Denis Haine

Staphylococcus aureus is a bacterial pathogen causing bovine intramammary infections (IMIs) often leading to chronic clinical or subclinical mastitis. Predicting the outcome of S. aureus IMIs (duration and clinical vs subclinical) based on the characterization of isolates would help to make better case management decisions. For this purpose, 583 S....

Mastitis imposes considerable and recurring economic losses on the dairy industry worldwide. The main objective of this study was to estimate herd-level costs incurred by expenditures and production losses associated with mastitis on Canadian dairy farms in 2015, based on producer reports. Previously, published mastitis economic frameworks were use...

Using imperfect tests may lead to biased estimates of disease frequency and measures of association. Many studies have looked into the effect of misclassification on statistical inferences. These evaluations were either within a cross-sectional study framework, assessing biased prevalence, or for cohort study designs, evaluating biased incidence ra...

The primary objective of the current study was to evaluate cure rate following an early-lactation extended intramammary pirlimycin treatment on heifers naturally infected by Staphylococcus aureus. The secondary objective was to assess Petrifilm Staph Express (3M Microbiology, St. Paul, MN) count plate characteristics when used in a protocol for ear...

Using imperfect tests may lead to biased estimates of disease frequency and of associations between risk factors and disease. For instance in longitudinal udder health studies, both quarters at risk and incident intramammary infections (IMI) can be wrongly identified, resulting in selection and misclassification bias, respectively. Diagnostic accur...

The series of events leading to the decision to cull a cow is complex, involving both individual-level and herd-level factors. While the decision is guided by financial returns, it is also influenced by social and psychological factors. Research studies on the motivational and behavioural aspects of farmers’ decision utility are sparse, and nonexis...

Health disorders, such as milk fever, displaced abomasum, or retained placenta, as well as poor reproductive performance, are known risk factors for culling in dairy cows. Clinical mastitis (CM) is one of the most influential culling risk factors. However the culling decision could be based either on the disease status or on the current milk yield,...

The relationship between cows’ health, reproductive performance or disorders and their longevity is well demonstrated in the literature. However these associations at the cow level might not hold true at the herd level, and herd-level variables can modify cow-level outcomes independently of the cows’ characteristics. The interaction between cow-lev...

A retrospective cohort study was conducted using production and health records from Québec dairy herds which were integrated with the objectives of calculating different lifetime profitability measures and developing analyses of the impact of selected reproduction and health variables on profitability. The dataset for the study consisted of lifetim...

Several health disorders, such as milk fever, displaced abomasum, and mastitis, as well as impaired reproductive performance, are known risk factors for the removal of affected cows from a dairy herd. While cow-level risk factors are well documented in the literature, herd-level associations have been less frequently investigated. The objective of...

The objectives of this study were to: 1) quantify culling rates of Quebec dairy herds, and 2) investigate if Quebec dairy farms could be differentiated based on herd-level factors such as management, reproduction, production and health indices, and explore their relationship with herd culling rate.

While minimizing total losses (sum of production loss and disease control expenditures) is recognized to be the most profitable approach, dairy producers still have flexibility regarding the timing of their decisions, the liberty to make individual choices (e.g., genetic selection), or the handling of certain constraints (e.g., regulations, quotas,...

The regulatory limit in Canada for bulk tank somatic cell count (BTSCC) was recently lowered from 500,000 to 400,000 cells/mL. Herd indices based on changes in cow somatic cell count over 2 consecutive months (e.g., proportion of healthy or chronically infected cows, cows cured, and new intramammary infection rate) could be used as predictors for B...

Staphylococcus aureus is a significant pathogen frequently causing persistent intramammary infections (IMI) in dairy cows. We compared some genotypic and phenotypic characteristics of 285 strains collected from quarter milk samples from cows with persistent and nonpersistent subclinical IMI across Canada. Variable number of tandem repeats typing wa...

Abstract Text: Economic values were estimated by regressing profit, adjusted for opportunity cost, up to the end of the 4th lactation on EBVs, using random regressions within herd-year cohort of first calving. Kilograms Fat, kg Protein, milking speed, temperament, rump and conformation all had positive economic values, whereas herd life, angularity...

Abstract Text: In Quebec, management of dairy herds is affected by various combinations of milking systems (Milk Line, Milking Parlor or Milking Robot), housing systems (Tie-Stall or Free-Stall), and feeding systems (Traditional Feeding, Automatic Forage Distribution, Automatic Concentrate Distribution, Computerized Automatic Concentrate Distribu...

