饲养方式对北京油鸡生长和屠宰性能、肉品质以及肌肉脂肪酸含量的影响

本试验旨在研究不同饲养方式对北京油鸡生长和屠宰性能、肉品质以及肌肉脂肪酸含量的影响。试验选取8周龄北京油鸡公鸡1 200只,体重(561.75±7.39) g,随机分成2个组,对照组为集约化笼养(笼养组),试验组为林下放养(放养组),每组6个重复,每个重复100只鸡。试验分为9～14周龄和15～20周龄2个阶段,试验期间饲喂相同饲粮。结果表明:1) 14周龄,笼养组北京油鸡活体重与放养组相比无显著差异(P>0.05),而20周龄,放养组油鸡活体重较笼养组显著下降(P<0.05); 2个饲养阶段放养组油鸡腿肌率较笼养组显著上升(P<0.05),腹脂率显著降低(P<0.05),而胸肌率组间无显著差异(P>0.05)。2) 20周龄,放养组胸肌和腿肌亮度(L*)和红度(a*)值显著高于笼养组(P<0.05); 2个饲养阶段放养组胸肌黄度(b*)值显著下降(P<0.05),而腿肌b*值组间无显著差异(P>0.05)。3) 20周龄,放养组北京油鸡胸肌粗蛋白质含量较笼养组显著升高(P<0.05),而粗脂肪含量显著下降(P<0.05); 2个饲养阶段放养组北京油鸡胸肌肌苷酸含量较笼养组显著上升(P<0.05),腿肌粗蛋白质和肌苷酸含量显著升高(P<0.05),而粗脂肪含量显著下降(P<0.05);饲养方式对肌肉水分含量无显著影响(P> 0.05)。4)北京油鸡胸肌和腿肌中脂肪酸种类基本一致,棕榈酸、油酸和亚油酸含量最高,放养组肌肉不饱和脂肪酸和必需脂肪酸含量显著高于笼养组(P<0.05),而饱和脂肪酸和总脂肪酸含量显著下降(P<0.05)。综上所述,饲养方式对北京油鸡生长和屠宰性能、肌内脂肪酸的组成和含量存在影响,林下放养方式可改善北京油鸡肌肉品质和肉质风味。     

膨化亚麻籽对北京油鸡生长性能、屠宰性能、血浆生化指标、抗氧化能力和肌肉n-3多不饱和脂肪酸沉积量的影响

本试验旨在研究饲粮添加膨化亚麻籽对北京油鸡的生长性能、屠宰性能、血浆生化指标及肌肉n-3多不饱和脂肪酸(PUFA)沉积量的影响。试验选取10周龄北京油鸡(雌鸡)450只,随机分为5组,每组6个重复,每个重复15只鸡,试验期8周。在基础饲粮中分别添加0(阴性对照)、9%的亚麻籽(阳性对照)及9%、12%、15%的膨化亚麻籽,制成5种试验饲粮,分别命名为E0、F9、E9、E12、E15。结果表明:1)E9组生长性能和屠宰性能与F9组相比无显著差异(P>0.05)。与E0组相比,添加膨化亚麻籽对北京油鸡生长性能和屠宰性能均无显著影响(P>0.05)。2)与F9组相比,E9组血浆超氧化物歧化酶(SOD)的活性和丙二醛(MDA)的含量差异不显著(P>0.05)。相比于E0组,添加膨化亚麻籽显著降低北京油鸡肌肉中SOD的活性(P<0.05),同时显著提高血浆MDA的含量(P<0.05)。3)E12组肌肉中n-3PUFA沉积量最高,为(2.16±0.97)g/kg,是E0组5.68倍,且显著高于E0组(P<0.05),但与F9组无显著差异(P>0.05)。由此可见,亚麻籽膨化后可以显著提高n-3PUFA的沉积量,但相同添加量的亚麻籽和膨化亚麻籽对n-3PUFA的沉积量的影响没有显著差异;综合生产工序及成本,不建议使用膨化亚麻籽作为生产富含n-3PUFA鸡肉的油鸡饲料原料。     

