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排序方式: 共有132条查询结果,搜索用时 500 毫秒
71.
Souza PE Oliveira SS Aguiar-Filho CR Cunha AL Albuquerque RF Evêncio-Neto J Riet-Correa F Mendonça FS 《Research in veterinary science》2012,93(3):1337-1340
Three outbreaks of primary photosensitization caused by Froelichia humboldtiana are reported in the semiarid region of the states of Pernambuco and Paraíba, in northeastern Brazil. The disease occurred from March to June 2011, affecting 27 bovines out of a total of 70. The main lesions consisted of dermatitis of the white skin, with edema and necrosis. All the bovines recovered after removal from the areas invaded by F. humboldtiana. To produce the disease experimentally, one bovine with white skin was placed for 14days into an area with F. humboldtiana as the sole forage. This bovine presented photodermatitis on the third day of consumption. The serum concentrations of total, indirect, and conjugated bilirubin and the serum activities of gamma-glutamyl transferase (GGT) and aspartate-aminotransferase (AST) in the spontaneously affected cattle and in the experimental cattle remained within normal ranges. It is concluded that F. humboldtiana causes primary photosensitization in cattle in northeastern Brazil. 相似文献
72.
Abe Flavia R. Machado Angela A. Coleone Ana C. da Cruz Claudinei Machado-Neto Joaquim G. 《Water, air, and soil pollution》2019,230(3):1-13
Water, Air, & Soil Pollution - Triclosan (TCS) is a potential endocrine-disrupting compound (EDC), which produces an adverse impact on aquatic life and human beings. Wastewater discharge is... 相似文献
73.
Factors affecting longevity in maternal Duroc swine lines 总被引:3,自引:0,他引:3
Joaquim Tarrs Joan Tibau Jesús Piedrafita Emma Fbrega Josep Reixach 《Livestock Science》2006,100(2-3):121-131
A competing risks approach was used to evaluate the influence of several pre-farrowing factors on risk of culling due to different causes in Duroc swine, these having low fertility, low productivity, lameness and mortality. Culling due to low fertility increased for average daily gains during the growth test lower than 585 g/day, whereas culling due to low productivity and mortality increased with low levels of backfat thickness at the end of the growth test. Lesser loin depths at first farrowing reduced culling due to low productivity but increased culling due to lameness. Furthermore, a higher average daily gain from the end of the growth test to first mating increased culling by all causes. A complementary analysis was carried out to evaluate the influence of these factors on risk of culling without taking into account the specific reason of failure. In this second analysis, the factors were included as time-dependent covariates whose relative importance changed throughout the sows' productive life. Expected survival functions and replacement rates have been calculated in different hypothetical situations in order to determine the optimal animal body type at first farrowing to maximise longevity, which under our production conditions is independent of average daily gain from birth until the end of the growth test, but from the end of the growth test to first mating average daily gain should not be over 485 g/day; backfat thickness should be more than 16 mm at the end of the growth test and maintain this level until the first parturition without exceeding 19 mm; loin depth should be kept below 45 mm at first farrowing. 相似文献
74.
Ana Paula Barreira Joaquim J. S. Ramalho Thomas Panagopoulos Maria Helena Guimarães 《Growth and change》2017,48(4):853-868
Despite the worldwide trend of urbanisation, data reveal that some cities are growing whereas others are losing inhabitants. To assess such dynamics in Portuguese cities, demographic, employment, housing, and climate variables were analysed as possible drivers of population change for the period 1991–2011. Panel data models show that higher shares of employment in the secondary and tertiary sectors, higher maximum temperatures, and a higher proportion of middle‐aged vacant houses act as pull factors attracting inhabitants, whereas a higher unemployment rate is a push factor for cities. 相似文献
75.
Janelle M. R. Curtis Joaquim Ribeiro Karim Erzini Amanda C. J. Vincent 《水产资源保护:海洋与淡水生态系统》2007,17(5):468-484
- 1. A 2‐year experimental seining programme and underwater visual censuses were undertaken to quantify the direct effects of active demersal fishing on the population structure and relative abundance of two sympatric seahorse species of conservation concern: the European long‐snouted seahorse, Hippocampus guttulatus Cuvier 1829 and the short‐snouted seahorse, Hippocampus hippocampus L. The influence of habitat preference on population‐level responses to changes in habitat structure following a reduction in fishing effort was also investigated.
- 2. It was predicted that the benthic habitat would be more structurally complex after fishing ceased and that seahorse densities would increase in response to reduced fishing mortality. Furthermore, it was predicted that the magnitude of the increase in density would be greater for H. guttulatus than for H. hippocampus, because the former species prefers complex vegetated habitats while the latter species uses sparsely vegetated habitats.
- 3. As predicted, the amount of habitat cover increased significantly when seining ceased, primarily through increases in the abundance of drifting macroalgae and unattached invertebrates. Despite similarities in life histories, the two seahorse species responded differently in terms of magnitude and direction to reduced fishing effort: the abundance of H. guttulatus increased significantly while H. hippocampus decreased in abundance.
- 4. Results suggest that active demersal fishing may influence the magnitude and direction of the responses of benthic marine fishes to exploitation through its impacts on habitat structure. An increase in habitat cover appeared to favour higher densities of H. guttulatus when seining effort was reduced. By contrast, repeated seining, which maintained less complex habitats, appeared to favour greater abundances of H. hippocampus.
