Intact brown seaweed (Ascophyllum nodosum) in diets of weaned piglets: effects on performance, gut bacteria and morphology and plasma oxidative status

The aim was to assess the effects of intact dried Ascophyllum nodosum seaweed on piglet performances, gut bacteria and function and plasma oxidative status. A total of 160 weaned piglets (21 days, 6.59 ± 0.91 kg) were allocated to four dietary treatments with eight pen replicates of five animals each for 28 days: a control diet; based on cereals, soybean meal and milk products, and three basal diets supplemented with either 2.5, 5.0 or 10.0 g dried seaweed per kg. At day 12/13 one piglet from each pen was sacrificed. Plasma samples were taken to determine parameters of oxidative status. Digesta were sampled for microbiological plate countings onto selective media and molecular analysis using PCR-DGGE. Small intestinal tissue was taken for morphological and electro-physiological determinations. Data were analysed by a linear model with treatment as fixed effect. A. nodosum supplementation had no effect on daily weight gain, nor did it alter feed conversion ratio. Plate countings failed to reveal differences among treatments. Dendograms prepared using PCR-DGGE banding patterns did not indicate clustering of microbial profiles based on diet supplement. Plasma oxidative status and outcome of morphology and of electro-physiological measurements from gut tissues were similar for all treatments. Thus, the addition of A. nodosum seaweed to well digestible diets did not enhance performances of piglets nor some gut health parameters and plasma oxidative status.

Effect of rate of pH decline on muscle enzyme activities in two pig lines

Muscle enzyme activities were measured in m. transversus abdominis (TA) samples of two pig lines, differing in stress sensitivity and in breeding objectives. Animals of line one were stress sensitive and selected for a high carcass lean content (LEAN), those of line two were homozygous stress resistant and selected for maximum live weight gain (GROWTH). Muscle samples of 16 pigs per line were excised at 1 h and sampled at 3 h post mortem. Boars, gilts and barrows were almost equally represented. Pigs of line GROWTH had a higher fat and lean tissue gain (P<0.01) and a lower carcass lean content (P<0.001) than those of line LEAN. Lower activities of μ-calpain, m-calpain, pyroglutamyl aminopeptidase I, acid lipase and neutral phospholipase were measured in TA muscle samples of line LEAN compared with line GROWTH (P<0.05). Activities of dipeptidyl peptidase IV and acid phospholipase tended to be somewhat lower for line LEAN, whereas activities of calpastatin, cathepsin (B+L) and cathepsin D were not different. Sex-class effects were analogous to line effects. Significant correlation coefficients between activities of several enzymes and pH values 1 h post mortem, both within and across lines, suggest that lower enzyme activities are a consequence of a more pronounced denaturation due to a faster post mortem pH decline.

Effect of dietary energy and protein levels on fatty acid composition of intramuscular fat in double-muscled Belgian Blue bulls

Seventy six Belgian Blue (BB) bulls, with double-muscled conformation, were randomly allocated to six dietary treatments in a 2 × 3 factorial experiment. The treatments included low (N(L)=127 g CP/kg DM), medium (N(M)=153 g CP/kg DM) and high (N(H)=172 g CP/kg DM) levels of dietary protein in combination with low (E(L)=7.38 MJ ME/kg DM) and high (E(H)=8.03 MJ ME/kg DM) levels of dietary energy. Fatty acid composition was determined on total lipid samples of the M. longissimus thoracis of all animals and on the separated triacylglycerol and polar lipid fatty acid fractions of the medium-protein group. Dietary energy and protein levels influenced the carcass characteristics of BB bulls but the effects were small. Carcass fat cover score, carcass fat content and intramuscular fat content were slightly but significantly higher in the animals on the high versus the low energy diets. The overall intramuscular fat content was very low (<1%) and the overall polyunsaturated:saturated fatty acid ratio (0.39) high compared to normal figures for beef. The high versus the low dietary energy level increased the monounsaturated (P<0.001) and decreased the polyunsaturated (P<0.001) fatty acid proportion with no change in the saturated fatty acid proportion. This may have been due in part to the addition of beef tallow to increase the energy level of the diet. Concomitant shifts in the individual fatty acids included increased proportions of C14:0 (P<0.001), C16:0 (P<0.03), C16:1 (P<0.01), C18:1 (P<0.001) and decreased proportions of C18:2 (P<0.001) and C20:4 (P<0.001). Increasing dietary protein levels had inconsistent effects on the fatty acid profiles. The proportion of polar lipid fatty acids in the total fatty acids was 0.34 and 0.25 for the E(L) and E(H) group, respectively, in the Nm treatment group. Changes in fatty acid proportions of the triacylglycerol fatty acid fraction were similar to those seen in the total lipid fatty acids when related to dietary energy level, but no significant changes in the polar lipid fatty acid proportions were observed. Significant linear relationships were found between measures of carcass and muscle fatness and fatty acid proportions. With increasing muscle total fatty acid content, saturated and monounsaturated fatty acid proportions increased (r=0.38 and r=0.55, respectively, P<0.01) and the polyunsaturated fatty acid proportion decreased (r=-0.73, P<0.01). The diet had some effects but the relatively unsaturated intramuscular fatty acid composition was mainly related to the low total fat content of the BB animals.

