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981.
982.
We have carried out an aetiological and pathological study of an outbreak of septicaemia caused by the O165 serogroup of Escherichia coli in Japanese quail (Coturnix coturnix japonica) which resulted in high mortality (90%). After treatment with amoxicilin in drinking water (200 mg/l), morbility and mortality rates dropped markedly. Microbiological studies showed that the organism responsible was an atypical E. coli strain, on the basis of the non-fermentation of lactose (ONPG-), which belonged to the O165 serogroup and was highly virulent for 1-day-old chickens.  相似文献   
983.
The objective of this study was to evaluate the feasibility, efficacy and complications following lavage and drainage of the lateral compartment (LC) of the equine guttural pouch (GP) using a modified Garm's technique (MGT). In an ex vivo study (study 1), six cadaver heads were examined to assess the anatomical limits of the surgical approach and whether vital structures might be damaged. This was followed by an in vivo study (study 2) in which a lavage/drainage tube was placed for 3 days into each LC of four standing horses using the MGT. In both studies, the procedure offered direct access into the LC and indirect access into the medial compartments of the GP. In study 1, the MGT provided a rostroventral point of access allowing drainage of the LC, with no obvious iatrogenic damage. In study 2, the MGT permitted lavage of the entire GP in three healthy horses and one horse with mild GP empyema. The only major complication was development of emphysema of the lateral wall of one LC, with secondary collapse of the mucous membrane. The time for secondary wound healing was 12-14 days. The MGT can be performed safely in standing horses and may be of value in providing access for lavage and drainage in horses with mild GP empyema.  相似文献   
984.
985.
Abstract

The study evaluates the first three parities of 144 Swedish Landrace×Yorkshire sows from three certified organic and three conventional commercial piglet-producing herds. Sows and litters were weaned at seven and five weeks post partum (pp) in organic and conventional herds, respectively. Herdsmen judged sow behaviour and maternal ability at farrowing, two weeks pp and at weaning. Herdsmen collected registrations of litter size, litter weight and sow fat status at farrowing and at weaning. Piglet mortality and oestrous signs were registered continuously during the nursing period. Sows in organic herds were scored to be more cautious among piglets, and to have better nursing behaviour and maternal ability in early lactation than sows in conventional herds. Piglet mortality was higher in organic than in conventional herds. Oestrus during lactation was only observed among sows in organic herds, and sows showing oestrus during lactation were fatter at weaning.  相似文献   
986.
An adult, male, green iguana (Iguana iguana) of unknown age was presented with a history of an enlarging, dark, skin mass in the right axillary region. The mass was excised because neoplasia was suspected. Impression smears of the cut surface of the mass were prepared for cytologic examination, and the mass was fixed for histologic examination. The impression smears contained numerous, discrete, pigmented, neoplastic cells consistent with melanin-producing neoplastic chromatophores. Histologic findings were consistent with a cutaneous melanophoroma. By transmission electron microscopy, the intracytoplasmic pigment granules corresponded to numerous melanosomes and lower numbers of premelanosomes. Tissue sections of the tumor were immunoreactive for Melan A antigen and were negative for S-100 antigen. The cytologic, histologic, electron microscopic, and immunohistochemical findings of the neoplasm were consistent with those of melanophoroma, an uncommon neoplasm of reptiles. The present report augments the limited body of knowledge on cytomorphologic and immunohistochemical characteristics of pigmented neoplasms in reptiles.  相似文献   
987.
The use of a simulation package to study the consequences of various water allocation policies during time of water shortage is described. The study shows that simulation can be a valuable aid to irrigation scheme managers in their decision making.  相似文献   
988.
989.
Giant piezoelectricity on Si for hyperactive MEMS   总被引:1,自引:0,他引:1  
Microelectromechanical systems (MEMS) incorporating active piezoelectric layers offer integrated actuation, sensing, and transduction. The broad implementation of such active MEMS has long been constrained by the inability to integrate materials with giant piezoelectric response, such as Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PMN-PT). We synthesized high-quality PMN-PT epitaxial thin films on vicinal (001) Si wafers with the use of an epitaxial (001) SrTiO(3) template layer with superior piezoelectric coefficients (e(31,f) = -27 ± 3 coulombs per square meter) and figures of merit for piezoelectric energy-harvesting systems. We have incorporated these heterostructures into microcantilevers that are actuated with extremely low drive voltage due to thin-film piezoelectric properties that rival bulk PMN-PT single crystals. These epitaxial heterostructures exhibit very large electromechanical coupling for ultrasound medical imaging, microfluidic control, mechanical sensing, and energy harvesting.  相似文献   
990.
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