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De Boer M.W.,Cognosco | De Boer M.W.,Massey University | LeBlanc S.J.,University of Guelph | Dubuc J.,University of Montreal | And 5 more authors.
Journal of Dairy Science | Year: 2014

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. © 2014 American Dairy Science Association. Source

McDougall S.,Cognosco | Heuer C.,Massey University | Morton J.,Jemora Pty Ltd. | Brownlie T.,Cognosco
Animal | Year: 2014

There has been a long history of herd health and production management programmes in many dairy industries around the world, but evidence for the efficacy of such programmes is limited. In response to a perceived decline in fertility of dairy cows, a herd reproductive management programme (InCalf) was introduced in New Zealand in 2007. This programme uses a management cycle approach that includes an assessment of the current herd status, identification of areas for improvement, development of a plan, implementation of this plan and finally a review process. The programme uses facilitators who work with farmers either in a one-to-one manner or in a formalised group setting that involves a series of meetings over a 12-month period (the farmer action group). The hypothesis that involvement in a reproductive management programme would improve herd reproductive performance was tested using a herd-level controlled randomised study (the National Herd Fertility Study) involving herds in four geographic regions of New Zealand over 2 years. Within each region, herds were ranked on the basis of the 6-week in-calf rate (i.e. the proportion of the herd pregnant in the first 6 weeks of the seasonal breeding programme) in the year preceding commencement of the study and then randomly assigned to be involved in a farmer action group or left as untreated controls. The key outcome variable of the study was the 6-week in-calf rate. Pregnancy diagnosis was undertaken at 12 weeks after the start of the seasonal breeding programme, which allowed determination of conception dates and hence calculation of the 6-week in-calf rate. Additional measurements including heifer live weight and body condition score (pre-calving and pre-mating) were undertaken to test whether treatment resulted in measurable changes in some of the key determinants of herd reproductive performance. Involvement in the farmer action group of InCalf resulted in a 2 percentage point increase in the 6-week in-calf rate (P=0.05). The following additional observations were made in herds involved in the farmer action group relative to control herds: heifers had live weight closer to target; the pre-mating body condition score of cows was higher; and oestrous detection rates were higher. It was concluded that involvement in this herd reproductive management programme improved reproductive outcomes in this New Zealand study. However, to achieve substantial improvements in herd reproductive performance at the regional or national level a greater response to the programme and a high uptake of such programmes is required, as well as use of other industry-level tools such as genetic management programmes. © 2014 The Animal Consortium. Source

Compton C.W.R.,Cognosco | Young L.,Agrihealth Ltd | McDougall S.,Cognosco
New Zealand Veterinary Journal | Year: 2015

AIMS: To determine the effectiveness of intra-rumenal controlled release capsules (CRC) containing 32 g of monensin administered pre-calving to reduce the cumulative incidence of subclinical ketosis (SCK) in mainly pasture-fed dairy cows. METHODS: Cows (n=837) due to calve in the first 6 weeks of the spring calving period were enrolled from four commercial herds in the Waikato region of New Zealand in a blinded, randomised, negative-controlled field trial. Three weeks before the start of the calving period cows were randomly allocated to receive either no treatment (control) or a single CRC containing monensin and then blood sampled on two occasions, 7 days apart within 12 days following calving for measurement of concentrations of beta hydroxybutyrate (BHBA) in blood. Cows were diagnosed with SCK if the concentration of BHBA in blood in either of these samples was ≥1.2 mmol/L. RESULTS: Fewer treated cows were diagnosed with SCK within 12 days post-calving than control cows (144/340 (42.4%) vs. 192/336 (57.1%); p<0.001). There was no interaction between treatment group and age, breed or herd of origin. From the final multivariable model it was estimated that treatment with CRC containing monensin reduced the absolute cumulative incidence of SCK by 17.9 (95% CI=9.2–25.8)% compared to no treatment. CONCLUSIONS: Treatment with a CRC containing monensin >10 days prior to calving reduced the cumulative incidence of SCK of pasture-based dairy cows in commercial dairy herds within 12 days post-calving. CLINICAL RELEVANCE: Administration pre-calving of an intra-rumenal bolus containing monensin can be considered as one of a range of management options for the control of SCK in early lactation. © 2015 New Zealand Veterinary Association. Source

