Réduire les rejets azotés des porcs en croissance par un ajustement dynamique des apports en acides aminés au besoin et une diminution de la teneur en matières azotées totales de l'aliment

A test was performed with 96 growing pigs to implement precision feeding (PF) of restricted-fed growing pigs to characterise growth performance and N output using a PF system developed in the Feed-a-Gene project (H2020, no. 633531) compared to a 2-phase strategy (2P). A decision support tool was used to manage data (mainly individual and daily body weight (BW) measured with an automatic scale), to forecast performance on the following day, to assess corresponding amino acid requirements, and to adapt the quality of the diet delivered on the next day through the proportion of two diets used in a blend. Both diets were formulated to 9.75 MJ net energy (NE)/kg, with contrasting concentrations of digestible lysine and crude protein (A: 1.0 g lysine/MJ NE and 16.6% N x 6.25, B: 0.5 g/MJ NE and 10.9% N x 6.25). Forecasting BW and BW gain for PF pigs was interrupted for 2 weeks due to a problem with an electronic device for 2 consecutive days; it identified a problem of robustness in how forecasting methods were applied. A solution was found and applied to improve the entire system. However, no significant differences were observed between strategies for growth rate (2P: 722 vs PF: 716 g/d, P = 0.62), feed conversion ratio (2.64 vs 2.70, P = 0.063) or carcass leanness (62.0 vs 61.4 units, P = 0.18). The crude protein content of the blend provided to 2P during the growing and finishing phases was 15.8% and 13.4%, respectively. With this new 2P diet management, N output can potentially be reduced by 10% compared to a 2P with standard diets (16.0% and 15.0% N x 6.25). Despite the technical problem, which might have minimised the difference in N intake betweenstrategies, the PF contributed an additional decrease of 6%

Modeling of the transient interstitial diffusion of implanted atoms during low-temperature annealing of silicon substrates

It has been shown that many of the phenomena related to the formation of "tails" in the low-concentration region of ion-implanted impurity distribution are due to the anomalous diffusion of nonequilibrium impurity interstitials. These phenomena include boron implantation in preamorphized silicon, a "hot" implantation of indium ions, annealing of ion-implanted layers et cetera. In particular, to verify this microscopic mechanism, a simulation of boron redistribution during low-temperature annealing of ion-implanted layers has been carried out under different conditions of transient enhanced diffusion suppression. Due to the good agreement with the experimental data, the values of the average migration length of nonequilibrium impurity interstitials have been obtained. It has been shown that for boron implanted into a silicon layer preamorphized by germanium ions the average migration length of impurity interstitials at the annealing temperature of 800 Celsius degrees be reduced from 11 nm to approximately 6 nm due to additional implantation of nitrogen. The further shortening of the average migration length is observed if the processing temperature is reduced to 750 Celsius degrees. It is also found that for implantation of BF2 ions into silicon crystal, the value of the average migration length of boron interstitials is equal to 7.2 nm for thermal treatment at a temperature of 800 Celsius degrees.Comment: 10 pages, 6 figures, RevTe

Life story of outrigger canoeing coach: challenges in herent to establishing and developing the professional field of practice

O objetivo do presente estudo foi descrever as situações episódicas da trajetória de vida de um treinador de canoagem havaiana no seu desenvolvimento e no estabelecimento do seu campo de atuação. Foi realizada uma entrevista semiestruturada baseada em incidentes críticos. A análise dos dados se deu pela espiral de Creswell e os resultados foram apresentados em vinhetas do tipo retrato. Identificou-se sete contextos com os episódios marcantes da sua trajetória, divididos nas vinhetas: infância, inserção na canoagem havaiana, trilhando por um novo caminho, a estruturação do clube, consequências do crescimento: positivas e negativas, busca constante por conhecimento e dias atuais. O desenvolvimento do treinador pareceu se dar pelas experiências ao longo da vida, iniciando por aquelas vivenciadas na infância. O curso de Educação Física, por sua vez, contribuiu para aprendizagem de conhecimentos interpessoais, necessários ao desenvolvimento da relação treinador-atleta. Já o estabelecimento do campo de atuação se deu por iniciativa própria, uma vez que a canoagem havaiana era emergente no Brasil e ainda não possuía um campo estabelecido.The aim of this study was to describe episodic situations in the lifestory of an outrigger canoeing coach for his own development and for the establishment of his professional field of practice. A semi-structured interview was conducted based on critical incidents. Data was analyzed using Creswell’s spiral and the results were presented in portrait vignettes. Seven contexts with remarkable episodes of hisstory were identified, and divided into the following vignettes: childhood, insertion into outrigger canoeing, walking in a new way, structuring the club, positive and negative consequences of growth, constant search for knowledge, and current days. The coach's development seemed to take place through life-long experiences; beginning with those lived during childhood. Due to the emergente nature of outrigger canoeing in Brazil, establishing the professional field of practice was the coach’s own initiative.Facultad de Humanidades y Ciencias de la Educació

