Low crude protein formulation with supplemental amino acids for its impacts on intestinal health and growth performance of growing-finishing pigs

Background Low crude protein(CP)formulations with supplemental amino acids(AA)are used to enhance intestinal health,reduce costs,minimize environmental impact,and maintain growth performance of pigs.However,extensive reduction of dietary CP can compromise growth performance due to limited synthesis of non-essential AA and limited availability of bioactive compounds from protein supplements even when AA requirements are met.Moreover,implementing a low CP formulation can increase the net energy(NE)content in feeds causing excessive fat deposition.Additional supplementation of functional AA,coupled with low CP formulation could further enhance intestinal health and glucose metabolism,improving nitrogen utilization,and growth performance.Three experiments were conducted to evaluate the effects of low CP formulations with supplemental AA on the intestinal health and growth performance of growing-finishing pigs.Methods In Exp.1,90 pigs(19.7±1.1 kg,45 barrows and 45 gilts)were assigned to 3 treatments:CON(18.0%CP,supplementing Lys,Met,and Thr),LCP(16.0%CP,supplementing Lys,Met,Thr,Trp,and Val),and LCPT(16.1%CP,LCP+0.05%SID Trp).In Exp.2,72 pigs(34.2±4.2 kg BW)were assigned to 3 treatments:CON(17.7%CP,meeting the requirements of Lys,Met,Thr,and Trp);LCP(15.0%CP,meeting Lys,Thr,Trp,Met,Val,Ile,and Phe);and VLCP(12.8%CP,meeting Lys,Thr,Trp,Met,Val,Ile,Phe,His,and Leu).In Exp.3,72 pigs(54.1±5.9 kg BW)were assigned to 3 treatments and fed experimental diets for 3 phases(grower 2,finishing 1,and finishing 2).Treatments were CON(18.0%,13.8%,12.7%CP for 3 phases;meeting Lys,Met,Thr,and Trp);LCP(13.5%,11.4%,10.4%CP for 3 phases;meeting Lys,Thr,Trp,Met,Val,Ile,and Phe);and LCPG(14.1%,12.8%,11.1%CP for 3 phases;LCP+Glu to match SID Glu with CON).All diets had 2.6 Mcal/kg NE.Results In Exp.1,overall,the growth performance did not differ among treatments.The LCPT increased(P<0.05)Claudin-1 expression in the duodenum and jejunum.The LCP and LCPT increased(P<0.05)CAT-1,4F2hc,and B0AT expressions in the jejunum.In Exp.2,overall,the VLCP reduced(P<0.05)G:F and BUN.The LCP and VLCP increased(P<0.05)the backfat thickness(BFT).In Exp.3,overall,growth performance and BFT did not differ among treatments.The LCPG reduced(P<0.05)BUN,whereas increased the insulin in plasma.The LCP and LCPG reduced(P<0.05)the abundance of Streptococcaceae,whereas the LCP reduced(P<0.05)Erysipelotrichaceae,and the alpha diversity.Conclusions When implementing low CP formulation,CP can be reduced by supplementation of Lys,Thr,Met,Trp,Val,and Ile without affecting the growth performance of growing-finishing pigs when NE is adjusted to avoid increased fat deposition.Supplementation of Trp above the requirement or supplementation of Glu in low CP formulation seems to benefit intestinal health as well as improved nitrogen utilization and glucose metabolism.

Antibacterial Activity of Bacillus subtilis and Properties of Protein Crude Extract

In order to get biological drugs with no resistance or toxic side effects and to reduce the use of antibiotics, a strain of Baci//us subtilis was isolated from animal intestine, and the isolate was identified by molecular biological method; in vitro an- tibacterial test of the isolate was performed using agar diffusion method; the optimal fermentation condition of the isoJate was screened by conventional culture method; the antibacterial crude protein of the isolate was extracted by saturated ammonium sulfate method; the physicochemical properties of antibacterial crude protein was de- tected by comparison method; The results showed that the isolate was B. subti/is, which had antibacterial effects on Staphy/ococcus aureus, streptococcus and swine erysipelas. The fermentation effect of the isolate was the best under the condition of temperature 30 ~C, pH 7, liquid volume 75 ml/250 ml, inoculation volume 20% and culture time 48 h. The antibacterial effect of the isolate was the best when extract- ed by 80% saturated ammonium sulfate. The antibacterial crude protein had strong resistance to heat and acid. Organic solvent and UV irradiation had some influences on antibacterial crude protein. Proteases had hydrolytic effects on antibacterial crude protein. The isolated B. subti/is can be used to prevent and control the diseases caused by S. aureus, streptococcus and swine erysipelas, and can regulate intesti- nal microecology by adding into expanded feeds.

