聚乙二醇对羊茅属4种植物种子萌发特性的影响研究

用不同浓度聚乙二醇(PEG)溶液作为渗透胁迫剂,对羊茅属Festuca 4种牧草种子的萌发情况进行了研究.结果表明,低PEG浓度(5%)促进中华羊茅F.sinensis和西北羊茅F.kryloviana胚根的生长,较高PEG浓度(10%～15%)显著抑制4种羊茅植物胚根和胚芽的生长及种子发芽率、发芽势、发芽指数和活力指数的提高,PEG浓度对胚芽生长的抑制效应比胚根大.各植物胚根(芽)长、发芽率、发芽势、发芽指数和活力指数均随PEG浓度的增加呈显著降低变化(P＜0.05).胚根/胚芽比、发芽率、发芽势可作为羊茅属牧草种子萌发期抗旱性初步评定的鉴定指标.4种植物的抗旱性顺序为中华羊茅＞西北羊茅＞毛稃羊茅F.kirilovii和法恩苇状羊茅F.arundincea.     

新疆狗牙根种质芽期耐盐性综合评价

为了解不同狗牙根种质在芽期耐盐差异程度,采用常规纸上萌发法,研究不同NaCl浓度(0、0.4%、0.8%、1.2%、1.6%)对来源于新疆不同生境下50份狗牙根种质相对发芽率、相对发芽势、发芽指数、胚根长、胚芽长的影响,并通过聚类分析法对其耐盐性进行综合评价。结果表明,随盐胁迫增加,狗牙根种质相对发芽率、相对发芽势、发芽指数呈明显降低趋势,而胚根长、胚芽长则呈先升后降趋势,0.4%盐胁迫下达到最高;各测试指标变异系数呈逐渐加大趋势,至1.6%盐胁迫时其变异系数均较对照增加2.0倍以上。新疆狗牙根半致死NaCl浓度(S_50%)均值为1.28%,变异系数为45.66%,且1.2%NaCl可作为其耐盐鉴定最适浓度。聚类分析综合表明,50份新疆狗牙根种质中表现较稳定的耐盐种质为Cd012,中度耐盐种质为Cd019、Cd021、Cd020、Cd054,敏盐种质为Cd001、Cd033、Cd035、Cd057、Cd059。     

PEG模拟干旱胁迫下29份偃麦草种质种子萌发期抗旱性评价

以20%聚乙二醇溶液(PEG-6000)为渗透介质模拟干旱胁迫条件,对29份偃麦草种质资源进行了种子萌发期抗旱性评价。结果表明:PEG胁迫降低了偃麦草种质资源的发芽率、发芽势、发芽指数、活力指数,抑制了胚芽和胚根的生长发育。以相对发芽率、相对胚根长、相对胚芽长、萌发抗旱指数、胁迫指数、相对发芽势及相对活力指数为依据,通过隶属函数法综合评价认为,29份偃麦草种质资源的抗旱性顺序依次为:E39E14E11E13E16E03E07E25E34E42E09E29E17E31E21E26E06E10E12E27E38E08E01E04E41E19E37E02E24。     

PEG-6000模拟干旱胁迫对黄芪属种子萌发的影响

为了筛选出抗旱性较强的黄芪属种质材料,试验利用不同浓度(5%、10%、15%、20%)的聚乙二醇(polyethylene, PEG-6000)对6种黄芪(紫花沙打旺、中沙1号沙打旺、春疆1号沙打旺、沙打旺、斜茎黄芪、黄芪草,按1～6编号)的种子进行模拟干旱胁迫发芽试验,以不加PEG-6000的纯化水为对照,测定不同干旱胁迫处理下种子萌发的根长、胚芽长,计算发芽率、发芽势、发芽指数、活力指数、相对发芽率、相对发芽势、相对发芽指数、相对活力指数、根芽比、相对芽长、相对根长11项指标,采用模糊数学隶属函数法进行综合评价。结果表明：不同浓度PEG-6000胁迫下同一品种种子萌发情况不同,1号(紫花沙打旺)在5%、10%和20%浓度PEG-6000胁迫下发芽率、发芽势、发芽指数和活力指数均高于对照,6号(黄芪草)在15%浓度PEG-6000胁迫下发芽率、相对根长和根芽比均高于对照,对种子萌发有促进作用;2号(中沙1号沙打旺)和5号(斜茎黄芪)在各浓度PEG-6000胁迫下发芽势、发芽指数和活力指数均低于对照,种子萌发受到抑制;3号(春疆1号沙打旺)和4号(沙打旺)在各浓度PEG-6000胁迫下...     

