Concept and Research Progress of Functional Feed

The concept and research progress of functional feed were summarized. Compared with the basic nutrition, functional feed is a kind of new health care feed which contains functional ingredients, and can promote the growth of animal health, enhance immunity, improve the quality of animal products, improve the level of ani- mal welfare, reduce environmental pollution, improve the ecological environment, as well as increase the economic benefits. Studies on the functional feed are mainly concentrated in the development of functional feed products, and but few to under- stand the compositions and compatibility mechanism of the functional components that have the function effects. Moreover, these functional components are low in plants, so the wide application in feed industry requires research on biological engi- neering and chemical synthesis, which will become the trend of future research.

Winery by‑products as a feed source with functional properties:dose–response effect of grape pomace,grape seed meal,and grape seed extract on rumen microbial community and their fermentation activity in RUSITEC

Background Grape and winery by-products have nutritional values for cattle and also contain functional compounds like phenols,which not only bind to protein but can also directly affect microbiota and their function in the rumen.We characterized the nutritional and functional effects of grape seed meal and grape pomace as well as an effective dosage of grape phenols on ruminal microbiota and fermentation characteristics using a rumen simulation technique.Results Six diets(each n=8)were compared including a control diet(CON,no by-product),a positive control diet(EXT,CON+3.7%grape seed extract on a dry matter(DM)basis),two diets with grape seed meal at 5%(GS-low)and 10%(GS-high),and two diets with grape pomace:at 10%(GP-low)and 20%(GP-high),on a DM basis.The inclusion of the by-product supplied total phenols at 3.4%,0.7%,1.4%,1.3%,and 2.7%of diet DM for EXT,GS-low,GS-high,GP-low,and GP-high,respectively.Diets were tested in four experimental runs.All treatments decreased ammonia concentrations and the disappearances of DM and OM(P<0.05)compared to CON.EXT and GP-high lowered butyrate and odd-and branch-chain short-chain fatty acids while increased acetate compared to CON(P<0.05).Treatments did not affect methane formation.EXT decreased the abundance of many bacterial genera including those belonging to the core microbiota.GP-high and EXT consistently decreased Olsenella and Anaerotipes while increased Ruminobacter abundances.Conclusion The data suggest that the inclusion of winery by-products or grape seed extract could be an option for reducing excessive ammonia production.Exposure to grape phenols at a high dosage in an extract form can alter the rumen microbial community.This,however,does not necessarily alter the effect of grape phenols on the microbial community function compared to feeding high levels of winery by-products.This suggests the dominant role of dosage over the form or source of the grape phenols in affecting ruminal microbial activity.In conclusion,supplementing grape phenols at about 3%of diet DM is an effective dosage tolerable to ruminal microbiota.

Effects of α-glucosidase Inhibitors on the Function of Mulberry Leaf Extract as an Additive in Feedstuff

The mulberry juice contains high concentrations of α-glucosidase inhibitors that affect glycometabolism and cause diarrhea in animals, thereby affecting the de-velopment and application of mulberry （Morus alba L.） as feedstuff resources. ln this study, the effects of mulberry leaf extract with and without removal of mulberry juice on starch metabolism were analyzed and compared. The results showed that mul-berry leaf extract with removal of mulberry juice exhibited significantly lower inhibi-tion rate on starch metabolism compared with mulberry leaf extract without removal of mulberry juice. ln animal feeding trials, piglet feedstuff was added with 10% mul-berry leaf powder; compared with mulberry leaf powder without removal of mulberry juice, experimental piglets fed with mulberry leaf powder with removal of mulberry juice exhibited significantly improved weight gain and significantyl reduced diarrhea rate.

Microalgal-based feed:promising alternative feedstocks for livestock and poultry production

There is an immediate need to identify alternative sources of high-nutrient feedstocks for domestic livestock productionand poultry,not only to support growing food demands but also to produce microalgae-source functional foods withmultiple health benefits.Various species of microalgae and cyanobacteria are used to supplement existing feedstocks.Inthis review,microalgae have been defined as a potential feedstock for domestic animals due to their abundance ofproteins,carbohydrates,lipids,minerals,vitamins,and other high-value products.Additionally,the positive physiologicaleffects on products of animals fed with microalgal biomass have been compiled and recommendations are listed toenhance the assimilation of biomolecules in ruminant and nonruminant animals,which possess differing digestivesystems.Furthermore,the role of microalgae as prebiotics is also discussed.With regards to large scale cultivation ofmicroalgae for use as feed,many economic trade-offs must be considered such as the selection of strains with desirednutritional properties,cultivation systems,and steps for downstream processing.These factors are highlighted withfurther investigations needed to reduce the overall costs of cultivation.Finally,this review outlines the pros and cons ofutilizing microalgae as a supplementary feedstock for poultry and cattle,existing cultivation strategies,and theeconomics of large-scale microalgal production.

