781五眠蚕下一代眠性及经济性状调查初报

<正> 1998年春季,我省部份蚕种场饲育的781原种在稚蚕期发生小蚕,引起我们的注意。从本场吉安乡五村原蚕区收集了一户蚕农饲育781选出的小蚕,小蚕的体色正常无病态,经过单独饲养观察,结果小蚕全部是眠性变化了的五眠蚕。进一步调查发现该户饲     

五龄蚕起眠到饷食时间长短对其摄食量与经济性状的影响

为了进一步探讨不同饷食时刻对蚕儿产茧效应的影响 ,以同一箔蚕为材料 ,分别在五龄起眠后 2 h、4 h、6 h……饷食 ,调查饷食后 1 8h小时内食下量及近似消化量 ;饲育老熟后调查有关成绩。结果表明 ,起蚕过迟饷食其产量低 ,茧质差。综合各项成绩 ,以五龄起眠后 1 0～ 2 0 h为最适宜的饷食期     

射阳县2005年晚秋蚕暴发蚕病的原因及防治对策

射阳县2005年全县共饲养晚秋蚕36 870张,9月13日出库,9月24日收蚁,而晚秋蚕较之往年相比具有多病齐发、暴发时间提前的特点,发病之重为多年少见。如特佣、盘湾等重点乡镇,一眠醒后已有脓病发生,20%~30%的农户发生黑尾病,而僵病则非常普遍。为此,县技术指导部门及时采取了多项果断措施,成功地遏制了病情的蔓延,减少了蚕农的损失。1原因分析1·1恶劣的气候条件是蚕病暴发的主要原因2005年晚秋蚕期恰逢持续阴雨寡照的灾害天气,9月份在遭遇麦莎、龙王等台风袭击产生强降雨之后,至10月8日前,没有一个完整的晴天,四眠以前气温比往年明显偏低,四龄…     

晚秋蚕血液型脓病严重发生的原因及防治对策

在２００１年的晚秋小蚕期饲养期间 ,我县养蚕血液型脓病发生面广量大且发生时间早 ,最早在头眠就有 ,全县大约有３０%蚕种都有不同程度的发生 ,比去年同比增加了近１０ % ,有的甚至于颗粒无收 ,严重地挫伤了蚕农的养蚕积极性。后由于气象条件的好转和及时的布置落实消毒防病措施 ,才有效地控制住了病情。促进了晚秋蚕生产的顺利进行。为了防患于未然 ,根据今年实际 ,现对晚秋期血液型脓病的发生原因、防治技术作了以下阐述。１原因分析１．１气候条件不理想晚秋蚕从发种以后开始 ,室温一直偏低 ,小蚕期日中室温在２１℃以下 ,远远低于晚秋…     

晚秋蚕不结茧的调查与启示

江苏省射阳县洋马镇现有桑园２２０ｈｍ２,年饲养蚕种近万张 ,是该县重点蚕桑基地乡镇之一。２００１年１０月２０日 ,正值晚秋蚕５龄期 ,该镇港中村近６０００张蚕种出现不结茧蚕 ,约占洋马镇饲养总量的１５% ,其发生规模及损失严重程度为历史所罕见 ,一时蚕农反映强烈 ,不少业内人士也感愕然。鉴此 ,我站迅即派员会同盐城市蚕桑站赶赴洋马镇实地调查 ,为切实保护蚕农利益和慎重行事 ,并邀请中国农业科学院蚕业研究所、省蚕种产品质量鉴定委员会的专家组成调查鉴定小组 ,展开细致缜密的调查 ,最终确认发生大量不结茧蚕和薄皮茧 ,是由多种因…     

重点蚕区秋季传染性蚕病的发生与防治

传染性蚕病的发生与蔓延已成为阻碍重点蚕区蚕桑生产健康发展的障碍之一，本文以我县蚕桑重点乡镇特庸镇为例，就其发生与防治谈一点看法。特庸镇现有桑园１．５万亩，年产蚕茧７万担，２０００年晚秋蚕期传染性蚕病普遍发生，损失惨重，个别农户甚至颗粒无收，全乡平均张产不足３０公斤，比上年同期下降近５公斤。不仅造成大部分农户减产欠收，而且影响到蚕桑生产的巩固与发展，也给社会治安带来了不安定因素。１ 发病情况 特庸镇２０００年饲养晚秋蚕２０７３７张，９月９日出库，９月１８日发种至各育蚕室，９月１９日收蚁，二二眠前后开…     

推广桑蚕新品种“桂蚕一号”应注意的问题

对广西蚕业指导所在全区推广桑蚕新品种“桂蚕一号”进行跟踪调查，根据所调查市县的蚕农普遍反映该品种蚕好养，1－4龄蚕眠起齐一，产量高，茧大均匀，茧厚，茧色白，产量高达42－50公斤／张左右；比同期的“两广二号”增产7公斤／张左右，5龄经过长0．5－1天，蚕农普遍喜欢饲养。但部分新蚕区因品种性状不了解，饲养技术不到位，蚕农粗放饲养，蚕座过密，食桑不足，滥用蜕皮激素等，导致蚕发育不齐，大，小蚕，茧不匀，薄皮茧等，不能发挥“桂蚕一号”的优良性状。     

防止五眠蚕发生的技术措施

防止五眠蚕发生的技术措施龙游蚕种场刘乌南，姜以信，丰华丽，顾亚明，杨清源一、五眼蚕的发生现状龙游蚕种场在中秋养蚕制种中，常有五眠蚕发生。８０年代前期，本场在中秋期生产中，饲养浙农１号、苏１２两个原种，其中，以日系品种的苏１２，五眠蚕最容易发生，苏１２...     

