Effects of Supplemental Histamine on Gastric Acid Secretion, Digestive Enzyme Activities, Intestinal Microfloral of Early Weaned Piglets

Two experiments were conducted to study the effect of supplemental histamine in the diet ofearly-weaned piglets. In experiment A, 24 cross bred piglets with an average body weight of 6.10±0.40 kg,weaned at the age of 28 days, were divided into four groups, fed with basal diet of low dietary copper without(control) or with supplemental histamine at 60, 120, 180 μg kg-1 BW. During the two weeks and the thirdweek after weaning, ADG(average daily gain) of piglets were increased by 15.8% (P＜0.05), 9.5% (P＜0.10) by addition of 60 μg kg-1BW histamine, but decreased by addition of 180 μg kg-1BW histamine, whichalso increased the amount of E. coli in colon and the scour incidence. The secretion of gastric acid and pepsinwere improved by both dose of supplemental histamine (60, 180 pg kg-1BW) and gastric digesta pH were de-creased by both. Addition of 60 μg kg-1 BW histamine improved the activities of trypsin, amylase in duodelumdigesta. In experiment B, 12 cross bred piglets with an average body weight of 6.85±0.35 kg, weaned at theage of 28 days, were divided into two groups, fed with basal diet of high dietary copper without (control) orwith supplemental 60 μg kg-1 BW histamine. During the two weeks and the third week after weaning, ADG ofpiglets were increased by 9.8% (P＜0.05), 7.0% (P＜0.10). The secretion of gastric acid, activities oftrypsin and amylase in duodelum digesta, were also improved by addition of 60 μg kg-1 BW histamine. The re-sults showed that addition of histamine (60 μg kg-1 BW) in early weaned piglets could increase the secretion ofgastric acid and pepsin, reduce gastric digesta pH and scour incidence, improve activities of trypsin, amylasein duodelum digesta, and the growing performance of early weaned piglets.     

Effects of conditioners (single-layer,double-layer and retention-conditioner) on the growth performance,meat quality and intestinal morphology of growing and finishing pigs

This experiment was conducted to investigate the effects of feed conditioners(single-layer, double-layer and retentionconditioner) on the growth performance, meat quality and intestinal morphology of pigs throughout the growing to finishing phase. A total of 96 growing pigs((28.70±3.20) kg) were selected and randomized into three treatment groups with four replicates per group. Eight pigs were used per replicate for the 17-week feeding trial. The grower diet was given at 0 to 6 weeks and a finisher diet was given at 6 to 17 weeks. The treatments were as follows: SC diet(control; single-layer conditioning), DC diet(double-layer conditioning), and RC diet(retention-conditioning). Starch gelatinization was significantly higher(P0.05) in the RC treatment than in the SC treatment, however, there was no significant difference in the starch gelatinization between the DC group and the RC group. In the growing phase, the feed to gain index(F:G) was significantly lower(P0.05) in the RC group than in the SC and DC groups. Between growing and finishing, the F:G was the lowest(P0.05) in the SC group compared to the RC or DC group. Drip loss, a measurement of meat quality, was significantly lower(P0.05) in longissimus dorsi tissue collected from pigs fed the RC diet than in tissues collected from pigs fed the SC diet. The intestinal quality of the duodenum and jejunum tissues showed a significant increase(P0.05) in the crypt depth and villus height in the RC group compared to the SC-or DC-treated pigs. These results demonstrated that the retentionconditioner treatment decreased the F:G in growing pigs, improved intestinal morphology and enhanced the meat quality in the finishing pigs. However, the retention-conditioner treatment had a negative impact on growth performance in the finishing pigs.     

Effects of Lard Enriched with n-3 Polyunsaturated Fatty Acids on Serum Lipid Composition in Rats

This study evaluated the lard enriched with n-3 polyunsaturated fatty acids(PUFAs) on serum lipid composition in rats.The experiment contained two parts:(A) 20 crossed pigs(Landrace×Min, 60±2 kg) were assigned randomly into two dietary groups: a control group and a group fed the diet added 10% linseed based on the control diet.This part lasted 56 days and the results showed that the levels of the total n-3 PUFA in lard were improved approximately 2-fold(p0.05), when pigs were fed 10% flaxseed compared to a control diet of corn.The lard taken from pigs was melted and preserved for rat experiment;(B) 45 Sprague-Dawley rats at day 36 were randomly fed one of three diets for 42 days: the diet without added fat, the diet contained 10% common lard from pigs fed a conventional corn ration and the diet contained 10% lard enriched with n-3 PUFA from pigs fed 10% flaxseed.Rats fed lard significantly increased(p0.05) serum cholesterol levels compared with rats maintained on a diet without lard.However, rats fed the lard enriched with n-3 PUFA significantly decreased the level of low-density lipoprotein cholesterol in serum(p0.05) and better hepatic antioxidant defense capacities, when compared with rats fed common lard(p0.05).The results showed that pigs fed diet with n-3 PUFA produced lard enriched with n-3 PUFA and thus provided positive health benefits to the consumers.     