爱拔益加肉鸡和北京油鸡脂肪代谢及其相关基因表达的比较研究

为了探讨引起爱拔益加(AA)肉鸡和北京油鸡脂肪沉积表观差异的内在因素,本研究比较了AA肉鸡(56日龄)与北京油鸡(56日龄和114日龄)的体脂沉积、血脂代谢、脂肪细胞因子浓度、脂肪代谢相关酶活性以及相关基因mRNA的表达量.试验选用1日龄AA肉鸡60只和北京油鸡120只,分别随机分为6个重复.结果表明,56日龄AA肉鸡腹脂率高于同日龄的北京油鸡(P<0.05),但是低于114日龄的北京油鸡(P<0.05).56日龄从肉鸡血浆总甘油三酯、游离脂肪酸和脂联素浓度,血浆脂蛋白酯酶和肝脏苹果酸脱氢酶活性均低于56日龄和114日龄北京油鸡(P<0.05).56日龄AA肉鸡肝脏载脂蛋白A-Ⅰ(apoA-Ⅰ)基因mRNA表达量高于56日龄和114日龄北京油鸡(P<0.05),脂联素基因mRNA表达量高于114日龄北京油鸡(P<0.05).56日龄AA肉鸡腹脂中的甘油三酯脂酶(ATGL)基因和心脏型脂肪酸结合蛋白(H-FABP)基因mRNA表达量高于114日龄的北京油鸡(P<0.05),脂肪型脂肪酸结合蛋白(A-FABP)基因mRNA表达量低于114日龄北京油鸡(P<0.05);56日龄AA肉鸡腹脂过氧化物酶体增殖物激活受体γ(PPARγ)基因mRNA表达量低于56日龄北京油鸡(P<0.05).腹脂A-FABP基因mRNA表达量与腹脂率显著正相关(P<0.05);腹脂ATOL基因、过氧化物酶体增殖物激活受体α(PPARα)基因、肝脏apoA-Ⅰ基因和脂联素基因mRNA表达量均与腹脂H-FABP基因mRNA表达量显著正相关(P<0.05).结果提示:北京油鸡血浆脂蛋白酯酶和肝脏苹果酸脱氢酶活性高于AA肉鸡,从而导致较高的血浆总甘油三酯和游离脂肪酸浓度,这可能是北京油鸡脂肪沉积较高的内在因素之一.A-FABP基因是造成2个品种腹脂沉积量差异的关键基因,H-FABP基因是脂类代谢通路上的关键基因.     

基因表达的影响

 试验旨在研究不同日粮代谢能水平对北京油鸡脂肪沉积及脂蛋白酯酶（LPL）基因mRNA表达影响。试验以3周龄北京油鸡公鸡为研究对象，将480只公鸡随机分为4组，分别饲喂4个代谢能水平的日粮（12.122、12.540、12.958和13.376 MJ/kg），每个处理组5个重复，每个重复24只鸡。试验期为10周。采用荧光定量PCR方法检测LPL基因mRNA表达水平。结果表明，日粮代谢能水平对鸡体脂沉积各项指标和LPL基因mRNA表达水平影响极显著，随日粮代谢能水平提高，各项体脂沉积指标极显著上升，胸肌和腿肌IMF、皮脂重和皮脂率在ME3达到峰值，LPL基因mRNA表达水平在ME2组达到峰值（P＜0.01）。LPL基因mRNA表达水平与腹脂率、皮脂重和皮脂率呈显著正相关（P＜0.05）。研究结果提示，日粮代谢能水平显著影响北京油鸡体脂沉积和LPL基因mRNA表达；LPL基因表达影响北京油鸡体脂沉积状况。     

日粮代谢能水平对北京油鸡脂肪沉积和LPL基因表达的影响

试验旨在研究不同日粮代谢能水平对北京油鸡脂肪沉积及脂蛋白酯酶（LPL）基因mRNA表达影响。试验以3周龄北京油鸡公鸡为研究对象,将480只公鸡随机分为4组,分别饲喂4个代谢能水平的日粮（12.122、12.540、12.958和13.376 MJ/kg）,每个处理组5个重复,每个重复24只鸡。试验期为10周。采用荧光定量PCR方法检测LPL基因mRNA表达水平。结果表明,日粮代谢能水平对鸡体脂沉积各项指标和LPL基因mRNA表达水平影响极显著,随日粮代谢能水平提高,各项体脂沉积指标极显著上升,胸肌和腿肌IMF、皮脂重和皮脂率在ME3达到峰值,LPL基因mRNA表达水平在ME2组达到峰值（P＜0.01）。LPL基因mRNA表达水平与腹脂率、皮脂重和皮脂率呈显著正相关（P＜0.05）。研究结果提示,日粮代谢能水平显著影响北京油鸡体脂沉积和LPL基因mRNA表达;LPL基因表达影响北京油鸡体脂沉积状况。     

共轭亚油酸对北京油鸡肉品质及血清leptin和脂蛋白脂酶的影响

选用1日龄北京油鸡公雏360只,随机分成5个处理,每个处理6个重复,每个重复12只鸡,饲喂玉米豆粕型饲料基础日粮,添加0、0.25%、0.5%、1%、2%共轭亚油酸(CLA),用以研究CLA对北京油鸡脂类代谢和肉质性状的长期影响,试验期18周。结果表明:饲粮CLA提高了饲料利用率(P<0.05),显著性地降低了北京油鸡腹脂率和血清中脂蛋白脂酶(LPL)、leptin,显著增加了肌内脂肪的含量(P<0.05),但对pH值和肉色无显著性影响(P>0.05)。     