Effects of Powdery Mildew on 1 000-Kernel Weight, Crude Protein Content and Yield of Winter Wheat in Three Consecutive Growing Seasons

In order to clarify the impact posed by wheat powdery mildew （Blumeria graminis f. sp. tritici） on the yield and yield components in different epidemic seasons, field trials were conducted in three growing seasons, 2009-2010, 2010-2011 and 2011-2012, in Langfang City, Hebei Province, China. The relationships between 1000-kernel weight, crude protein content of grain and yield and disease index （DI）, as well as area under disease progress curve （AUDPC） were studied. The models of the percentage of loss of 1000-kernel weight, crude protein content and yield were constructed using DI at critical point （CP） of growth stages （GS） and AUDPC in the three growing seasons, respectively. The CPs for estimating 1 000-kernel weight, crude protein content of grain and yield of wheat caused by powdery mildew were GS 11.1, GS 10.5.3 and GS l 0.5.3, respectively. Models based on DI at CP to estimate the percentage of loss of 1000-kernel weight, crude protein content of grain and yield were better than models based on AUDPC. And models of the percentage of loss of 1000-kernel weight, crude protein content and yield for 2011-2012 season were significant different from these for 2009-2010 and 2010-2011 seasons. These results indicated that besides powdery mildew, weather conditions also had influence on 1 000-kernel weight, crude protein content of grain and yield loss of wheat when powdery mildew occurred.

Effects of Different Dietary Crude Protein Levels on Reproductive Performance in Breeder Roosters

[Objective] To investigate effects of different dietary crude protein levels on reproductive performance and find out the optimal additive proportion of crude protein. [Method] A total of 45 New Yangzhou breeder roosters at 21 weeks old were sampled and divided into three groups, namely, low-protein diet group, medium-protein diet group and high-protein diet group. They were fed with diets respectively at crude protein levels of 17.23%, 13.04% and 11.32%. The sperm volume, testicular traits and levels of reproductive hormones were analyzed during the whole repro- ductive period. [Result] The sperm volume, sperm motility and sperm density of the medium-protein diet group were higher than that of the other two groups, and the sperm deformity rate of the medium-protein diet group was lowest. The rooster＇s testicular traits including weight, volume and testis indexes were not significantly affected by different protein levels, but the testis shrank slowly with aging （ P 〈 0.05）. The levels of testosterone （T）, luteinizing hormone （LH） and follicule stimulating hormone （FSH） in plasma were respectively 6.34%, 19.64% and 3.88% higher in the lowprotein diet group than in the medium-protein diet group, and these indexes were respectively 7.20%, 17.54% and 9.84% higher in the low-protein diet group than in the high-protein diet group. But all these differences were not significant. [ Conclusion] The breeder roosters fed with the diet at the crude protein level of 13.04% show better reproductive performance and economic efficiency.

Prediction of Crude Protein in Ramie by Near-Infrared Spectroscopy(NIR)

[Objective] This study was conducted to evaluate the feasibility of deter- mining crude protein in ramie using near-infrared （NIR） spectrometer. [Method] Par- tial least square regression （PLSR） was performed to establish a calibration model based on 50 samples for predicting the crude protein content in ramie, and the model was validated with data in the validation set consisting of 10 samples. [Result] The correlation coefficient of the model was 0.98. There was a good correla- tion between the predicted values by the near-infrared prediction model and the measured values by chemical analysis, and the relative error was 3.54% on aver- age between the predicted and the measured values. [Conclusion] The results showed that it is feasible to determine crude protein content in ramie using NIR spectroscopy-based prediction model.

