Evaluation of Immunomodulatory Activity of the Herbals Formula Viranur, Turmeric （Curcuma heyneana Val.） and Phyllanthus （Phyllanthus niruri L.） in Layer Chicken Vaccinated with Avian Influenza

The aim of this research was to know the effect of herbal as immunomodulator on chicken layer vaccinated with avian influenza. A total of 60 chickens were alloted into three treatment groups： control group （KA）, group KB and group KC, with 20 chicken each group. All the chickens were vaccinated with Newcastle disease （ND） in the age of one week, and a week later they were vaccinated with avian influenza （AI）. The chickens in group KB were drunken with herbal solution containing of 5 g turmeric （Curcuma heyneana Val.） and 25 g phyllanthus （Phyllanthus niruri L.） and group KC were drunken with herbal solution containing of 36 g the herbals formula Viranur and 25 g phyllanthus （Phyllanthus niruri L.）, respectively for four weeks. Thirty days after AI vaccinated, all of chicken were weighed and necropsied. Samples from bursa of Fabricius, tymus and spleen were taken for weighing and histopathological examination. The weight indexs of bursa of Fabricius, tymus and spleen were not significantly different between control group and treatment group in the considered statistically significance （P 〉 0.05）, but the treatment groups （KB and KC） had higher weight index. The histopathologically changes of spleen in both control group and treatment groups were not different, although in the group KC, in bursa of Fabricius, there was lymphocyte increase in its lymphoid follicles; and in the group KB and KC, the tymus were more widening in the cortex than medulla. The conclusion of this study showed that the herbals can stimulate lymphocyte activity.

Bacteriological and pathological studies of egg peritonitis in Commercial layer chicken in Namakkal area

Objective:To detect the various bacteriological agents and pathological changes in commercial layer chicken affected with egg yolk peritonitis in Namakkal region of India.Methods:A total of 6572 layer chicken from 85 commercial farms were subjected for the study,out of which 1715 showed various types of oviduct almoimalities.Among the 1715,264 birds from six farms were identified as egg peritonitis on the basis of postmortem examination.Trachea,lung,heart blood,liver,peritoneal exudate,oviduct(infundibulum,magnum,uterus)and cloacal swabs were collected from the 264 birds with egg peritonitis lesion for screening of bacterial agents.Signalment,clinical signs and pathological changes were recorded in the affected flocks.Result:The results of the present investigation indicated that the E.coli associated egg peritonitis was responsible for 15.39%of the reproductive tract abnormalities in commercial layers between 21 and 80 week of age.In the affected flocks egg production drop and mortality varied from 3%to 20%and 0.5%to 7.0%respectively.It was noticed during peak egg production(21 to 60week)and southwest monsoon season(58%).Statistical analysis of age,season and egg production by Chi square test of independence revealed highly significant difference.E.coli was isolated as a pure culture and concurrent with other bacterial agents in 226 and 38 birds respectively.Among the fifteen E.coli serotypes identified serotype O_(166),O_(?)and O_(111)were predominant.Necropsy examination of affected birds revealed the presence of amorphous or insipissiated yolk material in the abdominal cavity with inflammatory changes in the ovary,oviduct and intestine.Microscopically the oviduct surface epithelium showed degeneration and desquamation,moderate to marked infiltration of inflammatory cells especially heterophils and lymphocytes in various regions and lumen contained serofibrinous exudate,inflammatory and desquamated epithelial cells with bacterial microcolonies.Ovarian follicles revealed hyperemia,degeneration of granulosa cells and infiltration of inflammatory cells.Intestine showed degenerative,necrotic and inflammatory lesion.Conclusion:The findings of this study showed that the egg peritonitis might be caused by either the translocation of intestinal E.coli into the peritoneal cavity or by the movement of cloacal E.coli into the oviduct followed by ascension of these bacteria up the oviduct,through the infundibulum,and into the peritoneal cavity.To control the egg peritonitis faecal contamination with E.coli should be minimized.

