紫花苜蓿草粉替代部分精料饲喂舍饲育肥肉牛试验

[目的]为了在舍饲育肥肉牛精料中找到合适的紫花苜蓿草粉替代量,降低饲养成本。[方法]将20%、15%、10%的紫花苜蓿草粉分别替代试验Ⅰ组、Ⅱ组、Ⅲ组中等量的精料,Ⅳ组(对照组)不添加苜蓿草粉,舍饲育肥肉牛。[结果]表明:在相同量的精料饲喂条件下,Ⅰ、Ⅱ、Ⅲ、Ⅳ组(对照组)日采食粗料的量分别为3.65kg、3.62kg、3.51kg和3.54kg,日采食粗料量Ⅰ组Ⅱ组Ⅳ组(对照组)Ⅲ组;经过50d的试验,Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组(对照组)增重分别为60.5kg、59.5kg、56.5kg和57.5kg,Ⅰ组、Ⅱ组、Ⅲ组比Ⅳ组对照组分别提高3.3%、2.4%和-1.6%;育肥牛每增重1kg体重,Ⅰ、Ⅱ、Ⅲ和Ⅳ组(对照组)饲料成本总计分别为7.33元、7.49元、7.87元和7.99元。[结论]用15%～20%的紫花苜蓿草粉来替代等同量的精料舍饲育肥肉牛,可以降低肉牛饲养成本,提高经济效益。     

干旱半干旱区肉牛育肥典型日粮筛选试验

[目的]为筛选原料来源广泛、价廉物美的原材料进行育肥肉牛日粮配制。[方法]选择年龄18~24月龄、体重250~300kg健康的西门达尔杂种肉牛30头,随机分为试验Ⅰ、Ⅱ组,每组15头;试验Ⅰ组、Ⅱ组粗饲料分别为青贮玉米秸秆、氨化麦秸,自由采食。试验Ⅰ组随机分为A、B、C三个组,试验Ⅱ组随机分为D、E、F三个组,每组平均5头,依次分别饲喂混合精料配方1、配方2和配方3,育肥牛在同舍以组为单位分栏饲喂90天后。[结果]显示:试验Ⅰ组日增重比试验Ⅱ组高13.98%(P0.05)、饲料报酬高9.55%;其中试验Ⅰ组中B组的日增重1.34kg,分别比A、C、D、E、F组提高13.56%(P0.05)、16.52%(P0.0541.05%(P0.01)、11.67%(P0.05)和25.23%(P0.01),饲料报酬3.77:1,分别比C、D、E、F组提高9.16%、9.59%、5.28%和11.29%。试验Ⅱ组中E组的平均日增重为1.20kg、饲料报酬为3.98:1,同组育肥效果最好;头均纯收入试验Ⅰ组高于试验Ⅱ组295.2元,试验Ⅰ组B组效益最好,试验Ⅱ组E组效益最好。[结论]肉牛育肥生产中,在日粮精料相同情况下,日粮中饲喂青贮玉米秸秆育肥效果显著好于饲喂氨化麦秸;但选用青贮玉米秸秆为粗饲料时,选用B组混合精料配方育肥效果最好;选用氨化麦秸为粗饲料时,选用E组混合精料配方育肥效果最好。两个粮配方在定西及类似地区均有取材方便、价格较低的特点,值得在肉牛育肥中推广。     

全混合日粮压块饲料育肥肉牛试验研究

分别采用玉米秸秆、稻草秸秆与精料设计全混合日粮,配制压缩块状饲料进行肉牛育肥及屠宰测定试验,研究秸秆与精料分开的传统饲养模式与压块饲料饲喂肉牛对肉牛育肥效果的影响。结果,分别饲喂玉米、稻草秸秆与精料全混合日粮压块饲料的两试验组(Ⅰ和Ⅱ)育肥牛平均日增重分别为1259．26±161．11 g和1259．26±82．82 g,而对照组分别采用传统的精粗料分开不补喂/补喂蛋白补充料育肥牛平均日增重分别为506．17±228．48 g和318．93±119．80 g,各试验组与对照组牛之间平均日增重差异均达到极显著水平(P＜0．01);试验组Ⅰ和Ⅱ、Ⅲ和Ⅳ(对照)间平均日增重均无明显差异(P＞0．05),表明以玉米秸秆或稻草秸秆与精料补充料等复合配制而成的全混日粮压块饲料,育肥肉牛效果较秸秆与精料分开的传统饲养模式饲喂内牛育肥效果更为好。     

