Technical-Economic Performance, Carcass and Meat Quality of COBB500 Broilers Fed Rations Incorporating Mango By-Product Feeds in Ivory Coast (West Africa)

The study evaluated the growth performance and carcass quality of COBB500 broilers fed two experimental rations incorporating feed and mango fine ED10 for a batch of 83 birds, ED20 (batch of 83 birds) in comparison with a commercial control ration CCD (84 birds). For this purpose, 250 day-old chicks of this breed were purchased in Korhogo and transported to Tengréla in Ivory Coast for rearing. The results show that substituting mango provender ans and mango seed flour for maize resulted in rations with costs per kgMS of 215.35FCFA, 2016.93FCFA and 320FCFA for the ED10, ED20 and CCD rations respectively. The production costs per kg of chicken (FCPkgLW) of the CCD ration were significantly higher than those of the ED10 and ED20 (p 0.05). ADGs were significantly different and decreasing from CCD, ED20 to ED10 (p 0.05). Average weights at 42nd day for ED20 and CCD were homogeneous (p > 0.05) and significantly higher than for ED10 (p 0.05). By day 49th the average weight of ED20 had reached and exceeded that of CCD by day 42nd. PSLW, HCW and CCW were significantly different and decreasing from CCW, ED20 to ED10 (p 0.05). Average hot (HCY) and cooled (CCY) carcass yields of ED20 and CCD rations were comparable (p > 0.05) and significantly higher than those of ED10 ration (p = 0.009) and 0.003). Average drumstick and neck weights were significantly higher and lower for CCD, ED20 and ED10 (p 0.05). For all other parts of the cut, the average weights of the CCD ration were significantly higher (p 0.05) than those of the ED20 and ED10 rations, which were homogeneous (p 0.05). The incorporation of mango provender and mango seed flour in broiler rations offers the prospect of reduced production costs, less competition between man and animals over cereals, and lean meat production that is more appreciated than that of chickens fed conventional feed. As it stands, the ED20 ration can be recommended as a growth diet for broilers. It would be necessary to determine the levels of anti-nutritional substances in mango feeds and to assess the in vivo digestibility of mango ingredients and the diets incorporating them.

Biological properties of essential oil emphasized on the feasibility as antibiotic substitute in feedstuff

The discovery and application of antibiotics in animal feeds have boomed the development of intensive animal husbandry in the last century,until the emergence of antibiotics-resistant bacteria.To alleviate the risks aroused by antibiotics-resistant bacteria,effective antibiotic substitutes are urgently needed to replace antibiotics.Essential oils(EOs)derived from plants are illustrated as the promising antibiotic substitutes used in animal feeds,as same as their current views for poultry and livestock industries in the future.It has been widely demonstrated that the phytochemicals in EOs show multiple biofunctionability and are less likely to induce resistance in bacteria.The beneficial effects of EOs feed supplementation on the intestinal inflammation,intestinal flora,immunity,digestion,and growth performances have been already extensively examined.However,the cost-effectiveness,odor,volatility,instability and bioavailability are the challenges in effectively utilizing EOs in animal intestines.Based on previous researches,and these challenges can partially be resolved by microencapsulation and nanotechnology are promising techniques to deal with these challenges.This article presents the feasibility and foundation of EOs application as antibiotic substitutes in animal feeds,and illustrates the mechanisms,functional performances and superiority of EOs compared with antibiotics.

Influence of Sorbent Type on Drying Efficiency, Production Costs and Nutritional Values of Mango By-Products Feeds for Livestock

The aim of the study was to determine the best food absorbents between wheat, rice and maize bran and palm kernel cake, from a technical and economic point of view, in order to make a better recommandation for their use in the production process of food based on mango by-products (peels, peels + pulp). To this end, series of 18 kg of fresh feed were prepared and spread out in a stall for sun-drying using a randomized Fisher system. Preparations were made using either mango peels (75%) + absorbent (25%) or pulp + mango peels (67%) + sorbent (33%). The results show that mango Peel feed loses more water (WL) with lover production yields (PY), higher mango incorporation rates into dry feed (MRI), longer drying times (UDT) and lower production costs (CPkgPD) than mango peel + pulp. The average DM, MAT, ADF and NDF fiber contents were almost equal to those of mango peels + pulp feed. The average Crude Fiber (CF) (25.13%) and DEp (2839 kcal/kgDM) contents were higher for mango skin feed than for mango skin + pulp feed, at 8.59% and 2536 for MAT and DEp respectively. Mango peels + wheat bran (PSB25) and whole mango (MESB33) feeds recorded the highest and almost equal levels of TCP, NDF and MM. Production costs per kg of feed dry mater (CPkgDM) for feed produced at 25% were on average 33% higher than for whole mango (WM) feed. Excluding mango raw material, palm kernel meal (PK), rice bran (RB), maize bran (MB) and wheat bran (WB) can be ranked 1st, 2nd, 3rd and 4th in terms of cumulative performance of production parameters. Producers can then choose the type of sorbent they wish to use according to this ranking and the local availability of the sorbent. These feeds can be used for both ruminants and monogastrics, but are better suited to ruminant feeding due to their high fiber content.