Identification of recombination hotspots and quantitative trait loci for recombination rate in layer chickens

Background: The frequency of recombination events varies across the genome and between individuals, which may be related to some genomic features. The objective of this study was to assess the frequency of recombination events and to identify QTL(quantitative trait loci) for recombination rate in two purebred layer chicken lines.Methods: A total of 1200 white-egg layers(WL) were genotyped with 580 K SNPs and 5108 brown-egg layers(BL)were genotyped with 42 K SNPs(single nucleotide polymorphisms). Recombination events were identified within half-sib families and both the number of recombination events and the recombination rate was calculated within each0.5 Mb window of the genome. The 10% of windows with the highest recombination rate on each chromosome were considered to be recombination hotspots. A BayesB model was used separately for each line to identify genomic regions associated with the genome-wide number of recombination event per meiosis. Regions that explained more than 0.8% of genetic variance of recombination rate were considered to harbor QTL.Results: Heritability of recombination rate was estimated at 0.17 in WL and 0.16 in BL. On average, 11.3 and 23.2 recombination events were detected per individual across the genome in 1301 and 9292 meioses in the WL and BL,respectively. The estimated recombination rates differed significantly between the lines, which could be due to differences in inbreeding levels, and haplotype structures. Dams had about 5% to 20% higher recombination rates per meiosis than sires in both lines. Recombination rate per 0.5 Mb window had a strong negative correlation with chromosome size and a strong positive correlation with GC content and with CpG island density across the genome in both lines. Different QTL for recombination rate were identified in the two lines. There were 190 and 199 non-overlapping recombination hotspots detected in WL and BL respectively, 28 of which were common to both lines.Conclusions: Differences in the recombination rates, hotspot locations, and QTL regions associated with genomewide recombination were observed between lines, indicating the breed-specific feature of detected recombination events and the control of recombination events is a complex polygenic trait.

Tolerance Study for Standardized <i>Macleaya cordata</i>Extract Added to Chicken Layer Diet

The objective of this study was to assess the effects of Sangrovit?, a standardized preparation of Macleaya cordata extract (MCE), on the health status and egg laying parameters of layer chickens. Layer chickens (N = 360) were randomly divided into four groups (90 birds/treatment, 10 birds/pen) and fed either a standard basal feed (T1) or a basal diet that was supplemented with 100 mg/kg (T2), 500 mg/kg (T3) or 1000 mg/kg (T4) Sangrovit? (providing 0, 3.7, 18.5, and 37.0 mg MCE/kg feed, respectively) for 56 consecutive days. Live Weight (LW), Average Daily Feed Intake (ADFI) and the Feed Conversion Ratios (FCR) were calculated during the study, and biochemical and hematological endpoints were obtained at the end of the study (Day 56). Eggs were analyzed for the isoquinoline alkaloids sanguinarine and chelerythrine. No statistically significant (P > 0.05) differences were found between control and treatment groups for LW, ADFI and FCR. There was a significant increase in the % laying in groups T3 and T4 for the study overall, but no significant differences in egg size during the study. Blood biochemical analyses showed a near-significant trend for decreased bilirubin in the T2 and T4 groups, but this was not dose-dependent and not considered treatment-related. The percent hemoglobin was significantly decreased in the high dose group, but was not considered treatment-related as it was not a dose-dependent effect. No treatment-related changes were found after necropsy of the selected organs. No quantifiable sanguinarine or chelerythrine was found in the eggs after 56 days administration of the MCE preparation to the hens. The results of this study show that consumption of a standardized MCE preparation at up to 1000 mg/kg feed in laying hens had no adverse effect on the hen or eggs, and no residual sanguinarine or chelerythrine was transferred to the eggs.

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.

