| g-band patterns, hemoglobin, and transferrin types of the bharal: chromosomal evolutionary relationships with sheep and goats. | g-band patterns of the bharal (pseudois nayaur), 2n = 54, were compared with those of wild sheep (ovis dalli stonei), 2n = 54, and the persian wild goat (capra hircus), 2n = 60. patterns of the longer segments of the biarmed chromosomes of pseudois were similar to those of the longer biarmed segments of ovis, whereas the shorter segments differed. biarmed chromosomal segments had g-band homologies with specific acrocentric autosomes of capra and were ranked as follows in descending order of rela ... | 1978 | 744872 |
| fatty acid composition of dall sheep bone marrow. | | 1975 | 1122742 |
| cranial asymmetry in a dall sheep ram (ovis dalli dalli). | the horns of a 13-yr-old dall sheep ram (ovis dalli dalli) from the sheep mountain herd in kluane national park (yukon, canada) had unique characteristics. the right horn was 1,127 mm long, while the left horn was only 861 mm long and compressed and distorted at its base. the reduced growth of the left horn was due to chronic epidermitis and osteomyelitis of the cornual process, which began when the ram was 5 yr of age. | 1992 | 1602592 |
| failure to maintain interspecific pregnancy after transfer of dall's sheep embryos to domestic ewes. | over a 3-year period, 32 dall's sheep (ovis dalli dalli) embryos were transferred into 24 domestic sheep (o. aries) recipients and 4 were transferred into 2 dall's sheep recipients. in the first year, none of the 10 o. aries recipients was diagnosed pregnant. in the following 2 years, 9 (37%) of the domestic sheep recipients were pregnant on day 18, 8 (33%) on day 40, 6 (25%) on day 90 and 4 (16%) on day 120; 1 aborted at day 125 and another at day 145. pregnancies were established only in ewes ... | 1990 | 2250237 |
| acute monensin toxicosis in stone sheep (ovis dalli stonei), blesbok (damaliscus dorcus phillipsi), and a bactrian camel (camelus bactrianus). | accidental monensin toxicosis developed in 5 stone sheep (ovis dalli stonei), 5 blesbok (damaliscus dorcas phillipsi), and a bactrian camel (camelus bactrianus) at the st louis zoological park. eight animals died acutely and 1 was euthanatized because of chronic hind limb paresis. all affected animals had clinicopathologic evidence of severe muscle necrosis, serum electrolyte disturbances, and hemoconcentration. | 1990 | 2295548 |
| the distribution of wearout over evolved reliability structures. | a multiple-integral equation, termed the wearout equation, describes the distribution of wearout (or aging) over evolved reliability structures, such as organisms and self-replicating machines, and thus statistically governs virtually all aging properties of the systems. the equation is applied to the computation of ab initio ("from the beginning") life tables for four natural populations of ungulates--wild boar, dall sheep, african buffalo, and hippopotamus--which represent a broad range of sur ... | 1989 | 2779258 |
| serologic survey for mycoplasma ovipneumoniae in free-ranging dall sheep (ovis dalli) in alaska. | indirect hemagglutination tests on sera from 251 dall sheep (ovis dalli) from interior alaska collected during the period 1979 to 1987 revealed no evidence of exposure to mycoplasma ovipneumoniae. apparently, this potentially fatal disease agent has not been introduced into free-ranging dall sheep populations. in the interest of continued health of such dall sheep, strict enforcement of domestic animal health regulations and prudent land use practices are clearly indicated. | 1989 | 2810563 |
| comparison of contagious ecthyma virus genomes by restriction endonucleases. | restriction enzyme analysis with kpni revealed heterogeneity among 10 different strains of contagious ecthyma virus from sheep, musk ox, dall sheep and humans. hybridization of electroblots indicated deletion of dna segments and changes in nucleotide sequences. | 1985 | 2986582 |
| an epizootic of mycoplasma ovipneumoniae infection in captive dall's sheep (ovis dalli dalli). | in late spring of 1986, 10 of 23 dall's sheep (ovis dalli dalli) at the metropolitan toronto zoo were moved to a new exhibit, where all developed severe respiratory signs refractory to anthelmintic and antibiotic therapy. in july, two animals died with chronic active bronch-pneumonia, and a third was euthanized because of pneumonia several months later. bacteria were not isolated from the lungs of the first, steptococci and pasteurella hemolytica were isolated from the other two, respectively; m ... | 1988 | 3193557 |
| a set of test life tables for theoretical gerontology. | prediction of life tables, which provide the most empirical information available about the statistical properties of aging, provides a rigorous test for any theory of aging as manifested at the organismic level of biological organization. for this purpose, a set of test tables for the wild boar (sus scrofa), domestic sheep (ovis aries), dall sheep (ovis dalli dalli), african buffalo (syncerus cafer), and hippopotamus (hippopotamus amphibius) is reconstructed from primary data taken from the lit ... | 1988 | 3346518 |
