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The ungulates of northern China
Wu Jia-yan
Rangifer , 1994,
Abstract: Presently, thirty five species of ungulates occur in northern China. Some species are threatened or endangered. There are three species of Equidae (E. przewalskii, E. hemionus, E. kiang), one of Suidae (Sus scrofa), one of Camelidae (Camelus bactrianus), 14 species of Cervidae (with the genera Moschus, Elaphus, Cervus, Elaphurus, Alces, Rangifer, Capreolus) and 16 species of Bovidae (within the genera Bos, Gazella, Procapra, Pantholops, Saiga, Nemorhaedus, Capricornis, Budorcas, Capra, Pseudois, Ovis). They inhabit different biotopes, i.e. temperate mountain forest and steppe, temperate desert and semi-desert, and vast alpine ranges. Ungulate fossils are widespread in China evidencing that Asia was an evolutionary centre for some ungulates. Although new data have been gathered through research efforts in China since 1949 it is a fact that some ungulate species have suffered serious population set-backs and some have become endangered or even extinct. Detailed studies of ungulate populations and protection of habitats are now most important future research needs.
Are arctic ungulates physiologically unique?
James M. Suttie,James R. Webster
Rangifer , 1998,
Abstract: Reindeer/caribou (Rangifer tarandus) and muskoxen (Ovibos moschatus) are the arctic ungulates. Few studies have been carried out to directly compare their level of physiological uniqueness with similar species in the same family. The approach adopted in this review has been to compare data within family for physiological parameters including reproduction, nutrition and growth, to attempt to place the adaptations of reindeer/caribou and muskoxen in context. It is concluded that both species have unique adaptations to their environment which are likely to be specific to the Arctic. An hypothesis is advanced that some adaptations are constrained not only by the long intense winters, but also by the need to exploit the brief summers. The review has highlighted considerable gaps in understanding of some key physiological parameters for many species. This incompleteness in some ways mitigated the original goal of the project, but provisional conclusions are presented.
Survival strategies in arctic ungulates
N. J. C. Tyler,A. S. Blix
Rangifer , 1990,
Abstract: Arctic ungulates usually neither freeze nor starve to death despite the rigours of winter. Physiological adaptations enable them to survive and reproduce despite long periods of intense cold and potential undernutrition. Heat conservation is achieved by excellent insulation combined with nasal heat exchange. Seasonal variation in fasting metabolic rate has been reported in several temperate and sub-arctic species of ungulates and seems to occur in muskoxen. Surprisingly, there is no evidence for this in reindeer. Both reindeer and caribou normally maintain low levels of locomotor activity in winter. Light foot loads are important for reducing energy expenditure while walking over snow. The significance and control of selective cooling of the brain during hard exercise (e.g. escape from predators) is discussed. Like other cervids, reindeer and caribou display a pronounced seasonal cycle of appetite and growth which seems to have an intrinsic basis. This has two consequences. First, the animals evidently survive perfectly well despite enduring negative energy balance for long periods. Second, loss of weight in winter is not necessarily evidence of undernutrition. The main role of fat reserves, especially in males, may be to enhance reproductive success. The principal role of fat reserves in winter appears to be to provide a supplement to, rather than a substitute for, poor quality winter forage. Fat also provides an insurance against death during periods of acute starvation.
Viral diseases of northern ungulates
K. Fr?lich
Rangifer , 2000,
Abstract: This paper describes viral diseases reported in northern ungulates and those that are a potential threat to these species. The following diseases are discussed: bovine viral diarrhoea/mucosal disease (BVD/MD), alphaherpesvirus infections, malignant catarrhal fever (MCF), poxvirus infections, parainfluenza type 3 virus infection, Alvsborg disease, foot-and-mouth disease, epizootic haemorrhage disease of deer and bluetongue disease, rabies, respiratory syncytial virus infection, adenovirus infection, hog-cholera, Aujeszky's disease and equine herpesvirus infections. There are no significant differences in antibody prevalence to BVDV among deer in habitats with high, intermediate and low density of cattle. In addition, sequence analysis from the BVDV isolated from roe deer (Capreolus capreolus) showed that this strain was unique within BVDV group I. Distinct BVDV strains might circulate in free-ranging roe deer populations in Germany and virus transmission may be independent of domestic livestock. Similar results have been obtained in a serological survey of alpha-herpesviruses in deer in Germany. Malignant catarrhal fever was studied in fallow deer (Cervus dama) in Germany: the seroprevalence and positive PCR results detected in sheep originating from the same area as the antibody-positive deer might indicate that sheep are the main reservoir animals. Contagious ecthyma (CE) is a common disease in domestic sheep and goats caused by the orf virus. CE has been diagnosed in Rocky Mountain bighorn sheep (Ovis canadensis), mountain goats (Oreamnos americanus), Dall sheep (Ovis dalli), chamois (Rupkapra rupi-capra), muskox {Ovibos moschatus) and reindeer (Rangifer tarandus). Most parainfluenza type 3 virus infections are mild or clinically undetectable. Serological surveys in wildlife have been successfully conducted in many species. In 1985, a new disease was identified in Swedish moose (Alces alces), designated as Alvsborg disease. This wasting syndrome probably has a multi-factorial etiology. Foot-and-mouth disease virus (FMDV) can infect deer and many other wild artiodactyls. Moose, roe deer and the saiga antelope (Saiga tatarica) are the main hosts of FMDV in the Russian Federation. In addition, serological evidence of a FMD infection without clinical disease was detected in red deer in France. Epizootic haemorrhage disease of deer (EHD) and bluetongue (BT) are acute non-contagious viral diseases of wild ruminants characterised by extensive haemorrhage. Culicoides insects are the main vectors. EHD and BT only play a minor role in Europe but both diseases a
The fine structure of 321 avoiding involutions  [PDF]
Piera Manara,Claudio Perelli Cippo
Mathematics , 2010,
Abstract: We study the involutions belonging to the class of 321 avoiding permutations. We calculate the algebraic generating functions of the set containing the involutions avoiding 321 and of some of its subsets. Precisely we determine the algebraic generating functions of the involutions that are expansions of 12, of those expansions of 21, of the simple ones and of their expansions. The graphics of the simple involutions are caracterized. Being the simple involutions avoiding 321 counted by Riordan's numbers, a combinatoric interpretation of the results is illustrated through a class of Motzkin paths. Another interpretation is given through Dyck paths.
