日粮锰对肉仔鸡组织器官锰、铜、锌沉积的影响

选用 1日龄艾维茵肉仔鸡 ,采用单因子多水平随机化试验设计 ,随机分成 6组 ,每组 3个重复 ,每个重复 8只鸡。在玉米 豆粕型基础日粮中分别添加锰 (MnSO4 ·H2 O) 0 ,40 ,80 ,1 2 0 ,1 60 ,2 0 0mg/kg ,研究日粮锰对肉仔鸡组织器官锰、铜、锌沉积的影响。结果表明 :在肉仔鸡日粮中添加 40 2 0 0mg/kg的锰 ,对胫骨锰、肝脏锰和肾脏锰的沉积有显著的影响 (P <0 0 5) ;日粮锰的添加对肝铜和肾铜沉积无明显影响 (P >0 0 5) ,但日粮锰添加量超过 1 2 0mg/kg时 ,能够减少胫骨铜的沉积 (P <0 0 5) ;对胫骨、肝和肾中锌的沉积无明显影响(P >0 0 5)。     

22～42日龄肉鸡铜、铁、锌、锰不同用量组合的研究

本试验旨在研究饲粮中铜、铁、锌、锰含量对22~42日龄肉鸡生长性能和粪中铜、铁、锌、锰排泄量的影响,进而对微量元素的平衡模式进行探讨。选取940只1日龄爱拔益加(AA)肉公鸡,1~21日龄统一饲喂铜、铁、锌、锰含量分别为16.96、166.66、46.01、60.26 mg/kg的玉米-豆粕型饲粮。试验选用22日龄、体况良好、体重接近的AA肉公鸡900只,随机分为15组,每组6个重复,每个重复10只鸡。对照组饲喂基础饲粮,基础饲粮中铜、铁、锌、锰含量分别为8、125、40、60 mg/kg,试验组饲喂在基础饲粮中按照均匀设计原则添加2~8 mg/kg铜、10~35 mg/kg铁、10~40 mg/kg锌、15~60 mg/kg锰组成的14种试验饲粮。测定肉鸡试验期生长性能,并于38~42日龄时采集粪样测定铜、铁、锌、锰含量。结果表明:1)饲粮铜、铁、锌、锰含量在NRC推荐量至2倍NRC推荐量范围时,对22~42日龄肉鸡的平均日增重(ADG)和料重比(F/G)无显著影响(P0.05)。2)由最优解分析得出,粪中铜排泄量最低为23.11 mg/kg时,饲粮铜、铁、锌、锰含量分别为7.15、116.28、82.82、60.95 mg/kg;铁排泄量最低为438.34 mg/kg时,饲粮铜、铁、锌、锰含量分别为14.78、116.81、38.15、63.72 mg/kg;锌排泄量最低为102.60 mg/kg时,饲粮铜、铁、锌、锰含量分别为7.69、127.40、40.70、133.26 mg/kg;锰排泄量最低为159.37 mg/kg时,饲粮铜、铁、锌、锰含量分别为11.07、136.97、46.13、59.05 mg/kg;粪中铜、铁、锌、锰总排泄量最低为218.94 mg/kg时,饲粮铜、铁、锌、锰含量分别为7.36、125.74、38.23、62.76 mg/kg。综上所述,饲粮铜、铁、锌、锰含量在NRC推荐量至2倍NRC推荐量范围时对22~42日龄肉鸡的生长性能无显著影响;粪中铜、铁、锌、锰任一元素的排泄量均受饲粮中其他微量元素添加量的影响,且针对不同元素最低排泄量存在不同的最佳组合;饲粮铜、铁、锌、锰的含量分别为7.36、125.74、38.23、62.76 mg/kg时,能够满足肉鸡微量元素需要量,同时粪中铜、铁、锌、锰总排泄量最小。     

酵母硒对断奶獭免生长性能的影响

选择35日龄健康獭兔80只,按体重随机分为4组,在基础日粮中分别添加0、0．1、0．3、0．5mg／kg酵母硒进行饲喂,试验期30d。结果表明：添加酵母硒能提高獭兔的日增重、血清总蛋白、球蛋白与T3水平,降低料重比与血清T4水平,其最适添加量为0．3mg／kg。     

日粮中添加氨基酸络合锌、铜、锰对蛋鸡产蛋性能、免疫及组织抗氧化机能的影响

试验选择216只3周龄海兰褐蛋鸡，随机分成3个处理组：A组蛋鸡饲喂生产中实用日粮(Zn、Cu、Mn分别为60、10、60mg／kg)；B组日粮为在A水平的基础上添加硫酸锌、铜和锰；C组日粮为在A的基础上添加氨基酸锌、铜、锰。B和C日粮组锌、铜、锰的添加水平分别为100、17、100mg／kg。结果表明，在实用日粮基础上增加有机微量元素锌、铜、锰能提高蛋鸡的存活率和鸡蛋品质，改善细胞免疫和体液免疫，增强肝脏和脾脏组织抗氧化能力，而增加相同剂量的无机盐对上述指标无明显有益的影响。     

