Hepatic Lipogenesis Associated with Biochemical Changes in Overfed Landaise Geese and China Xupu Geese

This experiment studied hepatic lipogenesis associated with biochemical changes in overfed Landaise Geese and China Xupu geese. Twenty healthy male Landaise geese and 20 healthy male Xupu geese, hatched on the same day under the same feeding conditions, were selected as experimental animals. The animals were divided into two groups and each breed served as an experimental group. Per goose of per experimental group served for a repeat. Brown rice was selected as test diet. After overfeeding for 21 d and then slaughtering, the biochemical changes of hepatic lipogenesis in the genetic susceptibility to fatty liver were evaluated. These results showed that （1） the weight of fatty liver of the two breeds of geese were 801 and 375 g （P〈0.05）, respectively. There were no differences on the abdominal fat pat, filet total and filet pectoralis major in the two breeds experimental of the geese group （P〈0.05） and no difference on body and filet skin plus subcutaneous adipose tissue （P〉0.05） was found; （2） in these two breeds of geese, there were no differences on very-lowdensity lipoprotein （VLDL）, cholesteryl esters （CE） （P〈0.05）, free cholesterol （FC）, triglycerides （TG）, phospholipids （PL） and protein （P 〈 0.05）; （3） there were no differences on activities of malic enzyme （ME）, glucose-6-phosphatedehydrogenase （G6PDH）, acetyl-CoA-carboxylas （ACX）, fatty acid synthase （FAS）, and mRNA level of ME in the two experimental breeds of geese groups （P 〈0.05）; （4） test in Landaise geese group showed that there was no significant correlation with the specific enzymatic activities, while in Xupu geese group, the liver weight was negatively correlated to the specific activity of ACX and positively to that of ME; （5） in these overfed geese, ME activity appeared to be a major factor involved in the genetic susceptibility to hepatic steatosis and it determined the hepatic lipogenesis capacity.     

Regulatory Expression of Peroxisome Proliferator Activated Receptors Genes During Fatty Liver Formation in Geese

In order to investigate the expression pattern of peroxisome proliferator activated receptor （PPAR） genes before and after overfeeding, and estimate the effect of expressed PPAR levels on weights of fatty liver and abdominal fat in geese, the RT-PCR products of PPAR genes in heart, liver, spleen, lung, kidney, stomach, small intestine, brain, breast muscle, leg muscle, and abdominal fat were determined before and after overfeeding. RT-PCR was used to determine the expression levels of PPAR genes. Quantity one software was used to analyze absorbency, and the expression level of GAPDH gene was used as contrast. Expression levels of PPAR-α were relatively high in most of detected tissues but undetectable in abdominal fat tissue before overfeeding, and the level was evidently increased in lung, appeared in abdominal fat tissue, and reduced in the other tissues after overfeeding. Expressed PPAR-γ levels were relatively high in liver, spleen, lung, small intestine, and abdominal fat, and relatively low in the other tissues before overfeeding. Expressed PPAR-γ levels were enhanced in liver, spleen, lung, stomach, and kidney but decreased in abdominal fat and without obvious changes in the other tissues. Expression patterns of PPAR genes show tissue-specific manner. In addition, expression patterns of PPAR-α are different from PPAR-γ after overfeeding. It might suggest that different functions of PPAR subtypes are responsive to overfeeding.     

Effective Application of Nutritional Practices in Preventing Dairy Cow Fatty Liver

Fatty liver in dairy cows, which is associated with decreased metabolic function of the liver, develops during times of elevated non-esterified fatty acid （NEFA） concentrations in the blood when the hepatic uptake of lipids exceeds the oxidation and secretion of lipids by the liver and then it will cause hepatic accumulation of triglyceride （TG）. The condition is often related to decreased health status, well-being, productivity, and reproductive performance of cows. Prevention of fatty liver in the transition period is always better than any treatments. The nutritional preventative strategies mainly focus either on decreasing the supply of NEFA to liver, and it aims to improve liver function or optimize the capacity then to dispose of NEFA by exporting them as triglycerides in lipoproteins （VLDL）. Good dry cow nutritional programs, combined with excellent feeding management to achieve high levels of dry matter intake throughout the transition period should be the first priority for management. Several different compounds can promote these metabolic actions. The addition of glucose precursors such as glycerol, propyelene glycol, or propionate salts to the feed in the transition diet can modify metabolism in a manner to decrease fatty acid mobilization from adipose tissue and reduce the likelihood of liver TG accumulation. Supplying some other specific nutrients to dairy cows during the transition period may increase rates of NEFA disposal, with resulting effects on performance, though the hepatic capacities for export as triglycerides within VLDL are relatively limited in ruminants. Further studies examining nutritional and management strategies are required to develop new preventive or treatment options that are more practical to reduce the occurrence of fatty liver and its adverse metabolic effects.     

