Maillard Products Formed from Chicken Fat Oxidants and Amino Acids Act as a Flavor Enhancer in Comminuted Chicken Products

Lipid oxidation and degradation are generally recognized as unfavorable reactions in food processing. However, lipids can be utilized to produce meat-like flavorings through reaction with amino acids after degradation to carbonyls such as aldehydes and ketones. The fatty acids in chicken fat mainly comprise palmitic acid, oleic acid and linoleic acid. After being heated at 120 ~C for 3 h, the degraded carbonyls of chicken fat were reacted with cysteine, alanine, glycine and thiamine to form a chicken-like flavoring. The key aromatic components of the flavoring were identified by GC-MS. In the overall volatile profile, 22 kinds of compound were detected, among which 2-furanmethanol was formed by the Maillard reaction, 1-（2-furanyl）-ethanone by cyclization and 2,4,6-trimethyl-l,3,5-trithiane by the Strecker degradation of cysteine. Dihydro-2-methyl-3（2H）-furanone, dihydro-2-methyl- 3（2H）-thiophenone, 2-acetyl-lH-pyrroline and 4-methyl-5-thiazoleethanol were the degradation products of thiamine. The prepared chicken flavoring was added to comminuted chicken product （CCP）. GC-MS analysis and sensory evaluation showed that the flavor and odor of the CCP were greatly enhanced.

Effects of Chinese Medicine Additive on Promoting Production of Meat Hybrid Chicken and Its Action Mechanism

[ Objective] The aim was to study the effects of Chinese medicine additive HMS on promoting the production of meat hybrid chicken and its action mechanism, so as to provide a scientific basis for the promotion effects of Chinese medicine additive on production. [ Method] Meat hybrid chickens, 7 day-old with similar weight, were randomly divided into four groups. And Chinese medicine feed additive HMS was added to the diet of each group at different proportions. All the chickens were weighed before the test as well as at the end of the 2nd, 3rd, 4^th and 5^th week. The feed consumption was also recorded during the test. Before slaughter, serum samples were collected from the randomly selected chickens for the deter- mination of serum biochemical indexes. Their bursae of Fabdcius and spleens were collected and weighed in order to determine the indexes, of im- mune organs. [ Result] HMS significantly reduced the feed conversion ratio （ P 〈 0.05 ）, very significantly reduced the feed consumptioh （ P 〈 0.01 ）, very significantly improve the content of serum high-density lipoprotein （ P 〈 0.01 ）, significantly increased the activity of serum alkaline phos- phatase （ P 〈 0.05）, very significantly reduced the content of serum urea nitrogen and uric acid （ P 〈 0.01 ）, and significantly reduced the level of serum cholesterol （ P 〈0.05）. There were no significant difference between the test groups and the control group （ P 〉 0.05） in the increase of im- mune organ indexes, but the index of immune organs has increasing trend. [ Conclusion] HMS reduces feed consumption and feed conversion rati- o, improves the feed utilization, and has a role in promoting production. The possible mechanism may be HMS improving the activity of serum alka- line phosphatase and the level of serum high-density lipoprotein, as well as reducing the content of serum cholesterol, urea nitrogen and uric acid in meat hybrid chickens.

An Updated Review on Chicken Eggs: Production, Consumption, Management Aspects and Nutritional Benefits to Human Health

Ancestors of the modern chicken were domesticated from members of the Gallus genus probably 7 to 8 thousand years ago in southeastern Asia. Subsequently, they spread globally for meat and egg production. In the chicken egg, there is a balance of numerous, high-quality nutrients, many of which are highly bioavailable. The egg confers a multitude of health benefits to consumers emphasizing its classification as a functional food. Current global per capita egg consumption estimates approach 9 kg annually but vary greatly on a regional basis. This review deals with global production, consumption, and management aspects such as hygiene, feeding, and housing. Management aspects play key roles in the composition, quality, food safety, and visual (consumer) appeal of the egg. Also the manipulation of egg nutrients and value for human health is discussed.

