illucens) larvae meal (H) in the diet for growing broiler quails (Coturnix coturnix japonica) on growth performance, mortality, nutrients apparent digestibility, microbiological composition of excreta, feed choice, carcass and meat traits. With this purpose, a total of 450 10-day-old birds were allocated to 15 cages (30 birds/cage) and received three dietary treatments: a Control diet (C) and two diets (H1 and H2) corresponding to 10% and 15% H inclusion levels, respectively (H substituted 28.4% soya bean oil and 16.1% soya bean meal for H1, and 100% soya bean oil and 24.8% soya bean meal for H2, respectively). At 28 days of age, quails were slaughtered, carcasses were weighed, breast muscles were then excised from 50 quails/treatment, weighed, and ultimate pH (pHu) and L*, a*, b* colour values were measured. Breast muscles were then cooked to assess cooking loss and meat toughness. For the digestibility trial, a total of 15 28-day-old quails were assigned to the three feeding groups. The excreta samples were subjected to chemical and microbiological analysis. The same 15 quails were then simultaneously provided with C and H2 diets for a 10-day feed choice trial. Productive performance, mortality and carcass traits were in line with commercial standards and similar in all experimental groups. With the exception of ether extract digestibility, which was lower in H1 group compared with C and H2 (P=0.0001), apparent digestibility of dry matter, CP, starch and energy did not differ among treatments. Microbial composition of excreta was also comparable among the three groups. Feed choice trial showed that quails did not express a preference toward C or H2 diets. Breast meat weight and yield did not differ among C, H1 and H2 quails. Differently, the inclusion of H meal reduced meat pHu compared with C. In conclusion, this study demonstrated that H. illucens larvae meal can partially replace conventional soya bean meal and soya bean oil in the diet for growing broiler quails, thus confirming to be a promising insect protein source for the feed industry. Further research to assess the impact of H meal on intestinal morphology as well as on meat quality and sensory profile would be of utmost importance.

This study builds on the results of a previous study in which six commercial feed products based on organic acids were evaluated with respect to Salmonella contamination of piglets in an artificially challenged seeder model. In the present study, the efficacy of three of these commercial products was assessed for Salmonella reduction in fattening pigs on one closed farm with a natural high Salmonella prevalence. In each of four fattening compartments, one of the following feed treatments was evaluated during two consecutive fattening rounds: (i) butyric acid (active ingredients at 1.3 kg/ton of feed; supplement A1), (ii) a combination of short-chain organic acids (mixture of free acids and salts) and natural extracts (2.92 kg/ton; supplement A4), (iii) a 1:1 blend of two commercial products consisting of medium-chain fatty acids, lactic acid, and oregano oil (3.71 kg/ton; supplement A5+A6), and (iv) a control feed. On the farm, the Salmonella status of the fattening pigs was evaluated by taking fecal samples twice during the fattening period. At the slaughterhouse, samples were collected from the cecal contents and the ileocecal lymph nodes. Salmonella isolates were serotyped and characterized by pulsed-field gel electrophoresis. This farm had a particularly high number of pigs shedding Salmonella with a wide variety of sero- and pulsotypes. Only the feed blend based on the medium-chain fatty acids was able to significantly reduce Salmonella prevalence both on the farm and at the slaughterhouse. With this combined supplement, the Salmonella reduction in the feces at slaughter age, in cecal contents at slaughter, and the lymph nodes was 50, 36, and 67%, respectively, compared with the control animals. This promising finding calls for further investigation including cost-efficiency of this combined feed product and its effect on the animals.

