WenZhu Yang

By WenZhu Yang

The method of batch culture has been widely applied to evaluate feed value and screen feed additives. The advantages of using this in vitro technique as compared to in vivo methods are many, including low cost, simplicity, requirement of small quantities of feed or additives and the ability to screen large numbers of samples under similar experimental conditions. However, the number of factors associated with the batch culture could alter fermentation outcomes. This chapter discusses the potential impact of series factors on in vitro fermentation and the considerations on improving application of batch culture in ruminant nutrition. The factors that are discussed include inoculum source, gas-recording methods, substrate particle size, substrate delivery method, ratio of rumen inoculum to buffer in mixture of media and addition of soluble carbohydrate in media. Some recent important results obtained using batch culture technique have been highlighted and discussed. Any particular batch system being accepted as the ‘standard’ procedure seems difficult. However, before any protocol can be adopted, sufficient data need to be developed to reduce the variation and improve the consistence of the measurements.

Part of the book: Fermentation Processes

By Wenzhu Yang and Yanling Li

Wheat grain is commonly used to produce ethanol in Canada and Europe. During ethanol production processing, starch in the grain is fermented almost completely, and the remaining protein, fibre, fat, minerals and vitamins increase approximately 3-fold in concentration compared to the original grain. By-product derived from the ethanol production is named distiller grain and primarily used in feeding livestock animals. Wheat-based distiller grain is high in energy, protein and fibre. These properties give wheat distiller grain unique feeding opportunities for various classes of livestock as both energy and protein supplements as well as fibre source. This chapter summarizes some recent research findings published in peer reviewed and extension chapter on the use of wheat distiller grain in ruminant diets. Substantial variation in chemical composition exists among the distiller grain samples, which are mainly influenced by inherent original grain and technology used in ethanol plant. Wheat distiller grain can be used to partly replace grain or forage portion at moderate levels to meet energy and fibre requirements of cattle. A manure management plan needs to be developed that considers the fact that inclusion of wheat distiller grain in the diet will dramatically increase the nitrogen and phosphorus content in manure.

Part of the book: Wheat Improvement, Management and Utilization

By Khalil Safaei and WenZhu Yang

Milk production and milk components are of prime economic importance for dairy farmers. Although milk production depends largely on numerous dietary nutrients, energy and protein are most critical. Feed grains containing starch such as corn, barley, wheat, and sorghum as a primary source of energy are commonly fed to beef and dairy cattle to improve meat or milk productions. Feed grain needs to be processed prior to feed cattle to increase accessibility of the endosperm by microbial population in the rumen and the host enzyme in the intestine. Grain processing is done by the application of various combinations of heat, moisture, time and mechanical actions. This article outlines the effect of grain processing method and degree of processing on rate and extent of grain digestion in the digestive tract of cattle, and consequently on lactation performance and cattle health. Methods of grinding, rolling and steam flaking are particularly discussed on their advantages and disadvantages. The optimal degree of processing can achieve a balance between maximizing the extent and controlling the rate of starch digestion in the rumen to maximize utilization and avoid digestive and metabolic disturbances. A recent developed precision processing technique has been highlighted and discussed as well.

Part of the book: Herbivores

By Wenzhu Yang and Yizhao Shen

With adverse growing and harvesting conditions as well as the fluctuation of grain pricing, there have increased supplies of feed wheat used as livestock feed. However, the majority of wheat has been used as feed for poultry and swine, and ruminant producers have been reluctant to use large quantities of wheat because feeding wheat increases the risk of rumen acidosis due to rapid wheat starch digestion in the rumen. To avoid this problem, animal producers often believe that they must limit the amount of wheat in the diet to 50% or less. This chapter summarizes some research findings published in peer reviewed and extension articles on the use of feed wheat in ruminant diets. Substantial variation in physical and chemical composition exists among wheat samples, which are mainly influenced by type of wheat, variety and environmental conditions. Feed values of wheat are largely influenced by its physical properties and nutrient content; however, grain processing as well as its interaction with the physical characteristics is a critical consideration to optimize wheat utilization in ruminant diets. Wheat grain can be fed to animals at higher than typically used in the current livestock industry if proper bunk management and processing are employed.

Part of the book: Global Wheat Production