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Short communication: Randomized controlled trial of intrauterine cephapirin treatment in cows of 100 days in milk or more affected by reproductive tract diseases
The objective of this study was to quantify the efficacy of a second intrauterine cephapirin treatment administered 14 d after the initial one on subsequent reproductive performance of postpartum dairy cows affected by purulent vaginal discharge (PVD) or endometritis (ENDO). In total, 4,140 Holstein cows from 30 commercial herds were enrolled in a randomized clinical trial. At 36 (±7) d in milk, cows were examined using the Metricheck device to diagnose PVD. An endometrial cytology sample was also collected from each cow to perform a leukocyte esterase test for diagnosing ENDO. Diagnosis of PVD and ENDO was done cow-side. Cows diagnosed with PVD or ENDO were assigned to receive 1 of 2 treatments: (1) a single intrauterine cephapirin infusion (500 mg of cephapirin benzathin; Metricure, Merck Animal Health, Kirkland, QC, Canada) at the time of initial examination or (2) a single intrauterine infusion at the time of initial examination and a second one 14 d later. Subsequent reproductive and culling events were collected until 200 d in milk. Statistical analyses were performed using univariable and multivariable mixed logistic regression models. In cows affected by PVD, a second intrauterine cephapirin infusion increased the pregnancy risk at first insemination in comparison with cows that only received one treatment (28.0 vs. 38.8%). In cows affected by ENDO, a second treatment also increased the pregnancy risk at first insemination compared with cows that only received one treatment (30.3 vs. 39.2%). Overall, these results demonstrate that administering a second intrauterine cephapirin infusion 14 d after the initial treatment in postpartum cows affected by PVD or ENDO did improve their subsequent reproductive performance.
The objectives of this observational study were to identify the optimal diagnostic criteria for purulent vaginal discharge (PVD) and cytological endometritis (ENDO) using vaginal discharge, endometrial cytology, and leukocyte esterase (LE) tests, and to quantify their effect on subsequent reproductive performance. Data generated from 1,099 untreated Holstein cows (28 herds) enrolled in a randomized clinical trial were used in this study. Cows were examined at 35 (±7) d in milk for PVD using vaginal discharge scoring and for ENDO using endometrial cytology and LE testing. Optimal combinations of diagnostic criteria were determined based on the lowest Akaike information criterion (AIC) to predict pregnancy status at first service. Once identified, these criteria were used to quantify the effect of PVD and ENDO on pregnancy risk at first service and on pregnancy hazard until 200 d in milk (survival analysis). Predicting ability of these diagnostic criteria was determined using area under the curve (AUC) values. The prevalence of PVD and ENDO was calculated as well as the agreement between endometrial cytology and LE. The optimal diagnostic criteria (lowest AIC) identified in this study were purulent vaginal discharge or worse (≥4), ≥6% polymorphonuclear leukocytes (PMNL) by endometrial cytology, and small amounts of leukocytes or worse (≥1) by LE testing. When using the combination of vaginal discharge and PMNL percentage as diagnostic tools (n = 1,099), the prevalences of PVD and ENDO were 17.1 and 36.2%, respectively. When using the combination of vaginal discharge and LE (n = 915), the prevalences of PVD and ENDO were 17.1 and 48.4%. The optimal strategies for predicting pregnancy status at first service were the use of LE only (AUC = 0.578) and PMNL percentage only (AUC = 0.575). Cows affected by PVD and ENDO had 0.36 and 0.32 times the odds, respectively, of being pregnant at first service when using PMNL percentage compared with that of unaffected cows; odds ratios were 0.33 and 0.69 for PVD and ENDO, respectively, when LE was used. Kappa value (agreement) of the pairwise comparison for the PMNL percentage and LE was 0.43. Vaginal discharge, endometrial cytology, and LE can be used to diagnose PVD and ENDO, and to predict pregnancy status at first service. The use of LE could be a good alternative to endometrial cytology for on-farm testing.
Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
The objectives of this study were to quantify the effect of an intrauterine infusion of cephapirin on reproductive performance at first service of postpartum dairy cows affected by purulent vaginal discharge (PVD) and cytological endometritis (ENDO) using different diagnostic strategies, and to determine if the presence of prolonged anovulation would influence the magnitude of treatment benefit. In total, 2,259 Holstein cows in 28 herds were enrolled in a randomized clinical trial. At 35 (±7) days in milk (DIM), cows were diagnosed with PVD using the Metricheck device (Simcro, Hamilton, New Zealand), with cytological endometritis using endometrial cytology (ENDO-CYTO), and with cytological endometritis using leukocyte esterase (ENDO-LE). Regardless of reproductive tract disease status, cows were randomly assigned to receive an intrauterine cephapirin infusion or to not be treated. Serum progesterone was measured at 35 and 49 (±7) DIM (14 d apart); cows were considered to have prolonged anovulation if progesterone was <1 ng/mL at both times. Reproductive events of cows were collected until 200 DIM. Statistical analyses were conducted using multivariable mixed logistic regression models. Intrauterine cephapirin treatment was associated with an increased first-service pregnancy risk in cows diagnosed with PVD (no treatment: 15.4%; treatment: 31.4%), ENDO-CYTO (no treatment: 16.2%, treatment: 24.4%), and ENDO-LE (no treatment: 15.8%; treatment: 25.1%), but not in cows unaffected by any form of reproductive tract disease (no treatment: 34.8%; treatment: 32.6%). Cephapirin treatment was also associated with an increased first-service reproductive performance in cows affected simultaneously by both PVD and ENDO-CYTO (no treatment: 8.7%; treatment: 23.4%). The effect of cephapirin treatment in anovular cows (no treatment: 21.0%; treatment: 26.4%) was numerically lower than in cyclic cows (no treatment: 22.7%; treatment: 34.1%). Overall, an intrauterine infusion of cephapirin improved first-service pregnancy risk in cows with postpartum reproductive tract disease and this effect was influenced by postpartum anovulation status.
Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
The objective of this study was to conduct a systematic and critical appraisal of the quality of previous publications and describe diagnostic methods, diagnostic criteria and definitions, repeatability, and agreement among methods for diagnosis of vaginitis, cervicitis, endometritis, salpingitis, and oophoritis in dairy cows. Publications (n = 1,600) that included the words "dairy," "cows," and at least one disease of interest were located with online search engines. In total, 51 papers were selected for comprehensive review by pairs of the authors. Only 61% (n = 31) of the 51 reviewed papers provided a definition or citation for the disease or diagnostic methods studied, and only 49% (n = 25) of the papers provided the data or a citation to support the test cut point used for diagnosing disease. Furthermore, a large proportion of the papers did not provide sufficient detail to allow critical assessment of the quality of design or reporting. Of 11 described diagnostic methods, only one complete methodology, i.e., vaginoscopy, was assessed for both within- and between-operator repeatability (κ = 0.55-0.60 and 0.44, respectively). In the absence of a gold standard, comparisons between different tests have been undertaken. Agreement between the various diagnostic methods is at a low level. These discrepancies may indicate that these diagnostic methods assess different aspects of reproductive health and underline the importance of tying diagnostic criteria to objective measures of reproductive performance. Those studies that used a reproductive outcome to select cut points and tests have the greatest clinical utility. This approach has demonstrated, for example, that presence of (muco)purulent discharge in the vagina and an increased proportion of leukocytes in cytological preparations following uterine lavage or cytobrush sampling are associated with poorer reproductive outcomes. The lack of validated, consistent definitions and outcome variables makes comparisons of the different tests difficult. The quality of design and reporting in future publications could be improved by using checklists as a guideline. Further high-quality research based on published standards to improve study design and reporting should improve cow-side diagnostic tests. Specifically, more data on intra- and interobserver agreement are needed to evaluate test variability. Also, more studies are necessary to determine optimal cut points and time postpartum of examination.
