Responses of growth performance,antioxidant function,small intestinal morphology and mRNA expression of jejunal tight junction protein to dietary iron in yellow-feathered broilers

This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per cage.The dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)O.Compared with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(P<0.0001).Adding 640 and 1,280 mg Fe kg^(-1)significantly decreased ADG(P<0.0001)and average daily feed intake(ADFI)(P<0.0001)compared with supplementation of 20mg Fe kg^(-1).Malondialdehyde(MDA)concentration in plasma and duodenum increased linearly(P<0.0001),but MDA concentration in liver and jejunum increased linearly(P<0.05)or quadratically(P<0.05)with increased dietary Fe concentration.The villus height(VH)in duodenum and jejunum,and the ratio of villus height to crypt depth(V/C)in duodenum decreased linearly(P?0.05)as dietary Feincreased.As dietary Fe increased,the jejunal relative mRNA abundance of claudin-1 decreased linearly(P=0.001),but the jejunal relative mRNA abundance of zona occludens-1(ZO-1)and occludin decreased linearly(P?0.05)or quadratically(P?0.05).Compared with the supplementation of 20 mg Fe kg^(-1),the supplementation of640 mg Fe kg^(-1)or higher increased(P?0.05)MDA concentrations in plasma,duodenum,and jejunum,decreased VH in the duodenum and jejunum,and the addition of 1,280 mg Fe kg^(-1)reduced(P?0.05)the jejunal tight junction protein(claudin-1,ZO-1,occludin)mRNA abundance.In summary,640 mg of supplemental Fe kg^(-1)or greater was associated with decreased growth performance,increased oxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein.

Bioavailability and Immunity Response in Broiler Breeders on Organically Complexed Zinc Supplementation

Two hundred and sixty four broiler breeder hens of 32 weeks of age were distributed randomly in four dietary treatments. The dietary treatments were T0: Broiler breeder ration containing 40 ppm zinc (basal 29.8 ppm + 10.2 ppm inorganic zinc), T1: T0 + organic zinc (zinc methionine) @ 20 ppm, T2: T0 + organic zinc @ 40 ppm and T3: T0 + organic zinc @ 60 ppm. The experiment was continued from 32 to 48 weeks of age. At 48 weeks, the weight of lymphoid organs, zinc levels in organs and immunity response were determined. The faecal zinc level was determined at monthly interval. The weight lymphoid organs of different treatment groups (both organic and inorganic zinc fed groups) of the broiler breeders did not differ significantly (P > 0.05). The cellular immune response of breeder birds to PHA-P was significantly (P 0.05) higher in group T3 than the rest of treated groups. The antibody titre to SRBC differed among the treated groups. The zinc content of serum of broiler breeders of all the groups did not differ significantly (P > 0.05) in all the periods of study. Zinc content in liver and tibia of broiler breeders in different dietary treatments of zinc differed significantly (P 0.05) with higher levels were obtained on increasing zinc concentration in the diet. The zinc level in the spleen and kidney of the broiler breeders in different dietary treatments did not differ significantly (P > 0.05). The average zinc content in the faeces of broiler breeder during 35 to 43 week of age did not differ significantly (P > 0.05) among the treated groups. At 48 weeks of age, zinc content of the faeces of T3 was found to be significantly (P 0.05) higher than the rest of treated groups. Similarly, during the overall experimental period analysis, it was found that zinc levels in the faeces of T2 and T3 were significantly (P 0.05) higher than T1 and T0.

