Hormonal treatments for fertility disorders in cattle

In dairy cows, hormonal treatments are commonly implemented for acyclicity, silent heat and endometritis. Before treatment, causes of infertility need to be detected and severe failures in housing, feeding or other diseases must be eliminated. Without sustainable improvement of herd management, the use of intensive hormonal treatments will not improve reproductive performance. The most common cause of anoestrous is silent heat. In cows with a palpable corpus luteum, injection of prostaglandin F2α (PGF) reliably induces oestrous. A satisfactory treatment for acyclicity (ovarian dystrophy, ovarian cysts) does not exist. Combinations of different hormones have greater treatment success than a single use of gonadotrophin releasing hormone (GnRH) or human chorionic gonadotrophin (hCG). Strategic use of PGF during the early postpartum period cannot be recommended because positive effects on uterus involution and resumption of the oestrous cycle after calving have not been verified. In contrast, application of GnRH combined with PGF in the puerperal phase appeared to have positive effects on fertility of cows with endometritis. The same applies to PGF for cows with chronic endometritis. Cases of endometritis with fetid odour of vaginal mucus or isolation of Trueperella pyogenes should be treated with antibiotics. Treatment before the 27th day post partum is not advisable. In conclusion, hormonal treatments can be used to treat fertility disorders. Nevertheless, in order to enhance the reproductive performance at the herd level, a sustainable improvement of the general conditions (housing, feeding, animal health, management) is a prerequisite.     

电针辅助治疗奶牛常见不孕症试验

对农七师123团奶牛场16头诊断为不孕症的奶牛用常规方法进行了治疗，其中11头奶牛患子宫内膜炎，另外5头患卵巢静止。对石河子大学动物科技学院试验站4头诊断为不孕症的奶牛在采用常规子宫注射中药同时进行了电针辅助治疗，其中2头奶牛为子宫内膜炎，另外2头为卵巢静止。对这两组奶牛进行了治疗效果的对比。结果表明，采用电针辅助治疗的4头患不孕症的奶牛全部有效，受胎率是75％。而只采用常规治疗方法组的总有效率为75％，受胎率是62．5％。两者比较差异不显著（P〉0．05），但是前者的疗程较短。     

Research Progress on Diagnosis Methods of Subclinical Endometritis in Dairy Cows

In the absence of clinical symptoms,dairy cows with subclinical endometritis are defined as sustainably extensive infiltration with the polymorphonuclear cells (PMN) in endometrial samples,and it often lead to dairy cow with repeated infertility.In China,the infertility proportion of dairy cows is 50.62% caused by endometritis,in which 90% is caused by subclinical endometritis.It is difficult to be observed during the early stage of subclinical endometritis,and the best treatment time is delayed in the most cases causing huge economic losses.So it has become a research hotspot to make correctly and timely diagnosis of this disease.At present,the main diagnosis methods of dairy cows subclinical endometritis are vagina endoscope method,cell brush,biopsy technology,ultrasonic diagnosis technology,leukocyte esterase method and so on.However there is no uniform criterion.Different diagnosis methods of subclinical endometritis were summarized,analyzed and discussed in this paper to provide the references for the subclinical endometritis diagnosis more accurately and earlier,and reduce the losses of dairy farms.     

奶牛隐性子宫内膜炎诊断技术研究进展

奶牛隐性子宫内膜炎在以子宫内膜被嗜中性粒细胞(PMN)持续性的广泛浸润为主要特征,没有直观的临床症状,经常导致奶牛屡配不孕。在中国,由子宫内膜炎引起的奶牛不孕的比例达50.62%,且由隐性子宫内膜炎引起的奶牛不孕占其中的90%。由于隐性子宫内膜炎在发病初期不易被观察到,容易错过最佳治疗时间,造成巨大的经济损失,故如何对其做出正确、及时的诊断成了近年来的研究热点。目前,国内外奶牛隐性子宫内膜炎的诊断方法主要有阴道内窥镜法、细胞刷法、活体组织诊断法、超声诊断法及白血球酯酶法等,但目前这些诊断方法没有统一的判断标准。本文对几种不同的奶牛隐性子宫内膜炎的诊断方法进行了综述,为更早、更准确地诊断隐性子宫内膜炎提供依据。     