A culling rate> 30% in dairy cattle is common in United States and Canada, despite general recommendations to lower cull rates in order to save on replacement costs. Also, higher cull rates are sometimes viewed as a sign of management failure, but the association between culling and disease at the cow level may not hold true at the herd level. Ther...

Since August 2012, the upper tolerance limit for bulk-tank somatic cell count (BTSCC) in Canada is 400,000 c/mL. Among Quebec's dairy herds in 2011, 13% of BTSCC analyses exceeded that limit and were at risk of financial penalties. Herd indices on the basis of individual-cow somatic cell count (SCC) variations around a threshold of 200,000 c/mL bet...

Aims: Biofilm formation is important for the persistence of bacteria in hostile environments. Bacteria in a biofilm are usually more resistant to antibiotics and disinfectants than planktonic bacteria. Our laboratory previously reported that low concentrations of zinc inhibit biofilm formation of Actinobacillus pleuropneumoniae. The aim of this st...

Mastitis is the most common and detrimental infection of the mammary gland in dairy cows and has a major economic impact on the production of milk and dairy products. Bacterial mastitis is caused by several pathogens, and the most frequently isolated bacterial species are coagulase-negative staphylocci (CNS). Although CNS are considered minor masti...

Bacteriological culture (BC) is the traditional method for intramammary infection diagnosis but lacks sensitivity and is time-consuming. Multiplex real-time polymerase chain reaction (mr-PCR) enables testing the presence of several bacteria and reduces diagnosis time. Our objective was to estimate bacterial species-specific sensitivity (Se) and spe...

Major mastitis pathogens such as Staphylococcus aureus, Streptococcus agalactiae, Streptococcus uberis, Streptococcus dysgalactiae, and the coliforms are usually considered more virulent and damaging to the udder than minor mastitis pathogens such as Corynebacterium bovis and coagulase-negative staphylococci (CNS). The current literature contains s...

Bacteriological culture (BC) is the traditional method for intramammary infection diagnosis but lacks sensitivity and is time-consuming. Multiplex real-time polymerase chain reaction (mr-PCR) enables testing the presence of several bacteria and reduces diagnosis time. Our objective was to estimate bacterial species-specific sensitivity (Se) and spe...

The aim of the study was to assess the clinical efficacy, safety, and disease-modification effects of tramiprosate (homotaurine, ALZHEMED(TM)) in mild-to-moderate Alzheimer's disease (AD). Double-blind, placebo-controlled, randomized trial in 67 clinical centres across North America. Patients aged ≥ 50 years, with mild-to-moderate AD (Mini-Mental S...

Researching the impact and epidemiology of coagulase-negative Staphylococcus species (CNS) causing intramammary infections (IMI) require their identification at the species level. Gene sequencing is the gold standard but faster and less expensive methods could be useful. The Sherlock Microbial Identification System is an automated gas chromatograph...

To assess the effect of preservative-free dorzolamide-timolol on nonvisual symptoms and intraocular pressure (IOP) in newly diagnosed and untreated patients with open-angle glaucoma or ocular hypertension. This was a prospective, 8-week, open-label, Canadian multicenter study. All patients were treated with preservative-free dorzolamide-timolol for...

Tramiprosate (homotaurine, ALZHEMEDTM) was recently investigated for its efficacy, safety and disease-modification effects in a Phase III clinical study in mild to moderate Alzheimer's disease (AD) patients (the Alphase study). The primary cognitive endpoint measure of that study was the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS...

The efficacy, safety and disease-modification of tramiprosate (homotaurine)were investigated in a recently completed large-scale Phase III clinical study in patients with mild to moderate Alzheimer's disease (AD), the Alphase study. Disease-modification was assessed using longitudinal volumetric MRI (vMRI) measurements of the hippocampus in a subgr...

To evaluate the effectiveness of montelukast as add-on therapy for asthmatic patients who remain uncontrolled with low, moderate or high doses of inhaled corticosteroid monotherapy. An eight-week, multicentre, open-label, observational study. Of 320 patients enrolled, 288 (90.0%) completed the study. Of patients who had uncontrolled asthma symptoms...

AIM: To evaluate the effectiveness of montelukast as add-on therapy for asthmatic patients who remain uncontrolled with low, moderate or high doses of inhaled corticosteroid monotherapy. DESIGN: An eight-week, multicentre, open-label, observational study. RESULTS: Of 320 patients enrolled, 288 (90.0%) completed the study. Of patients who had uncont...

Our objective was to determine the seroprevalence of Hypoderma spp. and to develop a spatial model describing the risk surface of warble-fly infection in Belgian cattle herds (adjusting for herd size, herd type, local temperature, rainfall, relative air humidity and land-cover). This survey was carried out in 390 selected herds of all types (dairy,...