| attempted reactivation of contagious ecthyma in dall sheep. | dexamethasone was administered to 2 dall ewes that had clinically recovered from contagious ecthyma in an attempt to reactivate contagious ecthyma in the sheep. clinical signs of disease were not detected within 24 days after corticosteroid injection, and virus was not detected in tissues collected at necropsy. | 1985 | 4037507 |
| rumen ciliate fauna of alaskan moose (alces americana), musk-ox (ovibos moschatus) and dall moutain sheep (ovis dalli). | | 1974 | 4206407 |
| eimeria dalli sp. n. (protozoa: eimeriidae) from dall sheep ovis dalli. | | 1974 | 4838471 |
| the transferrins and hemoglobins of bighorn sheep (ovis canadensis), dall sheep (ovis dalli) and mouflon (ovis musimon). | | 1971 | 5120310 |
| chromosomes of the dall sheep, ovis dalli dalli (nelson). | | 1971 | 5581380 |
| serum protein electrophoresis of coreamnos americanus (mountain goat) and comparison of sera from canadian and alaskan alces alces (moose) and ovis dalli (sheep). | | 1968 | 5758870 |
| electrophoresis of the serum proteins and transferrins of alces alces (elk), rangifer tarandus (reindeer), and ovis dalli (dall sheep) from north america. | | 1967 | 6075156 |
| serologic survey for selected microbial pathogens in alaskan wildlife. | antibodies to brucella spp. were detected in sera of seven of 67 (10%) caribou (rangifer tarandus), one of 39 (3%) moose (alces alces), and six of 122 (5%) grizzly bears (ursus arctos). antibodies to leptospira spp. were found in sera of one of 61 (2%) caribou, one of 37 (3%) moose, six of 122 (5%) grizzly bears, and one of 28 (4%) black bears (ursus americanus). antibodies to contagious ecthyma virus were detected in sera of seven of 17 (41%) dall sheep (ovis dalli) and five of 53 (10%) caribou ... | 1983 | 6139490 |
| serologic and experimental investigations of contagious ecthyma in alaska. | serologic evidence of contagious ecthyma (ce) was found in domestic sheep (ovis aries), domestic goats (capra hircus), dall sheep (ovis dalli), and musk-ox (ovibos moschatus) in alaska. a moose (alces alces) calf and a caribou (rangifer tarandus) fawn were susceptible to experimental infection and both developed antibody titers as a result. ce virus was isolated from lesions of dall sheep which were involved in a natural outbreak of the disease. | 1983 | 6644914 |
| serologic evidence of arbovirus infections in humans and wild animals in alaska. | blood samples were collected from humans and several species of free-ranging wild animals in alaska. sera were tested for antibody to jamestown canyon (jc), snowshoe hare (ssh), northway (nor), klamath (kla), sakhalin (sak), great island (gi), and silverwater (sil) virus. jc antibody was found in 54% of 121 human, 89% of 97 bison (bison bison), 51% of 84 dall sheep (ovis dalli), 43% of 68 snowshoe hare (lepus americanus), and 3% of 33 arctic fox (alopex lagopus) sera. ssh antibody was found in 4 ... | 1983 | 6644915 |
| further studies on horn aberrations in dall's sheep (ovis dalli dalli) from yukon territory, canada. | the prevalence of horn aberrations in dall's sheep from the kluane lake area of yukon territory observed during july 1982 represented 1% of the total population and 7% of rams 6 yr or older. ewes were not considered in these percentages because they were too difficult to inspect by aerial survey. when these data were combined with other data collected from 1977 through 1981, the prevalence equalled 2.4% of the total population and slightly exceeded 16% in mature rams (greater than or equal to 6 ... | 1984 | 6737607 |
| upper canines in dall's sheep (ovis dalli dalli). | | 1984 | 6737613 |
| hematologic, serum chemistry and serologic values of dall's sheep (ovis dalli dalli) in alaska. | in june 1979, 73 dall's sheep were captured near tok, alaska to determine selected hematologic and serum metabolite parameters and to determine the presence of antibodies to selected pathogens. hematology and serum metabolite values were compared with values for domestic sheep and bighorn sheep (ovis canadensis). antibodies were detected against brucella sp. (4%), campylobacter feti (30%), contagious ecthyma virus (23%) and bovine parainfluenza type 3 virus (1%). antibodies were not detected aga ... | 1983 | 6887435 |
| contagious ecthyma in an adult dall sheep (ovis dalli dalli) in alaska. | | 1982 | 7097867 |
| horn aberrations in dall's sheep (ovis dalli) from yukon territory, canada. | horn aberrations in dall's sheep from the kluane lake area of yukon territory were of two basic types. in the more prevalent type, the horn was severed at an annual growth check and the terminal segment of the remaining portion formed a short conical protuberance. the second type had characteristics of the first, but in addition, underwent extreme twisting or torquing during subsequent growth. sheep with aberrant horns represented 2% of the kluane lake population or 14% of harvestable rams (grea ... | 1982 | 7131653 |