Rumen Degradation Regularity of Dry Matter and Crude Protein of Common Roughage in Beef Cattle

Three individuals of Horqin yellow cattle equipped with permanent fistula, weighed （548 ±21） kg, were sdected as the experimental animals. The ru- men degradation characteristics of dry matter （DM） and crude protein （CP） of roughage at 6, 12, 24, 48 and 72 h were measured by nylon bag method. The re- suits showed that the effective degradation rates of DM and CP of alfalfa hay were the highest, while higher contents of rapid degradation part and potential degrada- tion part of DM and CP also resulted in higher degradation rates of DM and CP. The effective degradation rates of CP and DM of roughage presented strong positive correlation with CP, but showed strong negative correlation with neutral detergent fiber （NDF）. The effective degradation rates of CP of five roughages successively were alfalfa hay 〉 alfalfa block 〉 ryegrass 〉 silage corn 〉 straw.

Effects of Dietary Metabolizable Energy and Crude Protein Levels on Reproductive Performance of Magang Geese

[ Objective] To investigate the effects of different levels of metabolizable energy and crude protein on egg laying performance and hatch- ing efficiency in Magang geese. [Method] The healthy Magang geese at 2 years old were randomly assigned into four groups, group Ⅰ, group Ⅱ, group Ⅲ and control group. They were fed with diets at different levels of metabolizable energy and crude protein, and then their eggs were collect- ed and hatched. During the test, their health was observed, and the egg weight, egg yield and hatching rate were recorded. [ Result] The average egg laying rates and average egg weight were significantly higher in the group Ⅰ, group Ⅱ and group Ⅲ than in the control group. The hatchable egg rates and egg fertilization rates of the group Ⅰ, group Ⅱ and group Ⅲ were also increased, and significance was found between the group Ⅲ and the other group （P 〈 0.05）. The feed costs of the three test groups were lower than that of the control group, and the feed cost was higher in the group Ⅲ than that in the group Ⅰ and Ⅱ. [ Conclusion] The levels of metabolizable energy and crude protein in diet have significant effects on laying performance and hatching efficiency in Magang geese.

Effects of NaOH Treatment on Fiber, Crude Protein and Soluble Sugar Content of Corn Straw

[Objective] The paper was to study the effects of different levels of NaOH on fiber, crude protein and soluble sugar content of cornstraw. [Method] Four treatments were designed in the test, namely control group, group 1, group2 and group 3, which were added with 0, 2%, 3%and 4% NaOH according to the dry weight of corn straw, and the moisture of corn straw after treatment was 45%. After being treated at room tem-perature for 48 h, sensory evaluation and nutrient composition analysis were performed for each group, and the contents of neutral detergent fiber（NDF）, acid detergent fiber （ADF）, crude protein （CP） and soluble sugar （SS） were measured. [Result] With the increasing addition level of NaOH,the content of NDF and ADF decreased gradually, and significant differences were observed between group 3 （adding 4% NaOH） and control group（P〈0.05）. There was no significant difference in CP content among treatment groups（P〉0.05）; the SS content gradually increased, and there weresignificant differences between treatment groups and control group （P〈0.05）. [Conclusion] 4% NaOH reduced the fiber content and increased thesoluble sugar content of corn straw.

Effect of Metabolic Excesses from Dietary Proteins on Blood Profile of Heat-stressed Broilers

Although,dietary proteins play a crucial role in poultry profit maximization,through the sustenance of birds`welfare,growth and development,yet metabolic excesses from crude protein(CP)degradation is detrimental to broiler chickens(BC)affected by heat stress.This study evaluated the effect of dietary protein levels on blood profile of heat-stressed BC at starter phase(SP)and finisher phase(FP).Arbor Acre BC(n=288)were randomly allotted to four dietary treatments(T1-23%CP;T2-21%CP;T3-19%CP;and T4-17%CP)with six replicate groups in a completely randomized design.Data were subjected to descriptive analysis,analysis of variance(p=0.05)and correlation statistics.Protein intake(PI)was not significantly affected by varying CP in diets at SP,but not at FP,where PI significantly increased with increasing dietary CP.PER had a negative correlation with PCV(r=-0.89,p<0.01),Hb(r=-0.88,p<0.01),RBC(r=-0.93,p<0.01)and PI(r=-0.78,p<0.01).Metabolic excesses including heat dissipation from dietary proteins influenced PCV,Hb,platelets and glucose of heat-stressed broilers.

