Genetic analysis of longitudinal measurements of feed intake in Piétrain sire lines

in Journal of Animal Science (in press)

La dimension "travail", un élément clé pour le maintien de nos systèmes laitiers

in Centre wallon de Recherches agronomomiques (Ed.) 18ème Carrefour des Productions Animales "Nouvelles approches pour une optimisation de nos élevages laitiers" (2013)

Les agriculteurs sont les principaux architectes du milieu rural wallon. En effet, ils assurent la gestion de près de la moitié de la superficie de la Wallonie. On observe néanmoins, depuis quelques ... [more ▼]

Les agriculteurs sont les principaux architectes du milieu rural wallon. En effet, ils assurent la gestion de près de la moitié de la superficie de la Wallonie. On observe néanmoins, depuis quelques années, une régression lente (3%/an) et constante de leur effectif. Confrontés à un contexte changeant, de plus en plus concurrentiel, les agriculteurs sont face à des choix stratégiques difficiles en vue d’optimiser l’efficience de leur exploitation. Pour y parvenir, ils doivent mener une réflexion globale de leur mode de production et intégrer tous les aspects assurant la durabilité de leur exploitation. Pour les aider dans cette démarche, une analyse de la durabilité de 90 exploitations « 100% Lait » (>95% de vaches laitières et pas de culture de rente) a été réalisée dans le cadre de DuraLait et de DuraLait Plus. Ces études sont subsidiées par la DGARNE, Direction de la Qualité. Les piliers économique et social de la durabilité ont été plus particulièrement étudiés dans ces projets. L’organisation du travail a été spécifiquement traitée car elle constitue un enjeu essentiel pour l’avenir de l’agriculture. En effet, les agriculteurs souhaitent soulager la pénibilité de leur travail. Dans un contexte économique difficile, cette dimension est essentielle pour envisager le maintien de l’agriculture dans notre région. Le présent article s’intéresse uniquement aux données relatives à l’organisation du travail. [less ▲]

Gaseous emissions from fattening pigs offered an ad libitum high-fibre diet and kept on fully slatted floor: preliminary results

in Proceedings of the 2nd Scientific Meeting of the Faculty of Veterinary Medicine (Liège – Belgium) (2012)

According to the literature, the diet composition of livestock can influence polluting gas emissions from agriculture. The aim of this preliminary study was to measure gaseous emissions from fattening ... [more ▼]

According to the literature, the diet composition of livestock can influence polluting gas emissions from agriculture. The aim of this preliminary study was to measure gaseous emissions from fattening pigs offered an ad libitum high-fibre diet (HFD) and kept on fully slatted floor. A batch of 24 fattening pigs was divided into two homogeneous groups randomly allocated to a treatment: conventional cereals-based diet or sugar beet pulpbased diet (HFD). With HFD, a significant decrease of animal performance was observed (837 vs. 962 g for the average daily gain). With pigs offered HFD, gaseous emissions per pig were significantly lower for NH3 (-30%, 6.64 vs. 9.47 g/d; P<0.05) and significantly greater for CH4 (+40%, 6.46 vs. 4.60 g/d; P<0.05). The emissions of N2O (0.34 g/d), CO2equivalent (0.27 kg/d), CO2 (1.68 kg/d) were not significantly influenced by the diet. Due to a more important microbial activity with HFD, the lower NH3-emissions could be attributed to the shift of a part of excreted nitrogen from urine (as urea) to faeces (as protein form), and to a lower slurry pH explained by the increase of volatile fatty acid content. The higher CH4-emissions could be explained by a greater production in the digestive tract and in the slurry due to fibre fermentations. In conclusion, HFD allowed decreasing NH3- and increasing CH4-emissions. However, in terms of climate change, this increase was offset by the decrease of indirect N2O-emissions due to NH3-emission decrease, as indicated by the similar CO2equivalent-emissions in the two groups. [less ▲]