Molecular cloning and ontogenesis expression of fatty acid transport protein-1 in yellow-feathered broilers

Fatty acid transport protein-1 （FATP-1） is one of the important transporter proteins involved in fatty acid transmembrane transport and fat deposition. To study the relationship between FATP-1 mRNA expression and fat deposition, chicken （Gallus gallus） FATP-1 sequence was first cloned by rapid amplification of cDNA ends （RACE）. Tissue samples of chest muscle, leg muscle, subcutaneous fat, and abdominal fat were collected from six male and six female broilers each, at 22 days, 29 days, and 42 days, respectively. The tissue specificity and ontogenesis expression pattern of the FATP-1 mRNA of yellow-feathered broilers was studied by real-time reverse transcription polymerase chain reaction （RT-PCR）, and the fat deposition laws in different tissues were also compared. A 2,488 bp cDNA sequence of chicken FATP-1 was cloned by RACE （GenBank accession no. DQ352834）, including 547 bp 3＇ end untranslated region （URT） and 1,941 bp open reading frame （ORF）. Chicken FATP-1 encoded 646 amino acid residues, which shared 83.9% and 83.0% identity with those of human and rat, respectively. The results of quantitative PCR demonstrated a constant FATP-1 mRNA expression level in the chest muscle and subcutaneous fat of both male and female broilers at three stages, whereas the expression level of the FATP-1 mRNA in the leg muscle at 42 days was significantly higher than that at 22 days or 29 days. In the abdominal fat of male broilers, the gene expression significantly increased with age, whereas the female broilers showed a dramatic downregulation of FATP-1 expression in abdominal fat at 42 days. This suggested a typical tissue-and gender-specific expression pattern of chicken FATP-1, mediating the specific process of fatty acid transport or utilization in muscle and adipose tissues.

Combination of a <i>Lactobacillus</i>-Based Probiotic and Organic Acids Decrease Egg to Chick Weight Loss and Reduce <i>Salmonella</i>spp. Counts in the Litter of Commercial Broiler Breeders

The effects of supplementing a blend of organic acids (OA) and a lactic acid bacteria (LAB) based-probiotic on egg to chick weight loss (%) and Salmonella spp. recovery counts in the litter of commercial broiler breeders were examined in three independent trials during the years 2013, 2014 and 2015. In each trial, ten thousand birds were divided into two groups of 5000 birds (4500 females and 500 males in each group): Control non-treated group, receiving regular water or treated group, receiving OA and probiotic in the drinking water from 25 to 35 weeks of age. During the ten weeks of evaluation, one thousand fertile eggs or hatched chickens in each trial respectively, were evaluated to obtained, hatching set weight, transferred egg weight, and hatching chick weight, to estimate the difference between egg to chick weight loss (%). Besides, in trial 2 (2014) and trial 3 (2015), litter samples were collected to evaluate Salmonella spp. counts. The supplementation of OA and probiotic during ten consecutive weeks significantly decreased the egg to chick weight loss (%) when compared with the control non-treated groups in all three trials evaluated. Interestingly, at the end of the trials 2 and 3, no counts of Salmonella spp. in the litter were detected. In contrast, control-non treated groups resulted in 4.30 and 4.24 Log10 of Salmonella spp. in trials two and three respectively. The results of the present study suggest that supplementation of OA and a LAB-probiotic for ten consecutive weeks decrease the egg to chick weight loss (%) and reduce Salmonella spp. counts in the litter of commercial broiler breeders. Higher initial body weight in broiler chickens and reduction of Salmonella spp., clearly justify the use of the combination of these products, as alternatives to antibiotics.

