壳寡糖对肉鸡生长性能、屠宰性能、胸肌肉品质及氧化稳定性的影响

试验旨在研究饲粮中添加不同水平壳寡糖对肉鸡生长性能、屠宰性能、胸肌肉品质及氧化稳定性的影响。选取1日龄雌性AA肉鸡264只,随机分为4组,每组6个重复,每个重复11只鸡。对照组饲喂基础饲粮,试验组分别在基础日粮中添加100、200、400 mg/kg壳寡糖（COS）,试验期42 d。结果表明：与对照组相比,饲粮中添加100 mg/kg COS提高了1～14日龄肉鸡平均日增重（ADG）;添加200 mg/kg COS提高了1～14、15～42、1～42日龄肉鸡ADG且降低了耗料增重比（F/G）(P<0.05);添加400 mg/kg COS提高了1～14日龄肉鸡F/G(P<0.05),降低了ADG(P<0.05);饲粮添加100、200mg/kgCOS提高了肉鸡胸肌宰后pH24h(P<0.05),添加200、400 mg/kg COS降低了滴水损失（P<0.05）;饲粮中添加200 mg/kg COS提高了谷胱甘肽过氧化酶活性（P<0.05）,添加200、400 mg/kg COS降低了胸肌丙二醛含量（P<0.05）;饲粮中添加100、200、4...     

饲粮中添加葛根总黄酮对爱拔益加肉鸡生长性能及肉品质的影响

本试验旨在研究饲粮中添加不同水平葛根总黄酮对爱拔益加(AA)肉鸡生长性能及肉品质的影响。选择健康1日龄AA肉鸡275羽,随机分为5个组,每组5个重复,每个重复11羽鸡。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加10、50、250、1 250 mg/kg葛根总黄酮。试验期42 d。结果表明:1)10 mg/kg添加组AA肉鸡的平均日增重在8~14日龄、15~21日龄和29~35日龄时均显著高于对照组(P0.05),但在22~28日龄时显著低于对照组(P0.05);250 mg/kg添加组AA肉鸡的平均日增重在8~14日龄时显著高于对照组(P0.05)。10 mg/kg添加组AA肉鸡的料重比在15~21日龄、29~35日龄和36~42日龄时显著低于对照组(P0.05),但在22~28日龄时显著高于对照组(P0.05)。各组AA肉鸡的平均日采食量差异不显著(P0.05)。2)与对照组相比,10 mg/kg添加组AA肉鸡胸肌、腿肌的亮度(L*)值显著降低(P0.05),红度(a*)值有升高趋势但差异不显著(P0.05);250 mg/kg添加组腿肌亮度值显著低于对照组(P0.05);50 mg/kg添加组胸肌、腿肌的黄度(b*)值均显著低于对照组(P0.05)。与对照组相比,250、1 250 mg/kg添加组AA肉鸡的胸肌剪切力显著降低(P0.05);250 mg/kg添加组的胸肌水分含量显著高于对照组(P0.05)。结果表明,饲粮中添加10 mg/kg的葛根总黄酮可提高AA肉鸡的生长性能,但添加250 mg/kg的葛根总黄酮可改善肌肉的色泽和嫩度。     

西瓜皮多糖对肉仔鸡生长性能及胴体性能的影响

试验旨在研究西瓜皮多糖对肉仔鸡生长性能及胴体性能的影响。选用108只1日龄体质量均匀的科宝肉鸡,随机分为3组,每组6个重复,每重复6只鸡。分别饲以西瓜皮多糖添加量为0(对照组)、250和500 mg/kg的饲粮。结果表明:各试验组对21日龄肉鸡生长性能和42日龄肉鸡胴体性能均无显著影响,也不具有显著的趋势(P0.10);添加250 mg/kg西瓜皮多糖能显著提高42日龄肉鸡的平均日采食量(P0.05);添加250和500 mg/kg西瓜皮多糖均能显著提高42日龄肉鸡的料重比(P0.05);添加500 mg/kg西瓜皮多糖能显著提高21日龄肉鸡的胸肌率(P0.05),并具有降低腹脂率和腿肌率的趋势(P0.10)。结果表明:饲粮中添加西瓜皮多糖具有改善肉鸡生长性能和胴体性能的效果,同时也可能存在负面影响,并且不同添加水平对不同生长阶段的肉鸡的影响程度也不同。     

