As a Chinese indigenous chicken breed, Beijing You Chicken is renowned for its high-quality meat and eggs, as well as distinctive morphological features including feathered shanks, beards, and crests. In this study, in order to understand the genetic basis for growth traits of this breed, we performed genome-level analysis for body weight and related morphometric phenotypes in Beijing You Chicken. Totally, we selected 224 adult female individuals at 38 weeks to measure growth traits including body weight, tibia length, and shoulder width. Whole-genome sequencing was performed on all samples, followed by genome-wide association studies (GWAS) in order to identify candidate genes and genomic regions associated with these traits. The results showed that one genomic region on chromosome 4, harboring six genes including NCAPG, KCNIP4, SLIT2, LCORL, CLRN2, and LDB2, was significantly associated with body weight and other related growth traits. Our findings revealed a strong association between these SNPs (single nucleotide polymorphisms) and body size traits, providing critical insights into the genetic basis of body weight traits in Beijing You Chicken and the SNPs could be furtherly applied to marker assistant selection for body weight trait in the local chickens.

Objective: The goal of this study was to investigate the mechanisms of muscle growth and development of three chicken breeds. Participants: Eighteen chickens, including three different breeds with different growth speeds (White Broiler, Daheng, and Commercial Layers of Roman), were used. Methods: Total RNA from breast muscle of these chickens was subjected to a gene expression microarray. Differentially expressed genes (DEGs) were screened and functional enrichment analysis was performed using DAVID. Seven DEGs were confirmed by quantitative reverse transcription PCR. Results: Overall, 8,398 DEGs were found among the different lines. The DEGs between each two lines that were unique for a developmental stage were greater than those that were common during all stages. Functional analysis revealed that DEGs across the entire developmental process were primarily involved in positive cell proliferation, growth, cell differentiation, and developmental processes. Genes involved in muscle regulation, muscle construction, and muscle cell differentiation were upregulated in the faster-growing breed compared to the slower-growing breed. DEGs including myosin heavy chain 15 (MYH15), myozenin 2 (MYOZ2), myosin-binding protein C (MYBPC3), insulin-like growth factor 2 (IGF2), apoptosis regulator (BCL-2), AP-1 transcription factor subunit (JUN), and AP-1 transcription factor subunit (FOS) directly regulated muscle growth or were in the center of the protein-protein interaction network. Pathways, including the extracellular matrix (ECM)-receptor interaction, mitogen-activated protein kinase (MAPK) signaling pathway, and focal adhesion, were the most enriched DEGs between lines or within lines under different developmental stages. Conclusions: Genes involved in muscle construction and cell differentiation were differentially expressed among the three breeds.

为研究传统肉种鸡舍内主要内环境参数时空分布规律,采用自动检测仪器开展舍内主要内环境参数监测,测定期内各环境参数平均值分别为:氨气5.98 mg/m3、二氧化碳1 485.51 mg/m3、硫化氢0.028 mg/m3,温度9.14℃,相对湿度84.54％.从时间上分布,早晚有害气体浓度都较高,与夜间封闭门窗保温有关;从水平分布上,环境参数除二氧化碳外,分布较为均匀;在垂直方向上,舍内有害气体浓度与温度均随测定高度的增加而上升.综合监测表明:传统肉种鸡舍内环境参数虽接近或低于国家相关标准,但均匀度较差,且受舍外环境影响较大,尤其是温度和相对湿度,生产中需要增加通风换气系统以及辅助加热装置.

Background Tibetan chickens living at high altitudes show specific adaptations to high-altitude conditions, but the epigenetic modifications associated with these adaptations have not been characterized. Results We investigated the genome-wide DNA methylation patterns in Tibetan chicken blood by using whole genome bisulfite sequencing. Generally, Tibetan chickens exhibited analogous methylation patterns to that of lowland chickens. A total of 3.92% of genomic cytosines were methylcytosines and 51.22% of cytosines in CG contexts were methylated, which was less than those in lowland chicken (55.69%). Moreover, the base adjacent to the methylcytosines of mCHGs in Tibetan chickens had a preference for T, which was different from that in lowland chickens. In Tibetan chickens, the methylation levels in the promoter were relatively low, while the gene body was also maintained in a hypomethylated state. DNA methylation levels in regions upstream of the transcription start site of genes were negatively correlated with the level of gene expression, and DNA methylation of gene body regions was also negatively related to gene expression. Conclusions We generated the genome-wide DNA methylation patterns in Tibetan chickens and our results will be helpful for future epigenetic studies related to adaptations to high-altitude conditions.

