Pregnancy rate following post-insemination intrauterine treatment of endometritis in dairy cattle

Summary Of 1500 examined Holstein cows in milk, there were 315 cows with mucopurulent discharges at the time of insemination (21%). Twenty-four hours after insemination, the infected animals randomly received no treatment (group I, control, n = 93), intrauterine infusion of 1 g oxytetracycline (group II, n = 63) and intrauterine infusion of 5 million IU procain penicillin G sodium (group III, n = 159). First service conception rate following treatment was 48.3, 49.2 and 47.7% in groups I, II and III, respectively. In conclusion, treatment with either antibiotic had no advantage relative to the control on first service conception rate.     

Evaluation of the agar gel immunodiffusion test for diagnosis of subclinical paratuberculosis in cattle

Concurrent bacteriologic culture of feces and agar gel immunodiffusion (AGID) testing was performed on all cows and bred heifers over 14 months old in 10 dairy herds during a 32-month period to determine the effectiveness of the AGID test for the detection of subclinical paratuberculosis. Herds were sampled 5 times and, when possible, culled animals were tested again at slaughter. During 5 herd-wide samplings, Mycobacterium paratuberculosis was isolated from 139 fecal specimens obtained from 109 cattle. Results of the AGID test were simultaneously positive 40 of 139 times (28.8%). Thirty-six of the 109 cattle (33.0%) determined to be infected had a positive AGID test result at some point during the 5 herd-wide samplings. When results of tests performed at time of slaughter were included, 117 cattle were identified as infected by culture methods; 55 of these (47.0%) were AGID test-positive at some point during the study. The upper limit of the maximal false-positive rate for the AGID test was 2.1%. On the basis of colony counts from cultures, subclinically infected cows shedding higher numbers of M paratuberculosis in their feces were more likely to have positive AGID test results (P less than 0.0001). In known infected cattle, neither the culture nor AGID test results were consistently positive on repeated testing. Of 48 official calfhood paratuberculosis vaccinates tested as adults, 3 had positive AGID test results and in 1 of these, M paratuberculosis was also isolated from the feces, indicating that the rate of false-positive AGID test results in calfhood vaccinates is low.     

病原菌诊断技术及其在奶牛子宫内膜炎中的应用进展

病原菌感染可以引起动物多种疾病,给畜牧业造成严重的经济损失。子宫内膜炎是奶牛重要的繁殖疾病,多由病原菌混合感染所致。若能及时、准确地检测出引起子宫内膜炎的致病菌,对该病的综合防治至关重要。目前,有关奶牛子宫内膜炎病原菌诊断技术的报道很少,现对当前用于该病病原菌诊断的传统方法、免疫检测标记技术及分子生物学技术的研究进展进行综述,同时对各种诊断方法的优缺点进行了比较,并简要介绍这些诊断方法在奶牛子宫内膜炎中的应用情况,旨在为奶牛子宫内膜炎病原菌的诊断技术研究提供参考。     

Long-term alteration of follicular steroid concentrations in relation to subclinical endometritis in postpartum dairy cows