D-泛酸钙对黄羽肉鸡生长性能、肉品质、抗氧化能力和免疫功能的影响北大核心CSCD

本试验旨在研究饲粮中添加不同水平D-泛酸钙对1~70日龄黄羽肉鸡生长性能、肉品质、抗氧化能力和免疫功能的影响,以确定黄羽肉鸡饲粮中D-泛酸钙的适宜添加水平。试验选取960羽1日龄健康黄羽肉公鸡(梅黄1号),随机分为6组,每组8个重复,每个重复20羽。6个组分别在基础饲粮中添加0(对照组)、10、15、20、25和30 mg/kg的D-泛酸钙。试验期70 d,分为前期(1~35日龄)和后期(36~70日龄)2个阶段。结果表明:1)随着饲粮中D-泛酸钙添加水平的提高,肉鸡1~35日龄平均日增重(ADG)、36~70日龄料重比(F/G)以及1~70日龄ADG和F/G均呈二次曲线变化(P<0.05)。与对照组相比,饲粮中添加20 mg/kg的D-泛酸钙显著提高1~70日龄ADG(P<0.05),饲粮中添加15~30 mg/kg的D-泛酸钙显著降低1~70日龄F/G(P<0.05)。2)随着饲粮中D-泛酸钙添加水平的提高,肉鸡胸肌滴水损失呈二次曲线变化(P<0.05),且与对照组相比,饲粮中添加10~30 mg/kg的D-泛酸钙显著降低胸肌滴水损失(P<0.05)。3)随着饲粮中D-泛酸钙添加水平的提高,肉鸡35和70日龄血清总抗氧化能力(T-AOC)和丙二醛(MDA)含量呈二次曲线变化(P<0.05)。与对照组相比,饲粮中添加15~25 mg/kg的D-泛酸钙显著提高血清T-AOC(P<0.05),饲粮中添加10~30 mg/kg的D-泛酸钙显著降低血清MDA含量(P<0.05)。4)随着饲粮中D-泛酸钙添加水平的提高,肉鸡35和70日龄血清免疫球蛋白G(IgG)含量呈二次曲线变化(P<0.05),且与对照组相比,饲粮中添加15和20 mg/kg的D-泛酸钙显著提高血清IgG含量(P<0.05)。5)随着饲粮中D-泛酸钙添加水平的提高,肉鸡70日龄血清白介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)含量呈二次曲线变化(P<0.05),且与对照组相比,饲粮中添加15~30 mg/kg的D-泛酸钙显著降低血清IL-6和TNF-α含量(P<0.05)。6)以生长性能、肉品质、抗氧化能力和免疫功能为评价指标,通过二次曲线回归分析,1~35日龄和36~70日龄肉鸡饲粮中D-泛酸钙的适宜添加水平分别为19.73~25.21 mg/kg和14.97~23.40 mg/kg。综上所述,饲粮中添加D-泛酸钙可提高黄羽肉鸡生长性能、肉品质、抗氧化能力和免疫功能,经综合评价,推荐黄羽肉鸡玉米-豆粕型饲粮中D-泛酸钙的添加水平为14.97~25.21 mg/kg。     

