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991.
Ouédraogo-Koné S Kaboré-Zoungrana CY Ledin I 《Tropical animal health and production》2008,40(2):155-164
Foliage of Afzelia africana, Pterocarpus erinaceus and Khaya senegalensis, from 10 trees per species, was collected every two weeks during the late dry, rainy and cool season to determine the seasonal
effects on chemical composition. Fifteen rams of the Djallonké breed, weighing on average 20.0 kg, were used to evaluate the
voluntary intake and digestibility of hay of A. gayanus, foliage of A. africana (as a sole feed), and A. africana, P. erinaceus and K. senegalensis offered with 30% of the diet as A. gayanus hay. The crude protein (CP) content of A. africana, and P. erinaceus decreased significantly from the late dry season to the cool season when that of K. senegalensis tended to increase. The mean CP of A. africana, P. erinaceus and K. senegalensis differed significantly (173 g, 139 g and 114 g/kg DM, respectively). The DM intake of A. africana offered with hay (571 g/d) or as a sole feed (598 g/d) were not significantly different, but was higher than that of P. erinaceus (428 g/d) and K. senegalensis (298 g/d). The digestibility calculated by difference of DM and CP of A. africana (582 g/kg DM and 795 g/kg CP, respectively) did not differ significantly from A. africana as a sole feed, but were higher than for the other species. The nutritive value of A. africana seems to justify the high preference of herders for this species. 相似文献
992.
Cryptosporidiosis in buffalo calves (<Emphasis Type="Italic">Bubalus bubalis</Emphasis>): Prevalence and potential risk factors 总被引:1,自引:0,他引:1
The objective of the present study was to describe the prevalence and risk factors associated with cryptosporidiosis in buffalo calves in Middle Egypt. During one year, 458 fecal samples were collected from buffalo calves less than 3 month age in 55 small scale herds and examined for the presence of Cryptosporidium oocysts. Data describing age, gender, season, and herd management practices were gathered to assess potential risk factors. Fecal examination showed that 14.19% of the examined calves were positive for Cryptosporidium spp. Calves at 1-15 days were at the highest risk (P < 0.001), and a significant relationship between season and infection (P < 0.05) was recorded. A significant association between infection and hygiene (P < 0.001), type of floor (P < 0.01) and source of water (P < 0.01) was also recorded. Statistical analysis concerning the clinical signs and fecal characteristics revealed a significant association with fecal consistency (P < 0.001), presence of blood (P < 0.01) and mucous (P < 0.01). Moreover, a significant association was found between infection and the desire for suckling (P < 0.05) and tenesmus (P < 0.05). The results of the present study demonstrated the strong relation between infections by Cryptosporidium spp. and diarrhea in buffalo calves. 相似文献
993.
After very hot summer, 22 sheep from 5 different flocks consisting of approximately 150-200 animals each were diagnosed with facial eczema in September 2005, in southwest Turkey. Photophobia, corneal opacity, severe ulcers of the facial skin, especially localized around the eyes and mouth, and 3% mortality were the most prominent clinical symptoms. GGT levels of the animals were very high and varying between 261- 328 U/l. While the activities of ALT and total bilirubin were elevated and AST was normal in affected sheep. Total bilirubin level was higher than normal. Seven of the 22 sheep were euthanatized and necropsy was performed on all of these animals. Severe icterus, hepatomegaly, enlarged gallbladder, congestion of mesenteric vessels were the common necropsy findings. Histopathological changes of the liver included necrosis of the hepatocytes, cholangiohepatitis characterized by mononuclear inflammatory cell infiltrate in the portal area and mild to severe fibrosis around bile ducts. A diagnosis of sporidesmin toxicosis was made based on the histopathology of the livers, the elevation in liver enzymes, and the development of cutaneous lesions consistent with photosensitization and high spore counts in the ruminal contents. Surviving sheep were treated with procaine penicillin + dihidrostreptomycin sulfate, multivitamin complexes and flunixin meglumine. Additionally, zinc sulphate was also given at a dose of 6 gr per 100 lt drinking water for 28 days. All treated sheep recovered. Pasture spore counts were between 96,300- 267,500 spores/g grass. 相似文献
994.