Effect of Glutamine Supplementation on Abilities of Antioxidative and γ-glutamyl Transpeptidase Activities in Liver and Intestine of Piglets Fed Diets Containing Raw Soybean

Eighteen male piglets weaned at 28 days age were randomly assigned to one of three treatments(1% glutamate, 1% and 2 % glutamine supplementation). The basal diet contained 5 % raw soybean. The di-ets were calculated to be isonitrogenous and isoenergetic. The level of plasma glutahione (GSH) increasedmarkedly in piglets fed glutamine, and the response was related to dose. In treatments Ⅰ and Ⅱ, the levels ofplasma GSH were significantly higher than that in the control at the 35 days age (P＜0.05). The level of plas-ma GSH in treatment Ⅱ was significantly higher than that in the control at 42 days age (P＜0.05). At 49days age, there was no significantly difference of the level of GSH in plasma, liver, spleen, intestine and mes-enteric lymph node. The level of superoxide dismutase (SOD) in liver and spleen was higher than that of thecontrol, however, the difference wasn't significant. Dietary glutamine supplementation decreased γ-glutamyltranspeptidase(γ-GT) activities in liver. The activities of γ-GT of liver protein in treatment Ⅱ were signifi-cantly lower than that in the control (P＜0. 05). The activities of γ-GT of duodenum in treatments Ⅰ and Ⅱwere also significantly lower than that in the control (P＜0.05). But there were no significant differences ofthe activities of γ-GT in jejunum and ileum. The results showed that dietary glutamine supplementation in-creased the level of plasma GSH, and decreased γ-GT activities.     

Effect of graded levels of fiber from alfalfa meal on apparent and standardized ileal digestibility of amino acids of growing pigs

Two experiments were conducted to determine the effects of fiber level from alfalfa meal and sampling time on the apparent ileal digestibility(AID) and standardized ileal digestibility(SID) of amino acids(AA) in growing pigs. A total of 24 ileal-cannulated pigs(Duroc×(Large White×Landrace) with body weight(21.4±1.5) kg) were randomly allotted to 4 treatments. The pigs were provided a corn-soybean meal diet or a diet containing 5, 10 or 20% of alfalfa meal during two 10-d experimental periods. The AID of AA was measured. Six ileal-cannulated pigs were fed a protein-free diet in order to estimate the endogenous protein losses and SID of AA. Ileal AA digestibility was not affected by inclusion of 5 or 10% alfalfa meal in the diet(P0.05). The AID of His, Lys, Met, Phe, Thr, Val, Ala, Asp, Cys, Gly, Pro, Ser and Tyr reduced by 2.0–6.8% with the addition level of alfalfa meal(linear, P0.05). The SID of His, Lys, Ser, Thr and Tyr decreased by 2.2–4.3% as the level of alfalfa meal in the diet increased(linear, P0.05). The AID and SID of AA were not affected by the sampling time(P0.05). A multiple linear regression analysis, taking into account both the soluble and insoluble fiber content in the diets, explained more than 36% of variation in SID of Ser and Thr(P0.05). In conclusion, the corn-soybean meal diet containing 10% of alfalfa meal did not affect ileal AA digestion. The AID and SID of AA were similar between two sampling times. Increasing the concentration of total dietary fiber from 12.3 to 21.4% by adding graded levels of alfalfa meal(0–20%) to a corn-soybean meal control diet induced a linear reduction in AID and SID of most AA. Soluble and insoluble fibers from alfalfa meal have differential roles in the AA digestion, which may help explain the variation observed in the SID of partial AA. These findings would provide important information for dietary fiber level and composition related to AA digestion.     