Glutathione (GSH) is considered to play an important role in maintaining the integrity of the small intestine. In piglets, altered mucosal GSH levels might therefore be involved in weaning-induced changes of the small intestinal morphology and barrier function. To test this hypothesis, we aimed to challenge the mucosal GSH redox status during the first 28 days after weaning, by feeding diets containing 5% fresh linseed oil (CON), or 2.5% (OF1) or 5% (OF2) peroxidized linseed oil (peroxide value 225 mEq O-2/kg oil) and exploring the effects on gut integrity. Piglets were pair-fed and had a total daily feed allowance of 32 g/kg BW. A fourth treatment included animals that were fed the control diet ad libitum (ACON). Animals were sampled at days 5 and 28 post-weaning. The malondialdehyde (MDA) concentration and GSH redox status (GSH/GSSG E-h) were determined in blood, liver and small intestinal mucosa. Histomorphology of the duodenal and jejunal mucosa was determined, and Ussing chambers were used to assess fluorescein isothiocyanate dextran (FD4) and horseradish peroxidase (HRP) fluxes across the mucosa. Results show that peroxidized linseed oil imposed an oxidative challenge at day 28, but not at day 5 post-weaning. At day 28, increasing levels of dietary peroxides to pair-fed pigs linearly increased MDA levels in duodenal and jejunal mucosa. Moreover, FD4 fluxes were significantly increased in OF1 (+75%) and OF2 (+64%) in the duodenum, and HRP fluxes tended (P=0.099) to show similar differences, as compared to CON. This co-occurred with a significant 11 mV increase of the hepatic GSH/GSSG E-h, potentiated by a significantly increased GSH peroxidase activity for treatments OF1 (+47%) and OF2 (+63%) in liver as compared to CON. Furthermore; duodenal HRP flux significantly correlated with the hepatic glutathione disulphide (GSSG) level (r=0.650), as also observed in the jejunum for hepatic GSSG (r=0.627) and GSH/GSSG E-h (r=0.547). The jejunal permeability was not affected, but FD4 and HRP fluxes significantly correlated with the local GSH (r=0.619; r=0.733) and GSSG (r=0.635; r=0586) levels. Small intestinal histomorphology was not affected by dietary lipid peroxides, nor were there any correlations found with the GSH redox system. To conclude, under oxidative stress conditions, jejunal barrier function is related to the local and hepatic GSH redox system. It is suggested that the hepatic GSH system participates in the elimination of luminal peroxides, and thereby impacts on duodenal barrier function.

In two experiments with weaned piglets, the effects of fermented liquid feed (FLF) (produced with probiotic strain Pediococcus acidilactici, Bactocell®, Lallemand S.A.S.) on performance and some bacteriological and morpho-histological parameters of the gut were investigated, and the impact of sedimentation of the solids in the FLF thereon. In experiment I, FLF or the same dry feed (DRY) was offered ad libitum for 28 days to two groups of 15 weaned piglets (28 days of age) each (3 replicates of 5 pigs). Performance was negatively affected by feeding FLF and concomitant with that the group fed the FLF diet showed shorter villi (501 vs 550 μm) and smaller crypts (264 vs 289 μm) in the small intestine at 3 m proximal to the caecum (P < 0.05). It was assumed that these poorer results were due to sedimentation of the solids in the FLF and therefore a second experiment was conducted with sepiolite (10 g/kg) added to the feeds. Sepiolite tends to slow down the segregation of particles in slurry. The three feeding groups (weaned piglets, 27 days of age) in this experiment were DRY, DRY with probiotic (DRY+), and FLF. The group fed FLF (body weight gain (BWG) 254 g/piglet day; feed : gain ratio 1.38) did now perform better (P < 0.05) than the groups fed the DRY (BWG 184 g/piglet/day; feed : gain ratio 1.52) and DRY+ (BWG 185 g/piglet/day; feed : gain ratio 1.48) diets, which did not differ. Villus length in the small intestine at 3 m proximal to the caecum was also higher for the group fed FLF (558 μm) compared with the group fed the DRY+ diet (490 μm; P < 0.05). It was concluded that feeding FLF is beneficial to freshly weaned piglets on condition that sedimentation of the solids in the feed slurry can be controlled.

The objective of this study was to evaluate the effect of different fiber sources on jejunal digestive and absorptive physiology in weaned piglets. One hundred weaned piglets were allotted according to body weight, gender and litter to four dietary treatments. Each treatment was replicated in 5 pens of 5 pigs each. The experimental diets contained 10% of a fiber source: wheat bran (WB), maize fiber (MF), soyabean fiber (SF), or pea fiber (PF). Piglets were fed ad libitum for 30 d. Reduced villus height and villus height-to-crypt depth ratio (P PF > MF > WB. Our study indicates that SF and PF could promote apparent faecal digestibility in piglets, but this is not accompanied by better jejunal morphology or digestive enzyme activities as compared with WB.

