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61.
Fluid accumulation in mouse ligated intestine inoculated with the vascular permeability factor produced by Bacillus cereus. 总被引:1,自引:0,他引:1
K Shinagawa K Sato H Konuma N Matsusaka S Sugii 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(2):167-171
Partially purified vascular permeability (VP) factor (VPF) of Bacillus cereus induced fluid accumulation in the ligated intestinal loops of mouse (MIL) and rabbit (RIL), suggesting that the VP activity may correlate with fluid accumulation in ligated intestinal loops of these animals. Fluid accumulation was observed at 6-8 hr in 55-67% of mouse intestinal loops inoculated with 40-50 immunodiffusion units (IDU) of partially purified VPF, whereas it was found at 2 hr in all loops with 400-600 IDU of partially purified VPF. In rabbit intestinal loops with 120-190 IDU of partially purified VPF, fluid accumulation was observed at 6 hr. From these findings, VPF produced by B. cereus can be easily detected in both MIL and RIL. The intestinal tissue of mouse intestinal loops was histopathologically damaged at different concentrations of the VPF to induce fluid accumulation. With 50 IDU of partially purified VPF, severe edema was found in the laminia proprial layer and submucosa. With 600 IDU of partially purified VPF, on the other hand, severe necrosis in the surface epithelium of villus and laminia proprial layer, and hyperemia in the submucosa were observed, suggesting that partially purified VPF may be cytotoxic and/or intestinecrotic. 相似文献
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2 groups of 20 cocks each were selected at random from non-dwarf White Leghorn (28 weeks post-hatch) and dwarf Krishna-J (38 weeks post-hatch) genotypes. The treated groups comprised 10 White Leghorn and 10 Krishna-J cocks. The remaining birds served as controls. 8 weeks prior to furazolidone treatment, semen was collected from both control groups at regular 4-day intervals, for 4 weeks. Cocks of the treated groups of both genotypes were administered furazolidone (0.14 g/bird/day) for 7 consecutive days. Semen was collected from all cocks at regular 4-day intervals for 4 weeks. Semen from the cocks of the same group was pooled. The pooled ejaculate volume and sperm density did not differ significantly in the 2 genotypes. The semen output as well as sperm density increased along with progressive attainment of sexual maturity. Furazolidone treatment caused significant reduction in semen volume as well as sperm concentration in either genotype. 相似文献
65.
The records of 71 horses with small intestinal disorders requiring surgical correction were disorders requiring surgical correction were reviewed to compare the prevalence of laminitis in those horses treated prophylactically with heparin and the prevalence of horses not treated with heparin. The prevalence of laminitis was 13% (9/71), and there was no significant difference (P less than 0.05) in the prevalence of laminitis between the 2 groups. The lack of significant benefit after treatment with heparin indicates that further work needs to be done on the equine coagulation system before heparin can be advocated for prevention of laminitis. 相似文献
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M A Albassam B J Houston P Greaves N Barsoum 《Journal of the American Veterinary Medical Association》1989,194(11):1595-1597
A 13-month-old Beagle became anorectic and had fever, stiff gait, and tenderness in the inguinal region. Clinical signs of disease were associated with neutrophilia and a decrease in the albumin-to-globulin ratio. The dog became clinically normal for 5 days after 3 days of treatment with penicillin G and dihydrostreptomycin. Clinical signs of disease recurred, and the dog was euthanatized after failing to respond to administration of a trimethoprim-sulfamethoxazole combination for 9 days. Disseminated arteritis was seen in the testes, epididymides, mesentery, coronary arteries, aorta, and thyroid gland. Lesions were seen in large and medium-sized arteries and varied from acute necrotizing arteries to a chronic lesion with organization and recanalization of thrombi. The clinical signs of disease resembled those of Beagle pain syndrome, described in laboratory Beagles. 相似文献
68.
Summary Reproduction and lamb production of three fat-tailed, carpet-wool Iranian breeds of sheep; Karakul (130 ewes), Mehraban (103) and Baluchi (119) were studied. The ewes were mated either as purebreds or with Corriedale or Targhee rams. The overall least-squares means for ewes mated (showed oestrus) or ewes exposed, ewes lambed or ewes mated, lambs born of ewes lambing (prolificacy), lambs born alive of total lambs born, lambs weaned of live lambs born, lambs weaned (75 days of age) of ewes mated, kg lamb weaned per ewe mated and kg lamb weaned per 100 kg ewe mated were 98.3%, 93.5%, 103.1%, 94.9%, 97.8%, 90.0%, 18.2 kg and 38.4 kg respectively. The native breeds were not different for any of the traits studied except for prolificacy which was higher in Mehraban than in Karakul. Purebred matings did not differ from the crossbred matings for any of the traits concerning the number of lambs but crossbreeding improved kg lamb weaned per ewe mated (9.2%, P=0.08) and kg lamb weaned per 100 kg ewe mated (10.0%, P<0.05). Among the three native breeds Karakul showed the largest improvement when crossed with the exotic rams for the traits concerning kg lambs weaned. Corriedale and Targhee rams had similar effects on all the traits studied. A lower percentage of virgin ewes showed oestrus, had a lower twinning rate and productivity compared with the mature ones. Sex was not a significant source of variation in lamb livability.
