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Barboza M, Kallaway K. Gross and microanatomic description of the dental pads of the Florida manatee, Trichechus manatus latirostris, and their importance to mastication. Arch Oral Biol 2024; 158:105871. [PMID: 38128336 DOI: 10.1016/j.archoralbio.2023.105871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 12/01/2023] [Accepted: 12/11/2023] [Indexed: 12/23/2023]
Abstract
OBJECTIVE Florida manatee feeding ecology is critical to species survival, but the role of dental pads in feeding has received limited attention. This study characterized the gross and microscopic anatomy of the manatee's dorsal and ventral dental pad in relation to these structures' importance in mastication, which furthers our understanding of manatee feeding and health. DESIGN Whole heads from 6 animals (4 male and 2 female) of varying sizes were examined grossly. Sections (5 µm) from throughout the dorsal and ventral dental pads were stained with Hematoxylin and Eosin to document microanatomy. The thickness of the epithelium and stratum corneum were measured. RESULTS The ventral dental pad epidermal (1129-3391 µm) and stratum corneum (331-1848 µm) thickness increased with increased body size. The dorsal dental pad epidermal (690-1988 µm) and stratum corneum (121-974 µm) thickness varied relative to size. The dental pad anatomy, including the thickened stratum corneum, indicates an importance similar to molars in grinding and physically breaking up plant material. Extensive appendages including filiform-like papillae and well-developed rete were observed and likely provide physical support for mastication. CONCLUSION While the sample size limits specific conclusions based on sex or age, it provides a good overview of the anatomy of the dental pads. The manatee is the only mammal known to have a ventral dental pad and the well-developed grinding surfaces demonstrates a crucial role in mastication for these structures. These dental pads should be evaluated during health checks and necropsies and considered in future research on manatee's feeding mechanisms.
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Affiliation(s)
- Meghan Barboza
- Southern Connecticut State University, 501 Crescent Street, New Haven, CT 06515, USA.
| | - Kiara Kallaway
- Atkins Engineering Consulting, 482 S Keller Rd, Orlando, FL 32810, USA.
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2
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Clauss M, Fritz J, Hummel J. Teeth and the gastrointestinal tract in mammals: when 1 + 1 = 3. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220544. [PMID: 37839451 PMCID: PMC10577037 DOI: 10.1098/rstb.2022.0544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 06/02/2023] [Indexed: 10/17/2023] Open
Abstract
Both teeth and the digestive tract show adaptations that are commonly interpreted in the context of trophic guilds-faunivory, herbivory and omnivory. Teeth prepare food for the digestive tract, and dental evolution focuses on increasing durability and functionality; in particular, size reduction of plant particles is an important preparation for microbial fermentative digestion. In narratives of digestive adaptations, microbes are typically considered as service providers, facilitating digestion. That the majority of 'herbivorous' (and possibly 'omnivorous') mammals display adaptations to maximize microbes' use as prey-by harvesting the microbes multiplying in their guts-is less emphasized and not reflected in trophic labels. Harvesting of microbes occurs either via coprophagy after separation from indigestible material by a separation mechanism in the hindgut, or from a forestomach by a 'washing mechanism' that selectively removes fines, including microbes, to the lower digestive tract. The evolution of this washing mechanism as part of the microbe farming niche opened the opportunity for the evolution of another mechanism that links teeth and guts in an innovative way-the sorting and cleaning of not-yet-sufficiently-size-reduced food that is then re-submitted to repeated mastication (rumination), leading to unprecedented chewing and digestive efficiency. This article is part of the theme issue 'Food processing and nutritional assimilation in animals'.
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Affiliation(s)
- Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Julia Fritz
- Zugspitzstr. 15 1/2, 82131 Stockdorf, Germany
| | - Jürgen Hummel
- Ruminant Nutrition, Department of Animal Sciences, University of Göttingen, Kellnerweg 6, 37077 Göttingen, Germany
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Ercoli MD, Álvarez A, Moyano SR. Masticatory myology of the llama (Lama glama, Camelidae) and comparisons with other camelids and euungulates. J Anat 2023; 243:770-785. [PMID: 37289996 PMCID: PMC10557395 DOI: 10.1111/joa.13891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 05/16/2023] [Accepted: 05/16/2023] [Indexed: 06/10/2023] Open
Abstract
Camelids are the only living representatives of the Suborder Tylopoda, and present a unique set of osteo-myological masticatory features, differing from all other extant euungulates. They combine selenodont dentition and rumination with a fused symphysis, and roughly plesiomorphic muscle proportions. Despite its potential relevance as an euungulate model in comparative anatomy studies, the available data is strikingly scarce. The present study represents the first description of the masticatory muscles of a Lamini, analyzing the functional morphology of Lama glama and other camelids in a comparative framework. Both sides of the head of three adult specimens from Argentinean Puna were dissected. Descriptions, illustrations, muscular maps, and weighing of all masticatory muscles were performed. Some facial muscles are also described. The myology of llamas confirms that camelids possess relatively large temporalis muscles, with Lama being less extreme than Camelus. This plesiomorphic feature is also recorded in suines and some basal euungulates. Conversely, the direction of the fibers of the M. temporalis is mainly horizontal, resembling grinding euungulates such as equids, pecorans, and some derived suines. Although the M. masseter of camelids and equids do not reach the particularly modified configuration of pecorans, in which it is rostrally extended and arranged horizontally, the posterior sectors of Mm. masseter superficialis and pterygoideus medialis have acquired relatively horizontal disposition in the former lineages, suitable for protraction. The pterygoidei complex presents several bundles, and its relative size is intermediate between suines and derived grinding euungulates. The whole masticatory muscles are relatively light when compared to jaw weight. The evolution of the masticatory muscles and chewing of camelids implied that grinding abilities were reached with less extreme modifications of the topography and/or proportions than pecoran ruminants and equids. A relatively large M. temporalis recruited as a powerful retractor during the power stroke is a key feature of camelids. The relaxed pressure on chewing derived from the acquisition of rumination explains the slenderer build masticatory musculature of camelids compared to other euungulates except ruminants.