In the absence of prior knowledge about population relations, investigators frequently employ a strategy that uses the data to help them decide whether to adjust for a variable. The authors compared the performance of several such strategies for fitting multiplicative Poisson regression models to cohort data: 1) the "change-in-estimate" strategy, in which a variable is controlled if the adjusted and unadjusted estimates differ by some important amount; 2) the "significance-test-of-the-covariate" strategy, in which a variable is controlled if its coefficient is significantly different from zero at some predetermined significance level; 3) the "significance-test-of-the-difference" strategy, which tests the difference between the adjusted and unadjusted exposure coefficients; 4) the "equivalence-test-of-the-difference" strategy, which significance-tests the equivalence of the adjusted and unadjusted exposure coefficients; and 5) a hybrid strategy that takes a weighted average of adjusted and unadjusted estimates. Data were generated from 8,100 population structures at each of several sample sizes. The performance of the different strategies was evaluated by computing bias, mean squared error, and coverage rates of confidence intervals. At least one variation of each strategy that was examined performed acceptably. The change-in-estimate and equivalence-test-of-the-difference strategies performed best when the cut-point for deciding whether crude and adjusted estimates differed by an important amount was set to a low value (10%). The significance test strategies performed best when the alpha level was set to much higher than conventional levels (0.20).
The number needed to treat is a meaningful way of expressing the benefit of an active treatment over a control. It can be used either for summarising the results of a therapeutic trial or for medical decision making about an individual patient, but its use at the bedside has been impeded by the need for time consuming calculations. A nomogram has therefore been devised that will greatly simplify the calculations. Since calculations are now easy, the number needed to treat can be used to access the value of several interventions, although it does have its limitations. In particular it should not be used when it is not known whether the relative risk reduction associated with an intervention is constant for all levels of risk, or for periods of time longer than that studied in the original trials.
The objective of this study was to estimate the value of pregnancy for dairy cows. Effects of the stage of gestation, stage of lactation, lactation number, milk yield, milk price, replacement heifer cost, probability of pregnancy, probability of involuntary culling, and breeding decisions were studied. A bioeconomic model was used, and breeding and replacement decisions were optimized. A general Holstein herd in the United States was modeled. The average value of a new pregnancy was 555. The cost of a pregnancy loss typically increased with gestation length. Sensitivity analyses showed that an increased probability of pregnancy, an increased persistency of milk yield, and a smaller replacement heifer cost greatly reduced the average value of a pregnancy. The value of a new pregnancy was negative for relatively high-producing first-lactation cows when persistency of lactation and the probability of pregnancy were increased. Breeding was delayed when the value of pregnancy was negative. Changes in milk price, absolute milk yield, and probability of involuntary culling had less effect on the value of pregnancy. The value of pregnancy and optimal breeding decisions for individual cows were greatly dependent on the predicted daily milk yield for the remaining period of lactation. An improved understanding of the value of pregnancy may support decision making in reproductive management when resources are limited.
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This study aimed to (i) assess the prevalence of cytological endometritis ( CYTO ) diagnosed at artificial insemination ( AI ); (ii) evaluate the effect of CYTO on the pregnancy outcome of the same AI sample; and (iii) determine the risk factors associated with CYTO diagnosed at AI in repeat breeder ( RB ) dairy cows. We analysed the productive and reproductive performances of 146 RB Holstein‐Friesian cows. To obtain a CYTO sample at AI , we used the cytotape technique. Generalized mixed effect models were computed to find the risk factors associated with the pregnancy and CYTO outcome. Based on ≥1% PMN cut‐off point, the CYTO prevalence at AI in RB cows was 25.3%. The overall pregnancy at AI was 44.2%. The conception rate in CYTO ‐positive ( n = 37) RB cows was 29.7% versus 49.5% for CYTO ‐negative ( n = 109) cows. A RB cow diagnosed CYTO positive at AI had 0.47 [odds ratio ( OR )] odds to become pregnant in comparison with a CYTO ‐negative cow. Cows that produced more milk than their counterparts in this study had increased odds ( OR = 1.01) to be CYTO positive at AI . A novel risk factor positively associated with CYTO diagnosed at AI in RB cows was the level of daily milk urea ( OR = 1.11). To conclude, CYTO at the moment of AI had a significantly negative effect on the pregnancy outcome in RB dairy cows. However, as only one of fourth of RB cows is affected with CYTO at AI , it may not be considered a key element associated with the RB syndrome.