Physiological traits of rice seedlings in response to inorganic arsenic

The aim of our study was to better understand the different responses of rice seedling to different species of inorganic arsenic As203 （As（Ill）） and Na2HAsO4 （As（V））. Our results indicate that the biomass of rice seedling decreased as arsenic concentration increased, with the decrease being more significant at higher arsenic concentrations. In addition, the analysis of superoxide dimutase （SOD）, peroxidase （POD）, and catalase （CAT） in rice roots and leaves showed that the activity of these three enzymes significantly decreased in rice tissues, especially in rice roots, as arsenic concentration was increased,. Further, the uptake and utilization efficiencies of N, P, and K were found to decrease as arsenic concentration was increased. However, the uptake and utilization efficiencies of P and K were mainly affected by As（IlI）, whereas those of N were mainly affected by As（V）. Inductively coupled plasma-mass spectrometry （ICP-MS） was used to assay arsenic accumulation in rice tissues; the results indicate that the arsenic content in rice tissues was enhanced when arsenic concentration was increased, especially in rice roots after arsenic treatment.     

盐胁迫对水稻幼苗类囊体膜脂肪酸组分的影响(英文)

[Objective] The aim of the study is to understand the changes of fatty acid composition of rice thylakoid membrane under salt stress.[Method] Under salt stress of different concentrations of NaCl,rice seedlings of Pokkali and Peta with six leaves and one central leaf were used as experimental materials to extract the fatty acid from their thylakoid membranes,and gas chromatograph(1890)was used to analyze fatty acid composition.[Result] Fatty acid component 14∶0,18∶0,16∶1(3t),18∶1 in both the two experimental materials showed little variations in the first four days of salt stress,whereafter they increased slightly;while the fatty acid component 16∶0 and level of saturation of fatty acid(LSFA)showed the similar variation trend in the first four days of treatment compared to those of the fatty acid components mentioned above,whereafter they rose in Pokkali and presented an opposite variation trend in Peta;fatty acid component 18∶3 and level of unsaturation of fatty acid(LUFA)reduced all the time under stress condition,and the reducing amplitude in 100 mmol/L NaCl treatment group was smaller than that of 100 mmol/L NaCl treatment group,and in Pokkali was smaller than that in Peta under specific conditions.Meanwhile,level of saturation of fatty acid in both experimental materials increased,and the rising amplitude in Peta was smaller than that of Pokkali.[Conclusion] With regard to LUFA,Pokkali is endowed with more salt tolerance than Peta.     

Effects of Salt Stress on Fatty Acid Composition of Thylakoid Membrane of Two Rice Cultivars Differing in Salt Tolerance

[Objective] The aim of the study is to understand the changes of fatty acid composition of rice thylakoid membrane under salt stress.[Method] Under salt stress of different concentrations of NaCl,rice seedlings of Pokkali and Peta with six leaves and one central leaf were used as experimental materials to extract the fatty acid from their thylakoid membranes,and gas chromatograph(1890)was used to analyze fatty acid composition.[Result] Fatty acid component 14∶0,18∶0,16∶1(3t),18∶1 in both the two experimental materials showed little variations in the first four days of salt stress,whereafter they increased slightly;while the fatty acid component 16∶0 and level of saturation of fatty acid(LSFA)showed the similar variation trend in the first four days of treatment compared to those of the fatty acid components mentioned above,whereafter they rose in Pokkali and presented an opposite variation trend in Peta;fatty acid component 18∶3 and level of unsaturation of fatty acid(LUFA)reduced all the time under stress condition,and the reducing amplitude in 100 mmol/L NaCl treatment group was smaller than that of 100 mmol/L NaCl treatment group,and in Pokkali was smaller than that in Peta under specific conditions.Meanwhile,level of saturation of fatty acid in both experimental materials increased,and the rising amplitude in Peta was smaller than that of Pokkali.[Conclusion] With regard to LUFA,Pokkali is endowed with more salt tolerance than Peta.     

