17-79 ABSTRACT Cumulative gas production from incubation of feedstuffs with rumen liquor or a fresh faecal suspension as inoculum in vitro together with crude nutrient composition can be used to predict organic matter digestibility and metabolizable energy content of ruminant feeds with high accuracy. In this study, prediction equations were derived for roughages using 110 samples with known in...

The high fibrolytic activity and large biomass of strictly-anaerobic bacteria that inhabit the rumen makes them primarily responsible for the degradation of the forage consumed by ruminants. Llamas feed mainly on low quality fibrous roughages that are digested by an active and diverse microflora. The products of this fermentation are volatile fatty acids and microbial biomass, which will be use...

The hypothesis that infrequent feeding of sheep supports a higher rate of wool growth than frequent (daily) feeding was examined using oats grain and three roughages of varying protein content. The wool growth of Merino ewes fed every third and sixth day was significantly greater than that of similar ewes fed every day, when averaged over the four diets. Increased wool production due to infrequ...

The Malthusian doctrine put forward in the middle of the 18th century, forecast that the population of the world would, in a relatively short period of time, find it increasingly difficult to feed itself. I think it is obvious that, sooner or later, the world’s population must reach saturation point when the tragedy envisaged by Malthus will be with us. However, there are many ways of deferring...

The two approaches often are complementary, as treatments which increase intake or digestibility may generate a need for additional nutrients to supply the needs of rumen bacteria as well as of the host animal. In these papers we have considered nitrogen (N) requirements of rumen bacteria and of the animal, in animals fed untreated and chemically-treated forages of low nutritive value. The reas...

Two experiments were conducted to evaluate modified wet distillers grains (DGS) as a supplement for roughages. Wet DGS was superior to a mixture of corn and wet DGS as a supplement with tub-ground grass hay for growing steer calves in a 112-d study. Performance of steers fed the grass hay supplemented with DGS or the mixture of corn and DGS was superior to calves fed corn silage. However when D...

Agriculture accounts for 92% of the freshwater footprint of humanity; almost one third relates to animal products. In a recent global study, Mekonnen and Hoekstra (2012) [31] show that animal products have a large water footprint (WF) relative to crop products. We use the outcomes of that study to show general trends in the WFs of poultry, pork and beef. We observe three main factors driving th...