奶牛子宫内膜炎诊疗学研究进展

子宫内膜炎是奶牛产后普遍发生的一种生殖疾病,可导致奶牛产犊间期延长、产奶量降低、淘汰率增加、治疗期间奶源废弃、管理及治疗成本增加,也是导致奶牛不孕症的重要原因之一。目前国内外防治奶牛子宫内膜炎的诊断技术和治疗方法众多,主要有阴道镜检查、Metricheck装置评估、子宫细胞学检查、抗生素疗法、中药疗法、中西医结合疗法、激素疗法、臭氧新型疗法等诊疗技术。阴道镜检查是一种可视化检查方法,利用内窥镜直观评估奶牛阴道内分泌物性状确定子宫内膜炎严重程度;Metricheck装置是根据阴道内分泌物含量和性状,设置不同评分值评估产后奶牛子宫内膜炎和繁殖性能;子宫细胞学检查通过子宫细胞刷、灌洗或活检技术确定子宫内膜细胞和中性粒细胞（PMN）的比例,设定奶牛产后不同时期PMN最佳阈值诊断子宫内膜炎;抗生素疗法通过宫内灌注、皮下注射、静脉注射抗生素等途径治疗奶牛子宫内膜炎,治疗成本低,见效快,是目前治疗奶牛临床子宫内膜炎最常用的疗法;中药疗法筛选不同组分的中药复方制剂,通过调节奶牛机体免疫系统,改善子宫内血液循环,抑制致病菌繁殖,促进子宫恢复正常生理机能;中西医结合疗法兼具中药辩证治疗的优点和西药见效快的特点,临床治疗奶牛子宫内膜炎具有广泛应用价值;激素疗法中前列腺素通过诱导黄体溶解,消除黄体酮产生和免疫抑制,刺激子宫复旧,降低产后奶牛长期子宫感染和炎症的风险;臭氧新型疗法是将臭氧制作成泡沫制剂、油制剂等产品通过宫内灌注杀灭病原菌。这些诊疗技术在治疗奶牛子宫内膜炎的过程中均取得了不同程度的效果,对评估产后奶牛繁殖性能和生产性能具有良好的指导作用。文章通过介绍这些诊疗技术在奶牛子宫内膜炎中应用的研究进展,以期为该病的防治提供参考。     

Pathological changes in the reproductive organs of cows and heifers culled because of infertility

The reproductive organs of 20 Estonian Holstein Breed (EHF) cows and three heifers, culled because of infertility, were studied by palpation per rectum and ultrasonography. In addition, pathoanatomical and pathohistological studies were carried out after slaughtering. The pathohistological study revealed that small cysts often (12 animals) existed in culled cows, whose diameter was less than 2.5 cm. These cysts were frequently accompanied by changes in secondary and Graafi follicles, rete ovarii, ovarian stroma, and the endometrium. Three cows had follicular cysts in the ovaries, which were 25-35 mm in diameter. Two cows revealed luteal cysts in the ovaries; one of them had vaginal prolapse. Four animals (one heifer and three cows) manifested tumours or tumour-like malformations: ovarian endosalpingiosis, germ and stromal cell tumour, oviductal myolipoma, and haemangiosarcoma in the uterine blood vessels. One heifer had been culled because of two abscesses in the vaginal wall close to the cervix and another had chronic endometritis. The research findings indicate that the most common cause of infertility in the culled cows was cystic degeneration in ovaries (85%), accompanied by pathological changes elsewhere in the reproductive organs. We claim that these changes are responsible for the low pregnancy rate after the treatment of ovarian cysts. The second most common reason was genital tumours (15%). In heifers, infertility is rare and its causes are heterogeneous.     