| aberrations of the tooth arcade and mandible in dall's sheep from southwestern yukon. | nine dall's sheep (ovis dalli dalli) collected in the ruby mountains of southwestern yukon were examined for aberrations of the tooth arcade and mandible. missing and displaced teeth were common in older sheep (greater than or equal to 6 yr). necrosis of the mandible was observed in five of eight rams and in one ewe. corynebacterium pyogenes was cultured from exudates from two rams with enlarged fistulated mandibles. the sequence of events leading to lesions of the tooth arcade and to "lumpy jaw ... | 1982 | 7131654 |
| secondary amyloidosis in dall's sheep. | | 1982 | 7131665 |
| contagious ecthyma in alaskan musk-oxen and dall sheep. | in 1976 and 1977, a disease resembling contagious ecthyma was seen in captive musk-oxen (ovibos moschatus) in alaska. a similar disease occurred in 1977 in captive dall sheep (ovis dalli). paravaccinia viruses were detected by electron microscopy and isolated in cell cultures from both species. experimental inoculation in susceptible and immune domestic sheep (ovis aries) plus fluorescent antibody tests with ecthyma-immune conjugate indicated that the isolate was contagious ecthyma virus. | 1981 | 7327995 |
| factors controlling lambing period of dall's sheep. | | 1980 | 7427797 |
| comparative aspects of biochemical polymorphism in the blood of caprinae species and their hybrids. | biochemical variation at 14 blood loci was reviewed, and specific features compared experimentally in sheep ovis aries, mouflon ovis musimon, goat capra hircus, aoudad ammotragus iervia and in 2 stillborn aoudad x goat hybrids. variation at 3 loci was also studied in dall sheep ovis dalli, bighorn sheep ovis canadensis and rocky mountain goat oreamnos americanus. haemoglobin c production in an anaemic hb ab mouflon and in mouflon x sheep hybrids was examined. mouflon differ from domestic sheep i ... | 1980 | 7458003 |
| contact transmission of psoroptic mange from bighorn to stone sheep. | psoroptes sp. mites and tan crusty lesions were detected in the ears of a captive stone sheep (ovis dalli stonei) in april 1996, after contact with infected captive rocky mountain bighorn sheep (ovis canadensis canadensis). psoroptes spp. have not been detected in free-ranging ungulates in canada or alaska (usa). this is the first report of psoroptes sp. in stone sheep, indicating their susceptibility to infection. | 1997 | 9249721 |
| susceptibility of dall sheep (ovis dalli dalli) to pneumonia caused by pasteurella haemolytica. | we evaluated susceptibility of dall sheep (ovis dalli dalli) to bacterial pneumonia induced by two strains of pasteurella haemolytica of domestic sheep origin by evaluating the sensitivity of blood neutrophils of eight dall sheep to lysis by cytotoxins of p. haemolytica, and by intratracheal inoculation of three dall sheep, two bighorn sheep (ovis canadensis), and two domestic sheep with 3.7 x 10(6) or 2.5 x 10(7) colony forming units of p. haemolytica. neutrophils from the dall sheep were more ... | 1996 | 9359056 |
| antibody responses to psoroptes sp. mites in dall sheep (ovis dalli). | we determined that antibody responses to psoroptes sp. mites were not present in 403 of 407 sera samples collected opportunistically from 1979 through 1991 from dall sheep (ovis dalli) from five locations in alaska, usa (eastern arctic, n = 61; central arctic, n = 15; western interior, n = 122; central interior, n = 63; eastern interior, n = 146). test values for four samples exceeded the positive cutoff value for the immunoassay, but exposure to mites could not be confirmed since the 95% confid ... | 1996 | 9359078 |
| biovariants of isolates of pasteurella from domestic and wild ruminants. | a total of 608 bacterial isolates previously identified as pasteurella haemolytica biotypes a and 3, p. trehalosi, and p. multocida, were separated into 73 distinct biovariants using 21 phenotypic characteristics. the largest group (54%) of wildlife isolates was identified as biogroup 2 and biogroup 2 variants. biogroup 2 and biogroup 2 variants accounted for only 17% of isolates from domestic ruminants and were all from sheep. in contrast, 43% of isolates from domestic ruminants were identified ... | 1998 | 9526860 |
| serologic survey for toxoplasma gondii in selected wildlife species from alaska. | blood was collected from selected wildlife species in specific areas of alaska (usa) during 1976-96. a modified agglutination test was used to test sera for evidence of exposure to toxoplasma gondii. serum antibody prevalence was 43% (62 positive of 143 tested) for black bears (ursus americanus), 9% (11/125) for wolves (canis lupus), 7% (22/319) for dall sheep (ovis dalli), 6% (14/241) for caribou (rangifer tarandus), 1% (3/240) for moose (alces alces), and 1% (2/241) for bison (bison bison). a ... | 2000 | 10813602 |