The fine structure of 321 avoiding permutations  [PDF]
Michael H. Albert
Mathematics , 2002,
Abstract: Bivariate generating functions for various subsets of the class of permutations containing no descending sequence of length three or more are determined. The notion of absolute indecomposability of a permutation is introduced, and used in enumerating permutations which have a block structure avoiding 321 and whose blocks also have such structure (recursively). Generalizations of these results are discussed.
Reassessing the Determinants of Breeding Synchrony in Ungulates  [PDF]
Annie K. English, Aliénor L. M. Chauvenet, Kamran Safi, Nathalie Pettorelli
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0041444
Abstract: Predicting the consequences of climate change is a major challenge in ecology and wildlife management. While the impact of changes in climatic conditions on distribution ranges has been documented for many organisms, the consequences of changes in resource dynamics for species' overall performance have seldom been investigated. This study addresses this gap by identifying the factors shaping the reproductive synchrony of ungulates. In temporally-variable environments, reproductive phenology of individuals is a key determinant of fitness, with the timing of reproduction affecting their reproductive output and future performance. We used a satellite-based index of resource availability to explore how the level of seasonality and inter-annual variability in resource dynamics affect birth season length of ungulate populations. Contrary to what was previously thought, we found that both the degree of seasonal fluctuation in resource dynamics and inter-annual changes in resource availability influence the degree of birth synchrony within wild ungulate populations. Our results highlight how conclusions from previous interspecific analyses, which did not consider the existence of shared life-history among species, should be treated with caution. They also support the existence of a multi-faceted link between temporal variation in resource availability and breeding synchrony in terrestrial mammals, and increase our understanding of the mechanisms shaping reproductive synchrony in large herbivores, thus enhancing our ability to predict the potential impacts of climate change on biodiversity.
Growth rates for subclasses of Av(321)  [PDF]
M. H. Albert,M. D. Atkinson,R. Brignall,N. Ruskuc,Rebecca Smith,J. West
Mathematics , 2009,
Abstract: Pattern classes which avoid 321 and other patterns are shown to have the same growth rates as similar (but strictly larger) classes obtained by adding articulation points to any or all of the other patterns. The method of proof is to show that the elements of the latter classes can be represented as bounded merges of elements of the original class, and that the bounded merge construction does not change growth rates.
Assessment of Wild Ungulates in the Karnali Flood Plain of Bardia National Park, Nepal  [PDF]
Daya Nidhi GAUTAM
International Journal of Conservation Science , 2013,
Abstract: The population of ungulates depends on the habitat factors and prey-predator interaction. This study aims to explore the habitat preference of ungulates and their relation with associated predators in the Bardia National Park, Nepal. The study was based on the transect survey and indirect observation of ungulates. Spotted deer recorded the highest density and blue bull recorded the lowest. Hog deer preferred mostly flood plains habitat and barking deer preferring mixed hardwood forest and tall grass flood plains. However, barking deer completely avoided the riverine forest and flood plain habitats. Swamp deer preferred Phata (grassland) and blue bull was recorded only in flood plains. The higher concentration of ungulates’ pellet groups were found in areas close to water sources. The study concluded that different habitat features influence the distribution and abundance of ungulates. The higher density of spotted deer and hog deer suggests these species as the major prey base to maintain viable populations of tigers in the park.
Fragmentation of the Habitat of Wild Ungulates by Anthropogenic Barriers in Mongolia  [PDF]
Takehiko Y. Ito, Badamjav Lhagvasuren, Atsushi Tsunekawa, Masato Shinoda, Seiki Takatsuki, Bayarbaatar Buuveibaatar, Buyanaa Chimeddorj
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0056995
Abstract: Habitat loss and habitat fragmentation caused by anthropogenic activities are the main factors that constrain long-distance movement of ungulates. Mongolian gazelles (Procapra gutturosa) and Asiatic wild asses (Equus hemionus) in Mongolia are facing habitat fragmentation and loss. To better understand how their movements respond to potential anthropogenic and natural barriers, we tracked 24 Mongolian gazelles and 12 wild asses near the Ulaanbaatar–Beijing Railroad and the fenced international border between Mongolia and China between 2002 and 2012. None of the tracked gazelles crossed the railroad, even though gazelles were captured on both sides of the tracks at the start of the study. Similarly, we did not observe cross-border movements between Mongolia and China for either species, even though some animals used areas adjacent to the border. The both species used close areas to the anthropogenic barriers more frequently during winter than summer. These results suggest strong impacts by the artificial barriers. The construction of new railroads and roads to permit mining and other resource development therefore creates the threat of further habitat fragmentation, because the planned routes will divide the remaining non-fragmented habitats of the ungulates into smaller pieces. To conserve long-distance movement of the ungulates in this area, it will be necessary to remove or mitigate the barrier effects of the existing and planned roads and railroads and to adopt a landscape-level approach to allow access by ungulates to wide ranges throughout their distribution.
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