Effect of Bee Pollen on Reproductive Performance of Broiler Breeders

[Objective]The paper was to verify whether chestnut bee pollen can be used as feed for breeding chickens and its appropriate addition proportion.[Method]A total of 92444-week-old Ross 308 broiler breeders of parent generation with a male to female ratio of 1∶10 were randomly divided into 4 groups,with 3 replicates in each group and 7 cocks and 70 hens in each replicate.The broiler breeders in the control group were fed with the basal diet,and those in experimental groups were fed with the diets supplemented with 0.5%,1.0%and 1.5%chestnut bee pollen.The feeding trial lasted 35 d.[Result]Addition of chestnut bee pollen at different proportions improved the laying rate of breeder hens in different degrees.The experimental group supplemented with 1.5%chestnut bee pollen increased the laying rate by 9.1%,reduced the rate of unqualified eggs(broken eggs,cracked eggs,thin shelled eggs and hard shelled eggs)by 71.4%,increased the fertilization rate of hatching eggs and healthy chick rate by 4.4%and 5.2%,and improved the concentrations of testosterone(T),follicle stimulating hormone(FSH)and luteinizing hormone(LH)in breeder cocks by 60.8%,32.3%and 61.4%,respectively.Statistical analysis showed that the results were significantly different.[Conclusion]Addition of chestnut bee pollen at certain concentration can improve the reproductive performance of breeder cocks and breeder hens,and improve the body immunity.

Live and Inactivated Salmonella Enteritidis Vaccines:Immune Mechanisms in Broiler Breeders

Salmonella is a ubiquitous pathogen which, in addition to causing poultry diseases, has a growing zoonotic impact. It has demanded the implementation of diverse control strategies, in which vaccines play a major role. The understanding of the immune pathways elicited by the different vaccines is important, contributing for the establishment of strong immune correlates of protection, for instance. With the purpose of determining the dynamics of the humoral and cellular immune responses to vaccination, broiler breeders (Cobb Slow) were immunized with live or inactivated vaccines against Salmonella Enteritidis. Lymphocyte and macrophage subsets were analyzed in the peripheral blood by flow cytometry and antigen-specific circulating IgY and mucosal IgA were quantified. The markers analyzed by flow cytometry were CD8/CD28, CD4/TCRVβ1, Kul/ MHC II and Bu-1. Both live and inactivated vaccines induced an increase in the proportion of circulating monocytes (Kul+MHCII+) in some time points compared to non-vaccinated controls. However, whereas the live vaccine leads to an increase in CD8-CD28+ and Bu-1+ lymphocytescompared to the control group, the inactivated vaccine prompteda reduction in the percentage of severalleucocyte subsets (Kul-MHCII+, Bu-1+, CD8+CD28+, CD8-CD28+, CD4+TCRVβ1-, CD4+TCRVβ1+, CD4-TCRVβ1+) after the boost dose. Both vaccines induced specific serum IgY and mucosal IgA production;however, the inactivated vaccine stimulated higher titers in a shorter period. These results contribute to the understanding of mechanisms of action of live and inactivated Salmonella vaccines in chickens.

Effect of in ovo zinc injection on the embryonic development, tissue zinc contents, antioxidation, and related gene expressions of broiler breeder eggs

Two experiments were conducted to investigate the effect of in ovo zinc （Zn） injection on the embryonic development, tissue Zn contents, antioxidation and related gene expressions of fertilized eggs of Arbor Acres broiler breeders. Experiment 1 was conducted to determine an optimal embryonic age for early in ovo injection. A total of 720 fertilized eggs with similar weights were randomly allotted to 4 treatments with 6 replicates per treatment and 30 eggs per replicate in a completely randomized design. The eggs were injected with 0.1 mL sterilized water at 3, 6 and 9 embryonic days of incubation （E3, E6 and E9） or non-injection （the control）, respectively. The results from experiment 1 showed that E3 and E6 injections increased （P〈0.05） the embryonic mortalities, and decreased （P〈0.05） hatchabilities compared to the non-injected control, but no differences （P〉0.05） between E9 injection and the non-injected control were observed in either embryonic mortality or hatchability. The findings suggest that the E9 is the optimal embryonic age for early in ovo injection. In experiment 2, a total of 672 fertilized eggs with similar weights were randomly allocated to 7 treatments with 6 replicates per treatment and 16 eggs per replicate in a completely randomized design. The eggs were injected with 0 （the negative control）, 50, 100, 150, 200, or 250 μg Zn/egg as reagent grade ZnSO4.7H20 in a 0.1-mL solution, or non-injection （the positive control）, respectively at E9-10. The results from the experiment 2 demonstrated that no differences （P〉0.05） among 50 and 100 μg Zn/egg groups and the negative control were observed in the embryonic mortality and hatchability, however, the injection of 200 μg Zn/egg increased （P〈0.05） the embryonic mortality, and injections of 150 and 200 μg Zn/egg decreased （P〈0.05） hatchabilities compared with the controls. The embryonic tibia Zn contents at E20 were increased （P〈0.05） by injections of 150, 200 and 250μg Zn/egg. Zinc injection did not affect （P〉0.05） malonaldehyde （MDA） contents, copper- and Zn- containing superoxide dismutase （CuZnSOD） activities and mRNA expression levels in the liver and heart of chick embryos at E15 and E20. Compared with the negative control, injections of 50, 150 and 200 μg Zn/egg up-regulated （P〈0.05） themetallothionein （MT） mRNA expression levels in the embryonic liver at E20. These results indicated that in ovo Zn injections increased Zn contents in the embryonic tibia and MT mRNA expression levels in the embryonic liver at E20, however, injections of 150-200 μg Zn/egg were harmful to the embryonic development.