Reasons for culling in French Holstein cows

The study describes the profiles of culled cows in order to assess the possible contribution to economic losses due to health disorders. Data regarding dates of birth, final calving and culling, parity at culling, milk yield at the two first test-days of the final lactation and reason(s) for culling were collected in a 5-year survey, carried out from 1989 to 1994 in 84 commercial Holstein farms in western France. Polytomous logistic regression was used to assess the relationship between parity, calving-to-culling interval, milk yield and eight groups of primary culling reasons (i.e. udder disorders; infertility or reproductive disorders; lameness or foot/leg defects; emergency culling reasons; other health disorders; low milk yield; sales for dairy purpose; and other voluntary culling reasons). Out of a total of 5133 culled cows, the proportions of culls, for each of these groups of reasons, were 12.4, 28.4, 2.7, 3.9, 4.6, 16.7, 5.9, and 25.4%, respectively. Cows culled for udder disorders left the herd earlier in lactation and were more frequently at parities 4–6 than cows culled for voluntary reasons. In contrast, cows culled for infertility were younger and culled later within lactation. They were also higher yielding cows than those culled for other reasons. Cows culled for lameness were similar to those of the voluntarily culling group. Cows culled for emergency reasons were more frequently younger cows in early lactation. Cows culled for other health disorders left the herd early in lactation, but at a higher parity than the voluntarily culled cows. These results suggest that most of the culls related to health could be contributing to economic loss. However, special priority should be given to reduce culling for reproductive problems, which is the most costly exit reason.     

Forms of Reproductive Disorders in Cattle and Buffaloes in Middle Egypt

The objective of this study was to investigate the common forms of reproductive disorders and trends of fertility in cattle and buffaloes in Middle Egypt, and investigate nutritional deficiencies or imbalances as a cause of infertility. During the period from 2003 to 2006 a total of 4276 animals (2755 cattle and 1521 buffaloes) were examined, during winter and summer at three districts of Middle Egypt. Based on the owner complains, animals were categorized as anestrum, repeat breeder and those for pregnancy diagnosis. Feedstuffs of these districts were assessed for nutrient and mineral contents. Animals were examined by rectal palpation and by transrectal ultrasonography. The results showed that, ovarian inactivity was the most common cause of anestrum, whereas endometritis was the main frequent finding of repeat breeding. District, season and year affected the incidences of infertility. The pregnancy rate remained constant (cattle) or increased (buffaloes) from 2003 to 2006. The incidence of ovarian inactivity in both species decreased over the same period. In winter, the commonly used feedstuffs would be adequate to supply the animals with needs, but in summer, rations seem to be deficient in many essential nutrients. In conclusion, ovarian inactivity is the main cause of infertility in cattle and buffaloes in Middle Egypt. There is a link between poor nutrition in summer and the high incidence of ovarian inactivity. Fertility trends during the past few years are encouraging.     

屡配不孕奶牛血清维生素A、E及铜、锰、锌水平的检测分析

本试验采用原子吸收光谱法和荧光吸收光谱法对14头屡配不孕奶牛和10头正常奶牛血清铜、锰、锌及维生素A、维生素E水平进行检测分析,旨在了解重庆市某奶牛场奶牛屡配不孕与血清中部分微量元素及维生素水平的关系。结果显示,屡配不孕奶牛血清锌、维生素A和维生素E含量与正常奶牛相比差异显著(P0.05),血清铜、锰含量与正常奶牛无明显差异(P0.05)。从检测结果分析推测,血清锌、维生素A和维生素E水平过低可能是造成奶牛屡配不孕的原因之一。     