In dry fermented sausages, myofibrillar proteins undergo intense proteolysis generating small peptides and free amino acids that play a role in flavour generation. This study aimed to identify small peptides arising from actin proteolysis, as influenced by the type of processing. Two acidification profiles were imposed, in order to mimic the pH normally obtained in southern-type and northern-type dry fermented sausages. The identification of peptides was done by liquid chromatography coupled to mass spectrometry in a data-independent positive mode of acquisition (LC-MSE). During manufacturing of the dry fermented sausages, actin was highly proteolysed, especially in nine regions of the sequence. After fermentation, 52 and 42 actin-derived peptides were identified at high and low pH, respectively, which further increased to 66 and 144 peptides, respectively, at the end of ripening. Most peptides were released at the cleavage sites of cathepsins B and D, which thus play an important role.

N-3 polyunsaturated fatty acids (PUFA) are essential for foetal development. Hence, including n-3 PUFA in the sow diet can be beneficial for reproduction. Both the amount and form (precursor fatty acids vs. long chain PUFA) of supplementation are important in this respect. Furthermore, including n-3 PUFA in the diet can have negative effects, such as decreased arachidonic acid (ARA) concentration and increased oxidative stress. This study aimed to compare the efficacy to increase eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) concentrations in the piglet, when different concentrations of linseed oil (LO, source of precursor a-linolenic acid) or fish oil (FO, source of EPA and DHA) were included in the maternal diet. Sows were fed a palm oil diet or a diet including 0.5% or 2% LO or FO from day 45 of gestation until weaning. Linoleic acid (LA) was kept constant in the diets to prevent a decrease in ARA, and all diets were supplemented with a-tocopherol acetate (150 mg/kg) and organic selenium (0.4 mg/kg) to prevent oxidative stress. Feeding 0.5% LO or 0.5% FO to the sows resulted in comparable EPA concentrations in the 5-day old piglet liver, but both diets resulted in lower EPA concentrations than when 2% LO was fed. The highest EPA concentration was obtained when 2% FO was fed. The DHA level in the piglet liver could only be increased when FO, but not LO, was fed to the sows. The 2% FO diet had no advantage over the 0.5% FO diet to increase DHA in the piglet. Despite the constant LA concentration in the sow diet, a decrease in ARA could not be avoided when LO or FO were included in the diet. Feeding 2% FO to the sows increased the malondialdehyde concentration (marker for lipid peroxidation) in sow plasma, but not in piglets.

Research showed a positive association between back fat (BF) change the week before farrowing and colostrum yield (CY). This study tested the causality of this association, hence to optimize CY by altering the sows' peripartal feeding strategy. Sows were randomly divided into 2 treatment groups at d 108 of gestation. The first group (L, n = 28) received 1.5 kg feed·d(-1), the second group (H, n = 22) received 3 times 1.5 kg feed·d(-1) until farrowing. Daily feed intake and CY were measured. Colostrum was analyzed for nutrient composition, AA and fatty acids, IgG and IgA. Sow serum was obtained at d 108 of gestation and d 1 of lactation after overnight fasting and analyzed for NEFA, (iso)butyrylcarnitine (C4), creatinine, urea, 3-OH-butyrylcarnitine (3-OH-C4), IgG, and IgA. Based on BF at d 108, sows were divided into body condition (BC) groups: skinny ( 23 mm, n = 14). We performed ANOVA with treatment and BC as fixed factors and Scheffe post-hoc test. The week before farrowing, the L group had the lowest daily feed intake (DFI; 1.5 kg), and within the H group, fat sows (3.8 kg) had a lower DFI than skinny sows (4.3 kg; p = 0.006). The H group tended to have a greater total CY (P = 0.074) and had a greater CY/kg liveborn piglet (P = 0.018) than the L group. Compared with sows in moderate BC, fat sows had a lower total CY (P = 0.044) and a lower CY/kg liveborn piglet (P = 0.005). The H group had a greater concentration of lactose (p = 0.009) and n-3 PUFA (p < 0.001) but a lower concentration of protein (p = 0.040) in colostrum than the L group. The concentration of IgG and IgA did not differ between treatment and BC groups. Serum parameters at d 108 were similar between the treatment groups and BC groups. At d 1, the H group mobilized less body fat (NEFA: p = 0.002) and protein (creatinine: p < 0.001, C4: p = 0.016) reserves but had a greater ratio urea:NEFA (p < 0.001) and less ketone bodies (3-OH-C4: p < 0.001) compared with the L group. This indicates a more balanced entry of metabolites in the citric acid cycle and thus a better support of the maternal peripartal metabolism in the H group. Serum parameters did not differ between BC groups. Both CY and composition can be influenced by the peripartal feeding strategy and BC. The highest CY and most beneficial colostrum composition were obtained when sows entered the farrowing unit in a moderate BC and were provided a high peripartal feeding strategy.

