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How Do Domestic Herbivores Select Nutritious Diets on Rangelands?
No full text8 pp.Animal learning has been shown to play a major role in the development of diet selection by domestic herbivores. Dr. Frederick Provenza and his associates at Utah State University have conducted a series of experiments over the past 15 years to learn how physiological and behavioral mechanisms govern diet selection. This publication synthesizes several key diet selection concepts presented in four recent articles
How Do Domestic Herbivores Select Nutritious Diets on Rangelands?
No full textAnimal learning has been shown to play a major role in the development of diet selection by domestic herbivores. Dr. Frederick Provenza and his associates at Utah State University have conducted a series of experiments over the past 15 years to learn how physiological and behavioral mechanisms govern diet selection. In this paper, we synthesize several key diet selection concepts presented in 4 recent articles (i.e., Provenza et al. 1992; Provenza 1995, 1996, 1997)
How Do Animals Learn if Rangeland Plants are Toxic or Nutritious?
No full textOver the past 15 years, Dr. Frederick Provenza and his associates at Utah State University have studied how animals use certain physiological and behavioral processes to learn whether rangeland forages are toxic or nutritious. This article summarizes key concepts presented in recent articles (e.g., Provenza et al. 1992; Provenza 1995, 1996, 1997) about how learning plays a major role in the development of dietary choices made by rangeland animals
Recommended from our members
How Do Domestic Herbivores Select Nutritious Diets on Rangelands?
No full text8 pp. / Originally published: 1998Animal learning has been shown to play a major role in the development of diet selection by domestic herbivores. Dr. Frederick Provenza and his associates at Utah State University have conducted a series of studies over the past 30 years to learn how physiological and behavioral mechanisms govern diet selection. In this paper, we synthesize several key diet selection concepts presented in 4 articles (i.e., Provenza et al. 1992; Provenza 1995, 1996, 1997). Reviewed 12/2014; originally published 05/1998
Experience Influences Diet Mixing by Herbivores: Implications for Plant Biochemical Diversity
No full textWe often assume the intrinsic value of a food or habitat is similar for individuals of a species and above a certain threshold density more profitable foods should always be preferred over less profitable foods. Nevertheless, individual herbivores differ in their preferences for foods due in part to experience, and experience in variable environments is variable. In this report, we show that how sheep learned about their foraging environment was crucial to the development of their dietary habits, and that experience with foods that contained plant secondary metabolites (PSM) markedly enhanced their use of PSM-containing foods, even when familiar, nutritious alternatives were available ad libitum. Lambs who learned to eat foods that contained either tannins, terpenes, or oxalates ate more when they could select two of the foods offered simultaneously (tannins-terpenes, tannins-oxalates, or terpenes-oxalates) than when they were offered only one food. Lambs offered foods containing all three toxins ate more than lambs offered two of the toxins, and their intake was comparable to lambs offered the food that contained no toxins. Experience and the availability of nutritious alternatives both influenced food choice when the preferences of lambs with 3 months’ experience mixing tannin, terpenes, and oxalates were compared with lambs naive to the toxin-containing foods. During these studies, all lambs were offered five foods, two of them familiar to all of the lambs (ground alfalfa and a 50:50 mix of ground alfalfa:ground barley) and three of them familiar only to experienced lambs (a ground ration containing either tannins, terpenes, or oxalates). Half of the lambs were offered the familiar foods ad libitum, while half of the lambs were offered only 200 g of each familiar food daily. Throughout the study, naive lambs ate much less of the foods with toxins if they had ad libitum as opposed to restricted access to the nutritious alternatives (66 vs 549 g d−1). Experienced lambs also ate less of the foods with toxins if they had ad libitum, as opposed to restricted, access to the nutritious alternatives (809 vs 1497 g d−1). In both cases, however, lambs with experience ate remarkably more than naive lambs of the foods containing the toxins, whether access to the alfalfa-barley alternatives was ad libitum (811 vs 71 g d−1) or restricted (1509 vs 607 g d−1). These differences in food preferences and intake persisted during trials 8 months later. Plant communities offer a diverse matrix of biochemicals to