Rationale for treatment of endometritis in the dairy cow

Endometritis is an inflammation of the uterine lining that is commonly initiated at parturition. The degree of its effect on fertility varies with the severity of the inflammation, the time required for resolution of endometrial lesions, and the extent of permanent changes that impair endometrial gland functions and/or alter the uterine and/or oviductal environment. The primary nonspecific organisms associated with endometrial pathology are Corynebacterium pyogenes and the gram-negative anaerobes. The majority of postpartum dairy cows have some degree of endometritis but resolve it by 40 to 50 days post partum. Cows with certain periparturient disorders involving the reproductive tract and/or a defective host immune mechanism may acquire persistent infections that impair subsequent fertility. Not all infertile cows or all cows with positive uterine cultures have endometritis. Cows recovering from C. pyogenes endometritis may require 1 month after clearance of the organism for fertility to be restored. These cows, as well as many cows with slightly delayed uterine involution at 30 days post partum, do not benefit from antimicrobial therapy. The effect of endometritis varies between herds. It is associated with prolongation of calving intervals that can vary from less than 2 weeks to 2 months or more. The cost of days open beyond 80 to 110 days post partum is currently estimated to be $2.00 to $2.25 per day. Evaluation of the bovine genital tract is best conducted by a rectal examination combined with a vaginal speculum examination. Cows selected for therapy for endometritis should meet the strict requirements of a grossly enlarged uterus and a severely abnormal uterine discharge. Induction of estrus is the treatment of choice whenever possible. When antimicrobial therapy is indicated, tetracycline is recommended for intrauterine use during the early postpartum period when mixed bacterial populations are present. Commonly used doses are 2 to 3 gm. For systemic signs of illness, systemic administration of penicillin has been recommended. Twice daily doses of 5000 to 10,000 IU of penicillin per kg may be necessary to maintain therapeutic blood concentrations. Systemic administration of an antimicrobial is necessary to achieve therapeutic concentrations in the oviducts, cervix, and vagina. With chronic endometritis due to C. pyogenes, intrauterine administration of 1 to 1.5 X 10(6) IU of procaine penicillin G has been recommended. Multiple daily treatments are desirable. Milk from treated cows should be tested for penicillin before it is added to bulk tank milk. It still is not clear whether antimicrobial therapy is cost effective.(ABSTRACT TRUNCATED AT 400 WORDS)     

奶牛子宫内膜炎研究进展

子宫内膜炎是奶牛中一种常见的产科疾病,它可引起奶牛不孕,给奶牛养殖带来严重经济损失。引起奶牛子宫内膜炎的主要原因可概括为理化性和生物性二类,病原菌的侵入可通过上行性感染和下行性感染的途径造成子宫炎的发生,主要致病菌有葡萄球菌、大肠埃希菌、链球菌等。直肠检查和内窥镜检查仍是奶牛子宫内膜炎的常规的诊断方法,但仍有待于探索简便准确的新诊断方法。恢复子宫张力,促进子宫血液循环和炎性分泌物排出,抑制或消除子宫内感染病菌是子宫内膜炎的主要治疗原则,常用的治疗方法有冲洗子宫,全身疗法,抗生素和激素疗法以及中药治疗等。创建新的治疗和诊断方法,开发疗效好的药物将是提高奶牛子宫内膜炎诊疗水平的努力方向。     

淮北地区黄牛不孕症研究──Ⅰ·临床学调查

查明了淮北地区鲁西黄牛初情期等１０项生殖生理参数；证实不孕症发病率为２６．３％及其分类，；应用微生态方法定量检测不孕牛阴道菌群，查明优势菌为表皮葡萄球菌和链球菌     

奶牛产后子宫感染与子宫免疫

非特异性子宫感染会降低奶牛的生产性能和奶牛场的潜在效益。发生子宫感染时常并发感染化脓性放线杆菌或混合感染其他细菌。当从产后21 d的奶牛子宫液中分离到化脓性放线杆菌时,说明奶牛发生了严重的子宫内膜炎,并且将导致产后第一个发情期不孕。然而引起子宫感染的确切原因尚不清楚,但可以肯定与多种因素有关。发生难产、胎衣不下、怀有双胎或死胎以及患有各种代谢紊乱疾病的奶牛比其他奶牛更容易发生子宫感染。分娩前后异常的免疫功能更容易导致发生严重的子宫感染。子宫感染一般不会引起奶牛死亡,但是发生子宫感染的奶牛其生产性能会受到很大影响。另外,子宫发生感染还会降低产奶量,并且对子宫感染的一些治疗措施还会对牛奶产生污染。因为感染的非特异性,所以子宫感染很难预防;注意加强卫生设施以及围产期的卫生,特别是在助产过程中的卫生,才可能是最好的预防方法。异常免疫功能导致奶牛发生子宫感染的现象,说明通过对免疫功能的调节来预防和治疗围产期奶牛子宫感染是有潜力的。     