PEG-6000干旱胁迫下15个苜蓿品种种子萌发抗旱性评价

为了筛选出适宜科尔沁半干旱地区种植的抗旱性强的苜蓿品种,试验以15个苜蓿品种为材料,采用浓度为15%的聚乙二醇(PEG-6000)溶液模拟干旱胁迫条件,测定了干旱胁迫与非干旱条件下15个苜蓿品种种子萌发期的根长、芽长,计算根芽比、发芽率、发芽势、发芽指数等指标并进行了综合评价。结果表明:15%的PEG-6000溶液对苜蓿的发芽率、发芽势、发芽指数、根芽比都有一定的抑制作用,其中对发芽势和发芽指数抑制作用较大;15%PEG-6000胁迫下苜蓿的发芽率与发芽指数间存在极显著正相关(P0.01),发芽势与发芽指数间存在显著正相关(P0.05),芽长与根芽比间存在极显著负相关(P0.01);15个苜蓿品种的抗旱性强弱为威神骑士T英斯特敖汉苜蓿巨能MT 3015农菁8号32 IQ公农1号北极熊挑战者乐寒Dryland宁苜1号黄花苜蓿Spyder。说明威神、骑士T、英斯特的抗旱性较强,适宜在科尔沁半干旱地区种植。     

鸭茅种子萌发对渗透胁迫响应与耐旱性评价

根据不同鸭茅(Dactylis glomerataL.)品种萌发期对干旱胁迫的响应,评价9份南方主推鸭茅种质材料抗旱性差异,为其耐旱胁迫人工调控提供依据.PEG(PEG-6000)模拟干旱胁迫条件,分别以5％,10％和13％(-0.1MPa,-0.2 MPa和-0.3 MPa)聚乙二醇溶液作渗透介质,采用人工气候箱内培养皿培养进行萌发期抗旱性研究,测定萌发抗旱指数、活力抗旱指数、相对发芽率、相对发芽势、相对胚芽长(干重)和相对胚根长(干重)6个指标,应用模糊隶属函数法进行耐旱性综合评价,并结合种子萌发期贮藏物质转运率与萌发抗旱指数相关性分析进行.结果表明:9个鸭茅材料耐旱隶属函数平均值范围为0.139～0.935.宝兴平均值最高,为0.935,其耐旱性最高,其次为02-116和斯巴达,平均值分别为0.883和0.824,而01998材料平均值最低,为0.139.胚根、胚芽在不同渗透胁迫条件下生长受到不同程度的抑制,贮藏物质转运效率降低,胚根、胚芽干重和贮藏物质与萌发抗旱指数相关性显著.13％PEG渗透溶液浓度胁迫处理8d可作为研究鸭茅萌芽期抗旱性鉴定的水分胁迫适宜浓度.因此,采用模糊隶属法进行鸭茅耐旱性的综合评价时,贮藏物质转运效率可作为萌芽期抗旱性鉴定的重要指标.     

