Study protocol for a pragmatic cluster randomized controlled trial to improve dietary diversity and physical fitness among older people who live at home (the “ALAPAGE study”)

Background : Diet and physical activity are key components of healthy aging. Current interventions that promote healthy eating and physical activity among the elderly have limitations and evidence of French interventions’ effectiveness is lacking. We aim to assess (i) the effectiveness of a combined diet/physical activity intervention (the “ALAPAGE” program) on older peoples’ eating behaviors, physical activity and fitness levels, quality of life, and feelings of loneliness; (ii) the intervention’s process and (iii) its cost effectiveness. Methods : We performed a pragmatic cluster randomized controlled trial with two parallel arms (2:1 ratio) among people ≥60 years old who live at home in southeastern France. A cluster consists of 10 people participating in a “workshop” (i.e., a collective intervention conducted at a local organization). We aim to include 45 workshops randomized into two groups: the intervention group (including 30 workshops) in the ALAPAGE program; and the waiting-list control group (including 15 workshops). Participants (expected total sample size: 450) will be recruited through both local organizations’ usual practices and an innovative active recruitment strategy that targets hard-to-reach people. We developed the ALAPAGE program based on existing workshops, combining a participatory and a theory-based approach. It includes a 7-week period with weekly collective sessions supported by a dietician and/or an adapted physical activity professional, followed by a 12-week period of post-session activities without professional supervision. Primary outcomes are dietary diversity (calculated using two 24-hour diet recalls and one Food Frequency Questionnaire) and lower-limb muscle strength (assessed by the 30-second chair stand test from the Senior Fitness Test battery). Secondary outcomes include consumption frequencies of main food groups and water/hot drinks, other physical fitness measures, overall level of physical activity, quality of life, and feelings of loneliness. Outcomes are assessed before the intervention, at 6 weeks and 3 months later. The process evaluation assesses the fidelity, dose, and reach of the intervention as its causal mechanisms (quantitative and qualitative data). Discussion : This study aims to improve healthy aging while limiting social inequalities. We developed and evaluated the ALAPAGE program in partnership with major healthy aging organizations, providing a unique opportunity to expand its reach

Format adulte des vaches charolaises : variabilité génétique et relation avec la précocité de développement.

National audienc

Genetic analysis of calf health in Charolais beef cattle

The objective of this study was to investigate the factors that influence calf health and survival in Charolais cattle. Data from 2,740 calves, originating from 16 French farms and observed from birth until 30 d of age, were analyzed using models that took account of direct genetic, maternal genetic, and common environmental effects. Both direct and maternal genetic parameters were estimated for birth weight (BW), calving ease (CE), neonatal vitality (NV), survival at 30 d (Surv), and umbilical infection and diarrhea at different ages (0 to 5 d: Umb1 and Diar1; 6 to 20 d: Umb2 and Diar2; and 21 to 30 d: Umb3 and Diar3). The heritability values for direct and maternal genetic effects were, 0.026 (SE = 0.027) and 0.096 (SE = 0.042) for Surv, 0.280 (SE = 0.063) and 0.063 (SE = 0.038) for BW, 0.129 (SE = 0.041) and 0 for CE, 0.073 (SE = 0.035) and 0 for NV, 0.071 (SE = 0.038) and 0.017 (SE = 0.026) for Umb1, 0 and 0.082 (SE = 0.029) for Umb2, 0 and 0.044 (SE = 0.030) for Diar1, 0.016 (SE = 0.022) and 0.012 (SE = 0.026) for Diar2, and 0.016 (SE = 0.028) and 0 for Diar3, respectively. Significant genetic variability in beef cattle was thus revealed for five calf health traits: NV, Surv, Diar1, Umb1, and Umb2. In addition, for three traits (Surv, Diar1, and Umb2), maternal genetic effects clearly contributed more to health performance than direct genetic effects. Estimates of genetic correlation between traits varied markedly (from 0 to 1 in absolute values) depending on the traits in question, the age for a given trait, and the type (direct or maternal) of the genetic effects considered. These results suggest that not all health traits in Charolais cattle can be improved simultaneously, and breeders will therefore have to prioritize certain traits of interest in their breeding objectives. Overall, our results demonstrate the potential utility of collecting and integrating data on calf diseases, NV and survival in future beef cattle breeding programs. To ensure appropriate biological and genetic evaluations of calf health performance, it is important to accurately describe the phenotypes for diarrhea and umbilical infections (in terms of age ranges) and account for maternal genetic and common environmental effects that explain calf health performance traits. Further investigation and improved data collection are now necessary to maximize the efficiency of breeding schemes designed to simultaneously improve production and health traits