Feasibility of the Ussing chamber technique for the determination of in vitro jejunal permeability of passively absorbed compounds in different animal species

The aim of this study was to assess the feasibility of the Ussing chamber technique for the determination of the jejunal permeability of passively absorbed, high permeability model compounds (acetaminophen and ketoprofen) in different animal species. Additionally, electrophysiological measurements and histological examination of pre- and post-incubation tissue specimens were performed. Apparent permeability coefficients of turkey and dog jejunum were low and highly variable due to tissue fragility caused by differences in thickness of the remaining intestinal layers after stripping and resulting in severe damage. Pig and horse jejunum were markedly more suitable for permeability determinations and mild signs of deterioration were noticed after 120 min of incubation. Transepithelial electrical resistance and potential difference did not correlate well with the observed tissue damage. From these data, the Ussing chamber technique appears to allow for permeability measurements within a species, but seems unsuitable for interspecies permeability comparison. However, further validation of the method with low permeability compounds and actively transported compounds is needed.

[The mother-infant encounter at birth must be protected]

The medical decision to separate a newborn baby from his or her mother is frequent. This medical practice must be evaluated. The scientific literature regarding humans and other mammals was reviewed in order to describe the physiology of the interactions between mother and offspring and the consequences of disrupting their interactions around birth. Mother-infant bonding is common to all mammals. Attachment is the result of three mechanisms: behavioral programing, secretion of neuroendocrine substrates, and activation of sensory cues. Breastfeeding is a fourth component that plays a crucial role. Experimental research provides evidence that early-life maternal separation can alter biological responses to stress, disturb learning behaviors, and impair social skills. Recent advances in epigenetic research may partly explain how neonatal maternal deprivation at birth can lead to biological and behavioral disorders in adulthood. Therefore, the decision to separate a newborn infant from his or her mother is not harmless and must be carefully considered. In order to better take into account these data, the organization of perinatal care in France should be revised.

[Eosinophilic esophagitis. Clinical presentation, allergology and treatment: a series of 22 children]

BACKGROUND AND AIMS

Eosinophilic esophagitis (EE) is a disorder characterized by severe eosinophilic infiltration of the esophagus, with dysphagia and gastroesophageal reflux disease (GERD) symptoms unresponsive to acid blockade therapy but responsive to the removal of dietary antigens. We report information relating to children diagnosed with EE in Nice, France, over a 6-year period.

PATIENTS AND METHODS

We conducted a retrospective study between January 1, 2004, and July 31, 2009, evaluating all children diagnosed with EE. Clinical and demographic data, endoscopic and histological findings, allergology data, and results of treatment were collected and evaluated.

RESULTS

A total of 22 patients, 19 males, median age 9.5 years (range: 0.8-19 years) were reviewed: 7 presented isolated dysphagia, 6 presented GERD symptoms, and 9 both dysphagia and GERD symptoms. Endoscopically, 14 had multiple esophageal white plaques, 7 had linear furrowing, 5 had circular "tracheal" rings, and 5 esophageal narrowing. The median number of esophageal eosinophils/high power field (×400) was 30 (range: 15-80). Eosinophils were localized in the distal, middle, and upper esophagus. Immunoallergy analysis findings were: high peripheral eosinophil count (74%), high total IgE level (65%), high eosinophil cationic protein (ECP) level (90%) with a median value of 69.5 μg/l and high urinary leukotriene E4 (88%). Food antigen sensitization was positive in skin-prick testing in 11 of 18 and in atopy-patch testing in 9 of 17. Dietary restriction improved clinical symptoms in 5 of 10 and local corticotherapy with viscous budesonide improved clinical symptoms in 9 out of 10.

CONCLUSION

EE diagnosis must be considered in children with dysphagia or GERD who do not respond to acid blockade therapy. ECP may be used to guide diagnosis. Local corticotherapy is effective.

