饲养方式和饲喂水平对鸡肉硫胺素含量及肉质的影响

本文研究了不同饲养方式和饲喂水平对“广西黄”黄羽肉鸡肉质的影响，结果表明，放养(饲喂水平为对照组的50％)肉鸡的肌纤维直径显著增大，密度减小，肌肉脂肪含量明显升高。肌肉肌苷酸、硫胺素含量亦显著升高。     

大豆酶解蛋白对肉鸡生产性能、肉品质、肠道和免疫器官发育的影响

试验旨在研究日粮中添加不同剂量大豆酶解蛋白(ESM)对肉鸡生产性能、肉品质、肠道发育和免疫机能的影响,筛选出肉鸡日粮中适宜的ESM添加水平。选取1日龄健康AA肉鸡432只,随机分为4组(1个对照组和3个试验组),每组6个重复,每个重复18只。对照组饲喂基础日粮,试验组饲喂在基础日粮中分别添加ESM含量为0.3%、0.6%、0.9%的试验日粮,饲养期42 d。结果显示,随着ESM的添加,肉鸡0~42日龄的采食量和料肉比呈现显著降低的一次线性关系(P0.05);肌肉p H和胸肌率分别呈现显著升高和降低的一次线性关系(P0.05);肌肉失水率呈现先降低后升高的二次曲线关系(P0.05);42日龄胸腺和法氏囊指数呈现先升高后降低的二次曲线关系(P0.05);21和42日龄肉鸡的溶菌酶呈现先升高后降低的二次曲线关系(P0.05)。由此可见,添加ESM能够提高肉鸡生产性能和肉品质,并改善其肠道发育和免疫机能,且在添加水平为0.6%时效果最佳。     

饲粮磷水平对肉鸡肉质和脂质代谢的影响

为了分析饲粮磷水平对肉质和脂质代谢的影响,试验选用100只1日龄的肉鸡开展了42天的饲养试验(磷缺乏组、正常组、高磷水平1组和高磷水平2组)。研究结果表明:与正常磷水平组相比,磷缺乏组和高磷组肉鸡的肉品质均降低了。高磷饲粮导致胸肌肌肉亮度值、红度值和剪切力极显著增加、脂肪酸和肌内脂肪含量极显著降低(P0.01)。与正常磷水平组相比,低磷、高磷水平组的苹果酸酶活性显著降低,脂肪合成酶和腺苷酸活化蛋白激酶活性显著升高(P0.05)。与其它处理组相比,正常磷水平饲喂组肉鸡血清中胆固醇和三酰甘油含量最低(P0.05)。高磷饲粮极显著降低了肝脏中脂质的沉积(P0.01),但是能极显著增加胸肌中的磷含量(P0.01)。由此可见,磷缺乏或过量均会影响肉鸡的肉质和脂质代谢。     

枯草芽孢杆菌对肉鸡生长性能、屠宰性能、肉品质、免疫功能、抗氧化功能和肠道形态的影响

试验旨在研究枯草芽孢杆菌对肉鸡生长性能、屠宰性能、肉品质、免疫功能、抗氧化功能和肠道形态的影响。将120只白羽肉鸡随机分成4组,每组3个重复,每个重复10只鸡。对照组肉鸡饲喂基础日粮,Ⅰ组、Ⅱ组、Ⅲ组分别在基础日粮中添加100、200、400 mg/kg枯草芽孢杆菌。试验期42 d。结果显示,与对照组相比,22～42日龄、1～42日龄时,各试验组肉鸡的平均日增重均显著升高（P<0.05）,Ⅱ组、Ⅲ组肉鸡末重均显著升高（P<0.05）,Ⅱ组肉鸡的料重比显著降低（P<0.05）。与对照组相比,Ⅱ组、Ⅲ组肉鸡半净膛率、滴水损失率、烹煮损失率均显著升高（P<0.05）;Ⅱ组肉鸡屠宰率、胸肌率及肌肉pH值均显著升高（P<0.05）。Ⅱ组肉鸡脾脏指数显著高于对照组（P<0.05）。与对照组相比,各试验组肉鸡血清免疫球蛋白G (IgG)含量均显著升高（P<0.05）,尿素氮（BUN）含量显著降低（P<0.05）;Ⅱ组、Ⅲ组肉鸡血清免疫球蛋白A (IgA)、总蛋白（TP）、丙二醛（MDA）含量均显著高于对照组（P<0.05）。Ⅱ组肉鸡血清谷丙转氨酶...     