Effect of Dietary Nitrogen Corrected-True Metabolism Energy and Digestible Amino Acids on Broiler Breeder Reproductive Performance

A study was conducted to determine the effects of dietary digestible amino acids of feedstuffs and true metabolizable energy corrected for nitrogen on broiler breeder performance in 50 weeks to 64 weeks of age. 140 females and 20 males broiler breeders in 4 treatments with 5 replicates （7 females with a male） were used in the form of a completely randomized trial design 2 ~ 2 factorial. Four experimental diets were formulation based on two factors, first factor was included, two types of Apparent and True Metabolizable Energy corrected for Nitrogen （AMEn and TMEn） and the second factor was included, two types of Total Amino Acids （TAA） and Digestible （DAA） of feedstuffs. The result showed that egg weight, egg production （%） and egg mass （g/hen/day） was significantly different which was affected by diets formulation based on energy and interaction between energy and amino acids （P 〈 0.01）. Treatment 2 （AMEn ＋ DAA） was at the highest level significantly different （P 〈 0.01） in egg weight 68.97 g, egg production 62.45%, and egg mass 43. i g/hen/day. Hatching eggs were significantly different which was affected by diet formulation based on amino acids. Fertility, hatchability and number of chicks per hen were significant different, that were affected by diet formulation based on energy （P 〈 0.05）. Interaction between two factors, were significantly different in two reproductive traits fertility and hatchability （P 〈 0.05）. This experiment showed that diet formulation based on AMEn and DAA for broiler breeder was better and significant on performance.

Characterization of Lay Phase in Three Genetic Types of Heavy Broilers Breeder in Tropical Conditions

The objective of the present work is characterizing some parameters in the lay phase in the lines of heavy broilers breeder Cobb Avian 48, Arbor Acres Plus and Ross 208, reared under the same commercial conditions in the tropics. Monitored three batches of approximately 18,000 females each （one for each genetic type）, from weeks 24 to 64, according to the conditions of handling and power described by the generic lines distribution companies. Although no differences were found for feed intake, Cobb Avian was presented a lower rate of feed conversion, being also that presented the highest percentage of implementation and production of incubables eggs, which meant that it was in line with the highest cumulative production of chickens by bird and week for tropical conditions studied. To adjust the lay data to a Gorssman model, in order to predict the parameters that characterize the lay modeling, estimated the best behavior for Cobb Avian 48 females, because while it takes more time to reach the level of putting constant （5.30 weeks） and maintain it for less time （2.4 weeks）, they manage to put constant high （79.11%） level, considering that the largest number of eggs per bird （171.19 vs. 164.54 and 160.11 in Arbor Acres and Ross 208, respectively）.