乳酸锌对獭兔生产性能的影响

选择35—40日龄法系獭兔120只，体重750±50．25g，平均分为4个处理，每个处理3个重复。对照组日粮不添加锌制剂，试验Ⅰ组添加一水硫酸锌350mg／kg，Ⅱ组添加一水硫酸锌255mg／kg和乳酸锌150mg／kg，Ⅱ组添加乳酸锌550mg／kg，试验期28d。结果表明：试验Ⅱ组的生产性能最佳，与对照组、试验Ⅰ组和Ⅲ组相比，日增重分别显著提高11．77％、7．81％和9．77％（P〈0．05），料肉比分别显著降低16．45％、4．73％和4．76％，腹泻率分别降低80．12％、67％和75．19％．一级皮皮张等级分别提高80、6333和60个百分点。     

降低日粮中铜铁锌锰添加水平对肉鸡生产性能及排泄的影响

选取96只18日龄健康无残、体质量无差异艾维因肉鸡,随机分为3组,每组4个重复,每重复8只鸡。3个试验处理组日粮均为氨基酸平衡日粮,将铜、铁、锌和锰分别添加于对照组8、80、40和60 mg/kg,试验1组4、40、20和30 mg/kg,试验2组0、0、0和0 mg/kg,研究降低日粮中铜铁锌锰添加水平对肉鸡生长性能及排泄的影响。试验结果表明,降低日粮中铜铁锌锰的添加水平,显著影响肉鸡的生长性能(P0.05)。     

日粮硒碘水平与产蛋鸡血浆及蛋中硒碘含量的相关性研究

以含Se0．2mg／kg、10．5mg／kg日粮（对照组），舍Se1．2mg／kg、150mg／kg日粮（试验Ⅰ组），含Se2．2mg／kg、Ⅰ100mg／kg日粮（试验Ⅱ组）分别饲喂产蛋母鸡8周，测定日粮硒碘水平对产蛋鸡血浆及蛋白、蛋黄硒碘含量的影响。相关性检验结果表明：日粮硒与血浆硒、蛋黄硒，血浆硒与蛋黄硒、蛋白硒，日粮碘与血浆碘、蛋黄碘，血浆碘与蛋黄碘均呈强正相关；提示产蛋母鸡是日粮中硒和碘向蛋中转运的良好载体。     

有机微量元素对养鸡生产的影响

试验的目的在于检测肉鸡日粮中添加2．5mg／kg的有机铜，10mg／kg的有机锌、有机铁和有机锰及试验2、3、4和6倍的剂量后，与更高添加剂量的无机矿物质元素相比，观察对肉鸡生长性能和矿物排泄量的影响，并检测有机矿物元素对商品蛋鸡生产性能和鸡蛋品质的影响。     

不同硒水平对生长育肥猪生产性能的影响

试验研究了宁夏常用饲粮中不同硒水平(添加硒0，0．15，0．30，0．45，0．60mg／kg)对生长育肥猪生产性能的影响。结果表明：(1)在饲粮中添加不同水平的硒，对各个饲养阶段生长育肥猪的日增重、日采食量和饲料报酬没有明显影响。但从全期来看。饲粮中添加硒0．30mg／kg时日增重最高。料重比最低。(2)综合肉质品质各项指标的测定结果。饲粮中添加硒0．30，0．45，0．60mg／kg时，肌肉保水性、嫩度较好。以饲粮中添加硒0．30mg／kg时为最好。补硒组肉色评分、肌肉新鲜度和抗应激能力均较缺硒组高，肉色评分以饲粮中添加硒0．30mg／kg时最为理想。(3)在宁夏缺硒地区的玉米-豆粕、胡麻饼型饲粮中。从满足正常生长发育的代谢需要、改善肉的品质及降低发病率等方面综合考虑。在15～90kg体重的生长育肥猪基础饲粮中建议添加0．30mg／kg硒为宜，饲粮硒水平为0．33mg／kg，特别是在15～30kg体重的仔猪阶段。从降低发病率的角度考虑。硒的添加量可适当提高。     

日粮中添加硒、碘对仔猪生长性能的影响

试验选择长白＊荣昌一代杂种仔猪，研究了基础日粮中添加0．1mg／kg、0．2mg／kg和0．3mg／kg的硒和碘对仔猪生长性能的影响。结果表明，仔猪基础日粮中添加硒和碘显著提高了仔猪日增重，且0．3mg／kg处理效果最好。3种处理试验期60天每头仔猪仅饲料成本就分别节约8．25元、21．98元和39．50元。     

液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量的不确定度评估

采用液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量,对标准溶液、体积、质谱峰面积、浓缩过程及回收率等测定不确定度因素进行了分析,通过评定各不确定度分量及标准不确定度,得出11种β-受体激动剂的扩展不确定度在0.7 ～ 1.1 ng/mL范围内.由各因素对合成不确定度的贡献比分析可知,影响较大的因素为试验回收率及标准溶液浓度.     

