Assessing the sustainability of pig production in Wallonia: development of a simulation tool

peer reviewedGarantir la durabilité d’une filière de production implique d’évaluer son impact sur les trois dimensions du développement durable : (1) maîtrise des impacts sur l’environnement, (2) viabilité économique, (3) attentes sociétales des éleveurs, des citoyens et des consommateurs. Cette recherche s’inscrit dans le cadre de la révision, par les autorités publiques de Wallonie (Belgique), des critères minimaux permettant la reconnaissance de la qualité différenciée axés sur les 3 piliers de la durabilité. Elle consiste à développer un outil informatique de modélisation mathématique du fonctionnement technico-environnemental de la production porcine et de ses impacts socio-économiques. Le programme est développé dans Matlab. Le modèle s’articule autour des différentes composantes des systèmes de production selon le paradigme orienté-objet. Les nouveaux critères de différenciation qui définiront de nouveaux labels axés sur des attributs de durabilité en constituent les variables motrices : taille de l’exploitation, origine des aliments et des matières premières, logement, indépendance énergétique, effluents, etc. Les impacts sont relevés à chaque étape de production jusqu’à la sortie du porc sur pied de la ferme selon la norme « Analyse de Cycle de Vie » (ACV). L’évaluation environnementale utilise des modèles mécanistiques de flux de composés chimiques, convertis en indicateurs ACV. L’analyse de la dimension sociale s’appuie sur une base de données intégrée, comprenant le temps de travail. Enfin, un modèle économique attestera du dernier volet. L’outil finalisé permettra de prédire les conséquences de choix opérationnels liés aux critères de qualité différenciée au niveau d’une exploitation.Création d'un outil d'évaluation de la durabilité des productions animales en Région wallonne: comparaison entre productions porcines conventionnelles et de qualité différencié

Modeling the Biomass Production of Grasslands of Wallonia According to their Functional Type

Permanent grasslands are complex ecosystems which respond with a great variability - in terms of specific richness - to soil type and management strategies. Modelling is a valuable tool to explore these relationships. Our work consisted in adapting the Moorepark St Gilles grass growth model (MoSt GG) designed to model Lolium perenne plant functional type (PFT) pastures (PFT A) to a different PFT (Dactylis glomerata, PFT B) through literature-based parametrization. The model was evaluated under Walloon (Belgium) conditions using growth trials from 2014 to 2018 in two sites with contrasting pedo-climatic conditions. Three to five cuts were performed over the course of the growing seasons depending on the rainfall yielding a total of 20 and 25 biomass measurements (kg of DM per ha), for PFT A and B respectively. No site effects were observed in the performance of the model. The relative root mean square error (RRMSE), normalized deviation (ND) and model efficiency (EF) across all cuts, sites and PFTs were 33%, 3% and 68% respectively. PFT B was better simulated than A for the criteria RRMSE (33% vs 33%), ND (4% vs. 9%), and EF (75% vs. 54%). Although this first evaluation was satisfactory, a complementary parametrization for additional pedoclimatic conditions and PFTs is called for to use the model under the diversity of Walloon condition

A Rapid Estimation of Nitrogen Bound to Neutral Detergent Fibre in Forages by Near Infrared Reflectance Spectroscopy

Near infrared reflectance spectroscopy (NIRS) is widely used as a rapid method for the evaluation of the chemical composition or the nutritive value of foodstuffs (Givens et al., 1997). The determination of the neutral detergent fibre (NDF) bound N (NDF-N), which is highly variable in forages (Shayo & Udén, 1999), is expensive. The purpose of this study was to test the use of NIRS in the prediction of NDF-N in various forages

Varietal effects of barley carbohydrate composition on digestibility, fermentability and microbial ecophysiology in an in vitro model of the pig gastrointestinal tract.

Carbohydrate (CHO) composition can vary markedly between barley varieties. Their influence on digestibility, intestinal fermentation and microbiota in pigs was studied in vitro. Ten hulless (HLB) and 6 hulled barleys (HB) differing in B-glucan, non-starch polysaccharides (NSP), starch content, and amylose/amylopectin ratio, were hydrolyzed enzymatically and subsequently fermented for 72h. CHO fermentation kinetics were modeled; microbial composition and short-chain fatty acid (SCFA) production were analyzed. In HLB, in vitro DM digestibility was positively correlated to starch and amylopectin content and CP digestibility to amylopectin (P<0.05), whereas both were negatively correlated to insoluble NSP (P<0.05). Rate of fermentation was different (P<0.01) between barley types but not correlated to the CHO composition. However, high B-glucan contents induced faster fermentation (P<0.05, HLB; P<0.10, HB). SCFA molar ratios after fermentation of HLB were higher in propionate and branchedchain fatty acids and lower in acetate compared to HB (P<0.01). With HLB, amylose content was positively correlated to butyrate production and negatively to propionate, which was positively correlated to soluble NSP content (P<0.01). In HB, no correlation between SCFA production and the carbohydrate composition was found. TRFLP analysis revealed that Bacteroides and members of Clostridium cluster XIVa were differentially affected in HLB compared to HB as well as by the type and source of CHO. Microbial profiles were also correlated (P<0.05) to SCFA and fermentation parameters but response differed significantly between HB and HLB. The strongest correlation between CHO structure, microbial abundance and fermentation parameters was evident in HLB. Hulless barleys may offer the greatest opportunity to improve gut health in pigs