- 5. Given differences in habitat preference among benthic marine fishes subject to incidental capture in fisheries, simultaneous attempts to manage populations of sympatric species may require complementary strategies that support the persistence of diverse habitat types.
76.
DA El‐Badry RH Mohamed HA EL‐Metwally TR Abo Al‐Naga 《Reproduction in domestic animals》2017,52(3):522-525
The cryopreserved camel semen is often associated with poor quality and fertility. This study aimed to improve the dromedary frozen semen quality by comparing the efficiency of four cryoprotectant agents (CPAs) on sperm freezability. Semen samples were collected from seven male Maghrabi camels, diluted with Shotor diluent supplemented with glycerol (Sh‐G), dimethyl formamide (DMF, Sh‐DF), dimethyl sulfoxide (DMSO, Sh‐DS) or ethylene glycol (EG, Sh‐EG), all at 6% final concentration, and the samples were subjected to cryopreservation. The results revealed the superiority of Sh‐DF over Sh‐G and Sh‐DS in terms of post‐thaw motility (55.83 ± 2.20 vs. 47.50 ± 4.33 and 45.00 ± 2.89%, respectively), sperm membrane (49.00 ± 0.58, 39.33 ± 3.33 and 42.67 ± 1.45%, respectively) and acrosomal integrities (53.00 ± 0.58, 57.33 ± 0.88 and 52.33 ± 1.45%, respectively). Sh‐EG group showed the lowest post‐thaw motility, plasma membrane and acrosome integrities (12.50 ± 1.44, 22.67 ± 1.45 and 30.67 ± 1.45, respectively). In conclusion, the protocols of dromedary camel semen cryopreservation could be enhanced using 6% DMF as a cryoprotectant agent. 相似文献
77.
There has been a worldwide increase in the number and geographical spread of wild boar populations in recent decades leading to an increase in both the circulation of disease agents and greater contact with domestic animals and humans. Diseases affect the population dynamics of wildlife but the effects of most viral diseases on the European wild boar are largely unknown. Many viral diseases present in domestic pig populations are also present in wild boars where they can provide a disease reservoir, as is clearly the case with classical swine fever, but little is known about other viral diseases such as porcine circovirus diseases or hepatitis E. This review considers the current scientific knowledge of the effects of viral diseases on wild boar populations and their r?le as potential disease reservoirs. The focus is on those viral diseases of domestic swine and wild boars that are included as notifiable by the Office International des Epizooties (OIE). 相似文献
78.
Joaquim Trindade-Filho Fernando Landa Sobral Marcus Vinicius Cianciaruso Rafael Dias Loyola 《Biological conservation》2012,146(1):155-162
Land-use intensification causes species losses reducing phylogenetic and functional trait diversity as well as ecosystem function. Phylogenetic (PD) and functional (FD) diversity of regional assemblages have been identified as a key to understanding ecosystem and community functioning, yet it has been rarely included in conservation planning. The use of indicator groups to represent species richness is by far the most common measure used for developing plans to conserve current and future biodiversity. Could indicator groups be used for representing PD and FD of whole assemblages? Using a continuous measure of PD and FD derived from phylogenies and quantitative functional traits of species and their functional relationships, we assessed the effectiveness of 16 indicator groups in representing these evolutionary and functional components of biodiversity to answer this question. We focused our analyses on the entire set of 854 bird species occurring in the Atlantic Forest Biodiversity Hotspot, as a case study. We show that a particular bird order (Apodiformes) is the most effective surrogate group to capture PD, while the Charadriiformes and restricted-range species are the most effective surrogate group to capture FD. Their use as a shortcut to conservation planning is likely to guarantee the conservation of evolutionary and ecosystem processes through the representation of the unique species, as well as ecosystem stability in the long term, with the representation of the redundant species. 相似文献
79.
NH Damrauer G Cerullo A Yeh TR Boussie CV Shank JK McCusker 《Science (New York, N.Y.)》1997,275(5296):54-57
Time-resolved absorption spectroscopy on the femtosecond time scale has been used to monitor the earliest events associated with excited-state relaxation in tris-(2,2'-bipyridine)ruthenium(II). The data reveal dynamics associated with the temporal evolution of the Franck-Condon state to the lowest energy excited state of this molecule. The process is essentially complete in approximately 300 femtoseconds after the initial excitation. This result is discussed with regard to reformulating long-held notions about excited-state relaxation, as well as its implication for the importance of non-equilibrium excited-state processes in understanding and designing molecular-based electron transfer, artificial photosynthetic, and photovoltaic assemblies in which compounds of this class are currently playing a key role. 相似文献
80.
D. Z. Pellegrini T. R. Müller J. H. Fonteque L. P. de Souza A. F. de Souza J. G. F. Joaquim 《Equine Veterinary Education》2020,32(5):268-277
This review discusses the applications of acupuncture (AP) and its eastern medical philosophy in equine health, and the main techniques used to stimulate acupoints in equine practice. These methods include dry needling, electroacupuncture (EA), moxibustion, laser therapy, haemopuncture, aquapuncture, pharmacopuncture, acupressure and gold implants. 相似文献