In contrast to ruminants, horses chew their food only once – but with the same regu-lar, rhythmic movements as cows, who ruminate their food after eating, as demon-strated by researchers at the University of Zurich and the ETH Zurich. They assume that ruminants chew their food less intensively during initial eating to protect their teeth.
Herbivores digest their food much better if it has been strongly fragmented by intensive mastication. For ruminants such as cows, sheep, goats, deer, llamas or camels, eating and ruminating are two different processes: Some time after feeding, they regurgitate part of their food and chew it again with particularly even, rhythmic movements. In this way, they achieve the maximum degree of fragmenta-tion of their food.
Mastication halters record the movements of the mouth and automatically differentiate between eating and ruminating.
Researchers of the University of Zurich and the Swiss Federal Institute of Technology Zurich (ETH Zurich) are now investigating whether the chewing movements of the ruminants are similar to those of other ruminants and other herbivores. In their study with horses, cows and camels, they use special mastication halters, which can record the movements of the mouth and automatically differentiate between eating and ruminating.
Similar rhythmic chewing movements
In the case of cows and camels, the mastication rhythms differ clearly in a predictable manner. The movements during eating were much more irregular than those during rumination, and camels gener-ally have a lower chewing rate during ruminate than cows. The situation is different for horses: “Much to our surprise, the evaluation software determined that horses do not eat, but rather ruminate,” says Marie Dittmann, doctoral student at the University of Zurich and ETH Zurich. “Although horses are not ruminants, they fragment their food with the same rhythmic chewing movements as cows do during rumination.”
For Marcus Clauss, professor at the Clinic for Zoo Animals, Exotic Pets and Wildlife of the University of Zurich, the similarity in the chewing rhythm of such different animal groups is understandable: “Horses do not have a second chance to re-chew something that is hard to digest. For that reason, they have to masticate very thoroughly when eating. That obviously works best with rhythmic and even movements.”
Irregular chewing protects the teeth
That begs another question: Why do cows chew differently when eating? The researchers have an interesting theory: When grazing in the wild, herbivores also take in dust, dirt or earth, which addition-ally abrades the teeth while eating. Horses have to put up with this problem. Ruminants, on the other hand, can postpone thorough mastication after the initial eating process until later after the food has been cleaned of such contamination in the rumen. Less tooth abrasion therefore results during eating due to less intensive chewing. “The irregular ingestive mastication of cows could therefore have de-veloped in order to protect the teeth while eating,” Clauss says. Further studies are necessary to con-firm this assumption.
Dittmann Marie T., Kreuzer Michael, Runge Ullrich, Clauss Marcus: Ingestive mastication in horses resembles rumination but not ingestive mastication in cattle and camels. 17 May 2017, Journal of Experimental Zoology A. DOI: 10.1002/jez.2075
Prof. Dr. Marcus Clauss
Clinic for Zoo Animals, Exotic Pets and Wildlife
University of Zurich
Phone: +41 44 635 83 76
Melanie Nyfeler | Universität Zürich
Researchers discover natural product that could lead to new class of commercial herbicide
16.07.2018 | UCLA Samueli School of Engineering
Advance warning system via cell phone app: Avoiding extreme weather damage in agriculture
12.07.2018 | Leibniz-Zentrum für Agrarlandschaftsforschung (ZALF) e.V.
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Physics and Astronomy
16.07.2018 | Transportation and Logistics
16.07.2018 | Agricultural and Forestry Science