几对桑蚕新品种耐氟性的比较

以氟敏指数为耐氟性指标,通过对夏7×夏6、秋菊×新6、春华×秋实、秋丰×白玉、丰一×54A、菁松×皓月6对蚕品种的耐氟性比较,结果表明夏7×夏6耐氟性最强,秋丰×白玉、秋菊×新6耐氟性次之,丰一×54A耐氟性较强,春华×秋实耐氟性较弱,菁松×皓月耐氟性最弱。     

春用家蚕新品种华·东×春·晨的育成

采用幼虫4龄期人工添食20 mg/kg氟化纳溶液定向选择耐氟污染性能和杂交育种、回交改良等育种技术,育成了具有耐氟污染特性的春用多丝量家蚕新品种华·东×春·晨。该品种在浙江省家蚕新品种实验室共同鉴定和农村生产试验鉴定中,表现出体质强健、耐氟性好、产茧量高、茧型大、丝质优等特点,其中氟敏指数检测数据显示其耐氟性能明显强于春用品种菁松×皓月,并达到了秋用耐氟污染品种秋丰×白玉的水平。新品种在农村生产试验鉴定中,产茧量及丝质成绩普遍优于当地对照品种菁松×皓月和秋丰×白玉,特别是盒种产茧量分别超过对照品种菁松×皓月和秋丰×白玉7%、12%左右。2010年2月该品种已通过浙江省农作物品种审定委员会审定,适合在浙江省及长江中下游蚕区特别是氟化物污染较严重的蚕区春期推广饲养。     

桑蚕新品种华秋×松白耐氟性的测定

笔者通过对华秋×松白、菁松×皓月、秋丰×白玉3对蚕品种的耐氟性测定 ,计算其氟敏指数 ,结果表明桑蚕新品种华秋×松白的耐氟性与秋用品种秋丰×白玉处在相同的耐氟性水平上 ,耐氟性能较高 ,极明显强于春用品种菁松×皓月     

浙江省现行蚕品种耐氟性比较试验

采用添氟对若干桑蚕现行一代杂交种进行耐性比较试验,结果认为不同杂交种对氟的耐受力差展很大,夏秋蚕品种的耐氟性显著高于春用种。在测试品种中,耐氟性排序为：秋丰×白玉〉丰１×５４≌华峰×雪松≌薪杭×科明〉春蕾×菁松×皓月≌浙蕾×春晓。     

繁育夏秋用品种秋丰、白玉的体会

<正>秋丰、白玉是中国农科院蚕业研究所采用多品种杂交方法育成的一对夏秋用品种,该品种于1989年通过浙江省和国家新蚕品种的审定.秋丰×白玉有好养、张产较高、丝质优良、耐氟性强的特点,适宜于夏秋期尤其是中晚秋期饲养受到农村和丝厂的欢迎,我省武进、丹阳及江阴市蚕区饲养后反映较好.据了解,因该品种耐氟性好、茧形大、产量高,浙江省一些氟污染严重而春用品种饲养不好的蚕区用作春期饲养效果较显著,张产量、张产值均较春用品种提高20—30%.本场从1993年春开始至今已繁育了3期12个对交批,通过近几年繁育,我们对这对品种有以下一些认识和体会.     

春秋兼用抗氟品种华峰×雪松育成初报

本文介绍了春秋兼用抗氟蚕品种华峰×雪松的鉴定成绩。该品种体质强,具有一定的抗氟中毒能力和耐高温性,孵化好,容易饲养,产茧量高,茧层厚,产值高,丝质较优,产卵多,制种容易,具有发展前途。     

春秋兼用耐氟蚕品种华峰_(GW)×雪·A的选配

采用系统分离法建立了华峰灰、白蛾系 ;以华峰、雪松为基础 ,选择耐氟性强、茧丝质优良的现行品种组配若干多元杂交组合 ,通过实验室常规鉴定和耐氟性能测试 ,筛选出耐氟性能好、茧丝质优的家蚕三元杂交组合华峰GW×雪·A。 4省区联合鉴定和种场试繁表明 ,该组合各项经济性状都达到了菁松×皓月的水平 ,繁育性能比华峰×雪松有较大的改善 ,在氟化物污染较严重的蚕区饲养能正常生长发育 ,获得高产     

现行蚕品种对氟化物的抗性研究

本文对现行一代交杂种及其原种进行了对氟化物的抗性研究。在供试的9个一代交杂种中丰-×54A、秋丰×白玉属强抗品种,其二～三龄的耐氟量为40～50ppm;7532×75新、浙农1×苏12属中抗品种,耐氟量为30～40ppm;中新1×日新1、苏3·秋3×苏4属弱抗品种,耐氟量为30ppm;钟秋×金铃、春蕾×镇珠、苏5×苏6属敏感品种,耐氟量在30ppm以下。在供试的14个原蚕品种中75新属强抗品种,其二～三龄的耐氟量为40～50ppm;7532、日新1、苏4、46属中抗品种,耐氟量为30～40ppm;57A、苏3·秋3、中新1属弱抗品种,耐氟量在30ppm以下;苏3、秋3、24、57B、苏5、苏6属敏感品种,耐氟量为20～25ppm。     

桑蚕新品种华·秋×松·白性状

华·秋×松·白是湖州蚕桑科学研究所采用引进、组配、筛选系统分离育种方法 ,历经１０年育成的夏秋蚕新品种。１９９８～１９９９年参加浙江省实验室联合鉴定 ,表现出产茧量高、茧丝质优、且耐氟性强 ,容易饲养 ,孵化、眠起、老熟齐一。经省农作物品审委蚕桑专业组讨论同意 ,提前于１９９９～２０００年参加浙江省农村生产鉴定 ,盒种产茧量、盒种产值、解舒丝长、纤度、净度、综合经济性状优良 ,符合审定标准 ,于２００１年４月通过浙江省农作物品种审定委员会审定。适合长江流域及同等条件地区饲养 ,尤其在氟污染地区 ,春期饲养耐氟性较好…     

苏菊×明虎与秋丰×白玉的耐氟性测定

2002年秋期对江浙地区发种量最大的苏菊×明虎、秋丰×白玉二对主要夏秋用品种进行了耐氟能力的测定,测定方法采用氟敏指数法,测定结果:秋丰×白玉正、反交的耐氟性强于苏菊×明虎正、反交,尤其在200mg/kgNaF溶液浓度添食时,这种表现更为明显。     

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