Utilisation of Non-Conventional Animal Waste as Feeds by Multiple Livestock Species Farmers in Lake Victoria Crescent of Central Uganda

A cross-sectional survey was conducted to establish the utilisation of non-conventional animal waste in multiple livestock species systems. Farmers (150) were selected from four out of ten districts of Central Uganda in Lake Victoria Crescent. A structured questionnaire was used and descriptive analysis showed that over 80% are smallholder farmers on 3.0) years. Household husbands (80%) significantly (P 1.0) as they cause poor livestock health due to pathogens, parasites and toxins which are associated (OD > 1.0) with poor growth, mortality and condemnation of livestock products. The remedy to unsafe non-conventional feeds is to apply effective solar-heating (75%), chemical and ensiling treatment methods. The study showed that there are no significant (P < 0.001) public health risks associated with utilising treated non-conventional feeds instead it improves production and sustainability of multiple livestock species systems.

The Applied Research of Soybean Peptide in Feedstuffs

The soybean peptide has the trait of amino acid balance,digestible and easy to absorb,low allergy and low antigenicity.Furthermore,it also showed the feature of good mobility and thermal stability at high concentrations.This paper seeks to study the processing and nutritional characteristics of soybean peptide.And on that basis to lucubrate soybean peptide as a safe,efficient feedstuffs additives.The aim is to improve the feedstuffs quality.

基于Feeds的社交网络活跃度分析

从用户产生和消费Feeds的角度分析社交网络变得不活跃的原因,通过分析人人网某大学社区用户长周期的Feeds行为来探讨该社区用户活跃度的变化。通过对用户活跃性周期和Feeds时间间隔的分析,发现越来越多的用户产生Feeds的活跃度在下降,并导致其他用户接收到的信息流的流速和多样性下降。社交网络用户由于各种原因离开或变得不活跃,并通过信息流对其朋友圈形成负向反馈,这可能是社交网络变得不活跃的深层原因。模拟实验表明,30%的初始不活跃用户会使得整个社区的信息流快速下降,并导致整个社区不活跃。

Occurrence of Aflatoxin B_(1),deoxynivalenol and zearalenone in feeds in China during 2018-2020

Background:The current study was conducted to investigate the individual and combined occurrence of aflatoxin B_(1)(AFB_(1)),deoxynivalenol(DON)and zearalenone(ZEN)in feeds from various Provinces of China during 2018 to 2020.A total of 3,507 feed samples,including 2,090 feed ingredients and 1,417 complete feed samples,were collected from different areas of China for mycotoxins analysis.Results:The individual contamination of AFB_(1),DON and ZEN were present in more than 81.9%,96.4% and 96.9% of feed samples,respectively,with average concentration ranges of AFB_(1) between 1.2-27.4μg/kg,DON between 458.0-1,925.4μg/kg and ZEN between 48.1-326.8μg/kg.Notably,0.9%,0.5% and 0.1% of feed ingredients,and 1.2-12.8%,0.9-2.9% and 0-8.9% of complete feeds for pigs,poultry and ruminants with AFB_(1),ZEN and DON that exceeded China’s safety standards,respectively.Moreover,more than 81.5%of feed ingredients and 95.7% of complete feeds were co-contaminated with various combinations of these mycotoxins.Conclusion:This study indicates that the feeds in China were universally contaminated with AFB_(1),DON and ZEN during the past 3 years.These findings highlight the significance of monitoring mycotoxin contaminant levels in the domestic animal feed,and the importance of carrying out feed administration and remediation strategies for mycotoxin control.