Om de varkenshouders te helpen de juiste beer voor hun bedrijf te kiezen, startte ILVO in 2017 op vraag van de sector met een testwerking, waarbij eindberen met een verschillende genetische achtergrond worden vergeleken.

Inclusion of oil palm fronds (OPF) in ruminant diets was previously reported to increase the tissue content of unsaturated fatty acids (UFAs) and reduce rumen biohydrogenation, which was in contrast with our former in vitro study. Thus, a small scale in vivo study was performed to assess the effects of different inclusion levels of OPF on UFA content of intramuscular fat (longissimus dorsi, biceps femoris) and adipose tissues (subcutaneous, perirenal). Sixteen lambs were divided into 4 treatment groups, with dietary inclusion levels of OPF of 0, 100, 200 and 300 g/kg DM, respectively. Further, the diet contained a commercial sheep/goat pellet. Diets were supplemented with soybean oil (40 g/kg DM), which was equally mixed with the whole ration. Hence, the diet particularly supplied linoleic acid (LA; 563–569 g/kg total fatty acid (FA) intake). Due to selective refusal of the OPF, actual proportion of OPF in the ingested feed was lower compared with the offered diet, i.e. 44, 137 and 170 g/kg DM. The total fat intake also differed among the treatments due to differences in feed intake. After 12 weeks on the experimental diets, the lambs were slaughtered and both intramuscular fat and adipose tissues were collected for FA analysis. No differences were observed in total FA content, proportion of C18:2 n-6 and UFA/SFA ratio in OPF inclusion groups for both intramuscular fat and adipose tissues. Hence, OPF does not seem to relatively modify UFA content of adipose or intramuscular fat.

Directing protein and energy sources towards lactation is crucial to optimise milk production in sows but how this influences colostrum yield (CY) remains unknown. The aim of this study was to identify associations between CY and the sow’s use of nutrient resources. We included 37 sows in the study that were all housed, fed and managed similarly. Parity, back fat change (ΔBF), CY and performance parameters were measured. We obtained sow serum samples 3 to 4 days before farrowing and at D1 of lactation following overnight fasting. These were analysed for non-esterified fatty acids (NEFA), urea, creatinine, (iso) butyrylcarnitine (C4) and immunoglobulins G (IgG) and A (IgA). The colostrum samples collected 3, 6 and 24 h after the birth of the first piglet were analysed for their nutrient and immunoglobulins content. The technical parameters associated with CY were parity group (a; parities 1 to 3 =value 0 v. parities 4 to 7 =value 1) and ΔBF D85-D109 of gestation (mm) (b): CY (g) =4290–842a–113b. ( R2=0.41, P

Background: Long-term outcome and quality of life (QOL) in patients requiring prolonged mechanical ventilation after failure to wean in the ICU is scarcely documented. We aimed to evaluate long-term survival and QOL in patients discharged from the ICU with a tracheostomy for difficult weaning, and with or without ventilator dependency at ICU discharge. Methods: We retrospectively investigated post-ICU trajectories and survival in patients requiring tracheostomy for difficult weaning admitted to the medical ICU of a tertiary center between 1999 and 2013, discriminating between patients who were ventilator dependent or were weaned at ICU discharge. In 2014, a QOL assessment was done in survivors with the use of the Short Form Health Survey (SF-36) and the Severe Respiratory Insufficiency questionnaire. Results: A total of 114 patients was included, of whom 59 were ventilator dependent and 55 were weaned at ICU discharge. One-year survival rates were 73 % and 69 %, respectively. Overall QOL scores for physical functioning were low, and not significantly different between patients ventilated and those weaned at ICU discharge; scores for social functioning and mental health were less below norm and similar between both groups. Conclusions: Long-term survival in patients discharged from the ICU with tracheostomy and ventilator dependency after failure to wean was not significantly different from that of patients with tracheostomy and weaned at ICU discharge. Despite the physical QOL scores being low in both groups, mental QOL was acceptable. Given the intrinsic limitations of this retrospective study, prospective and preferentially multicenter studies are required to confirm these preliminary results.