In the last decade, several new aspects of the inflammation of the bovine endometrium have been investigated and described, including a new definition of subclinical endometritis. This review summarizes the recent discussion about the definition, diagnosis and pathomechanism of subclinical endometritis. Subclinical endometritis also referred to as cytological endometritis is defined by findings of endometrial cytology, which is usually performed with the cytobrush-technique or by low-volume flushing of the uterus. The sampling procedure is minimally invasive and has no negative impact on subsequent conception rate. The suggested threshold value for polymorphonuclear cells (PMN) as diagnostic for subclinical endometritis depends on the time postpartum and varies from 5 to 18%. It has also been shown that a general threshold of 5% PMN is eligible for all cows between 21 and 62 days postpartum. Accuracy and repeatability of counting PMN under the microscope have been evaluated and can be regarded as reliable. The impact of subclinical endometritis on reproductive performance is characterized by decreased conception rates, and prolonged days to first service and days open. In addition, it has been demonstrated that subclinical endometritis has an impact on survival and quality of the embryo. Some studies, however, did not confirm this negative effect of subclinical endometritis on fertility. More detailed analyses of the cytobrush samples revealed higher mRNA expression of several cytokines in cows with subclinical endometritis compared with healthy cows, and contributed to the understanding of detrimental effects of subclinical endometritis on fertility. In contrast to clinical endometritis, there are no predominant bacteria related to subclinical endometritis, but associations between the presence of α-hemolytic streptococci and Trueperella pyogenes and subclinical endometritis have been found. For the treatment of subclinical endometritis, intrauterine infusions with cephapirin as well as the administration of PGF2α have been recommended. Other studies, however, did not confirm the efficiency of these treatments.
The objectives of this study were to quantify the herd-level prevalence of postpartum diseases in a large number of dairy farms, and to identify prevalence alarm levels of these diseases based on association with a low prevalence of success at first service, with a high prevalence of pregnancy loss following pregnancy diagnosis at first service, and with a high prevalence of postpartum culling. A total of 126 commercial dairy herds were enrolled in this cohort study, and the herd was the unit of interest. Twenty cows from every herd were enrolled during the study period (a total of 2,520 lactating cows in the study). Cows were diagnosed with hyperketonemia, retained placenta, displaced abomasum, purulent vaginal discharge, cytological endometritis, leukocyte esterase endometritis, and prolonged anovulation. The prevalence of each of these diseases was computed for every herd. The study outcomes were the prevalence of success at first service, the prevalence of pregnancy loss following pregnancy diagnosis at first service, and the prevalence of postpartum culling (≤60 d in milk). Descriptive statistics of disease and outcome prevalence were computed. Logistic regression models were used to identify prevalence alarm levels associated with poor outcome prevalence. Median herd prevalence for hyperketonemia, retained placenta, displaced abomasum, purulent vaginal discharge, cytological endometritis, leukocyte esterase endometritis, and prolonged anovulation were 18.8, 4.9, 4.0, 5.0, 29.4, 43.8, and 35.2%, respectively. Herds were defined as having low prevalence of success at first service if <40.0%, as having a high prevalence of pregnancy loss if ≥6.3%, and as having a high prevalence of postpartum culling if ≥13.3%. Risk factors for herds having a low prevalence of success at first service were ≥11.8% hyperketonemia, ≥5.0% purulent vaginal discharge, ≥18.8% cytological endometritis, ≥35.3% leukocyte esterase endometritis, ≥21.0% prolonged anovulation, and ≥4.0% of displaced abomasum. Risk factors for herds having a high prevalence of pregnancy loss were ≥5.0% purulent vaginal discharge and ≥4.9% retained placenta. Risk factors for herds having a high prevalence of postpartum culling were ≥23.1% hyperketonemia, ≥4.9% retained placenta, and ≥4.0% displaced abomasum. Overall, postpartum diseases were prevalent in these dairy herds and alarm levels were identified as risk factors for poor reproductive performance and increased culling.