Effect of dietary supplementation with mulberry (Morus alba L.) leaves on the growth performance,meat quality and antioxidative capacity of finishing pigs

The present study was conducted to evaluate the effect of dietary mulberry(Morus alba L.) leaves powder(MLP) supplementation on meat quality of finishing pigs.A total of 40 Duroc×Landrace×Yorkshire pigs(initial body weight of(40.5±0.63) kg) were randomly allotted into two treatments,fed either with control diet or 15% MLP diet for 85 d.The results showed that MLP diet decreased(P≤0.05) average daily gain(ADG) and increased(P0.05) feed/gain ratio(F/G) in the finishing and whole period.MLP diet also decreased(P0.05) carcass weight,dressing percentage,last rib and average backfat depth.However,MLP diet increased(P0.05) intramuscular fat(IMF) content,decreased(P0.05) shear force,cooking loss and drip loss.In addition,MLP diet increased(P0.05) total antioxidative capacity,glutathione peroxidase and tended(P0.10) to increase total superoxide dismutase in serum.In longissimus thoracis,myosin heavy chain(MyHC) I and IIa mRNA levels were increased(P≤0.05) for MLP diet.In conclusion,15% MLP supplementation reduced the growth performance and carcass traits,but improved meat quality of finishing pigs possibly through the change of myofiber characteristics,enhancement of antioxidative capacity and increase of IMF.     

Effects of Different Compound Trace Element Premixed Materials on Beef Cattle Production Performance and Anti-oxidation Capacity

In this study, the effects of two types of premixed materials with different combinations of trace elements on the production performance and antioxidant capacity of simmental beef cattle were examined.Fifteen healthy simmental beef cattle of similar weight(approximately 330 kg), the same age(12 months), without castration, and a good physique were divided into three groups, with five beef cattle in each group.Food of GroupⅠ beef cattle was supplemented with a commercially marketed 5% compound trace element premixture for fine beef cattle.Food of GroupⅡbeef cattle was supplemented with a 5% compound microelement premixture for beef cattle that was designed to address local nutrient deficiencies and surpluses.In the blank control group, the beef cattle were not fed a premixture.The pretest period was 15 days, and the test period was divided into prefattening(45 days) and postfattening(45 days) stages.Body weight and body size indices were recorded at 1, 2 and 3 months, and blood samples were collected regularly.In GroupⅠ, the daily weight gain increased significantly by 15.7% compared with that of the control group.The largest daily weight gain was in Group Ⅱ, which increased by 31.6% compared with that in the control.During the test period of 90 days, the body size indices of the three different groups increased in different months, with significant increases in the indices for both test groups compared with those of the control.In GroupⅠ, the activity of CP, the total activity of SOD and Cu-Zn-SOD increased significantly(p0.05) compared with those in the control group, with a highly significant increase observed in GSH-PX activity(p0.01).In GroupⅡ, the increases in the activity of CP and the total activity of SOD and Cu-Zn-SOD were highly significant compared with those in the control group(p0.01).In addition, a significant increase was observed in GSH-PX activity(p0.05).Based on pretest results, the concentrations of Cu, Zn, Mo, Mn, Se and Co in the blood of experimental beef cattle were lower than those of the normal range.After feeding for 90 days, the concentrations of Cu, Zn, Mo, Mn, Se and Co in the blood of GroupsⅠ andⅡ were significantly higher than those in the control group(p0.05).The concentrations of elements in the blood of Group II were close to the appropriate levels.Thus, the effects of the specifically designed compound microelement premixture on the prevention of nutrient imbalances and control of beef cattle nutrition metabolism and the production of fattened beef cattle were significant.     