| lumpy jaw in wild sheep and its evolutionary implications. | the distribution and prevalence of mandibular osteomyelitis, lumpy jaw, and other dental anomalies in wild sheep were investigated and their biological and evolutionary implications were assessed. our survey was based on 3,363 mandibles of wild sheep and 1,028 from domesticated varieties. lumpy jaw is widespread in wild sheep of north america, but it is rare or absent in wild sheep from eurasia. among the subspecies of ovis spp. in north american, the thinhorn sheep (ovis dalli) were the most se ... | 2001 | 11272503 |
| new host and geographic records for two protostrongylids in dall's sheep. | biodiversity survey and inventory have resulted in new information on the distribution of protostrongylidae in dall's sheep (ovis dalli dalli) from the northwest territories (nt, canada) and from alaska (ak, usa). in 1998, parelaphostrongylus odocoilei adults were found for the first time in the skeletal muscles of dall's sheep in the mackenzie mountains (nt). adult p. odocoilei were associated with petechial and ecchymotic hemorrhages and localized myositis; eggs and larvae in the lungs were as ... | 2001 | 11763740 |
| serum antibody prevalence of malignant catarrhal fever viruses in seven wildlife species from alaska. | blood samples were collected from seven species of free-ranging ungulates in alaska. sera were tested for evidence of exposure to malignant catarrhal fever viruses (mcfv) by means of a competitive enzyme-linked immunosorbent assay. antibody prevalences were as follows: muskox (ovibos moschatus) 100 positive samples of 104 tested (96%); dall sheep (ovis dalli) 212 of 222 (95%); elk (cervus elaphus) 14 of 51 (27%); bison (bison bison) 34 of 197 (17%); caribou (rangifer tarandus) nine of 232 (4%); ... | 2002 | 12238366 |
| population genetic structure of north american thinhorn sheep (ovis dalli). | the thinhorn sheep (ovis dalli ssp.) provides a rare example of a north american large mammal that occupies most of its native range and maintains close to ancestral population size. there are currently two recognized subspecies, dall's sheep (o. d. dalli) and stone's sheep (o. d. stonei), the validity of which remains uncertain. we investigated the spatial genetic structure of thinhorn sheep populations representing both subspecies by genotyping individuals (n = 919) from across the species ran ... | 2004 | 15315669 |
| muskox lungworm (umingmakstrongylus pallikuukensis) does not establish in experimentally exposed thinhorn sheep (ovis dalli). | muskoxen (ovibos moschlatus moschatus) on the northwestern mainland of nunavut and northwest territories, canada, are infected with the protostrongylid lungworm, umingmaksrongylus pallikuuhkensis. the geographic range of this muskox population is expanding to the south and west, and it is anticipated that these animals will eventually become sympatric with dall's sheep (ovis dalli dalli) in the mackenzie and richardson mountains. to address the concern of wildlife managers that u. pallikulkensis ... | 2004 | 15362818 |
| geographic distribution of the muscle-dwelling nematode parelaphostrongylus odocoilei in north america, using molecular identification of first-stage larvae. | molecular identification of dorsal-spined larvae (dsl) from fecal samples indicates that the protostrongylid parasite parelaphostrongylus odocoilei occupies a broader geographic range in western north america than has been previously reported. we analyzed 2,124 fecal samples at 29 locations from thinhorn sheep (ovis dalli dalli and o. d. stonei), bighorn sheep (ovis canadensis canadensis and o. c. californiana), mountain goats (oreamnos americanus), woodland caribou (rangifer tarandus caribou), ... | 2005 | 16108550 |
| phylogenetic analysis of snow sheep (ovis nivicola) and closely related taxa. | based on mitochondrial cytochrome b gene sequence analysis, the history of true sheep (ovis) began approximately 3.12 million years ago (mya). the evolution of ovis resulted in three generally accepted genetic groups: argaliforms, moufloniforms, and pachyceriforms. the pachyceriforms of the subgenus pachyceros comprise the thin-horn sheep ovis nivicola (snow sheep), ovis dalli (dall and stone sheep), and ovis canadensis (rocky mountain and desert bighorn). north america wild sheep (o. canadensis ... | 2006 | 16267166 |
| climate change and the epidemiology of protostrongylid nematodes in northern ecosystems: parelaphostrongylus odocoilei and protostrongylus stilesi in dall's sheep ( ovis d. dalli ). | we describe the epidemiology of the protostrongylid parasites parelaphostrongylus odocoilei and protostrongylus stilesi in dall's sheep (ovis dalli dalli) from the mackenzie mountains, northwest territories, canada (65 degrees n; 128 degrees w). peak numbers of 1st-stage larvae of both parasites were shed by dall's sheep on their winter range from march until may. in larval development experiments in the mackenzie mountains, peak numbers of infective 3rd-stage larvae of p. odocoilei were availab ... | 2006 | 16332289 |