The objective was to compare a leukocyte esterase (LE) test with endometrial cytology (EC) for diagnosis of subclinical endometritis in dairy cows. The relationship between subsequent fertility and the uterine (Ut) and cervical (Cx) leukocyte esterase activity was determined by the odds of pregnancy by 90 days in milk (DIM). Holstein cows (N = 218) without clinical endometritis and between 21 and 47 DIM from five commercial dairy herds were sampled for uterine and cervical leukocyte esterase activity and EC by cytobrush. To test the effect of time, cows were grouped into early (21-31 DIM) and late (32-47 DIM) animals. There was a slight agreement between UtLE and CxLE (weighted κ = 0.37). The percentage of neutrophils was correlated with esterase score either from the uterus (UtLE; P = 0.0001) or cervix (CxLE; P = 0.002). The percentage of neutrophils on EC (P < 0.001), the UtLE score (P < 0.0001), and the CxLE (P = 0.0009) diminished as DIM increased. Neither CxLE nor UtLE were statistically associated with pregnancy at 90 DIM. However, between 32 and 47 DIM, the percentage of neutrophils on EC and odds of pregnancy at 90 DIM were associated (P = 0.04). For the same interval, based on receiver/response operating characteristics analysis, the optimal cutoff was >6.7% neutrophils to classify cows with subclinical endometritis. In conclusion, uterine LE activity was correlated with percentage of neutrophils as determined by EC, but not with odds of pregnancy. Subclinical endometritis (>6.70% neutrophils) diagnosed by EC between 32 and 47 DIM was associated with reduced odds of pregnancy.
The objectives of this observational study were to determine and compare diagnostic criteria for postpartum endometritis in dairy cows. Data generated from 1,044 Holstein cows (6 herds) enrolled in a randomized clinical trial were used. Cows were examined for endometritis at 35±3 d (exam 1) and 56±3 d (exam 2) after parturition, using endometrial cytology (cytobrush technique), vaginal discharge scoring (Metricheck device; Simcrotech, Hamilton, New Zealand), and cervical diameter measurement (transrectal palpation). Reproductive data were recorded until 200 d after parturition. Diagnostic criteria for cytological and clinical endometritis were determined based on detrimental effect on subsequent reproductive performance, using logistic regression and Cox proportional hazard models accounting for the effect of herd clustering. Comparison of diagnostic criteria was performed using endometrial cytology as reference test or by quantifying the agreement between diagnostic approaches. At exam 1, diagnostic criteria were ≥6% polymorphonuclear cells and mucopurulent or worse (purulent or foul) vaginal discharge for cytological and clinical endometritis, respectively. At exam 2, diagnostic criteria were ≥4% polymorphonuclear cells and mucopurulent or worse vaginal discharge for cytological and clinical endometritis, respectively. Cows were classified as having cytological endometritis only, clinical endometritis only, or both cytological and clinical endometritis. Prevalence at exam 1 was 13.5, 9.4, and 5.8% for cytological endometritis only, clinical endometritis only, and both cytological and clinical endometritis, respectively. The detrimental effects of cytological and clinical endometritis on reproductive performance were additive. Among cows with clinical endometritis, only 38 and 36% had cytological endometritis at exam 1 and exam 2, respectively. Combination of diagnostic criteria improved neither the accuracy for predicting cytological endometritis nor the agreement between cytological and clinical endometritis. Overall, these results suggested that cytological and clinical endometritis may represent different manifestations of reproductive tract disease. They also suggested that use of the terminology clinical endometritis may not be accurate and that purulent vaginal discharge may be more descriptive.
The objective of this field trial was to compare the effect of intrauterine (i.u.) antibiotic or intramuscular (i.m.) prostaglandin F2 alpha (PGF2 alpha) on time to pregnancy in dairy cows diagnosed with clinical endometritis between 20 and 33 days in milk (DIM). The case definition of endometritis was the presence of purulent uterine discharge or cervical diameter > 7.5 cm, or the presence of muco-purulent discharge after 26 DIM. There were 316 cows with endometritis from 27 farms assigned randomly within herd to receive 500 mg of cephapirin benzathine intrauterine (i.u.), 500 micrograms of cloprostenol i.m., or no treatment. The rate of resolution of clinical signs 14 d after treatment was 77% and was not affected by treatment. Reproductive performance was monitored for a minimum of 7 mo after treatment. Survival analysis (multivariable proportional hazards regression) was used to measure the effect of treatment on time to pregnancy. There was no benefit of treatment of endometritis before 4 wk postpartum. Administration of PGF2 alpha between 20 and 26 DIM to cows with endometritis that did not have a palpable corpus luteum was associated with a significant reduction in pregnancy rate. Between 27 and 33 DIM, cows with endometritis treated with cephapirin i.u. had a significantly shorter time to pregnancy than untreated cows (hazard ratio = 1.63). In this time period, there was no difference in pregnancy rate between PGF2 alpha and untreated cows, but the difference in pregnancy rate between cows treated with cephapirin i.u. and with PGF2 alpha was not statistically significant. Treatment of postpartum endometritis should be reserved for cases diagnosed after 26 DIM, based on criteria that are associated with subsequent pregnancy rate.
