Utilisation du lin en vue de l'enrichissement du lait en acides gras.

Utilisation du lin en vue de l'enrichissement du lait en acides gras

La lactoferrine et le système lactoperoxydase, des substances naturelles pour remplacer les antibiotiques en production animale.

La lactoferrine et le système lactoperoxydase, des substances naturelles pour remplacer les antibiotiques en production animale

Soil-applied selenium effects on tissue selenium concentrations in cultivated and adventitious grassland and pasture plant species

According to international nutritional standards, plant selenium (Se) concentrations in Belgium are too low. To correct this situation, adding Se in fertilizers for pastures and grasslands is suggested, similar to activities in Finland. However, there is a lack of data on meadow plant species' ability to absorb Se. Therefore, a pot experiment was initiated using 24 meadow plant species cultivated on a Belgian cambisol receiving standard fertilizer treatment, with or without the addition of 9 g Se ha(-1) yr(-1) as sodium selenate. Soil Se analysis confirmed the low Se status of the native soil. Mean foliar Se concentration in the control group was 0.05 mg kg(-1). Because plant deficiency may occur at levels less than 0.10 mg Se kg(-1), data provided further evidence for Se deficiency in Belgium plant production. When grown with Se, plant species showed wide variations for Se concentration, ranging from 0.08 to 0.49 mg Se kg(-1). All values were less than 2 mg Se kg(-1), the suggested threshold toxicity level for dairy cattle. There were two different types of plants in terms of response to Se fertilization. Most of the tested plants were known as nonaccumulators. There were also two probable secondary accumulators: Sinapis arvensis and Melilotus albus. Finally, one has to question the reliability of plant Se enhancement using this method when floristic composition is poorly controlled

Effect of groundnut cake substitution by glandless cottonseed kernels on broilers production: animal performance, nutrient digestibility, carcass characteristics and fatty acid composition of muscle and fat

peer reviewedA study has been conducted with broilers to assess, during the rainy season, the effects of groundnut cake substitution by glandless Cottonseed Kernel (CSK), at levels of 0, 25, 50 and 75%. The substitution improved linearly feed intake and animal growth, as well as carcass component weights and allometric parameters. The CSK increased the C18:2 n-6 to C18:1 n-9 ratio, as well in diet as in meat and subcutaneous fat. In order to explain the observed performances, the possibility is considered that broilers used preferentially C18:2 n-6 fatty acids for their metabolism. Complete glandless cottonseed kernels are probably highly valuable for broilers production in warm and wet conditions.Amélioration de la rentabilité de la filière cotonnière au Sénégal

Vitamin E: current knowledges in domestic carnivores. II. Metabolism, requirements and allowances

This paper aims to present the metabolism of vitamin E and the allowances and requirements in men and domestic carnivores. The mechanisms of absorption, distribution, storage and excretion of vitamin E are explained. The metabolism particularities of this vitamin due to the existence of the a-Tocopherol Transfer Protein are developed. The concentrations in lipoproteins and plasma are presented along with their variation factors. Vitamin E units, estimation of requirements and dietary allowances and tolerable upper intake level in men and domestic carnivores are also reviewed. Finally, the use of vitamin E in the petfood industry is discussed.Le but de ce second article est de réaliser une synthèse sur le métabolisme de la vitamine E ainsi que sur ses apports et ses besoins chez l'homme et chez les carnivores domestiques. Les mécanismes d'absorption, de distribution, de stockage et d'excrétion de la vitamine E sont expliqués. Les particularités du métabolisme de cette vitamine liées à l'existence de l'a-Tocopheroi Transfer Protein sont développées. Les concentrations dans les lipoprotéines et dans le plasma sont données, ainsi que leurs facteurs de variation. Les unités de vitamine E, l'estimation des besoins et des apports alimentaires et le niveau d'ingestion maximal tolérable chez l'homme et chez les carnivores domestiques sont également discutés. Enfin, l'utilisation de la vitamine E en fabrication d'aliments pour chien et chat est abordée

Chemistry, nutritional sources and analyses of vitamin E

Vitamin E is a part of the defence mechanism for the inactivation of free radicals and is therefore implicated in the oxidative stress. Chemistry of vitamin E is relatively complex. Vitamin E includes 2 large groups of molecules, tocopherols and tocotrienols, each including 32 stereoisomers. Vitamin E is synthesized in plants, algae, and moulds but not in animals. The greatest quantities of vitamin E are found in cereals and vegetable oils. Vitamin E analyses are difficult to perform. After treatment of a sample with an organic solvent such as ethanol, vitamin E is usually extracted into hexane. Identification and quantification are carried out mainly by chromatography such as normal-phase liquid chromatography and reversed-phase liquid chromatography.La vitamine E intervient dans l'inactivation des formes réactives de l'oxygène et est donc impliquée dans la problématique du stress oxydant. La chimie de la vitamine E est relativement complexe. Le terme vitamine E correspond à 2 grands groupes de molécules: les tocophérols et les tocotriénols, comprenant chacun 32 stéréoisomères. La biosynthèse de la vitamine E s'effectue dans les plantes, les algues et les champignons mais pas chez les animaux. Les quantités les plus importantes sont retrouvées dans les céréales et les huiles végétales. Le dosage de la vitamine E est difficile. Après un traitement de l'échantillon avec un solvant organique tel que l'éthanol, il faut procéder à une extraction, réalisée généralement avec de l'hexane. L'identification et la quantification sont réalisées principalement par chromatographie liquide de haute performance en phase normale ou en phase inverse

Effect of breed, age and sex on selenium content of dromedary

peer reviewedThe dromedary camel is able to produce meat and milk in arid conditions and its production is appreciated by the autochthon population. The aim of this study was to determine the selenium concentration in 61 Longissimus dorsi muscle samples representing three Algerian camel breeds (Tergui, Sahraoui or Naili breeds), the age of the selected camels ranged between 8 months and 13 years old. The muscle samples were collected from the slaughterhouse of Ouargla (South East Algeria) representing 41 males and 20 female. The average content of selenium was 0.216 mg.kg-1of wet tissue, which is higher than values currently reported in most ruminants. The level of Se was not influenced by age and sex. However, Tergui breed contained significantly higher selenium than other breeds, which may be due to diet composition intake. In conclusion, the meat from camels in Algeria is a good source of selenium, assessing its nutritional interest for human

Prediction of organoleptic and technological characteristics of pork meat by near infrared spectroscopy

peer reviewedCette étude met en évidence les potentialités des appareils SPIR pour la prédiction de plusieurs paramètres liés à la qualité de la viande porcine, en particulier les pertes de jus par écoulement. Par ailleurs, cette étude souligne que la validation de la technique, au moyen d’ une série d’ échantillons indépendants, est nécessaire afin de contrôler la capacité réelle des modèles à prédire les différents paramètres. Ces modèles pourraient être améliorés en utilisant un nombre plus élevé d’ échantillons afin d’ augmenter la variabilité dans la base de données et en maîtrisant tous les facteurs pouvant influencer les valeurs spectrales