盐胁迫下三种柳枝稷生理特性及同工酶研究

以柳枝稗低地型品种Alamo和高地型品种Caddo、Dacotah为材料,采用终浓度为250mmol/L的Na~+溶液进行处理,研究盐胁迫对三种柳枝稷生理特性的影响。结果表明:三种柳枝稷受到盐胁迫时,相对含水量(RWC)的变化程度为CaddoDacotahAlamo,在胁迫5d时电导解质渗透率(EL)的变化为Caddo AlamoDacotah。叶片和根系中丙二醛(MDA)含量随盐胁迫时间的延长呈先下降再上升的趋势,其中,品种Caddo的MDA含量比率(叶片/根系)最高,Dacotah次之,Alamo最小。品种Caddo叶脯氨酸含量变化较大,5d时达到最大值3.45μmol/g·FW。各处理天数下,品种Caddo叶片和根系的可溶性蛋白含量均为最高。品种Caddo叶片和根系APX活性均随胁迫时间增加呈上升趋势,处理10d时,叶片APX活性达7712.20U,与其他两个品种差异极显著(P0.01),品种Dacotah叶片和根系CAT活性随胁迫时间增加均呈先上升再下降的趋势,在处理5d时分别达到最高峰值464.46U和111.63U,与其他两个品种差异极显著(P0.01),在5d、10d盐胁迫处理下,叶片SOD活性均以Caddo品种最高。同时测定了胁迫10d时3个品种根系的抗氧化同工酶,其中APX产生3种同工酶,SOD产生4种同工酶,CAT产生1种同工酶。初步评价表明,3个品种耐盐性依次为:AlamoDacotahCaddo。     

不同季节对肥脂型Z型北京鸭生长性能的影响

笔者通过试验测定了肥脂型Z型北京鸭春、夏、秋、冬四个季节的生长性能。结果显示,试验鸭春、夏、秋、冬四个季节各组之间料重比差异显著(P0.05),其中秋季和夏季之间差异极显著(P0.01);各季节之间成活率差异不显著(P0.05),但夏季有降低的趋势;每只平均利润夏季和冬季之间无显著差异(P0.05),但与春季、秋季相比差异显著(P0.05)。综合生长性能指标和经济效益分析,在自然环境温度下,秋季最适宜肥脂型Z型北京鸭的生长,其次为春季。     

限饲对肉用羔羊组织器官生长发育的影响

文章旨在讨论营养限饲对20～35 kg杜寒杂交公羔组织和器官发育的影响.将21只试验羊随机分为3组,按照自由采食(AL组)、自由采食量的70％ (IR70组)和自由采食量的40 ％(IR40组)3个水平饲喂,每组7只羊.当AL组的试验羊体重达35 kg时21只羊全部屠宰,测定各胃室、重要组织及内脏器官的增重与发育情况.结果表明:AL组瘤胃重占胃总重比例最高,为67.08％,与IR70组差异不显著(P＞0.05);肝脏重占宰前活重比例以AL组最高,显著高于IR70组和IR40组(P＜0.05).说明营养限饲会显著影响杜寒杂交公羔内脏器官的增重与发育;对4个胃室的重量与发育比例的影响程度不一致.     

高温胁迫对草地早熟禾抗氧化酶活性及其同工酶图谱的影响

为阐明冷季型草坪草抗氧化酶对高温的胁迫响应,以草地早熟禾(Poa pratensis)耐热品种‘热力’(Thermal Blue)、中耐热品种‘大师’(Utmost)和热敏感品种‘长征’ (Excursion)为试验材料,动态研究45℃/40℃(昼/夜)高温胁迫下叶片中5种抗氧化酶活性的变化.结果表明:45℃/40℃高温胁迫使得3个草地早熟禾品种的超氧化物歧化酶(SOD)活性升高;耐热品种‘热力’ 过氧化物酶(POD)活性呈先升高后降低的趋势,‘大师’和‘长征’ POD活性变化不显著;3个草地早熟禾品种随高温胁迫时间的延长过氧化氢酶(CAT)和谷胱甘肽还原酶(GR)活性明显降低;‘热力’抗坏血酸过氧化物酶(APX)活性在胁迫第1 d和第1.5 d出现显著降低,‘大师’ APX活性胁迫第0.5 d显著降低,而第1 d显著增加,‘长征’胁迫1.5 d出现显著升高,且3个草地早熟禾品种在胁迫第2 d时APX活性均恢复到胁迫前的水平,与胁迫前相比差异不显著.同工酶表达上,3个草地早熟禾品种的SOD, POD和CAT同工酶表达量变化不显著,GR同工酶表达量减弱,APX同工酶表达量在耐热品种‘热力’中增加,在不耐热品种‘长征’中变化不大.     

