11份无芒雀麦苗期耐盐性评价

对11份引自俄罗斯的野生无芒雀麦(Bromus inermis Leyss.)材料,在0.3%、0.4%、0.5%NaCl胁迫下,通过存活率、总生物量、叶片伤害率、株高的测定,采用隶属函数法和标准差系数赋予权重法进行耐盐性综合评价。结果表明:供试11份无芒雀麦在0.3%、0.4%、0.5%NaCl胁迫下存活率分别为90%～100%,76.7%～96.7%,67.0%～96.7%;根据耐盐性综合评价值(D)得出供试材料耐盐性顺序为,ZXY04P-371>ZXY04P-255>ZXY04P-136>ZXY04P-188>ZXY04P-96>ZXY04P-503>ZXY04P-34>ZXY04P-322>ZXY04P-241>ZXY04P-46>ZXY04P-18。     

21份偃麦草属牧草苗期耐盐性评价

对21份国外引进的野生偃麦草属种质材料在不同梯度NaCl胁迫下,通过存活率、株高、根茎比、生长胁迫指数和叶片伤害率的测定,利用主成分分析法和隶属函数法,综合评价其耐盐性.结果表明:随着盐浓度增大,偃麦草属材料除伤害率外,其它指标与对照相比均有所下降.根据综合评价值可知,其耐盐性由强到弱为ZXY03P-388,ZXY03P-349,ZXY03P-433,ZXY04P-210,ZXY04P-257,ZXY04P-77,ZXY03P-463,ZXY03P-480,ZXY04P-25,ZXY03P-368,ZXY03P-491,ZXY04P-176,ZXY04P-29,ZXY04P-490,ZXY04P-6,ZXY03P-444,ZXY04P-103,ZXY03P-318,ZXY03P-271,ZXY03P-289,ZXY04P-157.     

猫尾草属牧草苗期耐盐性评价

对16份引自俄罗斯的野生猫尾草属(Phleum pratense)材料,在0.3%,0.4%和0.5%NaCl胁迫下,通过株高、存活率、叶片伤害率的测定,采用隶属函数法和标准差系数赋予权重法进行耐盐性综合评价。结果表明:供试16份猫尾草属牧草在0.3%,0.4%和0.5%NaCl胁迫下存活率分别为30%~83%,13%~67%和7%~57%。根据耐盐性综合评价值(D)得出猫尾草耐盐性顺序,ZXY03P-465>ZXY03P-168>ZXY03P-149>ZXY03P-389>ZXY03P-117>ZXY03P-81>ZXY03P-240>ZXY03P-370>ZXY03P-290>ZXY03P-64>ZXY03P-17>ZXY03P-340>ZXY03P-135>ZXY03P-186>ZXY03P-419>ZXY03P-33。     

NaCl盐胁迫对苗期燕麦的耐盐性鉴定及综合评价

分别在0、0．2％、0．4％、0．6％、0．8％、1．0％、1．2％的NaCl浓度下胁迫坝莜1号、白燕2号、白燕6号、白燕7号4份种质材料,测定了在盐胁迫下苗期燕麦的存活率、株高、根长、根数,进而综合评价供试材料耐盐性的强弱。结果表明：苗期燕麦在NaCl浓度0．2％～0．6％的胁迫下,均属中等耐盐牧草;各供试材料间耐盐性差异显著,其中自燕6号综合评价值为0．9679,耐盐性最强;坝莜1号综合评价值分别为0．5000,耐盐性最差。     

偃麦草属植物苗期耐盐性指标筛选及综合评价

对10份自国外引进的野生偃麦草属种质材料在不同梯度NaCl胁迫下,测定存活率、K /Na 、丙二醛含量、脯氨酸含量等12项指标,进行相关分析、主成分分析、隶属函数法和通径分析。结果表明,1)筛选出存活率、K /Na 、丙二醛含量、脯氨酸含量、生长胁迫指数、相对生长速度6个可以对偃麦草属植物耐盐性进行评价的指标;2)根据耐盐综合评价值(D)得出材料耐盐性排序为ZXY04P-6>ZXY04P-210>ZXY04P-29>ZXY04P-490>ZXY04P-176>ZXY04P-103>ZXY03P-271>ZXY04P-157>ZXY03P-444>ZXY03P-289;3)10个材料的耐盐性预测值(VP)与综合评价值(D)极显著相关。     