甜菜碱对肉鸡生长性能、脂质代谢及肌肉风味品质的影响

本试验旨在研究饲粮中添加不同水平的甜菜碱对肉鸡生长性能、脂质代谢及肌肉风味品质的影响。选用1日龄爱拔益加(AA)健康肉公鸡240只,随机分为4组,每组6个重复,每重复10只。对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮中添加0.05%、0.10%和0.20%甜菜碱的试验饲粮。试验全期42 d,前期为第1~21天,后期为第22~42天。结果表明:与对照组相比,0.20%甜菜碱能够显著提高肉鸡前、后、全期平均日增重和前、后期体重(P0.05),显著降低全期料重比(P0.05)。与对照组相比,饲粮中添加甜菜碱显著提高了肉鸡胸肌中肌苷酸含量及胸肌和腿肌中肌肉脂肪、风味氨基酸和总游离氨基酸含量(P0.05)。与对照组相比,0.20%甜菜碱能够显著增加肉鸡胸肌和腿肌饱和脂肪酸、不饱和脂肪酸、单不饱和脂肪酸含量,以及胸肌多不饱和脂肪酸含量和不饱和脂肪酸/饱和脂肪酸(P0.05)。与对照组相比,0.20%甜菜碱显著降低血清中甘油三酯、总胆固醇和脂联素含量(P0.05),显著提高血清中高密度脂蛋白、瘦素和胰岛素含量(P0.05)。由此可见,肉鸡饲粮中添加甜菜碱可以提高肉鸡的生长性能,促进脂质代谢,改善肌肉风味品质,以0.20%添加效果为最佳。     

香蕉加工残渣对肉鸡生长性能、养分消化、肉品质及经济效益的影响

文章旨在评估日粮添加不同水平的香蕉加工残渣对肉鸡生长性能、养分消化、肉品质及经济效益的影响。试验将平均体重一致的540只1日龄肉鸡随机分为3组,每组5个重复,每个重复36只,在整个1～42 d的试验期,对照组肉鸡饲喂基础日粮（香蕉加工残渣水平为0%）,T1和T2组肉鸡饲喂香蕉加工残渣添加水平分别为10%和20%的日粮。结果：10%香蕉加工残渣组肉鸡42 d体重较对照组显著提高3.59%（P＜0.05）,但1～42 d料重比显著降低3.28%（P＜0.05）。与对照组相比,10%和20%香蕉加工残渣组22～42 d肉鸡的平均日增重分别显著提高5.25%和3.28%（P＜0.05）,而22～42 d肉鸡的料重比分别显著降低4.82%和3.01%（P＜0.05）。与对照组相比,10%和20%香蕉残渣组肉鸡有机物表观消化率显著提高3.81%和4.19%（P＜0.05）,同时10%香蕉残渣组肉鸡粗蛋白质表观消化率显著提高3.40%（P＜0.05）。与对照组相比,10%和20%香蕉加工残渣组肌肉硫代巴比妥酸反应物浓度显著降低（P＜0.05）,肌肉系水力和蛋白硫醇含量显著升高（P＜0.05）。经济效益分析结果显示,10%香蕉加工残渣组肉鸡单公斤的增重成本较对照组显著降低5.08%（P＜0.05）。结论：日粮添加香蕉加工残渣提高了肉鸡生长后期的日增重和饲料效率,同时改善了有机物表观消化率及肌肉系水力,综合考虑生产饲料成本,1～42 d肉鸡日粮中香蕉加工残渣适宜的添加水平为10%。 [关键词]香蕉残渣|肉鸡|生长性能|养分消化|肉品质|经济效益     