herbivores, which may produce an array of interactions not accounted for by the traditional approach of studying nutrients and plant secondary metabolites (PSM) in isolation. How herbivores experience nutrient-PSM interactions may influence defoliation patterns and the potential for plant survival within plant communities. Thus, learning to mix foods that differ in kinds and concentrations of nutrients and PSM can enhance diet breadth and promote more uniform use of all plants in a community, which can influence the structure and function of ecosystems. Conversely, lack of experience learning to eat a variety of foods can diminish diet breadth and result in less uniform use of plants in a community. Herbivores are important agents of change in ecosystems and their influences vary across time and space (Hobbs 1996). Thus, ecologists have long been interested in developing rules to account for foraging behavior, but the generality of the proposed rules is lacking. According to optimal foraging theory, a consumer should either eat or ignore a food depending on the density of other more profitable foods – the “zero-one-rule” (Stephens and Krebs 1986), or the “none-or-all” rule (McNamara and Houston 1987). Nevertheless, herbivores typically exhibit partial preferences, such that a food is sometimes ingested and sometimes ignored (Kennedy and Gray 1993, Wilmshurst et al. 1995). Partial preferences have been explained in various ways, including limited perception (Berec and Krivan 2000), inability to discriminate among different plant species (Illius et al. 1999), and attempts to meet nutritional needs (Westoby 1978) and reduce intake of plant secondary metabolites (PSM) (Freeland and Janzen 1974). Most of these conclusions are based on the assumption that a single nutrient is sufficient to measure foraging success, with little consideration for the biochemical context where a plant is growing (Atsatt and O\u27Dowd 1976, Milchunas and Noy-Meir 2002). Nutrients and PSM do not act in isolation (Villalba et al. 2002a). Plant secondary metabolites impose nutritional costs to herbivores and nutrient intake affects detoxification processes (Illius and Jessop 1995). Nutrient-nutrient interactions influence growth and reproduction efficiencies in animals (Westoby 1978), while PSM–PSM interactions may influence the total amount of food an herbivore can ingest. Animals may be able to eat more foods with different kinds of PSM if they produce different effects in the body and they are detoxified by different mechanisms (Freeland and Janzen 1974). These interactions can lead to complementary relationships such that eating a combination of foods may exceed the benefit of consuming any one food in isolation (Tilman 1982). Emerging evidence suggests partial preferences occur as the body integrates the postingestive effects of nutrients and PSM with a food\u27s flavor, which result in flavor–nutrient–PSM interactions manifest as transitory preferences for a variety of foods (Provenza 1995, Provenza et al. 1998, 2002). In the process, individuals with different experiences may learn to eat different combinations of foods. Experience improves performance by inducing neurological, morphological, and physiological changes in animals (Provenza 1995, 1996, Provenza et al. 1998). Social and physical environments, continually interacting with the genome during growth and development, influence gene expression and generate new behavioral responses (McCormick et al. 2000, Dufty et al. 2002). Thus, while the body influences the structure of experience, experience also influences the structuring and functioning of the body (Provenza et al. 2003). These ongoing developmental processes enable individuals to adapt to local conditions and imply that what constitutes a “high quality” diet or habitat will differ for animals with different experiences. Sheep, goats and cattle reared on low-quality foods and habitats eat more low-quality foods and perform better than do animals that lack experience with those foods and habitats (Distel and Provenza 1991, Distel et al. 1994, 1996, Wiedemeier et al. 2002). Herein we show that sheep learn to mix diets as a function of: (1) their experiences eating a variety of foods that contain different kinds of PSM and (2) of the availability of nutritious alternatives that do not contain PSM. We show that how sheep learn about their foraging environment is crucial to the development of their dietary habits. Animals who learn to eat different combinations of foods exhibit greater dietary breadth than animals familiar with only a few foods. Thus, experience enhances diet breadth and may promote greater use of all plants, which can influence the structure and function of ecosystems
Frederick D. Rossini
No full textFREDERICK D. ROSSINI
NBS: 1928 -1950
Birth: July 18, 1899, Monongahela, Pennsylvania
Death: October 12, 1990, Juno Beach, Florida
EDUCATION:
