76 research outputs found
Livestock and Local Development: Going to a New Humananimal Relationship
Along the past ten years, the French National Agency for Research (ANR) has financed projects regarding livestock. Results of five projects were gathered to understand the long-term livestock trends. At the end of the 19th century, animal breeding was oriented towards the production of goods to meet the local, regional, national and global demand, according to the zone. The market gradually became the key-factor to norm both production and consumption. It is now integrating environmental norms and is starting to invest in the social domain. However, this economical vision of animal production does not take into account the other functions of livestock, from âfarm forkâ to âtable forkâ. So, in parallel to the multi-functionality of livestock at the farm level, which is mentioned by several authors, livestock has a significant role at the local scale. Furthermore, in the past four decades, animal production sector has known several serious scandals with severe consequences in human health. At the same time, the FAO scoop in 2006 about the significant environmental impact of animal breeding has chocked a large part of the human society. Hence, in parallel to the discredit of animal production towards the consumers, these successive crises have led a part of the local and global society to question the human-animal relationship. In this way, a large part of the urban population with no contact with the rural world, would easily believe in animal welfare, and break the supply chain leading to the slaughterhouse. And to confirm this trend, research institutes are already seeking alternatives to meat and animal proteins. Consequently, maybe it is time now to think imagine other farming systems based on other human-animal relationships and other environment-society interactions; and perhaps to establish an adequate set of policies to strengthen this perspective
Ontogeny of the receptor for polymeric immunoglobulins in rat hepatocytes.
Based on in vitro experiments measuring daily secretion rates in the culture media of rat hepatocytes and in vivo experiments using pulse labeling of intracellular precursors, the present study examines the ontogenic expression of the polymeric immunoglobulin receptor and secretory component by hepatocytes during growth. Our data indicate that hepatocytes from infant and suckling rats (day 5, 15) cultured in serum-free and hormone-free conditions only secreted trace amounts of secretory component. Beginning on day 20, basal secretion rate showed a marked upsurge with a 10-fold increase by day 35. The addition of dexamethasone (10(-7) mol/L) to the culture media enhanced by 2.5-fold the basal secretion of secretory component by hepatocytes from 20-, 25-, and 35-day-old rats, while addition of insulin to the media had no effect. The response to dexamethasone was dose-dependent (10(-5), 10(-6), 10(-7) mol/L) and specific. In vivo pulse labeling of receptor precursors in hepatocytes from 40-day-old rats allowed the identification of three intracellular forms: a 105-kilodalton peptide and a 116-120-kilodalton mature doublet. In 13-day-old rats, three immature precursors were detected: a 105-kilodalton peptide and a high molecular weight doublet of 185-190 kilodaltons. Sucklings (13 days) treated with corticosterone showed a pattern of precursors similar to controls. These findings support the following conclusions: (a) hepatocytes from infant and suckling rats synthesize and process immature receptor precursors whose expression is unaffected by corticosterone treatment, and (b) active secretion of secretory component is initiated at weaning independently from humoral and hormonal factors while the magnitude of its production by the liver is under the control of glucocorticoids
Ontogeny of secretory component in rat liver.
The ontogeny of the expression of secretory component (SC), the receptor for transepithelial transport of polymeric immunoglobulins, in the rat liver was assessed by measuring the SC concentration in liver homogenates of rats killed from birth to 60 days of age, and by quantifying the daily SC secretion of in vitro cultured hepatocytes isolated from rats similarly killed from 2 days before birth to 60 days of age. With both methodologies, only very small amounts of SC were produced by the rat liver up to 20 days of age, whereafter expression of SC markedly increased. The development of SC production in the rat liver was co-ordinate with that previously reported in the rat small intestine, preceding the appearance of large numbers of intestinal IgA plasmacytes. These data further emphasize the importance of the liver contribution, via the bile, to the intestinal secretory IgA system of the rat
Mathematical homogenization in the modelling of digestion in the small intestine
27Digestion in the small intestine is the result of complex mechanical and biological phenomena which can be modelled at diff erent scales. In a previous article, we introduced a system of ordinary diff erential equations for describing the transport and degradation-absorption processes during the digestion. The present article sustains this simplifi ed model by showing that it can be seen as a macroscopic version of more realistic models including biological phenomena at lower scales. In other words, our simpli ed model can be considered as a limit of more realistic ones by averaging-homogenization methods on biological processes representation
AVIBIO : une methode et un outil pour évaluer la durabilité des filiÚres avicoles biologiques