降脂添加剂对肉鸡胆固醇代谢的影响

用4周龄艾维茵肉仔鸡随机分为4组，每组32只，4个（笼）重复，分别在基础日粮中加入0，0.03%,0.06%,0.10%含胆固醇合成抑制剂（Lovastatin）的添加剂饲喂三周。研究Lovastatin对肉鸡血浆、肌肉、肝脏中胆固醇和甘油三脂含量的影响。结果表明，试验组肉仔鸡的血浆总胆固醇（TC）和低密度脂蛋白胆固醇（LDL－Chol）的水平均显著低于对照组（P＜0.01），血浆总甘油三脂（TG）随添加量增加显著提高（P＜0.05），高密度脂蛋白胆固醇含量下降（P＞0.05）。试验组肉鸡中总胆固醇（TC）和总甘油三脂（TC）含量均显著低于对照组（P＜0.01），而肝脏中各指标差不显著（P＞0.05）。与对照组相比，试验组饲料利用率提高（P＞0.05），生长速度相似。屠宰率、腹脂率、胸肌率、腿肌率略高于对照组，差异不显著（P＞0.05）。胆固醇合成抑制剂能够减少肉鸡肌肉、肝脏胆固醇的沉积，改善肉鸡生产性能。     

有效温度与日粮能量水平对肉鸡生产性能及胴体组成的影响

采用4×3双因子多水平随机试验设计,研究了有效环境温度(ET,15.0、21.2、35.3和37.6℃)和日粮能量浓度(ME,11.71、12.55和13.39 MJ/kg)对4～6周龄肉鸡生产性能、屠体性能和肌肉成分的影响.试验选用21日龄AA肉鸡216只,随机分为12个组,置于4个环控舱中,每舱3组,每组等分成3个重复 (笼),每个重复(笼)6只鸡,饲喂1种试验日粮,为期3周.试验开始及结束时测量试鸡的个体体重和相应阶段各重复的耗料量;饲养试验结束时进行屠宰,测量屠宰指标,并取胸、腿肌测定其成分.结果表明(1)有效温度对肉鸡的日采食量、日增重及料肉比影响显著(P＜0.05),当温度超过常温时,日采食量及日增重显著下降(P＜0.05),料肉比显著升高(P＜0.05);(2)高温或极端高温显著提高肉鸡的屠宰率、半净膛率、全净膛率和腿肌率(P＜0.05),显著降低屠体重、胸肌重、腿肌重、胸肌率、皮下脂肪厚、肌间脂肪宽(P＜0.05).低温组屠宰率显著升高(P＜0.05),皮下脂肪厚显著下降(P＜0.05).随着日粮能量浓度的升高,肉鸡屠体重显著升高(P＜0.05),胸肌率及皮下脂肪厚显著降低(P＜0.05);(3)有效温度对胸肌常规成分和胆固醇含量均有显著影响(P＜0.05).与常温组相比,极高温组鸡的胸肌和腿肌蛋白质含量显著下降(P＜0.05);有效温度的上升与下降都显著增加了胸肌及腿肌的粗脂肪含量(P＜0.05);高温及极高温显著增加了胸肌的水分含量(P＜0.05);低温显著降低腿肌的粗灰分(P＜0.05).日粮能量水平对腿肌粗蛋白含量有显著影响(P＜0.05),与适能组相比,高能组腿肌蛋白质含量显著降低(P＜0.05).有效温度与日粮能量蛋白水平对胸肌粗灰分含量有交互作用(P＜0.05).由此可得,有效温度对肉鸡生产性能、屠体组成和胸肌、腿肌成分的影响程度远远超过日粮能量浓度,高温能显著降低肉鸡生产性能、屠体性能、肌肉蛋白质含量,增加肌肉脂肪含量,而提高日粮能量浓度则可增加肉鸡屠体重,但能否通过调整日粮能量浓度以减缓高温对肉鸡生产性能、其它屠体指标和肌肉成分的影响还有待进一步研究.     