禽呼肠孤病毒在我国部分地区蛋鸡群中的血清流行率和风险因素分析

禽呼肠孤病毒(ARV)在我国流行范围较广,感染家禽后使其出现病毒性关节炎、生长不良和产蛋量下降等表现,对我国养禽业造成较严重的经济损失。为了解我国蛋鸡群中ARV的流行情况及存在的感染风险因素,本试验在2022年11月—2023年3月从北京、天津、河北、山东、河南、江苏、陕西、湖北和重庆9个省市的45个蛋鸡养殖场(其中包括祖代蛋鸡群、父母代蛋鸡群和商品代蛋鸡群),收集共计45份调查问卷和968份血清样本。采用酶联免疫吸附试验(ELISA)检测血清中的ARV抗体,并结合调查问卷,采用单因素分析和逻辑回归分析方法找到蛋鸡出现ARV感染症状的风险因素。ELISA检测结果显示,968份血清样本中检出阳性863份,阳性率为89.15%(95%CI:87.0%~91.0%);单因素分析结果显示,全进全出饲养模式下的蛋鸡出现ARV感染症状的概率显著低于区域性全进全出饲养模式或不同日龄、不同批次混养饲养模式下的蛋鸡,且具有较强程度的关联(P<0.05,0.1<OR<0.3);生物安全防控严格的大、中型规模化养殖场(5万只以上)的蛋鸡出现ARV感染症状的概率显著低于生物安全防控存在不足的小型养殖场(2万~5万只)的蛋鸡,且具有较强程度的关联(P<0.05,0.1<OR<0.3);员工不注意对鸡舍消毒的养殖场饲养的蛋鸡出现ARV感染症状的概率显著高于员工对鸡舍具有较强或一般消毒意识的养殖场饲养的蛋鸡,具有中等程度的关联(P<0.05,1.5<OR<3.0)。综上所述,饲养模式、养殖场规模和员工对鸡舍的消毒意识可能是产蛋鸡群感染ARV的风险因素。

Pathology and molecular characterization of recent Leucocytozoon caulleryi cases in layer flocks

Leucocytozoonosis was found in three layer farms in chickens with suspected fatty liver or fatty liver hemorrhagic syndrome in Korea between 2009 and 2011.These layer chicken flocks showed both mortality and decreased egg production for one or two weeks when they were between 59 and 82 weeks old.At the necropsy,the most prominent gross lesions were found in the liver,which was enlarged,had a fragile texture,exhibited yellowish discolorations,and had various hemorrhagic lesions.Tissue reactions associated with megaloschizonts specific for Leucocytozoon caulleryi were prominent upon microscopic examination of the liver without significant lipidosis.In addition,the ovaries and uterus were the most affected organs for Leucocytozoon caulleryi multiplication,which led to decreased egg productions.Molecular studies with formalin-fixed,paraffin-embedded tissues were performed in search of a partial region of the cytochrome b gene for hemosporidian parasites.Based on these results,the causal agent was determined to be closely related to Leucocytozoon caulleryi reported in Japan and Malaysia.In this study,we describe recently re-occurring leucocytozoonosis in layer chickens,which required histopathology for disease diagnosis.To prevent outbreaks and maintain chicken health and egg production,layer chickens need to be monitored for symptoms of leucocytozoonosis.

水飞蓟素缓解敌草快对蛋雏鸡生长性能、肝重和肝脏抗氧化能力的影响

试验旨在研究水飞蓟素缓解敌草快(DQ)对蛋雏鸡生长性能、肝重和肝脏抗氧化能力的影响。试验选取1日龄海兰白蛋鸡240羽,随机分成4组,对照组(C组)与敌草快组(D组)饲喂基础饲粮,水飞蓟素组(S组)和水飞蓟素+敌草快组(SD组)在基础饲粮中添加1 g/kg水飞蓟素;试验第20天,C组和S组蛋鸡腹腔注射1 mL/kg生理盐水,D组和SD组蛋鸡腹腔注射1 mL/kg DQ溶液。试验期21 d。结果显示:①在1~20日龄时,S组和SD组的平均日增重显著高于C组和D组(P<0.05)。20~21日龄时,与C组相比,S组平均日增重和体重变化率显著升高(P<0.05);与D组相比,SD组的末重、平均日增重和体重变化率显著升高(P<0.05)。②与D组相比,S组绝对肝重和相对肝重显著降低(P<0.05),SD组的相对肝重显著降低(P<0.05)。③与C组相比,S组鸡肝脏总抗氧化能力(T-AOC)和超氧化物歧化酶(SOD)活性显著升高(P<0.05);与D组相比,SD组鸡肝脏T-AOC显著升高(P<0.05),丙二醛(MDA)含量显著降低(P<0.05)。说明饲粮中添加水飞蓟素可改善DQ诱导的氧化应激蛋雏鸡的生长性能、肝重和肝脏抗氧化能力。