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Affiliation(s)
- Marcos D Ercoli
- Instituto de Ecorregiones Andinas (CONICET-UNJu), San Salvador de Jujuy, Argentina
- Laboratorio de Paleontología de Vertebrados, Instituto de Geología y Minería (UNJu), San Salvador de Jujuy, Argentina
| | - Alicia Álvarez
- Instituto de Ecorregiones Andinas (CONICET-UNJu), San Salvador de Jujuy, Argentina
- Laboratorio de Paleontología de Vertebrados, Instituto de Geología y Minería (UNJu), San Salvador de Jujuy, Argentina
| | - S Rocío Moyano
- Instituto de Ecorregiones Andinas (CONICET-UNJu), San Salvador de Jujuy, Argentina
- Centro de Estudios Territoriales Ambientales y Sociales (UNJu), San Salvador de Jujuy, Argentina
- Instituto de Datación y Arqueometría (CONICET-Gobierno de Jujuy-UNT-UNJu-CNEA), Palpalá, Jujuy, Argentina
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Przybyło M, Krajda G, Różański Ł, Rolik G, Ortmann S, Górka P, Clauss M. Fluid and particle retention in a small New World and a small Old World cervid, the southern pudu (Pudu puda) and Reeves's muntjac (Muntiacus reevesi). Comp Biochem Physiol A Mol Integr Physiol 2023; 285:111506. [PMID: 37595882 DOI: 10.1016/j.cbpa.2023.111506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/15/2023] [Accepted: 08/15/2023] [Indexed: 08/20/2023]
Abstract
Ruminants differ in the pattern how small particles and liquids pass through their gastrointestinal tract, and in particular their reticulorumen (RR). Based on that they may be classified into 'moose-type' and 'cattle-type' species (smaller and larger differences between particle and liquid passage, respectively). The ratio between the retention of particles and fluids is called the 'selectivity factor' (SF) and is a species-specific characteristic, studied in tragulids, giraffids and bovids, but not in many cervid species. Recently, it has been suggested that a high SF might also serve to wash digesta clean of external abrasives prior to regurgitation for rumination. In this study, we measured SF and passage kinetics (using a liquid marker and markers of different particle size, fed with the diet) in a capreoline deer, the southern pudu (Pudu puda, n = 5, 10.3 ± 2.9 kg, kept at two zoos) and a cervine deer, the Reeves's muntjac (Muntiacus reevesi, n = 6, 11.0 ± 1.7 kg, kept at a research facility). The relative daily dry matter intake (38 ± 3 g/kg0.75 for pudu and 76 ± 5 g/kg0.75 for muntjac) was higher, and the mean retention times (MRT) correspondingly shorter (e.g., MRT small particles in the total digestive tract 39 ± 8 h for pudu and 15 ± 2 h for muntjac), in the muntjac. The SF for small particles/liquid in the reticulorumen were, however, similar for both species, at 1.47 ± 0.21 for pudu and 1.66 ± 0.20 for muntjac, indicating a 'moose-type' physiology for both, irrespective of their different phylogenetic origin. To date, SF recorded in bovids attain distinctively higher values than the few reported for cervids. This situation reflects the degree of hypsodonty (tooth crown height) attained by these taxa, which is higher in bovids than in cervids. Together, constraints in hypsodonty as well as SF might limit cervids to more mesic habitats without distinct loads of external abrasives (such as dust or grit) on their food. In both species, some animals showed the typical ruminant pattern of a longer MRT for large than for small particle markers, but in some animals, this difference was not evident. This may be due to variable degrees of marker chewing during ingestion.
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Affiliation(s)
- Marcin Przybyło
- Department of Animal Nutrition and Biotechnology, and Fisheries, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland.
| | - Gracja Krajda
- Department of Animal Nutrition and Biotechnology, and Fisheries, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland
| | - Łukasz Różański
- Municipal Zoological Garden in Warsaw, Ratuszowa 1/3, 03-461 Warszawa, Poland.
| | | | - Sylvia Ortmann
- Leibniz-Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Str. 17, 10315 Berlin, Germany.
| | - Paweł Górka
- Department of Animal Nutrition and Biotechnology, and Fisheries, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland.
| | - Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zürich, Switzerland.
