Nadine Buys

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.

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.

Haematological characteristics predicting susceptibility for ascites. 2. High haematocrit values in juvenile chickens.

1. Male broilers of two different genetic stocks, a pure broiler sire line (A) and commercially available Ross broilers (B), were used to study the effect of differences in haematocrit values in 12-d-old chickens on the development of ascitic symptoms. Body weight gain (BWG), feed intake (FI) and feed conversion ratio (FRC) were measured from 2 to 5 weeks of age. Mortality was recorded from 2 to 6 weeks. The birds were kept at a low ambient temperature to stimulate the incidence of ascites. 2. From each stock 32 birds with the highest (High Ht) and 32 birds with the lowest (Low Ht) haematocrit values in venous blood were selected at 12 d of age for an examination on susceptibility for the ascites syndrome at 5 weeks. 3. At 2 weeks 448 birds per stock (including High Ht and Low Ht birds) were allotted to 32 floor pens (1 High Ht and 1 Low Ht in each pen). Venous blood samples were taken weekly in High Ht and Low Ht birds for haematocrit measurements and at week 5 also thyroid hormone (T3, T4) concentrations in plasma were measured. At 5 weeks all High Ht and Low Ht birds were examined post-mortem and arterial pressure index, heart weight, lung weight and liver weight (all relative to body weight) were recorded. High values for arterial pressure index, relative heart and liver weights and low values for relative lung weights and plasma thyroid hormone were considered to be indicators for ascites susceptibility. 4. Stock A, with the highest ascites mortality, had lower values for BWG and FCR than stock B. Throughout, a clear difference in Ht values between High Ht and Low Ht birds was maintained. No significant effects of 12-d haematocrit values were found on the incidence of ascitic symptoms until week 5. High Ht values tended to correlate with low relative lung weights and low plasma T3 concentrations in High Ht birds. 5. Within the groups of selected birds, there was an effect of stock on ascitic symptoms (arterial pressure index, relative heart weight and T3 values) at week 5. This is consistent with a higher ascites mortality in flock A than in flock B, over the whole period up to 6 weeks. Until 4 weeks both A and B were similar with respect to mean Ht values of High Ht and Low Ht groups. After 4 weeks Ht values were very high in the High Ht birds of stock A, possibly as a result of the susceptibility for ascites of stock A. There was a significant interaction between stock and Ht values on the ascites-related variable arterial pressure index. Only in stock A was high arterial pressure at 5 weeks related to high Ht values at d 12. 6. Overall it was concluded that a high Ht in blood of juvenile chickens has limited practical value in predicting incidence of ascites at 5 weeks of age.

Haematological characteristics predicting susceptibility for ascites. 1. High carbon dioxide tensions in juvenile chickens

1. Male broilers of two different genetic stocks, a pure broiler sire line (A) and commercially available Ross broilers (B), were used to study the effect of haematological characteristics in juvenile chickens on the development of clinical ascitic signs. Production performance (body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR)) from 448 birds per stock was measured from 2 to 5 weeks of age. Mortality was recorded from 2 to 6 weeks of age. The birds were housed at a low ambient temperature to stimulate the incidence of ascites. 2. From each stock, 32 birds with the highest (high risk: HRc) and 32 birds with the lowest (low risk: LRc) carbon dioxide tensions (pCO2) in venous blood were selected at 11 d of age. These birds were marked for future blood sampling to determine changes in pCO2 with age to relate these values to ascites susceptibility. 3. At 2 weeks of age all birds (including HRc and LRc birds) were allotted to 32 floor pens (one HRc and one LRc in each pen) per stock. Venous blood samples were collected weekly from HRc and LRc birds for blood gas analysis and haematocrit, and at week 5 also for thyroid hormone (T3, T4) concentrations in plasma. At 5 weeks of age all HRc and LRc birds were examined post-mortem, relative heart, lung, and liver weights and arterial pressure index (API) values were recorded. 4. Birds from stock A showed a lower BWG and FCR and notably higher ascites mortality compared with stock B. An effect of pCO2 tensions at d 11 was found on the incidence of ascitic signs in selected birds of both stocks up to week 5. From the HRc groups 30% of the birds showed ascitic signs, whereas this was only 8% in the LRc group. LRc birds of stock B in particular showed constant low API values (20 ± 3%) and none of these birds showed signs of ascites. 5. Our results suggest that the ascites problem in Ross birds can be eliminated by selection for low pCO2 tensions in venous blood. Stock effects on API, liver weight, lung weight, and plasma thyroid hormone independent of pCO2 showed a more complex picture of the ascitic signs in stock A compared with B. 6. We concluded that in this experiment a high pCO2 tension in venous blood measured at d 11 was a reliable predictor for ascites susceptibility observed at 5 weeks of age. A low pCO2 tension provides an appropriate criterion for genetic selection, whereas a high pCO2 tension emphasises the necessity for intensive management in poultry houses.