育雏期蛋鸡玉米氨基酸标准回肠消化率的测定及预测方程的建立

本试验旨在分析不同产地玉米的理化特性及育雏期蛋鸡对其氨基酸的表观回肠消化率(AID)和标准回肠消化率(SID),并基于物理特性和化学成分含量建立育雏期蛋鸡玉米氨基酸SID的预测方程。试验选取528只31日龄健康且体重[(284±10)g]相近的京红1号蛋雏鸡,随机分为11个组,每组6个重复,每个重复8只鸡。C0组饲喂无氮饲粮,C1~C10组饲喂不同产地玉米配制的半纯合试验饲粮,无氮饲粮和试验饲粮中均添加0.50%的二氧化钛(TiO_(2))作为外源指示剂,试验周期为3 d。试验结束后,使用二氧化碳(CO_(2))气体致晕并宰杀所有鸡只,采集回肠末端食糜测定氨基酸和TiO_(2)含量并计算氨基酸SID。结果表明:1)在风干基础下,10种玉米总能(GE)平均值为19.29 MJ/kg(18.03~23.81 MJ/kg),干物质(DM)、粗蛋白质(CP)、粗脂肪(EE)、粗灰分(Ash)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)、总磷(TP)、钙(Ca)和总淀粉(TS)含量平均值分别为86.95%(84.45%~89.24%)、7.96%(6.89%~9.52%)、3.43%(2.03%~4.50%)、1.26%(1.00%~1.58%)、8.12%(7.50%~9.52%)、2.40%(1.86%~3.66%)、0.26%(0.18%~0.31%)、0.05%(0.01%~0.13%)和65.93%(56.75%~70.64%),容重平均值为756.47 g/L(695.19~799.18 g/L),千粒容积平均值为446.40 mL/千粒(364.00~504.00 mL/千粒),千粒重平均值为337.90 g/千粒(250.15~381.55 g/千粒);玉米中必需氨基酸含量平均值为蛋氨酸0.16%(0.10%~0.21%)、赖氨酸0.25%(0.22%~0.32%)、苏氨酸0.31%(0.26%~0.40%)、色氨酸0.06%(0.05%~0.08%)。2)育雏期蛋鸡对玉米氨基酸SID为蛋氨酸92.35%、赖氨酸87.85%、苏氨酸82.86%、色氨酸83.98%。3)育雏期蛋鸡对玉米中17种氨基酸的SID预测方程的决定系数(R^(2))在0.663~0.965,其中丝氨酸SID预测方程的拟合度最高(SID=79.130+0.541GE+7.144Ash-2.767NDF+49.646甘氨酸,R^(2)=0.965,P<0.01),且苯丙氨酸、缬氨酸和半胱氨酸SID预测方程的R^(2)均超过0.90,拟合度好。综上所述,不同产地玉米的物理特性和化学成分变异较大,这是造成育雏期蛋鸡对不同产地玉米氨基酸AID和SID差异大的主要原因,其中玉米GE和CP、EE、ADF、NDF、TS及部分氨基酸含量可作为育雏期蛋鸡对玉米氨基酸SID预测的关键因子。