Giammarioli M Pellegrini C Casciari C De Mia GM 《Veterinary research communications》2008,32(3):255-262
995.
Shiilegdamba E Carpenter TE Perez AM Thurmond MC 《Veterinary research communications》2008,32(3):201-207
Prior to 2000, foot-and-mouth disease (FMD) had not been observed in Mongolia since 1973; however, between April 2000 and
July 2002, Mongolia reported 44 FMD outbreaks that affected cattle, sheep, goats, and camels. The objectives of this study
were to describe the distributions of the 44 reported FMD outbreaks in Mongolia and to assess their spatial clustering and
directions of movement. Official reports were collected to obtain the number and species of animals both affected and at risk,
and the date and geographical coordinates of each outbreak. Significant global and local spatial clusters of reported FMD
outbreaks were identified. Disease spread during the second epidemic moved 76° northeast and the spread of the disease during
the third epidemic moved 110° northwest. FMD outbreaks were clustered intensely close to other FMD-positive counties. These
findings can be used in the future to help plan prevention and control measures in high risk areas. 相似文献
996.
Mestorino N Formentini EA Lucas MF Fernandez C Modamio P Hernández EM Errecalde JO 《Veterinary research communications》2008,32(1):21-33
A comparative pharmacokinetic study was conducted to determine the order and the rate of absorption of triclabendazole (TCBZ)
in cattle and sheep. A commercial suspension of TCBZ (Biofasiolex, Biogénesis S.A., Argentina) was administered at a dose
rate of 10 mg/kg by the oral route to six Holstein female calves and six Corriedale female sheep. The plasma concentration
profiles of the metabolites triclabendazole sulfoxide (TCBZ-SO) and triclabendazole sulfone (TCBZ-SO2) were analysed by means of the non-compartmental method. The order of the absorption process of the active metabolite, TCBZ-SO,
was determined by construction of curves of cumulative absorbed fraction of the drug by means of the Wagner-Nelson method.
The appearance of TCBZ-SO in plasma of cattle and sheep resembles the entry of a constant quantity of drug into the organism
per unit time. This is explained by the reservoir effect of the rumen, which acts as a biological slow-release system for
TCBZ-SO and its precursor TCBZ to the posterior digestive tract where they are absorbed. The plasma concentration profiles
of TCBZ-SO in both species were well described by a one-compartment open model with zero-order process of absorption and first-order
process of elimination. The values of AUC0-∞ and C
max of TCBZ-SO did not differ between species, while other kinetic parameters except for λ
z
had higher values in calves than in sheep. In the case of TCBZ-SO2, t
max was the only parameter that did not differ between species, while other kinetic parameters except for λ
z
had higher values in calves than in sheep. 相似文献
997.
Randhawa SS Dua K Randhawa CS Randhawa SS Munshi SK 《Veterinary research communications》2008,32(8):599-608
The effect of biotin supplementation on various foot lesions and hoof ceramide composition of toe (wall) and sole portions
of hooves was studied in crossbred dairy cattle. Biotin supplementation was done for five months in 14 cattle at a farm and
the other 14 animals kept as control. A significant decline was observed in heel erosions and sole avulsions along with total
disappearance of white line fissures and double soles in the biotin supplemented cattle resulting in decrease in the overall
disease score. Thin layer chromatographs of the hoof lipids revealed 11 types of ceramides in sole lipids and 6 types of ceramides
in toe (wall) lipids. The ceramides were typed and identified according to their Rf values. A qualitative increase in the
density of thin layer chromatographs of sole lipids was observed in biotin supplemented cattle whereas a non-significant difference
in density of thin layer chromatographs of toe lipids was observed after supplementation of biotin. 相似文献
998.