Effects of "Products of Chicken Embryo" on Growth and Sexual Development in Rats

Products of Chicken Embryo (PCE) such as Ji-Pei-Jing is a kind of food for Chinese children prepard from chicken embryo. Female rats on 21 days were administered with aqueous solutions of Ji-Pei-Jing (1. 2 %, 3 %, 12%, and 48%, respectively) by gavage up to their onsets of puberty.The rats in the control group were treated with distilled water. However, Ji-Pei-Jing treatment exerted some effects on sexual mauration in the immature female rats. Essentially, the effects showed a dose-response tendency with an inverted 'U' shape.The age of vopnal opening for gnup treated with Ji-Pei-Jing was significantly earier than that to the control. Its uterus weight/b. w. ratio also significantly increased on day 30 and at the first estrus. There were significantly increases in the adrenal weight/b. w. raio of 30-day-old rats that were treated with 3%, 12%, and 48% Ji-Pei-Jing. The rats treated with 48% Ji-Pei-Jing had significantly lesser ovary weight.b.w. radio on day 30, too. The rats treated with Ji-Pei-Jing could normally ovulate at the first estrus, and no significant differences were observed during estrous cycles.The effects of PCE on serum levels of K, P, LH in 30-day-old nds and FSH in 28-day-old ras were elevated significantly by 3 % Ji-Pei-Jing treatment. It appeare that the effects of PCE result from interaction of contained complex physiologically active substances. Steriods, especially estradio-17β,possibly Play a key role, and polpeptide hormones may also exert important effects.

The Correlation between Polydactyly Phenotype and Product Quality of Beijing Fatty Chickens

[ Objective] This study aimed to investigate differences in product quality among Beijing fatty chickens with different polydactyly phenotypes. Based on the comparative analysis of production performance, egg quality and muscle quality characteristics, the correlation between polydactyly phenotype and product quali- ty of Beijing fatty chickens was analyzed, aiming at providing the reference for development and utilization of product quality and breeding of Beijing fatty chickens. [ Method] Egg laying/meat dual-purpose type Beijing fatty chickens were selected and divided into three groups （bilateral four-toed, unilateral five-toed and bilat- eral five-toed） with four replications, 60 chickens per replications, 240 chickens per group. The production performance （weight, laying rate and egg weight）, egg quality （Haugh unit） and muscle quality （pH, water-holding capacity, Warner-Bratzler shear force, TPA, nucleotide metabolites） characteristics of Beijing fatty chickens were determined. [ Result] The weight of 120-d-old and 240-d-old bilateral five-toed Beijing fatty chickens was slightly higher than that of bilateral fourtoed and unilateral five-toed Beijing fatty chickens, with no significant difference （P 〉0.05） ; egg weight of 160-d-old bilateral five-toed Beijing fatty chickens was significantly higher than that of bilateral four-toed and unilateral five-toed individuals （ P 〈 0.05 ）. Water-holding capacity of leg muscles of bilateral five-toed Bei- jing fatty chickens was significantly superior to that of unilateral five-toed and bilateral four-toed individuals （P 〈0.05 ）. The hardness, gumminess and chewiness of leg muscles of bilateral five-toed Beijing fatty chickens were significantly lower than that of unilateral five-toed and bilateral four-toed individuals （ P 〈 0.05 ）, but the coherence and elasticity were remarkably higher compared with unilateral five-toed and bilateral four-toed individuals （ P 〈 0.05 ）. Warner-Bratzler shear force of leg muscles of bilateral five-toed Beijing fatty chickens was significantly higher than that of other individuals （ P 〈 0.05 ）. There was no significant difference in flavor substances among Beijing fatty chickens with different polydactyly phenotypes （P 〉0.05）. [ Conclusion] At early stage, the weight and egg weight of fivetoed Beijing fatty chickens were slightly superior to that of four-toed individuals. In addition, Beijing fatty chickens with different polydactyly phenotypes displayed excellent muscle quality. Overall, leg muscle quality of Beijing fatty chickens exhibited a greater correlation with polydactyly phenotype than chest muscle quality.

