Nordihydroguaiaretic acid (NDGA) is a secondary plant metabolite with antimicrobial properties, and therefore may have potential as a rumen modifier. Two in vitro experiments were conducted to determine the usefulness of NDGA as a rumen modifier. Exp. 1 evaluated the effect of adding 0, 5, 10, 50, and 100 mg/mL NDGA on growth of pure and mixed cultures of rumen bacteria. Growth of all cultures ...

Grape seed proanthocyanidin (GSP) contains polyphenolic bioflavonoids ubiquitously found in the lignified portions of grape seeds from winery and distillery industries, as an antioxidant. To explore its potential a rumen modifier methanogenesis inhibition, 2 × 5 factorial experiment was conducted to determine effect GSP at 0, 15, 30, 60 120 mg/g substrate on fermentation two representative tota...

This paper discusses recent work by the authors which has investigated the nutritional regulation of glycogen concentration in skeletal muscle of sheep and cattle. Several experiments are summarised which show a clear relationship between the level of glycogen in muscle and the intake of metabolisable energy. This translates into strong seasonal effects on muscle glycogen in pasture fed cattle....

The aim of this study was to investigate the effects of various doses of essential oils (EO) of thyme (TEO) or cinnamon (CEO) on in vitro rumen degradation of protein of a commercial total mixed ratio (TMR) containing 16.4% crud protein (CP). Treatments were TMR without any of EOs (control); control plus 25 µL of TEO (TEO25); control plus 50 µL of TEO (TEO50); control plus 25 µL of CEO (CEO25) ...

It has been known for decades that microbial fermentation within the rumen is critical to postnatal rumen epithelial growth and maturation in ruminants, but the underlying mechanism is largely unknown. In this study, we determined the effect of rumen fluid, which should contain all products from rumen fermentation, on growth of rumen epithelial cells in vitro. Addition of 10% rumen fluid from c...