Methane and carbon dioxide emission of beef heifers in relation with growth and feed efficiency

Reducing enteric methane production and improving the feed efficiency of heifers on roughage diets are important selection objectives for sustainable beef production. The objective of the current study was to assess the relationship between different methane production and feed efficiency criteria of beef heifers fed ad libitum roughage diets. A total of 326 Charolais heifers aged 22 months were controlled in two farms and fed either a grass silage (n = 252) or a natural meadow hay (n = 74) diet. Methane (CH4) and carbon dioxide (CO2) emission rates (g/day) were measured with GreenFeed systems. The dry matter intake (DMI), average daily gain (ADG), CH4 and CO2 were measured over 8 to 12 weeks. Positive correlations were observed among body weight, DMI, ADG, CH4 and CO2. The residual feed intake (rwgDMI) was not related to CH4 or residual methane (rwiCH4). It was negatively correlated with methane yield (CH4/DMI): Rp = −0.87 and −0.83. Residual gain (rwiADG) and ADG/DMI were weakly and positively related to residual methane (rwiCH4): Rp = 0.21 on average. The ratio ADG/CO2 appeared to be a useful proxy of ADG/DMI (Rp = 0.64 and 0.97) and CH4/CO2 a proxy of methane yield (Rp = 0.24 and 0.33) for selecting low-emitting and efficient heifers

O2-1 Improving diet and physical activity in older adults living at home: protocol for the ALAPAGE cluster randomized controlled trial

International audienceBackground: Adequate nutrition and regular physical activity (PA) are key elements in healthy aging. In France, behavioural interventions promoting healthy eating and PA in older adults consist mainly in collective workshops organised by pension and health insurance funds. After analyzing pre-existing workshops, we designed the co-constructed project ALAPAGE to improve these workshops and assess their impact on diet and PA. Methods: ALAPAGE is a cluster randomized controlled trial; 60 collective workshops in southeastern France will be randomized in a 2:1 (intervention/control) ratio. We will recruit 900 autonomous older adults (? 60 years) living at home and will make specific efforts to recruit socially isolated and/or economically vulnerable people. In the intervention group, collective workshop period will include 7 sessions (1 session/week): 1 introductory, 4 diet and 2 PA (to teach principles of functional dual-task exercise focused on strength, flexibility and physical functioning). During the following 3-months, participants will be recommended to perform exercises as often as possible and will participate in post-workshop activities. The control group will first participate to other types of workshops and then to a diet and PA workshop (waiting-list design). Results: The dietary practices (using experimental economics), physical activity (battery of field test and habitual PA), quality of life, and cost-effectiveness will be assessed at the first and last session, and 3 months later.Conclusion: Results will guide decision-makers to organize actions and their dissemination. Transferability to other regions will be facilitated by the fact that key stakeholders involved in ALAPAGE belong to structured national networks

Relations génétiques entre les capacités d’ingestion de taurillons, bœufs, génisses et vaches