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Clauss M, Codron D, Hummel J. Equid nutritional physiology and behavior: an evolutionary perspective. J Equine Vet Sci 2023; 124:104265. [PMID: 36893821 DOI: 10.1016/j.jevs.2023.104265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 02/18/2023] [Accepted: 02/23/2023] [Indexed: 03/11/2023]
Abstract
Like other members of the even-toed ungulates (the perissodactyls), equids once had a higher species diversity in the fossil record than they have today. This is generally explained in comparison to the enormous diversity of bovid ruminants. Theories on putative competitive disadvantages of equids include the use of a single toe as opposed to two toes per leg, the lack of a specific brain cooling (and hence water-saving) mechanism, longer gestation periods that delay reproductive output, and in particular digestive physiology. To date, there is no empirical support for the theory that equids fare better on low-quality forage than ruminants. In contrast to the traditional juxtaposition of hindgut and foregut fermenters, we suggest that it is more insightful to sketch the evolution of equid and ruminant digestive physiology as a case of convergence: both evolved a particularly high chewing efficacy in their respective groups, which facilitates comparatively high feed and hence energy intakes. But because the ruminant system, less based on tooth anatomy but more on a forestomach sorting mechanism, is more effective, equids depend more on high feed intakes than ruminants and may well be more susceptible to feed shortages. Arguably, the most under-emphasized characteristic of equids may be that in contrast to many other herbivores including ruminants and coprophageous hindgut fermenters, equids do not use the microbial biomass growing in their gastrointestinal tract. Equids display behavioral and morphophysiological adaptations to high feed intakes, and their cranial anatomy that facilitates the cropping of forage while performing grinding chewing at the same time might be unique. Rather than looking for explanations how equids are better adapted to their present niches than other organisms, considering them remnants of a different morphophysiological solution may be more appropriate.
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Affiliation(s)
- Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich; 8057 Zurich, Switzerland.
| | - Daryl Codron
- Department of Zoology and Entomology, University of the Free State; Bloemfontein, South Africa.
| | - Jürgen Hummel
- Ruminant Nutrition, Department of Animal Sciences, University of Goettingen; 37077 Goettingen, Germany.
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Zhang X, Li Y, Terranova M, Ortmann S, Kreuzer M, Hummel J, Clauss M. Individual differences in digesta retention and their relation to chewing in cattle-A pilot investigation. J Anim Physiol Anim Nutr (Berl) 2023; 107:394-406. [PMID: 35560728 DOI: 10.1111/jpn.13733] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/28/2022] [Accepted: 04/22/2022] [Indexed: 01/25/2023]
Abstract
While information on individual differences in digesta mean retention time (MRT) might be interesting when selecting phenotypes for digestive efficiency, MRT measurements are prohibitively labour-intensive for large-scale application. Therefore, more easily measured proxies of MRT might be helpful. We used the opportunity of an experiment applying saliva stimulant in cattle to investigate the effect of different individual chewing behaviour on fluid and particle MRT with a consistent diet. Four non-lactating cattle (670-850 kg body mass [BM]) were used in a 4 × 4 Latin square design, treated with the saliva stimulant pilocarpine in dosages of 0, 1, 2.5 and 5 mg/kg BM per day. The cattle were fed hay with dry matter intake (DMI) assigned according to their metabolic body weight. MRT in the whole gastrointestinal tract (GIT), the reticulorumen (RR) and the distal tract were measured using Co-EDTA, Cr-mordanted fibre and La-mordanted fibre as markers representing fluid, small particles (2 mm) and large particles (1 cm), respectively. The chewing behaviour was measured via noseband pressure sensor and expressed as chewing frequency (chews per time) and chewing intensity (chews per DMI), both for total chewing (ingestion plus rumination) and rumination chewing alone. The animals differed considerably in chewing behaviour and MRT measures. BM did not show a significant effect on chewing behaviour and MRT measures, though it tended to negatively correlated to total chewing intensity. Chewing intensity exerted a significant negative influence on MRT of fluid and particles in the RR, which was not the case for chewing frequency. Chewing frequency showed a significant relationship with MRT of large particles in the GIT. We suggest that chewing behaviour could influence MRT in two ways: (i) by affecting saliva production via the masticatory-salivary reflex and subsequently, the fluid inflow to the RR; (ii) by contributing to particle size reduction. Should the link between chewing behaviour and MRT be corroborated in larger studies, chewing measures, with their large interindividual variation, could emerge as an easy-to-measure proxy for MRT characteristics.