Genetic parameters for chronic progressive lymphedema in Belgian draught horses

The aim of this study was to investigate the role of coprophagous behavior in suckling rabbit on the implantation of caecal microbiota and to try improving the health status of rabbits modifying this behavior. Three groups were compared: in FM group (n=24 litters), pups had free access to maternal hard feces, in NF group (n=28), ingestion of hard feces was prevented, and in FF group (n=28), pups had access only to hard feces excreted by foreign females (n = 5, 7 and 9 feces from 2 to 13 d, 14 to 17 d, 18 to 20 d, respectively). Pup mortality, excretion and ingestion of feces were measured daily. Bacterial composition was assessed by 454 pyrosequencing of the V3-V4 region of 16S RNA genes at 14, 35, 49 and 80 d of age. The total number of feces excreted by the does from 2 to 20 d after delivery ranged widely, but was similar among groups (16.1 ± 12.6 feces doe-1). Ingestion of feces was 3 times greater in FF than in FM group (35.6 vs 9.9, p < 0.001). From 1 to 80 d of age the FF and NF groups exhibited respectively the lowest (9.3%) and highest (22.8%) pup mortality compared to FM group (15.5 %, p = 0.03). At age 14 d the caecal bacterial community was dominated by Bacteroidetes phyla (63.3%), Bacteroidaceae family (36.0%) and Bacteriodes genus (36.0%). With increasing age, Firmicutes phyla, Lachnospiraceae and Ruminococcaceae families became the dominant taxa (92.0%, 44.0 % and 37.9 %, respectively at 80 d of age). Impairment of feces ingestion delayed this ecological succession, with greater and lower relative abundance of Bacteroidaceae and Ruminococcaceae respectively in NF than the two other groups at age 35 d (p < 0.1). In conclusion, the coprophagous behaviour of suckling rabbits is implicated in the maturation of caecal bacterial microbiota and stimulation of this natural behavior improve the health status of animals and could be used to limit the use of antibiotics.Equitherapy is widely practiced and its positive effects are quite well known. However, dynamics of communication between the horse, the user and the therapist is little described. Here, we proposed a pilot study that focused on visual attention of these three partners at two moments: before and during horseback riding (HR). The triad had been observed during the equitherapy session (around 45 min) of four boys with autism (6-9 yo). Ten-second scan samplings recorded the gaze direction of each subject. Data were converted in percentage of time. Horses had mostly gazed at physical environment both before (76.2±6.6%) and during (91.6±1.6%) HR. Human they mostly gazed was the therapist before HR (8.7±3.3%). Similarly, boys mostly gazed at physical environment throughout the session (61.7±17.1% and 46.9±15.3%, respectively). Focus on social partner showed that boys mostly gazed at horse especially during HR (8.7±4.7% and 13.2±9.6% respectively). Likewise their visual attention to humans was enhanced during HR (9.0±1.5% to 19.3±3.1%). At last, before HR, therapists mostly gazed at boy (33.8±9.4%) and horse (38.4±16.7%). During HR, their attention on boy increased slightly (36.7±10.0%) but surprisingly, their attention on horse decreased extremely (7.2±0.9%) in favor of the physical environment (26.1±11.5% to 50.3±12.7%). This pilot study on visual attention during equitherapy suggested that children with autism, whose attentional skills are impaired, seemed to be more attentive to social partners during HR. In this situation, horses seemed few attentive to humans that might be explain by either apathy or working situation. Finally, the reduction of therapist’s visual attention to the horse during HR suggests a decrease in vigilance. This was an example of routine where human pays less attention to animal, which constituted one of the most accidental situations. Thus, therapists must be greatly attentive when horses are used in such therapeutic programs where safety is indispensable.Similar farrowing progress among sows housed in crates and pens Pedersen, Janni Hales; Moustsen, V. A.; Devreese, Anne Michéle; Hansen, Christian Fink Published in: European Association for Animal Production. Annual Meeting. Book of Abstracts DOI: 10.3920/978-90-8686-782-0 Publication date: 2013 Document Version Early version, also known as pre-print Citation for published version (APA): Pedersen, J. H., Moustsen, V. A., Devreese, A. M., & Hansen, C. F. (2013). Similar farrowing progress among sows housed in crates and pens. DOI: 10.3920/978-90-8686-782-0The EAAP AFWG was constituted in 2007 with a view t o enhancing the role of animal fibre in EU27, utilizing an approach based on science and technology. Although an unrecorded and neglected product, annual production of wool from 6 2m breeding sheep (Eurostat) alone is substantial at an estimated 186,000 tonnes (FAO). R ecent outputs include organised symposia and publications defining current knowledge. In rec ognising the need for better networks of scientists and technologists, a total of 5 applicat ions for financial