Salmonella represents a major challenge to the pig industry, as pork presents a risk for human salmonellosis. In this study, we have examined the effect of farm type on the prevalence of fattening pigs shedding Salmonella on 12 farms at risk for harboring Salmonella. On six open (grow-to-finish) and six closed (farrow-to-finish) farms, the prevalence of pigs shedding Salmonella was determined on two occasions approximately 2 months apart. The serovar, phage type, and antimicrobial resistance of the obtained Salmonella isolates were determined. On all farms, pigs shedding Salmonella were detected on at least one of the two sampling days. The mean within-herd prevalence was 7.8%. Closed farms were two times less likely to have pigs shedding Salmonella than open farms. On open farms, the odds of finding Salmonella shedding in pigs were 1.9 times higher when sampling was performed at slaughter age than when samples were taken halfway through the fattening period. Salmonella enterica serovar Typhimurium was the most predominant serotype, with a prevalence of 62 to 63% on both farm types. Of all the Salmonella Typhimurium isolates, 65% had the tetraresistant profile ASSuT (ampicillin, streptomycin, sulfonamide, and tetracycline) with or without additional resistance to trimethoprim-sulfonamide. Phage type DT120 seemed to be especially associated with this antimicrobial-resistant profile. The prevalence of Salmonella Typhimurium isolates showing resistance to ampicillin, streptomycin, tetracycline, sulfonamide, trimethoprim-sulfonamide, and lincomycin hydrochloride and spectinomycin sulfate tetrahydrate was significantly higher on open farms than on closed farms.

Thymol's antimicrobial properties urged researchers to study its effect on animal performance and intestinal health in pigs. However, thymol has the characteristic sharp odor of thyme and a bitter, aromatic, and sometime:; burning sensation which may elicit feeding aversions. The objectives in the current study were: (1) to determine the effect of dose of thymol and camphor on palatability and (2) to test the hypothesis that supplemental flavours or camphor, the latter as a known Transient Receptor Potential A1 blocker, could mitigate feed avoidance caused by thymol. Two analogous choice-feeding trials were conducted. Feed intake of the test diet was expressed as proportion of the total intake and tested by means of a one-sample Student's t-test against a set value of 50%. The preference for feed supplemented with 125, 500, 1250 and 2000 mg/kg thymol was 53.7 +/- 6.0% (P > 0.05), 47.5 +/- 5.1% (P > 0.05), 36.8 +/- 4.9% (P = 0.022), and 3.9 +/- 7.9% (P = 0.005) respectively. When feed containing 2000 mg/kg thymol with either flavour A (containing intense sweeteners) or flavour B (containing the same intense sweeteners and a caramel aroma) was opposed against a control diet, the relative intake of the test diets was 19.9 +/- 5.8% and 14.0 +/- 4.9% (both P < 0.05) respectively. When animals were offered one of these test diets and a reference diet with 2000 mg/kg thymol, animals exhibited a preference for the feed with 2000 mg/kg thymol + flavour A, but not for the feed with 2000 mg/kg thymol + flavour B. Thus, supplemental flavours containing intense sweeteners partially overcame feed avoidance caused by thymol which was less pronounced when the caramel aroma was present. Exposure to camphor (50 and 200 mg/kg) did not improve feed preference for a diet containing 1250 mg/kg thymol. Thymol's bitter taste might be largely responsible for the recorded feed refusal at high inclusion rates.