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Affiliation(s)
- Xiaoyu Zhang
- Department of Animal Sciences, Ruminant Nutrition, University of Göttingen, Göttingen, Germany
| | - Yang Li
- Institute of Agricultural Sciences, ETH Zurich, Lindau, Switzerland
| | | | - Sylvia Ortmann
- Leibniz Institute for Zoo and Wildlife Research (IZW), Berlin, Germany
| | - Michael Kreuzer
- Institute of Agricultural Sciences, ETH Zurich, Lindau, Switzerland
| | - Jürgen Hummel
- Department of Animal Sciences, Ruminant Nutrition, University of Göttingen, Göttingen, Germany
| | - Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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7
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Martin LF, Ackermans NL, Richter H, Kircher P, Hummel J, Codron D, Clauss M, Hatt J. Macrowear effects of external quartz abrasives of different size and concentration in rabbits (Oryctolagus cuniculus). JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2022; 338:586-597. [PMID: 34813148 PMCID: PMC9787991 DOI: 10.1002/jez.b.23104] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 10/27/2021] [Accepted: 10/30/2021] [Indexed: 12/30/2022]
Abstract
External quartz abrasives are one of the driving forces of macrowear in herbivorous animals. We tested to what extent different sizes and concentrations influence their effect on tooth wear. We fed seven pelleted diets varying only in quartz concentration (0%, 4%, and 8%) and size (fine silt: ∼4 μm, coarse silt: ∼50 μm, fine sand: ∼130 μm) to rabbits (Oryctolagus cuniculus, n = 16) for 2 weeks each in a randomized serial experiment. Measurements to quantify wear and growth of incisors and the mandibular first cheek tooth, as well as heights of all other cheek teeth, were performed using calipers, endoscopic examination, and computed tomography scans before and after each feeding period. Tooth growth showed a compensatory correlation with wear. Absolute tooth height (ATH) and relative tooth height (RTH); relative to the 0% quartz "control" diet) was generally lower on the higher concentration and the larger size of abrasives. The effect was more pronounced on the maxillary teeth, on specific tooth positions and the right jaw side. When offered the choice between different sizes of abrasives, the rabbits favored the silt diets over the control and the fine sand diet; in a second choice experiment with different diets, they selected a pelleted diet with coarse-grained sand, however. This study confirms the dose- and size-dependent wear effects of external abrasives, and that hypselodont teeth show compensatory growth. The avoidance of wear did not seem a priority for animals with hypselodont teeth, since the rabbits did not avoid diets inducing a certain degree of wear.
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Affiliation(s)
- Louise F. Martin
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
| | - Nicole L. Ackermans
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland,Present address:
Nicole L. Ackermans, Nash Family Department of Neuroscience, Friedman Brain Institute, Center for Anatomy and Functional MorphologyIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Henning Richter
- Clinic for Diagnostic Imaging, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
| | - Patrick Kircher
- Clinic for Diagnostic Imaging, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
| | - Jürgen Hummel
- Divison of Ruminant Nutrition, Department of Animal SciencesUniversity of GoettingenGoettingenGermany
| | - Daryl Codron
- Department of Zoology and EntomologyUniversity of the Free StateBloemfonteinSouth Africa
| | - Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
| | - Jean‐Michel Hatt
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
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Fannin LD, Laugier EJ, van Casteren A, Greenwood S, Dominy NJ. Differentiating siliceous particulate matter in the diets of mammalian herbivores. Methods Ecol Evol 2022. [DOI: 10.1111/2041-210x.13934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luke D. Fannin
- Department of Anthropology Dartmouth College Hanover NH USA
- Graduate Program in Ecology, Evolution, Environment, and Society Dartmouth College Hanover NH USA
| | - Elise J. Laugier
- Department of Anthropology Dartmouth College Hanover NH USA
- Graduate Program in Ecology, Evolution, Environment, and Society Dartmouth College Hanover NH USA
| | - Adam van Casteren
- School of Biological Sciences University of Manchester Manchester UK
| | - Sabrina L. Greenwood
- Department of Animal and Veterinary Sciences University of Vermont Burlington VT USA
| | - Nathaniel J. Dominy
- Department of Anthropology Dartmouth College Hanover NH USA
- Department of Biological Sciences Dartmouth College Hanover NH USA
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Foley AM, Lewis JS, Cortez O, Hellickson MW, Hewitt DG, DeYoung RW, DeYoung CA, Schnupp MJ. Accuracies and biases of ageing white-tailed deer in semiarid environments. WILDLIFE RESEARCH 2021. [DOI: 10.1071/wr21050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Abstract Context The ability to accurately estimate age of animals is important for both research and management. The two methods for age estimation in ungulates are tooth replacement and wear (TRW) and cementum annuli (CA). Errors in estimated TRW ages are commonly attributed to environmental conditions; however, the influence of environmental variables on tooth wear has not been quantified. Further, the performance of CA in environments with weak seasonality has not been thoroughly evaluated. Aims The study had the following three goals: identify environmental and morphological factors that influenced estimated ages, quantify accuracy of TRW and CA, and develop TRW ageing criteria that minimise error. Methods We used data from harvested (n = 5117) and free-ranging, known-age white-tailed deer (n = 134) collected in southern Texas, USA, to quantify environmental and morphological influences on estimated TRW ages, and assess biases in both methods. Key results We observed substantial variation in age estimates for both TRW and CA. Soil, drought and supplemental nutrition had minor effects on tooth wear, insufficient to alter age estimates by ≥1 year. Body mass and antler size influenced age estimates for TRW only for extreme outliers. Both methods were biased and tended to under-estimate ages of adult deer, especially TRW. Wear on the first molar was most correlated with the known age (r2 = 0.78) and allowed biologists to correctly place known-age deer into age classes of 2, 3–5, and ≥6 years old 72%, 73% and 68% of the time, an improvement compared with the 79%, 48% and 28% accuracy from pooled TRW. Conclusions We observed substantial inter- and intra-individual variation in tooth-wear patterns that became more pronounced in older deer. Individual variation had a greater influence on TRW ages than did environmental covariates, whereas CA ages appeared unaffected by environment. Although variable, age estimates were ±1 year of the true age 87% and 93% of the time for TRW and CA respectively. Implications Managers, ecologists and epidemiologists often incorporate ages into population models. The high inter-individual variation in estimated ages, the tendency to underestimate ages of older deer, and the ageing method need to be considered.
