applied dairy microbiology, second edition - elmer h. marth

[...]... and digest the cellulose via cell-bound enzymes; this adherence appears to be a prerequisite to rapid cellulose digestion (Latham et al., 1978; Costerton et al., 1987; Kudo et al., 1987) The cell-associated cellulolytic enzymes are apparently organized into supramolecular complexes resembling the cellulosome, an organ- Microbiology of the Dairy Animal 21 Figure 7 Stereo-optic view of the adherence of... slow digestion, must be supplemented with more rapidly digested cereal grains to adequately balance energy and protein requirements for high-producing dairy animals (Van Soest, 1994) The products of cellulose hydrolysis are cellodextrins (short water-soluble -1 ,4-glucosides of two to eight glucose units) that are subject to fermentation by both cellulolytic and noncelluloytic species (Russell, 1985)... comprising 35–50% of dry weight Individual cellulose molecules are linear polymers of β1,4-linked D-glucose molecules These chainlike molecules are assembled via 20 Weimer Figure 6 Schematic cross-sectional view of the cell wall of two plant cell types Abbreviations: ML, middle lamella; PW, primary wall; SW, secondary wall; L, lumen, which in the living cell contains the cytoplasm but is replaced with... Johnson 345 12 Fermented By-Products David R Henning 385 13 Public Health Concerns Elliot T Ryser 397 14 Cleaning and Sanitizing in Milk Production and Processing Bruce R Cords, George R Dychdala, and Francis L Richter 547 15 Control of Microorganisms in Dairy Processing: Dairy Product Safety Systems Robert D Byrne and J Russell Bishop 587 16 Regulatory Control of Milk and Dairy Products William W Coleman... is instead produced by gluconeogenic pathways, primarily using propionate, a major product of the ruminal fermentation Lactose, a disaccharide of D-glucose and D-galactose linked by an -1 ,4glycosidic bond, is synthesized by a series of reactions using D-glucose as the starting substrate Approximately 60% of the glucose consumed in the mammary gland is used for lactose synthesis Lactose concentration... of dairy cow in use today Improvements in animal breeding and genetics have yielded substantially larger animals over the years (Fig 1) with corresponding increases in feed intake This factor, combined with a gradual shift to diets having higher energy contents (i.e., higher proportions of grain) has resulted in a progressive increase in average milk production per cow, which in well-bred and well-managed... 6- to 8-week period and then slowly decreases for the rest of the lactation Normally, the cow is bred again at 11–12 weeks after calving, and delivers her next calf some 40 weeks later Thus, the cow is pregnant for the bulk of her lactation B Organization of the Digestive Tract The rumen is the first of the four preintestinal digestive chambers in ruminant animals and is physically proximate to the second. .. Food Sciences, Utah State University, Logan, Utah Robert D Byrne National Milk Producers Federation, Arlington, Virginia Warren S Clark, Jr American Dairy Products Institute, Chicago, Illinois William W Coleman Dairy Consultant and former Director of the Dairy and Livestock Division of the Minnesota Department of Agriculture, St Paul, Minnesota Bruce R Cords Environment, Food Safety, and Public Health,... Autotrophic, methylotrophic Can also reduce inorganic nitro compounds (e.g., NO3Ϫ ) Microbiology of the Dairy Animal ϩ Clostridium sticklandii Detoxifies TAA Detoxifies oxalate Detoxifies mimosine a 15 AA, amino acids; Arg, arginine; Cd, cellodextrins (except where indicated, glucose also fermented); DHP, 2, 3- and 3,4-dihydroxypyridinediols; EtOH, ethanol; F, fructose; For, formate; G, glucose; G2, cellobiose;... microflora into most laboratory culture environments Second, many protozoa in a variety of habitats contain intracellular or surface-attached bacterial symbionts that engage in syntrophic interactions with their hosts (Fenchel et al., 1977; Vogels et al., 1980) Thus, even when ‘‘pure’’ cultures of protozoa (i.e., single protozoal species in the absence of free-living bacteria) are established and maintained, . 21 2-6 8 5-4 540 Eastern Hemisphere Distribution Marcel Dekker AG Hutgasse 4, Postfach 812, CH-4001 Basel, Switzerland tel: 4 1-6 1-2 6 1-8 482; fax: 4 1-6 1-2 6 1-8 896 World Wide Web http://www.dekker.com The publisher offers. microbiology. This sec- ond edition of Applied Dairy Microbiology reflects that evolution and provides the reader with the latest available information. There are now 18 chapters, rather than the 14 found. in the first edition. Nearly all chapters that appeared in both editions have been revised and updated. Chapter 1, ‘‘Microbiology of the Dairy Animal,’’ contains more informa- tion on Escherichia