Precision feeding with a decision support tool dealing with daily and individual pigs' body weight

Nutritionists, feed companies and equipment manufacturers look for solutions that help farmers to improve sustainability of pig production. Based on experimental results obtained in silico or in vivo, a better adequacy between amino acid supplies and requirements increases feed efficiency and farmer’s income and reduces the environmental impact of growing pigs, highlighting the interest for precision feeding. Data are collected to characterize daily animal traits (e.g. body weight, BW) and their variation from one day to another (e.g. growth rate, ΔBW). They are used to determine the requirement for maintenance and growth on the next day, respectively. Therefore, adequacy between requirements and supplies depends on these predicted BW and ΔBW. The double exponential smoothing (Holt-Winters) method with a smoothing parameter α=0.6 (HW0.6), presents a low sensitivity to the number of latest values used to forecast BW. It seems to allow for a secured prediction of BW soon after the beginning of the growing phase (at least after 4 days). A group of pigs was used in restricted feeding conditions to compare results obtained either with a 2-phase feeding strategy, considered as the control treatment, or a precision feeding strategy based on BW forecasting with the HW0.6 method. Pigs allocated to both treatments were group-housed in the same pen, equipped with the decision support system built in the Feed-a-Gene project to manage the data, to determine in real-time the corresponding nutritional requirements, and to adapt the feed characteristics provided to each pig through the blend of two diets (9.75 MJ net energy/kg, 0.5 or 1.0 g of digestible lysine per MJ). Available results from 24 pigs per treatment indicate that overall average growth performance were not influenced by the feeding strategy (P>0.58 for both average daily gain and feed conversion ratio) but digestible lysine intake was reduced by 6% (1,774 vs 1,879 g, P<0.01) and N output by 7% (P<0.01) with precision feeding. Results will be completed by a second group using the same treatments. This study is part of the Feed-a-Gene project and received funding from the European Union’s H2020 program under grant agreement no. 633531

Assessment of the dynamic growth of the fattening pigs from body weight measured daily and automatically to elaborate precision feeding strategies

Growing pigs are often fed below ad libitum to increase their feed efficiency and carcass leanness. When energy supply is under control, precision feeding is implemented through the amino acids (AA). As the AA requirement depends on the body weight (BW) for the maintenance part and on its daily variation (ΔBW) for the growth part, the adequacy between requirements and supplies on day D+1 depends on the adequacy of predicted BWD+1 and ΔBWD+1. Data sets from four trials were used to forecast BW from time series analyses based either on multivariate adaptive regression splines (MARS) or double exponential smoothing (HWα) methods using the k latest data (8, 14 or 20). Pigs (n = 117) were group-housed and restrictively fed, and their BW was recorded daily and individually with an automatic scale (n = 11 736). With HW0.6, the RMSEP of BWD+1 was the smallest one (1.21 kg) and not influenced by k. Linear regression on the l latest forecasted BW was used to assess ΔBWD+1. At the beginning of the trial, ΔBWD+1 was more difficult to predict from BW forecasted with MARS than with HW0.6. Descriptive statistics of individual variation of ΔBWD+1 based on MARS and HW0.6 were comparable with k = l = 20 only after removal of the first 19 days. Compared to other methods studied, the method HW0.6 seems to be the best compromise to forecast BWD+1 and ΔBWD+1 of restrictively fed pigs