Effects of high ambient temperature on lipid metabolism in finishing pigs

In this study,we investigated the effects of high ambient temperature on lipid metabolism in finishing pigs.Sixteen pigs((79.6±1.2) kg) were randomly assigned to two groups:(1) ambient temperature of 30℃ with ad libitum access to feed(HT;n=8) and(2) ambient temperature of 22℃ and fed the average amount consumed by eight pigs in HT group on the previous day(PF;n=8).After 21 days of constant exposure to different environmental conditions,all the pigs were euthanized,and blood and tissue samples were obtained.High ambient temperature increased the proportion of backfat(P=0.04,+21.6%)and flare fat(P0.01,+43.3%).Compared with pair-fed pigs,the activities of fatty acid synthase(FAS) and malic enzyme in backfat and flare fat were lower(P0.05) in heat-stressed pigs,as were the amounts of acetyl-CoA-carboxylase and FAS in the longissimus muscle(LM),the amount of FAS in backfat(P0.01),and FAS activity in the liver(P0.01).Ambient temperature did not affect the amount of hormone-sensitive lipase in different tissues.The amount of lipoprotein lipase in flare fat tended to be higher(P=0.09,+28.3%),and the activities of β-hydroxyacyl coenzyme A dehydrogenase in front and back of LM were lower(P0.01,-48.3 and-49.8%,respectively) at 30℃ than at 22℃.The plasma concentration of high-density lipoprotein tended to be lower(P=0.08),but the plasma concentrations of very low-density lipoprotein(VLDL)(P=0.09,+50.0%) and nonestesterified fatty acid(NEFA)(P=0.04,+44.2%) were higher in heat-stressed pigs.We concluded that high ambient temperature depressed de novo fatty acid synthesis in both adipose tissues and the liver.However,β-oxidation of fatty acid in skeletal muscles was also inhibited in the high-temperature environment.As a result,more plasma NEFAs were used to synthesize VLDLs in the liver and were absorbed by adipose tissues.This may be one reason that high ambient temperature enhances the accumulation of backfat and flare fat in finishing pigs.     

Effect of the Inclusion of Chestnut in the Finishing Diet on Volatile Compounds of Dry-Cured Ham from Celta Pig Breed

The effect of the inclusion of chestnut in pigs finishing diet on volatile compounds of dry-cured Celta ham was studied.Twelve hams of each type(from three different pigs finishing diets:concentrate(CO),mixed(MI)and chestnut(CH)) were used.Volatiles were extracted using a purge-and-trap method and analyzed by gas chromatography/mass spectrometry(GC/MS).Thirty-nine volatile compounds were identified in dry-cured Celta ham samples.Most abundant volatiles in ham samples were aldehydes,which represented respectively,53%(CO),51%(MI)and 46%(CH)of the total volatile composition.With the exception of 2-butenal,2-methyl,all aldehydes were affected by feeding system.On the other hand,hydrocarbons n-alkanes were the second major group in the volatile profile of dry-cured Celta hams and represented 28.9,35.7 and 32.4%of the total volatile composition for CO,MI and CH groups,respectively.Ham samples from chestnut group showed a higher content of alcohols and this result could be related with the inclusion of chestnut in the finishing diet of pigs.Principal component analysis showed a good separation among groups.The discriminant analysis selected eight variables(butanoic acid,hexanal,octanal,nonenal(E),decenal(E),tetradecane,decane trimethyl and pyridine 2-methyl) and calculated two discriminating functions to predict if chestnut has been included in the finishing diet.Thus,it was possible to discriminate between groups fed with finishing diets containing chestnuts in their composition(mixed and chestnut group).     

Response of Cytochrome P450 Expression to Maize Volatiles in Helicoverpa armigera (Hner)

The 7-ethoxycoumarin O-deethylase (ECOD) activities of cytochrome P450s and differential expression of six cytochrome P450 genes induced by the volatiles from both damaged and undamaged maize plants were investigated in the cotton bollworm, Helicoverpa armigera (Hner). The ECOD activity changed with time of exposure to maize volatiles. At 36 h after cotton bollworm larvae exposure to maize volatiles, the ECOD activities in cotton bollworm damaged and artificially damaged groups were 2.36 and 4.53 times higher than the control group respectively. The relative expression levels of CYP4S1, CYP6B2 and CYP6B7 in the cotton bollworm were significantly increased in artificially damaged plant group, which was 2.93, 5.09 and 10.66 times higher than that in the control group, respectively. The expression levels of CYP6B2, CYP6B6, CYP9A12, and CYP9A14 were much lower in the larvae exposure to volatiles from both healthy and pest damaged maize seedlings than in the control group at 12 h after larvae exposure to maize volatiles. For the cotton bollworm damaged maize group, the expression of CYP4S1 and CYP9A14 increased.     