Hedges and Woody Strips Browsing by Cattle on Pasture in Wallonia, Belgium

Shrub and tree forages are commonly used in animal production in many regions of the world. Nonetheless, in Western Europe, and especially in Wallonia in Belgium, hedges and woody strips have disappeared from the agricultural landscape over the past 60 years. Browse species are usually rich in plant secondary compounds such as tannins whose benefits on CH4 production and intestinal parasitism have been highlighted (Ramírez-Restrepo et al. 2010). Currently, agri-environmental measures taken by the Walloon government promote hedges and woody strips in pastures, raising the interest in browse species functionalities in ruminant production. This study aimed at: (1) determining the influence of the access to a hedge on the behaviour of cattle on pasture; and (2) evaluating the fermentability by rumen microbes of foliage of woody species promoted in the Walloon landscape

Impact of high-wheat bran diet on sows’ microbiota, performances and progeny’s growth and health

Finding alternatives to antimicrobial growth promoters is part of the goal of improving sustainability in pig production. Dietary fibres are considered as health-promoting substances acting on pigs’ microbiota. This study aimed to investigate whether the enrichment of sows’ diet with high levels of wheat bran (WB) could impact the performances of sows and piglets’ health. Seven sows were fed a control diet (CON) and 8 sows a WB diet from day 43 of gestation (WB 240 g/kg DM) until the end of the lactation period (WB 140 g/kg DM). Diets were formulated to be iso-energetic and iso-nitrogenous by changing the proportions of some ingredients. Faeces were sampled at different time points (before treatment, during treatment: in gestation and lactation) to determine microbiota composition (sequencing with Illumina MiSeq). Milk was sampled weekly to determine lactose, fat and protein concentration by mid-infrared technology and IgA and IgG contents by ELISA. Before weaning (d26-27), piglets were euthanized, intestinal contents and tissues sampled for further analyses. Zootechnical performances of sows and piglets were recorded. Statistical analyses were performed using the SAS MIXED procedure and repeated measurements. Treatment never impacted piglets’ weight (P=0.51). Sows’ ingestion during the lactation period was comparable between both treatments until the last 4 days of lactation where the percentage of target ingestion was significantly (P<0.001) lower for the WB (66%) compared to the CON group (89%). No effect on sows’ backfat and weight changes was observed. An increased abundance of Lactobacillus spp. in feces of the WB group was observed in gestation before and after diet change (8.8% vs 15.1% of total bacteria). However, for the overall genera changes between treatments, it only seems to occur for minor groups of bacteria. Milk protein, fat, IgG and IgA were not affected by treatment, but a time-effect (P<0.001) was observed while treatment impacted (P<0.05) lactose content. In conclusion, sows’ performances were not affected by the high WB diet and more research on the piglets’ samples is foreseen

Recent Advances on Early Detection of Heat Strain in Dairy Cows Using Animal-Based Indicators: A Review

peer reviewedIn pursuit of precision livestock farming, the real-time measurement for heat strain-related data has been more and more valued. Efforts have been made recently to use more sensitive physiological indicators with the hope to better inform decision-making in heat abatement in dairy farms. To get an insight into the early detection of heat strain in dairy cows, the present review focuses on the recent efforts developing early detection methods of heat strain in dairy cows based on body temperatures and respiratory dynamics. For every candidate animal-based indicator, state-of-the-art measurement methods and existing thresholds were summarized. Body surface temperature and respiration rate were concluded to be the best early indicators of heat strain due to their high feasibility of measurement and sensitivity to heat stress. Future studies should customize heat strain thresholds according to different internal and external factors that have an impact on the sensitivity to heat stress. Wearable devices are most promising to achieve real-time measurement in practical dairy farms. Combined with internet of things technologies, a comprehensive strategy based on both animal- and environment-based indicators is expected to increase the precision of early detection of heat strain in dairy cows

Intra‐cultivar potential of Desmanthus spp. as a greenhouse gas mitigation strategy for tropical livestock pastoral systems

Improved agricultural efficiency and reduction in the impacts of tropical livestock farming on habitat degradation require global approaches that enhance ruminant farming functionality in terms of feed use efficiency, emissions and food security. This study evaluated the in vitro mitigation potential of the prostrate to erect, herbaceous Desmanthus spp. pasture legume adapted to semiarid clay soil land types in northern Australia. D. bicornutus, D. leptophyllus and D.virgatus were seasonally harvested from commercial plots by Agrimix Pty. Ltd. Samples of the legumes and the control Rhodes grass (Chloris gayana) using ruminal fluid from grazing Brahman (Bos indicus) steers were incubated in vitro (Ankom RF1 Technology) for 24, 48 and 72 h. Overall, the in vitro organic matter degradability (OMD) and methane production between Desmanthus species differed (P < 0.001). Compared to the control (0.656 ± 0.027 proportion of total OM) at 48 h of incubation, D. leptophyllus showed lower OMD (0.479 ± 0.016), while D. bicornutus (0.688 ± 0.016) and D. virgatus (0.619 ± 0.015) were different from each other, but similar to the control. Methane production (ml/g OM) was 15.7 ± 1.54, 3.7 ± 0.89, 12.0 ± 0.95 and 11.7 ± 0.95, respectively. It is suggested that the impact of these attributes may benefit household farmers in developing economies to expand productivity, improve livelihoods and meet the growing food consumption. Further analyses of the intra‐cultivar characteristics of Desmanthus spp. will complement the design of sustainable and efficient interventions across tropical pastoral feeding systems, with a particular emphasis on large‐scale grazing operations