Correlation between Egg Production Traits and Broodiness Traits in Shiqiza,Langya and Luqin B2 Chickens

[ Objective] To investigate the relationship between the egg production traits and broodiness of Shiqiza, Langya and Luqin B2 chickens. E Method] Three chicken breeds, Shiqiza chickens （a breed preserved by Shandong Academy of Agricultural Sciences）, Langya chickens （a local breed in Shandong Province） and Luqin B2 chickens （a cultivated breed） were selected. Then their broodiness traits were observed and the egg productions were analyzed. Finally, the relationships between the egg production traits and broodiness were analyzed by SAS software. [ Result] The Shiqiza, Langya and Luqin B2. chickens were broody and their broodiness rate was 15.80%, 2.24% and 6.95%, respectively. Compared with the non-broody chickens, the egg productions of Shiqiza, Langya and Luqin B2 chickens were respectively decreased by 17.16%, 1.53% and 10.8% at the age of 43 weeks. The three breeds had significant differences in repeats of broody cycles （ P 〈 0.05）, and extremely significant differences in the broodiness duration, the the first day of broodiness, the age at the first egg, total amount of abnormal eggs and amount of double- yolked eggs （P 〈 0.01 ）. [Conclusion] The broodiness is a main factor affecting egg production traits. The degree of effects of broodiness on egg production traits is decreased successively in Shiqiza chicken, Luqin B2 chicken and Langya chicken.

Correlation between DRD2 Gene Polymorphism and Early Egg Production Performance of Libo Yaoshan Chicken

To improve egg production performance of local chicken breed in Guizhou Province, Libo Yaoshan chicken, with dopamine receptor 2 （ DRD2 ） as one of the candidate genes, we detected its genetic variation in 196 Libe Yaoshan hens using PCR-SSCP （single-strand conformation polymorphism） and sequencing method, and analyzed the correlation between genetic variation and egg production traits. The results showed that TT and TG genotypes in mRNA SNlX）62 （C→T） loci of the DRD2 gene had extremely significant difference in egg production at 38 weeks age （P 〈0.01 ）, and significant difference in egg weight at 300 days age （P 〈0.05 ）. The single nucleotide polymorphisms （SNPs） mutation induced synonymous mutation of the 312th amino acids （leucine） in DRD2 protein, from L （CTG） to L （TI＇G）. The mRNA SNP962 （C→T） loci had a larger genetic effect on egg production at 38 weeks age, and could be used as a molecular marker in early breeding of Libo Yaoshan chicken.

Interferon-γ acts as a regulator in the trade-off between phagocytosis and production performance in dwarf chickens

Background: Interferon-γ(IFN-γ) is critical for innate and adaptive immunity against viral and bacterial infections. IFN-γ reportedly affects the phagocytic ability of monocytes and macrophages as well as regulates pituitary function in humans and mice. The present study analyzed the impact of IFN-γ on monocyte and macrophage phagocytosis, production performance, and pituitary function in vivo and in vitro(in dwarf chickens). IFN-γ was injected into dwarf chickens through a vein, and then, the laying rate, average egg weight, and levels of follicle-stimulating hormone(FSH) and IFN-γ were measured in treatment and control groups. For the in vitro experiment, the pituitary tissues were supplemented with IFN-γ, and the m RNA expression levels of follicle-stimulating hormone beta subunit(FSH-β), interferon gamma receptor 1(IFNGR1),and interferon gamma receptor 2(IFNGR2) in the pituitary were assessed.Results: Monocyte and macrophage phagocytosis product(PP) was decreased by IFN-γ treatment in a dose-dependent manner in vitro. In the in vivo experiment, the level of IFN-γ in the treatment group was higher than that in the control group at 7 d(P < 0.05), 14 d(P < 0.01), and 21 d(P < 0.01) post-injection.Compared with the control group, monocyte and macrophage PP was lower in the treatment group after injection(P < 0.01). The laying rate was higher in the treatment group than in the control group at 2 and3 wk post-injection(P < 0.05). There was a significant difference between the treatment and control groups in the levels of FSH at 1, 3, 7, and 14 d post-injection(P < 0.01). In the in vitro experiment, increased m RNA expression levels of FSH-β, IFNGR1, and IFNGR2 were observed in the treatment group after stimulation with100 U/m L IFN-γ for 24 h compared to those in the control group(P < 0.05).Conclusions: IFN-γ inhibited the phagocytosis of monocytes and macrophages; up-regulated the m RNA expression levels of the FSH-β, IFNGR1, and IFNGR2; enhanced the secretion of FSH; and improved the laying rate. IFN-γ might be an important regulator in the trade-off between the immune effect and production performance in dwarf chickens.