| development and pathogenesis of parelaphostrongylus odocoilei (nematoda: protostrongylidae) in experimentally infected thinhorn sheep (ovis dalli ). | recently, the protostrongylid nematode parelaphostrongylus odocoilei has been reported in a new host species, thinhorn sheep (ovis dalli). for the first time, we completed the life cycle of p. odocoilei in three stone's sheep (o. dalli stonei) and two thinhorn hybrids (o. dalli stonei x o. dalli dalli), each infected with 200 third-stage larvae from slugs (deroceras laeve). the prepatent period ranged from 68 days to 74 days, and shedding of first-stage larvae (l1) peaked at >10,000 l1 per gram ... | 2005 | 16456155 |
| detecting the signature of selection on immune genes in highly structured populations of wild sheep (ovis dalli). | the confounding effects of population structure complicate efforts to identify regions of the genome under the influence of selection in natural populations. here we test for evidence of selection in three genes involved in vertebrate immune function - the major histocompatibility complex (mhc), interferon gamma (ifng) and natural resistance associated macrophage polymorphism (nramp) - in highly structured populations of wild thinhorn sheep (ovis dalli). we examined patterns of variation at micr ... | 2006 | 16499690 |
| caudal polymorphism and cephalic morphology among first-stage larvae of parelaphostrongylus odocoilei (protostrongylidae: elaphostrongylinae) in dall's sheep from the mackenzie mountains, canada. | we demonstrate polymorphism in the structure of the tail among first-stage larvae of parelaphostrongylus odocoilei (protostrongylidae). two distinct larvae, both with a characteristic dorsal spine, include (1) a morphotype with a kinked conical tail marked by 3 distinct transverse folds or joints and a symmetrical terminal tail spike and (2) a morphotype with a digitate terminal region lacking folds or joints and with an asymmetrical, subterminal tail spike. these divergent larval forms had been ... | 2005 | 16539011 |
| phylogenetic diversity of pasteurellaceae and horizontal gene transfer of leukotoxin in wild and domestic sheep. | wild and domestic animal populations are known to be sources and reservoirs of emerging diseases. there is also a growing recognition that horizontal genetic transfer (hgt) plays an important role in bacterial pathogenesis. we used molecular phylogenetic methods to assess diversity and cross-transmission rates of pasteurellaceae bacteria in populations of bighorn sheep, dall's sheep, domestic sheep and domestic goats. members of the pasteurellaceae cause an array of deadly illnesses including ba ... | 2007 | 16635591 |
| the serologic prevalence of q fever (coxiella burnetii) complement-fixing antibodies in the peninsular bighorn sheep of southern california. | q fever is a rare illness in the southern california desert. during the past 34 years only 6 patients have been diagnosed with the disease at the eisenhower medical center, a referral center for much of the desert and surrounding mountains. in all but 2 instances, q fever was identified in patients who have been in contact with imported domestic sheep who are brought to the desert to graze and lamb in the fall and winter. the sheep are sent back to idaho, wyoming, and montana in the spring. with ... | 2006 | 16896140 |
| globally dispersed y chromosomal haplotypes in wild and domestic sheep. | to date, investigations of genetic diversity and the origins of domestication in sheep have utilised autosomal microsatellites and variation in the mitochondrial genome. we present the first analysis of both domestic and wild sheep using genetic markers residing on the ovine y chromosome. analysis of a single nucleotide polymorphism (oy1) in the sry promoter region revealed that allele a-oy1 was present in all wild bighorn sheep (ovis canadensis), two subspecies of thinhorn sheep (ovis dalli), e ... | 2006 | 16978172 |
| horn growth rate and longevity: implications for natural and artificial selection in thinhorn sheep (ovis dalli). | we used horn measurements from natural and hunted mortalities of male thinhorn sheep ovis dalli from yukon territory, canada, to examine the relationship between rapid growth early in life and longevity. we found that rapid growth was associated with reduced longevity for sheep aged 5 years and older for both the hunted and natural mortality data sets. the negative relationship between growth rate and longevity in hunted sheep can at least partially be explained by morphologically biased hunting ... | 2007 | 17305848 |
