Considerable work has been done on both wild and domestic ruminant feeding behaviors and digestive physiology.
For example, see http://www.deer.rr.ualberta.ca/library/guild/Berlin.html This citation has a rather good literature list on the topics being discussed. My friend Prof. R. R. Hofmann of Berlin has devoted much of his career to work on this topic, so you might look for some of the following publications: Hofmann, R.R., Stewart, D.R.M.: "Grazer or browser: a classification based on the stomach-structure and feeding habits of East African ruminants. " Mammalia 36, (1972) : 226-240 Hofmann, R.R.: The ruminant stomach (stomach structure and feeding habits of East African game ruminants). East Afric. Monogr. Biol. Vol. 2 Nairobi: Kenya Literature Bureau, 1973 Hofmann, R.R., Geiger, G., König, R.: "Vergleichend-anatomische Untersuchungen an der Vormagenschleimhaut von Rehwild und Rotwild. " Z. Säugetierkunde 41, (1976) : 167-193 Hofmann, R.R., Schnorr, B.: Die funktionelle Morphologie des Wiederkäuer-Magens. Stuttgart: Enke, 1982, ISBN 3-432-88081-2 Hofmann, R.R.: "Digestive Physiology of the Deer - Their Morphophysiological Specialisation and Adaptation. " In: Drew, K., Fennessy, P. (eds.): Biology of Deer Production. Wellington, New Zealand: Royal Society of New Zealand, Bulletin 22, 1985 : 393-407 Hofmann, R.R.: "Morphophysiological evolutionary adaptations of the ruminant digestive system. " In: Dobson, A., Dobson, M.J. (eds.): Aspects of digestive physiology in ruminants. Ithaca, New York: Cornell University Press, 1988 : 1-20 Hofmann, R.R.: "Evolutionary steps of ecophysiological adaptation and diversification of ruminants: A comparative view of their digestive system. " Oecologia 78, (1989) :443-457 Hofmann, R.R.: "Die morphologische Anpassung des Verdauungsapperates des Rehs, seine evolutionäre Differenzierung und jahreszeitlichen Veränderungen. " In: Hofmann, R.R., Pielowski, Z. (eds.), Deutsch-Polnisches Rehwild-Symposium. 21, Melsungen: Neumann-Neudamm, 1993 : 15-22 Warren Aney Senior Wildlife Ecologist -----Original Message----- From: Ecological Society of America: grants, jobs, news [mailto:[EMAIL PROTECTED] On Behalf Of Alexandre Souza Sent: Wednesday, 12 April, 2006 04:56 To: [email protected] Subject: Digest on cattle feeding behaviour Dear friends, I am posting a digest on the following question I asked to the list a few days ago. Thank you very much to all who read and answered it. Alexandre ORIGINAL QUESTION Dear friends, I am preparing an article about the effects of cattle grazing on the structure of subtropical riparian forests, and I want to depart from the ecological foundations of the issue: what kind of predators are cows and what kind of effects one could expect them to have on forest communities, based on ecological theory? Do anyone knows of key references on cattle foraging behaviour regarding forest seedlings and saplings? Are they specialists or generalists? Do they impact forest communities more by trampling or by grazing? I have found mainly descriptive articles on net effects on forest strucuture, but I am finding it somewhat hard to find the above-mentioned questions addressed in the ecological literature. Thanks in advance, All the best, Alexandre ANSWERS I HAVE RECEIVED * The Konza Prairie LTER in Manhattan, Kansas, USA has done a number of studies comparing foaging impacts of domestic cattle and buffalo. You might try to do a search for Konza and buffalo and see what you get; * A researcher at Texas Tech was modelling the grazing behavior of cattle back around 1994. I don't recall his name but he was in the department of range scienes and was applying the disc equation to cattle feeding. Back in my undergrad days I took some ag classes and recall that in comparing goats, sheep, cattle, and bison that bison tended to clip grasses and preferred the fresh grass (in fact native americans would use fire to keep bison in their area). Cattle tend to prefer forbes, althought they do eat the grasses. Cattle will pick clean all the forbes out of a pasture over time. They also pull vegetation rather than clip it, leading to a different kind of grazing pressure on the vegetation. Sheep tend to pull as well, but also tend to leave much shorter grazing pastures. Sheep will feed on much "rougher" pasture than cattle and are better converters of rough forage. Goats tend to be browsers and will reportedly starve on a grass field if no forbes are present. B! y no means am I a ruminant biologist, but I think I recall this info accurately. I recommend you contact the folks at Texas Tech as they will probably have good info for you. If I remember the Prof's name I will email it to you, but its been so long! Another good source of information is to look into some animal science departments or textbooks. There are various papers and books on ruminant biology, forage management, pasture management, and range management that might provide you with the information that you are seeking. * Dear Alexandre, our group works on ruminant foraging behaviour in (sub)tropical environments. Check our website for articles and staff who might help you find the information you're looking for. Jasja Dekker, PhD student, Resource Ecology Group, Dept. Environmental Sciences, Wageningen University. Bornsesteeg 69 6708 PB Wageningen The Netherlands http://www.reg.wur.nl/UK/Staff/ * I am currently thinking a lot about classification of consumers in consumer-resource systems. I work with predator-prey models but have recently become interested in the larger issue of "what if any discrete categories of consumers are there?". Cows are tough... by one definition they are parasites (eat only part of their host), by another they are predators (larger than their host), by another they are parasitoids (generation time is about the same as their hosts [?Maybe?]). Cows are the best example of how little these categories actually mean. Dr. Alexandre F. Souza Programa de Pós-Graduação em Biologia: Diversidade e Manejo da Vida Silvestre Universidade do Vale do Rio dos Sinos Av. UNISINOS 950 - C.P. 275 São Leopoldo 93022-000 RS - Brasil Telefone: (051)3590-8477 ramal 1263 Skype: alexfadigas [EMAIL PROTECTED] http://www.unisinos.br/laboratorios/lecopop