Effects of dietary yeast β-glucan on nutrient digestibility and serum profiles in pre-ruminant Holstein calves

This study aimed to investigate the effects of dietary supplementation of yeast β-glucan on the nutrient digestibility and serum profiles in pre-ruminant Holstein calves. Forty-two neonatal Holstein calves((39.6±4.2) kg) were randomly allotted to six groups, and each was offered one of the following diets: a basal diet(control) or the basal diet supplemented with 25, 50, 75, 100 or 200 mg of yeast β-glucan kg–1 feed(dry matter basis). The basal diet consisted of a milk replacer and a starter feed. The trial lasted for 56 d. Two digestibility trials were conducted from d 14 to 20 and from d 42 to 48. Blood samples were collected on d 0, 14, 28 and 42 for serum profile analyses. On d 56, three calves from each group were slaughtered, and intestinal samples were collected to assess the villous height, crypt depth and mucosal thickness. Although feed intake was not affected by dietary treatment(P>0.05), the average daily gain(ADG) and gain-to-feed ratios were higher(P<0.05) for the calves fed 75 mg of yeast β-glucan kg–1 feed than those in the other groups. The supplementation of yeast β-glucan at 75 mg kg–1 feed increased the apparent digestibility of dry matter(DM), crude protein(CP), ether extract(EE), and phosphorus(P)(P<0.05) and the ratio of intestinal villous height to crypt depth(V/C)(P<0.05) when compared with the control group. No effects of yeast β-glucan on the serum concentrations of total protein(TP), albumin(ALB), serum urea nitrogen(SUN) and glucose(GLU) were observed(P>0.05). Compared with the control group, supplementation of yeast β-glucan decreased(P<0.05) the serum concentrations of triglycerides(TG) and total cholesterol(TC). The serum concentration of immunoglobulin G(Ig G) and immunoglobulin M(Ig M) increased quadratically(P<0.05), whereas the serum concentration of immunoglobulin A(Ig A) was unaffected by dietary treatments(P>0.05). The supplementation of yeast β-glucan stimulated the enzymatic activity of alkaline phosphatase(ALP)(P<0.05) compared with the control group. The lysozyme(LYZ) concentration increased quadratically(P<0.05) with increasing yeast β-glucan levels. The results suggested that dietary supplementation of yeast β-glucan at 75 mg kg–1 feed improved nutrient digestibility, enhanced immunity by increasing the immunoglobulin concentration and stimulating ALP, and exerted no adverse effects on metabolism in pre-ruminant calves.     

In Situ Determination of Iron Distribution and Oxidation State in Broiler Duodenal Wall by Synchrotron Radiation μ-XRF and μ-XANES

Micro-X-ray fluorescence (μ-XRF) and micro-X-ray absorption near edge structure (μ-XANES) have not been widely used in animal nutrition.In situ determination of iron distribution and oxidation state in broiler duodenal wall was done by μ-XRF and μ-XANES techniques.Fifty newly hatched healthy (1-day-old) Arbor Acres commercial male broilers were used in this experiment.The chicks were fed a corn-soybean meal basal diet (96.00 mg of Fe/kg diet) from the 1st day to the 21st day,but were fed a semi-purified diet (12.50 mg of Fe/kg diet) after 21 days to deplete the body Fe stores.On the 28th day,after an overnight fast,all the birds were randomly allotted to four different Fe sources [FeSO_4,Fe-Gly (II),FeCl_3 and Fe-Gly (Ⅲ)].Three points five mL nutrient solution was injected to a broiler's duodenum by technology of in situ ligated intestinal loops and a perfusion group without Fe sources added to the media was designed to exclude the effect of endogenous Fe.Being incubated for 30 min,duodenal midpieces sections were collected for analyses by μ-XRF and μ-XANES techniques.It was found that Fe concentration for ferrous Fe sources [FeSO_4 and Fe-Gly (Ⅱ)] was significantly higher than that for ferric Fe sources [FeCl_3 and Fe-Gly (Ⅲ)] in the duodenal wall,moreover,Fe-Gly (Ⅱ) group samples had the largest amount of Fe.μ-XANES spectra of Fe for the four sources were basically the same in the duodenal wall,which indicated that despite the ferric iron supplied to duodenum,ferrous iron could also be absorbed into the duodenal wall.     

Dynamic Changes of Endothelium Derived Factors and Cyclic Nucleotides in Ascites Broilers and Control of L-arginine

