L’élevage est souvent perçu comme inefficient pour produire des denrées alimentaires pour l’Homme car les animaux consomment davantage de végétaux qu’ils ne produisent de viande, de lait ou d’œufs. Le calcul de l’efficience nette de conversion des aliments en ne considérant dans le calcul que la part potentiellement consommable par l’Homme des aliments utilisés par les animaux permet de relativiser ce constat. En effet, une large part des aliments consommés par les animaux d’élevage (fourrages, coproduits…) n’est pas directement consommable par l’Homme. Appliqués à des systèmes d’élevage français, les calculs d’efficience nette montrent que toutes les productions animales (bovins laitiers et à viande, ovins à viande, porcins, poulets de chair, poules pondeuse) peuvent être producteurs nets de protéines à condition de maximiser la part des végétaux non valorisables en alimentation humaine dans les rations. Le calcul de l’efficience nette est très sensible à l’estimation de la part des aliments utilisés en alimentation animale qui peut être directement valorisée par l’Homme. Celle-ci varie fortement d’une matière première à l’autre selon les habitudes alimentaires et les technologies agroalimentaire qui peuvent évoluer dans le temps. Il est donc nécessaire d’analyser les résultats d’efficience nette à travers plusieurs scénarios de valorisation des matières premières végétales. De même le niveau de valorisation du cinquième quartier de la carcasse des animaux d’élevage pour l’alimentation humaine est très variable et influence sensiblement les résultats d’efficience nette. Enfin, la prise en compte du différentiel de qualité entre les protéines végétales permettrait d’affiner les calculs d’efficience protéique.
Environmental and economic performances of livestock production are related largely to the production of complete feeds provided on commercial farms. Formulating feeds based on environmental and economic criteria appears a suitable approach to address the current challenges of animal production. We developed a multiobjective (MO) method of formulating feed which considers both the cost and environmental impacts (estimated via life cycle assessment) of the feed mix. In the first step, least-cost formulation provides a baseline for feed cost and potential impacts per kg of feed. In the second, the minimised MO function includes normalised values of feed cost and impacts climate change, P demand, non-renewable energy demand and land occupation. An additional factor weights the relative influence of economic and environmental objectives. The potential of the method was evaluated using two scenarios of feed formulation for pig, broiler and young bulls. Compared to baseline feeds, MO-formulated feeds had lower environmental impacts in both scenarios studied (−2 to −48 %), except for land occupation of broiler feeds, and a moderately higher cost (1–7 %). The ultimate potential for this method to mitigate environmental impacts is probably lower than this, as animal supply chains may compete for the same low-impact feed ingredients. The method developed complements other strategies, and optimising the entire animal production system should be explored in the future to substantially decrease the associated impacts.
-Minerals, including trace-elements, and vitamins are currently introduced into the pig diet in order to obtain suitable performances for the modern pig genotype bred in confinement. Most of the mineral and vitamin contents of cereals and usual protein compounds are characterized by their poor and variable availability. Supplemental diets are then usually needed. This paper, based on literature data, reviews the pig requirement for minerals and vitamins in order to ensure economic and profitable performance. Recent research has focused on phosphorus due to environmental considerations. The widespread use of microbial phytase has decreased the need for inorganic phosphates. Cereals are particularly deficient in calcium and sodium, consequently limestone and salt are necessary to meet the pig need for these minerals. Zinc and copper are recognized as growth promoting agents but their use at high levels is detrimental to the environment. The pig diets usually contain supplemental contents of iron, manganese, cobalt, iodine and selenium. The need for these elements in pig diets is described individually. Vitamin E and choline represent the most expensive vitamins added. Choline is then usually not incorporated into the pig fattening diet taking into account the choline contents of the raw materials, while vitamin E is included at a lower level than those which improve the meat quality. Our recent research has dealt with increased levels of vitamins added in combination, calculating higher requirement of the modern pig genotype. Fewer improvements have been obtained in this way, suggesting that recommendations proposed by INRA in 1984 are mainly justified.Key Words: environment, enzymes, feeding, meat quality, modern genotype, nutritional requirements Que níveis de vitamina e mineral são recomendados em rações de suínos?RESUMO -Minerais, inclusive elementos traços, e vitaminas são atualmente adicionados nas rações de suínos objetivando obter performance adequada para genótipos modernos criados em confinamento. A maioria do conteúdo de mineral e vitamina dos cereais e compostos protéicos é caracterizada por sua baixa e variável disponibilidade. Dietas suplementares são então geralmente necessárias. Este artigo, baseado em dados de literatura, revê a exigência do suíno para minerais e vitaminas objetivando assegurar desempenho econômico e rentável. Recente pesquisa tem focado no fósforo devido às considerações ambientais. A propagação do uso de fitase microbial reduziu a necessidade de fosfato inorgânico. Cereais são particularmente deficientes em cálcio e sódio, consequentemente calcário e sal são necessários para atender a necessidade do suíno para estes minerais. Zinco e cobre são reconhecidos como agentes promotores de crescimento, mas sua utilização em elevados níveis são prejudiciais ao meio-ambiente. As rações de suínos geralmente contêm quantidades suplementares de ferro, manganês, cobalto, iodo e selênio. A necessidade para estes elementos nas rações de suínos é descrita individualmente. A vitamina E ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.