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11.
The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty‐nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post‐weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning‐to‐oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation.  相似文献   
12.
Strangulating obstruction of the small intestine by anomalous mesenteric bands is an uncommon cause of colic in horses. The most commonly reported bands are mesodiverticular bands that are embryological remnants of the vitelline arteries. Despite the congenital nature of the anomaly, a wide age range of horses can be affected. This report describes a case of small intestinal strangulating obstruction caused by an unusual, anomalous congenital band attached to the ileocaecal fold in a yearling colt. Information including case background, history, clinical, laboratory, surgical and pathological findings is described.  相似文献   
13.
To assess the stress level of cheetahs reared in Japan and to identify the prime components of the climatic conditions that affect their thermal stress, fecal corticosterone was monitored for 8 months from May to the following January. A total of 203 fecal samples were gathered in the morning from seven adult cheetahs that were kept at a zoological garden in Wakayama, Japan. Cheetahs were on exhibit singly or together with a harmonious conspecific during the day, but housed singly at night. Although the monthly fluctuation in corticosterone concentrations was not significant, the concentrations were relatively low during the summer season. Individual differences among cheetahs and the interaction effect between individual and month on the corticosterone concentrations were significant. Whereas the corticosterone concentrations negatively correlated with air temperature, they were positively correlated with the amount of rainfall. The highest air temperature and the amount of rainfall were extracted as the prime factors affecting corticosterone concentrations. These results suggest that cheetahs reared in Japan are somewhat subjected to thermal stress, particularly on cooler and/or rainy days.  相似文献   
14.
A meso-scale pilot plant was set up to test the efficiency of a phytoremediation technique applied to slightly contaminated marine sediments dredged from the port of Livorno (central Italy). The technique applied involved the use of plants (a grass species, Paspalum vaginatum and a shrub species, Tamarix gallica) and earthworms (Eisenia foetida sp.) in order to recreate an active ecosystem in which plants, micro- and macroorganisms could interact with each other through the rhizosphere, for the adsorption, extraction and/or degradation of pollutants. This system enables plants to grow in a fine textured and salt medium highly unsuitable for plant species, and a physical, chemical and biological amelioration of the matrix was observed at the end of the experimentation (after 9 months). The sediment was bio-physically pre-conditioned by mixing it with calcareous material from excavating activities (5:1?v/v) and applying green compost. The presence of microorganisms in the rhizosphere and the earthworms produced a reduction by about 50% of the initial total petroleum hydrocarbon content. The use of a natural chelator with phyto-hormonal properties (humic substances) showed their capability of forming stable complexes, especially with Pb, and their contribution as an agronomic fertiliser. The combined effect of the P. vaginatum and T. gallica in the extraction of heavy metals from the sediment showed promisingly high percentages of metal effectively extracted in comparison with its available fraction (e.g. available Ni = 6.2%; Ni extracted = 15.7%). The technique proposed could be promising for an operational re-use of dredged marine sediments for agricultural purposes, a suitable final destination for the great majority of these contaminated materials from rivers and harbour docks.  相似文献   
15.
Two beams of light can be quantum mechanically entangled through correlations of their phase and intensity fluctuations. For a pair of spatially extended image-carrying light fields, the concept of entanglement can be applied not only to the entire images but also to their smaller details. We used a spatially multimode amplifier based on four-wave mixing in a hot vapor to produce twin images that exhibit localized entanglement. The images can be bright fields that display position-dependent quantum noise reduction in their intensity difference or vacuum twin beams that are strongly entangled when projected onto a large range of different spatial modes. The high degree of spatial entanglement demonstrates that the system is an ideal source for parallel continuous-variable quantum information protocols.  相似文献   
16.
Hematopoietic stem cell (HSC) gene therapy for adenosine deaminase (ADA)-deficient severe combined immunodeficiency (SCID) has shown limited clinical efficacy because of the small proportion of engrafted genetically corrected HSCs. We describe an improved protocol for gene transfer into HSCs associated with nonmyeloablative conditioning. This protocol was used in two patients for whom enzyme replacement therapy was not available, which allowed the effect of gene therapy alone to be evaluated. Sustained engraftment of engineered HSCs with differentiation into multiple lineages resulted in increased lymphocyte counts, improved immune functions (including antigen-specific responses), and lower toxic metabolites. Both patients are currently at home and clinically well, with normal growth and development. These results indicate the safety and efficacy of HSC gene therapy combined with nonmyeloablative conditioning for the treatment of SCID.  相似文献   
17.
18.
The prevailing environmental conditions, temperature in particular, drive seasonal changes both in leaf development and stomatal characteristics. In order to ascertain the effect of increases in climatic water deficit on some leaf and stomatal parameters under field conditions, a study was carried out on two sets of leaves (spring and summer) on a large sample of Amygdalus communis L. cultivars in comparison with several Amygdalus webbii Spach seedlings, a species more adapted to arid environments and probable ancestor of cultivated almonds. Observations were performed between spring and summer of a particularly hot season. The results showed a significant and general reduction of both leaf area and stomatal frequency and an increase in stomatal size. Nevertheless, there were evident differences between cultivated and wild almonds. A stronger reduction of leaf area was observed in A. webbii (−31%) with respect to A. communis (−14%); on the contrary, the latter reduced stomatal frequency more than the former (−25% and −19%, respectively). The examined cultivated almonds, in response to the increase in climatic water deficit, tended to arrange their stomatal structures like those of wild almonds. Finally, increasing the climatic water deficit, the slope of the linear regressions between stomatal frequency and size did not change in either species, leading to a better understanding of the mechanisms of almond acclimation to environmental stresses.  相似文献   
19.
Successful carnivore conservation depends on public attitudes and acceptance levels of carnivores, and these are likely to change as circumstances change. Attitude studies repeated in time that can demonstrate such change are rare. Our study surveyed Croatian rural inhabitants in 2002 and in 2008 and analyzed their responses to detect a change in attitudes toward brown bears (Ursus arctos) over time. Important developments occurring in Croatia at the time of our research included a more centralized and more clearly defined bear management strategy, and an increase in the bear population. We constructed models to explain respondent’s value orientations, their level of perceived threat and their acceptance capacity for bears. Findings show that while value orientations and the overall level of perceived threat did not change over time, bear acceptance capacity was reduced. This suggests that the increase in the bear population and perhaps the more centralized bear management reduced respondents’ willingness to accept a larger bear population. We conclude that continuous public involvement in bear management is essential in order to maintain a feeling of control over the bear among the local population. Furthermore we argue that hunting is an important form of public involvement in the region, serving to reinforce existence and bequest values of the bear and increase its public acceptance.  相似文献   
20.
Penicillium mycosis, or penicilliosis, is rare in animals. This report describes the clinical signs and pathological, immunohistochemical, and biomolecular findings in a case of avian penicilliosis in a Congo African grey parrot. On gross necropsy, pyogranulomatous changes were identified in the lung, liver, and kidney. Histopathology demonstrated periodic acid Schiff-(PAS) and Grocott-positive hyphae in these tissues. Immunohistochemistry confirmed the genus of the fungus and polymerase chain reaction (PCR) confirmed a high homology with Penicillium chrysogenum.  相似文献   
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