厚朴总酚对黄羽肉鸡生长性能、肉品质和抗氧化功能的影响

本试验旨在研究厚朴总酚对黄羽肉鸡生长性能、肉品质和抗氧化功能的影响。试验选取1日龄黄羽肉鸡360只,随机分为5组,每组6个重复,每个重复12只。对照组饲喂基础饲粮;抗生素组1～28日龄饲喂基础饲粮+20 mg/kg抗敌素和12 mg/kg黄霉素,29～56日龄饲喂基础饲粮+12 mg/kg黄霉素;厚朴总酚添加组分别饲喂在基础饲粮中添加50、150和250 mg/kg厚朴总酚的饲粮。试验期56 d。结果表明:1) 29～56日龄和1～56日龄,50 mg/kg厚朴总酚添加组黄羽肉鸡平均日采食量显著高于抗生素组(P0.05),黄羽肉鸡料重比随厚朴总酚添加水平的提高呈现二次变化(P0.05)。2) 56日龄时,50和150 mg/kg厚朴总酚添加组黄羽肉鸡胸肌pH(45 min和24 h)与抗生素组相比显著提高(P0.05),且150 mg/kg厚朴总酚添加组黄羽肉鸡胸肌肉色45 min红度值显著高于其他各组(P0.05),150 mg/kg厚朴总酚添加组黄羽肉鸡胸肌滴水损失(24 h)和失水率显著低于对照组和抗生素组(P0.05)。3) 28日龄时,150 mg/kg厚朴总酚添加组黄羽肉鸡血清超氧化物歧化酶(SOD)和过氧化氢酶活性与抗生素组差异不显著(P0.05),且血清SOD活性显著高于其他组(P0.05); 56日龄时,150 mg/kg厚朴总酚添加组黄羽肉鸡肝脏丙二醛含量显著低于对照组(P0.05)。综上所述,饲粮中添加厚朴总酚能提高黄羽肉鸡生长性能,改善肉品质,增强抗氧化功能,且以150 mg/kg的添加水平为佳。     

植物源乳化剂对肉鸡生产性能及脂肪代谢的影响

用1日龄公母混合肉鸡432只,随机分成4组,每组设3个重复。分别在基础日粮中添加0、200、250、300mg/kg的植物源脂肪乳化剂,进行饲养试验,42 d屠宰。结果显示,乳化剂显著提高了肉鸡42 d日增重(P0.05)及降低料重比(P0.05),以300 mg/kg剂量组最优。300 mg/kg组肉鸡的腿胸肌率和腹脂率显著提高(P0.05)。乳化剂显著提高了血清游离脂肪酸浓度(P0.01),血清与肝脏中胆固醇浓度(P0.05),腹脂与胸肌中脂蛋白脂酶的比值(P0.05);降低肝脏中苹果酸脱氢酶活性(P0.05),腹脂、胸肌中脂蛋白脂酶活性(P0.05)。研究表明,植物源乳化剂能提高日粮脂肪的消化率,促进肉鸡生长。     

日粮硒水平对22～42日龄肉仔鸡生长性能及肉品质的影响

为研究日粮硒水平对22～42日龄肉仔鸡生长性能和肉品质的影响,试验选用380只1日龄Arbor Acres (AA)肉公雏,1～21日龄统一饲喂同种正常添加无机硒的玉米-豆粕型日粮(含硒0.47 mg/kg),于22日龄从中选取体重接近的336只鸡,随机分成6个处理组,每组7个重复,每个重复8只鸡。分别饲喂不添加硒的玉米-豆粕型基础日粮(对照组,含硒0.015 mg/kg)和在基础日粮中分别添加0.10、0.20、0.30、0.40和0.50 mg/kg硒(以亚硒酸钠形式添加)的试验日粮,试验期21 d。结果表明,日粮中添加不同硒水平对22～42日龄肉仔鸡平均日增重、平均日采食量和料重比均无显著影响(P0.05);对42日龄肉仔鸡屠宰率、全净膛率、胸肌率、腿肌率和腹脂率均无显著影响(P0.05);日粮中添加不同硒水平对42日龄肉仔鸡腿肌剪切力和胸肌肉色L~*值有显著影响(P0.05),其中添加0.50 mg/kg硒处理组肉鸡的腿肌剪切力最低,添加0.20和0.50 mg/kg硒处理组肉鸡的胸肌肉色L~*值最低,但其他肉质性状指标在各组间均无显著差异(P0.05)。综上所述,玉米-豆粕型基础日粮中添加不同水平硒对22～42日龄肉仔鸡生长性能与42日龄肉仔鸡胴体性状均无显著影响,但日粮中添加0.50 mg/kg硒降低了腿肌剪切力和胸肌L~*值,对肉品质有一定的改善作用。     

