条带式改良陡坡草地的研究

本文对条带式补播改良陡坡草地的效果进行了研究，结果表明，条带式改良草地可以提高产草量。较天然草地的风干草产量提高１７０．３０％－２２５．６０％（Ｐ＜０．０１），且可以改善草群品质，草群中豆科牧草的比重由原来的２４．０４％增加到７５．４６％，有毒有害植物明显秒。草地植覆盖度由原来的４２．５％提高到８３．５％。改变了植物群落结构，将蒿属植物为建群种的群落变为沙打旺－野艾蒿－万年蓬组成的群落。改良草地地     

条带式改良陡坡草地的研究

对条带式补播改良陡坡草地效果研究的结果表明，条带式改良草地可以提高产草量，较天然草地风干草产量提高１７６．３０％－２２５．７％（Ｐ＜０．０１），且可以改善草群品质，草群中豆科牧草的比重由原来的２４．０４％增加到７５．．４６％，有毒有害植物明显减少。草地植工由原来的４２．５％提高到８３．５％。改变了植物群落结构，将蒿属植物为建群的落变为沙打旺－野艾蒿－万年蓬组成的群落。改良草地地表径流比天然草地减少     

中度退化高寒草甸草地的补播改良研究报告

对中度退化的高寒草甸进行补播改良,其研究的结果表明,人工补播是改良退化草地的一项重要措施。补播的第三年,改良草地产草量比天然草地产草量提高20－30％,草地植被盖度由原来的32．5％提高到56．5％,草群品质改善,草群中可食牧草种类增多,有毒有害植物明显减少。杂草及有毒有害植物为建群种的群落,变为老芒麦－无芒雀麦－披碱草为优势种的群落。由于草地盖度的增加,也减少了土壤冲刷,有效地控制了土壤养分和水分的流失。     

柴达木盆地退耕撂荒地的改良

对柴达木盆地退耕撂荒地进行封育＋灌溉改良试验，结果表明，改良第１、２、３年地上生物量较改良前分别提高６２．１％，１４８．３％，３６９．０％，草群中优良牧草比例由几乎为零上升到６９．３％，群落组成由刺儿菜－苦苣菜－阔叶独行菜为主，演变为芦苇－星星草－刺儿菜为主，植物种类由改良前的４科４种增加到６科１２种，植被盖度由１５％上升到９０％，生态和经济效益明显。     

高寒地区退化草地改良试验研究

为改善草地植物生存条件,对退化草地进行了改良试验研究,结果表明,３种改良方法都能改善草地生境,增中土壤速效养分。以施肥效果最佳,增加了牧草在草群中比重。禾本科、豆科和莎草科牧草分别比对照区增加９．０２－１０．１７％、１８．４０－２７．７６％和－６．７５％－１．８７％; 柯食牧草增加１倍;围栏封育草地效果次之,禾本科和豆科牧草在草群中所占比重分别比对照区增加２６．８１－３９．８５％和２０．７４－３７     

高寒地区退化草地改良试验研究

高寒草地是我国重要的草地资源，素有“高原肉库”之美称，但由于近年来草地利用不合理，家畜载为量过大，草地出现不程度退化，为改善草地植物生存条件，对退化草地进行了改良试验研究，结果表明，３种改良措施可改善草地生境，增加土壤速效养分，施肥改良效果最佳，增加牧草在草群中所占比重，禾本科，豆科和莎草科牧划分别对对照区增加９．０２％～１０．１７％，１８．４０％～２７．７６％和－６．５７％～１．８７％，可食３９     

内蒙古白音锡勒地区天然割草场改良措施的研究

天然草场每公顷施尿素１１２．５公斤，群落生物量平均增产９４．２３％，其中禾草增产幅度较大。施用Ｎ肥还可以提高草地质量。深耙松土１０ｃｍ左右，当年可以增产３０．８７％，第二年增产１０．１２％，羊草的生物量和密度明显增加。６月下旬喷施浓度为１０００－１５００ｐｐｍ的硝酸稀土溶液，平均增产１１．８７％，这些改良措施均有一定的经济和生态效益。     

高寒地区退化草地改良试验研究

对退化草地进行改良试验研究的结果表明,施肥改良效果最佳。增加优良牧 草群中所占比例,禾本科、豆科和莎草科牧草分别比对照区增加９．０２－１０．１７％,１８．４０－２２．７６％和－６．５７－１．８７％,可食牧草增产１倍;围栏封育草地效果次之,禾本科和豆科牧草在草群中所占比重分别比对照区增长２６．８１－３９．８５％和２０．７４－３７．８５％,莎草科牧草比例下降１１．８５％－１９．２３％,可食牧草增产１倍     

伊犁绢蒿在荒漠草原补播的效果分析

为了更加科学地评价乌鲁木齐市天然草原补播效益,笔者通过分析大量的实地调查数据,得出结论:补播改良措施可使草群结构发生改变,促进优良牧草的生长,表现为生物量显著提高,草群高度、盖度明显增加,退化草地群落逐渐向良性方向发展。     

根茎禾草盐湿草甸松土改良效果的试验研究

1984－1989年在乌盟察右前旗煤夭乡羊草一碱茅十杂类草盐湿草甸围栏草场上，进行的松土改良，试验结果表明，草场经松土改良后，第二及第三年土壤容重降低10．46－13．07％，孔隙度和含水率则分别增加6．04－7．55％5．48－10．55％，草场生境条件的改善，使草群高度，盖度加大，质量得到提高，亩产鲜草增加176公斤，提高草场产量42．67－163．69％，经济效益较为显著，实属一项改良盐湿草甸草场的有效措施。     

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.     

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     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

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

Tropical Animal Health and Production -