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Findeisen E, Südekum K, Fritz J, Hummel J, Clauss M. Increasing food intake affects digesta retention, digestibility and gut fill but not chewing efficiency in domestic rabbits (Oryctolagus cuniculus). JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2021; 335:614-622. [PMID: 34254468 PMCID: PMC8362112 DOI: 10.1002/jez.2505] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 05/25/2021] [Accepted: 06/25/2021] [Indexed: 01/23/2023]
Abstract
In ruminants, the level of food intake affects net chewing efficiency and hence faecal particle size. For nonruminants, corresponding data are lacking. Here, we report the effect of an increased food intake of a mixed diet in four domestic rabbit does due to lactation, and assess changes in particle size (as determined by wet sieving analysis) along the rabbit digestive tract. During lactation, rabbits achieved a distinctively higher dry matter intake than at maintenance, with a concomitant reduction in mean retention times of solute and particle markers, an increase in dry matter gut fill, a reduction in apparent digestibility of dry matter, and an overall increase in digestible dry matter intake. By contrast, there was no change in faecal mean particle size (mean ± SD: 0.58 ± 0.02 vs. 0.56 ± 0.01 mm). A comparison of diet, stomach content and faecal mean particle size suggested that 98% of particle size reduction occurred due to ingestive mastication and 2% due to digestive processes. Very fine particles passing the finest sieve, putatively not only of dietary but mainly of microbial origin, were particularly concentrated in caecum contents, which corresponds to retention of microbes via a 'wash-back' colonic separation mechanism, to concentrate them in caecotrophs that are re-ingested. This study gives rise to the hypothesis that chewing efficiency on a consistent diet is not impaired by intake level in nonruminant mammals.
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Affiliation(s)
- Eva Findeisen
- Institute of Animal Science, Animal NutritionUniversity of BonnBonnGermany
- Present address:
Hostertsweg 18Grafschaft53501Germany
| | - Karl‐Heinz Südekum
- Institute of Animal Science, Animal NutritionUniversity of BonnBonnGermany
| | | | - Jürgen Hummel
- Ruminant Nutrition, Department of Animal SciencesUniversity of GoettingenGoettingenGermany
| | - Marcus Clauss
- Clinic für Zoo Animals, Exotic Pets and Wildlife, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
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11
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Hatt JM, Codron D, Richter H, Kircher PR, Hummel J, Clauss M. Preliminary evidence for a forestomach washing mechanism in llamas ( Lama glama). Mamm Biol 2021; 101:941-948. [PMID: 34924918 PMCID: PMC8629863 DOI: 10.1007/s42991-021-00142-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 06/04/2021] [Indexed: 10/29/2022]
Abstract
Dust and grit are ingested by herbivores in their natural habitats along with the plants that represent their selected diet. Among the functions of the rumen, a washing of ingesta from adhering dust and grit has recently been demonstrated. The putative consequence is a less strenuous wear on ruminant teeth by external abrasives during rumination. The same function should theoretically apply to camelids, but has not been investigated so far. We fed six llamas (Lama glama) a diet of grass hay and a lucerne-based pelleted food in which fine sand had been included at about 8% of ingredients, for ad libitum consumption for 6 weeks. Subsequently, animals were slaughtered and content of the different sections of the gastrointestinal tract was sampled for the analysis of dry matter (DM), total ash, and acid detergent insoluble ash (ADIA, a measure for silica). Additionally, two of the animals were subjected to whole-body computer tomography (CT) after death in the natural sternal resting position. No clinical problems or macroscopic changes in the faeces were observed during the experimental period. The results indicate an accumulation of ADIA in the C3 compartment of the stomach complex, in particular in the posterior portion that is the equivalent of the abomasum in ruminants. By contrast, contents of the C1, from which material is recruited for regurgitation and rumination, were depleted of ADIA, indicating that the contents had largely been washed free of sand. The washing effect is an unavoidable side effect of the flotation- and sedimentation-based sorting mechanisms in the ruminant and the camelid forestomachs. In theory, this should allow ruminants and camelids to live in similar habitats as nonruminant herbivores at lower degrees of hypsodonty.
