高寒牧区沙化草地治理草种——硬秆仲彬草开花习性观察

对硬秆仲彬草（Kengyilia rigidula）的开花习性进行了观测,结果表明：小花最先从穗的中部开始开放,然后逐渐向上下扩展开放。小穗上最靠近外颖的第1朵小花最先开放,位于小穗最顶部的小花通常不育。小花集中在白天开放．下午13：00～17：00时为开花高峰期。单个花序开花持续时间为14～16天,群体开花时间可达到30天左右。     

高寒牧区沙化草地治理草种——硬秆仲彬草开花习性观察

对硬秆仲彬草(Kengyilia rigidul)a的开花习性进行了观测,结果表明:小花最先从穗的中部开始开放,然后逐渐向上下扩展开放。小穗上最靠近外颖的第1朵小花最先开放,位于小穗最顶部的小花通常不育。小花集中在白天开放,下午13∶00~17∶00时为开花高峰期。单个花序开花持续时间为14~16天,群体开花时间可达到30天左右。     

热研二号柱花草开花习性的观察

在田间栽培条件下，热研二号柱花草一般９月下旬开始开花，花期持续３个月，花序与花朵的开花顺序与分化形成的先后一致，每朵小花只开放一次，以下午９：３０开放率最高，小花开放两小半小时，１２时闭花，２０～３０天子房发育的种趋于成熟。     

苜蓿的开花习性及其杂交技术的研究

对苜蓿开花习性的研究结果表明，每个花序上的小花由下向上开放，从第一朵花开放到最后一朵花开完需４～７天，小花均在白天８时左右开始开放，１０～１４时达开花高峰，立秋前，后分别于２０、１８时停止开放，苜蓿是一种自然杂交率很高的植物，在自然条件下主要靠昆虫传粉进行异花授粉繁殖后代，人工去雄宜在花蕾发育至第３时期进行，去雄后速套袋隔离，过１～２天的８～１４时进行授粉可保证获得真正的杂交种。     

纳罗克非洲狗尾草的开花习性

纳罗克非洲狗尾草小花开放顺序通常从中上部向基部逐渐开放,最上部小花最后开放;一日开花高峰在清晨3～4时,单个花序开放持续时间26～57d,平均42.5d;逐日开花高峰出现在开花第10～15d;前25d开花数占总数的90%;阴雨天将严重影响小花开放.     

高寒藏区巴青1号青稞开花习性的研究

研究表明:巴青1号青稞在青海高寒地区种植,大部分在抽穗之后开花,小花开放顺序通常由中部向上下两端开放,单个花序开花持续时间为5~8d,群体开花时间可达到10d。一日开花高峰在上午09~11时和下午13~15时。青稞开花的适宜温度为17.2℃~22.6℃,相对湿度55%~65%,结实率为85.7%。     

少花蒺藜草开花习性与种子萌发特性研究

通过对少花蒺藜草小穗结构与分布、小花开花习性的观测表明:少花蒺藜草是雄花两性花植物,每小穗由两朵小花构成,第一朵小花是两性花,第二小花是雄性花.自花传粉是其主要的授粉方式,小花沿着穗顶部依次向下开放,具有2个小穗的刺苞在穗部所占比例为61.88%.种子的生长部位和大小影响其发芽率、平均发芽速度.去除刺苞中成熟较晚的小穗可提高成熟较早的小穗中种子的发芽率,而去除刺苞中成熟较早的小穗不会影响成熟较晚的种子的发芽率,但种子变成狭长形.     

桑蓟马在桑枝上的分布规律及其天敌的调查

根据对桑枝上桑蓟马虫口密度的调查，明确其分布主要集中在桑枝０－８叶位上，随着秋季桑枝止心及树势变弱，最高虫叶位上升到０－４位。通过田间调查，桑蓟马的主要天敌有：大草蛉、中华草蛉、南方小花蝽、中华筒管蓟马、塔六点蓟马等多种。     

小花位置对老芒麦和诺丹冰草种子质量的影响

对老芒麦Elymus sibilicus和诺丹冰草Agropyron desertorum穗上不同位置种子的百粒重及萌发特性进行了研究.结果表明,种子的重量与单花开花到收获所经历的时间长短有关,开花越早的小花所结种子越重.由于老芒麦种子发育时间较短,由小花位置造成的种子大小的差异较明显.小穗及小花位置亦影响到种子的萌发力,老芒麦中越重的种子萌发力越高,而诺丹冰草种子的发芽率与种子重量呈负相关,表明诺丹冰草种子的休眠性与种子的成熟度有关.     

老芒麦、诺丹冰草结实特性的研究

对老芒麦Elymus sibilicus和诺丹冰草Agropyron desertorum的结实特性进行了调查研究.结果表明,各穗之间结实率的变化较大;小穗上各小花位置的结实是随机的,最顶部的可育小花结实率明显低于其基部小花.每穗中部所结种子重于顶部和基部种子,基部种子最轻.对每小穗而言,基部小花所结种子最重,由基部向顶部种子质量逐渐递减.种子质量的变化与穗部开花顺序表现出一致性.     

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.     

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.     

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     

Evaluation of the Microbiological Status of Milk and Various Structures in Mammary Glands from Naturally Infected Dairy Cows

A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.     

Development and survival of free-living stages of gastrointestinal nematodes of sheep and goats on pasture in the Nigerian derived savanna

Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L₃) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L₃ developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.