Stage-specific nutritional management and developmental programming to optimize meat production

Over the past few decades,genetic selection and refined nutritional management have extensively been used to increase the growth rate and lean meat production of livestock.However,the rapid growth rates of modern breeds are often accompanied by a reduction in intramuscular fat deposition and increased occurrences of muscle abnor‑malities,impairing meat quality and processing functionality.Early stages of animal development set the long‑term growth trajectory of offspring.However,due to the seasonal reproductive cycles of ruminant livestock,gestational nutrient deficiencies caused by seasonal variations,frequent droughts,and unfavorable geological locations nega‑tively affect fetal development and their subsequent production efficiency and meat quality.Therefore,enrolling live‑stock in nutritional intervention strategies during gestation is effective for improving the body composition and meat quality of the offspring at harvest.These crucial early developmental stages include embryonic,fetal,and postnatal stages,which have stage‑specific effects on subsequent offspring development,body composition,and meat quality.This review summarizes contemporary research in the embryonic,fetal,and neonatal development,and the impacts of maternal nutrition on the early development and programming effects on the long‑term growth performance of livestock.Understanding the developmental and metabolic characteristics of skeletal muscle,adipose,and fibrotic tissues will facilitate the development of stage‑specific nutritional management strategies to optimize production efficiency and meat quality.

Effects of Tobacco-dedicated Plant Nutrition Regulators on Yield and Quality of Flue-cured Tobacco Leaves

During 2012-2014,field trials were carried out in Huili County,Dechang County and Mianning County of Liangshan Yi Autonomous Prefecture to investigate effects of tobacco-dedicated plant nutrition regulators on yield and quality of fluecured tobacco leaves,aiming at providing reference for tobacco production.According to the results,in tobacco fields applied with tobacco-dedicated plant nutrition regulators,growth period of tobacco was shortened compared with control group;botanical characters（plant height,stem girth,the maximum leaf length,the maximum leaf width,internode length and leaf number） were superior to control group;after application of tobacco-dedicated plant nutrition regulators,yield,output value and the proportion of high-grade and middle-grade leaves were significantly improved compared with control group;moreover,flue-cured tobacco leaves exhibited more coordinated chemical composition.

A Review of Factors Influencing Intramuscular Fat Content in Porcine Meat

Intramuscular fat （IMF）, an important flavor precursor of porcine meat, is closely related to pork quality traits such as pH, color, tenderness, water-holding capacity （WHC） and juiciness, and thus is one of the important factors affecting pork quality. Pork IMF content is not only associated with swine breed on heredity, but also influenced by the alteration of nutrients in diet. These may give a possibility for researchers to improve the IMF content and pork quality by their work on swine breed or heredity, and nutrition regulation in diet. Therefore, this article summarizes the effects of swine breed and nutrition regulation on IMF content briefly to provide some information for future researches.

Studies on HUFA Biosynthesis in a Marine Teleost Siganus Canaliculatus

Marine fish are incapable or have a deft- cient capacity to synthesize highly unsaturated fatty acids （HUFA） from C18 precursors, and thus fish meal and fish oil （FO） are needed in their formulated diets.

Understanding nutritive need in Harmonia axyridis larvae:Insights from nutritional geometry

The multicolored Asian lady beetle,Harmonia axyridis(Pallas)(Coleoptera:Coccinellidae),is an important natural enemy in agricultural ecosystems.In spite of being a carnivore consuming protein-rich preys,the lady beetles often consume carbohydrate-rich food like nectar or honeydew.However,most studies on nutrition regulation of carnivores mainly focus on protein and lipid,two major macronutrients in preys.In this study,nutrition regulation of protein and carbohydrate has been investigated in the 4th instar larvae of H.axyridis using Geometric Framework.We provided the insects two pairs of foods,one a protein-biased one and the second carbohydrate-biased,to determine the intake target.We then confined them to nutritionally imbalanced foods to examine how they regulated food intake to achieve maximal performance.The larvae performed well on the 2 foods that containing the closest P:C ratios to the intake target,but,surprisingly,the lipid content was much lower than that in the choice experiment.The lady beetles seemed to maintain the optimal lipid content by consuming carbohydrate-rich food.Moreover,consuming the carbohydrate-rich food was less metabolically expensive than the protein-rich food.Therefore,switching behavior between plant and animal foods actually reflects their nutritive needs.These findings extended our understanding of predator forage behavior and its influence on food web in ecosystems,and shed light on the role of agri-environment schemes in meeting the nutritional need of predators in field.

Microbiota-gut-brain axis and nutritional strategy under heat stress

Heat stress is a very universal stress event in recent years.Various lines of evidence in the past literatures indicate that gut microbiota composition is susceptible to variable temperature.A varied microbiota is necessary for optimal regulation of host signaling pathways and disrupting microbiota-host homeostasis that induces disease pathology.The microbiota-gut-brain axis involves an interactive mode of communication between the microbes colonizing the gut and brain function.This review summarizes the effects of heat stress on intestinal function and microbiota-gut-brain axis.Heat stress negatively affects intestinal immunity and barrier functions.Microbiota-gut-brain axis is involved in the homeostasis of the gut microbiota,at the same time,heat stress affects the metabolites of microbiota which could alter the function of microbiota-gut-brain axis.We aim to bridge the evidence that the microbiota is adapted to survive and thrive in an extreme environment.Additionally,nutritional strategies for alleviating intestinal heat stress are introduced.