基于机器学习的地方鸡产蛋曲线拟合探索

[目的]本研究探索以机器学习方法对2个地方鸡品系周产蛋率建模,并将其与非线性回归方法比较,旨在提高养鸡生产中产蛋曲线的拟合精度。[方法]产蛋数据采集自地方鸡杂交组合试验群,自22周龄开始统计产蛋数,至50周龄截止。试验鸡于全封闭鸡舍单笼饲养,产蛋期人工补光16 h。试验鸡分为两组,每组150只鸡。第Ⅰ组是黄羽肉鸡合成系,第Ⅱ组是兼用型地方鸡种。以IBM SPSS Statistics 21.0软件中的非线性回归方法拟合产蛋曲线,所用模型包括Logistic模型、McNally模型、杨宁模型以及Grossman模型。以MATLAB R2014a构建机器学习模型,神经网络选用多层感知器,用300次迭代的拟牛顿法训练数据。以贝叶斯最小二乘支持向量机构建产蛋模型,针对正则项系数和核函数参数进行优化。[结果]依据MSE、R 2、AIC评判标准,Grossman模型在4种非线性回归模型中拟合度最好,McNally模型表现最差。McNally模型预测的高峰产蛋率偏离真实值;Logistic模型、杨宁模型以及Grossman模型高峰产蛋率统计值与真实值基本相符。两组试验鸡的模型参数不同,Ⅱ组持续产蛋能力优于Ⅰ组。基于MSE、R 2以及图形评估结果,神经网络优于传统的非线性方程拟合,而支持向量机略好于神经网络。优化后神经网络参数为2个隐藏层,每个隐藏层包含5个神经元。第Ⅰ组支持向量机的正则项系数为30.97,核参数为0.0701;第Ⅱ组支持向量机的正则项系数为566.53,核参数为0.1754.[结论]机器学习方法可用于产蛋模型构建,相比于传统单变量回归方法,机器学习方法可加入更多变量,提供更准确的预测。

Design and Experiment on Environment Friendly Type of Production Equipment of Organic Fertilizer by Chicken Manure

In accordance with current problems such as odor pollution,long production period,consumption of a large amount of manpower and so on existing in chicken manure fermentation ,an environment friendly type of chicken manure fermentation device is designed. The key parameters of the equipment are resonance activated tube and fermenting cellar. Resonance activated tube makes the activated water,which could improve obvi- ously the biodegradation rate of chicken manure. The aerator could provide enough oxygen to microbes,and the agitator could make oxygen evenly distributed across the chicken manure in fermenting cellar. The test shows that this equipment is high-efficiency,and only takes 7 days to make the chicken manure achieve the decomposed requirement. The organic matter content of composted chicken manure is 91.2%,C/N ratio is 18.8, MPN is 0.04, mortality of ascarid egg is 99.6% ,concentrations of NH3 and H2 S are 4.20 and 1.58 mg/m3, furthermore ,there is no offensive smell in the fermenting cellar. Therefore,the study can provide a pollution-free, high-efficiency, manpower saving fermentation equipment for organic fertilizer production by chicken manure in agriculture area.

调理鸡肉中沙门氏菌污染状况调查及抗生素耐药监测

目的:了解近年来潍坊市调理鸡肉中沙门氏菌污染状况,并进行抗生素耐药监测,为食品安全风险评估、安全标准修订提供依据。方法:2023年采集潍坊市市售调理鸡肉35份,按照《食品安全国家标准 食品微生物学检验 沙门氏菌检验》(GB 4789.4-2016)进行沙门氏菌分离鉴定,采用微量肉汤法开展耐药性监测。结果:35份调理肉样品中共有11份检出沙门氏菌,总检出率为31.4%;耐药实验结果显示,调理肉中沙门氏菌对多种抗生素产生耐药性,对氨苄西林、链霉素、头孢唑啉的耐药率最高,分别为93.3%、73.3%和73.3%。结论:潍坊市市售调理鸡肉中存在沙门氏菌污染,分离株对多种抗生素耐药。

The Influence of Selection for Plasma very Low Density Lipoprotein Concentration upon Production Performance in Layer Type Chickens

