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AIM To determine the prevalence of Mycobacterium avium subsp. paratuberculosis (Map) infection in wildlife, in pastoral landscapes with a recent history of clinical Johne's disease in livestock. METHODS A total of 449 wild mammals and birds from three farms in the South Island of New Zealand with recent histories of clinical Johne's disease in their deer(More)
OBJECTIVE To determine bovine fetal characteristics significantly associated with increasing gestational age as measured via transcutaneous ultrasonography over the right flank. METHODS The length of gestation at date of pregnancy diagnosis via transcutaneous and transrectal ultrasonography was determined for 224 dairy cattle by estimation from subsequent(More)
AIM To estimate the prevalence of Mycobacterium avium subsp. paratuberculosis (Map) in farmed deer with no gross post-mortem evidence of Map infection slaughtered in New Zealand, and to assess predictors of infection. METHODS Mesenteric lymph node (MLN) samples (n = 251) were collected from 60 lines of deer presented at two slaughterhouses in the North(More)
OBJECTIVE To investigate the practical application and image quality of transcutaneous ultrasonography across the right flank for the diagnosis of mid- to late-gestation in cattle. PROCEDURE Dairy cows of known pregnancy status were used to establish criteria for the identification of mid- to late-stage pregnancy by transcutaneous ultrasonography. Factors(More)
AIM To assess the effect of vaccination against paratuberculosis (Johne's disease) on reactivity to diagnostic tests for bovine tuberculosis (Tb) in deer exposed to natural challenge with Mycobacterium avium subsp. paratuberculosis (Map), and to investigate Map infection as a factor in Tb test cross-reactivity at the herd level. METHODS In Study 1,(More)
AIMS To assess the effect of two temperatures (ambient temperature and 4°C), three preservation methods (no preservative, yoghurt and potassium sorbate), and two periods of storage (3 and 7 days) on Brix and total bacterial and coliform counts of colostrum collected from New Zealand dairy farms. METHODS One litre of colostrum destined to be fed to newborn(More)
AIMS To describe colostrum quality in spring-calving dairy herds in New Zealand, in terms of Brix, pH and total and coliform bacterial counts and to investigate associations between farm management practices and these measures of colostrum quality. METHODS In June 2015, commercial dairy farms (n=105), located in North and South Islands of New Zealand,(More)
AIMS The primary objective of this study was to describe the reproductive performance of a selection of New Zealand dairy herds in 2009/10 and 2010/11. A secondary objective was to explore associations between a number of biophysical and socio-demographic herd-level variables and herd-level reproductive outcomes. METHODS Seasonal-calving, pasture-based(More)
AIMS To develop and validate criteria for identification of abnormal lymph nodes (LN) at commercial slaughter, for the purpose of national surveillance for Mycobacterium avium subspecies paratuberculosis (Map) in New Zealand farmed deer. This included estimation of the predictive value of abnormal LN for Map infection; a standard circumference cut-point for(More)
AIMS To assess the sensitivity (Se), specificity (Sp) and level of agreement in the detection of abnormal deer mesenteric lymph nodes (MLN) by official assessors (meat inspectors) for the purpose of slaughter premise surveillance for Johne's disease in New Zealand farmed deer. METHODS To determine Se and Sp, four meat inspectors in two commercial deer(More)