盐胁迫对水稻幼苗类囊体膜脂肪酸组分的影响(英文)

[Objective] The aim of the study is to understand the changes of fatty acid composition of rice thylakoid membrane under salt stress.[Method] Under salt stress of different concentrations of NaCl,rice seedlings of Pokkali and Peta with six leaves and one central leaf were used as experimental materials to extract the fatty acid from their thylakoid membranes,and gas chromatograph(1890)was used to analyze fatty acid composition.[Result] Fatty acid component 14∶0,18∶0,16∶1(3t),18∶1 in both the two experimental materials showed little variations in the first four days of salt stress,whereafter they increased slightly;while the fatty acid component 16∶0 and level of saturation of fatty acid(LSFA)showed the similar variation trend in the first four days of treatment compared to those of the fatty acid components mentioned above,whereafter they rose in Pokkali and presented an opposite variation trend in Peta;fatty acid component 18∶3 and level of unsaturation of fatty acid(LUFA)reduced all the time under stress condition,and the reducing amplitude in 100 mmol/L NaCl treatment group was smaller than that of 100 mmol/L NaCl treatment group,and in Pokkali was smaller than that in Peta under specific conditions.Meanwhile,level of saturation of fatty acid in both experimental materials increased,and the rising amplitude in Peta was smaller than that of Pokkali.[Conclusion] With regard to LUFA,Pokkali is endowed with more salt tolerance than Peta.     

Effects of Panicle Nitrogen Fertilization on Non-Structural Carbohydrate and Grain Filling in Indica Rice

Grain filling, a crucial stage of grain yield formation in rice, is usually affected by the panicle nitrogen （N） fertilization. Field and pot culture experiments were conducted to explore the underlying mechanisms of N effect. Two rice cultivars with high lodging resistance were grown in the field and pot. Four panicle N fertilization treatments were conducted in 2006 and repeated in 2007. The result showed that medium level of panicle N fertilization treatment （NM） enhanced the accumulation and translocation of non-structural carbohydrate （NSC） in the stem and sheath. Compared with non-nitrogen treatment （NO）, NM promoted the translocation of labeled ^13C from stem and sheath to grain. But, low level of panicle N fertilization treatment （NL） and high level of panicle N fertilization treatment （NH） showed the negative effect. The endosperm cell, grain length, and grain width of NM increased more quickly than that of NO from 4 to 10 d after anthesis. During the early period of grain filling, sucrose-phosphate synthase （EC 2.4.1.14, SPS） activity were significantly higher for the NM treatment than those of the NL and NH treatments. Sucrose synthase （EC 2.4.1.13, SuSase） activity in the grains was substantially enhanced by NM, with the duration of higher activity being longer than those of the other treatments. At maturing stage, NM significantly increased the filled grain number, the seed-setting rate, and the grain weight compared with NL and NH. The results suggest that NM have a positive effect on the activities of enzymes of physiological importance, thereby increasing the grain size and promoting grain filling.     

Effect of Wheat Based Diet Supplemented with Xylanase on Blood Sugar and Total Protein in Serum of Geese

[Objective] The effects of wheat based diet supplemented with xylanase on blood sugar and total protein in serum of geese were studied. [Method] By using the randomized design of single factor,the 1-day-old healthy goslings were divided into 6 groups and fed with corn based diet,wheat based diet and wheat based diet supplemented with xylanase at different concentrations respectively,the contents of blood sugar and total protein in serum were determined. [Result] The wheat based diet supplemented with xylanase could increase the blood sugar and total protein in serum of geese and wheat based diet supplemented with 0.2% xylanase generated the best effect,which was higher than those of corn based diet group. As for the concentration of protein in serum,wheat based diet supplemented with 0.2% xylanase was significantly different from corn based diet and wheat based diet. [Conclusion] The wheat based diet supplemented with xylanase could enhance geese production.     