The chickens studied were from a pure line of brown shell egg-type (YAFA) female grandparents of 17-week-old. Plasima very low density lipoprotein (VLDL) concentration was measured with turbidimetric assay. The experiment results showed that the phenotypic correlations between 29-week or 50-week plasma VLDL concentration and egg production (EP) were positive in the early stage of laying period, but those in the latter stage were negative. Selection for low plasma VLDL concentration will decrease the EP in the early stage of laying period but increase the one in the latter stage. There was a significant negative phenotypic correlation between the age at first egg (AFE) and 18-week body weight (BW). The phenotypic correlation between 29-week plasma VLDL concentration and the AFE was negative. AFE was influenced by BW and body fatness as well. There was significant positive phenotypic correlation between plasima VLDL concentration and body weights (BWs) at the same stage in laying period and the phenotypic correlation was also positive between 29-week plasma VLDL concentration and the BW at middle stage of laying period, indicating that selection for low plasma VLDL concentration would reduce BWs at various stages to different degree.

广西麻鸡卵巢组织中差异lncRNA筛选及ceRNA网络构建

【目的】筛选广西麻鸡卵巢中差异表达的长链非编码RNA(long non-coding RNA,lncRNA)、信使RNA(messenger RNA,mRNA)以及微RNA(microRNAs,miRNA),并进一步筛选出与鸡产蛋性状相关的lncRNA,为后期研究lncRNA对鸡产蛋性状的调控提供理论支持。【方法】根据广西麻鸡从开产到41周龄的产蛋情况筛选出高产和低产的广西麻鸡各3只,并以其卵巢组织为材料,进行转录组测序,使用edgeR和DEseq2软件从测序得到的数据中筛选出差异表达的lncRNA、mRNA以及miRNA,利用miRanda软件和lncRNA的顺式作用分别预测miRNA和lncRNA的靶基因,对差异lncRNA的靶基因进行GO功能和KEGG通路富集分析后,利用Cytoscape(v 3.8.2)软件构建竞争性内源RNA(ceRNA)网络图。利用实时荧光定量PCR验证转录组测序结果。【结果】本研究共获得广西麻鸡卵巢组织中438个差异表达的lncRNAs、18个差异表达的miRNAs以及301个差异表达的mRNAs。对上述差异表达的lncRNA的靶基因进行GO功能和KEGG通路富集分析后发现,其显著富集于激素分泌调节、中胚层形成、中胚层发育以及中胚层形态发生等与产蛋有关的生物过程,以及MARK、甘露糖O-聚糖的生物合成、卵母细胞减数分裂、孕激素介导的卵母细胞成熟以及促性腺激素释放激素等信号通路。通过GO功能和KEGG通路富集分析获得6个与产蛋性状相关的lncRNAs,分别是TCONS_00091814、TCONS_00051866、XR_006939520.1、XR_005839807.1、TCONS_00088588、TCONS_00037324。根据测序结果成功构建出包含9个miRNAs、60个lncRNAs和3个mRNAs的ceRNA网络图,且网络中所有的基因均在低、高产组中差异表达。所选差异表达基因实时荧光定量PCR结果与转录组测序的基因表达水平一致,说明转录组测序结果可靠。【结论】通过RNA测序技术从广西麻鸡卵巢中筛选到了一系列差异表达的lncRNA,并筛选出了6个可能与产蛋性状相关联的lncRNAs,为进一步提高鸡的产蛋性能提供了理论支持。

牛至提取物对肉雏鸡生产性能及其免疫功能的影响试验研究

为研究牛至提取物对肉鸡生产性能及其免疫功能的影响效果。该试验选用210只商品代雏鸡,随机分成3组,A组为空白对照组,B组(30 mg/kg)为中剂量组,C组(60 mg/kg)为高剂量组,4个重复,每个重复10只鸡,用作生产性能测定;另2个重复,每个重复15只鸡,用于不同日龄试验雏鸡免疫器官绝对重量及其指数的研究。结果表明,试验B组、C组促生长率显著高于对照组(P<0.05),B组雏鸡促生长率较高,相反C组促生长率低于B组。B组、C组在3段日龄中分别提高增重11%和6.7%,说明促生长率随日粮添加水平的提高而降低。进一步说明在肉雏鸡日粮中添加牛至提取物可以促进肉雏鸡的生长率,当牛至提取物添加水平为30 mg/kg时,对肉雏鸡的促生长率效果最为显著。为牛至提取物在肉鸡生产上的应用提供理论依据。