Aims: To investigate the ability of lactic acid bacteria (LAB) to convert linoleic acid (LA) and a-linolenic acid (alpha-LNA) to conjugated linoleic acid (CLA) and conjugated linolenic acid (CLNA), respectively. To assess pH and temperature influences on CLA and CLNA production by Lactobacillus sakei LMG 13558. Methods and Results: A screening of 48 LAB yielded one Lactobacillus curvatus, five Lactobacillus plantarum and four Lact. sakei strains displaying linoleate isomerase (LAI) activity. CLNA conversion percentages varied largely (1-60%). CLA conversion, occurring in three strains, was lower (2-5%). The LAI gene sequences of the ten LAI-positive strains shared 75-99% identity with the LAI gene sequence of a Lact. plantarum AS1.555. At pH 6.2, CLA and CLNA production by Lact. sakei LMG 13558 was higher at 30 degrees C than at 20 and 25 degrees C. At pH 5.5 (30 degrees C) or 37 degrees C (pH 6.2), LA was not converted and a-LNA only slightly converted. Conclusions: LAB show strain-dependent LAI activity. Production of CLA and CLNA is affected by pH and temperature, as shown for Lact. sakei LMG 13558. Significance and Impact of the Study: Several LAB produce CLA and/or CLNA, as shown for Lact. sakei and Lact. curvatus for the first time. These findings offer potential for the manufacturing of fermented functional foods.

Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A) is a promising candidate gene for selection on meat and carcass quality traits in the pig industry. In the pig, several SNPs have been reported in both coding and regulatory regions of this gene, some of which were associated with fat characteristics, but none of these associations have been confirmed and many SNPs have not yet been evaluated. Therefore, 18 PPARGC1A SNPs were genotyped in 65 slaughter pigs of a commercial hybrid population and used in an association analysis with multiple muscle and carcass traits. Several SNPs located in the 3'UTR and exon 8 and 9 of PPARGC1A were significantly (P < 0.05-0.001) associated with various carcass composition, tenderness and muscle fibre traits. They could potentially serve as DNA selection markers, if their impact was to be confirmed by a functional analysis.

Aims: The present study aimed to assess the Arcobacter contamination on bovine carcasses postevisceration and postcooling in two slaughterhouses and in ready-to-eat minced beef. Methods and Results: Carcasses (n = 247) were sampled at four sites in two slaughterhouses and 100 minced beef samples were collected at retail. Isolation was performed by a quantitative and qualitative Arcobacter selective method, and the isolates were identified by multiplex PCR, after which a part of them were characterized by enterobacterial repetitive intergenic consensus (ERIC)-PCR. Although arcobacters were isolated from 37% of the bovine carcasses postevisceration with the chest and the foreleg as most contaminated sites, cooling the carcasses for at least 24 h reduced the incidence of Arcobacter (7%) on the carcass surface significantly. Arcobacter butzleri was the species most frequently isolated, although co-contamination with multiple species also occurred. At retail, arcobacters were present in 9% of the minced beef samples, with Arcobacter butzleri as the dominant species. Conclusions: Forced air cooling of bovine carcasses for at least 24 h decreased the number of positive carcasses, but did not eliminate all arcobacters. Significance and Impact of the study: This study demonstrates that maintaining good hygiene practices throughout the food supply chain is crucial to ensure safe food products at the consumer level.

In the swine breeding industry, two economical traits are of particular importance in sires, namely, muscle growth and average daily gain (ADG). These traits are quantitative, which implies that they are under the control of multiple genes. Mutations in these genes, associated with either muscularity or growth, are useful quantitative trait nucleotides (QTN) for unraveling genetic variation of these traits and can be used in marker-assisted selection. Until now, QTN involved in muscle growth and/or ADG in pigs were identified in porcine ryanodine receptor 1 ( RYR1 ), insulin-like growth factor-2 (IGF-2), and melanocortin-4 receptor ( MC4R ). Recently, a fourth possible QTN was found in porcine myostatin ( MSTN ). All four QTN have an influence on muscle growth and/or somatic growth, so an influence of one mutation on one or more of the other mutations should not be excluded. However, although the polymorphisms in the RYR1 and the MC4R gene affect the function of the respective protein, the polymorphisms of the IGF-2 and MSTN gene influence the mRNA expression of the respective gene. Therefore, this study investigated possible interactions between the genotypes of MSTN , IGF-2, and MC4R (population 1) or the RYR1 , IGF-2, and MSTN QTN (population 2) on IGF-2 and MSTN expression in different muscle types in pigs. In both skeletal muscle and heart muscle growth, the IGF-2:MSTN ratio seems to play an important role. Also, the RYR1 genotype had a significant effect on IGF-2 expression in m. longissimus dorsi. No effect of the MC4R QTN could be seen.

