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1.
Inhalt: An 81 Versuchs- und 92 Kontrolltieren der Rasse “Potnische Schwarzbunte” aus 3 Problembetrieben wurde ein Versuch zur Sterilitätsprophylaxe rnit der PRID-Spirale durchgeführt. Anhand klinischer Befunde und Milchprogesteronwerten wurde die Untergruppe aus Kühen mit Ovardystrophie (18 Versuchs- und 22 Kontrolltiere) gebildet und extra ausgewertet. Der Behandlungsbeginn lag zwischen 60 und 80 Tage post partum. Die Versuchstiere wurden mit der PRID-Spirale 12 Tage lang behandelt, die Kontrolltiere erhielten Injcktionen rnit Kochsalzlösung und solche rnit Ovardystrophie wurden zusätzlich mit einer Eierstocksmassage behandelt. Die Versuchstiere wurden 56 und 72 Stunden nach Entfernung der Spirale blind besamt. Die Brunstin-duktionsrate betrug insgesamt 90,1%, bei denen rnit Ovardystrophie 77,7%. Die An-wendung der PRID-Spirale führte zur Verbesserung der Fertilitätslage. Die Gesamt-trächtigkeitsrate lag mit 87,6% bei den Versuchskühenüber derjenigen der Kontrollkü-he mit 79,3%. Die Behandlung der Tiere rnit Ovardystrophie erbrachte eine Gesamt-trächtigkeitsrate von 88,8% bei den Versuchs- und 72,7% bei den Kontrolltieren. Die Zwischentragezeit betrug bei den Versuchstieren 101,2 Tage und bei den Kontrolltieren 113,3 Tage (p ≤ 0,05). Bei den azyklischen Tieren lag die Zwischentragezeit bei 104,6 Tage bzw. 134,7 Tage (p ≤ 0,05). In einem anderen Versuch wurde 20 Hybriden zwischen Wisent und Hausrind rwecks Zyklussynchronisation die PRID-Spirale verabreicht. Die Brunstinduktionsrate betrug 66,6%, das Erstbesamungsergebnis nach Doppelbesamung 30%, die Gesamtträchtig-keitsrate nach dem Decken der umrindernden Kreuzungstiere rnit einem Bullen 90%. Die Deckperiode konnte verkürzt werden. Contents: Investigations on the synchronization of estrus cycle in cattle from farms with fertility problems and in cross-breeds between bison and cattle with a PRID-de-vice In 81 experimental and 92 control animals of the “Polish Black and White” breed derived from 3 farms with fertility problems an investigation was carried out for sterility prophylaxis using the PRID-device. Based on clinical findings and milk progesterone values cattle with ovarian dystrophy (18 experimental and 22 control animals) from a special group were used. The begin of treatment was between 60 and 80 days post partum. All experimental animals had received a PRID-device for a duration of 12 days. Control animals were injected with physiological saline solution and animals with ovarian dystrophy were treated additionally with ovarian massage. Experimental animals were inseminated 56 and 72 hrs after removal of the device. All animals taken, estrus was induced in 90.1% of the animals, while only 77.7% of animals with ovarian dystrophy came to estrus. Application of the PRID-device led to an improvement of fertility. Pregnancy rates in experimental animals were 87.6%, while only 79.3% of the control animals were pregnant. Treatment of animals with ovarian dystrophy resulted in 88.8% pregnancies for treated and 72.7% for control animals. Experimental animals were non-pregnant for a duration of 101.2 days, while control animals remained non-pregnant for 113.3 days (p < 0.05). Acyclic cattle had a non-pregnant period of 104.6 days and 134.7 days (p < 0.05) respectively. In a second experiment 20 cross-breeds between bison and domestic cattle were treated with a PRID-device for synchronization of the estrus cycle. The rate of estrus induction was 66.6%, the fertility after double insemination 30%, the total pregnancy rate improved after mating with a bull of animals that had not conceived to 90%.  相似文献   
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针对人工监测奶牛发情费时、费力,仅依靠活动量和非接触式视频监测无法实现奶牛安静发情预警的问题,根据奶牛发情时阴道粘液生理特征变化,提出基于奶牛阴道电阻变化的奶牛发情监测方案。设计了由黄铜电阻探头、8爪防滑装置构成的奶牛阴道植入式电阻传感器,对阴道电阻值进行采集。借助2.4GHz的ZigBee网络开发了无线传输系统,将阴道电阻无线传送给协调器节点,协调器经由RS485总线传输到监控中心。开发了奶牛阴道电阻上位机实时监测系统,实现了奶牛阴道电阻的精确采集和远程实时监测。分别对植入式电阻传感器和监测系统进行了准确性、稳定性、可靠性及能量可用性试验,结果表明,植入式电阻传感器电阻测量探头体积小、安装方便,可测定1~1000Ω范围的电阻,测量精度在±2%以内,24h内电阻最大波动为2Ω;在450m2奶牛养殖区范围内,ZigBee网络数据发送成功率不低于98.5%;植入式电阻传感器终端节点在7.4V/6500mA·h锂电池能量供应下可连续工作38d。监测系统运行稳定,能够精确、可靠、实时地监测奶牛阴道电阻的变化,为奶牛发情程度和排卵时间的准确预测提供了一种新的监测方法。  相似文献   
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Conjunctival swabs collected in 1991-92 from 333 pedigree and non-pedigree cats were tested for the presence of Chlamydia spp. antigen using an ELISA antigen kit. Forty (18.4%) of the 217 samples from cats with conjunctivitis were positive. Seven (6%) of 116 samples from cats which were in contact with cats with conjunctivitis but which showed no clinical signs at the time of sample collection were positive. Positive-testing cats were frequently from multi-cat households. Chlamydia spp. is present and associated with conjunctivitis in cats in New Zealand. Infection may occur concurrently with viral diseases. Feline calicivirus was recovered from 27 (21 with conjunctivitis) of 37 cats tested in five catteries. Four cats (with conjunctivitis) were FIV-positive.  相似文献   