| protostrongylid parasites and pneumonia in captive and wild thinhorn sheep (ovis dalli). | we describe health significance of protostrongylid parasites (parelaphostrongylus odocoilei and protostrongylus stilesi) and other respiratory pathogens in more than 50 naturally infected dall's sheep (ovis dalli dalli) from the mackenzie mountains, northwest territories (1998-2002) as well as in three stone's sheep (o. d. stonei) experimentally infected with p. odocoilei (2000-2002). histological lesions in the brain and distribution of p. odocoilei in the muscles of experimentally and naturall ... | 2007 | 17495303 |
| bilateral perirenal hemorrhage in two stone's sheep (ovis dalli stonei): a possible manifestation of malignant catarrhal fever. | malignant catarrhal fever (mcf)-like disease was diagnosed at postmortem in 2 stone's sheep (ovis dalli stonei). on gross examination, the predominant abnormality in both sheep was severe perirenal hemorrhage and multiple renal infarcts. microscopically, there was severe, multisystemic lymphocytic arteritis. both sheep were positive for ovine herpesvirus 2 (ovhv-2) on polymerase chain reaction, and partial sequencing of the viral dna polymerase genes from the 2 sheep revealed >99% homology, with ... | 2008 | 18776110 |
| re-sequencing regions of the ovine y chromosome in domestic and wild sheep reveals novel paternal haplotypes. | the male-specific region of the ovine y chromosome (msy) remains poorly characterized, yet sequence variants from this region have the potential to reveal the wild progenitor of domestic sheep or examples of domestic and wild paternal introgression. the 5' promoter region of the sex-determining gene sry was re-sequenced using a subset of wild sheep including bighorn (ovis canadensis), thinhorn (ovis dalli spp.), urial (ovis vignei), argali (ovis ammon), mouflon (ovis musimon) and domestic sheep ... | 2009 | 19016675 |
| the role of phenotypic plasticity in responses of hunted thinhorn sheep ram horn growth to changing climate conditions. | when phenotypic change occurs over time in wildlife populations, it can be difficult to determine to what degree it is because of genetic effects or phenotypic plasticity. here, we assess phenotypic changes over time in horn length and volume of thinhorn sheep (ovis dalli) rams from yukon territory, canada. we considered 42 years of horn growth from over 50,000 growth measurements in over 8000 individuals. we found that weather explained a large proportion of the annual fluctuation in horn growt ... | 2010 | 20163506 |
| a genome-wide set of snps detects population substructure and long range linkage disequilibrium in wild sheep. | the development of genomic resources for wild species is still in its infancy. however, cross-species utilization of technologies developed for their domestic counterparts has the potential to unlock the genomes of organisms that currently lack genomic resources. here, we apply the ovinesnp50 beadchip, developed for domestic sheep, to two related wild ungulate species: the bighorn sheep (ovis canadensis) and the thinhorn sheep (ovis dalli). over 95% of the domestic sheep markers were successfull ... | 2011 | 21429138 |
| "emerging" parasitic infections in arctic ungulates. | important drivers for emergence of infectious disease in wildlife include changes in the environment, shrinking habitats or concentration of wildlife, and movement of people, animals, pathogens, or vectors. in this paper we present three case-studies of emerging parasitic infections and diseases in ungulates in the canadian north. first we discuss climate warming as an important driver for the emergence of disease associated with umingmakstrongylus pallikuukensis, a nematode lungworm of muskoxen ... | 2004 | 21680491 |
| cadmium and other elements in tissues from four ungulate species from the mackenzie mountain region of the northwest territories, canada. | tissue samples from four ungulate species from the south mackenzie mountain region of the northwest territories (nt), canada, were analysed for stable and radioactive elements and (15)n and (13)c stable isotopes. elevated cd concentrations in moose (alces americanus) kidney have been observed in the region and are a health care concern for consumers of traditional foods. this study examined the factors associated with, and potential renal effects from, the accumulation of cadmium, and interactio ... | 2016 | 27240258 |
| parasites in ungulates of arctic north america and greenland: a view of contemporary diversity, ecology, and impact in a world under change. | parasites play an important role in the structure and function of arctic ecosystems, systems that are currently experiencing an unprecedented rate of change due to various anthropogenic perturbations, including climate change. ungulates such as muskoxen, caribou, moose and dall's sheep are also important components of northern ecosystems and are a source of food and income, as well as a focus for maintenance of cultural traditions, for northerners. parasites of ungulates can influence host healt ... | 2012 | 22726643 |