电感耦合等离子-质谱法测定饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅

应用电感耦合等离子-质谱技术(ICP-MS),建立饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅等元素的测定方法。对饲料样品的前处理方法、仪器工作参数和11种元素标准曲线进行优化;并以加标回收、分析方法比对和重复测试说明方法的准确性和精密性。方法在0～1 000 ng/ml范围内线性良好,仪器检出限为0.557 7～5.072 ng/ml,具有良好的精密度,其回收率在88.1%～104.4%之间,相对标准偏差小于5.0%。同时与原子吸收和原子荧光方法进行比对,测定结果相近。所建立的方法简单、快速,可替代原子吸收和原子荧光方法测定饲料中的11种金属元素,为饲料的质量控制提供理想的元素分析方法。     

Supplementation of broodmares with copper, zinc, iron, manganese, cobalt, iodine, and selenium

In experiment 1, 6 pregnant mares received a concentrate that contained a trace mineral premix that provided 14.3 mg Cu, 40 mg Zn, 28 mg Fe, 28 mg Mn, 0.08 mg Co, 0.16 mg I, and 0.16 mg Se/kg concentrate (group A). Seven mares received the same concentrate plus 502 mg Zn and 127 mg Cu once daily (group B). No differences (P > .05) in foal growth data, or Cu, Zn, and Fe concentrations of mare milk, mare serum, or foal serum were observed. In experiment 2, 6 pregnant mares received the same concentrate as group A (group C), and 8 mares received the same concentrate fortified with 4× the trace mineral premix (group D). Group C mares had higher serum Zn concentration at 1 day (P < 0.01) and 56 days (P < 0.04). Group C mares had higher milk Fe concentration at 28 days (P < .01), and group D mares had higher milk Cu concentration at 56 days (P < .01). Group C foals had higher serum Cu concentration at 14 days (P < .03). The results from this study provide no evidence to indicate that supplementing late gestating and lactating mares with higher dietary trace mineral levels than those recommended currently by NRC has any influence on foal growth and development, or on the Cu, Zn, and Fe concentrations of the mare milk, mare serum, or foal serum.     

文山黄牛的现状与保种措施

文章阐述了文山黄牛的品种特性、现状和保种措施。文山牛保种可采用原产地活体保种,迁地活体保种和现代生物技术保种等多种方式。文山牛体型较大,性情温顺,产肉性能好、活动敏捷、结构紧凑、肌肉强健、肉品质优良、耐粗饲、适应性广、繁殖力和抗病力均较强等特点。文山牛是云南省一个地方良种,种质资源保护刻不容缓。     

Comparisons of Angus, Charolais, Galloway, Hereford, Longhorn, Nellore, Piedmontese, Salers, and Shorthorn breeds for weight, weight adjusted for condition score, height, and condition score of cows

Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size.     

Concentrations of strontium,barium, cadmium,copper, zinc,manganese, chromium,antimony, selenium,and lead in the liver and kidneys of dogs according to age,gender, and the occurrence of chronic kidney disease

This study was conducted to measure the concentrations of strontium (Sr), barium (Ba), cadmium (Cd), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), antimony (Sb), selenium (Se), and lead (Pb) in canine liver, renal cortex, and renal medulla, and the association of these concentrations with age, gender, and occurrence of chronic kidney disease (CKD). Tissues from 50 dogs were analyzed using inductively coupled plasma mass spectrometry. Cu, Zn, and Mn levels were highest in the liver followed by the renal cortex and renal medulla. The highest Sr, Cd, and Se concentrations were measured in the renal cortex while lower levels were found in the renal medulla and liver. Female dogs had higher tissue concentrations of Sr (liver and renal medulla), Cd (liver), Zn (liver and renal cortex), Cr (liver, renal cortex, and renal medulla), and Pb (liver) than male animals. Except for Mn and Sb, age-dependent variations were observed for all element concentrations in the canine tissues. Hepatic Cd and Cr concentrations were higher in dogs with CKD. In conclusion, the present results provide new knowledge about the storage of specific elements in canine liver and kidneys, and can be considered important reference data for diagnostic methods and further investigations.