National audienceFeed intake capacity of forages is an essential ability of beef cows that have to exploit grass land, with summer grazing and stored forage feeding in winter. However a reduction of consumption above production requirements will be highly beneficial since cow feeding costs represent a large part of herd maintenance costs. Presently in France, selection of beef traits in beef breeds aims at improving muscle growth and feed efficiency in feed lots. Is this selection wise to maintain the forage intake capacity of cows and can it help in selecting cows that are thrifty in feed utilisation, while this selection is performed in station where differences in feed intake are minimized by energy content of the diet ? Basic responses are presented with the estimated genetic parameters of the following traits: weights, daily feed intake and residual feed intake measured in different types of animals procreated and controlled in the INRA experimental centre of Bourges: 1408 young bulls, 212 steers, 498 heifers and 472 culled cows, progeny of 60 sires. Residual feed intake is the intake adjusted for live weight and variation of weight during the test. Feed intake and residual feed intake are moderately heritable in males and slightly heritable in females. Genetic correlations between feed intake and weight and between feed intake and residual feed intake are high whatever the animal type. Finally our study shows that selection to increase growth and reduce residual feed intake of young growing bulls is possible. Correlatively this selection should improve weight and feed intake of cows without modifying residual feed intake however.La capacité d’ingestion de fourrages grossiers représente une aptitude primordiale de la vache allaitante qui exploite prioritairement des surfaces herbagères (pâturage en été, fourrages conservés en hiver). Toutefois, les coûts alimentaires représentant une grande part des frais d’entretien du troupeau, il serait souhaitable de pouvoir sélectionner des vaches économes qui limitent leur consommation au-delà de leurs strictes besoins de production. Actuellement la sélection des taureaux d’insémination des races à viande spécialisées vise prioritairement à améliorer la croissance musculaire et l’efficacité alimentaire dans un système d’engraissement intensif. Cette sélection est elle compatible avec le maintien d’une capacité d’ingestion suffisante de fourrages grossiers par les vaches et permet-elle de sélectionner des vaches plus économes, alors que cette sélection se pratique en station où les différences de capacités d’ingestion sont minimisées de par la concentration énergétique des rations ? Des éléments de réponse sont apportés avec l’estimation des paramètres génétiques des caractères suivants : croissance, consommation alimentaire et consommation résiduelle, la consommation résiduelle nous permettant de comparer les niveaux d’ingestion des animaux corrigés pour leurs poids et variations de poids, ces caractères ayant été mesurés sur différents types d’animaux procréés et contrôlés sur le domaine INRA de Bourges : 1408 taurillons, 212 bouvillons, 498 génisses et 472 vaches, issus pour l’essentiel de 60 pères. Notre étude montre que les consommations moyennes et résiduelles sont moyennement héritables chez les mâles et faiblement héritables chez les femelles. Les corrélations génétiques entre consommations moyennes et poids et entre consommations moyennes et résiduelles sont élevées quel que soit le type de production considéré. Notre étude montre également qu’une sélection visant à augmenter la croissance des jeunes mâles tout en réduisant leur consommation résiduelle est possible et qu’une telle sélection devrait corrélativement permettre un accroissement du poids et des quantités de fourrage ingéré chez les vaches sans pour autant modifier leur consommation résiduelle

Genomic-wide scan of ovulation rates in beef heifers and cows

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Genetic control of multiple births in low ovulating mammalian species

In mammals, litter size is a highly variable trait. Some species such as humans or cattle are monotocous, with one or sometimes two newborns per birth, whereas others, the polytocous species such as mice or pigs, are highly prolific and often produce a dozen newborns at each farrowing. In monotocous species, however, two or three newborns per birth may sometime be unwanted. In more polytocous species such as sheep or pigs, litter size is studied in order to increase livestock prolificacy. By contrast, twinning rates in humans or cattle may increase birth difficulties and health problems in the newborns. In this context, the aim of our review was to provide a clearer understanding of the genetic and physiological factors that control multiple births in low-ovulating mammalian species, with particular focus on three species: sheep, cattle, and humans, where knowledge of the ovulation rate in one may enlighten findings in the others. This article therefore reviews the phenotypic and genetic variability observed with respect to ovulation and twinning rates. It then presents the QTL and major genes that have been identified in each species. Finally, we draw a picture of the diversity of the physiological mechanisms underlying multiple ovulation. Although several major genes have been discovered in sheep, QTL detection methods in humans or cattle have suggested that the determinism of litter size is complex and probably involves several genes in order to explain variations in the number of ovulations

Genetic control of ovulation rate in Maine-Anjou cattle

International audienc