丙酸铬对常规饲养肉鸡生长性能、血清脂代谢、胴体品质及免疫功能的影响

本试验旨在研究饲粮中添加不同水平丙酸铬(CrPro)对常规饲养条件下饲养21 d的肉雏鸡生长性能、血清脂代谢、胴体品质及免疫功能的影响。试验选用体重均一的1日龄科宝500雄性雏鸡252只,随机分为6个组,每组7个重复,每个重复6只鸡。对照组饲喂玉米-豆粕型基础饲粮(含铬0.62 mg/kg),试验组分别饲喂在基础饲粮中添加0.2、0.4、0.8、1.6和3.2 mg/kg CrPro(以铬计)的饲粮。试验鸡只自由采食和饮水,试验期21 d。结果表明:1)饲粮中添加不同水平的CrPro对肉鸡生长性能无显著影响(P0.05)。2)饲粮中添加不同水平的CrPro对血清总胆固醇、甘油三酯和高密度脂蛋白胆固醇含量无显著影响(P0.05),但血清低密度脂蛋白胆固醇(LDLC)含量随饲粮中CrPro添加水平的上升而线性升高(P0.05)。3)饲粮中添加不同水平的CrPro对肉鸡胴体性能和胸肌肉品质均无显著影响(P0.05)。4)肉鸡血清免疫球蛋白A(IgA)和免疫球蛋白G(IgG)含量随饲粮CrPro添加水平的提高呈二次曲线变化(P0.05),并且均在0.4 mg/kg添加组达到最大值; CrPro添加水平有影响肉鸡血清免疫球蛋白M(IgM)含量的趋势(P=0.057 4),且其随着饲粮CrPro添加水平的提高呈二次曲线变化(P0.05)。5)饲粮中添加不同水平的CrPro对21日龄肉鸡免疫器官指数无显著影响(P0.05)。由此可知,饲粮添加CrPro对常规饲养条件下饲养21 d肉鸡的生长性能、胴体性能及肉品质无显著影响,但随饲粮CrPro添加水平的升高,肉鸡血清IgA、IgG及IgM含量均呈现二次曲线变化,且在CrPro添加水平为0.4 mg/kg时达到最大值;饲粮添加CrPro线性提高了常规饲养条件下饲养21 d肉鸡血清LDLC含量。     

添加葛藤草粉饲喂肉鸡效果评价

试验旨在研究饲粮中添加葛藤（Pueraria lobata）草粉对K9肉鸡生长性能、免疫器官指数、肌肉营养成分以及血清生化指标的影响,为开发新的饲料资源、科学利用葛藤提供参考依据。试验选取健康状况良好、体重相近的30日龄K9肉鸡120羽,随机分为3组（每组4个重复,每个重复10羽）,对照组饲喂100%基础饲粮,试验组用葛藤草粉分别替代5%和7%的基础饲粮,试验期60 d。结果表明：(1)添加葛藤草粉对肉鸡的生长性能无显著影响（P>0.05）。(2)添加5%葛藤草粉可显著提高肉鸡法氏囊指数,添加7%葛藤草粉可显著提高肉鸡胸腺指数（P<0.05）。(3)添加5%葛藤草粉可显著提高肉鸡肌肉中干物质含量,添加7%葛藤草粉可显著提高肉鸡肌肉中粗蛋白和肌苷酸含量（P<0.05）。(4)添加5%葛藤草粉能显著提高肉鸡总蛋白含量（P<0.05）。综上所述,饲粮中添加葛藤草粉能在一定程度上增强肉鸡的免疫机能,提升肉质营养风味,改善机体健康状况。结合优劣解距离法（TOPSIS法）综合评价结果可知,葛藤草粉的添加比例为7%时,肉鸡的饲喂效果较好。     

Increased broiler muscle carnosine and anserine following histidine supplementation of commercial broiler feed concentrate

Abstract

A feeding experiment involving histidine supplementation to broiler feed resulted in increased concentration of the histidine containing dipeptides anserine and carnosine in broiler breast muscle. Supplementation with 1 g histidine per kg feed gave a 64% increase in carnosine, and about 10% increase in anserine in the muscle. The standard broiler feed concentrate now in use in Norway seems to contain less histidine than what may be needed for optimal synthesis of carnosine and anserine. These dipeptides have important roles as antioxidants, pH buffering agents and anti-glycation agents. They may have important roles in meat for increasing its stability, shelf life and antioxidant capacity, and it might be speculated that broiler meat rich in anserine and carnosine in the future will be considered a type of functional food, having possible health-beneficial effects. Histidine supplementation of standard Norwegian broiler feed concentrate should be considered.     