The objectives of this study were to validate diagnostic criteria for clinical endometritis in postpartum dairy cows and to measure the impact of endometritis on reproductive performance. Data were collected from 1865 cows in 27 herds, including history of dystocia, twins, retained placenta, or metritis. All cows were examined once between 20 and 33 d in milk (DIM) including external inspection, vaginoscopy, and transrectal palpation of the cervix, uterus, and ovaries. All cows were followed for a minimum of 7 mo or until pregnancy or culling. Survival analysis was used to derive a case definition of endometritis based on factors associated with increased time to pregnancy. The significance of clinical findings depended on the interval postpartum when examination took place. The presence of purulent uterine discharge or cervical diameter > 7.5 cm after 20 DIM, or mucopurulent discharge after 26 DIM identified cows with clinical endometritis. Given vaginoscopy, no diagnostic criteria based on palpation of the uterus had predictive value for time to pregnancy. The prevalence of clinical endometritis was 16.9%. Vaginoscopy was required to identify 44% of these cases. Accounting for parity, herd, and ovarian status, cows with clinical endometritis between 20 and 33 DIM had a hazard ratio of 0.73 for pregnancy (took 27% longer to become pregnant), and were 1.7 times more likely to be culled for reproductive failure than cows without endometritis.
The objectives of the study were to validate the use of endometrial cytology (EC) and ultrasonography (US) to diagnose subclinical endometritis in clinically normal postpartum dairy cows, and to measure the impact of subclinical endometritis on reproductive performance. Holstein cows from two dairy farms were examined at Visit 1 (V1) at 20-33 days in milk (DIM), and clinically normal cows (n = 228), based on the absence of abnormal discharge on external inspection and vaginoscopy, were selected. The reproductive tract of selected cows was evaluated by transrectal palpation, US and EC. All cows in the study were re-examined at Visit 2 (V2) at 34-47 DIM (2 weeks after V1) and were subsequently followed for a minimum of 8 months (until pregnant or culled). Survival analysis was used to derive a case definition of subclinical endometritis, based on factors associated with decreased relative pregnancy rate. Positive EC at V1 (>18% polymorphonuclear leukocytes; PMN) or fluid in uterus at V1 (FIU1) were associated with a significant reduction in the relative pregnancy rate and identified cows with subclinical endometritis. Similarly, a positive EC (>10% PMN) at V2 or fluid in the uterus at V2 (FIU2), identified cows with subclinical endometritis. Cows with subclinical endometritis at V1 and at V2 had a relative pregnancy rate of 41 and 51% (hazard ratio for pregnancy of 0.59 and 0.49), respectively, compared to cows without subclinical endometritis. Given EC or US findings, no diagnostic criteria based on transrectal palpation of the uterus had predictive value for risk of pregnancy. In conclusion, subclinical endometritis, diagnosed by EC or US, was associated with reduced relative pregnancy rate.