support has been made to the EC COST Framework since 2010. Such applications , by initial pre-proposal, are assessed in 6 categories with a maximum score of 6 for each, giving a maximum score of 36. Preproposals scoring most highly, on average, are invi ted to submit a full proposal. Evaluation has been characterised by large variation in scores of individual assessors. For one example, scores of 36, 33, 32, 32, 28, 21,16 were awarded by 7 assessors, giving mean value = 28.3; SD = 7.23; CV%= 25.5. The divergence of the median v lue of 32 from the mean (28.3) shows a skewed distribution. Removal of the two low est outliers, gives a mean = 32.2; SD= 2.86; CV%= 8.9 and median = 32 and removes the skew . The use in ranking, of such a simple average of means, is clearly unreliable. Another ex ample, with a mean score of 31.25, gave rise to an invitation to submit a full proposal. Th is was done, involving 14 EU partner, and 4 international “reciprocal agreement”, countries. Th e outcome of this application was a score of 53, and below the cut-off score of 55, for furth er progression. The consensus conclusion of evaluation was that “the expected benefits are like ly to be non-European”. This conclusion is surprising and essentially without explanation. The selection of evaluators remains a concern. 64 th EAAP Annual meeting, 25-30 August, 2013, Nantes, France Symposium on South American Camelids and other Fibre AnimalsThe role of the agouti gene in white phenotype was explored in mice. The agouti signalling protein (ASP) can inhibit the differentiation of melanoblasts through the inhibition of the alfa-MSH-induced expression of microphtalmia (MITF) and its binding to a M box regulatory element. The level of microphtalmia in the cells is reduced. To investigate the role of agouti in this phenotype we characterised the transcript structures an relative mRNA expression levels in 13 white alpaca. The reverse transcription analysis of mRNA purified from skin biopsies revealed the presence of three transcripts with different 5’untranslated regions (UTRs) and color specific expression. One of the transcripts, possibly originating from a duplication event (intra-chromosomal recombination) of the agouti gene is characterised by a 5’UTR containing 142 bp of the NCPOA6 gene sequence. Furthermore, the raltive level expression analysis of mRNA demonstrates that the agouti gene has upregulated expression in white skin, suggesting a pleiotropic effect of agouti gene in the white phenotype. Resumen : Recombinacion cromosomica del gen agouti en alpacas blancas. Fue explorado en ratones el rol del gen agouti en el fenoripo blanco. La protein senalarizadora agouti (ASP) puede inibir la diferenciacion de los melanoblastos a traves de la inhibicion de la expresion alfa-MSH inducida de macroftalmia (MITF) y su union al elemento regulador Mbox. El nivel de macroftalmia en las celulas se reduce. Para investigar el rol del agouti en este fenotipo, caracterizamos las estructuras transcriptas a una relativa expresion del mRNA en 13 alpacas blancas blancas. El analisis de transcripcion reversa del mRNA purificado a partir de las biopsias de piel, revelaron la presencia de tres transciptos con diferentes regiones no traducidas del extremo 5’ (5’UTR) y expresiones de color especificas. Uno de los transcriptos, posiblemente procedente de un evento de duplicacion (recombinacion intra-cromosomico) del gen aguti se caracteriza por un 5’ UTR que contiene 142 pb del gen NCPOA6. Por otra parte, el analisis del nivel relativo de expresion del mRNA demuestra que el gen agouti tiene sobre expresion reguladora en piel blanca, lo que sugiere un efecto pleiotropico del gen agouti en el fenotipo blanco.The agouti gene encodes agouti signalling protein (ASIP) whic h regulates pheomelanin and eumelanin synthesis in mammals. To investigate the role of agouti in coat color variation of alpaca, we characterised the agouti gene on 27 black and 12 brown alpaca. The exon-4 hosts three loss-of-function recessive mutations: g.3836C >T, g.3896G>A and g.3866_3923del57, involved in eumelanin synthesis. The deletion at th e position p.C109-Rdel19 eliminates the two beta sheets and the R-F-F- motif from the agout i functional domain, which are essential against alfa-MSH. Therefore, the deleted allele app ears to lose function. The other ANPs observed at the amino acid position 98 and 118 chan ge the conserved R to C and the R-F-Fmotif into H-F-F-. The R-F-F- motif is important fo r functioning at MCRs; the disruption of this motif may result in a non functional agouti pr otein since the alteration of residues in and around R-F-F- causes a decrease in agouti protein i nhibition of alfa-MSH binding to MCRs during signal transduction. The three mutations are randomly distributed among the black alpaca. In our sample, we observed two genotypes : g.3836C>T/g.3896G>A (10 animals) and g.3836C>T/g.3866_3923del57 (17 animals). Among the brown alpaca, 2 are homozygous for the wild allele, 12 are heterozygous for g.3896G>A mutation, carriers for black phenotype.