The focus of this study was to investigate the effect of subclinical endometritis (scEndo) on ovarian follicular steroid concentrations in early postpartum pasture-fed dairy cows. Mixed-age lactating dairy cows (n = 169) were examined to ascertain uterine health status on d 21 postpartum (±3 d). From this herd, a cohort of scEndo and uninfected cows (n = 47) were selected using uterine cytology to determine scEndo. To ensure cows with scEndo were selected for the study, a conservative threshold [>18% polymorphonuclear (PMN) cells among uterine nucleated cells] was chosen as a selection threshold. Ovarian follicular dynamics were assessed by ultrasonography on d 21, 42, and 63 postpartum. On the latter 2 d, all follicles >4 mm in diameter were ablated, and 4 d later, the largest (F1) and second largest (F2) follicles were measured and their follicular fluid aspirated. Hematological variables and plasma metabolites were measured also on these days to further characterize scEndo cows. On d 21, the prevalence of scEndo was approximately 9% in this herd; by d 42 infections had self-resolved in the majority (81%) of those cows classified as having scEndo on d 21. The scEndo cows had a delayed return to cyclicity; however, no effect was evident on ovarian follicle size or growth rate. Weeks after scEndo had self-resolved and cyclicity was restored, decreased (P = 0.07) testosterone and increased (P = 0.07) cortisol concentrations were evident in F1 follicles of scEndo compared with uninfected cows. Progesterone concentrations of F1 increased (P < 0.05) in 11- to 16-mm diameter follicles of scEndo cows, whereas estradiol, androstendione, and dehydroepiandrosterone concentrations were decreased (P < 0.05) in F1 8- to 10-mm diameter follicles of scEndo cows. These 3 steroids also differed (P < 0.05) between F1 follicle size categories of scEndo but not uninfected cows. On d 21, mean plasma albumin concentration was decreased (P = 0.02) in scEndo cows. In summary, early postpartum scEndo had surprisingly long-term influences on the steroid concentrations of ovarian follicles long after infections had self-resolved. This is likely to affect oocyte quality and may partially explain the reduced conception rates and longer interval between calving and conception that are often associated with scEndo, although more detailed investigations are required to substantiate this theory.     

Correlations of measurements of subclinical claw horn lesions in dairy cattle

Measurements were made of the extent of sole and white line lesions on the claws of 115 Holstein-Friesian cows on at least three and at most 16 occasions, and some cows were followed up to their third lactation. All the measurements were made between 12 weeks before calving and 45 weeks after calving. In total, 1016 repeated observations were made. Correlations were calculated between pairs of claws, between types of lesion (sole and white line), and between pairs of the different measurements (number of lesions, proportion of the claw affected, maximum severity score and proportion of the claw affected weighted for severity). The outer hind claws had the greatest extent of lesions of both types. Spearman correlation coefficients and confidence intervals measured the strength of the association. All the associations between claws were positive, suggesting that the lesions did not occur in isolation. Sole and white line lesions were not associated at individual observation points. Lesions on the left and right claws were markedly similar, except for sole lesions on the two inner hind claws, and for white line lesions on the two outer hind claws.     

Incidence of subclinical endometritis and its effects on reproductive performance of crossbred dairy cows

In dairy cattle, uterine infections are not life threatening and often unavoidable; however, they reduce fertility and increase the production costs of properties. The aim of this study was to evaluate the incidence of subclinical endometritis from 32 to 70 days in milk (DIM) and its effects on the reproductive performance of crossbred dairy cows. Lactating cows (Holstein/Gir; n?=?172), with no history of retained placenta, without clinical signs of uterine infection were used. The body condition score (BCS) was evaluated on a scale from 1 to 5. Ultrasound examination was performed to evaluate uterine lining and ovarian activity, while vaginal mucus was analyzed by gloved hand. The diagnosis of subclinical endometritis was performed by endometrial cytobrush technique. The samples were collected, stained, and examined microscopically; positive cases for subclinical endometritis were considered with the presence of ≥5 % of neutrophils. Later, the cows were submitted to conventional artificial insemination or timed artificial insemination. The incidence of subclinical endometritis in the herd was 26 %, and this was not affected by the season of calving, presence of corpus luteum, DIM, and parity. Cows with a BCS ≤2.50 had a higher incidence of subclinical endometritis. The conception rate to first insemination and pregnancy rate at 150 days postpartum were not influenced by the presence of subclinical endometritis in crossbred dairy cows.     

黑龙江地区奶牛子宫内膜炎病原菌的分离鉴定与药物敏感性试验

选取黑龙江地区奶牛场患子宫内膜炎奶牛51头,采取子宫分泌物,对其病原菌进行分离鉴定。试验共分离出菌种175株,其中主要病原菌为大肠杆菌、葡萄球菌、链球菌及蜡样芽孢杆菌,且大多数牛为混合感染。药敏试验表明,主要病原菌对环丙沙星、恩诺沙星与左氟沙星等药物敏感。     

