The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory ...The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory study to evaluate the effect of a thatch layer on the dynamics of water-soluble P in undisturbed cores taken from a pasture. Cores with and without a thatch layer received a surface application of broiler litter (5 thm-2) and were incubated at 25 oC for 56 d. The result showed that on the soil surface the contents of water soluble-P (39 kghm-2) of the cores with the thatch layer was higher than that (20 kghm-2) of the cores without the thatch layer. Therefore on well-established pastures fertilized with broiler litter, the presence of a thatch layer might lead to high concentrations of water-soluble P on the soil surface.展开更多
为研究饲粮添加氧化油脂和金荞麦对肉鸡肉品质和空肠黏膜miRNA表达谱的影响,试验选用1日龄健康、体重相近的882肉仔鸡公鸡240只,随机分为3组,每组8个重复,每个重复10只鸡。Ctr、Ox、Fag组分别在基础日粮中添加新鲜油脂、氧化油脂、新鲜...为研究饲粮添加氧化油脂和金荞麦对肉鸡肉品质和空肠黏膜miRNA表达谱的影响,试验选用1日龄健康、体重相近的882肉仔鸡公鸡240只,随机分为3组,每组8个重复,每个重复10只鸡。Ctr、Ox、Fag组分别在基础日粮中添加新鲜油脂、氧化油脂、新鲜油脂+2%金荞麦。试验期为42 d。结果显示:氧化油脂可显著增加胸肌24 h pH和腿肌滴水损失(P<0.01),显著降低胸肌肉色a^(*)值(P<0.05);金荞麦可显著增加腿肌肉色L^(*)和a^(*)值(P<0.05);Ctr vs Ox,Ctr vs Fag,Ox vs Fag三个比较组的差异表达miRNAs分别为25、27、24个;这些差异表达miRNAs的靶基因显著富集在肌动蛋白细胞骨架、紧密链接、mTOR和TGF-β等信号通路;根据表达丰度和表达差异分析,共筛选了17个差异表达miRNAs,它们可作为氧化油脂和金荞麦调控肠道屏障功能的候选基因,进一步研究氧化油脂和金荞麦通过表观遗传学对肠道屏障功能的影响。综上所述,饲粮添加氧化油脂和2%金荞麦均可改变肉鸡肉品质,影响空肠黏膜miRNAs的表达谱。展开更多
The study aimed to investigate and compare the contents of carboxymethyllysine(CML)in two kinds of broilers during postmortem ageing and storage.The contents of CML in raw and boiled(100℃,30 min)broiler briskets and ...The study aimed to investigate and compare the contents of carboxymethyllysine(CML)in two kinds of broilers during postmortem ageing and storage.The contents of CML in raw and boiled(100℃,30 min)broiler briskets and legs which were from white feather broilers(n=8)and yellow feather broilers(n=8)with ageing and storage at 4℃for 0-168 h were determined.Postmortem ageing and storage had a significant(P<0.05)effect on the color and A;in both boiled broilers meat.In addition,with the ageing and storage time increasing,CML content in raw white feather broiler brisket meat had no significant(P>0.05)change,while that in boiled brisket meat significantly(P<0.05)increased during 0-6 h,then decreased during 6-24 h,finally increased again.CML content in leg meat increased significantly(P<0.05)with the ageing and storage time prolonging.But postmortem ageing and storage had no significant(P>0.05)effect on the CML contents in raw/boiled yellow feather broilers.Meanwhile,CML contents in white feather broilers were much higher than that in yellow feather broilers.Thus,white feather broilers can be selected as the research object to study the mechanism of ageing and storage on CML content in the postmortem broiler in the future.展开更多
A six-week experiment was conducted to investigate the effects of supplementing different enzyme cocktails in cornsoybean-byproduct diets on broiler chickens＇ growth performance and nutrient utilization. A total of 6...A six-week experiment was conducted to investigate the effects of supplementing different enzyme cocktails in cornsoybean-byproduct diets on broiler chickens＇ growth performance and nutrient utilization. A total of 630 one-day-old Arbor Acre broiler chicks were randomly allocated to 7 experimental groups with 6 replicates of 15 chicks. The group of chicks serving as the control group were fed a basal diet made of mainly corn and soybean meal, mixed with a little fish meal, rapeseed meal and wheat bran. The other six groups were fed the same basal diet supplemented with each a different enzyme complex at the dosage of 0.75 kg enzyme in 1 t basal diet. At the same time, a metabolic trial was carded out on 42 chicks at the 27 d age. The results showed that the average daily mass gain （ADG） of chicks in the starter phase, age 1 d to 21 d, was improved by all enzyme complex supplements except the cocktail made of 230 IU/g α-amylase, 5.6 klU/g β-glucanase, 5.3 kIU/g cellulase, 15.5 kIU/g protease and 37.5 kIU/g xylanase. The enzyme cocktail made of 1.6 klU/g α-amylase, 80 klU/g protease and 1.6 kIU/g xylanase worked out the most significant difference （P〈0.05）. Enzyme supplementation decreased the feed conversion ratio （FCR） by 2.78% to 3.98% （P〉0.05）, indicating better utilization of nutritients. In the grower phase at the age from 22 d to 42 d, the enzyme cocktail made of 4.0 kIU/g β-glucanase, 3.8 kIU/g cellulase, 17.8 