大蒜粉对肉鸡屠宰性能、肉品质及抗氧化功能的影响

试验旨在研究大蒜粉对肉鸡屠宰性能、肌肉品质、常规化学成分和抗氧化功能的影响。选用1日龄艾拔益加(AA)肉仔鸡480只,随机分为4个处理组,每组8个重复,每个重复15只。空白对照组饲喂基础日粮,抗生素组在基础日粮中添加75 mg/kg金霉素,试验组分别在基础日粮中添加1 000 mg/kg(低剂量)和2 000 mg/kg(高剂量)大蒜粉。试验期42 d。结果表明:与空白对照组相比,日粮添加1 000 mg/kg大蒜粉提高了肉鸡屠体重、胸肌重、腿肌重和pH_24h(P<0.05),提高了肉鸡腿肌的粗蛋白质含量、总超氧化物歧化酶(T-SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶活性(GPx)活力(P<0.05),降低了肉鸡胸、腿肌肉24 h亮度和粗脂肪含量及腿肌蒸煮损失率(P<0.05);日粮添加1 000 mg/kg和2 000 mg/kg大蒜粉均提高了肉鸡胸肌的粗蛋白质质含量、总抗氧化能力(T-AOC)、T-SOD和GPx及核因子E2相关因子2(Nrf2)、SOD1和GPx基因的表达量(P<0.05),降低了肉鸡胸肌的蒸煮损失率和丙二醛...     

飞机草总黄酮对AA肉鸡生长性能、免疫器官指数和血清免疫球蛋白水平的影响

目的:研究飞机草总黄酮提取物对AA肉鸡生产性能、免疫器官指数和血清免疫球蛋白的影响,探讨飞机草总黄酮提取物作为饲料添加对肉鸡的应用效果。方法:选用1日龄AA肉鸡160只,随机分成4组,每组4个重复,每个重复10只鸡。对照组饲喂基础日粮,试验组在基础日粮中分别添加100 mg/kg、200 mg/kg、400 mg/kg的飞机草总黄酮,试验期为42 d。结果:在整个试验期中,添加不同浓度的飞机草总黄酮对肉鸡日均增重、料重比、胸肌率的影响显著(P0.05),添加400 mg/kg的飞机草总黄酮对肉鸡胸腺指数、法氏囊指数、Ig G、SIg A影响显著(P0.05)。结论:飞机草总黄酮提取物能够促进肉鸡生长,改善肉鸡的肉用性能,提高肉鸡的免疫功能。     

维生素E和有机锌对肉鸡生长性能、免疫和抗氧化性能及血清、组织维生素含量的影响

研究日粮添加维生素E(VE)和蛋氨酸锌对肉鸡生长性能、免疫和抗氧化性能及血清、组织维生素含量的影响。1350只健康的雌性1 d肉仔鸡被随机分为9组,每组5个重复,每个重复30羽。试验日粮采用3(0、200和400 mg/kg VE)×3(0、50和100 mg/kg锌)多因子设计试验,试验共进行35 d。结果显示:日粮VE或有机锌水平对肉鸡日增重、日采食量、料重比和死亡率均无显著影响(P0.05);日粮添加100 mg/kg锌较无锌组显著提高了肉鸡绵羊红细胞抗体和Ig G的含量(P0.05);日粮添加50或100 mg/kg锌较无锌组显著提高了脾脏和胸腺的重量(P0.05);日粮添加VE显著提高了肉鸡绵羊红细胞抗体和Ig G的含量(P0.05);随着日粮VE添加水平的升高,血清SOD、GHS-Px活性表现为线性升高(P0.05),而MDA含量线性下降(P0.05);日粮锌和VE添加水平对MDA含量的影响表现为显著交互作用(P0.05)。随着日粮锌添加水平的升高,胸肌、腿肌和肝脏中锌的沉积量显著升高(P0.05),且随着日粮锌或VE添加水平的升高,肝脏、胸肌和腿肌中VE含量线性升高(P0.05)。随着日粮锌添加水平的升高,血清锌含量显著线性升高(P0.05),同时显著降低了血清铁和铜含量(P0.05)。结果表明:在本试验添加下,日粮添加VE和有机锌(蛋氨酸锌)可以影响血清和组织中微量元素和维生素的含量,促进肉鸡免疫反应。日粮添加100 mg/kg锌和400 mg/kg VE可以提高肉鸡肌肉的抗氧化性能。     

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.     

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

Tropical Animal Health and Production -     

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.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

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