A flock of AA breed chickens were reared in peterstme brood-vait chamber using high energypelleted feed, at 14 days of age, 400 birds were separated into 3 groups randomly as follows: 100 birds wereexposed to normal ambient temperature (20℃) as control group, 150 birds were exposed to low ambient tem-perature (11℃) in order to induce ascites as treatment Ⅰ group, another 100 birds were also exposed to lowambient temperature (11℃) and fed the diets containing 1% L-arginine for ascitic prophylactic treatment astreatment Ⅱ group. The blood samples were collected on 3, 4, 5, 6, 7 wk, respectively, to measure the con-tents of plasma endothelin (ET-1), angiotensin Ⅱ (Ang Ⅱ ) and cyclic adenosine monophosphate (cAMP) andcyclic guanosine monophosphate (cGMP). The results indicated that the contents of cAMP, cGMP, Ang Ⅱand the ratio of cAMP/cGMP in treatment Ⅰ and ascitic broilers were higher than that of correspondent con-trol group(P＜0.01, P＜0.05), ET-1 of preascitic broilers were higher than that of control group(P＜0.05),while there were insignificant differences with later ascitic broilers, the contents of cAMP and cGMP in treat-ment Ⅱ were higher than treatment Ⅰ and control group(P＜0.01, P＜0.05), whereas, the ratio of cAMP/cGMP and the contents of Ang Ⅱ were gradually decreased than that of control group(P＜0.05), the contentsof ET-1 were not changed. By further analysis, the increased plasma Ang Ⅱ at low ambient temperature condi-tion in broilers made endothelium cell secretion of increased ET-1, cAMP, cGMP and decreased NO. So lowtemperature accelarated ascites syndrome in broilers. Supplemented L-arginine can decrease ET-1, cAMP andcAMP/cGMP. It is concluded that cAMP mediated pulmonary hypertension syndrome in broilers.     

Effects of Multi-enzyme Preparations on Growth Performance,Apparent Total Tract Digestibility and In Vitro Digestibility for Growing Pigs

The aim of this study was to investigate the effects of enzyme supplementations on performance of growing pigs, apparent total tract digestibility （ATTD） and in vitro digestibility （IVD） of nutrients. 224 growing pigs weighing 30-4-1.2 kg were allocated to fed basal diets supplemented with 0, 0.1, 0.15 or 0.2 g/kg enzyme preparations in growth trail. Those four diets were used for in vio＇o digestibility study. Pigs fed enzyme-supplemented diets improved average daily gain and decreased ratio of feed/gain （P〈0.05）. Enzyme supplementations increased ATTD of dry matter, energy, crude protein, neutral detergent fiber, acid detergent fibre and hemicellulose （P〈0.05）. Supplementation with enzymes improved reducing sugar production and the IVD of dry matter, crude protein, neutral detergent fiber, acid detergent fibre, total arabinoxylans, galacturonic acid, hemicellulose and cellulose. 0.015% enzyme supplementation in diets seemed to be sufficient to achieve maximum growth performance, nutrients digestibilities and reducing sugar production. Collectively, these results suggested that the supplementation of enzymes in diet increased the digestibilities of nutrients through the promotion of NSP degradation, thereby enhancing growth performance of growing pigs.     

Effect of Graded Levels of Fiber from Alfalfa Meal on Nutrient Digestibility and Flow of Fattening Pigs

The fiber level and composition have an important effect on nutrient digestibility of swine diets. Little information is known about the effects of fiber level and composition from alfalfa meal on nutrient digestibility of fattening pigs fed a corn-soybean meal-based diet. The objective of this experiment was to determine the effects of alfalfa fiber on the growth performance, intestinal nutrient flow and apparent total tract digestibility（ATTD） of nutrients in fattening pigs. 24 barrows（Duroc×（Large White×Landrace）, body weight=（60.6±0.7） kg） were randomly allotted to 4 treatments with 6 replicates of 1 pig per replicate. The pigs were provided a control diet or a diet containing 5, 10 or 20% of alfalfa meal during a 14-d experiment period. Average daily gain（ADG） and the ATTD of dry matter（DM）, organic matter（OM）, crude protein（CP）, neutral detergent fiber（NDF）, acid detergent fiber（ADF） and gross energy（GE） reduced linearly as the level of alfalfa meal in the diet increased（P〈0.01）. The total tract flow of DM, OM, CP, NDF, ADF, and GE increased with the increase in dietary alfalfa（linear, P〈0.05）. Growth performance and nutrient digestion were not affected by inclusion of 5% alfalfa meal in the diet（P〉0.05）. A multiple linear regression analysis, taking into account both soluble and insoluble fiber intake, explained approximately 70% of the variation in the ATTD of DM, OM, NDF, and GE（P〈0.01）. In conclusion, alfalfa meal should be limited to less than 5% of the diet in fattening pigs to maximize growth performance and nutrient digestion. Soluble and insoluble fiber from alfalfa meal has the differential roles in nutrient digestion, which may help explain the main variation observed in nutrient digestibility. These findings suggest that knowledge of specific fiber components is necessary to accurately predict the effects of dietary fiber on nutrient digestibility.     