金华地区奶牛子宫内膜炎病原菌的分离鉴定及药敏试验

本研究主要是通过对金华地区几个牛场进行的子宫内膜炎调查和采样,分析了金华地区奶牛子宫内膜炎发生的病原特征和相关的药敏试验结果,结果显示金华地区奶牛子宫内膜炎发病的主要病原菌有葡萄球菌、链球菌、肠杆菌科的细菌和绿脓杆菌等,并且多数呈混合感染。同时,药敏试验也证明目前多数病原菌对青霉素类药物已完全耐药,但对环丙沙星类药物有着较高的敏感性。     

Use of ultrasound in the reproductive management of dairy cattle

The significant decrease in fertility observed in dairy cattle during the last few decades and increasing requirements by the farmers have made a regular control of reproduction indispensable to urgently identify and solve potential problems affecting reproductive efficiency. Traditionally, the main diagnostic methods used for reproductive control in cattle included rectal palpation, inspection of vaginal discharge and vaginoscopy. Since the 1990 s, the use of ultrasound (US) has become a common diagnostic method as a result of the new advances made in the development of US scans: smaller size, high level of autonomy, high image quality and accessible prices. Ultrasound improves accuracy in the diagnoses of stages of the oestrous cycle, ovarian and uterine pathologies, and pregnancy diagnosis. In addition, it facilitates the diagnosis of alterations during pregnancy (embryo mortality, foetal malformations, etc.) and helps determining foetal sex from day 55 of pregnancy.     

中西医结合治疗奶牛子宫内膜炎

奶牛的子宫内膜炎是指子宫粘膜受到侵害而发生炎症。根据粘膜炎症的性质不同,将子宫内膜炎分为卡他性、脓性、卡他性脓性和坏死性子宫内膜炎。根据病程的长短可分为急性和慢性子宫内膜炎。慢性由急性转化而来,慢性炎症有时也可急性发作。子宫内膜炎常因炎症的扩散而引起子宫肌炎和子宫浆膜炎及盆腔炎、卵巢炎等。     

Prevalence of subclinical ketosis in dairy cattle in the Southwestern Iran and detection of cutoff point for NEFA and glucose concentrations for diagnosis of subclinical ketosis

Subclinical ketosis (SCK) is simply a condition marked by increased levels of circulating ketone bodies without the presence of the clinical signs of ketosis. Subclinical ketosis can cause economic losses through decreased milk production and association with preparturient diseases. Limited information is available regarding the prevalence of SCK in dairy herds in Southwestern Iran. The objectives of this study were (i) determination of the cutoff point of nonesterified fatty acids (NEFAs) and glucose concentrations for diagnosis of SCK using receiver operating characteristic (ROC) analysis, and (ii) determination of prevalence of subclinical ketosis in apparently healthy dairy cattle in Southwestern Iran. From October to December 2009, a total of 100 clinically healthy multiparous Holstein cows (3-8 years old) were randomly selected from 16 dairy herds around Kazerun, Fars Province, Iran. The cows had two-six lactations, with body weight ranging from 500 to 650 kg. Blood samples for each cow were taken at 2, 4 and 6 weeks post parturition and 3-4h after the morning feeding. The optimal cutoff point was set, by the ROC method, to >0.26 mmol/L for NEFA, and < 2.26 mmol/L for glucose with corresponding 82.54% sensitivity and 91.89% specificity for NEFA and 44.44% sensitivity and 78.38% specificity for glucose. Cows with BHB concentrations higher than 1200 μmol/L were classified as having SCK. In 2, 4 and 6 weeks post parturition 63%, 68% and 59% of the tested cows were subclinically ketotic. Overall, 97% of tested cows (97/100) were considered subclinically ketotic in at least one sample period. Thirty percent of tested cows (30/100) suffered from subclinical ketosis in all of the 2, 4 and 6 weeks postpartum. The results suggest that, a cut-off point of 0.26 mmol/L for NEFA concentrations can be used during early lactation for diagnosis of subclinical ketosis and making management decisions for prevention and treatment. Glucose cannot be a good criterion for diagnosis of SCK and it does not appear to be useful for monitoring subclinical ketosis.     

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.     