Dietary mannanase‐hydrolyzed copra meal improves growth and increases muscle weights in growing broiler chickens

The utilization of copra meal as a feed ingredient is limited because it contains a high level of mannan. However, recent findings indicate that the effect of copra meal on growth performance in broiler chickens can be improved by the supplementation of mannanase in the diet. In the present study, we examined the effect of mannanase‐hydrolyzed copra meal (MCM) on growth performance and muscle protein metabolism in growing broiler chickens (Gallus gallus domesticus). Forty 8‐day‐old male broiler chicks were assigned to two groups (four birds in each pen, five replicates) and fed either a commercial diet (as a control diet) or a diet containing MCM at 0.2% until 22 days of age. Dietary MCM significantly increased the weights of body, breast muscle, and thighs in chickens, whereas the weights of abdominal adipose tissue and liver were not affected. Cumulative feed intake was significantly increased by MCM. Dietary MCM significantly decreased plasma 3‐methylhistidine level. The messenger RNA and protein levels of muscle protein metabolism‐related factors were not altered by MCM. These findings suggest that the growth‐promoting effect of MCM is related to the suppression of muscle proteolysis in growing broiler chickens.     

肉鸡腹水综合征患鸡右心组织钙含量的研究

利用原子吸收分光光度法和焦锑酸钾组化电镜技术,测定肉鸡右心室壁总钙和右心室组织细胞内游离Ca2+含量和分布。结果显示肉鸡腹水综合征患鸡右心室壁总钙含量为(71.2±6.5)mg/kg,显著高于低温未发病和健康肉鸡(分别为58.0±4.4,46.8±3.1,P<0.01)。电镜观察发现Ca2+沉淀颗粒主要散在分布于患鸡心肌胞浆、肌浆网、线粒体等部位,腹水综合征患鸡Ca2+颗粒的沉积量比健康肉鸡显著增多。结果提示心肌细胞内Ca2+的异常可能与肉鸡腹水综合征的发生发展有关。     

5-羟色胺对肉鸡肺动脉平滑肌细胞增殖和凋亡的影响

采用胶原酶消化法培养原代肉鸡肺动脉平滑肌细胞（PASMC）,检测不同浓度的5-羟色胺（5-HT）对肉鸡PASMC增殖的影响,并用流式细胞仪检测PASMC周期和凋亡情况。结果发现,10-4～10-7 mol/L的5-HT能剂量依赖性地促进肉鸡PASMC的增殖,可能是5-HT加速细胞从G1期向S期过渡,同时5-HT也可促进PASMC凋亡,因此在总体上5-HT促进PASMC增殖的作用更明显。     

氟西汀和5-羟色胺对肉鸡肺动脉平滑肌细胞增殖与凋亡的影响

为探讨5-羟色胺转载体(5-HTT)在肉鸡肺动脉高压综合征发病中的机制,采用MTT比色法、流式细胞术及Hoechst33258荧光染色法研究5-羟色胺(5-HT)和5-HTT抑制剂氟西汀对体外培养的肉鸡肺动脉平滑肌细胞(PASMC)增殖与凋亡的影响,发现氟西汀能够抑制5-HT促PASMC增殖的作用;氟西汀能明显促进PASMC的凋亡,但氟西汀和5-HT共同作用于细胞,PASMC凋亡率明显少于氟西汀单独处理组。表明5-HTT在调节肉鸡PASMC的增殖和凋亡方面起重要作用,有可能参与肺动脉高压肉鸡肺血管重构的形成。     

White striping prevalence and its effect on meat quality of broiler breast fillets under commercial conditions