小麦饲粮中添加木聚糖酶对肉鹅血糖和血清总蛋白水平的影响(英文)

[Objective] The effects of wheat based diet supplemented with xylanase on blood sugar and total protein in serum of geese were studied. [Method] By using the randomized design of single factor,the 1-day-old healthy goslings were divided into 6 groups and fed with corn based diet,wheat based diet and wheat based diet supplemented with xylanase at different concentrations respectively,the contents of blood sugar and total protein in serum were determined. [Result] The wheat based diet supplemented with xylanase could increase the blood sugar and total protein in serum of geese and wheat based diet supplemented with 0.2% xylanase generated the best effect,which was higher than those of corn based diet group. As for the concentration of protein in serum,wheat based diet supplemented with 0.2% xylanase was significantly different from corn based diet and wheat based diet. [Conclusion] The wheat based diet supplemented with xylanase could enhance geese production.     

Carbon and nitrogen allocations in corn grown in Central and Northeast China: different responses to fertilization treatments

In order to reveal the impact of various fertilization strategies on carbon(C) and nitrogen(N) accumulation and allocation in corn(Zea mays L.), corn was grown in the fields where continuous fertilization management had been lasted about 18 years at two sites located in Central and Northeast China(Zhengzhou and Gongzhuling), and biomass C and N contents in different organs of corn at harvest were analyzed. The fertilization treatments included non-fertilizer(control), chemical fertilizers of either nitrogen(N), or nitrogen and phosphorus(NP), or phosphorus and potassium(PK), or nitrogen, phosphorus and potassium(NPK), NPK plus manure(NPKM), 150% of the NPKM(1.5NPKM), and NPK plus straw(NPKS). The results showed that accumulated C in aboveground ranged from 2 550–5 630 kg ha–1 in the control treatment to 9 300–9 610 kg ha–1 in the NPKM treatment, of which 57–67% and 43–50% were allocated in the non-grain organs, respectively. Accumulated N in aboveground ranged from 44.8–55.2 kg ha–1 in the control treatment to 211–222 kg ha–1 in the NPKM treatment, of which 35–48% and 33–44% were allocated in the non-grain parts, respectively. C allocated to stem and leaf for the PK treatment was 65 and 49% higher than that for the NPKM treatment at the both sites, respectively, while N allocated to the organs for the PK treatment was 18 and 6% higher than that for the NPKM treatment, respectively. This study demonstrated that responses of C and N allocation in corn to fertilization strategies were different, and C allocation was more sensitive to fertilization treatments than N allocation in the area.     

Effects of Immunization Against Inhibin on Egg-Laying Performance in Magang and Landaise Geese

This study aimed to improve egg-laying performance in incubating Magang geese of Guangdong origin and Landaise geese of French origin. In experiment 1, 50 adults, egg-laying Magang geese were inoculated intramuscularly （i.m.） on days 0, 22, and 45 with 1 mL of immunogen containing 1 mg of recombinant chicken inhibin fusion protein. Immunization significantly increased blood antibody titers against inhibin fusion protein, but did not affect the egg-laying performance within 10 days after the first inoculation. From day 15, the egg-laying rate in inhibin-immunized group increased and was significantly higher than the values of control geese from day 40 to 55. However, the reverse was true from day 55 to 75 when more immunized geese developed incubation. In the entire 120 days of the experiment, the immunized geese laid 17.3 eggs in contrast to 16.4 eggs laid by the control geese. From day 30 till the end of the experiment, weight of eggs in the control geese was significantly greater than that in inhibin-immunized birds. In experiment 2, 40 Landaise geese were immunized against inhibin, as described in experiment 1. These geese laid 9.0 eggs on average in contrast to 7.3 eggs laid by nonimmunized control geese over 90 days of egg laying. The above results demonstrated that immunization against recombinant chicken inhibin fusion protein improved egg-laying performance in geese, and the increment was higher in nonincubating geese.     

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.     