The effect of enzymes on release of trace elements in feedstuffs based on in vitro digestion model for monogastric livestock

Background: This experiment was conducted to study the effect of different feed enzymes(phytase,xylanase,β-glucanase) on release rate of trace elements(Fe,Cu,Mn and Zn) in 6 commonly used feedstuffs(corn,wheat,barley,soybean meal,wheat bran,wheat middlings) by using an in vitro model,simulating the digestive processes in stomach for 2 h and then in small intestine for 6 h at 39 °C.Results: Phytase raised(P < 0.05) the release rate of Cu and Zn in corn,Cu,Zn and Mn in wheat,Cu in barley,Cu,Zn and Mn in soybean meal,Zn,Fe in wheat bran and Zn,Fe,Mn in wheat middlings.The release rate of various trace elements in feedstuffs was increased after xylanase addition.Compared with the control group,the release rate of soluble Cu in corn,wheat,barley and soybean meal,soluble Zn in corn,wheat and wheat middlings and soluble of Mn in corn,wheat,barley and wheat bran increased(P < 0.05) after xylanase treatment.After the treatment of β-glucanase,the release rate of soluble Cu in corn,wheat and wheat bran,soluble Fe in barley,soybean meal and wheat bran and soluble Mn in corn and wheat bran all increased(P < 0.05) compared with the control group.In each feedstuff,after corresponding enzyme treatment,the contents of phytic acid,xylan and β-glucan were significantly lower than those of the control group(P < 0.05).Conclusions: Results showed that bound trace elements in feedstuffs can be released by feed enzymes.It may be necessary to take the trace elements in feedstuffs into account in the actual feed preparation including feed enzymes.

Occurrence of mycotoxins in feed ingredients and complete feeds obtained from the Beijing region of China

Background：The current study was carried out to provide a reference for the control of mycotoxin contamination in feed ingredients and complete feeds for swine.Methods：A total of 55 feed ingredients,including 14 corn,13 wheat bran,11 soybean meal and 17 dried distillers grains with solubles（DDGS） as well as 76 complete swine feeds including 7 creep feeds,14 starter feeds,14 grower feeds,18 grower-finisher feeds,10 gestating sow feeds,and 13 lactating sow feeds were randomly collected from15 swine farms located in the Beijing region of China from July to August 2011.Immunoaffinity clean-up,using High-Performance Liquid Chromatography（HPLC） in combination with UV or Fluorescence Detection,was used for quantitative analysis of aflatoxin B,（AFB,）,deoxynivalenol（DON）,zearalenone（ZEA） and ochratoxin A（OTA） in the ingredients and complete feeds.Results：DON and ZEA were the most prevalent mycotoxins found.DON was detected at percentages of 93,92,54,100 and 97%with a mean level of 1.01,0.44,0.05,1.36 and 0.65 ppm in the samples of corn,wheat bran,soybean meal,DDGS and complete feeds,respectively.The detected percentages of ZEA were 100,100,54,100 and 100 with mean levels of 109.1,14.9,9.2,882.7 and 58.9 ppb in the same samples.In the wheat bran and soybean meal samples,the content of all four mycotoxins were below the maximum limits set by Chinese regulations while the percentage of samples that exceeded regulatory limits were 7,57 and 7%for corn,and 7,14 and 3%for the complete feeds for AFB,,DON and OTA respectively.DDGS showed the most serious mycotoxin contamination and the percentage of samples that exceeded regulatory limits were 6,88 and 41%,for AFB,,DON and ZEA,respectively.Conclusions：This paper is the first to present data on the natural occurrence of AFB,,DON,ZEA and OTA in ingredients and complete feeds obtained from swine farms in China＇s Beijing region.The data shows that feed ingredients and complete swine feeds obtained from these farms are most often contaminated with DON followed by contamination with AFB,and ZEA.

Are children on jejunal feeds at risk of iron deficiency?

Children on exclusive jejunal feeding may be at risk of iron deficiency due to the feeds bypassing the duodenum,which is the primary site for iron absorption.We describe the biochemical and hematological features of six children on exclusive jejunal feeding who did not receive iron supplementation.At a mean(standard deviation)period of 11(6.5)mo after commencing jejunal feeds,there was a significant reduction in both serum iron(18.5 g/L vs 9.8 g/L,P=0.01)and transferrin saturation levels(23.1%vs 13.7%,P=0.02),suggesting iron deficiency.However,there was no significant change in ferritin,hemoglobin and mean corpuscular volume levels post-commencement of jejunal feeds.This may be the result of small bowel adaptation in response to early iron deficiency.Larger and longer term prospective studies are required to investigate if children on jejunal feeds are at risk of developing iron deficiency.