| immunocontraception of captive exotic species: v. prolonged antibody titers in dall sheep (ovis dalli dalli) and domestic goats (capra hircus) immunized with porcine zona pellucida. | native porcine zona pellucida (pzp) immunocontraception has been used to inhibit fertility in more than 80 species of ungulates, although the duration of contraception efficacy varies among species in both perissodactyla and artiodactyla. this study examined anti-pzp antibody titers in dall sheep and domestic goats at the milwaukee county zoo, and also himalayan tahr and armenian mouflon sheep at the san diego zoo safari park, and, for comparison, altai wapiti, lowland wisent, javan banteng, and ... | 2013 | 24437081 |
| beta-globin gene evolution in the ruminants: evidence for an ancient origin of sheep haplotype b. | domestic sheep (ovis aries) can be divided into two groups with significantly different responses to hypoxic environments, determined by two allelic beta-globin haplotypes. haplotype a is very similar to the goat beta-globin locus, whereas haplotype b has a deletion spanning four globin genes, including beta-c globin, which encodes a globin with high oxygen affinity. we surveyed the beta-globin locus using resequencing data from 70 domestic sheep from 42 worldwide breeds and three ovis canadensi ... | 2015 | 26096044 |
| snp discovery in candidate adaptive genes using exon capture in a free-ranging alpine ungulate. | identification of genes underlying genomic signatures of natural selection is key to understanding adaptation to local conditions. we used targeted resequencing to identify snp markers in 5321 candidate adaptive genes associated with known immunological, metabolic and growth functions in ovids and other ungulates. we selectively targeted 8161 exons in protein-coding and nearby 5' and 3' untranslated regions of chosen candidate genes. targeted sequences were taken from bighorn sheep (ovis canaden ... | 2016 | 27327375 |
| genome-wide set of snps reveals evidence for two glacial refugia and admixture from postglacial recolonization in an alpine ungulate. | past glaciation events have played a major role in shaping the genetic diversity and distribution of wild sheep in north america. the advancement of glaciers can isolate populations in ice-free refugia, where they can survive until the recession of ice sheets. the major beringian refugium is thought to have held thinhorn sheep (ovis dalli) populations during times of glacial advance. while isolation in the major refugium can account for much of the genetic and morphological diversity seen in ext ... | 2016 | 27272944 |
| the complete mitochondrial genome sequence analysis of tibetan argali (ovis ammon hodgsoni): implications of tibetan argali and gansu argali as the same subspecies. | the genus ovis (bovidae, artiodactyla) includes six species, i.e. ovis ammon, ovis aries, ovis canadensis, ovis dalli, ovis nivicola and ovis vignei. based on morphology, geographical location, habitat, etc., the species o. ammon is divided into nine subspecies. the near threatened tibetan argali is distributed across the tibetan plateau and its peripheral mountains, and believed to be one of the o. ammon subspecies (o. a. hodgsoni). however, considering its morphological features and distributi ... | 2013 | 23542075 |
| identification of landscape features influencing gene flow: how useful are habitat selection models? | understanding how dispersal patterns are influenced by landscape heterogeneity is critical for modeling species connectivity. resource selection function (rsf) models are increasingly used in landscape genetics approaches. however, because the ecological factors that drive habitat selection may be different from those influencing dispersal and gene flow, it is important to consider explicit assumptions and spatial scales of measurement. we calculated pairwise genetic distance among 301 dall's sh ... | 2016 | 27330556 |
| changes in horn size of stone's sheep over four decades correlate with trophy hunting pressure. | selective harvest may lead to rapid evolutionary change. for large herbivores, trophy hunting removes males with large horns. that artificial selection, operating in opposition to sexual selection, can lead to undesirable consequences for management and conservation. there have been no comparisons of long-term changes in trophy size under contrasting harvest pressures. we analyzed horn measurements of stone's rams (ovis dalli stonei) harvested over 37 years in two large regions of british columb ... | 2016 | 27039527 |
| shrubline but not treeline advance matches climate velocity in montane ecosystems of south-central alaska. | tall shrubs and trees are advancing into many tundra and wetland ecosystems but at a rate that often falls short of that predicted due to climate change. for forest, tall shrub, and tundra ecosystems in two pristine mountain ranges of alaska, we apply a bayesian, error-propagated calculation of expected elevational rise (climate velocity), observed rise (biotic velocity), and their difference (biotic inertia). we show a sensitive dependence of climate velocity on lapse rate and derive biotic vel ... | 2016 | 26719133 |
