Sébastien Buczinski

Université de Montréal | UdeM · Faculty of Veterinary Medicine

Diagnostic tests are performed daily by bovine practitioners at the individual and population level. At the individual level, they help not only for making a diagnosis, but can also serve to rule in or rule out a specific condition, monitor treatment response, establish a prognosis, or to determine infection status. Performing an individual diagnos...

Inadequate transfer of passive immunity (ITPI) is major risk for mortality, morbidity and decreased growth performance in dairy and beef calves. Refractometry method is used in estimating ITPI in dairy and beef calves but studies evaluating refractometers for Simmental dairy calves are limited. The objectives of this study were determining the accu...

Background Assessing the inadequate transfer of passive immunity (ITPI) in beef calves is crucial because calves with ITPI are at high risk for morbidity and mortality. Objectives The aim of this study was to determine the accuracy of digital Brix (D-BRIX) and digital serum total protein (D-STP) refractometers to estimate different passive immunity...

Active infectious bovine respiratory disease (BRD) is an infection of the airways that needs to be diagnosed correctly so that appropriate treatment can be initiated. The simplest and most practical test to detect active BRD in dairy calves raised for veal is the detection and interpretation of clinical signs by producers or technicians. However, t...

The objective of the present study was to quantify the relationships between prepartum nonesterified fatty acid (NEFA) concentrations and the development of subsequent diseases or culling and to identify the optimal thresholds allowing identification of animals at high risk of developing postpartum diseases or being culled. A total of 1,299 Holstei...

Inadequate transfer of passive immunity (ITPI) in newborn dairy calves remains an important risk factor for mortality and morbidity. Most available studies are focused on calves delivered and raised on the same farms. This setting is far different from calves transported and commingled from different farms to be raised as veal or for other purposes...

1.Objectives: Commingled dairy calves undergo different health problems which lead to a high antimicrobial treatment rate specially in calves with inadequate transfer of passive immunity (ITPI). The aim was to describe, in multi-source commingled dairy calves raised for veal or other purposes, the association between ITPI and important health outco...

Bovine respiratory disease (BRD) is a multifactorial disease which causes short- and long-term negative effects. Early detection is crucial for a prompt response to therapy, as well as to decrease mortality risk. Clinical scoring systems have been developed mostly in North America for screening calves at risk or suspected of having BRD, and these t...

Multiple treatments for hyperketonemia have been studied, and although propylene glycol has been the most constantly reported as successful in mitigating the effects of this condition, a recent study showed that a subpopulation of cows affected by hyperketonemia and hypoglycemia could benefit from a combined treatment of propylene glycol and insuli...

Calves born on Eastern Canadian dairy farms that are not kept in the herds are traditionally sold through auction markets and are raised for meat purposes such as veal calves. Since February 2020, a new Canadian federal regulation has forbidden calves <9 d old to be sold through auction markets. However, in the absence of a real-time birth registry...

The sensitivity (Se) and specificity (Sp) of three diagnostic tests for the detection of Campylobacter fetus venerealis (Cfv) using field samples were estimated using a Bayesian latent class model (BLCM), accounting for the absence of a gold standard. The tests included in this study were direct immunofluorescence antibody test (IFAT), polymerase c...

The objective of this study was to describe the proportion of enteric and respiratory pathogens and diseases in unvaccinated pre-weaned dairy heifers, in their first 2 weeks of life (exam 1), and at 4- to 8-weeks old (exam 2). Heifers from 20 dairy herds were examined and sampled twice for respiratory and enteric pathogens and diseases. Respiratory...

Clinical scores are commonly used for cattle. They generally contain a mix of categorical and numerical variables that need to be assessed by scorers, such as farmers, animal caretakers, scientists, and veterinarians. This article examines the key concepts that need to be accounted for when developing the test for optimal outcomes. First, the targe...

The objective of this observational cross-sectional study was to describe the cleanliness of various equipment used for colostrum harvest and calf feeding procedures on dairy farms in Québec, Canada. The study was performed on 42 commercial dairy herds also enrolled in another study aiming to determine the transfer of passive immunity over a 14-mo...

The objectives of this retrospective analysis were to: 1) estimate the diagnostic sensitivity (Se) and specificity (Sp) of bacterial culture of environmental samples for determining Mycobacterium avium subsp. paratuberculosis (MAP) infection status in Québec dairies, using a Bayesian Latent Class Model (BLCM); and 2) determine the association betwe...

The objective of this study was to quantify the reproductive performance of 4 reinsemination strategies in cows diagnosed nonpregnant using corpus luteum color flow Doppler ultrasonography on d 21 after last insemination. A total of 2,140 color flow Doppler ultrasonography exams from 845 Holstein cows from 10 commercial dairy herds were used in thi...

In dairy calves raised for veal, typical clinical signs of bovine respiratory disease (BRD) are ocular discharge, nasal discharge, ear droop or head tilt, abnormal respiration , cough, and increased rectal temperature. Despite the existence of several clinical scoring systems, there are few studies on the variability of human recognition of individ...

The main objective of this study was to quantify the effect of pegbovigrastim (PEG) as an adjunct therapy for naturally occurring severe mastitis cases on survival, intramammary bacteriological cure, and subsequent milk production. A double-blinded, randomized controlled trial was conducted on a single commercial dairy farm. During the study period...

The sensitivity (Se) and specificity (Sp) of three diagnostic tests for the detection of Campylobacter fetus venerealis (Cfv) using field samples were estimated using a Bayesian latent class model (BLCM), accounting for the absence of a gold standard. The tests were direct immunofluorescence antibody test (IFAT), polymerase chain reaction (PCR), an...

The bacterium Coxiella burnetii (C. burnetii) can infect a wide range of animals, most notably ruminants where it causes mainly asymptomatic infections and, when clinical, it is associated with reproductive disorders such as abortion. It is also the etiological agent of Q fever in humans, a zoonosis of increasingly important public health concern....

Although future production of dairy goats is influenced by kid-rearing practices, little is known regarding which practices maximize kid growth, welfare, and future production success. The objectives of this survey study were to (1) identify common rearing practices of Canadian commercial dairy goat farms and evaluate their associations with 6 farm...

Background The best test between thoracic ultrasonography (TUS) and thoracic radiography (TR) or the best combination of tests (series or parallel) to detect active infectious bronchopneumonia (BP) in hospitalized dairy calves remains unknown. Hypothesis/Objectives To estimate performances of TUS and TR to detect active BP in hospitalized dairy ca...

Bovine respiratory disease (BRD) is one of the most common calfhood diseases in dairy cattle. Unfortunately, published data on the short- and long-term effects of calfhood BRD on health and performance are scarce and, when available, often conflicting and uncertain. The objective of this study was therefore to review the scientific literature on th...

Bovine respiratory disease complex (BRD) is a worldwide multifactorial infectious disease. Antimicrobials are commonly used for treating BRD because bacteria are often involved. The clinical diagnosis of BRD is a challenge, especially in adult dairy cows, where information on this syndrome is scant. Having a definition based on consistent and relia...

This study estimates the accuracy of the focused lung ultrasound (FLUS) compared with systematic thoracic ultrasonography (TUS) as the reference test for diagnosing pneumonia in pre- and postweaned dairy calves. One hundred thirty-five Holstein Friesian calves, aged between 1 to 6 mo were enrolled and were kept in the same pen with one or more anim...

Feeding high-quality colostrum is essential for calf health and future productivity. Therefore, accurate assessment of colostrum quality is a key component of dairy farm management plans. Direct and indirect methods are available for assessment of colostrum quality; however, the indirect methods are rapid, inexpensive , and can be performed under f...

The objective of this study was to identify the calf-level colostrum management practices associated with an adequate transfer of passive immunity (TPI; defined as serum Brix refractance ≥8.4% in the first week of life) in small-sized herds. A total of 818 calves from 61 commercial Holstein dairy farms were included in this observational cross-sect...

Dairy calves not kept for replacement are sold at young age in Québec auction markets for white and grain-fed veal calf production. The province of Québec produces 80% of the Canadian veal meat, but little information is available on the factors associated with the calves' price per crude weight (Can$/kg; Can$1 = US$0.78 at time of writing). The ch...

Inadequate transfer of passive immunity (TPI) is associated with increased risk for calfhood disease and increased risk of mortality and morbidity. Accurately diagnosing calves and herds with inadequate TPI is of primary importance and brix (BRIX) or classical refractometer (REF) devices are more practical for this purpose than measuring the serum...

The objective of this study was to identify herd-level colostrum management factors associated with the adequate transfer of passive immunity (TPI; defined as serum Brix refractance ≥8.4% in the first week of life). A total of 59 commercial Holstein dairy farms were included in this observational cross-sectional study. In every participating herd,...

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...

The objective of this study was to validate the diagnostic accuracy of the Petrifilm culture system (3M, St. Paul, MN) for identifying colostrum with excessive bacterial contamination. An observational cross-sectional study was conducted between October 2015 and February 2016. Two colostrum aliquots were collected during the first meal of 332 calve...

Le Québec produit 80% des veaux lourds au Canada. Les élevages de veaux lourds présentent: un taux de mortalité de 8-10% et un taux de morbidité jusqu'à 60%. L'objectif de l'étude était l'évaluation des caractéristiques et de la santé des veaux vendus lors de la vente aux encans. Deux visites aux encans de Saint-Hyacinthe et de Saint Isidore ont ét...

Infectious bronchopneumonia is a lower respiratory tract disease with major economic consequences in dairy calves. Thoracic radiography (TR) and thoracic ultrasonography (TUS) are two imaging diagnostic procedures available in bovine medicine for identifying thoracic lesions. However, no study has investigated whether one of these tests is superior...

Background: Use of different analyzers to measure electrolytes in the same horse can lead to different interpretation of acid-base balance when using the simplified strong ion difference (sSID) approach. Objective: Investigate the level of agreement between 2 analyzers in determining electrolytes concentrations, sSID variables, and acid-base dis...

Bovine respiratory disease (BRD) complex is a worldwide health problem in cattle and is a major reason for antimicrobial use in young cattle. Several challenges may explain why it is difficult to make progress in the management of this disease. This article defines the limitation of BRD complex nomenclature, which may not easily distinguish upper v...

When it is desired to identify infectious agents involved in an outbreak of bovine respiratory disease, a variety of possible sampling methods may be used. For field use, the deep nasopharyngeal swab, transtracheal wash, and nonendoscopic bronchoalveolar lavage are most feasible. At present, bacterial culture and polymerase chain reaction testing a...

Background Data on the performance of a glucometer in calves with different diseases are currently lacking. Objective The primary objective of this study was to evaluate the reliability of a point of care glucometer in calves affected by different diseases relative to a traditional bench‐top autoanalyzer. Animals One hundred ninety‐six calves wit...

Background: Spinal cord dysfunction/compression and ataxia are common in horses. Presumptive diagnosis is most commonly based on neurological examination and cervical radiography, but the interest into the diagnostic value of transcranial magnetic stimulation (TMS) with recording of magnetic motor evoked potentials has increased. The problem for t...

Digital dermatitis (DD) is a worldwide infectious disease of cattle that causes lameness, discomfort, and economic losses. The reference standard test to diagnose DD is visual observation in a trimming chute, which cannot be practically performed daily on dairy farms. Moreover, some lesion misclassification may occur using this standard diagnostic...

Infection of the oviduct by an infectious bronchitis virus (IBV) in laying hens has been associated with the false layer syndrome. Because the diagnostic procedure for the detection of cystic oviducts by postmortem examinations in IBV-positive replacement pullet flocks could involve the unnecessary sacrifice of numerous healthy pullets without repr...

Kid rearing is the foundation of goat milk production, yet little is known about how to raise replacement does efficiently to make healthy and productive dairy animals. This study aimed to identify the common rearing practices of Canadian commercial dairy goat farms (≥40 goats/farm), from birth to weaning, and to determine best management practices...

Dairy calves are at risk of being stressed when transported during the first week of life. A new Canadian federal rule will forbid transportation of calves younger than 9 d old to auction market. However, in the absence of reliable information to determine birth date, other indirect methods would be of interest. This study aimed to determine the pr...