Agronomic Trait and Protein Component of F_2 Hybrid Originated from Intergeneric Somatic Hybridization Between Triticum aestivum and Agropyron elongatum

Protoplasts derived from common wheat (Triticum aestivum L,. cv. Jinan 177) were fused with UV-treated protoplasts of Agropyron elongatum. (Host) Nevski by PEG method, and fertile asymmetric somatic hybrid plants resembling wheat morphology were obtained. The F-2 hybrid plants could be divided into 3 types according to their morphology. Type I hybrids had high and loosely standing stalks with big spikes and grains. Type ii hybrids were dwarf and compact in shape with high tillering ability and smaller spikes. Type III hybrids were similar to type I as a whole but had more compact and erect spikes. All the F-2 hybrid lines were superior to wheat in seed protein content, although some difference existed between themselves. Protein analysis of immature embryos and flag leaves from hybrids by two-dimensional electrophoresis showed that they possessed characteristic proteins of both parents and some new proteins. There existed also some different kinds of proteins in different lines.

Quality Analysis and Evaluation of Maize Cultivars Approved by Shanxi Province

[Objective] This study aimed to provide a theoretical basis for the genetic improvement of maize quality in Shanxi Province. [Method] The variations in unit weight, crude starch content, crude protein content, crude fat content and lysine content of maize cultivars approved by Shanxi Province during 2003-2012 were analyzed. [Result] In Shanxi Province, the average unit weight and crude starch content of maize cultivars approved during 2003-2012 were trended to be increased;the crude fat contents of maize cultivars approved during 2003-2012 showed no significant changes; the lysine contents of maize cultivars approved during 2003-2008 were essentially unchanged; the crude protein contents of maize cultivars approved during 2003-2012 declined slightly. [Conclusion] The crude starch content and unit weight of maize increased with the increased yield; the crude protein content, crude fat content and lysine content showed certain stability, and they were mainly controlled by genes. Therefore, the breeding of particular maize should be strengthened.

Assimilating efficiency of soil nutrition of Phalaris arundinacea L.

Phalaris arundinacea L. is fine perennial herbage of Gramineae. Eight treatments including N, P, K, NP, NK, NPK, PK and controls were done for studying its absorbing efficiency of soil nutrition. At tillering stage, the coefficient of absorbing and utilizing of N, P, and K from soil and fertilizer were analyzed according to M.K. Kaeomobk抯 formula and the contents of crude protein and fat were also measured. The yields of fresh crop, hay and seed were measured at ripening stage. For N absorbing coefficient of Ph. arundinacea from soil (Kn%), the composition PK treatment is best (12.36%) and K treatment is worse, while for N absorbing coefficient from fertilizer (Ky%), all the treatments are higher than control but the composition NPK treatment presented the highest (14.78%). For the absorbing coefficient of P from soil (Kn%), composition NK treatment is highest (19.30%), but K treatment was lower than control, while for that of P from fertilizer (Ky%), all the treatment were higher than control but the composition NP treatment showed the highest (19.52%). As to K absorbing coefficient from soil (Kn%), NP treatment is the best (19.2%) and single P treatment is worst, while for that (Ky%) of K from fertilizer the composition NPK treatment was best (28.44%). As concerns treatments for the outputs of fresh and dry crop, the composition NP treatment was best and all the treatment were higher than control. The composition NK treatment produced highest yield of seed and highest content of crude protein as compared to other treatments. For content of crude fat, the compositions NK and N treatments are best. The experiment indicates that application of fertilizer at proper proportions could increase the yield of Ph. Arundinacea and raise the utilizing efficiency of nourishment element from soil and fertilizer.