Detection of Mycoplasma synoviae Infection in Broiler Breeder Farms of Morocco Using Serological Assays and Real Time PCR

Mycoplasma synoviae （MS） is an economically important pathogenic agent of chickens, causing air sacculitis and synovitis. The diagnosis and monitoring of M. synoviae infection is usually made using serological assays, while confirmative diagnosis is made by isolation and identifcation of the organism, because of the cross reaction between M. gallisepticum and M. synoviae. This study was conducted from 2011 to 2013 during which l l broiler breeder flocks were sampled. These farms were located in all regions of morocco, The sampling was conducted as follows： Farms were visited on day one old chicks ＂day of importation from Europe＂. 20 to 60 ＂chicks＂ were randomly sampled. At the age of 8, 16, 32 and 56 weeks, 60 blood samples and 60 tracheal swabs were collected at each sampling. The serological screening was performed using Rapid Slide Agglutination （RSA） according the OIE protocol and Indirect EL1SA （IDEXX） according the manufacturer＇s instructions. The molecular diagnosis was performed using a commercial kit of a duplex real time PCR （Life Biotechnology）. The results revealed that one day old chicks were negative to MS by RSA and PCR, however they have a variable stock of maternal antibodies （Ig-Y） detected by iELISA. The seroprevalence found by RSA is variable and increase with the age （Sth week： 55%, 16th week： 91%, 32tb and 56th week： 100%）, the same profile was traced by PCR （Sth week： 36%, 16th week： 64%, 32th week： 82%, 56th week： 100%）, however, all farms were positive by iELISA, from the first day to 56th weeks. These results show that MS infections are very frequent and very widespread among poultry breeder flocks, and showed a perfect agreement between serological tests and Real time PCR starting from 32th week of age.

江苏省肉种鸡场禽多杀性巴氏杆菌流行病学调查

为了解江苏省禽多杀性巴氏杆菌流行情况,促进肉种鸡场的禽多杀性巴氏杆菌病防控,研究通过细菌鉴定方法、PCR检测、荚膜血清学分型、致病性分析以及药物敏感性试验,对分离自江苏省17个肉种鸡场的禽多杀性巴氏杆菌进行菌落形态、培养特性、生化发酵、荚膜型、菌落荧光型、药敏性等生物学特性研究,并对部分种鸡场进行血清学检测。结果显示:共鉴定13株禽多杀性巴氏杆菌,所有分离株荚膜分型均为A型,菌落荧光观察均属于强毒株;分离株对氨基糖苷类药物和氯霉素类药物具有一定的耐药性,而对β-内酰胺类药物高度敏感;确诊种鸡场阳性率显著高于未确诊种鸡场(P<0.01)。研究表明,江苏省部分地区肉种鸡场存在荚膜A型多杀性巴氏杆菌流行,强毒株比例较高,但耐药性较弱。

冬季不同最小通风量模式对肉种鸡育雏育成期生长性能及环控能耗的影响

为研究冬季不同最小通风量模式对肉种鸡育雏育成期舍内环境、生长性能以及环控能耗的影响,试验测试了间歇式通风和连续式通风两种不同的最小通风量通风控制模式,分别比较了两种模式下鸡舍内主要环境质量参数、环控能耗、体重均匀度和抗体效价。结果显示:第一周,连续通风温度高于间歇通风(P>0.05),相对湿度显著低于间歇通风(P<0.05),二氧化碳浓度显著高于间歇通风模式(P<0.05),第2~10周,连续通风温度极显著高于间歇通风(P<0.01),相对湿度极显著低于间歇通风(P<0.01),二氧化碳浓度极显著高于间歇通风模式(P<0.01),同时连续通风鸡舍内环境参数波动度小于间歇通风;试验期间连续通风环控总能耗(7036.01 kW·h)低于间歇通风(7633.02 kW·h),并且连续通风种鸡体重均匀度优于间歇通风;H5N1亚型禽流感病毒抗体效价显著高于间歇通风(P<0.05),H7N9亚型禽流感病毒抗体效价极显著高于间歇通风(P<0.01)。研究表明,冬季肉种鸡育雏育成期采用连续通风的最小通风量模式对比间歇通风的最小通风量模式,可以获得更加稳定的舍内环境,雏鸡生长性能以及免疫效果更优,且能源消耗更少。