贵州省蛋鸡养殖机械化水平发展研究

农业机械化是农业现代化的基础工程和重要标志。本文以蛋鸡养殖为例,对养殖分环节(饲料收获、饲喂、粪污处理、环境控制、集蛋)提出了蛋鸡养殖机械化水平指标体系,给出了计算方法。以贵州省426个蛋鸡养殖场采样的数据对机械化水平进行计算,对蛋鸡养殖各环节的机械化生产短板进行剖析,提出了提升薄弱环节机械化水平的建议。

一种中药复合物对蛋鸡产蛋性能和免疫功能的影响

文章旨在研究日粮中添加不同浓度的中药复合物对蛋鸡生产性能、免疫功能和蛋品质的影响。试验选取400只健康状态良好,体重及生产性能相近的27周龄罗曼褐蛋鸡。将其随机分成4个处理组,每组5个重复,每个重复20只。对照组饲喂不添加任何中药复合物的基础日粮,3个试验组中分别饲喂在基础日粮中添加1%、2%、3%的中药复合物的试验日粮。试验期共42天。结果显示,在日粮中添加1%的中药复合物能够提高蛋鸡的生产性能,改善鸡蛋的蛋品质,增强机体的免疫功能。

饲料营养水平及形态对0-60日龄蛋雏鸡生长性能的影响

为探索不同营养水平的颗粒破碎料和粉料对0~60日龄蛋雏鸡生长性能的影响,试验选用健康、体重相近的0日龄京红1号商品代蛋雏鸡3600只,随机分成3个处理组,每组1200只,每组3个重复,每个重复400只。试验期0~60日龄,试验分3段进行,0~14日龄3个处理组饲喂同一种颗粒破碎料;15~35日龄和36~60日龄,对照组饲喂高营养浓度粉料(代谢能水平分别为12.10 MJ/kg和11.93 MJ/kg,粗蛋白质水平分别为19.5%和17.5%),试验T2组饲喂中营养浓度粉料(代谢能水平分别为12.10 MJ/kg和11.85 MJ/kg,粗蛋白质水平分别为19.0%和17.0%),试验T3组饲喂低营养浓度颗粒破碎料(代谢能水平分别为12.10 MJ/kg和11.68 MJ/kg,粗蛋白质水平分别为18.5%和16.5%)。结果表明:28、35、42、56、60日龄体重,试验T3组显著高于试验T2组(P<0.05),28、35、42、49日龄胫长,试验T3组显著高于对照组(P<0.05)。0~35日龄增重,试验T3组较对照组、试验T2组分别高13.2、17.5 g,料重比显著低于对照组、试验T2组(P<0.05);36~60日龄增重,对照组显著高于试验T2组,高31.8 g(P<0.05),料重比对照组<试验T3组<试验T2组,差异显著(P<0.05),每400 g增重的饲料成本对照组显著低于试验T2组、试验T3组,分别低0.39、0.26元(P<0.05)。综合生长性能和经济效益分析,在本试验营养水平条件下,推荐蛋雏鸡颗粒破碎料饲喂至35日龄(15~35日龄日粮代谢能水平12.10 MJ/kg,粗蛋白质水平18.5%),36~60日龄饲喂粉料(日粮代谢能水平11.93 MJ/kg,粗蛋白质水平17.5%)。