Advances in low-protein diets for swine

Recent years have witnessed the great advantages of reducing dietary crude protein(CP) with free amino acids(AA)supplementation for sustainable swine industry, including saving protein ingredients, reducing nitrogen excretion, feed costs and the risk of gut disorders without impairing growth performance compared to traditional diets. However, a tendency toward increased fatness is a matter of concern when pigs are fed low-protein(LP) diets. In response, the use of the net energy system and balanced AA for formulation of LP diets has been proposed as a solution. Moreover, the extent to which dietary CP can be reduced is complicated. Meanwhile, the requirements for the first five limiting AA(lysine, threonine, sulfur-containing AA, tryptophan, and valine) that growing-finishing pigs fed LP diets were higher than pigs fed traditional diets, because the need for nitrogen for endogenous synthesis of non-essential AA to support protein synthesis may be increased when dietary CP is lowered. Overall, to address these concerns and give a better understanding of this nutritional strategy, this paper reviews recent advances in the study of LP diets for swine and provides some insights into future research directions.

Rumen fermentation and bacterial communities in weaned Chahaer lambs on diets with different protein levels

We evaluatedthe effects of diets with different crude protein （CP） levels on growth performance, rumen fermentation and bacterial communities in weaned Chahaer lambs. 128 weaned Chahaer lambs （（20.56±1.43） kg body weight; ram：ewe 1：1） aged （61±1.85） d were randomly alotted to one of four diets with CP content of 11.17% （T1）, 12.06% （T2）, 13.40% （T3） or 14.36% （T4）.Ruminal fermentation parameters were measured and bacterial communities were analysed using PCR-dena-turing gradient gel electrophoresis （PCR-DGGE） and quantitative PCR. The average daily gain and feed utilization efifciency in T3 were higher than those in the other groups （P〈0.05）, although the dry matter intake and metabolizable energy intake were similar. Total volatile fatty acid concentration in the ruminal lfuid of T3 was lower than that of T1 （P=0.011）, T2 （P=0.008） or T4 （P=0.309）. The ammonia nitrogen concentration and acetate/propionate ratio of ruminal lfuid were signiifcantly higher in lambs fed the higher CP diets, whereas the molar concentrations of propionate and butyrate of ruminal lfuid were lower. The rumen bacterial community was similar in T2 and T3 which shown more stable and diverse rumen microbes ecosystem compared with the other groups. The DGGE proifles and phylogenetic tree indicated thatBacteroides uniformis,Clostrid-iumalkalicellulosi,Alkalibaculum bacchiandSaccharofermentanssp.were common bacterium of Chahaer lamb rumen. B. uniformis,C.alkalicelulosi,Saccharofermentanssp. andGracilibacter thermotolerans,which belong to the Bacteroidetes and Firmicutesphyla,were the dominant species in the rumen of lambs fed 13.40% CP.However,Ruminococcus albus, Ruminococcus lfavefaciensand Butyrivibrio ifbrisolvenswerenot differentin lambs fed different CP diets. Therefore, it could be concluded thatB. uniformis,C.alkalicelulosi,A. bacchiandSaccharofermentanssp.were common bacteria of Chahaer lamb rumen. Furthermore, the dietary CP of 13.04% could improve performance and change rumen fermentation model by increasing the dominant species’ peak intensities ofB. uniformis,C.alkalicelulosi,Saccharofermentanssp. and Gracilibacter thermotoleransand stabilizing rumen microbial ecosystem.

The Effect of Wheat Mixtures on the Powdery Mildew Disease and Some Yield Components

Mixtures composed of five wheat cultivars,Jingshuang 16,Jing 411,Jingdong 8,Lunxuan 987,and Baofeng 104,with different levels of resistance against powdery mildew were tested for their potential containment of the disease development in the field and for the influence on grain yield and the content of crude protein in the years 2007 and 2010.The plots were inoculated artificially with mixed isolates collected in the fields and propagated in the greenhouse and the disease was scored in 7 d interval during the two growing seasons.It was indicated that certain combinations,e.g.,Jingdong 8：Lunxuan 987,Jingdong 8：Baofeng 104,and Jing 411：Jingdong 8：Baofeng 104,showed positive efficacy on the mildew.The cultivar combinations tested in 2007 showed increase of grain yield,while most of the combinations tested in 2010 did not show the increase.The differences of the increases or decreases were not statistically significant except combinations Jing 411：Jingdong 8：Baofeng104,Jingshuang16：Jingdong8：Lunxuang 987 and Jingshuang 16：Jingdong 8：Lunxuan 987：Baofeng 104,which showed the decrease of the grain yield.The mixtures did not show influence on the content of crude protein in grain.More cultivar combinations need to be tested.