棉粕源菌酶协同发酵饲料在肉种鸡生产中的应用研究

本研究旨在探讨棉粕源菌酶协同发酵饲料对产蛋后期肉种鸡生产性能与氮磷排泄率的影响。试验选择42周龄罗斯(Ross)308肉种鸡群,随机分为对照组和试验组。试验预试期1周,正试期16周。在试验过程中,对照组饲喂玉米-豆粕型基础日粮,试验组用8%的棉粕源菌酶协同发酵饲料代替等量的基础日粮。结果表明,与对照组相比,试验组肉种鸡的产蛋率、合格种蛋数显著提高(P<0.05),死淘率显著降低(P<0.05),种蛋受精率有提高的趋势(P=0.057),氮排泄率显著下降(P<0.05),磷排泄率有下降的趋势(P=0.072)。由此可见,在本试验条件下,用8%的棉粕源菌酶协同发酵饲料代替等量的基础日粮可以显著提高肉种鸡生产的经济效益与社会生态效益。

基于16S rDNA分析饲喂唾液乳杆菌XP132对白羽肉种鸡肠道菌群的影响

旨在评估1株替抗专利菌株唾液乳杆菌XP132对健康白羽肉种鸡肠道菌群的影响。选取12只6月龄白羽肉种鸡,随机平均分为试验组和对照组,每组6只。试验组白羽肉种鸡每日饲喂活菌数为1×10^(9)CFU的唾液乳杆菌XP132发酵液,对照组饲喂PBS,连续饲喂4周后,基于16S rDNA测序方法,比较两组鸡肠道菌群发生的相对改变。结果表明,在饲喂唾液乳杆菌XP132后,通过α多样性分析物种丰富度,试验组菌群丰富程度高于对照组。在菌群组成的属水平上,饲喂唾液乳杆菌XP132的肉种鸡肠道菌群中,螺旋体科NK4A136属、梭状芽胞杆菌属、副拟杆菌属、罗氏菌属等有益物种丰度增加;在种水平上,饲喂唾液乳杆菌XP132组的肉种鸡肠道菌群中乳杆菌、拟杆菌、鼠李糖乳杆菌类等有益物种丰度增加。结果提示,本试验条件下,饲喂唾液乳杆菌XP132改变了白羽肉种鸡肠道菌群的丰富度,增加了有益菌菌群的物种丰度。

两段式“全进全出”制笼养肉种鸡场空舍管理方案

目前养鸡场多数采用两段式“全进全出”制笼养饲养模式,鸡舍空舍管理作为其中一个关键环节,通过对鸡舍内、外环境及设备进行清理、消毒、维护,能够有效净化环境、减少疾病、提升后备鸡群经济效益,对参与配合重大动物疫病防控的意义重大。但部分养殖户对空舍管理的概念认知不足,对空舍管理缺乏足够的重视。为此,全面综述了两段式“全进全出”制笼养肉种鸡场空舍管理前、中、后期的管理措施,以期为广大家禽养殖人员提供参考。