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Many fillies and mares are accused of behaving badly by their owners or trainers, and their reproductive hormones and ovaries are commonly blamed for this. Overt oestrus behaviour, however natural, is undesirable when a horse is being ridden, trained and competed. More subtle behaviours may be attributed to the reproductive cycle and presented as the cause of poor performance in the elite competition mare. Sometimes behaviours are complex, perhaps at odds with what one expects for normal reproductive behaviour and in many cases may not be associated with the reproductive cycle at all, rather associated with pain of musculoskeletal or soft tissue origin. The situation represents a diagnostic dilemma to positively associate undesirable behaviours with the ovarian hormones or ovarian pain, before an attempt can be made to modify the behaviour through the suppression of oestrus. This article will review the reasons for presentation, the behavioural patterns of the reproductive cycle and the diagnosis of reproductive behavioural problems. The range of techniques for oestrus suppression will be reviewed along with their clinical application and any known current regulatory issues associated with their use.  相似文献   
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系统研究了小尾寒羊、同羊、滩羊血液褪黑激素在春分、夏至、秋分时的昼夜变化规律,发现绵羊血液中褪黑激素存在着明显的季节性变化,在春分和秋分时平均含量相对较低,在夏至时明显升高。在夏至和秋分时,小尾寒羊和同羊血液中褪黑激素比滩羊低,在春分时,小尾寒羊褪黑激素比同羊和滩羊高。  相似文献   
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The object of this investigation was to determine the relationships between clinical findings and hormonal patterns in primiparous sows with different lactation length and litter size during lactation, weaning and to the first oestrus. Seven pairs of primiparous full sib sows were used to determine the effect of lactation length with normal litter size. One sow of each pair was assigned to nurse the piglets for 3 weeks (group A) while the other nusred for 5 weeks (group B). Another 8 primiparous sows (group C) were assigned to nurse 2–4 piglets during a 5-week lactation period. Oestrus detection was performed twice daily and laparoscopic examination every 2 weeks. If the sows did not come in oestrus within 3 weeks after weaning they were slaughtered. Peripheral plasma levels of progesterone, oestradiol-17β and LH were estimated by radioimmunoassays throughout the experimental period.  相似文献   
8.
[目的]探讨提高奶牛冷冻胚胎移植妊娠率方法。[方法]对比1次、2次同步发情奶牛冷冻胚胎移植受体母牛的试验妊娠率。[结果]1次、2次同步发情胚胎移植妊娠率分别为44.45%和70.73%。[结论]同步发情对胚胎移植妊娠率有很大影响,2次同步发情可显著提高奶牛冷冻胚胎移植妊娠率。  相似文献   
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The present study aimed to evaluate the effect of a single intramuscular injection of melatonin on response of oestrus, rate of conception, ovarian and uterine blood supply during the non-breeding season. Melatonin powder was dissolved in dimethyl sulfoxide (DMSO) and olive oil and injected in two dose of 25 mg (MEL-1; n = 10) and 50 mg (MEL-2; n = 10) in May. Ten ewes were served as the control (CON). Results showed that oestrous response was higher in the MEL-2 group than in other groups (p < .01). The time to onset of oestrus in both the MEL-1 and MEL-2 groups was significantly shorter, compared with the CON group (p < .01). Pregnancy rates reached 80% and 90% at 45 days of gestation. Doppler indices of the right and left ovarian artery were lower in the melatonin groups than in normal groups (p < .01). Both Doppler indices in uterine arteries were not different among two treatment groups (p > .05), but there was a significant difference when compared with the CON group (p < .01), no difference found between two treatment group in the Doppler velocities of middle uterine arteries (p > .05). In conclusion, the definite changes in the studied parameters showed two novel findings; (a) the increase in melatonin dose results in increasing the blood flow expressed by increased Doppler velocities in fatty tailed ewes, (b) as well as, melatonin can initiate the breeding season regardless of the season earlier by 1–2 months in ewes.  相似文献   
10.
泌乳奶山羊非繁殖季节诱发发情研究   总被引:2,自引:0,他引:2  
奶山羊具有明显的季节性发情的特点,在非繁殖季节里,泌乳母羊体内的催乳素水平要高于繁殖季节,从而抑制了卵巢的生理机能。本研究采用具有抑制催乳素分泌作用的溴隐亭(CB-154,Parlodel)药物来降低母羊体内的催乳素水平,配合使用促性腺激素,提高泌乳母羊的诱发发情率,使配种后不返情率达到80%(28/35)。  相似文献   
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