Carnegie Institute of Technology: BS (Chemical Engineering), 1926; MS (Physical Chemistry), 1926; ScD (honorary), 1948
University of California, Berkeley, PhD (Physical Chemistry), 1928
PRINCIPAL FIELDS:
Thermodynamics; thermochemistry; physical chemistry of hydrocarbons
POSITIONS HELD AT NBS:
Chief, Thermochemistry Section
HONORS:
U.S. Department of Commerce Gold Medal, 1950
Chemical Society of Washington Hillebrand Award, 1934
American Chemical Society: William H. Nichols Medal, 1966; Priestley Medal, 1971
National Medal of Science, 1977
Elected to Sigma Xi
MEMBERSHIPS:
American Association for the Advancement of Science (Fellow)
American Institute of Chemists (Fellow)
American Physical Society (Fellow)
American Institute of Chemical Engineers
American Petroleum Institute
American Society for Engineering Education
American Society for Testing Materials
National Academy of Sciences
Philosophical Society of Washington
Washington Academy of Sciences (Editor of journal; Secretary; President)
Cosmos Club
PUBLICATIONS:
Author or co author of 265 scientific publications, including eleven books. Co author of The Thermochemistry of the Chemical Substances, Reinhold, 1936, which received world wide recognition. This book was revised and expanded as Selected Values of Chemical
Thermodynamics Properties, published as NBS Circular 500 in 1952, which has been called "the Bible of chemical thermodynamics.
Donald Frederick Haynes Family
No full textDonald Frederick Haynes stands with his wife Lilah Mae (Baer) and daughter Dona Louise. Pastor D. F. Haynes sang in a quartet at the 1946 General Conference Session praise service on the morning of June 14. Donald was the son of evangelist and author Carlyle Boynton Haynes.https://scholarsrepository.llu.edu/general-conference-1946-gallery/1011/thumbnail.jp
The Wars of Frederick The Great
No full textThe online publication is available at http://scientiamilitaria.journals.ac.za/pubThe study of the wars of Frederick the Great by Dennis E. Showalter is both fascinating and informative. King Frederick II ruled Prussia from 1740 to 1786. During his reign Prussia was involved in a number of wars (notably the Seven Years War). The reign of Frederick is acknowledged as the era in which Prussia was establish as a first ranking power in Europe. Yet, the Wars of Frederick the Great is more than just a campaign history of Frederick's wars. In this study the author places Frederick's wars, Frederick's reign in Prussia and the art of war and statecraft within the context of the time, which makes this work an important contribution to the study of Military History and power politics in the eighteenth century.Publisher's versio
THE WARS OF FREDERICK THE GREAT
No full textThe study of the wars of Frederick the Great by Dennis E. Showalter is both fascinating and informative. King Frederick II ruled Prussia from 1740 to 1786. During his reign Prussia was involved in a number of wars (notably the Seven Years War). The reign of Frederick is acknowledged as the era in which Prussia was establish as a first ranking power in Europe. Yet, the Wars of Frederick the Great is more than just a campaign history of Frederick's wars. In this study the author places Frederick's wars, Frederick's reign in Prussia and the art of war and statecraft within the context of the time, which makes this work an important contribution to the study of Military History and power politics in the eighteenth century.</p
Origins of Food Preference in Herbivores
No full textFood preference is best understood as the interaction between taste and postingestive feedback, determined by an animal\u27s physiological condition and to a food\u27s chemical characteristics. Taste (as well as smell and sight) enables animals to discriminate among foods and provides hedonic sensations associated with eating. Postingestive feedback calibrates taste in accord with a food\u27s homeostatic utility: preference increases when foods are adequate in nutrients; conversely, preference decreases when foods are deficient in nutrients, when they contain excesses of toxins, and when they are too high in rapidly digestible nutrients. Preference also decreases when familiar foods are eaten too frequently or in excess, which causes animals to eat varied diets. Experiences early in life affect preference. Young animals acquire dietary habits as a result of eating particular foods, and they are reluctant to eat novel foods or familiar foods whose flavors have changed. These findings suggest: (1) deterrents based merely on offensive flavors are not likely to be effective in the absence of aversive postingestive effects, (2) many repellents are ineffective because they merely change the flavors of familiar foods (i.e., novelty effects), and (3) management to deter herbivores from eating foods must provide nutritious alternatives
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