Fabrication and analysis of nano-structured thermal spraying feeds

A kind of thermal spray nanostructured Al2O3 and TiO2 feeds fabricating technology was investigated.Agglomerated nanogranules prepared by spray drying were heat treated in order to be dense, and there were two sintering technologies used, i.e. high temperature electric furnace sintering and high velocity flame sintering, respectively. The results indicate feeds phase components using high temperature electric furnace sintering at 1 200 ℃,1 300 ℃ and 1 400 ℃ do not change, and grain sizes of nano-Al2O3 and TiO2 grow little at 1 200 ℃ and 1 300 ℃,while grain sizes of nano-Al2O3 and TiO2 grow obviously, and the grain size of nano-TiO2 is larger than 100 nm at 1400 ℃. Phase components of the feeds using high velocity flame sintering change, where α-Al2O3 changes to γ-Al2O3 and rutile TiO2 changes to brookite TiO2, though grain size of nano-Al2O3 does not grow and is less than 100 nm because cooling velocity is too quick. Compared with these two heat treatment technology, the technology using electric furnace to treat nanostructured Al2O3 and TiO2 feeds is more suitable.

OPTIMAL MODEL OF COMBINED PHASE CENTER FOR HORN FEEDS AND ITS COMPUTATIONAL METHOD

A definition of combined phase center for horn feeds is given.Formulas of E-planeand H-plane combined phase center for conical horns and the corresponding Optimal model arepresented,and a fast optimization method for solving this model is described.By using thismethod,the phase center of corrugated horn is discussed and calculated,and the variation of thephase center with distance and operating frequency is given.

Aflatoxin Contamination and Rancidity in Locally Processed Commercial Fish Feeds and Ingredients along the Value Chain in Wakiso and Kampala Districts, Uganda

Aflatoxin contamination and rancidity in locally processed commercial fish feeds and ingredients along value chains is a Public and Animal health hazard. The study established the level of aflatoxin contamination, peroxide value (PV), Anisidine value (AnV), and their associated factors at storage areas among farmers, processors, traders, factories, and landing sites in the Wakiso and Kampala districts. The value chain actors were purposively selected in a cross-sectional study based on access to the feed store and the use of locally processed commercial fish feeds on farms. Data collected were statistically analyzed in SPSS version 20. All the samples (45) were positive for aflatoxin contamination and PV with 51% (23/45) of samples being contaminated with “above acceptable” aflatoxin levels and 66.6% (30/45) of samples with “above acceptable” PV. The overall percentage of “above acceptable” AnV was 11/29 (37.9%). Samples from factories were within acceptable contamination levels. Multivariate logistic regression analysis revealed no significant difference between aflatoxin contamination, peroxide, and Anisidine value with storage factors for locally processed commercial fish feeds and ingredients. The study recommended the purchase of fish feeds from factories and a larger study on storage factors responsible for aflatoxin contamination and rancidity in fish feeds in Uganda.

Bioaccumulative Characteristics of Polybrominated Diphenyl Ethers in Channel Catfish and Fish Feeds from China

PBDEs are widely used brominated flame retardant, which are increasingly reported in the environment. Concentrations of thirteen PBDEs in a large number of channel catfish and fish feeds collected from Hubei province of China were investigated in this study. A fast isotopic dilution GC-MS method was firstly developed to simultaneously determine thirteen PBDEs in channel catfish and fish feeds in this study, and especially for the first time PBDEs in fish feeds. Pressurized liquid extraction and multi-layer silica gel column chromatography cleanup were used, some important steps and crucial parameters were modified and intensified compared with other literatures, and GC and MS conditions were optimized. The limits of quantitation values of 0.25 - 5 μg·kg-1 wet weight in channel catfish were calculated for PBDEs;so did 1 - 20 μg·kg-1 wet weight in fish feeds. In addition, good repeatability and accuracy of the whole method were achieved. The established methods were therefore suitable for the simultaneous determinations of thirteen PBDEs in these samples at trace contamination levels. Using the established methods, PBDEs emerged in 10 of 180 channel catfish and 13 of 115 fish feeds, and the dominant PBDEs homologues were PBDE-28, PBDE-47, PBDE-100, PBDE-99, PBDE-154, PBDE-153 and PBDE-183. The detection rates of seven PBDEs congeners were in turn respectively 1.74%, 7.83%, 4.35%, 5.22%, 3.48%, 2.61% and 2.61% in fish feeds, and detection rates of seven PBDEs congeners were in turn respectively 1.11%, 3.89%, 2.22%, 1.67%, 1.11%, 1.11% and 1.11% in channel catfish. There was significant correlation in PBDEs between matching channel catfish and fish feeds (R2 = 0.742, P < 0.001, n = 30), suggesting that fish feeds contaminated with PBDEs possibly resulted in PBDEs residual in channel catfish through biological transfer.