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Affiliation(s)
- Jean-Michel Hatt
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, Winterthurerstr. 260, 8057 Zurich, Switzerland
| | - Daryl Codron
- Department of Zoology and Entomology, University of the Free State, PO Box 339, Bloemfontein, 9300 South Africa
| | - Henning Richter
- Clinic for Diagnostic Imaging, Vetsuisse Faculty, University of Zurich, Winterthurerstr. 258c, 8057 Zurich, Switzerland
| | - Patrick R. Kircher
- Clinic for Diagnostic Imaging, Vetsuisse Faculty, University of Zurich, Winterthurerstr. 258c, 8057 Zurich, Switzerland
| | - Jürgen Hummel
- Ruminant Nutrition, Department of Animal Sciences, University of Goettingen, Kellnerweg 6, 37077 Göttingen, Germany
| | - Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, Winterthurerstr. 260, 8057 Zurich, Switzerland
- AgroVet Strickhof, Lindau Site, Eschikon 27, 8315 Lindau, Switzerland
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12
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Findeisen E, Südekum KH, Hummel J, Clauss M. Increasing feed intake in domestic goats (Capra hircus): Measured effects on chewing intensity are probably driven by escape of few, large particles from the forestomach. Comp Biochem Physiol A Mol Integr Physiol 2021; 257:110972. [PMID: 33940177 DOI: 10.1016/j.cbpa.2021.110972] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 04/26/2021] [Accepted: 04/27/2021] [Indexed: 11/16/2022]
Abstract
On the one hand, oral processing - mastication - is considered a relatively inflexible component of mammalian feed acquisition that constrains instantaneous intake rates. On the other hand, experimental data shows that the level of feed intake affects faecal particle size and hence net chewing efficiency in ruminants, with larger particles occurring in the faeces at higher intakes. Here, we report the effect of an increased feed intake during maintenance (L1), late (200% of L1) and peak lactation (300% of L1) of a consistent diet (hay:concentrates 50:50) in eight domestic goats on various measures of digestive physiology including faecal mean particle size (MPS). Increasing intake led to an increased gut fill, a reduction in digesta retention times, and an increase in faecal MPS (from 0.57 to 0.72 mm). However, this was an effect of the large particle fraction (>2 mm) being disproportionately excreted at higher intakes; if MPS was assessed on the basis of particles below the typical escape threshold (≤1 mm), there was no difference between intake levels. These findings suggest that the effect of intake on the calculated net chewing efficiency in ruminants may rather be an effect of increased large particle escape from the forestomach than a reduced chewing intensity per bolus during ingestion or rumination.
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Affiliation(s)
- Eva Findeisen
- Institute of Animal Science, University of Bonn, Endenicher Allee 15, 53115 Bonn, Germany
| | - Karl-Heinz Südekum
- Institute of Animal Science, University of Bonn, Endenicher Allee 15, 53115 Bonn, Germany.
| | - Jürgen Hummel
- Ruminant Nutrition, Department of Animal Sciences, University of Goettingen, Kellnerweg 6, 37077 Goettingen, Germany.
| | - Marcus Clauss
- Clinic für Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich,Winterthurerstr. 260, 8057 Zurich, Switzerland.
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13
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Ackermans NL, Winkler DE, Martin LF, Kaiser TM, Clauss M, Hatt JM. Dust and grit matter: abrasives of different size lead to opposing dental microwear textures in experimentally fed sheep ( Ovis aries). J Exp Biol 2020; 223:jeb220442. [PMID: 31953361 DOI: 10.1242/jeb.220442] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/09/2020] [Indexed: 11/20/2022]
Abstract
External abrasives ingested along with the herbivore diet are considered main contributors to dental wear, though how the different sizes and concentrations of these abrasives influence wear remains unclear. Dental microwear texture analysis (DMTA) is an established method for dietary reconstruction which describes a tooth's surface topography on a micrometre scale. The method has yielded conflicting results as to the effect of external abrasives. In the present study, a feeding experiment was performed on sheep (Ovis aries) fed seven diets of different abrasiveness. Our aim was to discern the individual effects of size (4, 50 and 130 µm) and concentration (0%, 4% and 8% of dry matter) of abrasives on dental wear, applying DMTA to four tooth positions. Microwear textures differed between individual teeth, but surprisingly, showed no gradient along the molar tooth row, and the strongest differentiation of experimental groups was achieved when combining data of all maxillary molars. Overall, a pattern of increasing height, volume and complexity of the tooth's microscopic surface appeared with increasing size of dietary abrasives, and when compared with the control, the small abrasive diets showed a polishing effect. The results indicate that the size of dietary abrasives is more important for dental microwear texture traces than their concentration, and that different sizes can have opposing effects on the dietary signal. The latter finding possibly explains conflicting evidence from previous experimental DMTA applications. Further exploration is required to understand whether and how microscopic traces created by abrasives translate quantitatively to tissue loss.