Hostein cows (n=141) in five commercial dairy herds in central New York were examined for endometritis by examination of endometrial aspirates for presence of inflammatory cells, principally neutrophils, by endometrial cytology at 40-60 days postpartum. The prevalence of cytologically-diagnosed endometritis was 53%; within herds the prevalence varied from 37 to 74% (P=0.02). There was excellent agreement between two examiners (Kappa=0.864; P<0.0001). Parity did not influence prevalence of endometritis (P=0.53). Cytologically diagnosed endometritis was associated with profoundly impaired reproductive performance; Kaplan-Meier survival analysis revealed lower overall pregnancy rate (P<0.0001). Median days open was 206 for cows with endometritis and 118 for cows free of the condition. Overall, 76% of cows in this study became pregnant by 300 days postpartum; 63% of cows with endometritis and 89% of cows without endometritis were confirmed pregnant by 300 days postpartum (P<0.003). (For these two groups, 69, and 90% respectively, became pregnant during the duration of the study). Pregnancy to first service percentage was lower (11 versus 36%; P=0.001) for cows with than without endometritis, and these cows required more services before 50% became pregnant (3 versus 2; P=0.006). In a second study using 22 cows in a university-owned herd, the prevalence of cytological evidence of inflammation was 100% at 2 weeks postpartum, and dropped to 89, 58, and 41% at 4, 6, and 8 weeks, respectively. Endometritis diagnosed by endometrial cytology late in the voluntary waiting period was highly prevalent and exerted a profoundly detrimental effect on subsequent reproductive performance, making this condition potentially extremely costly to the North American dairy industry.
Endometritis reduces reproductive performance in dairy cattle. Diagnosis of endometritis is undertaken using a variety of techniques including vaginoscopy, manual examination, cytology and ultrasonography. The current studies compared a novel test device (“metricheck”) that is inserted into the vagina with vaginoscopy and then examined the relationship between the metricheck test score at 35 days before the start of the seasonal breeding programme and subsequent reproductive performance. Cows (n = 191; Study 1) with a history of a peripartum disease were examined by both vaginoscopy and the metricheck device and any material viewed within the vagina (using vaginoscopy) or retrieved (by the metricheck device) was scored on a 0 (no material) to 5 (grossly purulent and with an odour) scale. Within each herd the order of examination was randomized with sequentially presented pairs of cows. All cows (n = 2793; Study 2) from nine herds were examined and scored using the metricheck device 35 days before the start of the seasonal breeding programme. All cows were pregnancy tested to determine date of conception.
Based on previous research, we hypothesized that Cosynch at 72 h [GnRH-7 d-PGF(2alpha)-72 h-GnRH + artificial insemination (AI)] would result in a greater number of pregnancies per AI (P/AI) than Cosynch at 48 h. Further, we hypothesized that P/AI would be improved to a greater extent when GnRH was administered at 56 h after PGF(2alpha) before AI at 72 h due to a more optimal interval between the LH surge and AI. Nine hundred twenty-seven lactating dairy cows (n = 1,507 AI) were blocked by pen, and pens rotated through treatments. All cows received GnRH followed 7 d later by PGF(2alpha) and then received one of the following: 1) GnRH + timed AI 48 h after PGF(2alpha) (Cosynch-48); 2) GnRH 56 h after PGF(2alpha) + timed AI 72 h after PGF(2alpha) (Ovsynch-56); or 3) GnRH + timed AI 72 h after PGF(2alpha) (Cosynch-72). Pregnancy diagnoses were performed by ultrasound at 31 to 33 d post-AI and again at 52 to 54 d post-AI. Overall P/AI were similar for the Cosynch-48 (29.2%) and Cosynch-72 (25.4%) groups. The Ovsynch-56 group had a greater P/AI (38.6%) than Cosynch-48 or Cosynch-72. Presynchronized first-service animals had greater P/AI than cows at later services in Cosynch-48 (36.2 vs. 23.0%) and Ovsynch-56 (44.8 vs. 32.7%) but not in Cosynch-72 (24.6 vs. 26.2%). Similarly, primiparous cows had greater P/AI than multiparous cows in Cosynch-48 (34.1 vs. 22.9%) and Ovsynch-56 (41.3 vs. 32.6%), but not Cosynch-72 (29.8 vs. 25.3%). In conclusion, we found no advantage to Cosynch at 72 h vs. 48 h. In contrast, we found a clear advantage to treating with GnRH at 56 h, 16 h before a 72-h AI, probably because of more-optimal timing of AI before ovulation.
| CEPHAPIRIN TREATMENT EFFECT IN COWS ≥ 100 DIM JDS Communications TBC; TBC of dairy cows
- Dubuc
Dubuc et al. | CEPHAPIRIN TREATMENT EFFECT IN COWS ≥ 100 DIM
JDS Communications TBC; TBC
of dairy cows. Theriogenology 64:1879-1888. https: / / doi.org/ 10.1016/ j
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