20份无芒雀麦种质材料苗期抗旱性综合评价及光合特性分析

在温室条件下,采用反复干旱法,对引进的20份无芒雀麦(Bromus inermis Leyss.)种质材料,以存活率、株高、绿叶数、地上生物量、地下生物量和根冠比6个指标的抗旱系数值,采用聚类分析法、标准差系数赋予权重法进行综合评价。结果表明:20份无芒雀麦苗期抗旱性划分成3个级别,其中抗旱性较强的有9份材料,抗旱性较弱有6份材料,抗旱性居中的有5份材料。20份无芒雀麦种质材料苗期抗旱性排序结果为ZXY06P-1621抗旱性最强,ZXY05P-1171最弱。不同抗旱级别种质材料的光合特性表现为:随着持续干旱胁迫延续,其光合速率(P_n)、蒸腾速率(T_r)和气孔导度(G_s)均呈下降趋势,复水后迅速上升;而CO₂浓度的变化趋势则呈相反变化趋势,且在整个胁迫过程中变化差异不显著。干旱胁迫下抗旱性强的材料能够保持较高的光合性能。     

39份无芒雀麦种质材料苗期抗旱性综合评价

在温室条件下,采用反复干旱法,通过对国外引进的39份无芒雀麦(Bromus inermis)种质材料苗期的存活率、株高、绿叶数、地上生物量、地下生物量、根冠比等指标的测定,进行苗期抗旱性的综合评价。结果表明,39份材料按照抗旱性能强弱划分为3个级别,抗旱性强的有16个材料,抗旱性中等的有16个材料,抗旱性弱的有7个材料,并用标准差系数赋予权重法求得综合评价D值,将各材料抗旱性能进行排序,其中ZXY05P-0854苗期抗旱性最强,ZXY05P-1135最弱。     

PEG渗透胁迫下鸭茅种子萌发特性及抗旱性鉴定

以20%聚乙二醇溶液(PEG-6000)作渗透介质,人工模拟干旱条件,对20份野生鸭茅(Dactylis glomerata L.)种质进行了萌发期抗旱性研究.结果表明:PEG胁迫降低了鸭茅种质的发芽势和发芽率,阻碍了胚芽和胚根的生长,种质间表现出较大差异.运用隶属函数法综合评价20份种质的抗旱性强弱依次为:ZXY04P-148＞ ZXY04P-239＞ ZXY04P-189＞ ZXY03P-69＞ ZXY03P-22＞ ZXY04P-89＞ ZXY04P-22＞ ZXY04P-226＞ ZXY03P-191＞ ZXY03P-173＞ ZXY04P-207＞ ZXY04P-101＞ ZXY04P-75＞ ZXY04P-155＞ ZXY04P-4＞ ZXY03P-227＞ ZXY04P-57＞ ZXY03P-122＞ ZXY04P-136＞ ZXY04P-201.     

Na2CO3胁迫对牧草苗期生长的影响

测定了Na2CO3胁迫下五种禾本科牧草苗期的植株存活率、生物量、生长胁迫指数等生长指标与其耐盐性的关系。结果表明：五种牧草的存活率(浓度＞0．5％)、鲜重与干重均随着Na2CO3胁迫浓度的升高而降低，草种间耐盐性差异显著，其耐盐性强弱顺序是野大麦＞披碱草＞肥披碱草＞老芒麦＞无芒雀麦。     

66份白三叶种质资源萌发期 耐盐性综合评价

本研究对经过0和50mmol·L-1 NaCl处理的66份白三叶(Trifolium repens)种质资源进行发芽试验,旨在评价66份白三叶种质资源萌发期的耐盐性。结果表明,66份参试白三叶材料各指标性状存在差异,盐胁迫对白三叶种子萌发和根系生长均有不同程度的抑制作用,种质间差异较大。通过指标相关性分析和主成分分析,筛选出耐盐性评价指标为相对活力指数和相对发芽率,两项指标权重分别为0.849和0.151。用加权隶属函数法对66份白三叶材料萌发期的耐盐性进行综合评价,耐盐性位居前十位的种质依次是CF022540CF022469CF022538CF022541惠亚ZXY06P-2659CF022543CF022470CF022508CF022466,除惠亚来源于新西兰外,其他材料均来源于俄罗斯。     

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