SmartPharm - Développement d’une pharmacie connectée pour les élevages porcins

The fight against antibiotic resistance is at the heart of the concerns of the pig industry and this requires perfect management of medication by breeders. To do this, dynamic and real-time monitoring of the various treatments carried out, compared to references, would make it possible to be more responsive and to continue the reduction. The breeding registers are in papers, so they are difficult to consult, that is why IFIP launched the SmartPharm project, in collaboration with the company Asserva. Using an application and a software combined, the SmartPharm solution makes it possible to record in real time the treatments carried out on the farm and to obtain up-to-date pharmacy and animal inventory monitoring. The information is gathered in a local and connected database to avoid duplicates and internet connection problems encountered in farms. The data is then presented to the breeder and his veterinarian in various dashboards detailed by physiological stage, therapeutic class, and reason, and compared to the GVet references, this allowing a better understanding of the use of treatments in the breeding for improve practices and continue to reduce the use of antibiotics.La lutte contre l’antibiorésistance est au cœur des préoccupations de la filière porcine et passe par uneparfaite maîtrise de la médication par les éleveurs. Un suivi dynamique et en direct des différentstraitements réalisés, comparé à des références, permettrait d’être plus réactif et de poursuivre la baisse entamée. Aujourd’hui, les registres d’élevage sont sous format papier et difficilement consultable, c’est pourquoi l’IFIP a lancé le projet SmartPharm, en collaboration avec la société Asserva. Sous forme d’une application et d’un logiciel, la solution SmartPharm permet de saisir en temps réel lestraitements réalisés sur un élevage et d’obtenir un suivi à jour de la pharmacie et des stocks animaux. Les informations sont regroupées dans une base de données locale et connectée pour éviter les doublons et les soucis de connexion internet rencontrés dans les élevages. Les données sont ensuite présentées à l’éleveur et à son vétérinaire dans différents tableaux de bord détaillés par stade physiologique, par classe thérapeutique, par motif, et comparées aux références GVet. Ces comparaisons permettent de mieux appréhender l’utilisation des traitements dans l’élevage, d’améliorer les pratiques et de continuer la réduction de l’usage des antibiotiques

Accelerometer technology to perform precision feeding of pregnant sows and follow their health status

Two trials were conducted at experimental stations of IFIP, located in Romillé (France, Trial 1), and INRA, located in Saint Gilles (France, Trial 2), on pregnant sows equipped with individual ear tag accelerometers to record their activity level: duration of lying, standing and moving sequences. The first trial involved 72 sows penned on a slatted floor in a dynamic group with connected drinkers and automatic feeders, whereas the second trial was carried out on 4 small groups of 6 sows penned on a concrete floor with straw and fed in individual stalls. Firstly, an algorithm was built from video recordings of 24 sows on the slatted floor (2 x 2 h sequences per sow, 96 h). Secondly, the accuracy of the algorithm was assessed by recording and sequencing 96 h and 109 h, respectively, on the slatted floor and concrete floor with straw. The respective sensitivities of the lying, standing and moving behaviours on the slatted floor were 94.4%, 66.9% and 68.4%. With straw, lower sensitivity values were found: 93.65% for lying, 68.35% for standing and 38.83% for moving, linked to more investigative behaviours using the head. The final step was to use these data to improve the feeding practices of pregnant sows, taking their activity level into account. The strong inter- and intra-individual variability shown in the physical activity is a limiting factor for detection of health problems, such as lameness, through the accelerometers. Thus we need additional information, especially the behaviour data generated by identified drinkers and automatic feeders

Premiers résultats issus d'une station d'alimentation innovante pour la mise en œuvre de l'alimentation de précision des porcs en croissance élevés en groupe et alimentés de façon rationnée

A feeder prototype has been developed by IFIP in association with an equipment manufacturer to perform precision feeding for 96 group‐housed growing pigs, each equipped with a RFID (Radio Frequency IDentification) ear tag. It consists in five automatic feeders (AF), one weighing‐sorting station (WS), and three areas. The WS station is placed on force sensors and allows for weighing pigs individually, with a 0.1 kg accuracy, and sorting them towards (1) the AF (pigs whose daily cumulated feed intake is presently below the daily allowance), (2) a pen for specific care or departure for the slaughterhouse (after selection by the farmer), (3) the original pen for the other cases. In case 1, the pig enters an AF, both back and front doors close automatically. Its ear RFID tag is recognized by an antenna, and successive doses of feed fall into the trough. Each AF can deliver (min 30 g) and mix two diets, and is connected to a computer that calculates the daily dietary allowances per pig, based on time, body weight (BW) and feeding strategy. In this first trial, all pigs were restricted and two feeding strategies were designed (2‐ vs 9‐ phase strategy) based on the same evolution of amino acid requirements with BW for all pigs. Taking into account pigs not adapted to the system after 9 days (n = 4), accidents (n = 2), health issues (n = 5) and those which failed to consume their feed allowance on more than 4 days (n = 14), data from 71 pigs were available at the end of the fattening period