White striping (WS), characterized by white striations on the Pectoralis major muscle, is an emerging problem for the broiler industry. Thus, the impact of WS on meat quality has become a current research topic. In this context, a 2‐year follow‐up study, to reveal the prevalence of WS in broiler integrations, was undertaken. Additionally, a laboratory experiment was conducted to determine the oxidative quality during storage and the differences in proximate composition, colour and fatty acid and amino acid profiles of broiler breast fillets scored visually as normal, moderate and severe. In integrations, the WS incidence increased with increasing broiler age and more than 50% of breast fillets obtained from 32‐ to 35‐day‐old broilers and 36‐ to 39‐day‐old broilers had stripes with different scores. Lower protein and higher fat contents were measured in the moderate and severe scored fillets than the normal fillets (p < 0.001). Severe score stripes induced the formation of less redness on the ventral surface (p < 0.05) and a darker colour on the dorsal surface (p < 0.01). The lowest histidine, arginine and tryptophan amounts were determined in severe fillets (p < 0.05). Moderate and severe scored fillets were rich in polyunsaturated fatty acids implying that they were sensitive to lipid oxidation. That suggestion was further proven by the higher TBARS values. Freeze‐thawing induced the formation of carbonyl compounds, but it did not cause differences in sulphydryl groups. Briefly, we suggest that different WS scores may affect the physicochemical and oxidative quality of breast fillets; however, more studies are needed to assert an accurate and explicit judgement.     

An investigation of a reported case of white striping in broilers

Market reports of white striping in broiler breast fillets have been increasing, which has generated concerns in the broiler meat industry regarding negative effects on consumer acceptance. This study was conducted to macro- and microscopically characterize the condition of white striping at varying degrees of severity on Cobb 500 broiler breast fillets slaughtered at 42 d of age. Carcasses of 2,512 broilers presenting white striping were slaughtered and macroscopically classified according to the degree of severity of the striations as moderate or severe; further histological microscopic evaluation demonstrated degenerative myopathy in both moderate and severe cases, but 75% of those breast fillets were classified as moderate. Typically, the samples classified macroscopically as moderate showed microscopic necrosis only (65.17%) or moderate multifocal necrosis (9.83%), whereas those classified as severe showed diffuse and strong necrosis (25.00%). The proliferation of connective tissue was not observed for either of the degrees of white striping investigated, characterizing this profile as an acute occurrence.     

Epidemiology and significance of chicken infectious anemia virus infections in broilers and broiler parents under nonvaccinated European circumstances

A serologic survey in unvaccinated broiler parent and broiler progeny flocks demonstrated seroconversion against chicken infecrious anemia virus (CIAV) in all parent flocks before or around point of lay and in 38% of the broiler flocks examined at slaughter age. The presence of CIAV antibodies at slaughter of broilers was positively correlated with slaughterhouse condemnation rates. Results indicate that CIAV infections are highly prevalent in both broiler parent and broiler flocks and that CIAV infections in broilers are associated with increased slaughterhouse condemnation.     

天蚕素抗菌肽对817肉杂鸡生长性能及免疫功能的影响

试验旨在研究天蚕素抗菌肽对817肉杂鸡生长性能和免疫功能的影响。选取1日龄817肉杂鸡900羽,随机分为5个处理组（对照组、抗生素组及Ⅰ、Ⅱ、Ⅲ组）,每组6个重复,每个重复30羽。对照组饲喂基础日粮,抗生素组在基础日粮中添加150 mg/kg金霉素,Ⅰ、Ⅱ、Ⅲ组分别在基础日粮中添加100、200和300 mg/kg天蚕素抗菌肽,试验期42 d。结果显示,Ⅱ、Ⅲ组能显著提高1~21日龄817肉杂鸡的平均日增重（P<0.05）,显著降低料重比（P<0.05）;显著提高21、42日龄817肉杂鸡的胸腺、法氏囊和脾脏指数（P<0.05）;显著提高42日龄肉杂鸡的ND抗体水平和T淋巴细胞转化率（P<0.05）,表明在日粮中添加天蚕素抗菌肽能提高817肉杂鸡的生长性能和免疫功能,在本试验条件下,适宜的添加量为200 mg/kg。