Subclinical endometritis in dairy cattle and its effect on fertility--a review of recent publications

Reduced reproductive performance in dairy cattle is often caused by uterine disorders. Beside acute metritis and chronic endometritis recent reports on a negative impact of subclinical endometritis on reproductive performance have been published. Diagnosis of subclinical endometritis can be performed by ultrasonography or cytological examination of the uterus. The cytological examination is based on uterine lavage or the cytobrush-method. Prevalence of subclinical endometritis in different studies ranges from 16 to 90 percent and depends on the diagnostic method and the time postpartum when the examination is performed. Affected cows showed significantly decreased conception rates, prolonged days to first service and days open as well as a reduced number of cows pregnant. Studies on the treatment of subclinical endometritis with prostaglandin F2alpha or analogues, intrauterine antibiotics or proteolytic enzymes showed heterogeneous results and do not allows valid recommendations for veterinary practice.     

奶牛子宫内膜炎病因学研究进展

奶牛子宫内膜炎是奶牛养殖业最常见的疾病之一,每年因该病给养殖业带来的损失不可估量。引起该病的主要病因除了有细菌、真菌、支原体等一系列病原微生物以外,激素紊乱、遗传、疾病等奶牛自身因素以及营养、环境和不科学的饲养管理因素同样也会导致本病发生。因其病因因素较多,加大了治疗难度。因此,论文以近年来国内外最新的研究资料为基础,从诱发该疾病的病原微生物、奶牛自身因素和不当的人为因素等方面对奶牛子宫内膜炎的病因进行系统的综述,以期为预防和治疗此类疾病提供参考。     

Prevalence of clinical endometritis and its impact on reproductive performance in grazing dairy cattle in Argentina

The objective of this study was to evaluate the prevalence of clinical endometritis and its impact on reproductive performance in grazing dairy cattle in Argentina to compare data with previous reports from herds kept in confinement housing systems. A total of 243 Holstein dairy cows from three commercial dairy farms in Buenos Aires Province (Argentina) were examined for the signs of clinical endometritis 18-38 days postpartum (dpp) by external inspection and manual vaginal examination. Vaginal discharge was scored into the categories VDS 0 (transparent, clear mucus), VDS 1 (mucupurulent discharge), VDS 2 (purulent discharge) and VDS 3 (purulent discharge with fetid odour). Cows diagnosed with VDS 1 to VDS 3 were regarded as affected with clinical endometritis and cows with VDS 0 as free of clinical endometritis. All cows were re-examined 14 days later following the same examination protocol. Prevalence of clinical endometritis 18-38 dpp was 35% and decreased to 18% at re-examination. Cows with no palpable ovarian structures or periparturient disorders were at higher risk for clinical endometritis. Hazard for pregnancy was significantly lower in cows with purulent or fetid odour discharge compared with reference cows with no discharge (HR=0.49; p=0.01), resulting in a lower proportion of cows pregnant by 360 dpp (66% vs 78%). Furthermore, the number of services per pregnancy was higher for cows with clinical endometritis than for cows without clinical endometritis (4.4 vs 3.1; p=0.04). Cows with clinical endometritis were 1.6 times as likely to be culled as cows with no signs of clinical endometritis. In conclusion, the prevalence and the impact of clinical endometritis in a pasture-based, extensive dairy production system in Argentina were similar to previously published data from dairy farms with confinement production systems.     