Dietary branched-chain amino acid assessment in broilers from 22 to 35 days of age

Background:Valine and isoleucine are similar in chemical structure and their limitation in broiler chicken diets.To evaluate their limitation and interactive effects,multivariate assessment nutrition studies for the branched-chain amino acids(BCAA)are needed.A three level(−1,0,+1),three-factor Box-Behnken design study was conducted to assess dietary BCAA ratios to lysine of 65,75,and 85 for valine,58,66,and 74 for isoleucine,and 110,130,and 150 for leucine in male and female Lohman Indian River broilers from 22 to 35 d of age.Results:Live performance of male broilers was not affected by BCAA level.However,male broilers fed increasing isoleucine had improved(P=0.07)carcass yield as leucine and valine were reduced.Female broilers had improved body weight gain(P=0.05)and feed conversion(P=0.003)when leucine and isoleucine were at their lowest levels,independent of valine,but increasing leucine impaired live performance and warranted concomitant increases in isoleucine to restore responses.Increasing dietary isoleucine and valine in female broilers increased breast meat yield(P=0.05),but increasing leucine tended to diminish the response.Conclusion:The female Lohman Indian River broiler is more sensitive to BCAA diet manipulation than males.Specifically,as dietary leucine is increased in female broilers,dietary isoleucine increases were needed to offset the negative effects.Both increases in dietary valine and isoleucine improved breast meat yield in female broilers,but only when birds were fed the lowest dietary leucine.

Overload type and optimization of meadow carrying capacity in Maqin County in the Three-River Source Region,China

Alpine meadows,comprising the main ecosystem of the Three-River Source Region,play an important role in the economic development of western pastoral areas.To determine whether the grazing level was too intense or the nutrient-carrying capacity of the meadows was overloaded,and to offer solutions in Maqin County,Qinghai Province,China,the meadows carrying capacity was determined by combining grass-yield and nutrients data for different seasons across different meadows.The results showed that the levels of crude protein(CP),ether extract(EE),ash,soluble sugars(SS),gas production,and energy value of forage in the summer–autumn grazing meadows were higher than those of the winter–spring meadows.Neutral detergent fiber(NDF)and acid detergent fiber(ADF)of forage in the summer–autumn grazing meadows were lower than those of the winter–spring meadows.We found that no pastures were overloaded with metabolizable energy(ME)for the whole year but digestible crude protein(DCP)was overloaded in winter–spring.And there were differences in the amount carrying capacity(forage yield)of seasonal grazing meadows for the different herds,the overload types were annual overloading(herd A),overloaded in summer–autumn(herd B),overloaded in winter–spring(herd C),and not overloaded(herd D).Compared with the previous grazing mode,theoretical carrying capacity,DCP carrying capacity,and ME carrying capacity of herd A increased by 20,19,and 27 sheep units,respectively,after optimization;herd B:36,31,and 45 sheep units,respectively;herd C:28,23,and 44 sheep units,respectively;and herd D:43,40,and 61 sheep units,respectively.In the Three-River Source Region and similar alpine pastoral areas,the grassland-livestock structure should be optimized to improve grassland vegetation status and increase the theoretical carrying capacity.