为掌握全封闭式环控鸡舍内主要内环境参数时空分布规律,指导养殖设施设备的设计与布置,采用自动检测仪器对全封闭式环控肉鸡育雏育成舍开展舍内主要内环境参数监测,利用统计软件对监测数据进行分析研究。结果表明:全封闭式环控肉鸡育雏育成舍内环境参数在时间分布上,均匀度好,环境比较稳定,除二氧化碳外,都达到了国家相关标准;空间分布规律,垂直方向上均匀度好,环境比较稳定,除相对湿度外,其他环境参数均随高度升高而升高,水平方向,受风机作用影响温湿度均匀度较差,除相对湿度外,环境参数中部高于前后两端。

为了适时修正育种方案,提高选择效率,试验对大恒优质肉鸡五个品系开展了遗传进展分析.结果表明:14个世代以来对各品系主要性状的选择是有效的,特别是对生长速度的选择未对繁殖性能造成不利影响;第6世代之后,各品系主要性能保持在较高水平,但选育进展明显降低.说明现有育种手段对于维持和巩固大恒优质肉鸡育种目标性状的性能是有效的,要取得更大的遗传进展需及时调整育种方案.

为了研究种公鸡饲喂母鸡料对受精率等繁殖性能的影响,试验选择25周龄健康的S08公鸡60只,随机分成试验组和对照组,分别饲喂母鸡料和公鸡料,28周龄随机选取同舍母鸡2列,每列400只,分别与试验组、对照组公鸡进行人工授精,分别测定受精率、孵化率和健雏率.结果表明:试验组在产蛋前期的受精率明显低于对照组,而在产蛋中期与后期试验组与对照组结果相近;孵化率的趋势与受精率一致;健雏率整个阶段试验组与对照组无明显差异.说明种公鸡饲喂母鸡料对产蛋前期受精率有一定的影响,但对实际生产影响并不大,考虑实际因素种公鸡可以饲喂母鸡料.

Objective] To study the growth and carcass traits of five strains of Daheng high-quality meat chicken and provide references for breeding high-quality meat chicken strains further.[ Method] Five strains of Daheng high-quality meat chicken( A,B,C,A ×B and C ×B) were selected as research objects to feed under the same conditions for 10 weeks and determine the slaughter weight and meat performance . [Result] Besides abdominal fat weight,the live body weight, slaughter weight,semi-eviscerated weight, eviscerated weight, breast muscle weight and leg muscle weight of cocks of five strains were all significantly or extremely significantly higher than that of hens.The carcass per-centage of cross line A ×B and C ×B was above 85%,and the eviscerated percentage of cross line A ×B and C ×B was above 65%.And cross line A ×B and C ×B had better meat performances.The carcass percentage, semi-eviscerated percentage, eviscerated percentage, breast muscle percentage of cross line A ×B were higher than that of cross line C ×B.[ Conclusion] There were differences of growth and car-cass traits among different stains of high-quality meat chicken.The cross line A ×B had higher growth speed, so it was suitable to be popular-ized in the markets with higher growth speed demands of high-quality meat chicken.

肌球蛋白重链(MHC)作为肌球蛋白的组成单位,在维持肌细胞的正常工作中发挥重要作用.研究利用实时荧光定量PCR方法对MYH7基因在鸡不同组织与生长发育阶段的表达差异进行了比较.结果显示:鸡腿肌和胸肌组织中MYH7基因的表达量都极显著高于肝脏组织,在肝脏组织中几乎没有表达,在胸肌组织中表达量最高;鸡胸肌组织中MYH7基因在10周龄表达量高于2和6周龄,且在10周龄表达量显著高于6周龄.由此推测该基因在肌肉组织的生长和发育过程中有调节作用.

针对目前笼养青脚麻羽肉种公鸡均匀度低下的现状,结合今后青脚麻羽肉种鸡的发展趋势,文章详细讲解了笼养青脚麻羽肉种公鸡在育雏期、育成期、成熟期各阶段的均匀度管理措施.