熟洋蓟花苞片饲喂肉用型西门塔尔种牛效果及效益分析

[目的]利用熟洋蓟花苞外层片饲喂肉用型西门塔尔种牛,测量体重增重效果,分析熟洋蓟与玉米青贮作为粗料在相同的饲养环境条件下牛只饲养的经济效益情况。[方法]选取40头8~10月龄的肉用型西门塔尔育成母牛及20头哺乳母牛(犊牛在1月龄内)分别随机分成两组,Ⅰ组、Ⅱ组为育成母牛分别饲喂熟洋蓟和玉米青贮,Ⅲ、Ⅳ组为哺乳母牛分别饲喂熟洋蓟和玉米青贮;粗料按采食量添加,精料和青干草投放量育成牛两组相同、哺乳牛两组相同,犊牛精料均为自由采食,60d后称重。[结果]饲喂熟洋蓟和玉米青贮的Ⅰ组、Ⅱ组育成母牛60d后平均体重及日增重分别为307.72±13.94kg、1154±206g和278.28±17.60kg、711.53±187.43g;Ⅲ组、Ⅳ组哺乳母牛饲喂熟洋蓟和玉米青贮后其犊牛60d后平均体重及日增重分别为119.74±8.87kg、1115.83±247.13g和106.48±11.63kg、960.33±276.65g;差异均显著(P0.05)。[结论]分析通过四个组饲喂熟洋蓟和玉米青贮后牛只增重效果,可以看出,Ⅰ组和Ⅲ组(犊牛)饲喂熟洋蓟增重效果分别优于饲喂玉米青贮的Ⅱ组和Ⅳ组(犊牛);随着牛只对熟洋蓟采食量的增加,青干草采食量也有所增加,但精料量同时逐渐减少,到第35d时可完全不喂精料,可大大降低饲料成本,提高经济效益。     

棕榈粕渣发酵饲料养殖肉牛应用效果研究

[目的]评价棕榈粕渣发酵饲料对肉牛养殖效果的影响,为棕榈粕渣发酵饲料产品的研发与应用提供依据。[方法]选用24头夏洛莱牛与当地黄牛的杂交育成牛为试验对象,随机分成Ⅰ、Ⅱ、Ⅲ组与对照组4个组。在育肥期(14~16月龄),对照组试验牛饲喂精料补充料和基础粗饲料(100%玉米秸秆),试验组Ⅰ、Ⅱ、Ⅲ组试验牛饲喂与对照组相同的精料补充料和分别用10%、20%、30%棕榈粕渣发酵饲料替代玉米秸秆的粗饲料,拴系饲养,进行饲养试验。经过分析肉牛的生长性能、健康状况、经济效益,评价其应用效果。[结果]在育肥期,以棕榈粕渣发酵饲料替代部分(10%、20%、30%)玉米秸秆作为肉牛粗饲料能达到同样的育肥效果;育肥过程中对照组及试验组杂交牛存活率均为100%,健康状况良好;各组盈利排序为试验组Ⅲ >试验组Ⅱ >试验组Ⅰ >对照组。[结论]含有棕榈粕渣发酵饲料的肉牛粗饲料可以降低养殖成本、提高经济效益。     

反刍动物用微生态制剂对西杂肉牛育肥效果的影响

[目的]为了降低肉牛育肥饲养成本,研究反刍动物用微生态制剂对西杂肉牛育肥增重的效果。[方法]试验选择了体况基本相同的西杂公牛24头,采用随机区组设计将牛分为对照组,试验Ⅰ组、试验Ⅱ组、试验Ⅲ组。对照组饲喂基础日粮,试验Ⅰ组在精饲料中加入0.2%的反刍动物用微生态制剂,试验Ⅱ组在精饲料中加入0.4%的反刍动物用微生态制剂,试验Ⅲ组在精饲料中加入0.6%的反刍动物用微生态制剂,对肉牛进行90天育肥试验后,统计分析增重效果和经济效益。[结果](1)试验Ⅰ组和试验Ⅲ组对照组相比日增重显著提高(P0.05),试验Ⅱ组与试验Ⅰ组相比日增重显著提高(P0.05),试验Ⅲ组和试验Ⅱ组相比日增重效果不明显(P0.05).(2)所有试验组肉牛的日增重均高于对照组,其中精料中加入0.4%的反刍动物用微生态制剂时头均日盈利19.13元,比对照组高4.66元,经济效益最好。[结论]反刍动物用微生态制剂在西杂肉牛育肥中可提高饲料的消化利用率,降低肉牛育肥成本,提高肉牛养殖效益。     

全株玉米青贮饲养肉牛最佳日粮组合模式研究

对肉牛常用饲料进行营养价值评定,并选择36头6～24月龄西杂肉牛分4组分别采食不同组合日粮,试验期63～68 d.结果表明,不同饲料之间蛋白含量、有效降解率和有效能含量存在较大的差异.肉牛代谢体重干物质采食量与日粮粗蛋白含量之间存在极显著正相关关系,日增重随代谢体重采食量的增加呈直线增加,经济效益随肉牛日增重的增加而增加.以青贮 秸秆 0.5 kg肉牛浓缩料、青贮 秸秆 2 kg肉牛精料补充料、青贮 牧草 0.5 kg肉牛浓缩料、青贮 牧草 2 kg肉牛精料补充料日粮组合分别饲养西杂肉牛,日增重(ADG)分别为0.66 kg、0.90 kg、0.92 kg、1.08 kg;体况评分(BCS)分别增加0.33分、0.42分、0.56分、0.69分;日盈利分别为3.44元、4.22元、4.70元、4.41元.说明,以全株玉米青贮 优质牧草粗饲料组合饲养肉牛,再补饲含高蛋白和能促进肉牛生长及提高纤维饲料消化率的瘤胃微生物所必须矿物质的肉牛浓缩料或肉牛精料补充料,可使肉牛达到较好的增重,并获得较高的收益.     