Energy and Protein Requirements for 0-to 4-Week-Age Gushi Chicks

In this experiment, 540 male and female chicks of 1-day-age were selected respectively and reared separately. 3×3 factorial experiment was designed. Gushi chicks were fed with nine diets under different metabolizable energy (ME) and crude protein (CP). Effects of different diets on the performances and carcass ingredients of 0-to 4-week-age Gushi chicks were studied by rearing, comparative slaughter and metabolism experiments. Based on the results of three experiments, ME intake per kilogram metabolic weight was regarded as dependent variable (Y) ,and its corresponding net energy (NE) deposition per kilogram metabolic weight was regarded as independent variable (X) , respectively. Lineal regressive analysis was made according to the mathematic model: Y=a+bX. Maintenance ME( MEm) and the converted coefficient from net energy for gain( NEg) to ME for gain( MEg) were found out, then ME requirement was divided into MEm+ MEg, which is ME=359.14 W0.75+ 10.47△W; CP intake and corresponding metabolic weight were regarded as dependent variable and independent variable respectively, and then regressive analysis was made. The result was CP=0. 57 + 8. 21 W0.7S. Consequently, average daily gain (ADG), average daily feed intake and metabolic weight were put into the regressive equations, and then ME and CP requirements for 0- to 4-week-age Gushi chicks were obtained, 12.38 MJ kg-1 and 20.13%, respectively, the ratio of CP to ME was 16. 26 g MJ-1.

Optimization of South China 5 Cassava-Leucaena Protein Feed Production by Kombucha in Solid-State Fermentation

[Objective] To optimize solid-state fermentation of South China 5 （SC5） cassava-leucaena protein feed by kombucha. [Method] The SC5 cassava-leucaena protein feed was fermented by kombucha. The fermentation conditions were optimized. [ Result] The optimum conditions of solid-state fermentation were as follows： cassava and leucaena weight ratio, 7：3; fermentation time, 6 d; kombucha volume, 10 ml; fermentation temperature, 30 ℃; and water volume, 200 ml. The content of crude protein in feed was substantially increased and reached 23.64%. [ Conclusion] The optimized fermentation process greatly improves utilization of the SC5 cassava-leucaena protein feed.

Analysis of Some Important Forage Quality Attributes of Southeastern Wildrye (Elymus glabriflorus) Using Near-Infrared Reflectance Spectroscopy

Southeastern wildrye (Elymus glabriflorus, Vasey ex L.H. Dewey) is a cool-season, perennial grass native to southeastern United States. Recently, there is a growing interest in its development as a grazing and haying forage crop due to its wide area of adaptation across this region. Consequently, there is a great need for the evaluation of its forage quality by rapid, but accurate analytical methods like Near-Infrared Reflectance Spectroscopy (NIRS). In this study, acceptable NIRS calibration models were developed for: dry matter, DM (n = 113, R2 = 0.904, RSCD = 2.54, RSCIQ = 4.65);crude protein, CP (n = 113, R2 = 0.974, RSCD = 5.16, RSCIQ = 5.92);acid detergent fiber, ADF (n = 116, R2 = 0.896, RSCD = 2.35, RSCIQ = 1.28);neutral detergent fiber, NDF (n = 118, R2 = 0.934, RSCD = 2.53, RSCIQ = 3.38);digestible dry matter, DDM (n = 116, R2 = 0.895, RSCD = 2.36, RSCIQ = 1.35);dry matter intake, DMI (n = 115, R2 = 0.924, RSCD = 2.40, RSCIQ = 2.53);and relative feed value, RFV (n = 114, R2 = 0.932, RSCD = 2.94, RSCIQ = 2.81). Prediction of independent validation sets yielded good agreement between the NIRS predicted values and the laboratory reference values for each of: DM (n = 53, R2 = 0.831, RPD = 2.45, RPIQ = 4.24);CP (n = 57, R2 = 0.967, RPD = 5.37, RPIQ = 7.16);ADF (n = 49, R2 = 0.895, RPD = 2.97, RPIQ = 1.51);NDF (n = 53, R2 = 0.928, RPD = 3.75, RPIQ = 4.22);digestible dry matter, DDM (n = 55, R2 = 0.860, RSCD = 265, RSCIQ = 1.15);dry matter intake, DMI (n = 156, R2 = 0.845, RSCD = 2.48, RSCIQ = 2.11);and relative feed value, RFV (n = 55, R2 = 0.916, RSCD = 3.45, RSCIQ = 3.04) contents, indicating that all seven calibration models had good quantitative information. Therefore, precise, accurate, and rapid analysis of these important forage quality attributes of southeastern wildrye can be routinely done using the developed NIRS calibration models.