Effects of Dietary Supplementation of Zinc-Methionine on Growth Performance and Serum Parameters of Jirong Rabbits

A 45-day growth trial was conducted to investigate the effects of 4 concentrations （0, 40, 80, 120 mg·kg^-1 Zinc- Methionine （Zn-Met） supplementation on growth and serum biochemical indexes of Jirong rabbits （60-day-old）. A total of 72 Jirong rabbits were randomly divided into 4 groups, 3 replicates with 6 rabbits each. The Met value in the basal diet was 0.60%. ADGs of group Ⅱ, Ⅲ and Ⅳ were significantly different than that of control, increased by 3.16%, 7.53%, 8.14% during 0-15 days and 7.58%, 15.60%, 15.71% during 16-30 days and 8.27%, 12.43%, 11.44% during 31-45 days （P〈0.05）, but it was not significantly different in ADG among group Ⅱ, Ⅲ and Ⅳ （P〉0.05）. The fur area and the density of hair of groups Ⅱ, Ⅲ and Ⅳ were not significantly different than that of control （P〉0.05）. The content of serum zinc, AKP, ALB for groups Ⅱ, Ⅲ and Ⅳ were significantly different than that of control （P〈0.05）. The serum TP and SUN in group Ⅱ, Ⅲ and IV were not significantly different than that of control （P〉0.05）. The results show that dietary supplementation of Zn-Met is much more efficient than dietary without Zn-Met for 60-day-old Jirong rabbits.     

Impacts of High Fiber Diet on Digestion and Absorption of Minerals in Growing Pigs

The study was conducted to investigate the effects of feeding high-fiber diet （HFD） on apparent total tract digestibility （ATTD） and absorption of minerals in growing pigs. Sixteen barrows averaging 16.39 kg were randomly assigned to one of four diets after metabolic crate assignment with individual pig serving as experimental unit. Diets include： a corn-soybean meal based low-fiber diet （LFD）, as the control （CON） and 3 HFD （D1, D2 and D3）, each containing 5% sugar beet pulps and a 1：2, 1：1 and 2：1 oats to barley ratios, respectively, replacing 47% of the corn in the diet. Diets were formulated to meet nutrient requirements, however, the fiber content of the LFD was substantially lower than the average of the HFD （8.38% vs. 22.40%）. Feed allowance was limited to 10% of average body weight and fed twice/d. The study period was divided into 10 d of adjustment and 5 d of feces collection. Data collected were analyzed using SAS, GLIMMIX procedure where animals were considered random effects, and minerals were fixed. Results of the study show that digestibility of Ca in pigs fed HFD was lower （P 〈 0.05） than in pigs fed LFD. On the other hand, the apparent digestibility of P, K, Na, S and Zn in pigs fed D2 and D3 were higher （P 〈 0.05） than in pigs fed CON diet. It was also observed that digestibility of Ca, P, K, Na, S and Zn in pigs fed D1 were lower （P 〈 0.05） than in CON, D2 or D3 fed pigs. Therefore, it was concluded that while feeding HFD reduced availability of Ca, the availability of P, K, Na and S to pigs improved as the oat to barley ratio in the diet increased.     

Effect of Different Oligosaccharides on Immunity, and Cecal Microflora in Broilers

One hundred and forty-four Avin broilers (1 d old) were randomly divided into six treatments, with three replicates of eight birds each to investigate the effect of different oligosaccharides on index of immune organ, cecal weight and microflora in broilers. The control group (Group Ⅰ) was fed with corn-soybean meal as basal diet, and the trial groups (group Ⅱ, Ⅲ, Ⅳ, Ⅴ and Ⅵ ) were fed with basal diet plus 0.1% manoligosaccharides (MOS), 0.3% soybean-oligosaccharides (SBOS), 0.3% fructooligosaccharides (FOS), 0.3% α -glucooligosaccharides(α -GOS) and 0.03% chlortetracycline (CTC), respectively. The results showed that oligosaccharides supplementation significantly (P＜0.05) increased bifidobacteria concentration ofyoung broilers and did not affect on bifidobacteria or escherichia coli concentration of the birds ( P ＞0.05). Cecal weights of 21 d old broilers fed with FOS and α -GOS were significantly (P ＜0.05) increased, higher than those with MOS and SBOS, but addition of oligosaccharides had no effect on the birds. The effect of oligosaccharides on the cecal length was the same as on the cecal weights. Oligosaccharides supplement did not affect on indexes of immune organs.     