kIU/g protease, 4.5 kIU/g xylanase and 44 IU/g α-glactase, and that made of 240 IU/g α-amylase, 1.4.6 kIU/g β-glucanase, 2.0 kIU/g cellulase, 5.7 klU/g protease, 400 IU/g xylanase, 20 IU/g α- glactase and 200 IU/g phytase imporved chicks＇ ADG and FCR significantly （P〈0.05）. These two cocktails also were shown to improve ADG and FCR in the entire period of broiler age from 1 d to 42 d. Exogenous digesting enzymes such as protease and amylase benefited the growth and nutrition utilization in young broilers in the starter phase but barely in the grower phase, indicating the underdeveloped intestine of young broilers cannot secrete sufficient digestive enzymes, making an exogenous supplement necessary. Application of an enzyme complex supplement to a maize-soybean diet for broiler chickens challenges attention to selecting suitable enzymes and their proper dosages according to basal diet composition and the age of the broilers.展开更多
480 healthy 1-day-old male yellow-feathered chickens were selected and assigned randomly into groups A and B,each having 6 pens with 40 birds per pen.The birds in group A were fed with wheatbased diet and group B with...480 healthy 1-day-old male yellow-feathered chickens were selected and assigned randomly into groups A and B,each having 6 pens with 40 birds per pen.The birds in group A were fed with wheatbased diet and group B with wheat-based diet supplemented with xylanase(1.2×l0~4 U/kg diet).On day 16,two birds per replication with average live weight were selected and sacrificed.Tissue samples of jejunum and ileum were collected to detect mRNA expression of cationic amino acid transporters using RT-PCR.The results showed that xylanase significantly increased the abundance of mRNA for rBAT and CAT4 in the intestines of broilers fed with wheat-based diets(P<0.05)and had a tendency to increase the mRNA expression of y^+LAT2 and CAT1 in jejunum(P>0.05),y^+LAT2,CAT1 and CAT4 in ileum(P>0.05).The treatment had no effect on the expression of rBAT mRNA in ileum(P>0.05).展开更多
The present experiment was performed with the objective of examining the effects of copper sources and levels on hydrogen peroxide(H_2O_2) generation by mitochondria from broiler hepatocytes. Treatments were applied t...The present experiment was performed with the objective of examining the effects of copper sources and levels on hydrogen peroxide(H_2O_2) generation by mitochondria from broiler hepatocytes. Treatments were applied to compare sources of copper(CuSO_4 versus Cu-Met) and 4 levels of dietary Cu (11,110,220 and 330 mg/kg).Day-old broilers(Cobb 500,Gallus domesticus,n=288) were randomly divided into 8 groups of 36 each and fed diets as follows:Controls(Cu 11 mg/kg) and high copper(Cu 110, 220,and 330 mg/kg),for 60 days under normal conditions.Sample collections were made at 12,36 and 60 days of age to investigate the changes in H_2O_2 generation by mitochondria from hepatocytes.Compared with those of the control diets,H_2O_2 generation by mitochondria in the high copper groups(110 to 330 mg/kg) of the two copper sources were increased(P<0.05 or P<0.01);At days 36 and 60,H_2O_2 generation by hepatic mitochondria from Cu-Met supplementation exceeded that from birds supplemented with CuSO_4 (P<0.05 or P<0.01).In addition,H_2O_2 generation by mitochondria from broilers fed with high dietary copper appeared to be associated with altered function of mitochondrial complexⅣ.The results indicated that dietary supplementation with copper induced oxidative stress damage in liver.At each level of copper supplementation,the organic Cu-Met led to more rapid H_2O_2 generation than did inorganic CuSO_4.The results also suggest that mitochondrial complexⅣmay be targeted under conditions of high dietary copper supplementation.展开更多
文摘The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory study to evaluate the effect of a thatch layer on the dynamics of water-soluble P in undisturbed cores taken from a pasture. Cores with and without a thatch layer received a surface application of broiler litter (5 thm-2) and were incubated at 25 oC for 56 d. The result showed that on the soil surface the contents of water soluble-P (39 kghm-2) of the cores with the thatch layer was higher than that (20 kghm-2) of the cores without the thatch layer. Therefore on well-established pastures fertilized with broiler litter, the presence of a thatch layer might lead to high concentrations of water-soluble P on the soil surface.