重组禽流感三价灭活疫苗免疫商品肉鸡和蛋鸡效果的研究

研究旨在评价重组禽流感三价灭活疫苗在临床中的效果。将40 000只三黄肉鸡分为A组、B组、C组,A组20 000只,B组19 900只,C组100只。A组与B组分别免疫疫苗A与疫苗B,C组为不免疫对照组。2周龄首免,颈部皮下注射,0.3 mL/羽份。6周龄进行二免,颈部皮下注射,0.5 mL/羽份。20 000只蛋鸡分为D组、E组、F组,D组10 000只,E组9 900只,F组100只。D组与E组分别免疫疫苗A与疫苗B,F组为不免疫对照组。2周龄首免颈部皮下注射,0.3 mL/羽份。6周龄进行二免,颈部皮下注射,0.5 mL/羽份。13周龄进行三免,颈部皮下注射,0.5 mL/羽份。免疫后进行安全性评价,并于不同时间监测抗体水平。结果显示,免疫后14 d,各组三黄肉鸡和蛋鸡均未出现副反应,且2~3次免疫后,疫苗基本吸收完全。免疫效力试验结果显示,三黄鸡首免2周后HI抗体即可达到5.0以上,3周后可达到完全保护水平;蛋鸡在产蛋高峰前可达到7.5 log2以上,2~3次免疫后抗体即可达到峰值9~10 log2。研究表明,不同厂家疫苗免疫后抗体均可产生100%保护,但抗体水平略有差异。

商品蛋鸡成髓细胞瘤、血管瘤型J亚群白血病病理学初报

2007年7月,山东某鸡场8 000余只150日龄海兰褐鸡发病,病鸡特征性表现衰竭、消瘦和血管瘤。大体病变:内脏器官肿大,表面及切面可见大小不等的灰白色结节;血管瘤大小不等、富有弹性,内含大量血液,血液内富含成髓细胞;组织学病变:肝脏、脾脏、骨髓、肠管和胰腺浆膜面有大量的胞质含嗜碱性颗粒的成髓细胞增生,同时在肠管固有层出现明显的肠腺上皮细胞和网状细胞增生,腺胃固有层出现明显的网状细胞增生,血管瘤为典型的海绵状血管瘤,可见其发展的各个阶段;免疫组织化学检测:经REV与ALV-J单克隆抗体检测发现,REV抗原阴性,而ALV-J抗原强阳性。在骨髓、肝脏及其它组织内的成髓细胞内、血管瘤海绵状壁层内皮细胞、增生的肠腺上皮细胞、腺胃腺小管上皮细胞、网状细胞内及部分间质内可见强阳性信号。因此,此病为成髓细胞瘤、血管瘤型并伴发多种肿瘤的J亚群白血病,这在国内外尚未见报道。

女贞子对蛋鸡育成期生长发育和免疫功能的影响

本研究旨在观察女贞子对蛋雏鸡生产性能和免疫功能的影响。试验选用1日龄海兰褐蛋雏鸡384只,随机分为4组,每组设6个重复。结果表明,女贞子对蛋鸡日增重、饲料转化率无显著影响;饲料中添加0.5%女贞子能显著提高雏鸡生长前期的法氏囊指数,添加1%的女贞子能提高雏鸡生长中、后期的胸腺与脾脏指数;女贞子能显著提高蛋雏鸡的新城疫抗体效价;女贞子对雏鸡生长前、中期的C3含量和生长中期的TNF含量有提高作用;女贞子能显著提高鸡外周淋巴细胞转化率。说明女贞子对蛋鸡育成期的生长发育和免疫功能有积极作用。

蛋鸡中发现J亚群白血病与网状内皮增生症自然混合感染

发病蛋鸡经组织学、免疫组化检测确诊为J亚群白血病与网状内皮增生症混合感染。与人工接种病例不同的是,在肿瘤组织内还发现一种特殊的细胞——淋巴-巨噬细胞;在骨髓和肿瘤组织中检测到部分髓细胞胞浆内有ALV-J抗原表达。从发病情况、各器官病变程度及免疫组化结果来看,2种病原存在明显的相互协同作用,脾可能是网状内皮增生症的原发器官,但其发病的时间可能不如J亚群白血病早。此次在蛋种鸡发现此混合感染提示,病毒在环境选择压及免疫选择压的作用下,其生物特性、致病作用以及宿主范围均可发生改变,应警惕J亚群白血病和网状内皮增生症混合感染在蛋鸡中的大面积暴发。

