配种后母牛返情的原因分析及对策

配种受孕率是衡量奶牛场生产成绩的一个重要指标,而配种后母牛的返情会造成产犊间隔的延长、精液成本和饲料成本的增加,严重影响牛场的生产成绩和经济效益。所以减少配种后母牛返情的发生就显     

母猪配种后返情原因浅析

母猪繁育率的高低是影响猪场经济效益的重要因素之一,母猪配种后返情直接影响母猪繁育率.从受精失败及胚胎着床失败导致的返情两个方面介绍了母猪配种后返情的原因,以更好地解决母猪配种后返情的难题.     

生产母猪返情的主要原因与对策措施

生产母猪的返情现象在国内外各大猪场普遍存在,然而不同的管理方式,母猪的返情率有高有低。一般猪场的配种分娩率为80％-90％,配种后未分娩的10％～20％母猪,大部分是因为配种后出现返情现象。返情率的增加,会导致配种分娩率降低,从而降低母猪的繁殖率,影响养猪场的经济效益。据生产实践,母猪返情不外乎三方面因素：公猪,母猪,管理。     

配种母猪返情的原因及处理措施

繁殖母猪发情期进行配种后没有怀孕的现象称为返情.一般多发生在母猪配种后的18~24d.配种后的繁殖母猪返情率的增加,会导致配种分娩率降低,从而影响养殖户的经济效益.     

母猪配种后返情的原因及有效防控

猪的发情周期为18~24天。繁殖母猪于发情期配种后未怀孕的情况被称作返情。返情率高会降低配种分娩率,减少养殖户的经济收益。导致母猪返情的原因较多,以下对其中的几点主要原因进行总结,并给出相应的防控措施。     

用频率分布法分析母猪返情的主因素,提高规模猪场的配种分娩率

尽管国内的规模猪场长期以来不断采取各种措施,力图提高母猪的繁殖率,但是场根据母猪的个体记录,统计出的真实的母猪配种分娩率仍然很低。美国谷物协会猪场场间比较系统中,2004年全国约50家大型养猪企业的约10万头母猪53周的平均配种分娩率仅约77%。这样的成绩不仅与同样使用人     

配种母猪返情的原因与减少返情率的措施

配种分娩率是衡量猪场生产成绩的重要指标,而配种后母猪的返情会降低配种分娩率,影响猪场生产成绩和经济效益。所以,提高母猪配种分娩率的重要途径是减少配种后母猪返情的发生。     

降低母猪返情率的技术措施

配种分娩率是衡量猪场生产成绩的重要指标,而配种后母猪的返情会降低配种分娩率,影响猪场的生产效益。所以,提高母猪的配种分娩率的重要途径就是要减少配种后母猪返情情况的发生。本文就畜牧生产中母猪配种返情的原因及应对措施总结如下。     

福建省龙海市某猪场母猪返情情况调查分析及应对措施

对福建省龙海市某猪场2010—2012年的母猪配种和返情情况进行统计,通过数据分析得出,每年6—8月的返情率比较高,夏季返情率均在15%以上;配种45~105 d内出现返情的概率最大,约占34.3%,且配种45~105 d内大部分返情母猪都是由于发生了流产所致。这主要是由于夏季气温较高,对配种成功率干扰很大,加之该场不注重应激对怀孕母猪的影响。因此,建议该场应降低配种后母猪的应激,改善配种后母猪的饲养管理,改善种公猪饲养环境,提高配种人员和采精人员的技术水平,以减少母猪返情的发生。     

母猪乏情和返情的主要原因和对策

当前，在猪的繁殖方面，令养猪者十分头疼的问题是母猪的乏情和返情。所谓乏情就是不发情，后备母猪到了该发情的年龄和体重不发情，或者母猪断奶后发情推迟或不发情。返情就是配过的母猪，在一个情期（3周左右）后再发情，有的甚至屡配不孕。乏情和返情是造成猪群受胎率低、分娩率低和母猪年产胎次少的主要因素之所在。     

引起猪繁殖障碍的因素及对策

近几年,猪繁殖障碍症成为我国一些规模化猪场或中小型养猪场的常见病和多发病,给养猪场带来一定的经济损失.猪繁殖障碍在临床上常表现为:空怀母猪不发情或母猪断奶-再发情间隔延长(间情期延长),母猪配种后不受胎,屡配不孕,妊娠母猪返情或发生流产、早产、产死胎、木乃伊胎或产出无活力的弱仔、少仔和畸形胎(即猪SMEDI综合征:流产、死胎、木乃伊);公猪性欲低下甚至无性欲、阳萎,无精、弱精、死精或畸形精子比例增高.     

DNA hybridization procedure to detect pseudorabies virus DNA in swine tissue

A DNA hybridization technique was developed to detect the presence of pseudorabies virus (PRV) DNA. P Nick translated probes of high specific activity were prepared from transformed Escherichia coli plasmids into which Bacillus amyloliquefaciens H (Bam H1) restriction fragments of PRV DNA had been inserted. Swine cellular DNA and tissue culture PRV DNA were digested with Bam H1, separated by agarosegel electrophoresis, transferred onto nitrocellulose paper, hybridized to the radioactive probes, and washed under high stringency conditions; autoradiographs were then prepared. Under the optimal hybridization conditions described, the detection limit of these probes was 10(-11)g of PRV DNA. In reconstruction experiments, 3 of the selected probes cross hybridized with digested swine cellular DNA, and 4 probes did not. The addition of polyuridylic acid and polyguanylic acid to the hybridization reactions did not alter the amount of hybridization. The results indicated that this procedure may be useful for studying the latency of pseudorabies viral infection.     