文摘为研究饲粮添加氧化油脂和金荞麦对肉鸡肉品质和空肠黏膜miRNA表达谱的影响,试验选用1日龄健康、体重相近的882肉仔鸡公鸡240只,随机分为3组,每组8个重复,每个重复10只鸡。Ctr、Ox、Fag组分别在基础日粮中添加新鲜油脂、氧化油脂、新鲜油脂+2%金荞麦。试验期为42 d。结果显示:氧化油脂可显著增加胸肌24 h pH和腿肌滴水损失(P<0.01),显著降低胸肌肉色a^(*)值(P<0.05);金荞麦可显著增加腿肌肉色L^(*)和a^(*)值(P<0.05);Ctr vs Ox,Ctr vs Fag,Ox vs Fag三个比较组的差异表达miRNAs分别为25、27、24个;这些差异表达miRNAs的靶基因显著富集在肌动蛋白细胞骨架、紧密链接、mTOR和TGF-β等信号通路;根据表达丰度和表达差异分析,共筛选了17个差异表达miRNAs,它们可作为氧化油脂和金荞麦调控肠道屏障功能的候选基因,进一步研究氧化油脂和金荞麦通过表观遗传学对肠道屏障功能的影响。综上所述,饲粮添加氧化油脂和2%金荞麦均可改变肉鸡肉品质,影响空肠黏膜miRNAs的表达谱。
基金supported by the China Agriculture Research System(CARS-41-Z)。
文摘The study aimed to investigate and compare the contents of carboxymethyllysine(CML)in two kinds of broilers during postmortem ageing and storage.The contents of CML in raw and boiled(100℃,30 min)broiler briskets and legs which were from white feather broilers(n=8)and yellow feather broilers(n=8)with ageing and storage at 4℃for 0-168 h were determined.Postmortem ageing and storage had a significant(P<0.05)effect on the color and A;in both boiled broilers meat.In addition,with the ageing and storage time increasing,CML content in raw white feather broiler brisket meat had no significant(P>0.05)change,while that in boiled brisket meat significantly(P<0.05)increased during 0-6 h,then decreased during 6-24 h,finally increased again.CML content in leg meat increased significantly(P<0.05)with the ageing and storage time prolonging.But postmortem ageing and storage had no significant(P>0.05)effect on the CML contents in raw/boiled yellow feather broilers.Meanwhile,CML contents in white feather broilers were much higher than that in yellow feather broilers.Thus,white feather broilers can be selected as the research object to study the mechanism of ageing and storage on CML content in the postmortem broiler in the future.