桑叶粉添加量对云岭牛增重及经济效益的影响

试验旨在研究桑叶粉添加量对云岭牛增重及经济效益的影响。采用单因素完全随机分组试验设计,选择生长发育良好、健康的云岭牛阉牛18头,随机分为3组,每组6头,组间初始体重差异不显著(P0.05),在日粮中分别添加占精料比例25%桑叶粉(Ⅰ组)、40%桑叶粉(Ⅱ组)、50%桑叶粉(Ⅲ组),使3个试验组的日粮均为能量蛋白相似的饲喂日粮,在相同饲养管理条件下,经过100 d的饲养试验。结果表明:(1)3组牛被毛光滑,膘情良好,试验期间3组牛每天饲喂的精料和桑叶粉均完全采食干净,组间无显著差异(P0.05);青贮采食量不同,依次为Ⅰ组Ⅱ组Ⅲ组,组间也无显著差异(P0.05);试验末重组间差异不显著(P0.05),总增重和日增重均明显增加,总增重和日增重依次为Ⅲ组Ⅱ组Ⅰ组(P0.05),说明增加桑叶粉的添加量能降低青贮粗饲料的摄入量,并显著提高肉牛的总增重和日增重。(2)3组试验牛均取得了良好的经济效益,试验期间精料和青贮粗料的成本合计为Ⅰ组Ⅱ组Ⅲ组,增重效益最高的是添加50%桑叶粉的Ⅲ组,为372.23元/头,最低的是添加25%桑叶粉的Ⅰ组,为293.23元/头,Ⅲ组和Ⅱ组分别比Ⅰ组经济效益高出26.94%和10.28%,说明日粮中添加桑叶粉能促进云岭牛肉牛生长性能的提高,且随着桑叶粉添加量的增加,饲料成本呈现降低趋势,肉牛养殖效益逐渐提高。     

全株甘蔗育肥肉牛试验

利用 1 8头本地黄牛作为供试牛 ,用全株甘蔗作饲料进行了为期 3个月的育肥试验 ,研究了在不同营养水平条件下 (Ⅰ组直接饲喂全株甘蔗而不补料 ,Ⅱ组和Ⅲ组则在饲喂甘蔗的同时分别补饲肉牛浓缩料 0 5kg/头·日、肉牛精料补充料 2kg/头·日 )肉牛的增重效果。结果表明 :Ⅱ组的平均日增重达 555g,与Ⅲ组 (561g)相近 ;而对全株甘蔗干物质的采食量明显高于Ⅰ、Ⅲ组 ,而单位增重的耗料量和饲料成本最低。     

不同营养水平全混合日粮（TMR）饲喂利杂牛育肥效果分析

[方法]研究采用全混合日粮（TMR）饲喂方式,对利木赞牛与本地黄牛杂交改良后代F1进行低、中、高3个不同营养水平（15～18月龄,分别编为试验Ⅰ组、Ⅱ组、Ⅲ组）的日粮配方筛选试验,基础日粮为全株玉米青贮+玉米芯+苜蓿干草+肉牛精料补充料,试验期100 d。[结果]研究结果表明,从平均期末体重、期内总增重及日增重指标来看,试验Ⅲ组（高营养水平）平均日增重达（1.63±0.33） ㎏,高于Ⅰ组（1.58±0.29） kg和Ⅱ组（1.61±0.30） kg,按平均期末体重、期内总增重和日增重排序,为试验Ⅲ组（高营养水平）>Ⅱ组（中营养水平）＞Ⅰ组（低营养水平）,试验结果的趋势表明,同品种组合杂种肉牛不同营养水平,其育肥增重效果不同。但组间差异不显著（P＞0.05）,可能与标本量不足有关。在经济效益方面,随着精补料/增重比重的增加,相应试验组肉牛的产出增加,但同时也增加了养殖成本,从试验组的头均纯收益、新增投入占产出比以及总投入占产出比3个方面进行从低到高的排序为Ⅲ组（高营养水平）＜Ⅱ组（中营养水平）＜Ⅰ组（低营养水平）。[结论]试验结果表明,此结果与其平均日增重和日料的营养水平是相吻合的。因此,为了节本增效,应充分利用宁夏地区的优势杂交肉牛组合,同时辅以标准化的、能够充分利用当地饲草优势的、多元化的、科学的日粮配方。     

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