To investigate the difference on carcass performance and meat quality of quality chicken between cage rearing and free-range rearing,400 male chicks from pure line S07 bred by Sichuan Dahen Poultry Breeding Company were chosen and reared for 5 weeks in cage,divided into cage rearing group and free-range rearing group after 5 weeks age,the two groups were used the same feeding program. The result of slaughter test and meat quality measurement at 10 and 22 weeks age showed that,live weight,carcass weight,percentage of abdominal fat,intramuscular fat(IMF)content and muscle fiber density of cage group were significantly higher than those of free-range group(P<0.01),whole net carcass rate and half net carcass rate were higher than those of free-range group(P<0.05),however,dressing percentage,breast muscle percentage,leg muscle percentage and inosine monophosphate(IMP)content had no significant differences,and IMF and IMP were increasing as days went on, but the deposition rate of IMF was higher than that of IMP in cage group.

<正>(上接第4期第21页)问:怎样修建鸭舍?答:育雏舍:初生雏鸭绒毛短,自身调节体温能力弱,抵抗力差,对外界环境需要逐渐适应,需要人工保温,因此,育雏舍要求保温性能良好,干燥透气。育雏舍因

近年来,我国鸭业迅猛发展,鸭产业的增长速度一度赶超养鸡业,许多农民朋友也通过养鸭致了富,然而,在实际生产当中,仍然存在许多问题,譬如生产消费区域的问题、品种的问题、孵化的问题、饲养管理问题、疾病问题等等,都需要养鸭的朋友关注和应对。从本期开始,我们请四川省畜牧科学研究院的水禽专家以问答的形式介绍养鸭过程中的难点、要点,以供养鸭朋友们借鉴!

本研究选取四川大恒优质肉鸡S01、S05、S06和S05×S01和S06×S015个群体,比较分析2组杂交组合(S05×S01和S06×S01)的外观性状、成活率、孵化率、健雏率以及产肉性能等重要生产性能。结果表明:5个优质肉鸡群体外观性状与地方鸡种一致,成活率、孵化率和健雏率较高,产肉性能良好,适于规模化养殖;杂交组合S05×S01和S06×S01屠宰率都在85%以上,全净膛率在65%以上,产肉性能良好;杂交鸡S06×S01生长速度快,饲料报酬高,适宜对优质肉鸡生长速度要求高的市场推广应用,而杂交鸡S05×S01生长速度较慢,适宜于放养条件下对优质肉鸡生长速度要求不高的市场推广。

历经20余年的我国优质肉鸡育种业,为畜牧业结构调整和家禽产业发展做出了巨大贡献.本文就今后优质肉鸡育种的总体思路、技术经济指标、育种规划、技术手段等方面进行了思考,提出了应注意的问题.

种蛋经机器清洗消毒处理后,与未处理的对照组相比较,入孵蛋孵化率提高了2.68个百分点,受精蛋孵化率提高了1.42个百分点,健雏率提高了0.7个百分点,经统计检验,两者差异极显著(P＜0.01).对照组死胚蛋中大肠杆菌检出率9.09%、沙门氏菌检出率54.55%,处理组大肠杆菌或沙门氏菌检出率均为零.种蛋清洗消毒后能显著提高孵化效果及雏鸡质量.

table eggs from hens of the same age were projected to nine different washing and disinfection procedures based on the combinations of washing water temperature(20℃～25℃,42℃～44℃and50℃～53℃)and disinfection processing time (10,30and50seconds),each procedure with30eggs.Different procedures were judged by the total number of bacteria on the surface of eggshell,which was measured right after washing and disinfection processing.The results suggested that the washing water temperature was42℃～44℃,disinfection time was50seconds.

Three coating aggents,i.e Sodium Silicate(treatment A),Light Oil(treatment B)and Cooking Oil(treatment C),were used to spray coat the washed and disinfected chicken eggs.Eggs only washed and disinfected but not coated(treatment D)and the eggs neither washed and disinfected nor coated (treatment E)were made as controls.Egg quality(Hough unit)was determined at10,20,30,40,50and60days of storage.The results showed that hough unit of eggs with treatments A,B and C were higher than that of treatment D and E,with highest hough unit with treatment B.

The number of bacteria was measured on the surface of different eggshells from chicken farms.The result showed that10percent and70percent chicken eggs contain Salmonella and Escherichia coli on the surface of eggshell.