基金Singapore Kemin Industries Pte Ltd. under the Contract No.200103006
文摘A six-week experiment was conducted to investigate the effects of supplementing different enzyme cocktails in cornsoybean-byproduct diets on broiler chickens＇ growth performance and nutrient utilization. A total of 630 one-day-old Arbor Acre broiler chicks were randomly allocated to 7 experimental groups with 6 replicates of 15 chicks. The group of chicks serving as the control group were fed a basal diet made of mainly corn and soybean meal, mixed with a little fish meal, rapeseed meal and wheat bran. The other six groups were fed the same basal diet supplemented with each a different enzyme complex at the dosage of 0.75 kg enzyme in 1 t basal diet. At the same time, a metabolic trial was carded out on 42 chicks at the 27 d age. The results showed that the average daily mass gain （ADG） of chicks in the starter phase, age 1 d to 21 d, was improved by all enzyme complex supplements except the cocktail made of 230 IU/g α-amylase, 5.6 klU/g β-glucanase, 5.3 kIU/g cellulase, 15.5 kIU/g protease and 37.5 kIU/g xylanase. The enzyme cocktail made of 1.6 klU/g α-amylase, 80 klU/g protease and 1.6 kIU/g xylanase worked out the most significant difference （P〈0.05）. Enzyme supplementation decreased the feed conversion ratio （FCR） by 2.78% to 3.98% （P〉0.05）, indicating better utilization of nutritients. In the grower phase at the age from 22 d to 42 d, the enzyme cocktail made of 4.0 kIU/g β-glucanase, 3.8 kIU/g cellulase, 17.8 kIU/g protease, 4.5 kIU/g xylanase and 44 IU/g α-glactase, and that made of 240 IU/g α-amylase, 1.4.6 kIU/g β-glucanase, 2.0 kIU/g cellulase, 5.7 klU/g protease, 400 IU/g xylanase, 20 IU/g α- glactase and 200 IU/g phytase imporved chicks＇ ADG and FCR significantly （P〈0.05）. These two cocktails also were shown to improve ADG and FCR in the entire period of broiler age from 1 d to 42 d. Exogenous digesting enzymes such as protease and amylase benefited the growth and nutrition utilization in young broilers in the starter phase but barely in the grower phase, indicating the underdeveloped intestine of young broilers cannot secrete sufficient digestive enzymes, making an exogenous supplement necessary. Application of an enzyme complex supplement to a maize-soybean diet for broiler chickens challenges attention to selecting suitable enzymes and their proper dosages according to basal diet composition and the age of the broilers.
基金supported by National Key Basic Research Development Program 973 of China(No.2004CB117501)National Natural Science Foundation of China(No.30671519)Guangdong Province Scientific Technology Research Project(No.2005B20201016)
文摘480 healthy 1-day-old male yellow-feathered chickens were selected and assigned randomly into groups A and B,each having 6 pens with 40 birds per pen.The birds in group A were fed with wheatbased diet and group B with wheat-based diet supplemented with xylanase(1.2×l0~4 U/kg diet).On day 16,two birds per replication with average live weight were selected and sacrificed.Tissue samples of jejunum and ileum were collected to detect mRNA expression of cationic amino acid transporters using RT-PCR.The results showed that xylanase significantly increased the abundance of mRNA for rBAT and CAT4 in the intestines of broilers fed with wheat-based diets(P<0.05)and had a tendency to increase the mRNA expression of y^+LAT2 and CAT1 in jejunum(P>0.05),y^+LAT2,CAT1 and CAT4 in ileum(P>0.05).The treatment had no effect on the expression of rBAT mRNA in ileum(P>0.05).
基金supported by the National Natural Science Foundation of China(NSFC) awarded to Tang Zhao-xin(grant number:30671550)
文摘The present experiment was performed with the objective of examining the effects of copper sources and levels on hydrogen peroxide(H_2O_2) generation by mitochondria from broiler hepatocytes. Treatments were applied to compare sources of copper(CuSO_4 versus Cu-Met) and 4 levels of dietary Cu (11,110,220 and 330 mg/kg).Day-old broilers(Cobb 500,Gallus domesticus,n=288) were randomly divided into 8 groups of 36 each and fed diets as follows:Controls(Cu 11 mg/kg) and high copper(Cu 110, 220,and 330 mg/kg),for 60 days under normal conditions.Sample collections were made at 12,36 and 60 days of age to investigate the changes in H_2O_2 generation by mitochondria from hepatocytes.Compared with those of the control diets,H_2O_2 generation by mitochondria in the high copper groups(110 to 330 mg/kg) of the two copper sources were increased(P<0.05 or P<0.01);At days 36 and 60,H_2O_2 generation by hepatic mitochondria from Cu-Met supplementation exceeded that from birds supplemented with CuSO_4 (P<0.05 or P<0.01).In addition,H_2O_2 generation by mitochondria from broilers fed with high dietary copper appeared to be associated with altered function of mitochondrial complexⅣ.The results indicated that dietary supplementation with copper induced oxidative stress damage in liver.At each level of copper supplementation,the organic Cu-Met led to more rapid H_2O_2 generation than did inorganic CuSO_4.The results also suggest that mitochondrial complexⅣmay be targeted under conditions of high dietary copper supplementation.