The antimicrobial activity of selected essential oil (EO) components against the major culturable components of the pig gut flora has been characterised by means of an in vitro incubation model simulating the fermentation in different sections of the pig gastrointestinal tract (GIT). In a first study 7 components were screened for their antimicrobial properties. Dose–response equations were established for the 4 components with the highest potential in a second study. Binary combinations were tested as well, and the interaction effects were evaluated following the isobole method. The results of both studies indicated that carvacrol, thymol, eugenol and trans- cinnamaldehyde give opportunities to modulate the flora and fermentation pattern of the GIT of pigs. Eucalyptol, terpinen-4-ol and trans -anethole were found not to have interesting effects on the growth of the pig gut flora. The minimum concentration for carvacrol, thymol, eugenol and trans -cinnamaldehyde in jejunal simulations to reduce the number of total anaerobic bacteria compared to control with a probability of 99.7% was 255, 258, 223 and 56 mg/L respectively. This strong activity of trans -cinnamaldehyde was due to its progressively increasing effect against coliform bacteria; a dose of 104 mg/L gave a reduction of 1 log 10 CFU/mL vs . 371, 400 and 565 mg/L for carvacrol, thymol and eugenol respectively. However, trans -cinnamaldehyde showed clearly less inhibitory activity towards lactobacilli than carvacrol and thymol. Therefore, the use of trans- cinnamaldehyde (for example 100 mg/L) and to a lesser extent eugenol could result in a shift in the microbial ecology in favour of lactic acid producing bacteria and reducing the number of coliform bacteria. Carvacrol and thymol showed very similar and non-selective antimicrobial properties. Their effect was more pronounced in acidic media and demonstrated a rapidly increasing bactericidal effect from a certain concentration on (400–500 mg/L in jejunal simulations). The inhibition of the production of total short chain fatty acids (SCFA) in jejunal simulations by these 4 candidates was related to their effect against coliform bacteria, however they did not alter the lactic acid and ammonia concentrations. Few combinations demonstrated synergism; most mixtures showed zero interaction or antagonism. Carvacrol + thymol (ratio ≥1) was synergistic against total anaerobic bacteria in jejunal simulations, however this effect was rather small. In caecal simulations, carvacrol, thymol and trans -cinnamaldehyde were equally effective while eugenol had an effect only on coliforms. These data on the in vitro antimicrobial activities of EO components give support for a better control of the gastrointestinal bacterial community and the design of alternative growth promoters. Their in vivo potential is also discussed.

In this paper the selection of potential probiotic strains for producing fermented liquid feed (FLF) for pigs is presented. One hundred and forty six strains of lactic acid bacteria were isolated from ileal digesta of piglets, cecal digesta of slaughter pigs and FLF from a preliminary trial at our laboratory. The strains were identified with repetitive-element PCR and partial 16S rRNA sequencing and screened for acidification potential. Ten of the strains were selected and their culture supernatant was checked for antibacterial activity against Salmonella spp. Also, they were tested in vitro in batch fermentations at 30 °C for 72 h, for their capacity to produce FLF (water:feed ratio of 4:1) with a concentration of acetic acid less than 40 mmol/L and of lactic acid above 100 mmol/L, resulting in a pH below 4.5. The Lactobacillus strains MB 3123 ( L. johnsonii ), MB 3182 ( L. salivarius group) and MB 3083 ( L. plantarum ) were found to be very effective for the production of FLF. The FLF produced by including this strain had a pH drop from 5.9 to 4.2, 4.3 and 4.4 after 24 h and to 4.1 after 48 h of fermentation. Also, these three strains showed high antimicrobial activity against Salmonella spp. and produced more than 100 mmol/L lactic acid after 48 h fermentation. The MB 3170 strain increased the lactic acid concentration above 100 mmol/L after 48 h, but at 24 h the pH was only 4.5. The results indicate that it is possible to screen for probiotic strains capable of fermenting feeds and of producing high quantities of lactic acid with possible antimicrobial effects in the gastro-intestinal tract of pigs.