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1.
Twenty-six free-ranging North American bison (Bison bison) (22 adult bulls, one yearling male and three adult females) were immobilized using a combination of carfentanil and xylazine. For carfentanil the dose range (mean +/- SD) was 1.8-5.0 micrograms/kg (2.4 +/- 0.7 micrograms/kg) and for xylazine 0.004-0.125 mg/kg (0.07 +/- 0.03 mg/kg). Induction time (mean +/- SE) was 14.2 +/- 2.9 min (median 8 min), while the total mean reversal time after administration of a narcotic antagonist was 9.0 +/- 1.4 min (median 8 min). Only one animal that received the highest initial dose of carfentanil (2.5 mg) showed evidence of becoming "re-narcotized." Five animals required two or more doses of carfentanil before becoming immobilized. Overall, small volumes of drug used (mean = 0.62 ml for carfentanil, 0.53 ml for xylazine) enabled the use of 1 to 2 ml darts, increasing both accuracy and impact safety. Darting success approached 100%.  相似文献   

2.
Seed dispersal is a crucial process for the dynamics and maintenance of plant populations. Free-ranging animals are effective dispersal vectors because they can move between similar habitats and transport seeds into favourable environments. Dung samples from two species of common free-ranging mammals—deer and wild boar—were used to study endozoochorous dispersal of seeds in a military training area in western Bohemia. The area was abandoned after WWII, and the military training area was established in 1953. The vegetation consists of shrublands and dry grasslands. Data on the local species pool of grassland herbs and forbs were collected to compare the characteristics of dispersed versus non-dispersed plants. Deer and wild boar dispersed 84 plant species; however, species composition of seedlings emerging from dung samples showed significant differences between dispersal vectors and notable change across the growing season. 80% of all seedlings extracted from the dung samples belonged to stinging nettle, Urtica dioica. From trait analyses, seeds of endozoochorous plants had a higher longevity index in the soil seed bank than non-endozoochorous plants and more often possessed a mucilaginous surface. Our results show that deer and boar are successful, though not substitutable dispersers.  相似文献   

3.
Sarcocysts of Sarcocystis sp. were found in the striated muscles from 11 of 14 wild Florida panthers (Felis concolor coryi) and four of four cougars (two wild F. concolor stanleyana and two captive F. concolor of undetermined subspecies). The common occurrence of sarcocysts in muscles of top carnivores such panthers and cougars is unexplained. This stage of the life cycle is normally confined to the muscles of the prey species. Because large felids are rarely preyed upon, it is unlikely that a species of Sarcocystis has evolved using large cats as intermediate hosts. Therefore, the presence of these sarcocysts might be an indication of immune compromise in these felids, enabling the atypical development of the sarcocysts.  相似文献   

4.
During a 13 month field study of baboons in the Gombe Stream National Park, Tanzania, the troop under observation divided into two groups. One group left the main troop to become ultimately an independent troop with a separate range. The troop fission followed a period of instability in the male status hierarchy. The events prior to and during the troop fission are described in detail and the membership of the group which left is analyzed. Social bonds prior to the fission, including kinship, determined membership in the group which left. Aggression from members of the main troop played a major role in causing the group which left to establish a new range. This fission is compared with troop fissions observed in rhesus and Japances macaques.  相似文献   

5.
A free-ranging male olive baboon (P. c. anubis) was observed as he used a small twig to locate, extract, and sort pea-sized stone fragments from a clay matrix prior to chewing and swallowing them. Occurrence of this behavior in a feral cercopithecine monkey, albeit in a single instance, indicates that the capacity for tool-use extends more broadly and deeply into the order Primates than heretofore recognized.  相似文献   

6.
While trying to achieve their nutritional requirements, foraging herbivores face the costs of plant defenses, such as toxins. Teasing apart the costs and benefits of various chemical constituents in plants is difficult because their chemical defenses and nutrient concentrations often co-vary. We used an approach derived from predator–prey studies to quantitatively compare the foraging response of a free-ranging mammalian herbivore, the swamp wallaby (Wallabia bicolor), through three feeding trials with artificial diets that differed in their concentrations of (1) the terpene 1,8-cineole, (2) primary constituents (including nitrogen and fiber), and (3) both the terpene and the primary constituents. Applying the giving-up density (GUD) framework, we demonstrated that the foraging cost of food patches increases with higher dietary cineole concentration and decreases with higher dietary nutrient concentration. The effect of combined differences in nutrients and cineole concentrations on GUD was interactive, and high nutrient food required more cineole to achieve the same patch value as low nutrient food. Our results indicate that swamp wallabies equate low nutrient, poorly defended food with high nutrient, highly defended food, providing two contrasting diets with similar cost–benefit outcomes. This behavior suggests that equal concentrations of chemical defenses provide nutrient-poor plants with relatively greater protection as nutrient-rich plants. Nutrient-rich plants may therefore face the exacerbated problem of being preferred by herbivores and therefore need to produce more defense compounds to achieve the same level of defense as nutrient-poor plants. Our findings help explain the difference in anti-herbivore strategy of nutrient-poor and rich plants, i.e., tolerance versus defense.  相似文献   