饮水型罗勒油-柠檬酸复合制剂对肉鸡的生产性能和肠道菌群的影响

该试验目的在于研究饮水型罗勒油-柠檬酸复合制剂对肉鸡的生产性能和肠道菌群的作用。选用3周龄处州三黄肉鸡150羽,随机分为2组,每组3个重复,每个重复25只。对照组饮用清水;试验组的饮用水中在第1周和第5周全程添加0.1%罗勒油-柠檬酸复合制剂,其余时间段则不添加。两组都饲喂肉用仔鸡中期全价配合饲料。试验期共计7周。结果表明,饮水中添加0.1%罗勒油-柠檬酸复合制剂能够明显提高肉鸡的平均体重和平均日增重,增加第3周时粪便中乳酸杆菌数量,降低大肠埃希氏菌数量;但是第7周时对盲肠菌群数量没有影响。表明饮水中添加0.1%罗勒油-柠檬酸复合制剂能够明显提高肉鸡的生产性能。

Effect of dietary arginine to lysine ratios on productive performance,meat quality,plasma and muscle metabolomics profile in fast-growing broiler chickens

Background: Due to the important functions of arginine in poultry,it should be questioned whether the currently adopted dietary Arg:Lys ratios are sufficient to meet the modern broiler requirement in arginine.The present study aimed,therefore,to evaluate the effects of the dietary supplementation of L-arginine in a commercial broiler diet on productive performance,breast meat quality attributes,incidence and severity of breast muscle myopathies and foot pad dermatitis(FPD),and plasma and muscle metabolomics profile in fast-growing broilers.Results: A total of 1,170 1-day-old Ross 308 male chicks was divided into two experimental groups of 9 replicates each fed either a commercial basal diet(CON,digestible Arg:Lys ratio of 1.05,1.05,1.06 and 1.07 in each feeding phase,respectively) or the same basal diet supplemented on-top with crystalline L-arginine(ARG,digestible Arg:Lys ratio of 1.15,1.15,1.16 and 1.17,respectively).Productive parameters were determined at the end of each feeding phase(12,22,33,43 d).At slaughter(43 d),incidence and severity of FPD and breast myopathies were assessed,while plasma and breast muscle samples were collected and analyzed by proton nuclear magnetic resonancespectroscopy.The dietary supplementation of arginine significantly reduced cumulative feed conversion ratio compared to the control diet at 12 d(1.352 vs.1.401,P < 0.05),22 d(1.398 vs.1.420; P < 0.01) and 33 d(1.494 vs.1.524; P < 0.05),and also tended to improve it in the overall period of trial(1.646 vs.1.675; P = 0.09).Body weight was significantly increased in ARG compared to CON group at 33 d(1,884 vs.1,829 g; P < 0.05).No significant effect was observed on meat quality attributes,breast myopathies and FPD occurrence.ARG birds showed significantly higher plasma concentration of arginine and leucine,and lower of acetoacetate,glutamate,adenosine and proline.Arginine and acetate concentrations were higher,whereas acetone and inosine levels were lower in the breast of ARG birds(P < 0.05).Conclusions: Taken together,these data showed that increased digestible Arg:Lys ratio had positive effects on feed efficiency in broiler chickens probably via modulation of metabolites that play key roles in energy and protein metabolism.

芪枣提取物对余干乌骨鸡生产性能、蛋品质、生殖激素和卵泡发育的影响

为研究芪枣提取物对余干乌骨鸡生产性能、蛋品质、生殖激素和卵泡发育的影响,试验选用240日龄体况良好的余干乌骨鸡120只,随机分成4个组,每组6个重复,每个重复5只。对照组饲喂基础日粮,试验组在基础日粮中分别添加100、200、400 mg/kg芪枣提取物,试验期为56 d。结果表明:(1)芪枣提取物对余干乌骨鸡的产蛋率、料蛋比、平均蛋重和平均日采食量无显著影响(P>0.05)。(2)余干乌骨鸡蛋壳黄度随芪枣提取物水平的增加呈线性增加(P<0.05),哈氏单位、蛋黄指数和蛋壳红度呈二次曲线变化(P<0.05)。(3)试验第28天,余干乌骨鸡血清中雌二醇(E2)含量随芪枣提取物添加水平增加呈二次曲线变化(P<0.05),促卵泡素(FSH)和促黄体生成素(LH)含量随芪枣提取物添加水平增加呈线性增加(P<0.05);试验第56天,芪枣提取物对余干乌骨鸡血清中E2、FSH和LH含量无显著影响(P>0.05)。(4)余干乌骨鸡卵巢雌激素受体β(ESRβ)和促性腺激素释放激素(GnRH1)随芪枣提取物水平的增加呈线性增加(P<0.01),促卵泡素激素受体(FSHR)随芪枣提取物水平的增加呈二次曲线变化(P<0.05)。综上所述,饲粮中添加芪枣提取物可以提高余干乌骨鸡蛋品质、生殖激素含量和卵泡发育相关激素受体基因表达水平。本试验条件下,以200 mg/kg添加量效果最好。