Sensing Semantics of RSS Feeds by Fuzzy Matchmaking

RSS feeds provide a fast and effective way to publish up-to-date information or renew outdated contents for information subscribers. So far RSS information is mostly managed by content publishers but Internet users have less initiative to choose what they really need. More attention needs to be paid on techniques for user-initiative information discovery from RSS feeds. In this paper, a quantitative semantic matchmaking method for the RSS based applications is proposed. Semantic information is extracted from an RSS feed as numerical vectors and semantic matching can then be conducted quantitatively. Ontology is applied to provide a common-agreed matching basis for the quantitative matchmaking. In order to avoid semantic ambiguity of literal statements from distributed and heterogeneous RSS publishers, fuzzy inference is used to transform an individual-dependent vector into an individual-independent vector. Semantic similarities can be revealed as the result.

Heavy metals pollution in poultry and livestock feeds and manures under intensive farming in Jiangsu Province, China

The heavy metals pollution in poultry and livestock feeds and manures under intensive farming in Jiangsu Province was investigated. 97 feed and manure samples were sampled from 31 farming plants in 10 major cities of Jiangsu. 14 metals, including Zn, Cu, Pb, Cd, Cr, Ni, Mo, Mn, Ba, Co, Sr, Ti, As and Hg, were analyzed after samples acid digestion. The results showed that the most feed samples contained high concentration of metals exceeding National Hygienical Standard for Feeds. Meanwhile, it was found that Cu, Zn, Pb, Cd and Cr concentrations in animal manures were also high, for example, Cu concentration in a manure sample reached to as much as 1726 3 mg/kg. Heavy metals loading quantities in soil per year were then calculated when metals contaminated organic fertilizers were applied, and its effects on soil environmental quality were further evaluated.

Dual potential of microalgae as a sustainable biofuel feedstock and animal feed

The rise in global population has led to explorations of alternative sources of energy and food. Because corn and soybean are staple food crops for humans, their common use as the main source of dietary energy and protein for food-producing animals directly competes with their allocation for human consumption. Alternatively, de-fatted marine microalgal biomass generated from the potential biofuel production may be a viable replacement of corn and soybean meal due to their high levels of protein, relatively well-balanced amino acid profiles, and rich contents of minerals and vitamins, along with unique bioactive compounds. Although the full-fatted （intact） microalgae represent the main source of omega-3 （n-3） polyunsaturated fatty acids including docohexaenoic acid （DHA） and eicosapentaenoic acid （EPA）, the de-fatted microalgal biomass may still contain good amounts of these components for enriching DHA/EPA in eggs, meats, and milk. This review is written to highlight the necessity and potential of using the de-fatted microalgal biomass as a new generation of animal feed in helping address the globa energy, food, and environmental issues. Nutritional feasibility and limitation of the biomass as the new feed ingredient for simple-stomached species are elaborated. Potential applications of the biomass for generating value-added animal products are also explored.

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.

Distribution of Heavy Metals in Common Energy Feedstuffs and Protein Feedstuffs in Sichuan Province