Ecology of macrozoobenthic communities in two plateau lakes of Southwest China

Ecological studies on macrozoobenthos were conducted in two small plateau lakes in the Yunnan-Guizhou Plateau, Southwest China： Xingyun Lake （XL）, a eutrophic lake whose main source of primary production was phytoplankton （Chl α=99.76±24.01 μg/L）, and Yangzong Lake （YL）, a mesotrophic lake. Sampling was carried out from October 2002 to May 2004. Altogether 23 benthic taxa were identified in XL and 21 taxa in YL. The density of benthos in XL was much lower than that in YL, but the biomass was about equal in the two lakes, being I 423 ind/m^2 and 8.71 g/m^2 in XL and 4 249 ind/m^2 and 8.60 g/m^2 in YL. The dominant species were Limnodrilus hoffmeisteri, Branchiura sowerbyi, Aulodrilus pluriseta and Chironomus sp. in XL and Limnodrilus hoffrneisteri, Aulodrilus pluriseta and Bellamya sp. in YL. Seasonal fluctuation occurred, showing richer species in summer and winter, but the density and biomass varied in different ways in the two lakes. Analyses on functional feeding groups indicate that collector-gatherers were predominant, but the relative abundances of other groups were different. Stepwise multiple regression analysis demonstrated that the water depth, conductivity and chlorophyll a were the key factors affecting macrozoobenthic abundance in the lakes.

Temporal and spatial variation of fish assemblages in Dianshan Lake, Shanghai, China

Using multi-mesh gillnets and trawls, the fish communities in Dianshan Lake at 6 stations from Oct. 2009 to Jul. 2010 were investigated seasonally to reveal the biodiversity and its spatial and temporal distribution patterns. The long-term changes in their structural characteristics were then analyzed to identify the main infl uencing factors and several measures for lake restoration were put forward. Thirty six species, belonging to 9 family and 30 genera, were collected, amongst which, the order Cypriniformes accounted for 61.1% of the total species number. In terms of importance value, Cypriniformes was the predominant group, Coilia nasus the dominant species, while Cyprinus carpio and Rhinogobius giurinus were the subdominant taxa. The community types did not differ among stations, but between seasons. There were no significant differences between seasons and among stations in species diversity, but richness differed both spatially and seasonally. Along with the process of eutrophication and the drastic reduction of the area colonized by macrophytes from 1959 to 2009–2010, the fish diversity declined markedly, and species numbers of herbivores and piscivores declined proportionately more than those of invertivores, omnivores, and planktivores. The decline of potamophilus and river-lake migratory fish was more marked than those of sedentary, river-sea migratory, and estuarine fishes. Eutrophication concomitant with sharp reduction of macrophyte area and overfishing may be the main reasons for the decline in fish diversity in Dianshan Lake.

An exploratory analysis of benthic macroinvertebrates as indicators of the ecological status of the Upper Yellow and Yangtze Rivers

This study presents findings of the first systematic analysis of aquatic biotic assemblages in the source region of the Yellow and Yangtze Rivers. It provides an initial basis with which to select representative organisms as indicators to assess the aquatic ecological status of rivers in this region. Macroinvertebrates are considered to be good indicators of long-term environmental changes due to their restricted range and persistence over time. Field investigations of macroinvertebrates were conducted in August 2009 in the source region of the Yellow River, and in July 2010 in the source region of the Yangtze River. Altogether 68 taxa of macroinvertebrates belonging to 29 families and 59 genera were identified. Among them were 8 annelids, 5 mollusks, 54 arthropods and 1 other animal. In the source region of the Yellow River, taxa number, density and biomass of macroinvertebrates were 50, 329 individuals m2 and 0.3966 g dry weight m2, respectively. Equivalent figures for the source region of the Yangtze River were 29, 59 individuals m2 and 0.0307 g dry weight m-2. The lower benthic animal resources in the source region of the Yangtze River are ascribed to higher altitude, higher sediment concentration and wetland degradation. Preliminary findings of this exploratory study indicate that hydroelectric power stations had a weak impact on benthic dwellers but wetland degradation caused by a series of human activities had a catastrophic impact on survival of macroinvertebrates. Ecological protection measures such as conservative grazing and vegetation management are required to minimize grassland degradation and desertification, and reduce soil erosion rate and river sediment discharge.