McDougall S.,Cognosco | Compton C.W.R.,Cognosco
Theriogenology | Year: 2013

The objective was to evaluate the efficacy and economic benefits of three synchrony programs in 1137 heifers from 10 pasture-based dairy herds. Heifers were randomly assigned to one of three treatments within each herd on Day -13 (Day 0 = start of the breeding program). They were treated with: (1) PGF2α on Days -13 and -2, with AI after detection of estrus between Days 0 and 3 (Double PG); (2) GnRH, PGF2α, and GnRH on Days -9, -2, and 0, respectively, with placement of an intravaginal progesterone (P4)-releasing device between Days -9 and -2, and set time AI on Day 1 (GPG + P4); or (3) same as the GPG + P4 group but with the set time AI on Day 0 (Cosynch + P4). Plasma P4 concentrations were determined on Days -20 and -13 to determine pubertal status. The Cosynch + P4 treatment had a higher (P < 0.05) conception rate to AI (57% vs. 47% vs. 48% for Cosynch + P4, GPG + P4, and Double PG, respectively), 21-day in-calf rate (76% vs. 72% vs. 63% for Cosynch + P4, GPG + P4, and Double PG), and a shorter median interval from the start of the breeding program to conception (0, 14, and 19 days for Cosynch + P4, GPG + P4, and Double PG). Heifers that had reached puberty before breeding, compared with those that had not, had higher (P < 0.05) in-calf rates to AI (53% vs. 47%) at 21 days (74% vs. 64%) and at 42 days (91% vs. 84%). Pubertal status was associated with herd, breed, age, and body condition score at the start of mating (P < 0.05). A partial budget model demonstrated that, compared with the Double PG program, there was an economic benefit from the Cosynch + P4 (mean, NZ$25.73; 95% confidence interval, 2.99-50.69), but not the GPG + P4 program (mean, NZ$-0.65; 95% confidence interval, -21.87 to 21.58). We concluded that the Cosynch + P4 program resulted in the highest fertility and economic benefit of the three programs evaluated, and that reproductive response was affected by pubertal status. © 2013 Elsevier Inc. Source

de Boer M.,Cognosco | de Boer M.,Massey University | Buddle B.M.,Agresearch Ltd. | Heuer C.,Massey University | And 4 more authors.
Theriogenology | Year: 2015

Reproductive tract bacterial infections, particularly those caused by Escherichia coli and Trueperella pyogenes, can have a negative impact on reproductive performance. It has been hypothesized that the presence of E coli early postpartum may increase the risk of isolation of T pyogenes later postpartum. The objective of the present study was to examine associations between intrauterine bacterial infections with E coli and T pyogenes and any bacterial growth (irrespective of bacterial species), purulent vaginal discharge (PVD), cytologic evidence of endometritis (an increased proportion of polymorphonuclear cells [PMNs]), and reproductive performance. Dairy cows (n=272) from six herds were examined at Days 0 (median, 2days in milk), 21 and 42 postpartum. From each cow two intrauterine samples were collected via triple-guarded cytobrush at Days 0 and 21. The first cytobrush was used for bacteriologic culture. Escherichia coli and T pyogenes were isolated by culture, and E coli isolates were assigned to one of four phylogenetic groups using a two-step triplex polymerase chain reaction. In addition, T pyogenes was confirmed by polymerase chain reaction. The second cytobrush was used to prepare a cytology slide. Nucleated cells (n=200) were categorized as epithelial cells, PMNs, or macrophages. Cows were also assessed for body condition score, PVD score, the presence of a CL, and pregnancy. Statistical analysis was performed using multivariable models. There was no association between the presence of Ecoli at Day 0 and probability of isolation of T pyogenes 3weeks later; however, E coli positive cows at Day 0 were more likely to be diagnosed with E coli at Day 21 (relative risk [RR]=2.0, P<0.01). Escherichia coli at Day 0 or T pyogenes at Day 21 increased the risk of PVD diagnosis 3weeks later (RR=1.9; P=0.04 and RR=3.0; P=0.05, respectively). Cows with any bacterial growth at Day 21, irrespective of species, were less likely to conceive within 3weeks after the start of the seasonal breeding program (RR=0.8; P=0.05). Interestingly, cows with 25% PMNs or greater at Day 0 had shorter time to pregnancy (hazard ratio=1.32; P=0.05). Intrauterine bacterial infection may impair reproductive performance but the presence of E coli was not associated with isolation of T pyogenes 3weeks later. Increased endometrial flux of PMNs in cows early postpartum may be a physiological process and improve reproductive performance. © 2015 Elsevier Inc. Source

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