Influence of soiling on boar taint in boars

It has been suggested that skatole, one of the main compounds responsible for boar taint, can be lowered by keeping pigs clean, as skatole can be absorbed through skin and/or lungs (Hansen, Larsen, Jensen, HansenMoller & Bartongade, 1994). With this experiment, we further investigated this hypothesis by comparing extremely clean with extremely dirty animals with regard to the occurrence of boar taint. One group of boars was washed daily and pens were mucked on and littered down daily (CLEAN), a second group of boars was rubbed with faeces daily (DIRTY) and a third group of boars was kept in control conditions (CONTROL). The treatment was performed during the last four weeks before slaughter. According to the standardised consumer panel evaluations, boars subjected to extra soiling had a higher concentration of boar taint than boars that were kept extra clean. In contrast, expert panels judged general meat flavour to be inferior in CLEAN than CONTROL pigs. The home consumer panel, the hot iron method, and laboratory analyses, i.e., the presence of indole, skatole and androstenone in fat and serum, all showed no significant differences. So no clear indications towards skatole reduction by improving cleanliness of pigs were found.

Effects of diet, age and gender on the polyunsaturated fatty acid composition of broiler anatomical compartments

1. The objective of this study was to investigate the effect of dietary fatty acid (FA) composition, age, and gender on the FA composition of different broiler anatomical compartments. Four dietary fat sources (palm fat, P; soybean oil, S; linseed oil, L; fish oil, F) were added to a wheat-soybean meal based diet at 30 g/kg in addition to 50 g/kg palm fat. Diets were fed separately to female and male birds from d 1 to either d 21 or d 42 of age. 2. The total FA content (mg/100 g tissue) and the FA composition (g/100 g FAME) was determined in 7 anatomical compartments (skinless thigh muscle, skinless breast muscle, liver, heart, brain, abdominal fat pad, and remainders plus carcase trimmings named Rest compartment). The FA profiles differed greatly among compartments and were strongly affected by diet. 3. The S diet resulted in a 2-3-fold increase of the proportion of C18:2n-6 and C20:4n-6 in all compartments compared to the other diets, except for brain. 4. The response in the proportion of C18:3n-3 following feeding the L diet was much greater, with 4-20-fold increases compared to the other diets, except again for brain. 5. In all compartments except brain, the L diet resulted in approximately a 2-fold increase in the proportion of C22:6n-3 compared to the P and S diets and smaller, but also significant, increases for C20:5n-3 and C22:5n-3. 6. The proportions of C20:5n-3, C22:5n-3 and C22:6n-3 were much higher on the F diet in all compartments, except for brain, compared to the P and S diets. The F diet resulted in higher proportions of C22:6n-3 than the proportions of C20:5n-3 and C22:5n-3 in breast and thigh meat, and liver, in contrast to the other diets. 7. Brain was less responsive than other tissues to changes in the dietary FA composition. The proportion of C22:6n-3 in brain was similar on the L and F diets. 8. The effect of gender on the FA composition of different anatomical compartments was marginal. The long-chain n-3 and n-6 PUFA in breast, liver, and brain decreased with age.

Genetic parameters for intramuscular fatty acid composition and metabolism in pigs

The aim of this study was to estimate genetic parameters for pork intramuscular fatty acid (FA) composition and indices for desaturase and elongase activities involved in n-3 and n-6 PUFA metabolism. The LM of 437 slaughter pigs was analyzed for FA composition (expressed as g/100 g of FA). Indices for enzyme activities were calculated from product to precursor FA ratios. Genetic parameters were estimated with single- and multi-trait animal models. The total FA content, reflecting the intramuscular fat content, was either included or not in the model. Results from the models without total FA content showed relatively high heritability estimates, generally above 0.50, for the proportion of the most important MUFA and PUFA, compared with much smaller values for the SFA. When total FA content was included in the models, heritability values decreased (P < 0.001) for most individual FA and for all sums of FA groups, except for C18:0, C18:3n-6, and C18:3n-3. Heritability estimates for the ratios C20:4n-6/C18:2n-6 and C22:6n-3/C18:3n-3, reflecting the overall conversion in the n-6 and n-3 PUFA pathway, respectively, were 0.29 and 0.35, respectively, with total FA content in the model and increased to 0.38 and 0.49, respectively, if total FA content was not in the model. Heritabilities for other more specific indices were of the same order. Genetic correlations between PUFA proportions and indices for enzyme activities with ADG were mostly negative, whereas the correlations with carcass lean meat percentage were mostly positive. It was concluded that there is meaningful genetic variation for long-chain PUFA metabolism that is only partly dependent on the carcass and muscle fat content. This may allow selection for improved FA composition of pork.

Interactions between genes involved in growth and muscularity in pigs: IGF-2, myostatin, ryanodine receptor 1, and melanocortin-4 receptor

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.