7.
Light and electron microscopic studies and feeding experiments have confirmed the presence of two species of Sarcocystis in the water buffalo Bubalus bubalis. One is the already known species with large macroscopic sarcocysts, Sarcocystis fusiformia (Railliet, 1897) Bernard and Bauche, 1912 and the other is S. levinei n. sp. which is being described in detail. The sarcocysts of S. levinei are 0.9 x 0.1 mm and the zoites in them 17.8 x 4.2 micrometer. Ultrastructurally, the primary cyst wall shows sloping villi with irregular wavy outlines. Within the villi are coarse granules and annulated fibrils. Trabeculae are present. The sexual stages of S. levinei occur in the subepithelial tissue of the small intestine of the dog and sporocysts shed by this definitive host are 15-16 by 10 micrometer.  相似文献   

8.
Re-introduced Przewalski horses in Hustai National Park, Mongolia could suffer from food competition with other herbivore species through food resource depletion. Diet composition of the Przewalski horse (Equus ferus przewalskii), red deer (Cervus elaphus) and four livestock species (sheep, goat, cattle and horse) were studied, using micro histological analysis of faecal samples in the summer of 2005 and winter of 2006 – 2007. We expected that herbivores become less selective in food choice in winter regarding to summer, resulting in a larger diet breadth, a larger similarity in diet and a larger dietary overlap in winter, potentially triggering exploitative competition by depletion of shared resources. Vegetation biomass decreased during winter, and the different herbivores species in HNP changed their diet from summer to winter. As expected diet breadth, diet similarity and dietary overlap were significantly larger in winter in comparison to summer. The existence of competition by resource depletion between the different species cannot be ruled out. Vegetation biomass was probably not a limiting factor according to the correlation between annual rainfall and herbivore species biomass, however the forage quality may be limiting, triggering competition.  相似文献   

9.
The two species of Sarcocystis--S. levinei and S. fusiformis from the water buffalo, Bubalus bubalis, show some ultrastructural similarities in their cyst wall and zoites. The zoites of both species are of about the same size, banana-shaped and have 22 subpellicular microtubules, numerous micronemes, eight rhoptries, a micropore in the region of the micronemes, an elongated mitochondrion, and a nucleus. S. levinei has 200--300 micronemes and S. fusiformis has about 400. The sarcocysts of both species are trabeculated and their cyst walls have cytophaneres containing annulated fibrils and coarse, electron dense granules. The cytophaneres of S. levinei are sloping, with irregular, wavy outlines, whereas S. fusiformis has the cauliflower-type of cytophaneres. This difference in the appearance of the cytophaneres, together with the difference in size of the sarcocysts and their definitive hosts, further confirms that S. levinei and S. fusiformis are two distinct species in the water buffalo.  相似文献   

10.
Poly(A)+ RNA was purified from cystozoites of Sarcocystis gigantea and Sarcocystis tenella and used to in vitro translate polypeptides in a wheat germ and a rabbit reticulocyte translation system. The in vitro translated polypeptides were compared by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The S. tenella mRNA translated at least two polypeptides (mol. wt about 80,000 and 21,500) in both translation systems that were not translated by the S. gigantea mRNA. To study co-translational and initial post-translational processing in Sarcocystis, the poly(A)+ RNA preparations were in vitro translated in the rabbit reticulocyte translation system in the presence or absence of canine microsomal membranes. Based on electrophoresis, there appeared to be modification of at least some Sarcocystis polypeptides in the mol. wt range 17,000-30,000. In addition, the translation products were immunoprecipitated with a homologous and a heterologous antiserum. The immunoprecipitated polypeptides were compared by electrophoresis and the S. tenella translation products contained at least one unique antigenic polypeptide with a mol. wt of about 34,700 that was not processed by the microsomal membranes. These results suggest that there is at least one polypeptide that is a candidate for use as an antigen for the differentiation of S. gigantea and S. tenella infections in sheep.  相似文献   

11.
SYNOPSIS. Cysts of Sarcocystis sp. are described from a dog. They are spherical to elongate, 110–250 μ in diameter, and contain numerous crescentic trophozoites measuring 4–5 × 1.5 μ. No septa were seen. This is the first report of Sarcocystis from a domestic carnivore.  相似文献   