广东畜产品安全面临的问题与对策

畜禽产品质量安全问题,是当前发展现代畜牧业的主要"瓶颈"之一.在保证数量有效增长的同时,提高畜产品质量安全,是全面建设现代畜牧业的必然要求.广东畜牧业在国内具有自身的特色,凭借面临港澳的地理优势,容易形成出口型畜牧业,对畜产品安全的要求更为严格.     

Time to onset of oestrus after the injection of heifers with cloprostenol

When two injections of 500 microgram cloprostenol are given 11 days apart to unselected cycling heifers the onset of oestrus behaviour is significantly earlier, and more compact, after the second injection than after the first. The time from treatment to the onset of oestrus following this second injection was not significantly different from that obtaining in animals given a single injection on day 8 of the oestrous cycle. It is suggested that the more precise onset of oestrus after the second of two cloprostenol injections is due to the majority of animals being at a comparable stage of the oestrous cycle when the treatment is given. The earlier oestrus after two cloprostenol injections may be due to the greater number of heifers at days 7, 8 and 9 of the oestrous cycle at the time the second injection is given.     

马岗鹅繁殖性能低下的原因分析及解决办法

本文从繁殖机制、光照、营养条件、饲养管理、环境因素、育种、人工授精和人工孵化共八方面分析了马岗鹅繁殖性能低下的主要原因,提出相应的解决办法。     

In situ hybridization for the detection and localization of swine Chlamydia trachomatis

Gnotobiotic piglets were inoculated intralaryngeally with swine Chlamydia trachomatis strain R33 or orally with swine C. trachmatis strain R27. Archived formalin-fixed, paraffin-embedded tissues from piglets euthanatized 4-7 days postinoculation were examined by in situ hybridization for C. trachomatis nucleic acid using a nonradioactive digoxigenin-labeled DNA probes that targeted specific ribosomal RNA or omp1 mRNA molecules of the swine C. trachomatis strains. Positive hybridization signals were detected in bronchial epithelial cells, bronchiolar epithelial cells, pneumocytes, alveolar and interstitial macrophages, and jejunal and ileal enterocytes. Chlamydia-infected cells had a strong signal that was confined to the intracytoplasmic inclusions. Positive hybridization signals were not detected in tissue sections from an uninfected control piglet or in C. psittaci-infected sheep placenta. The morphology of host cells was preserved despite the relatively high temperature required in parts of the incubation procedure. The data indicate that in situ hybridization can be used to detect swine C. trachomatis in formalin-fixed, paraffin-embedded tissue specimens.     

加入WTO对山东省饲料工业的影响及对策

三、应采取的对策 1.继续推进企业改革,加快饲料工业的结构调整 饲料工业的结构调整要以市场为导向,以企业为主体,以技术进步为支撑,突出重点、有进有退,在转型升级换代上下功夫。一是“抓大促小”,通过兼并、联合、租赁、承包、拍卖、股份、重组等     

加入WTO对山东省饲料工业的影响及对策

一、全省饲料工业发展现状 山东省饲料工业从上个世纪80年代初开始起步,经过20年的发展,在数量、质量、结构、效益等方面,均取得了令人瞩目的成就。初步建立了饲料加工、饲料原料、饲料添加剂、饲料机械以及教育、科研、监测和行业管理等体系,涌现出一批大型骨干企业和企业集团,形成了多种所有制形式并存、多种经济成分共同发展的良好格局,成为我省国民经济中的重要产业,在我省39大     

Fertility in buffaloes after oestrus synchronisation with cloprostenol and fixed time insemination.

Fifty-seven cycling buffalo cows of the river type were treated with two doses of 0.5 mg cloprostenol intramuscularly given 11 days apart. Each animal was inseminated twice at 72 and 96 hours after the second injection of cloprostenol. The first service conception rate diagnosed by rectal palpation at 90 days was 38.6 per cent. At the time of insemination the cervix was easily penetrable on both days in only 39 (68.4 per cent) of the animals. They were inseminated at or beyond the internal cervical os, while the others were inseminated in the cervical canal. There was a marked difference in conception rate between those receiving deep inseminations (48.7 per cent) and the others (16.7 per cent). In relation to the interval from calving to insemination the conception rates for those which had calved 60 to 90, 90 to 120 and 120 to 150 days earlier were 16.6, 36.4 and 55.5 per cent respectively. The use of cloprostenol treatment and fixed-time insemination is a useful method of overcoming the problem of oestrus detection in buffaloes. Acceptable levels of fertility can be obtained in those animals which have a sufficiently relaxed cervix to permit semen deposition at the internal os, provided the interval from calving to insemination is more than 90 days.     

加入WTO对我国肉牛业发展的影响及应对措施

2.2加入WTO对我国牛肉贸易的影响 加入WTO将对我国牛肉的进出口贸易产生一定的影响,但在近期内不会对我国的肉牛业带来冲击。 就进口方面来说,尽管我国在入世后对牛肉征收的进口关税降幅比较大,但其受到的冲击不会太大,一个重要原因就是目前能向我国出口的牛肉主要是高档的牛排肉。这样的牛肉在它的产地价格就不菲,进入我国市场后主要在高档宾馆