Use of culled cows as embryo donors

In a trial, 134 donors (cows and first-calvers) culled for slaughter owing to a low performance, udder disease, infertility and other reasons (termination of productive age, foot disease, etc.) were treated with 2000 to 4000 i. u. PMSG (Serum gonadotropin, Bioveta) to induce superovulation. The embryos were obtained post mortem on the sixth to ninth day after the first insemination. Among the donors culled for infertility the proportion of superovulated animals was 53.1% and among those culled for "the other" reasons this proportion was only 46.2%; out of the cows eliminated for a low performance and udder diseases 76.3% and 70.6% were superovulated. The highest stimulation was obtained in cows culled for "the other" reasons (14.58 CL) and for infertility (12.41 CL). The level of embryo gain was good in donors culled for a low performance (57.3% of CL number, 6.82 eggs), for "the other" reasons (59.3%, 8.64 eggs) and for udder diseases (62.6%, 6.83 eggs), it was the lowest in infertile donors (46%; 5.71 eggs-P-insignificant). These donors had the largest proportion of embryos suitable for transfer--66.9% out of the eggs obtained. A good proportion of suitable embryos was also found in donors culled for a low performance (61.7%) and for "the other" reasons (55.8%); the lowest proportion of suitable embryos was obtained in the donors with diseased udders (48.8%). Good proportions of superovulated donors (from 53.5% to 85.7%) and acceptable results of stimulation were kept for about a year after calving.(ABSTRACT TRUNCATED AT 250 WORDS)     

奶牛常见繁殖障碍疾病及防治措施

繁殖障碍是奶牛饲养过程中一类常见的疾病,可导致奶牛繁殖性能降低。子宫内膜炎、胎衣不下、卵巢囊肿等疾病是引发奶牛繁殖障碍的主要原因。此外,遗传、营养、环境等因素也可造成奶牛繁殖障碍,严重影响奶牛的正常生产,对我国奶牛养殖业造成巨大的经济损失。本文对引起奶牛繁殖障碍的疾病原因、临床症状、治疗方法和预防措施进行论述,提高奶牛场对该病的认识。     

Über die Bedeutung von Mycoplasmen als Sterilitätsursache beim Rind*

A review of the literature is presented on the strains of Mycoplasma isolated from the bovine genital tract and their relationship to infertility. Although Mycoplasmas have frequently been isolated from the genital organs of bulls, no typical clinical symptoms have been observed and no detrimental effects on spermatozoa have been shown. Mycoplasmas can be transmitted to cows by artificial insemination. In contrast to bulls, Mycoplasmas have been described as causing inflammatory changes such as cervicitir, endometritis and salpingitis in cows. Salpingitis, which may lead to obstruction of the oviduct, has the most serious consequences of later infertility. The author's own observations on the occurrence of Mycoplasmas in the herds in one area are briefly described. Prophylactic and therapeutic measures against genital Mycoplasma infections in cattle are also given.     

Acute-phase protein concentration and metabolic status affect the outcome of treatment in cows with clinical and subclinical endometritis

The aim of this study was to investigate the role of acute-phase protein concentration and metabolic status in the establishment and resistance of clinical endometritis (CE) and subclinical endometritis (SE) in dairy cows. We also characterised the treatment-related changes in the concentration of acute-phase proteins and metabolic variables in dairy cows affected by CE and SE. Cows of the SE and CE groups presented a significantly higher β-hydroxybutyrate (BHB), haptoglobin and total sialic acid (TSA) concentrations compared with a healthy group of animals. A significantly lower serum calcium concentration, and a significantly higher serum aspartate aminotransferase activity in the CE group, were observed when compared with SE and healthy groups. The comparison of parameters before treatment indicated that cows suffering from CE or SE with lower concentrations of hepatic and inflammatory markers showed a better response to further treatment, and endometritis was not detected in the second examination. Moreover, decreased concentrations of BHB, acute-phase proteins and hepatic markers were observed after successful treatment for endometritis in CE and SE cows. The results obtained in this study suggest that improved liver function and a decrease in the acute-phase protein concentration might favour the resolution of endometritis after treatment.