Susceptibility of Ostrinia furnacalis to Bacillus thuringiensis and Bt Corn Under Long-Term Laboratory Selection

The susceptibility of the Asian corn borer, Ostriniafurnacalis to Bacillus thuringiensis (Bt) formulation and Bt corn was evaluated using insect bioassays for 6 years. Four strains of O. furnacalis were developed by laboratory selection from the laboratory strain reared on a non-agar semi-artificial diet. The RR-1 strain was exposed to a commercial formulation of B. thuringiensis subsp, kurstaki (Btk) incorporated into the artificial diet, the RR-2 strain was exposed to Bt corn (MON810)tissue incorporated into the diet, and the SS-1 and SS-2 strains were reared on the standard diet with or without non-Bt corn tissues material. Decreasing susceptibility of O. furnacalis to Bt and to Bt corn were found in each selected strain although the EDs0 and larval weight fluctuated from generation to generation. The resistance of Bt-exposed strain (RR-1)to Btk increased 48-fold by generation 39; the Bt corn-exposed strain (RR-2) increased its resistance 37-fold to Btk by generation 24. No larvae of SS- 1 survived when they were exposed to the leaves of Bt corn, Bt 11 and MON810. However,2-54% of the RR-1 (generation 46) and RR-2 (generation 20) larvae survived a 3 day-exposure to the leaves of Btl 1 and MON810. The survival of both selected strains on Bt corn silk increased by 10-69%, and the larval weights after many generations selection were increased by 15-22% compared with the unselected susceptible strain. The young larvae were much more susceptible to Bt than older larvae. The highest mortality occurred when the larvae were exposed to Bt at the neonate stage. All of the results suggested that ACB could not only develop resistance to Bt preparation but also to Bt corn. Bt had significant effects on the growth and development of Asian corn borer than on the larval mortality. In order to maintain the long-term effectiveness of Bt pesticide and Bt corn, the resistance management should pay much attention to the larvae that may have opportunities to grow and developed on non-Bt corn or alternate hosts before they attack the Bt corn plants and the survival of larvae after Bt application.     

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.     

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.     

The Difference in Growth and Four Microelement Concentrations Between Two Rice Genotypes Differing in Grain Cadmium-Accumulating Capacity

A pot experiment was conducted with two rice genotypes having different Cd concentrations in their grains to study the effect of soil Cd level on biomass, Cd and Fe, Zn, Cr and Pb accumulation in different plant parts. Cd was added into soil to form 4 levels, i.e.,0, 0.5, 2.5 and 12.5 mg kg^-1, respectively. The results showed that the Cd-induced reduction in biomass accumulation varied in both genotypes and growth stages. The Cd-induced reduction in biomass became less with the progress of growth, and Xiushui63, a genotype with relatively higher grain Cd concentration, was more severely inhibited than Xiushui217,a relatively lower Cd concentration. Both Cd concentration and accumulation in the various plant parts increased substantially with the increase of Cd levels. The difference between two genotypes in Cd concentration and accumulation became more pronounced with increased Cd level as well as prolonged duration of exposure. Xuishui63 had much greater Cd accumulation than Xiushui217, in particular at late growth stage. Xuishui63 had a remarkably higher Cd translocation of roots to shoots than Xiushui217 in all Cd levels.The effect of Cd addition on four microelement concentrations in straw and milled riceal so varied in genotypes and Cd levels. Without Cd addition, Xiushui63 was significantly lower than Xiushui217 in the concentrations of all four elements in straw, while the case was just opposite in milled rice. Zn, Fe and Pb concentrations decreased in milled rice with the increase of Cd level, although the reduction extent differed in two genotypes.The results indicated that Cd concentration in rice grain is primarily dependent on the shoot Cd concentration, which is in turn mainly determined by Cd translocation from roots to shoots.     