雄蚕杂交种的饲养标准技术研究 1.不同温度与叶质对雄蚕稚蚕生理的影响

雄蚕杂交新品种夏华×平 8在春期用不同温度和叶质条件饲养,对其发育情况、龄期经过、稚蚕绝食生命时数和饥饿就眠率、眠蚕体重以及蚕茧产质量进行了调查.结果 1龄期收蚁 24小时用较高温度饲养,其绝食生命时数最长,2、 3龄均以中温饲养表现最好 ; 从饥饿就眠率看,1～ 3龄的总体表现以适熟叶最好 ; 从蚕茧产、质量看,以偏高温度饲养及适熟桑叶为好.     

家蚕四龄眠期不同体重与蚕茧产量关系的调查

在春、秋蚕期分别对现行蚕品种4龄眠蚕不同体重与蚕茧产量的关系进行了初步调查与分析。试验表明:在环境气候、饲育管理均较为一致的情况下,4龄眠蚕体重重,可增加蚕茧产量10%以上。强化4龄蚕的综合管理,是提高张种产茧量和蚕农经济效益的重要措施之一。     

中国饲料工业协会第五届理事会顾问、会长、常务副会长、副会长、秘书长、副秘书长、常务理事、理事名单

顾问刘中一张德邻宋瑞祥聂振邦张子仪戎易王维四会长白美清国务院原副秘书长、第四届理事会会长常务副会长(8人,以姓氏笔划为序)刘永好新希望集团董事长、第四届理事会副会长刘汉元通威股份有限公司董事长、第四届理事会副会长陈丹广东恒兴集团股份有限公司董事长、第四届理事会副会长张延喜农业部原副部长、第四届理事会副会长吴明夏湖南正虹科技发展股份有限公司董事长、第四届理事会副会长陶一山唐人神集团股份有限公司董事长、第四届理事会副会长温鹏程广东温氏食品集团有限公司董事长、第四届理事会副会长谭竹洲原化学工业部副部长、第…     

Evidence for the non-involvement of the uterus in the lifespan of the corpus luteum in the cyclic dog

Progesterone levels in peripheral blood of dogs were analysed during the cycle in which hysterectomy (n = 5) or sham surgery (n = 3) was performed as well as during the cycle of dogs (n = 5) hysterectomized at least one year prior to this study; the data were compared with the findings in control dogs (n = 3). The averages of the duration of the luteal period observed in the three experimental groups were not significantly different from those of control dogs. Immediately after surgery, the progesterone level decreased from 25 to 50% of the presurgical level, but returned to presurgical level in about four days. Prolactin levels were elevated for about 30 h after surgery. Nevertheless, the averages of the mean prolactin levels for each animal during the luteal period of the experimental groups were not significantly different from those of control dogs. It is concluded that in the dog, the uterus is not involved in the lifespan of the cyclic corpus luteum.     

The influence of the width of the saddle tree on the forces and the pressure distribution under the saddle

As there is no statistical evidence that saddle fit influences the load exerted on a horse's back, this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as "too-narrow" if they were one size (2 cm) narrower than the LOF saddle, and "too-wide" if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as "very-wide". In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm(2)+/-0.10; trot 1.08 N/cm(2)+/-0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm(2)+/-0.09; trot 0.86 N/cm(2)+/-0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm(2)+/-0.06; trot 1.52 N/cm(2)+/-0.19) and very-wide saddles (walk 0.77 N/cm(2)+/-0.06; trot 1.57 N/cm(2)+/-0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm(2)+/-0.10/ 0.63 N/cm(2)+/-0.11; trot 1.33 N/cm(2)+/-0.22/1.27 N/cm(2)+/-0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks.     

浅谈对症用药

对症用药就是通过对患病信鸽的症状进行诊断,进而确定病属,选择药物及如何用药的方法。     

军犬鉴别中的嗅源培养和易出现的问题及对策

嗅源是军犬嗅觉作业训练的依据.军犬鉴别中嗅源能力的培养在整个鉴别训练中占有重要地位,关系到鉴别训练的成败和鉴别能力的提高.所以,军犬在嗅认嗅源时必须按照训犬员的指令充分、细致地感受嗅源气味,并且对嗅源气味产生兴奋反应.如何培养军犬充分嗅认嗅源以及及时解决嗅认过程中出现的问题,成为我们进行鉴别训练的关键.……