Ammonia emissions associated to slatted floor and bedded floor systems for fattening pigs and gestating sows

in Proceedings of the International Symposium on Emissions of Gas and Dust from Livestock (2012)

Effets des fibres et du type de sol sur les émissions de gaz à effet de serre et d'ammoniac associées à l’élevage de truies

in 44èmes Journées de la Recherche Porcine (2012)

A study was carried out to investigate the effect of dietary fibre content (23% of non-starch polysaccharides (NSP) with a standard diet based on cereals vs. 44% of NSP with a fibrous diet based on sugar ... [more ▼]

A study was carried out to investigate the effect of dietary fibre content (23% of non-starch polysaccharides (NSP) with a standard diet based on cereals vs. 44% of NSP with a fibrous diet based on sugar beet pulp) and the floor type (slatted floor vs. straw-based deep litter) on emissions of ammonia (NH3), nitrous oxide (N2O), methane (CH4) and CO2-equivalents (Eq-CO2). Six successive batches of 10 gestating sows were divided into 2 groups kept in 2 experimental rooms differing by the floor type. The standard diet was administered to the sows of the first 3 batches, the fibrous diet to the sows of the next 3 batches. Emissions were measured by infra-red photoacoustic detection. With the slatted floor, the fibrous diet decreased NH3 emission (12.0 vs. 15.5 g sow-1.d-1) but increased the Eq-CO2 emissions (0.69 vs. 0.57 kg sow-1.d-1) in relation to an increase of CH4 emissions (18.4 vs. 12.8 g sow-1.d-1), the N2O emissions not being impacted by the diet, with value around 0.62 g sow-1.d-1. With the straw-bedded floor, the fibrous diet increased the emissions of NH3 (12.3 vs. 9.2 g sow-1.d-1) and CH4 (14.6 vs. 9.6 g sow-1.d-1) but decreased N2O emissions (0.99 vs. 1.64 g/ sow-1.d-1) with the consequence that Eq-CO2 emissions were similar for the two diets, around 0.74 kg sow-1.d-1. [less ▲]

Advanced genetic models for Piétrain boars involved in crossbreeding in the Walloon Region using test station and on-farm phenotypic and genomic data

Poster (2012)

Since 2007 the Walloon Region is acquiring a new advanced genetic evaluation program for Piétrain boars. Comprehensive models for routine genetic evaluation of boars involved in crossbreeding programs ... [more ▼]

Since 2007 the Walloon Region is acquiring a new advanced genetic evaluation program for Piétrain boars. Comprehensive models for routine genetic evaluation of boars involved in crossbreeding programs, using simultaneously data recorded on crossbred progeny at central test station and data recorded on-farm on purebred or crossbred pigs, are under development. Traits evaluated include growth, carcass quality traits and feed intake. Estimated breeding values allow breeders to select the best boars according to their selection objectives. But to have comprehensive models for crossbreeding performances, more advanced modelling of non-additive and crossbreeding effects will be added to current models. Additionally potential use of genomic information will be explored. [less ▲]

Comparison of fattening performances of booars casrated or immunized against GnRF and evaluation of the vaccination efficiency

in EAAP (Ed.) Book of absracts of the 62nd annual meeing of the european federation of animal science (2011, August 29)

Effects of dietary fibres on greenhouse gas and ammonia emissions associated to gestating sows

in Cabaraux, Jean-François; Delguste, Catherine; Frippiat, thibault (Eds.) et al Proceedings of the 1st Scientific Meeting of the Faculty of Veterinary Medicine (Liège – Belgium) (2011)

Usually, gestating sows are restrictedly-fed to prevent excessive body weight gain and fat deposition. However, feed restriction causes sustained feeding motivation resulting in stereotypic behaviour and ... [more ▼]