Lipase and Phospholipase in the Hydrolysis of Lipids in Wastewater from Swine Slaughterhouse and Subsequent Biological Treatment Study

Wastewaters from slaughterhouses are characterized by a high concentration of oils and greases that can cause problems in conventional treatments. The degradation of difficult pollutants in more easily degradable products can be mediated by enzymes. Enzymatic hydrolysis facilitates the biodegradation because it makes the organic material is made available as compounds of lower molecular weight, the lipids being made available in the form of free fatty acids. The application of enzymes as processing aids in wastewater treatment has some advantages, such as the specificity that allows control of the products, which leads to increased income generation for the non-toxic byproducts and moderate conditions of operation. The objective of this work was optimizing the conditions for lipids enzymatic hydrolysis present in swine slaughterhouse wastewaters using lipolytic enzymes and subsequent biological treatment study. Temperature, pH and enzyme concentration were the variables tested. The enzymes showed good activity and could therefore be used for the hydrolysis process proposed here. The optimized conditions to maximize the release of fatty acids were： temperature of 36 ℃, pH 8.5 and enzyme concentration of 1.1%, yielding fatty acids in the order of 31.50μmol/mL for lipase and 31.13 μmol/mL for phospholipase. All variables influenced the release of fatty acids. The maximum yield of biogas was 89.65 mL in the reactor added the sludge, raw wastewater and phospholipase in the conditions optimized the hydrolysis step, obtaining a chemical oxygen demand （COD） reduction of 90.01% in relation to the value of the COD of the raw wastewater.     

Combined effect of shading time and nitrogen level on grain filling and grain quality in japonica super rice

There is limited information about the combined effect of shading time and nitrogen(N) on grain filling and quality of rice. Therefore, two japonica super rice cultivars, Nanjing 44 and Ningjing 3, were used to study the effect of shading time and N level on the characteristics of rice panicle and grain filling as well as the corresponding yield and quality. At a low N level(150 kg N ha~(–1), 150 N), grain yield decreased(by 21.07–26.07%) under the treatment of 20 days of shading before heading(BH) compared with the no shading(NS) treatment. These decreases occurred because of shortened panicle length, decreased number of primary and secondary branches, as well as the grain number and weight per panicle. At 150 N, in the treatment of 20 days of shading after heading(AH), grain yield also decreased(by 9.46–10.60%) due to the lower grain weight per panicle. The interaction of shading and N level had a significant effect on the number of primary and secondary branches. A high level of N(300 kg N ha~(–1), 300 N) could offset the negative effect of shading on the number of secondary branches and grain weight per panicle, and consequently increased the grain yield in both shading treatments. In superior grains, compared with 150 N NS, the time to reach 99% of the grain weight(T_(99)) was shortened by 1.6 to 1.7 days, and the grain weight was decreased by 4.18–5.91% in 150 N BH. In 150 N AH, the grain weight was 13.39–13.92% lower than that in 150 N NS due to the slow mean and the maximum grain-filling rate(GR_(mean )and GR_(max)). In inferior grains, grain weight and GR_(mean) had a tendency of 150 N NS150 N BH150 N AH. Under shaded conditions, 300 N decreased the grain weight due to lower GR_(mean) both in superior and inferior grains. Compared with 150 N NS, the milling and appearance qualities as well as eating and cooking quality were all decreased in 150 N BH and 150 N AH. Shading with the high level of 300 N improved the milling quality and decreased the number of chalky rice kernels, but the eating and cooking quality was reduced with increased chalky area and overall chalkiness. Therefore, in the case of short term shading, appropriate N fertilizer could be used to improve the yield and milling quality of rice, but limited application of N fertilizer is recommended to achieve good eating and cooking quality of rice.     

Effects of Selenium on Lipid peroxidation and Oxidizing Ability of Rice Roots under Ferrous Stress

Water culture experiment was conducted to study the effects of selenium(Se)on glutathione peroxidase (GSH-Px) activity,reduced glutathione (GSH) concentration and the accumulation of malonaldehyde (MDA),the product of lipid peroxidation in rice seedling ,as well as the effect of se on oxidizing ability of roots under ferrous stress,Results showed that appropriate amount of se significantly increased GSH-Px activity in rice leaves,F=5.5^*,enhanced the amount of GSH and oxidizing ability of roots and reduced the concentration of MDA,F=4.9^*,Compared with Se0 Fe treatment,Se treatments increased the dry matter weitht of rice seedling from 10.06%to 10.43%,F=4.09^*.