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15.
A I Radchenko 《Tsitologiia》1991,33(3):95-100
An electron microscope study of sulfatized glycosaminoglycans (SG) was made for cyst stages of S. muris. The polysaccharides were detected in the submembranous and subwall layers of the sarcocysts, in addition to the ground substance and septae. Moreover SG were discovered in the cyst stages themselves--metrocytes, intermediate cells and merozoites (gamonts). SG were discernible as electron dark spots in vacuoles of the metrocytes. SG shaped as granules were scattered in the cytoplasm of both intermediate cells and merozoites. More granules of SG were seen in the cytoplasm of the merozoites compared to the intermediate cells. Thus, the quantity, localization and structure of SG are seen to follow the process of differentiation in muscle cysts of S. muris.  相似文献   

16.
The dental remains of ten adult chimpanzees from Gombe National Park, Tanzania, were examined for enamel attrition, caries, abscesses, periodontal disease, and tooth loss. Age was the underlying factor in the development of dental pathology, in that enamel wear was present to some extent in all ten but was uniformly severe only in the three for whom estimated age at death was 39-43 years. In turn, enamel wear appears to have been the direct cause of abscess development, periodontal disease, and tooth loss. Periodontal disease was commonly expressed as alveolar resorption, particularly around the premolars and molars. This involvement was variable in all except the two youngest. Some interesting wear patterns were evident in the form of deep grooves in the upper incisors and dramatic notching of the lower canines. These patterns, and enamel attrition in general, were attributed to normal mastication and to various stripping activities. Only one carious lesion was observed, in a male with an estimated age of 26 years. An accurate assessment of the actual prevalence of caries was obscured by enamel wear and tooth loss in the older individuals.  相似文献   

17.
The overall density of 17 large herbivore species encountered during the study differed among species and habitat types, but not between seasons. There were clear seasonal patterns of association among species, which were more pronounced during wet than dry seasons, suggesting greater habitat selectivity and increased ecological separation. The defassa waterbuck (Kobus ellypsiprymnus defassa Ruppel) showed ecological separation from other species, possibly because it competitively displaced them.  相似文献   

18.
Hearts, diaphragms, esophagi, and spinal cords from 266 horses were obtained at slaughter in Creston, Ohio. Tissues were examined microscopically for Sarcocystis in sections, digested in trypsin to obtain bradyzoites, and fed to 10 dogs and 10 cats. Intramuscular cysts were found in selections of two hearts from 57 horses and four esophagi from 107 horses. The cysts were up to 900 micron long and up to 70 micron wide. The cyst wall was 1 to 2 micron thick and cross-striated. The enclosed bradyzoites were banana-shaped, 15 to 20 by 20 to 3 micron, and contained several PAS-positive granules. Bradyzoites were found in trypsin digests of seven of 57 (13%) equine tissues (heart, diaphragm, esophagus but not spinal cord) in one experiment and 10 of 47 (21%) esophagi, eight of 47 (17%) diaphragms but none of 47 hearts and spinal cords in another experiment. All of 10 dogs shed sporulated sporocysts or oocysts in feces 12 to 15 days (12 in one, 13 in eight, and 15 days in one) after digesting tissues from 169 horses. The sporocysts were 11 to 13 (12.0 +/- 0.5) by 7 to 8.5 (7.9 +/- 0.5) micron. In histologic sections of canine small intestine the sporocysts were located in the lamina propria near the tips of the villi. The 10 cats fed tissues from 266 horses did not shed Sarcocystis. A new name, S. fayeri, is proposed for this organism. Sarcocystis fayeri sporocysts (12 by 8 micron) are shorter than those of S. betrami (15 by 10 micron), the other species of Sarcocystis from the horse. The prepatent period is 12 to 15 days for S. fayeri and 8 days for S. bertrami (synonym S. equicanis Rommel and Geisel 1975).  相似文献   

19.
《Plains anthropologist》2013,58(55):1-10
Abstract

The presence of great herds of buffalo on the Central and Southern High Plains in early historic times may have been a recent phenomenon that discouraged reoccupation of the area by horticultural groups and encouraged proto-Apacheans who were already hunters of large herd animals to move southward. Such a possibility is supported by both archaeological and historical evidence.  相似文献   

20.
Histological sections of tongues, esophagi, and diaphragms from 512 adult ewes from the northwest United States and Texas were examined for Sarcocystis spp. Sarcocysts were found in sections of 82.1% of 504 tongues, 44.4% of 478 esophagi, and 51.7% of 89 diaphragms. Sarcocystis tenella was the predominant species and was found in 430 (84.0%) sheep; S. arieticanis was found in 18 (3.5%) sheep. The mean number of S. tenella sarcocysts in tissue sections was approximately 10 times higher than that of S. arieticanis. The identification of S. arieticanis was confirmed by ultrastructural studies and by transmission to dogs. Macroscopic sarcocysts of S. gigantea were also found but were not quantitated in all sheep; sarcocysts of S. medusiformis were not observed.  相似文献   

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