Subventions et des contributions :

Subvention ou bourse octroyée s'appliquant à plus d'un exercice financier (2017-2018 à 2018-2019).

Cattle industry is one of the major Canadian agriculture sectors, which provides the animal proteins (milk andx000D
meat) to humans. Recently, the direct fed microbes have been considered as one of the powerful approaches tox000D
have long term effect to improve the animal productivity and health through enhancing microbial fermentation.x000D
Biomate, manufactured by AB Mauri North America (LaSalle, QC) is one of the commercial available livex000D
yeast products (Saccharomyces cerevisiae variety) that can improve fiber digestion and prevent the ruminalx000D
metabolic dysfunction, resulting cattle with greater productivity and better health. On farm, the Biomate isx000D
usually mixed with the feed and provided to the animals through the day to achieve the maximum effect of thex000D
product. Therefore, it is essential to maintain the high level of the viable cells in feed. Currently, the evaluationx000D
of the activity of this product in feed uses the culture dependent methods. To evaluate the viable cells of yeastx000D
in feed, the cultivation of the yeast is usually performed at AB Mauri's lab, which takes 3-4 days that is timex000D
consuming and labor costly. Also, this method has a large error margin due to the manual nature of countingx000D
colonies. In addition, the cultivability of yeast sometime is affected by the high content of minerals or otherx000D
components in feed, which results in an underestimation of viable yeast in the sample. Although the PCRx000D
method can be used to monitor the population of targeted organisms, it can't differentiate the proportion ofx000D
non-viable and viable cells, which could lead to over-estimation of the viable cells in the sample. In this study,x000D
we propose to identify and target "marker genes" for viable yeast cells using microbial genomics and molecularx000D
biological based approaches. We will identify the DNA markers by aligning ~120 existing yeast genomes andx000D
then develop a single or multiplex PCR assay. The assay will then be validated using the mixed feed samplesx000D
from AB Mauri, together with the comparison of the cultured based methods. The rapid and effectivex000D
DNA/RNA based method will provide a reliable assay to quantify and to monitor the alive yeast cells in feedx000D
for AB Mauri lab.