商品蛋鸡成髓细胞瘤、血管瘤型J亚群白血病病毒特性的研究

2007年7月山东某蛋鸡场150日龄海兰褐蛋鸡发病，前期经病理学和免疫组织化学检测证明和ALV—J密切相关。取4只病鸡的肝组织处理后接种鸡胚成纤维细胞（CEF）培养，用ALV—J单抗G2-3进行间接免疫荧光检测，结果呈现强阳性，将反应为阳性的4株病毒分别命名为WS0701、WS0702、WS0703和WS0704；根据ALV-J原型株HPRS-103的序列设计1对针对外源性ALV—J的引物P1和P2，提取阳性CEF基因组DNA作为模板，PCR扩增后，得到长度为924bp的片段；PCR扩增产物测序结果显示，与HPRS-103的同源性为95．0％～97．5％，与国内分离株的同源性为92．0％～95．9％；遗传变异分析结果表明成髓细胞瘤型、血管瘤型ALV-J与国内毒株的同源性较远，而与HPRS-103的同源性最近，这说明ALV—J在蛋鸡体内复制的过程中有返祖现象，并呈现了新的肿瘤学特征。

我国部分地区蛋鸡群鸭源鸡杆菌血清流行病学调查

为了解鸭源鸡杆菌(Gallibacterium anatis)在我国部分地区鸡群中的感染状况,本实验采用G.anatis微量凝集试验对我国河南、山东和山西等不同地区的1 314份鸡血清样品进行了G.anatis感染的血清流行病学调查,对G.anatis的感染率、感染品种、日龄等进行分析。结果表明:我国河南、山东和山西等地鸡群均存在G.anatis感染,其中G.anatis血清Ⅰ型抗体阳性率为11.95%,G.anatis血清Ⅱ型抗体阳性率为23.29%,G.anatis血清Ⅳ型抗体阳性率为9.82%。不同省份的鸡群感染G.anatis的血清阳性率存在一定差异,河南、山东和山西的血清阳性率分别为23.12%、25.27%和52.94%。对河南地区不同品种和日龄鸡的调查表明,均存在不同程度的感染,但血清阳性率有显著差异,表现为罗曼鸡的血清阳性率比海兰鸡高,开产前蛋鸡的血清阳性率低于开产后的血清阳性率。

复合益生菌对蛋鸡消化道微生物区系的影响

为探讨微生态制剂对蛋鸡消化道微生物区系的影响,利用致病性大肠杆菌对产蛋后期的矮小型固始鸡进行攻毒试验。结果表明,试验组蛋鸡的腹泻率明显降低,其胃、小肠、大肠、盲肠内的大肠杆菌数量也比对照组均有所降低(P>0.05),说明微生态制剂对鸡有很好的抑菌保护作用。另外,该复合益生菌可明显地提高鸡胃中乳酸菌的数量(P<0.05),而对肠道中乳酸菌的影响不明显。

商品蛋鸡J亚群禽白血病病毒分离鉴定及序列分析

为了解商品蛋鸡群中J亚群禽白血病病毒(ALV-J)流行情况和病毒特性,本实验对感染血管瘤与髓细胞瘤混合型ALV-J的商品海兰褐蛋鸡进行了病毒分离,对2个分离株的致瘤关键基因序列LTR与gp85进行了测定,并与参考毒株进行比对,分析结果表明这两株病毒的LTR及gp85均存在显著的变异。在这两个基因的遗传进化树中均形成一个单独的分支:LTR的U3序列与参考毒株的同源性低至89.7%～92.4%,而参考毒株之间的同源性高达90.7%～99.6%,这两株病毒的U3区变异产生了一个与肿瘤形成与转移间接相关的调控元件TCF11(Transcription Factor11),但Y box、TATA box、CArG box都很保守;两株病毒的gp85氨基酸序列均在第179位缺失一个Lys,两个毒株的gp85蛋白序列与肉鸡分离毒株之间的同源性很低,为86%～89%,而与参考蛋鸡分离毒同源性相对较近,为89.2%。本研究证实从多种肿瘤类型并发的蛋鸡自然发病病例中分离到ALV-J病毒,其关键序列发生了显著的变异。