不同饲喂水平对肉用绵羊生长性能、屠宰性能及器官指数的影响

本文旨在研究不同饲喂水平对20～35 kg杜寒杂交公羔的生长性能、屠宰性能和器官指数的影响.采用单因素完全随机区组试验设计,将21只平均体重为(19.14±2.37)kg公羔随机分为3组,按照自由采食(AL组)、自由采食量的70％(IR70组)和自由采食量的40％(IR40组)3个水平饲喂,每组7只羊,每只羊为1个重复.当AL组的试验羊体重达到35 kg时进行屠宰试验,测定生长性能、屠宰性能及重要内脏器官的重量和发育情况.试验期66 d.结果表明:不同的饲喂水平对净增重、平均日增重和干物质采食量有显著的影响(P＜0.05),生长性能和部分屠宰指标表现为相同的变化规律,即AL组＞IR70组＞IR40组,3组之间差异显著(P＜0.05);屠宰率、净肉率和胴体净肉率组间无显著性差异(P＞0.05);AL组瘤胃重占复胃总重比例最高,为67.08％,与IR70组差异不显著(P＞0.05);肝脏重占宰前活重比例以AL组最高,显著高于IR70和IR40组(P＜0.05).结果提示,饲喂水平对肉用绵羊生长性能、复胃的重量与发育、主要生理器官的发育具有不同程度的影响;本试验结果与NRC( 2007)肉羊的饲养标准有一定的差距.     

山西黑猪不同器官组织乳酸脱氢酶同工酶活性分析

为了探究哺乳动物中乳酸脱氢酶(LDH)同工酶的种类及不同器官组织中LDH同工酶的活性及相对含量,试验以山西黑猪为试验材料,利用紫外分光光度计和聚丙烯酰胺凝胶电泳对不同器官组织中LDH活性和同工酶谱带进行检测和分离。结果表明:不同器官组织中LDH的活性存在明显区别,不同器官组织中所含LDH同工酶的种类和相对含量各不相同,不同器官组织中相同LDH同工酶的相对迁移率差异不大。说明动物机体中同工酶的保守性较高。     

夏×藏一代羊血清淀粉酶活性及同工酶

对92 只夏洛来与藏羊的杂种一代绵羊的血清淀粉酶活性及其同工酶酶谱进行了研究。结果表明:①夏×藏一代羊的血清淀粉酶(AMY) 有AMY1 ,AMY2 和AMY3 三种同工酶,其中AMY2 同工酶存在多态性; ②AMY2 同工酶有显现酶活性的AMY2A 和不显现酶活性的AMY2O 两种表型,AMY2O型为优势表型(75% ) ;③血清AMY活性为242.3IU/L;④AMY2A型绵羊的血清AMY 活性(305.3IU/L) 非常显著地高于AMY2 O型绵羊(154,1 IU/L)(P< 0.01) 。     

稻草秸秆粗饲料日粮中添加活性酵母对羔羊生长性能及营养物质消化率的影响

为了研究添加活性酵母对以稻草秸秆为粗饲料日粮利用率的影响,本试验将40只羔羊(体重约11.41 kg)随机分为对照组和活性酵母添加组2个处理,开展生长试验和消化试验。试验结果表明:活性酵母添加组羔羊平均日增重比对照组显著提高14.28%(P0.05),饲料转化效率为14.03%,显著高于对照组的12.44%(P0.05)。添加活性酵母显著提高半纤维素的消化率,由对照组的55.6%提高到62.9%(P0.05);日粮干物质、有机物、粗蛋白质、中性洗涤纤维(NDF)及酸性洗涤纤维(ADF)的表观消化率差异不显著(P0.05)。与对照组相比,血浆尿素氮浓度随活性酵母添加量的增加而显著降低(P0.05),血浆葡萄糖及β-羟丁酸等生化指标差异均不显著(P0.05)。综上所述,活性酵母的添加可以提高羔羊对以稻草秸秆为粗饲料的高纤维日粮的利用效率。     

猪血清乳酸脱氢酶与日增重的相关关系

选择新疆瘦肉型猪新品种四世代育种群，长大新，汉普夏，加系大长白等四类群共４９头猪试验，采用电泳法测定血清中乳酸脱氢酶同工酶的相对含量，分析它们与日增重的相关关系。结果表明，７０日龄血清中ＬＤＨ存在有五种同工酶，它们之间相对含量差异显著；７０日龄血清ＬＤＨ１，ＬＤＨ２含量分别与７０－１３０日龄日增重，１３０－１８０日龄日增重之间存在显著正相关；其它型与日增重相关不显著，各同工酶之间也存在有显著或极显     

桑叶超氧物歧化酶（SOD）的研究

分别用高速冷冻离心法和低速室温离心法提取了桐乡青、湖桑１９７、团头荷叶白、尖头荷叶白４个品种的顶芽、第５位和第１０位叶以及蚕沙残桑叶的ＳＯＤ粗酶液，然后用ＮＢＴ光还原法和聚丙烯酰胺凝胶电泳分别分析测定了它们的活性及其同工酶。试验结果表明：用高速冷冻离心法和低速室温离心法提取的ＳＯＤ，其活性无显著差异；同一叶位的桑叶ＳＯＤ活性在不同桑品种之间无显著差异；同一桑品种不同叶位的ＳＯＤ活性有显著差异；蚕沙残桑叶的ＳＯＤ活性与第１０位叶的ＳＯＤ活性相当。发现桑叶中有３～４种ＳＯＤ同工酶。     

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