The French organic poultry sector is facing new challenges relating to contexts at different geographical scales: global, European and national, including specificities of each production region. In order to evaluate what is required to meet the increasing demand for organic poultry, while moving towards sustainable production, a method and a tool to assess sustainability at the production chain scale was carried out within the framework AVIBIO project. Four regions were studied: Bretagne and RhĂŽne-Alpes for eggs, Pays de la Loire and Aquitaine for chickens. A participative approach was undertaken in order to promote exchange between the various players who are involved directly or indirectly in the production chain (production organizations, farmers, professional unions, researchers, local authorities, consumers, etc.). For each sustainability component (economic, environmental and social), indicators were fixed based on criteria which refer to the principles corresponding to the stakeholders' representations of sustainable development. A scoring scale was attributed to each indicator: high scores corresponding to the objectives being met. Scores were added per criteria and principle for each component. For the four regions, the final evaluation highlighted five ways of improvement and serves as a decision-making tool for the different stakeholders. The evaluating tool connected with AVIBIO was implemented through both an ExcelÂź file and a User's Guide, each indicator being documented. The tool and guide are downloadable from the web page of AVIBIO within the website of RMT DĂ©vAB (www.devab.org/AVIBI
Digestion Modelling in the Small Intestine: Impact of Dietary Fibre
In this work, we continue the modelling of the digestion in the small
intestine, started in a previous article, by investigating the effects of
dietary fibre. We recall that this model aims at taking into account the three
main phenomena of the digestion, namely the transit of the bolus, the
degradation of feedstuffs and the absorption through the intestinal wall. In
order to study the role of dietary fibre on digestion, we model their two
principal physiochemical characteristics which interact with the function of
the small intestine, i.e. viscosity and water holding capacity. This leads us
to consider some features of digestion which have not been taken into account
previously, in particular the interrelationship between the evolution of dry
matter and water in the bolus. The numerical results are in agreement with the
positive effect of insoluble dietary fibre on the velocity of bolus along the
small intestine and on its degradation. These results highlight the negative
effect of soluble dietary fibre on digestion. Although, this model is generic
and contains a large number of parameters, to our knowledge, it is among the
first qualitative dynamical modelling of fibre influence on intestinal
digestion
A meta-analysis on the potential utilization of millet, sorghum and cottonseed meal in broiler feeding
A meta-analysis was performed to investigate birdâs response on some selected alternative feed ingredients: millet, sorghum and cottonseed meal. The database used contained 186 treatments from 25 different experiments published from 1990 to 2013. A 1-way ANOVA was performed todetermine the difference induced by each ingredient on average daily feed intake, body weight gain and feed conversion ratio, compared to control diets. Besides, mixed effects models were developed to test the impact of the level of substitution on all parameters during starter and growing phases. Results indicated an effect of the type of feed ingredient on feed intake and growth performance with better efficiency obtained in millet. No linear relationship was established between level of substitution and variables of interest for all ingredients ( ). Additionally, the root mean square error (RMSE) determined for each subset of data demonstrated that observations of this study are practically predictable. Therefore, it is in perspective of this work to predict birdâs response to those ingredients nutrients supply. This meta-analytic approach provides significant quantitative knowledge to utilize those ingredients at different levels without any detrimental effect in broilers. Regarding the anti-nutritional factorscontent of some of these ingredients, it would be interesting to further suggest improvementsleading to an increasing utilization of these alternative feedstuffs in poultry
Inclusion of sorghum, millet and cottonseed meal in broiler diets: a meta-analysis of effects on performance
A meta-analysis was conducted (i) to evaluate broiler response to partial or total substitution of corn by sorghum and millet and (ii) to determine the effect of soybean meal replacement by cottonseed meal in broiler diet. The database included 190 treatments from 29 experiments published from 1990 to 2013. Bird responses to an experimental diet were calculated relative to the control (ExperimentalâControl), and were submitted to mixed-effect models. Results showed that diets containing millet led to similar performance as the corn-based ones for all parameters, whereas sorghum-based diets decreased growth performance. No major effect of the level of substitution was observed with millet or cottonseed meal. No effect of the level of substitution of sorghum on feed intake was found; however, growth performance decreased when the level of substitution of corn by sorghum increased. Cottonseed meal was substituted to soybean meal up to 40% and found to increase feed intake while reducing growth performance. Young birds were not more sensitive to these ingredients than older birds since there was no negative effect of these ingredients on performance in the starter phase. Results obtained for sorghum pointed out the necessity to find technological improvements that will increase the utilization of these feedstuffs in broiler diet. An additional work is scheduled to validate these statistical results in vivo and to evaluate the interactions induced with the simultaneous inclusions of sorghum, millet and cottonseed meal in broiler feedin
ULNAR ARTERY OCCLUSION EVALUATED BY POWER DOPPLER ULTRASONOGRAPHY IS ASSOCIATED WITH ACRO-OSTEOLYSIS IN SYSTEMIC SCLEROSIS
International audienceAnnual European Congress of Rheumatology (EULAR
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