热应激对鸡生产性能、血清生化和肠道微生物影响研究进展

热应激是全球鸡生产面临的重要环境应激挑战之一,它是动物受到外界环境影响时所做出的一系列的非特异性应激反应的总和。热应激会导致鸡的采食量减少、生长性能下降、血液生化指标改变和肠道微生物菌群紊乱,严重影响鸡的生产力。热应激还能够降低鸡的防御机制和免疫功能,增加炎症因子表达,引起机体抗氧化指标升高,并显著影响鸡肠道菌群组成和多样性,其中大肠杆菌和甲烷芽孢杆菌为重要的预测因子,起到重要的预见作用。鸡在热应激环境下的生理调节包括心率增加、呼吸急促及体内氧化代谢增强等症状。在实际生产过程中,通过加强饲养管理、改善饲养环境和添加抗应激物,如微量元素锌及各种维生素,可有效缓解热应激带来的危害。作者综述了热应激对鸡生产性能、血清生化、抗氧化及肠道菌群结构组成等相关指标的具体影响,为鸡饲养管理过程中热应激预防提供一定的理论依据。

湘东鸡生产性能分析

为了解湘东鸡选育的效果,试验对湘东鸡外观、体重、体尺与蛋品质等进行测定,并与湘黄鸡、桃源鸡进行比较。结果表明:1)湘东鸡有髯、红色单冠、冠齿6~8个;公鸡鸡冠大、厚、多数直立,少部分向一侧倒下;母鸡鸡冠多数向一侧倒下;湘东鸡98%以上的颈羽、背羽、鞍羽、腹羽为黄麻色;84%的尾羽为黑色;58%的主翼羽为黄麻色;93%为白皮;76%为青胫;2)300日龄湘东鸡:体斜长、龙骨长、体重、胸深、胸宽、胫长极显著小于230日龄的桃源鸡(P<0.01);体重、胫围极显著大于同日龄的湘黄鸡(P<0.01);体斜长极显著小于同日龄的湘黄鸡(P<0.01);不同年龄阶段,湘东鸡平均体重均大于同龄湘黄鸡;3)150日龄湘东鸡的蛋重、蛋纵径、蛋横径显著大于湘黄鸡(P<0.05),显著小于桃源鸡(P<0.05);300日龄湘东鸡,蛋重、蛋黄颜色显著大于湘黄鸡(P<0.05),水分含量小于湘黄鸡蛋,粗蛋白、粗脂肪大于湘黄鸡蛋,但差异都不显著(P>0.05);湘东鸡蛋壳颜色较为混杂,还未达到蛋壳颜色为白色或粉色的目标。说明,湘东鸡在生长速度、体重、蛋品质等方面优于湘黄鸡,也优于丝羽乌骨鸡、清远麻鸡等一些地方鸡品种,且湘东鸡鸡蛋营养价值与口感不差于湘黄鸡,后续还需提高品种的均匀度、蛋壳颜色的一致性。

消费者对岭北盐焗鸡的认知、评价及购买行为分析

对浙江省绍兴市诸暨市岭北镇进行实地考察及线上线下问卷调查,从消费者行为视角分析岭北盐焗鸡市场。调查结果显示,消费者对岭北盐焗鸡的了解有限,但对其感官评价较为积极,尤其赞赏产品的外观与色泽特征;消费者的价格接受度差异大,但性价比高获得较多消费者认可,产品款式上偏好传统整鸡与原味类型;消费者的购买动机多为尝鲜,岭北盐焗鸡销售受认知局限、价格偏高及口味偏好差异等因素影响。基于上述调查结果,建议加强宣传推广、优化价格策略、丰富产品线,以推动岭北盐焗鸡产业稳健发展。