4个紫花苜蓿品种萌发期抗旱性比较

为对比甘肃广泛种植的4个紫花苜蓿品种(甘农1号、新疆大叶苜蓿、中苜1号和中天1号)萌发期的抗旱性,采用不同浓度聚乙二醇6000(Polyethylene glycol 6000,PEG-6000)模拟干旱胁迫的方法,测定4个紫花苜蓿品种的种子在干旱胁迫下的发芽势、发芽率、发芽指数、抗旱指数和根芽比,并用隶属函数法对4个紫花苜蓿品种的萌发期抗旱性进行综合评价.结果表明:4个紫花苜蓿品种的种子的发芽势、发芽率和发芽指数在各个PEG浓度下均为新疆大叶苜蓿最大,根芽比和抗旱指数为甘农1号最大;随胁迫程度的加剧4个紫花苜蓿品种的种子的发芽势、发芽率、发芽指数和抗旱指数均呈下降趋势,而根芽比先升高后降低:PEG浓度为5％ 时最大,分别为甘农1号6.91、新疆大叶苜蓿3.68、中苜1号4.54和中天1号6.04,0％ 时次之;与PEG浓度为0％ 时相比,PEG浓度为5％ 时,中天1号的发芽势和发芽指数下降幅度最大,PEG浓度为25％ 时,新疆大叶苜蓿的发芽率和中天1号的抗旱指数下降幅度最大.萌发期综合抗旱性为甘农1号>中苜1号>新疆大叶苜蓿>中天1号.     

模拟干旱条件下不同苜蓿种质材料萌发期抗旱性评价

选取6份苜蓿种质材料,在0、-0.06、-0.17、-0.53MPa的渗透势条件下进行发芽实验,研究PEG-6000模拟干旱处理对不同苜蓿材料种子萌发的影响。结果表明,随着PEG溶液浓度增大,不同苜蓿材料受胁迫程度增大,其相对发芽率、相对发芽势、相对发芽指数、相对活力指数、种子相对胚根长及胚芽长均呈降低趋势。隶属函数法综合评价得到的6份苜蓿材料的抗旱性排序为:中苜2号=伊犁苜蓿>公农2号>扶风苜蓿>草原3号>赛特。     

不同糜子品种萌发期对干旱胁迫的响应及抗旱性评价

利用PEG-6000溶液模拟干旱胁迫,对16个糜子(Panicum miliaceum L.)品种萌发期与抗旱性相关的指标进行测定,比较其抗旱性,并采用隶属函数法对其抗旱性进行综合评价.结果表明:不同糜子品种抗旱性有显著性差异.干旱胁迫抑制糜子种子萌发活力,降低了萌发速度和发芽率;干旱胁迫对糜子胚根的抑制要强于胚芽;萌发抗旱指数、相对发芽率、相对发芽势、相对胚芽长、相对胚根长、相对萌发指数和相对活力指数均可作为糜子萌发期抗旱性鉴定的参考指标.河曲红黍子、伊选红糜、粘丰5号这3个品种抗旱性较强.     

34份狼尾草萌发期抗旱性综合评价

为评价狼尾草抗旱能力,筛选优异资源,以34份狼尾草材料为对象,研究其PEG-6000胁迫下种子发芽特性,采用隶属函数法和聚类分析对狼尾草抗旱性进行综合评价。结果表明,5%的PEG-6000浓度处理下,狼尾草的发芽率、萌发指数、发芽指数较对照显著增加,表现为促进效应;随着干旱胁迫的增加,各材料发芽受抑作用明显。狼尾草胚芽长和胚根长随PEG浓度的增加呈逐渐下降趋势,其中胚芽较胚根对干旱更敏感。依据测定指标差异程度和变异系数,表明15%的PEG-6000是狼尾草萌发期抗旱性鉴定的适宜浓度。在此浓度处理下,34份狼尾草综合评价值在0.027～0.942之间,其中LW31最高,LW29最低。通过聚类分析所有材料被分为3类,其中LW4、LW9、LW11、LW31、LW42、LW20-2和LW21-1属抗旱材料,可作为狼尾草抗旱性新品种选育的基础材料。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

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

Tropical Animal Health and Production -     

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.     

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.     

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.     

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.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

Changes in proportion of canine urinary calculi composed of calcium oxalate or struvite in specimens analyzed from 1981 through 2001

The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.