一株肉种鸡源鸭疫里默氏杆菌分离鉴定及致病性研究

为探究鸭疫里默氏杆菌对鸡的致病力,试验采集疑似感染鸭疫里默氏杆菌的病死肉种鸡肝脏进行病原的分离培养与纯化、革兰氏染色、生化试验、血清型鉴定、16S rRNA基因测序分析及药敏试验,并将分离菌株在SPF鸡、樱桃谷鸭上进行致病性试验。结果显示:分离到1株血清1型鸭疫里默氏杆菌,该菌株与鸭源、鸡源、鹅源鸭疫里默氏杆菌的相似性分别为99.24%~99.47%、99.16%~99.31%、99.04%~99.20%;该分离株对恩诺沙星、卡那霉素、头孢噻肟、多黏菌素B和多西环素较为敏感,对SPF鸡致病性较弱,可引起一过性精神沉郁和泡沫粪,对樱桃谷鸭有较强的致病性,可引起死亡和严重的纤维素性心包炎、肝周炎和气囊炎。研究表明分离的肉种鸡源RA对鸡致病力相对较弱,结果为临床鸡群感染RA的诊断与防控提供参考。

秋葵发酵液对肉种鸡生产性能、肠道屏障及微生物组成的影响

试验旨在研究黄秋葵发酵液对肉种鸡生产性能、肠道屏障和微生物组成的影响。试验选取190日龄爱拔益加(AA)白羽肉种鸡40只随机分为对照组和黄秋葵发酵液(饲粮添加1%黄秋葵发酵液),每组5个重复,每个重复4只。试验期为49 d,其中预试期7 d,正试期42 d。试验结束后,收集盲肠组织和肠道内容物采用RT-qRCR检测肠道屏障相关基因(ZO-1、Claudin-1和Occludin)表达水平,ELISA检测肠道内容物中细胞因子含量,并且对肠道微生物细菌16S rRNA基因V3-V4区进行高通量测序以检测盲肠中微生物的组成。结果显示:饲粮添加黄秋葵发酵液显著提高白羽肉种鸡平均蛋重、日产蛋率和双黄蛋率(P<0.05),但对料蛋比和平均日增重没有显著影响(P>0.05);与对照组相比,FOP组白细胞介素-6(IL-6)和白细胞介素-1β(IL-1β)含量显著降低(P<0.05),白细胞介素-4(IL-4)和白细胞介素-10(IL-10)含量显著升高(P<0.05或P<0.01),肠道ZO-1、Claudin-1、Occludin基因表达水平显著上调(P<0.05)。物种注释结果发现,在门水平,厚壁菌门(Firmicutes)和拟杆菌门(Bacterodietes)占比最高,与对照组相比,黄秋葵发酵液组厚壁菌门相对丰度升高(P<0.05),而拟杆菌门相对丰度下降(P<0.05);在属水平,黄秋葵发酵液组乳杆菌属(Lactobacillus)和梭杆菌属(Fusobacterium)相对丰度升高(P<0.05或P<0.01),拟杆菌属(Bacteroides)和罗姆布茨菌属(Romboutsia)相对丰度降低(P<0.05或P<0.01)。KEGG富集通路分析表明,与对照组相比,黄秋葵发酵液组显著上调的通路主要涉及到抗生素的生物合成与调节机制、胆汁酸的生物合成等,显著下调的通路涉及到细胞凋亡、鞭毛组装以及细菌的趋化性等。研究表明,在本试验条件下,饲粮添加1%黄秋葵发酵液能够显著提高白羽肉种鸡平均蛋重、产蛋率和双黄蛋率,改变肠道内容物微生物区系组成,提升肠道屏障功能,改善肠道免疫微环境。

Dietary L-theanine alleviated lipopolysaccharide-induced immunological stress in yellow-feathered broilers