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Affiliation(s)
- Nicole L Ackermans
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland
| | - Daniela E Winkler
- Applied and Analytical Paleontology, Institute for Geosciences, Johannes Gutenberg University Mainz, 55099 Mainz, Germany
- Center of Natural History, University of Hamburg, 20146 Hamburg, Germany
| | - Louise F Martin
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland
| | - Thomas M Kaiser
- Center of Natural History, University of Hamburg, 20146 Hamburg, Germany
| | - Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland
| | - Jean-Michel Hatt
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland
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14
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15
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Bochnia M, Goetz F, Wensch-Dorendorf M, Koelln M, Zeyner A. Chewing patterns in horses during the intake of variable quantities of two pelleted compound feeds differing in their physical characteristics only. Res Vet Sci 2019; 125:189-194. [PMID: 31254716 DOI: 10.1016/j.rvsc.2019.06.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 05/29/2019] [Accepted: 06/19/2019] [Indexed: 11/28/2022]
Abstract
Pelleted feeds (PF) are popular in horse nutrition because of high palatability and improved feeding hygiene, but ingestion is faster for PF than for cereals or muesli feed. The aim of the study was to evaluate whether variable amounts of two PFs produced with different physical properties from the same batch of feed can affect feed intake patterns in horses. Chewing patterns were measured in six warmblood mares (519 ± 36.3 kg) on two PFs (small-sized PF1: ø 5 mm, length 21.9 ± 4.97 mm, large-sized PF2: edge length 15.6 ± 0.14 × 15.6 ± 0.08 mm, length 54.4 ± 9.59 mm) in three different amounts (1.0, 1.5, 2.0 kg) once per day additional to hay. PF 2 was ingested faster than PF1 for the meal size 1.0 kg, but PF 1 was ingested more rapidly with a reduced chewing intensity if the offered meal size increased. The ingestion of PF 2 tendentially elevated the chewing intensity at higher meal sizes. An additional, but inverted meal size effect compared to 1.0 kg, was observed for 1.5 kg, where PF 1 was ingested at a higher speed combined with a lower chewing intensity compared to PF 2. Independent from the offered amount, PF 2 induced a markedly increased saliva production combined with a higher daily water intake. Larger-sized pellets seem to intensify the chewing process and decelerate the ingestion time if the meal size becomes larger.
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Affiliation(s)
- Mandy Bochnia
- Group Animal Nutrition, Martin Luther University Halle-Wittenberg, Institute for Agricultural and Nutritional Sciences, Halle, Saale, Germany.
| | - Franziska Goetz
- Group Animal Nutrition, Martin Luther University Halle-Wittenberg, Institute for Agricultural and Nutritional Sciences, Halle, Saale, Germany
| | - Monika Wensch-Dorendorf
- Biometrics and Informatics in Agricultural Group, Martin Luther University Halle-Wittenberg, Institute for Agricultural and Nutritional Sciences, Halle, Saale, Germany
| | - Mareike Koelln
- University of Veterinary Medicine Hannover Foundation, Institute of Animal Nutrition, Hannover, Germany
| | - Annette Zeyner
- Group Animal Nutrition, Martin Luther University Halle-Wittenberg, Institute for Agricultural and Nutritional Sciences, Halle, Saale, Germany
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Ackermans NL, Martin LF, Hummel J, Müller DW, Clauss M, Hatt JM. Feeding selectivity for diet abrasiveness in sheep and goats. Small Rumin Res 2019. [DOI: 10.1016/j.smallrumres.2019.05.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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17
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Semprebon GM, Rivals F, Janis CM. The Role of Grass vs. Exogenous Abrasives in the Paleodietary Patterns of North American Ungulates. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00065] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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18
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Ackermans NL, Clauss M, Winkler DE, Schulz-Kornas E, Kaiser TM, Müller DWH, Kircher PR, Hummel J, Hatt JM. Root growth compensates for molar wear in adult goats (Capra aegagrus hircus). JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2018; 331:139-148. [PMID: 30511369 DOI: 10.1002/jez.2248] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 11/09/2018] [Accepted: 11/10/2018] [Indexed: 11/09/2022]
Abstract
One reason for the mammalian clade's success is the evolutionary diversity of their teeth. In herbivores, this is represented by high-crowned teeth evolved to compensate for wear caused by dietary abrasives like phytoliths and grit. Exactly how dietary abrasives wear teeth is still not understood completely. We fed four different pelleted diets of increasing abrasiveness (L: Lucerne; G: grass; GR: grass and rice husks; GRS: grass, rice husks, and sand) to four groups of a total of 28 adult goats, all with completely erupted third molars, over a six-month period. Tooth morphology was captured by medical computed tomography scans at the beginning and end of the controlled feeding experiment, and separation lines between the crown and root segments were defined in the upper right second molar (M2), to gauge absolute wear. Using bootstrapping, significant differences in volume loss between diets L/G and GR/GRS were detected. A small but nevertheless consistent volume gain was noted in the roots, and there was a significant, positive correlation between crown volume loss and root volume gain. This growth could possibly be attributed to the well-known process of cementum deposition and its relation with a putative feedback mechanism, in place to attenuate wear caused by abrasive diets.