[ Objectives] The paper was designed to investigate the heavy metal distribution in energy feedstuffs and protein feedstuffs commonly used in Sichuan Province, in order to provide scientific basis for safe production of feedstuffs and animal products. [ Methods] The contents of manganese （ Mn）, copper （ Cu）, zinc （Zn）, vanadium （V）, chromium （Cr）, cobalt （Co）, nickel （Ni）, selenium （Se）, molybdenum （Mo）, cadmium （Cd）, arsenic （As）, mercury （Hg） and lead （Pb） in 68 samples of energy feedstuffs [ corn, wheat, distillers dried grains with solubles （DDGS）, corn bran with syrup, wheat bran and rice bran ] and 61 samples of protein feedstuffs （corn gluten meal, corn germ meal, soybean meal, rapeseed meal and cottonseed meal） collected from Sichuan province were determined by inductively coupled plasma mass spectrometry （ICP-MS）. [ Results] （ 1 ） The over standard rates of Cu, Cr and Pb in corn were 5.00%, 20.00% and 5.00%, respectively; and thc means of over standard samples were 11.00, 1.41 and 1.06 mg/kg, respectively. The over standard rates of Cu, Zn, Cr, Sc and Pb in wheat were 50.00%, 30.00%, 50.00%, 20.00% and 30.00%, respectively ; and the means of over standard samples were 12.96, 54.67,4.92, 0.53 and 0. 72 mg/kg, respectively. （2） The over standard rates of Cu, Zn, Cr, Se, Cd and Pb in wheat bran were 100.00%, 54.55%, 81.82%, 9.09%, 45.45% and 72.73%, respectively; and the means of over standard samples was 16.01,62.00, 13.96, 0.82, 0.42 and 1.99 mg/kg, respectively. The over standard rates of Cu, Zn, Cr, As, Se, Cd and Pb in rice bran were 83.33% , 16.67% , 83.33% , 83.33%, 16.67% , 66.67% and 100.00% , respectively; and the means of over standard samples were 11.48,64.00, 5.37, 1.05,0.32, 0.23 and 19.57 mg/kg, respectively. （3） The over standard rates of Cu, Zn, Cr, As, Se and Pb in corn germ meal were 25.00%, 37.50%, 75.00%, 12.50% , 25.00% and 50.00%, respectively; and the means of over standard samples were 13.50, 64.00, 6.10, 1.82, 0.46 and 1.66 mg/kg, respectively. The over standard rates of Cu, Cr and Se in corn gluten meal were 11.11%, 55.56% and 55.56%, respective- ly; and the means of over standard samples were 11.40, 1. 56 and 0.94 mg/kg, respectively. The over standard rates of Zn, Cr and Pb in corn bran with syrup were 44.44%, 77.78% and 55.56%, respectively; and the means of over standard samples were 57.50, 6.13 and 1.65 mg/kg, respectively. The over standard rates of Cu, Zn, Cr, Se, Cd and Pb in DDGS were 33.33%, 58.33%, 66.67%, 8.33%, 8.33% and 66.67%, respectively; and the means of over standard sample were 11.75, 62.57, 5.57, O. 30, 0.62 and 4.47 mg/kg, respectively. （4） The over standard rates of Cr and Se in soybean meal was 15.00% and 25.00%, respectively; and the means of over standard sample were 3.90 and 1.63 mg/kg, respectively. The over standard rates of Cr, Se and Pb in cottonseed meal were 40.00%, 30.00% and 15.00%, respectively; and the means of over standard samples were 3.43, 1.18 arid 3.14 mg/kg, respectivcly. The over standard rates of Cr, As, Se, Cd and Pb in rapeseed meal were 81.82%, 18.18%, 45.45% , 9.09% and 72.73%, respectively ; and the means of over standard samples were 7.48, 2.22, 0.36, 0.24 and 4.91 mg/kg, respectively. [ Conclusions] The heavy metal pollution is more serious in grain by-products and cottonseed meal; the contents of Cr and Pb in feed ingredient are seriously excessive, which is potentially dangerous, and should be paid great attention.

Effects of Microbial Fermentation Feeds on Growth Performance of Weaned Piglets

[ Objective] TO study the effects of microbial fermentation feeds on growth performance of piglets, and provide the basis for their promotion and application, [ Method ] All of 60 Duroc x Landrace x Yorkshire crossbred weaned piglets, weighing 8-10 kg, were randomly housed in six groups, 10 piglets in each group. The piglets in control groups were fed with traditional daily food which contained aureomycin at 70 mg/kg . BW and concentrate feeds without antibiotics. While the piglets in experimental groups were fed with concentrate feeds without antibiotics and microbial fermentation feeds. [ Result] The results indicated that the average daily gain of experimental groups raised by 5.56%, and the feed conversion ratio reduced by 3.53% compared to control group. Moreover, the number of probiotics in the feces of experimental groups increased and pH value decreased significantly compared with the control groups （P 〈 0.05）. [ Conclusion] Microbial fermentation feeds can be used to replace antibiotics feeds, and promote healthy growth of the piglets.