L-theanine, a natural nonprotein amino acid with a high biological activity, is reported to exert anti-stress properties. An experiment with a 3 ? 2 factorial arrangement was conducted to investigate the effects of dietary L-theanine on growth performance and immune function in lipopolysaccharide(LPS)-challenged broilers. A total of 432 one-day-old male yellow-feathered broilers were randomly assigned to 3 dietary treatments(control, antibiotic and L-theanine diets) with 2 subgroups of each(6 replicate cages;12 birds/cage). Birds from each subgroup of the 3 dietary treatments were intra-abdominally injected with the same amount of LPS or saline at 24, 25, 26 d of age. Both dietary L-theanine and antibiotic improved(P < 0.05) the growth performance of birds before LPS injection(d 1 to 21). The effect of dietary L-theanine was better(P < 0.05) than that of antibiotic. Lipopolysaccharide decreased feed intake(FI) and body weight gain(BWG) from d 22 to 28(P < 0.05), BWG and feed to gain ratio(F:G) from d 29 to 56(P < 0.05), increased mortality in different growth periods(P < 0.05), elevated the levels of serum cortisol, a1-acid glycoprotein(a1-AGP), interleukin-6(IL-6) on d 24 and 25(P < 0.05), reduced immune organ indexes and contents of jejunal mucosal secretory immunoglobulin A(s Ig A) on d 28(P < 0.05). The decreased FI and BWG, as well as increased F:G and mortality in LPS-challenged birds, were alleviated by dietary L-theanine or antibiotic from d 29 to 56 and from d 1 to 56. Dietary L-theanine mitigated the elevated serum a1-AGP level on d 25, serum IL-6 concentration on d 24 and 26, and the decreased jejunal mucosal s Ig A content on d 28 of the LPS-challenged birds. The results indicated that L-theanine had potential to alleviate LPS-induced immune stress in broilers.

1例肉种鸡发生腹水综合征的病理形态学观察

腹水综合征是由多个因素相互作用引起的危害快速生长幼龄肉鸡的一种非传染性疾病,严重制约肉鸡养殖业的发展。肉种鸡出现该病的报道较为罕见,故本研究以某种鸡场发生腹水综合征的37周龄Cobb 500种鸡为研究对象,剖检见肝脏包膜腔积液,肝脏肿大变硬、表面有纤维样渗出物,心脏右心室肥大、扩张,肺严重瘀血、水肿。镜检见肝脏、心脏、肺脏、脾脏、肾脏均出现严重的病理性损伤。在此基础上对其发病原因进行分析,期待为养鸡者在腹水综合征的防控上提供借鉴。

Dietary supplementation with pioglitazone hydrochloride and L-carnosine improves the growth performance,muscle fatty acid profiles and shelf life of yellow-feathered broiler chickens

The present study aimed to investigate the effects of dietary pioglitazone hydrochloride(PGZ)and L-carnosine(LC)supplementation on the growth performance,meat quality,antioxidant status,and meat shelf life of yellow-feathered broiler chickens.Five hundred broiler chickens were randomly assigned into 4 experimental diets using a 2×2 factorial arrangement with 2 PGZ supplemental levels(0 and 15 mg/kg)and 2 LC supplemental levels(0 and 400 mg/kg)in basal diets for 28 d.The feed-to-gain ratio decreased whereas the average daily gain increased with PGZ supplementation.Greater dressing per-centages,contents of intramuscular fat(IMF)in breast and thigh muscles,C18:3n-6,C18:1n-9 and monounsaturated fatty acid(MUFA)percentages of thigh muscle were observed with PGZ addition.Additionally,significant synergistic effects between PGZ and LC on the C18:1n-9 and MUFA contents were found.Supplementation with LC decreased drip loss,cooking loss and total volatile basic nitrogen,and increased the redness(a*)value,the superoxide dismutase and glutathione peroxidase activities in thigh muscles.Moreover,the malondialdehyde content decreased when diets were supplemented with LC,and there was a synergistic effect between PGZ and LC.Additionally,the mRNA abundance of lipogenesis-related genes,such as peroxisome proliferator-activated receptor y(PPARγ),PPARγco-activator 1αand fatty acid-binding protein 3,increased with PGZ supplementation,and relevant anti-oxidation genes,such as nuclear factor erythroid-2-related factor 2 and superoxide dismutase 1,were enhanced with LC supplementation.In conclusion,the results indicated that the supplementation of PGZ and LC could improve the growth performance,antioxidant ability,IMF content,and meat shelf life of yellow-feathered broiler chickens.