Desempeño Reproductivo De Tres Razas Cola Gruesa De Ovejas Apareadas Con Moruecos Nativos, Corridale Y Targhee
Resumen Se estudiaron la reproducción y producción de corderos iraníes de tres razas fat-tailed (Cola gruesa o grasosa) productores de lana para carpetas: Karakul (130 ovejas), Mehraban (103) y Baluchi (119). Las ovejas fueron apareadas como puras, o con moruecos Corridale o Targhee. Las medias mínimas cuadradas para ovejas apareadas (que mostraron estro) de ovejas expuestas, ovejas paridas de ovejas apareadas, corderos nacidos de ovejas paridas (prolificidad), corderos nacidos vivos del total de corderos nacidos, corderos destetados de corderos nacidos vivos, corderos destetados (75 días de edad) de ovejas apareadas, kg de cordero destetado por oveja apareada y kg de cordero destetado por 100 kg de oveja apareada, fueron: 98.3%, 93.5%, 103.1%, 94.9%, 97.8%, 90.0%, 18.2 kg y 38.4 kg respectivamente. Las razas nativas no fueron diferentes en ninguna de las características estudiadas, excepto por le prolificidad la cual fue mayor en Mehraban, que en Karakul. El apareamiento de razas puras, no difirió de los apareamientos cruzados para cualquiera de las características estudiadas concernientes con el número de corderos, pero el cruzamiento mejoró los kg. de cordero destetado por oveja apareada (9.2%,p<0.08) y kg de cordero destetado por 100 kg de oveja apareada (10.0%,P<0.05). De las tres razas nativas, la Karakul fue superior cuando se cruzó con las razas exóticas en lo concerniente a las características kg de cordero destetado. Las razas Corriedale y Targhee tuvieron efectos similares en todas las características estudiadas. Un bajo porcentaje de ovejas vírgenes ciclaron regularmente, tuvieron un porcentaje bajo de mellizos y productividad en general, comparada con las ovejas maduras. El sexo no fue una fuente significativa de variabilidad, en la supervivencia de los corderos.
Performances De Reproduction De Trois Races De Moutons À Queue Grasse Accouplées À Des Locales, Corriedale Et Targhee
Résumé La reproduction et la production d'agneaux de 3 races iranienes à queue grasse élevées pour la production de laine à tapis: karakul (130 brebis), Mehraban (103) et Baluchi (119) furent étudiées; Les brebis furent accouplées soit en race pure soit avec des béliers Corriedale ou Targhee; Les moyennes estimées par la méthode des moindres carrés de l'ensemble des brebis accouplées (oestrus visible) par rapport aux brebis exposées; des brebis agnelant par rapport aux brebis accouplées, des agneaux nés par rapport aux brebis agnelant (prolificité); des agneaux nés vivants sur les nés totaux, des agneaux sevrés sur les nés vivants, des agneaux sevrés par brebis accouplée, et du kg d'agneau sevré par 100 kg de brebis accouplées étaient 98,3%; 93,5%, 103,1%, 94,9%, 97,8%, 90,0%, 18; 2 kg et 38,4 kg respectivement. Les races natives n'étaient pas différentes pour les autres caractères étudiés excepté pour la prolificité qui était plus élevée en Mehraban qu'en Karakul. Les accouplements en race pure ne différaient pas des croisements pour tous les caractères concernant le nombre d'agneaux mais le croisement améliorait les kg d'agneaux sevrés par 100 kg de brebis accouplée (9,2%P=0,08) et les kg sevrés par 100 kg de brebis accouplée (10,0%P<0,05). Parmi les 3 races natives, la Karakul montrait l'amélioration la plus grande lorsque croisée avec les béliers exotiques pour les caractères concernant les kg d'agneaux sevrés. Les béliers Corriedale et Targhee avaient des effets similaires sur tous les caractères étudiés. Un plus faible pourcentage de brebis vierges à oestrus visible, avait un plus faible taux de jumeaux et de productivité comparé aux brebis matures. Le sexe n'était pas une source significative de variation dans la viabilité des agneaux.相似文献
69.
Abstract. Experiments were started in 1967 to investigate the effects of soil mixing on fen peat soil. Peaty topsoil was mixed with mineral subsoil to a maximum depth of 80 cm at two sites, one with a clay subsoil, the other sand. Mixing was done on a commercial scale with a range of implements. After initial increases, yields of arable crops on both mixed soils were subsequently similar to those on unmixed soil. Residual herbicide activity was enhanced on mixed soils, and evidence of peat conservation was obtained at one site. The practice has not been taken up commercially because of the high capital cost of mixing and lack of serious problems which had been predicted following peat wastage. 相似文献
70.