| pleistocene glaciations, fluctuating ranges, and low genetic variability in a large mammal (ovis dalli). | | 1986 | 28556217 |
| notes on populations of bovicola jellisoni on dall's sheep ( ovis dalli ). | this paper reports the first record of a mallophagan species on the dall's sheep ( ovis dalli ). the numbers and distribution of bovicola jellisoni on two dall's sheep collected on crescent mountain, kenai peninsula, alasaka, is described. | 1977 | 24228966 |
| orf virus infection in alaskan mountain goats, dall's sheep, muskoxen, caribou and sitka black-tailed deer. | the zoonotic orf virus (orfv; genus parapoxvirus, poxviridae family) occurs worldwide and is transmitted between sheep and goats, wildlife and man. archived tissue samples from 16 alaskan wildlife cases, representing mountain goat (oreamnos americanus, n = 8), dall's sheep (ovis dalli dalli, n = 3), muskox (ovibos moschatus, n = 3), sitka black-tailed deer (odocoileus hemionus sitkensis, n = 1) and caribou (rangifer tarandus granti, n = 1), were analyzed. | 2018 | 29467004 |
| predation risk and space use of a declining dall sheep (ovis dalli dalli) population. | the abundance of ungulate populations may fluctuate in response to several limiting factors, including climate, diseases, and predation. in the northern richardson mountains, canada, dall sheep (ovis dalli dalli) have undergone a major decline in the past decades and predation by grizzly bears (ursus arctos) and wolves (canis lupus) was suspected as a leading cause. to better understand the relationship between these three species located in this rugged and remote ecosystem, we relied on a combi ... | 2019 | 30986250 |
| parasite intensity drives fetal development and sex allocation in a wild ungulate. | an understanding of the mechanisms influencing prenatal characteristics is fundamental to comprehend the role of ecological and evolutionary processes behind survival and reproductive success in animals. although the negative influence of parasites on host fitness is undisputable, we know very little about how parasitic infection in reproductive females might influence prenatal factors such as fetal development and sex allocation. using an archival collection of dall's sheep (ovis dalli dalli), ... | 2020 | 32973197 |
| phenotypic plasticity and local adaptation in freeze tolerance: implications for parasite dynamics in a changing world. | marshallagia marshalli is a multi-host gastrointestinal nematode that infects a variety of artiodactyl species from temperate to arctic latitudes. eggs of marshallagia are passed in host faeces and develop through three larval stages (l1, l2, and l3) in the environment. although eggs normally hatch as l1s, they can also hatch as l3s. we hypothesised that this phenotypic plasticity in hatching behaviour may improve fitness in subzero and highly variable environments, and this may constitute an ev ... | 2020 | 32004511 |
| navigating snowscapes: scale-dependent responses of mountain sheep to snowpack properties. | winters are limiting for many terrestrial animals due to energy deficits brought on by resource scarcity and the increased metabolic costs of thermoregulation and traveling through snow. a better understanding of how animals respond to snow conditions is needed to predict the impacts of climate change on wildlife. we compared the performance of remotely sensed and modeled snow products as predictors of winter movements at multiple spatial and temporal scales using a data set of 20,544 locations ... | 2018 | 30074675 |
| diversity of gastrointestinal helminths in dall's sheep and the negative association of the abomasal nematode, marshallagia marshalli, with fitness indicators. | gastrointestinal helminths can have a detrimental effect on the fitness of wild ungulates. arctic and subarctic ecosystems are ideal for the study of host-parasite interactions due to the comparatively simple ecological interactions and limited confounding factors. we used a unique dataset assembled in the early seventies to study the diversity of gastrointestinal helminths and their effect on fitness indicators of dall's sheep, ovis dalli dalli, in the mackenzie mountains, northwest territories ... | 2018 | 29538393 |
| investigating relationships between reproduction, immune defenses, and cortisol in dall sheep. | life-history theory is fundamental to understanding how animals allocate resources among survival, development, and reproduction, and among traits within these categories. immediate trade-offs occur within a short span of time and, therefore, are more easily detected. trade-offs, however, can also manifest across stages of the life cycle, a phenomenon known as carryover effects. we investigated trade-offs on both time scales in two populations of dall sheep (ovis dalli dalli) in southcentral ala ... | 2018 | 29445376 |