中药方剂治疗奶牛隐性乳房炎的疗效试验

乳房炎特别是隐性乳房炎是危害奶牛养殖业最常见的疾病之一,不仅影响产奶量,而且影响乳的品质[1]。近几十年来,抗生素在防治奶牛乳房炎方面发挥了重要作用,但临床治疗乳房炎常用的抗生素由于存在药物残留将逐渐被限用或禁用。中药是天然物质,含有多种生物有效成分,具有很好的抗菌活性[2]、消炎、不易产生耐药性、低毒、无残留或低残留等特点,兼有药物与营养剂双重功能。应用中药治疗奶牛乳房炎,已日益为国内外专家所关注。针对这一情况,本试验拟选用治疗乳房炎的中药方剂治疗奶牛隐性乳房炎以评价其治疗效果。1材料与方法1.1中药方剂黄芪、…     

Reproducibility of endometrial cytology using cytobrush technique and agreement for the diagnosis of subclinical endometritis between five predefined endometrial sites

The objectives of this study were as follows: (a) to assess the reproducibility of polymorphonuclear neutrophil (PMN) cell counts at five predefined endometrial sites (corpus uteri, left horn base, right horn base, left horn tip and right horn tip) and (b) to determine the agreement for the diagnosis of subclinical endometritis (SE) between the different endometrial sites. Forty milking cows between 28 and 34 days post‐partum were enrolled for endometrial sampling using cytobrush technique. Intraclass correlation coefficient (ICC) was calculated to evaluate the reproducibility of PMN counts at different sites. The right horn base was found to have the greatest agreement of PMN counts with the other endometrial sites (ICC = 0.66–0.85). Twenty‐eight of 40 cows showed no signs of clinical endometritis and were used for evaluation of agreement for the diagnosis of SE, analysed by using Cohen´s kappa (κ) statistics. Agreement for SE diagnosis with PMN cut‐off ≥5% was greatest between the right horn base and the right horn tip (κ = 0.84), and with PMN cut‐off ≥18% between the right horn base and left horn tip (κ = 1.0), respectively. The results indicate that the right horn base can be regarded as suitable for cytobrush sampling. The probability to detect an animal positive for SE (PMN ≥ 5%) with a single cytobrush sampling was 51.0%; thus, a second sampling is recommended to improve the accuracy.     

Evaluation of polymerase chain reaction diagnosis of Cryptosporidium spp in dairy cattle and wildlife

This study investigated the utility of the polymerase chain reaction (PCR) protocol as a screening test for Cryptosporidium spp in 125 fecal samples from dairy cattle and wild rodents. Samples initially examined by fecal flotation and ELISA were evaluated using four PCR protocols (18S SSU rRNA, TRAP-C2, HSP70, and COWP), and the relative accuracy and agreement of PCR protocols was assessed. Although PCR can be both highly sensitive and accurate, the ability of these protocols to accurately detect DNA in samples can vary. A combination of techniques may be the best choice for to screen samples for this parasite.     

Association between Coxiella burnetii shedding in milk and subclinical mastitis in dairy cattle

The objective of this research was to explore the potential association between Coxiella burnetii shedding in milk and chronic subclinical mastitis in dairy cattle. In two separate studies, we identified an association between PCR-based detection of C. burnetii in milk and chronic subclinical mastitis in lactating dairy cows. These studies were conducted in a commercial dairy herd where there was ongoing intensive monitoring of subclinical mastitis by aerobic bacteriology, but no prior knowledge or management of C. burnetii infections. In a case-control study, quarter level C. burnetii status determined by real-time quantitative PCR (RT-qPCR) was strongly associated with chronic subclinical mastitis as measured by milk somatic cell counts. In a subsequent cross sectional study, 147 (45%) of 325 lactating cows were positive for C. burnetii by RT-qPCR of composite milk samples. In a generalized linear model, accounting for the effect of covariates including aerobic intramammary infection status, C. burnetii PCR status was a significant predictor of linear somatic cell count score. In agreement with a small number of previous reports, this research provides evidence that there may be mammary gland specific manifestations of C. burnetii infections in dairy cattle.