Accurate models and nutritional strategies for specific oxidative stress factors: Does the dose matter in swine production?

Oxidative stress has been associated with a number of physiological problems in swine,including reduced production efficiency.Recently,although there has been increased research into regulatory mechanisms and antioxidant strategies in relation to oxidative stress-induced pig production,it remains so far largely unsuccessful to develop accurate models and nutritional strategies for specific oxidative stress factors.Here,we discuss the dose and dose intensity of the causes of oxidative stress involving physiological,environmental and dietary factors,recent research models and the antioxidant strategies to provide theoretical guidance for future oxidative stress research in swine.

Nutritional strategies for reducing nitrogen, phosphorus and trace mineral excretions of livestock and poultry

Animal agriculture contributes to environmental pollutions through the surplus nitrogen（N）, phosphorus（P）, and trace minerals that animals excrete. Animal nutritionists have sought alternatives to formulate more efficient diets and reduce production costs and environmental concerns. In general, element excretions may be reduced by avoiding the overfeeding of specific elements or using nutritional approaches to improve element utilizations by the animals. Several nutritional strategies are possible for minimizing N, P, and trace mineral excretions： 1） to accurately meet dietary N, P and trace mineral requirements of animals, which includes reducing the dietary crude protein contents with synthetic amino acids or feeding high rumenally undegraded protein, minimizing the adequate levels of dietary P and trace elements, adopting phase or group-feeding program, and considering the bioavailable trace mineral contents in the feed ingredients; 2） to improve the bioavailabilities of dietary N, P, and trace elements for animals by using some additives（enzymes, growth promoters, probiotics, prebiotics, vitamin D isomers, and organic acids）; 3） to use highly available P sources or organic trace elements. In the future, nutrient strategies must be integrated into total production systems so that animal production systems are environmentally safe as well as economically viable.

USING NUTRITIONAL STRATEGIES TO MITIGATE RUMINAL METHANE EMISSIONS FROM RUMINANTS

Within the agricultural sector,animal production contributes to 14.5%of global anthropogenic greenhouse gas emissions and produces around 37%of global CH_(4) emissions,mainly due to ruminal fermentation in ruminants.Over 90%of CH_(4) is synthesized by methanogens in the rumen during carbohydrate fermentation.According to different substrates,methanogenesis pathways can be divided into four categories:(1)hydrogenotrophic pathway;(2)acetoclastic pathway;(3)methyl dismutation pathway;and(4)methylreducing pathway.Based on the principle of biochemical reactions in the methanogenesis pathways,this paper reviews the latest publications on CH_(4) decreases in ruminants and described three nutritional strategies in terms of dietary nutrient manipulation(feeding management,feed composition,forage quality and lipids),microbial manipulation(ionophore,defaunation,methanogen inhibitors and probiotics),and chemical manipulation(nitrate,organic acids,plant secondary metabolites and phlorotannins,or halides in seaweeds).For each mitigation strategy,the review discusses effectiveness for decreasing CH_(4) emissions,application prescription,and feed safety based on results from in vitro and in vivo studies.This review summarizes different nutritional strategies to mitigate CH_(4) emissions and proposed comprehensive approaches for future feeding interventions and applications in the livestock industry.

Which Target Population for Promotion Programs on Health Infant Feeding Practice in Laos?

One of the determinants of the poor improvement in child nutrition indicators observed in Laos is mothers’ feeding practices. These practices are influenced by many socio-environmental factors and are expected to be targets of public health programs against malnutrition. The purpose of this work is to examine how the Lao National Nutrition Strategy (NNS) incorporates the issue of the determinants of the behavior of mothers of young children in its recommendations. We argue that the little consideration brought in the NNS to key determinants of women’s behavior is a major explanatory factor for the poor performance in improving the nutrition status of Lao under-five-year-old children.

Nutritional strategies to alleviate oxidative stress in sows

The performance of high-yielding sows is directly related to the productivity of pig farming. Fetaldevelopment mainly occurs during the last month of pregnancy, and the aggressive metabolic burden ofsows during this stage eventually leads to systemic oxidative stress. When affected by oxidative stress,sows exhibit adverse symptoms such as reduced feed intake, hindered fetal development, and evenabortion. In addition, milk synthesis during the lactation period causes a severe metabolic burden. Thebiological response to oxidative stress during this period is associated with a decrease in milk production,which further affects the growth of piglets. Understanding the nutritional strategies to alleviateoxidative stress in sows is crucial to maintain their reproduction and lactation performance. Recently,advances have been made in the field of nutrition to relieve oxidative stress in sows during late pregnancyand lactation. This review highlights the nutritional strategies to relieve oxidative stress in sowsreported within the last 20 years.

Research progress on anti-stress nutrition strategies in swine

In swine production,stress is a common encounter that leads to serious bacterial infection and adverse effects on growth performance.Though antibiotics have been frequently used to control pathogen spread,sustained negative impacts from antibiotics have been found to affect intestinal integrity and the immune system.Multiple nutritional strategies have shown potential to counteract stress and replace antibiotics,including functional amino acids,low protein diet,plant extracts,organic acids,prebiotics,probiotics,minerals and vitamins.These additives relieve the stress response in swine via different mechanisms and signal transduction pathways.Based on the overview of signaling pathways and stress models,this review highlights the potential of nutritional strategies in swine for preventing or treating stress-related health problems.For wider application in the pig industry,the dose ranges measured require for further validation in different physiological contexts and formulations.In the future,micro-fluid devices and novel stress models are expected to enhance the efficiency of screening for new anti-stress candidates.