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Affiliation(s)
- Nicole L Ackermans
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurih, Zurich, Switzerland
| | - Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurih, Zurich, Switzerland
| | - Daniela E Winkler
- Institute for Geosciences, Johannes Gutenberg University Mainz, Mainz, Germany.,Center of Natural History, University of Hamburg, Hamburg, Germany
| | - Ellen Schulz-Kornas
- Max Planck Weizmann Center for Integrative Archaeology and Anthropology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Center of Natural History, University of Hamburg, Hamburg, Germany
| | - Thomas M Kaiser
- Center of Natural History, University of Hamburg, Hamburg, Germany
| | | | - Patrick R Kircher
- Division of Diagnostic Imaging, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Jürgen Hummel
- Department of Animal Sciences, Ruminant Nutrition, Georg-August-University, Göttingen, Germany
| | - Jean-Michel Hatt
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurih, Zurich, Switzerland
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Ackermans NL, Winkler DE, Schulz-Kornas E, Kaiser TM, Müller DWH, Kircher PR, Hummel J, Clauss M, Hatt JM. Controlled feeding experiments with diets of different abrasiveness reveal slow development of mesowear signal in goats ( Capra aegagrus hircus). ACTA ACUST UNITED AC 2018; 221:jeb.186411. [PMID: 30194251 DOI: 10.1242/jeb.186411] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 09/05/2018] [Indexed: 11/20/2022]
Abstract
Dental mesowear is applied as a proxy to determine the general diet of mammalian herbivores based on tooth-cusp shape and occlusal relief. Low, blunt cusps are considered typical of grazers and high, sharp cusps typical of browsers. However, how internal or external abrasives impact mesowear, and the time frame the wear signature takes to develop, still need to be explored. Four different pelleted diets of increasing abrasiveness (lucerne, grass, grass and rice husks, and grass, rice husks and sand) were fed to four groups of a total of 28 adult goats in a controlled feeding experiment over a 6-month period. Tooth morphology was captured by medical CT scans at the beginning and end of the experiment. These scans, as well as the crania obtained post mortem, were scored using the mesowear method. Comparisons between diet groups showed few significant differences after 6 months, irrespective of whether CT scans or the real teeth were scored. Only when assessing the difference in signal between the beginning and the end of the experiment did relevant, significant diet-specific effects emerge. Diets containing lower phytolith content caused a more pronounced change in mesowear towards sharper cusps/higher reliefs, while the feed containing sand did not result in more extreme changes in mesowear when compared with the same feed without sand. Our experiment suggests that the formation of a stable and hence reliable mesowear signal requires more time to develop than 6 months.
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Affiliation(s)
- Nicole L Ackermans
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Daniela E Winkler
- Institute for Geosciences, Johannes Gutenberg University Mainz, 55099 Mainz, Germany.,Center of Natural History, University of Hamburg, 20146 Hamburg, Germany
| | - Ellen Schulz-Kornas
- Center of Natural History, University of Hamburg, 20146 Hamburg, Germany.,Max Planck Weizmann Center for Integrative Archaeology and Anthropology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Thomas M Kaiser
- Center of Natural History, University of Hamburg, 20146 Hamburg, Germany
| | - Dennis W H Müller
- Zoologischer Garten Halle GmbH, Fasanenstr. 5a, 06114 Halle (Saale), Germany
| | - Patrick R Kircher
- Division of Diagnostic Imaging, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Jürgen Hummel
- Department of Animal Sciences, Ruminant Nutrition, Georg-August University, 37073 Göttingen, Germany
| | - Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Jean-Michel Hatt
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
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20
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Dietary exogenous and endogenous abrasives and tooth wear in African buffalo. BIOSURFACE AND BIOTRIBOLOGY 2017. [DOI: 10.1016/j.bsbt.2017.12.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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21
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Hummel J, Scheurich F, Ortmann S, Crompton LA, Gerken M, Clauss M. Comparative selective retention of particle size classes in the gastrointestinal tract of ponies and goats. J Anim Physiol Anim Nutr (Berl) 2017; 102:429-439. [PMID: 28696048 DOI: 10.1111/jpn.12763] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 05/08/2017] [Indexed: 11/28/2022]
Abstract
There is a discrepancy in the literature on potential digesta separation mechanisms in horses, with both a selective retention of fine and of large particles postulated in different publications. To assess the net effect of such mechanisms, we fed ponies on a hay-only diet a pulse dose of whole (unchopped) marked hay together with a solute marker, collected faeces on a regular basis, measured marker concentrations in whole faeces and in their large (2.0-16 mm), medium (0.5-1.0 mm) and small (0.063-0.25 mm) particle fraction, and calculated the corresponding mean retention times (MRTs). For comparison, the same experiment was performed in goats. In goats, as expected, MRTsolute (35 hr) was significantly shorter than MRTparticle (51 hr); only a very small fraction of particle marker was excreted as large particles (2%); and the MRT of these large particles was significantly shorter than that of small particles (with a relevant difference of 8.6 hr), indicating that those few large particles that escape the rumen do so mostly soon after ingestion. In ponies, MRTsolute (24 hr) did not differ from MRTparticle (24 hr); a higher fraction of particle marker was excreted as large particles (5%); and the MRT of these large particles was longer than that of small particles (but with a non-relevant difference of less than 1 hr). These results indicate that no relevant net separation of digesta phases occurs in horses and that selective particle retention mechanisms in the large intestine are unlikely to represent important characteristics of the horse's digestive physiology.
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Affiliation(s)
- J Hummel
- Department of Animal Sciences, University of Göttingen, Göttingen, Germany
| | - F Scheurich
- Department of Animal Sciences, University of Göttingen, Göttingen, Germany
| | - S Ortmann
- Leibniz Institute for Zoo and Wildlife Research (IZW), Berlin, Germany
| | - L A Crompton
- Sustainable Agriculture and Food Systems Research Division, Centre for Dairy Research, School of Agriculture, Policy and Development, University of Reading, Reading, UK
| | - M Gerken
- Department of Animal Sciences, University of Göttingen, Göttingen, Germany
| | - M Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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