胍基乙酸对肉鸡肉品质和腹脂沉积的影响

【目的】试验旨在探究胍基乙酸(guanidinoacetic acid, GAA)对肉鸡肉品质和腹脂沉积的影响。【方法】选取1日龄科宝肉仔鸡90只,随机分为3组,每组5个重复,每个重复6只鸡。试验Ⅰ组(对照组)饲喂基础饲粮,试验Ⅱ、Ⅲ组分别在基础饲粮中添加1.2和3.6 g/kg GAA。饲养周期为42 d。于42日龄采集胸肌、腿肌、肝脏、腹部脂肪及血液样品,测定肉品质、肌肉病及腹脂沉积相关指标。【结果】与试验Ⅰ组相比,试验Ⅱ、Ⅲ组胸肌和腿肌pH_{45 min}极显著或显著增加(P<0.01;P<0.05);试验Ⅱ组胸肌肉色b^*值、腿肌肉色a^*值和失水率均极显著增加(P<0.01),腿肌肉色L^*值、木质肉与白纹肉发生率均显著降低(P<0.05);试验Ⅲ组木质肉发生率显著升高(P<0.05)。试验Ⅱ组腹脂率、腹脂细胞直径均显著低于试验Ⅰ、Ⅲ组(P<0.05),血清甘油三酯(TG)水平显著高于试验Ⅰ、Ⅲ组(P<0.05)。【结论】饲粮中添加1.2 g/kg GAA能...     

饲粮粗蛋白质与赖氨酸水平对北京油鸡育雏期生长性能和血清生化指标的影响

本试验旨在研究饲粮粗蛋白质与赖氨酸水平对北京油鸡（简称油鸡）育雏期生长性能和血清生化指标的影响。选择1日龄油鸡混合雏1 350只，随机分为9组，每组5个重复，每个重复30只鸡（公母各占1/2）。采用3×3因子试验设计，饲粮粗蛋白质水平分别为17%、18%、19%，赖氨酸水平分别为0.85%、1.00%、1.15%，分别统计0～3周龄、4～6周龄和0～6周龄生长性能，6周龄末测定血清生化指标。结果显示：1）饲粮粗蛋白质水平对4～6周龄油鸡周平均采食量及周平均体增重有显著影响（P<0.05），粗蛋白质水平为19%时周平均采食量（251.85 g）与周平均体增重（85.52 g）最大；饲粮赖氨酸水平对4～6周龄油鸡料重比有显著影响（P<0.05），赖氨酸水平为1.00%时料重比最低（2.95）。0～6周龄饲粮粗蛋白质水平对油鸡周平均采食量有影响显著（P<0.05），随着粗蛋白质水平增加周平均采食量逐渐增加，且在粗蛋白质水平为19%时达到最大值（184.58 g）；赖氨酸水平对周平均体增重与料重比有显著影响（P<0.05）,1.00%和1.15%赖氨酸组的周平均体增重均...     

朗德鹅血液性状与体脂沉积间相关关系的研究

以朗德鹅为试验对象,分别测定70日龄时与脂肪代谢有关的血液生化指标和体重、胸肌含脂率、腿肌含脂率、腹脂率、皮脂厚度、肌间脂宽,探讨朗德鹅血液性状与体脂沉积和体重的关系。结果表明:①在所测性状中,公鹅体重和母鹅胆固醇的变异系数较小,所有鹅极低密度脂蛋白、甘油三酯的变异系数均较大。②极低密度脂蛋白与甘油三脂呈显著相关(P<0.05),与其它血液指标相关不显著。③极低密度脂蛋白与腹脂率呈显著相关(P<0.05),与肌间脂肪宽呈极显著相关(P<0.01);胆固醇与活重、皮下脂肪厚度、肌间脂肪宽呈显著正相关(P<0.05);高密度脂蛋白与胸肌含脂率、皮下脂肪厚度呈极显著正相关(P<0.01),与肌间脂肪宽呈显著正相关(P<0.05)。以上结果说明,极低密度脂蛋白可作为培育低脂朗德鹅的遗传指标;甘油三脂可以作为极低密度脂蛋白选择的辅助指标。     

京星黄鸡103与北京油鸡屠体性能及肉品质比较

京星黄鸡103肉鸡配套系是目前唯一含有北京油鸡血缘的黄羽肉鸡培育品种（配套系）。本研究选取京星黄鸡103肉鸡商品代和纯种北京油鸡各120只（公母各半）,比较培育品种和纯种在屠体性能、肉品质和肌肉主要营养成分上的差异。试验鸡同批次孵化出雏,饲养管理条件和饲料营养水平均一致。分别于90和120日龄选取接近各组平均体重的鸡各20只屠宰,检测相关指标。结果表明,京星黄鸡103的生长速度显著快于北京油鸡纯种（P<0.05）,其中90日龄平均体重达1.48 kg,120日龄达1.88 kg,分别比纯种的高24.4%和24.5%;90日龄胸肌重和腿肌重比北京油鸡纯种分别提高24.5%和19.2%,120日龄的分别提高了30.7%和28.9%,但两品种间无显著差异（P>0.05）;90日龄京星黄鸡103胸肌肌内脂肪和粗蛋白质含量显著高于北京油鸡（P<0.05）;胸肌脂肪酸中以硬脂酸和棕榈酸等饱和脂肪酸和花生四烯酸、亚油酸和油酸等不饱和脂肪酸为主,品种之间无显著差异（P>0.05）。综上,京星黄鸡103商品代肉鸡与北京油鸡纯种相比生长速度较快,90日龄达中速型黄羽肉鸡标准,胴体载肉量提升,且基本保持了北京油鸡纯种的肌内脂肪含量高等优良肉品质特性。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -