Usefulness of differential somatic cell count for udder health monitoring: effect of intramammary infections, days in milk, quarter location, and parity on quarter-level differential somatic cell count and somatic cell score in apparently healthy dairy cows.

Microbial infections of the mammary gland often cause mastitis, and it can lead to substantial economic losses within the dairy industry due to its direct negative impact on milk production and composition and the associated treatment costs. Somatic cell count has emerged as a critical indicator in monitoring udder health, and recently, the large-scale availability of differential cell count analysis potentially offers new insights into underlying physiological processes. Therefore, the main objective of this study was to estimate the variation of DSCC and SCC of individual quarter-level milk samples of cows according to 1) their intramammary infectious status; 2) parity of the cow; 3) quarter location; and 4) DIM at the time of sampling.

Usefulness of differential somatic cell count for udder health monitoring: Identifying referential values for differential somatic cell count in healthy quarters and quarters with subclinical mastitis.

Mastitis, an inflammation of the udder primarily caused by an intramammary infection, is one of the most common diseases in dairy cattle. Somatic cell count (SCC) has been widely used as an indicator of udder inflammation, assisting in the detection of subclinical mastitis. More recently, differential somatic cell count (DSCC), which represents the combined proportion of lymphocytes and polymorphonuclear leukocytes, has become available for routine dairy milk screening, though it was not yet widely studied.

Usefulness of differential somatic cell count for udder health monitoring: Diagnostic performance of somatic cell count, and differential somatic cell count for diagnosing of intramammary infections in dairy herds with automated milking systems.

Mastitis poses significant economic challenges for dairy farms. Therefore, enhancing the accuracy of diagnostic methods for detecting intramammary infections (IMI) can potentially improve prevention, control and treatment strategies. The somatic cell count (SCC) is a well-established parameter for identifying inflammation resulting from IMI.

Quantifying the impact of frequent diseases and syndromes on calf health using the opinions of producers and veterinarians: Towards dairy calf disability weights.

The first objective of this study was to quantify the impact and disability weight (DW) of frequent diseases or syndromes of pre-weaned dairy calves using the perceptions of producers and veterinarians. The second objective was to compare the opinions of producers and veterinarians regarding the impact and DW of dairy calves' frequent diseases and syndromes. A survey was conducted to obtain demographic information and opinions of 39 dairy producers and 52 veterinarians on the impact of frequent disease and syndromes on calf health.

Association between adenosine triphosphate luminometry of feeding equipment and environmental and health parameters of preweaning calves on dairy farms.

The objective of this study was to examine the influence of different environmental factors on ATP luminometry measurements of feeding equipment and to investigate associations with health of preweaning calves and the levels of ATP identified through luminometry. On 50 commercial dairy farms in Quebec, Canada, ATP luminometry measurements (in relative light units, RLU) were obtained using the direct swabbing technique with Hygiena UltraSnap swabs and a liquid rinsing technique with the same swab for automatic milk feeders (AMF), bottles, buckets, esophageal tube feeders (ET), milk replacer, nipples, and water. During this visit, environmental factors (including temperature, air draft, humidity, ammonia, and bacterial count) were collected, and a clinical examination (including respiratory score and fecal score) was performed for all preweaning calves present at the farm.

Hygiene management practices and adenosine triphosphate luminometry of feeding equipment in preweaning calves on dairy farms in Quebec, Canada.

The objective of this study was to describe the cleaning practices currently used for preweaning calves on dairy farms in Quebec, Canada. In addition, contamination of feeding equipment for preweaning calves was described using ATP (expressed as relative light units, RLU), visual assessment, and bacteriological analysis. A questionnaire was administered on 50 commercial dairy farms in Quebec, Canada, regarding the self-reported cleaning protocol used for feeding equipment of preweaning calves.

Standardization and validation of ATP luminometry as a diagnostic tool to assess the cleanliness of feeding equipment in preweaning calves.

The objective of this cross-sectional study was to standardize a reliable and repeatable swabbing technique using ATP luminometry (light emission proportional to the amount of ATP with result provided in relative light units [RLU]) to describe the cleanliness of various feeding equipment used for preweaning calves in dairy farms. A total of 7 Québec commercial dairy herds were selected conveniently. Following visual hygiene scoring, the cleanliness of every available piece of feeding equipment was assessed using direct surface swabbing for buckets and nipples with Hygiena UltraSnap swabs.

Reproductive performance of lactating dairy cows with elevated milk β-hydroxybutyrate levels during first 6 weeks of lactation.

Although there is evidence that ketosis negatively affects fertility, the effect of late and early ketosis on the reproductive performance of lactating cows has not been systematically investigated. The aim of this study was to evaluate the association between time and amplitude of elevated milk BHB (EMB) occurring within 42 d in milk (DIM) and subsequent reproductive performance of lactating Holstein cows. The dairy herd information data of 30,413 cows with 2 test-day milk BHB recordings during early lactation periods 1 and 2 (5-14 and 15-42 DIM, respectively) assessed as negative (<0.

Toward Precision Feeding Regarding Minerals: What Is the Current Practice in Commercial Dairy Herds in Québec, Canada?

This analysis is performed to obtain information on the current situation regarding phosphorus (P), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn) concentrations in cow diets of commercial dairy herds in Québec, Canada, and to compare them with National Research Council recommendations. Data are collected on 100 Holstein dairy herds in Québec, Canada, and 4430 cows were involved. Rations are analyzed for selected minerals and cow requirements relative to the recommendations were calculated.

Fatty Acid Profiles from Routine Milk Recording as a Decision Tool for Body Weight Change of Dairy Cows after Calving.

Cows mobilize body reserves during early lactation, which is reflected in the milk fatty acid (FA) profile. Milk FA can be routinely predicted by Fourier-transform infrared (FTIR) spectroscopy, and be, thus, used to develop an early indicator for bodyweight change (BWC) in early lactating cows in commercial dairy farms. Cow records from 165 herds in Denmark between 2015 and 2017 were used with bodyweight (BW) records at each milking from floor scales in automatic milking systems.

Evaluation of the new differential somatic cell count parameter as a rapid and inexpensive supplementary tool for udder health management through regular milk recording.

Mastitis, particularly in its subclinical form, is the costliest disease in milk production causing substantial financial losses to the dairy industry, impairing animal welfare, and one of the main reasons for treating dairy cows with antimicrobials. Somatic cell count (SCC) is broadly used as an indicator for mastitis or intramammary infection (IMI) and is the basis for udder health management programmes, e.g.

Milk β-hydroxybutyrate concentration measured by Fourier-transform infrared and flow-injection analyses from samples taken at different times relative to milking.

Analysis of milk BHB concentration by Fourier-transform infrared (FTIR) spectrometry more frequently than regular milk testing could help dairy producers in decision making, particularly if it would be possible to use small hand-stripped samples (hereinafter simply called samples) taken between dairy herd improvement (DHI) test-samples analysed using DHI algorithms. The aim of this Research Communication was to evaluate milk BHB concentration and the prevalence of elevated milk BHB concentration analysed by FTIR spectrometry compared with flow-injection analysis (SKALAR) from samples taken at different times relative to the milking. A total of 293 early-lactation cows in 44 commercial dairy herds were involved in the study.

Calculations of apparent ruminal synthesis and intestinal absorption of biotin in dairy cows as influenced by the extraction method.

Biotin is present in nature either free or as biocytin, which is only degraded under the action of a specific enzyme: biotinidase. This enzyme is not included in analytical assays generally used. A method for sample preparation using biotinidase was developed in our laboratory before analysis by ELISA.