Conservationists, managers, and land planners are faced with the difficult task of balancing many issues regarding humans
impacts on natural systems. Many of these potential impacts arise from local-scale and landscape-scale changes, but such changes
often covary, which makes it difficult to isolate and compare independent effects arising from humans. We partition multi-scale
impacts on riparian forest bird distribution in 105 patches along approximately 500 km of the Madison and Missouri Rivers,
Montana, USA. To do so, we coupled environmental information from local (within-patch), patch, and landscape scales reflecting
potential human impacts from grazing, invasive plant species, habitat loss and fragmentation, and human development with the
distribution of 28 terrestrial breeding bird species in 2004 and 2005. Variation partitioning of the influence of different
spatial scales suggested that local-scale vegetation gradients explained more unique variation in bird distribution than did
information from patch and landscape scales. Partitioning potential human impacts revealed, however, that riparian habitat
loss and fragmentation at the patch and landscape scales explained more unique variation than did local disturbances or landscape-scale
development (i.e., building density in the surrounding landscape). When distribution was correlated with human disturbance,
local-scale disturbance had more consistent impacts than other scales, with species showing consistent negative correlations
with grazing but positive correlations with invasives. We conclude that while local vegetation structure best explains bird
distribution, managers concerned with ongoing human influences in this system need to focus more on mitigating the effects
of large-scale disturbances than on more local land use issues.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
999.
Olga Viedma 《Landscape Ecology》2008,23(6):657-672
Mediterranean landscapes are dynamic systems that undergo temporal changes in composition and structure in response to disturbances,
such as fire. Neither landscape patterns nor driving factors that affect them are evenly distributed in space. Accordingly,
disturbances and biophysical factors interact in space through time. The aim of this paper is to assess the relative influence
of topography and fire on the landscape patterns of a large forested area located in Sierra de Gredos (Central Spain) through
time. A series of Landsat MSS images from 1975 to 1990, and a digital elevation model (DEM) were used to map fires, assess
topographical complexity and evaluate changes in landscape composition and structure. Functional regions across the entire
landscape were identified using different classification criteria (i.e., percentage burned area and topographic properties)
to model topographic and fire impacts at regional scales. A canonical variance partition method, with a time series split-plot
design, quantified the relative influence and co-variation of topography and fire on land cover patterns through time. Main
results indicated that analyzing portions of the landscape under similar environmental conditions and fire histories, the
effects of different fire regimes on the spatio-temporal dynamics of main land covers can be highlighted. However, the impact
of fire on landscape patterns was high variable among regions due to the different regeneration abilities of main land covers,
the topographic constraints and the fire histories of each region. Hence, broad patterns of fire related variance and co-variation
with topography emerged across the entire area due to the different conditions of each landscape portion in which this large
Mediterranean landscape was divided.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
1000.
David J. Augustine Stephen J. Dinsmore Michael B. Wunder Victoria J. Dreitz Fritz L. Knopf 《Landscape Ecology》2008,23(6):689-697
Sylvatic plague is a major factor influencing the dynamics of black-tailed prairie dog (Cynomys ludovicianus) colonies in the western Great Plains. We studied the nesting response of the mountain plover (Charadrius montanus), a grassland bird that nests on prairie dog colonies, to plague-driven dynamics of prairie dog colonies at three sites in
the western Great Plains. First, we examined plover nest distribution on colonies that were previously affected by plague,
but that had been recovering (expanding) for at least 6 years. Plovers consistently nested in both young (colonized in the
past 1–2 years) and old (colonized for 6 or more years) portions of prairie dog colonies in proportion to their availability.
Second, we examined changes in plover nest frequency at two sites following plague epizootics, and found that mountain plover
nest numbers declined relatively rapidly (≤2 years) on plague-affected colonies. Taken together, our findings indicate that
available plover nesting habitat associated with prairie dog colonies closely tracks the area actively occupied by prairie
dogs each year. Given the presence of plague throughout most of the mountain plover’s breeding range in the western Great
Plains, important factors affecting plover populations likely include landscape features that determine the scale of plague
outbreaks, the distance that plovers move in response to changing breeding habitat conditions, and the availability and quality
of alternate breeding habitat within the landscape. 相似文献