Usually, gestating sows are restrictedly-fed to prevent excessive body weight gain and fat deposition. However, feed restriction causes sustained feeding motivation resulting in stereotypic behaviour and impairment of animal welfare. High fibre diets (HFD) are known to reduce feeding motivation without impairments of performance but the effects of HFD on emissions of pollutant gases are very few studied. Thus, a study was carried out to compare the effect of two fibre contents (standard diet (STD) with 22% of non-starch polysaccharides (NSP) vs. HFD with 44% of NSP) on emissions of ammonia (E-NH3), nitrous oxide (E-N2O), methane (E-CH4) and CO2-equivalents (E-EqCO2) associated to gestating sows. Three successive batches of 10 gestating sows were divided into 2 homogeneous groups and randomly allocated to one of two treatments: STD vs. HFD. The groups were kept separately in two identical rooms equipped with a pen divided into a lying area with slatted floor and five individual feeding stalls with permanent access. Emissions were measured by infrared photoacoustic detection. The HFD significantly decreased ENH3 (12.1 vs. 15.9 g/sow.day) but increased E-EqCO2 (0.68 vs. 0.47 kg/sow.day) in relation with an increase of E-CH4 (18.4 vs. 9.1 g/sow.day), E-N2O being not impacted by the diet, with value around 0.60 g/sow.day. So, the effects of HFD offered to gestating sows on slatted floor on environment seem conflicting with a decrease of NH3 emissions which mainly contribute to acidification of soils and waters and eutrophication, but an increase of CO2-quivalents emissions which contribute to greenhouse effect and climate change. [less ▲]

Using test station and on-farm data for the genetic evaluation of Piétrain boars used on Landrace sows for growth performance

in Journal of Animal Science (2011), 89

The aim of this study was to develop a new genetic evaluation model to estimate the genetic merit of boars for growth based on 1) performance of their crossbred progeny fattened in the test station and 2 ... [more ▼]

The aim of this study was to develop a new genetic evaluation model to estimate the genetic merit of boars for growth based on 1) performance of their crossbred progeny fattened in the test station and 2) their own performance or those of relatives from the on-farm testing system. The model was a bivariate random regression animal model with linear splines and was applied to Piétrain boars from the Walloon Region of Belgium mated with Landrace sows. Data contained 1) 12,610 BW records from the test station collected on 1,435 crossbred pigs from Piétrain boars and Landrace sows, and 2) 52,993 BW records from the on-farm testing system collected on 50,670 pigs with a breed composition of at least 40% Piétrain or Landrace. Since 2007, 56 Piétrain boars have been tested in the station. Data used to estimate variance components and breeding values were standardized for the age to take into account heterogeneity of variances and then pre-adjusted at 210 d of age to put all records on the same scale. Body weight records from the test station and from the on-farm testing system were considered as 2 different traits. The heterosis effect was modeled as fixed regression on the heterozygosity coefficient. As all test station animals were similarly crossbred, smaller variation in heterozygosity caused the sampling error of the regression estimate at 210 d to be larger in the test station than in on-farm data with estimates of 28.35 ± 14.55 kg and 9.02 ± 0.67 kg, respectively. Therefore, the most likely reason for the large differences in estimates was sampling. Heritability estimates ranged from 0.37 to 0.60 at 210 and 75 d, respectively, for test station BW and from 0.42 to 0.60 at 210 d and 175 d, respectively, for on-farm BW. Genetic correlation decreased when the age interval between records increased, and were greater between ages for test station than for on-farm data. Genetic correlations between test station and on-farm BW at the same age were high: 0.90 at 175 d and 0.85 at 210 d. For the 56 boars tested in the station, the average reliability of their EBV for ADG between 100 and 210 d was improved from 0.60 using only test station data to 0.69 using jointly test station and on-farm data. Based on these results, the new model developed was considered as a good method of detection of differences in growth potential of Piétrain boars based on test station and on-farm data. [less ▲]

Système d'évaluation génétique des verrats Piétrain en croisement en Wallonie

Diverse speeche and writing (2011)