Paratuberculosis is a worldwide infectious disease caused by Mycobacterium avium ssp. paratuberculosis (MAP). Various ruminant species can be affected by the disease, and the diagnosis of the disease is challenging in the absence of a gold standard test. The aim of this systematic review protocol is to determine the accuracy of the direct and indir...

The main objective of this study was to determine the accuracy of corpus luteum color flow Doppler ultrasonography (CLCFDU) to diagnose nonpregnant dairy cows 21 d after insemination. A secondary objective was to determine the accuracy of other indirect tests such as corpus luteum size and progesteronemia. Data from 1,632 Holstein cows (10 commerci...

The use of a brix refractometer on dairy farms for colostrum management is becoming more common. This cow-side test can indirectly assess colostrum immunological quality and provide inputs to make decisions regarding colostrum feeding to calves. Achieving a high prevalence of transfer of passive immunity (TPI) success depends on factors such as col...

Severity of lung lesions quantified by thoracic ultrasonography (TUS) at time of bronchopneumonia (BP) diagnosis predicted death among feedlot steers non-treated for this condition. Further research is now needed to confirm that lung lesions detected by TUS can be associated with negative outcomes in cattle with BP that were subsequently treated fo...

The detection of lung lesions in dairy calves is commonly achieved using thoracic ultrasonography (TUS) and radiography (TR). However, it remains unclear from the literature if one diagnostic procedure is superior to another. The main objective of this study was therefore to evaluate the sensitivity (Se) and specificity (Sp) of TUS and TR to detect...

This study aimed to explore the dynamics of lung consolidation in preweaned calves and the association between ultrasonographic findings and prognosis (defined as the time until first consolidation occurrence during the preweaning period) and average daily gain. Two dairy herds were visited weekly for 9 weeks. The preweaned dairy heifers were: exam...

This study aimed to explore the dynamics of lung consolidation in preweaned calves and the association between ultrasonographic findings and prognosis (defined as the time until first consolidation occurrence during the preweaning period) and average daily gain. Two dairy herds were visited weekly for 9 weeks. The preweaned dairy heifers were: exam...

In practice, veterinary surgeons frequently rely on lung auscultation as a confirmation test for pneumonia. To what extent diagnostic accuracy of lung auscultation varies between different practitioners is currently unknown. In this diagnostic test study, 49 Dutch veterinarians each auscultated between 8 and 10 calves, and communicated whether they...

Mycobacterium avium subspecies paratuberculosis (Map) is the etiological agent of paratuberculosis of domestic and wild ruminants. Map strains are segregated into 2 main groups or strain types referred to as sheep (S) type and cattle (C) type. Few small ruminant Map strains have been genetically characterized to date. The present study was undertak...

The veal calf industry in Québec depends on young calves' availability at auction. Most of these calves come from dairy farms. The aim of this cross-sectional study was to determine the effect of clinical anomalies and other calf characteristics on their sale price. A total of 3,820 calves from 5 different auctions were included in this observation...

Background: Severity of lung lesions quantified by thoracic ultrasonography (TUS) at time of bronchopneumonia (BP) diagnosis predicted death among feedlot steers non-treated for this condition. Further research is now needed to confirm that lung lesions detected by TUS can be associated with negative outcomes in cattle with BP that were subsequentl...

Fig S3 Distribution of maximal area of lung consolidation in feedlot cattle diagnosed with BP (n = 144).

Table S2 Effects of maximal depth and maximal area of lung consolidation at first BP diagnosis on risk of BP relapse. Only cattle for which both thoracic sides were examined by TUS were included (n = 101).

Fig S1 Flow diagram of cattle enrolled in the study.

Fig S2 Distribution of maximal depth of lung consolidation in feedlot cattle diagnosed with BP (n = 144).

Table S1 Descriptive statistics of health and performance of the feedlot cattle (n = 144) enrolled in the study

Table S3 Effects of maximal depth and maximal area of lung consolidation at first BP diagnosis on average daily gain calculated from 1 to 120 days on feed. Only cattle for which both thoracic sides were examined by TUS were included (n = 101).

Hypotheses and Objectives Hypotheses 1. The prevalence of respiratory pathogens is lower in young calves housed in individual boxes in comparison with older calves housed and fed in groups; 2. The prevalence of respiratory bacterial pathogens antimicrobial resistance is higher in group raised calves; 3. Prevalence of Cryptosporidium parvum and rota...

Among the different clinical presentations of bovine respiratory disease, active pneumonia, defined as an infection of the lower airway with signs of inflammation, is the most important to diagnose correctly so appropriate treatment can be initiated. Diagnostic tests that accurately identify cases of active pneumonia are lacking; however, thoracic...

Objective: Evidence-based medicine (EBM) is used in various areas including veterinary medicine. The assessment of the quality of systematic review and meta-analyses (SR-MA) despite their importance in the EBM process is uncommonly performed in veterinary medicine due to the absence of specific dedicated tools. The main objective of this observatio...

A 3-week-old female dairy calf was presented because of severe weakness and diarrhea. Physical examination and ultrasound findings lead to a tentative diagnosis of intestinal obstruction, although serum biochemistry suggested a primary renal disorder. Reassessment of ultrasound images allowed diagnosis of hydronephrosis that had been misdiagnosed p...

Ceftiofur is a class 1 antibiotic (World Health Organization classification) and there is an increasing pressure from the veterinary and medical bodies to revisit its use for treating and preventing diseases in dairy cows such as acute puerperal metritis (APM). The presence of Escherichia coli (E. coli) in the uterus of dairy cows at day 1 postpart...

Ultrasonography is a diagnostic test that is widely used in cattle practice for reproductive tract assessment. Other indications of medical ultrasonography are numerous in cattle. Ultrasound use can easily be extended as part of the evaluation of different medical and surgical conditions in beef cattle practice. The aim of this article is to focus...

A latent class model fit within a Bayesian framework was used to estimate the sensitivity and specificity of individual fecal culture (IFC) in liquid medium (Para TB culture liquid medium and BACTEC MGIT 960 system) for the detection of Mycobacterium avium subsp. paratuberculosis (MAP) infections in Québec dairy cows. As a secondary objective, the...

Background Thoracic ultrasonography (TUS) can be used to assess the extent and severity of lung lesions associated with bronchopneumonia (BP) in feedlot cattle. Hypothesis/Objectives To assess inter‐rater agreement and reliability of TUS findings in feedlot cattle, with or without naturally occurring BP. Animals Feedlot steers with (n = 210) or w...

Bovine respiratory disease complex is a major cause of illness in dairy calves. The diagnosis of active infection of the lower respiratory tract is challenging on daily basis in the absence of accurate clinical signs. Clinical scoring systems such as the Californian scoring system, are appealing but were developed without considering the imperfecti...

The objective of this study was to quantify the prevalence of hypoglycemia in hyperketonemic dairy cows during the early postpartum period. A prospective observational study was conducted in 100 dairy herds selected by convenience. Within all participating herds, 40 cows (or the entire herd if smaller than 40 cows) were enrolled in the study (total...

Paratuberculosis is a chronic and contagious enteric disease of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). Control of paratuberculosis is justified given the associated economic losses and the potential role of MAP in Crohn’s disease in humans. Management practices that limit exposure of susceptible animals to MAP are mo...

Figure S1. Forest plot and summary receiver operating characteristic plot of studies reporting the accuracy of refractometry and Brix refractometry in the same calves for the diagnosis of inadequate transfer of passive immunity in calves. Figure S2. Forest plot and hierarchical receiver operating characteristic (HSROC) curve of studies reporting t...

Supporting Information File 1 – Guidelines_for_ultrasound_raters

Supporting Information File 2 – Open_Access_Data_Set

Background: Transfer of passive immunity in calves can be assessed by direct measurement of immunoglobulin G (IgG) by methods such as radial immunodiffusion (RID) or turbidimetric immunoassay (TIA). IgG can also be measured indirectly by methods such as serum refractometry (REF) or Brix refractometry (BRIX). Objectives: To determine the accuracy...