Consuming fermented distillers' dried grains with solubles(DDGS)feed reveals a shift in the faecal microbiota of growing and fattening pigs using 454 pyrosequencing

The objective of this study was to investigate pig fed by Bacillus coagulans-fermented distillers' dried grains with solubles(DDGS)on the faecal microbial composition and diversity using 454 pyrosequencing. Healthy crossbred(Duroc×Yorkshire×Landrace)growing and fattening pigs(n=48),with an average initial body weight of 65 kg,were divided into two groups(24 replicates per group; four pens per group; six pigs per pen),and given either DDGS feed as the control,or B. coagulans-fermented DDGS feed as the treatment. Faecal samples were collected on day 0,7,14,21,and 28. DNA was extracted,and the V3–V6 region of the 16S rRNA gene was amplified. The fermented DDGS feed affected the relative abundance of bacteria populations at the phylum,genus,and species levels. At the genus level,the consumption of fermented DDGS feed led to higher relative abundances of faecal Prevotella,Lactobacillus,Clostridium,Bifidobacterium,Roseburia,and Bacillus,and lower relative abundances of faecal Escherichia,Ruminococcus,Dialister,unclassified Lachnospiraceae,unclassified Ruminococcaceae,and unclassified Enterobacteriaceae than in the control. At the species level,the consumption of fermented DDGS feed led to higher relative abundances of faecal Prevotella sp.,Lactobacillus johnsonii,Lactobacillus fermentum,Lactobacillus mucosae,Lactobacillus reuteri,Clostridium butyricum,Bifidobacterium sp.,and Roseburia sp.,and lower relative abundances of faecal Prevotella copri,Escherichia coli,Ruminococcus gnavus,Ruminococcus flavefaciens,and Dialister sp. than in the control. Principal coordinates analysis indicated a distinct separation in the faecal microbial communities of pigs that were fed the fermented and unfermented DDGS feed. Fermented DDGS feed significantly increased the average daily gain(ADG)of pigs,and significantly decreased the average daily feed intake(ADFI)of feed and feed/gain(F/G). Thus,our results demonstrate a beneficial shift in the faecal microbiota of pigs consuming fermented DDGS feed,with potential applications in livestock production.     

Effects of Maternal Dietary Energy Restriction on Fat Deposition of Offspring

The study was carried out to investigate the effects of maternal dietary energy restriction on growth performance, serum indices and fat deposition of offspring. A total of 400 female Arbor Acres （AA） broiler breeders were studied. These female birds involved three experimental treatments and a control group with normal dietary energy diets （ND, 11.7 MJ of ME. kgt during the laying）. In treatments 2, 3 and 4, the energies of diets were 20%, 30% and 50% （LD20, LD30 and LD50） lower than those of the control, respectively. The study commenced at the beginning of the laying period when the total egg production reached 5% of the flock. All the broiler offspring were fed the same diets. The results showed that in low energy diets, offspring showed decreased 1-day-old weight, but 49-day-old weight was higher in LD20 diet （P〈0.05）. For offspring during days 1-49, the average daily gain （ADG） in LD20 group and the feed conversion ratio in LD50 group were improved as compared with those of the control （P〈0.05）. Compared with the control, abdominal fat percentage increased in 49-day-old offspring from LD30 diet （P〈0.05）; the fat content of breast muscle in offspring increased in broilers fed low energy diets （P〈0.05）. In 28-day-old offspring from breeders given LD20 and LD50 diets, liver fat percentages were higher compared with ND （P〈0.05）. The subcutaneous fat thickness in 28-day-old offspring from LD50 group and 49-day-old offspring from LD30 group was higher （P〈0.05）. On day 49, the serum cholesterol （CHO） of offspring from breeders fed LD20 diet and serum high-density lipoprotein （HDL） of offspring from breeders fed LD50 diet reduced compared with those of the control （P〈0.05）. In addition, a higher triiodothyronine （T3） content in serum was found in offspring from broiler breeders given LD20 and LD30 diets （P〈0.05）. Serum thyroxine （T4） in offspring significantly decreased with the decrease of diet energy （P〈0.05）. In conclusion, to a certain extent, dietary energy restriction in breeders could improve growth performance and promote lipid metabolism of offspring.