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91.
An apocrine adenocarcinoma was observed in the subcutis of the abdomen of golden hamster. Histologically, the tumor cells irregularly formed multiple layers of cysts and some detached cells were presented in the cystic space. PAS stain with alpha-amylase digestion revealed PAS-positive alpha-amylase-resistant granules in the cytoplasm. Immunohistochemically, cytokeratin was demonstrated in the tumor cells. By electron microscopy, the tumor cells had an oval nucleus with invagination, abundant cytoplasmic organelles and microvilli protruding into the intercellular spaces.  相似文献   
92.
Xylazine (0.2 mg/kg, iv) alone or preceded by atipame-zole (0.125 μg/kg, iv) or by aspirin (10 μg/kg, iv) was administered to 18 sheep. Medetomidine (60 μg/kg, iv) was also administered to 12 sheep. Xylazine, but not medetomidine, significantly reduced the number of platelets. Both atipamezole and aspirin prevented this reduction. It was concluded that α2-agonists would seem to produce platelet aggregation that may contribute to the development of the respiratory changes that follow the administration of α2-agonists in sheep, but probably not always to a degree that could result in a significant decrease in the number of circulating platelets.  相似文献   
93.
Abstract. Leaching losses of nitrate-nitrogen were measured from a set of eight hydrologically isolated plots on a clay loam soil over the period from September 1987 to February 1990. Variable drainflow recovery from the plots hampered accurate estimation of nitrate loading, but results suggest that, when inorganic nitrogen fertilizer is applied up to the recommended amount, there is little influence of the amount applied on the amount leached. We did, however, observe the following effects on nitrate leaching: leguminous green manure incorporated in autumn increased leaching of nitrate-nitrogen by 10–15 kg per hectare during the winter; autumn cultivation caused some increase in leaching compared with no cultivation in one year; some systematic variations in nitrate leaching occurred between years and between plots, but were unrelated to treatments.
From the results we conclude that green manuring does not provide sufficient nitrogen for organically grown crops on this soil but contributes significantly to nitrate leaching, and that growing spring cereals, with the land remaining in stubble as long as possible in autumn, may be the best strategy to minimize nitrate leaching.  相似文献   
94.
95.
Bluetongue virus (BTV), an arthropod-borne virus, is transmitted primarily by biting midges of the genus Culicoides. Some insect species, which might serve as a potential vector, are prevalent in Central Europe. In sheep, bluetongue is acute and mortality is high, whereas in cattle, goats and most wild ruminants the infection is usually clinically inapparent. Viremia is of short duration in sheep, but cattle experience a prolonged viremia and provide a reservoir for the dissemination of BTV. At least 24 different BTV serotypes have been identified. Antigenic variations occur in the polypeptides of the outer viral capsid and the segmented nature of the viral genome provides the potential for evolution of the virus by a mechanism of reassortment. This renders the use of polyvalent vaccines inefficient and emphasizes the significance of import/export restrictions on ruminants from BTV endemic areas.  相似文献   
96.
The technique of cystocentesis in dogs and cats was studied. The indications and contraindications of this method are discussed, using illustrations.  相似文献   
97.
Digital diseases are commonly seen in cattle. Cattle affected by digital disorders do not always respond to conservative therapy and require surgery. Surgical procedures for the common digital disorders are described, with emphasis on the different approaches to the distal interphalangeal joint.  相似文献   
98.
Summary The potential for increased productivity of N'Dama cattle in response to small supplementary inputs of proteinaceous by-products has been shown to be substantial under village husbandry conditions in The Gambia. Young N'Dama bulls were used to compare sesame cake with cottonseed as sources of supplementary protein during the wet and early dry seasons of 1987. They were fed 0, 40, 80 or 160 g crude protein/day in these forms for four months. Supplementation significantly increased growth rate from 169 g/d in controls to means of 272 and 271 g/d for those given sesame cake and cottonseed respectively; there were no significant differences among the supplemented groups. During the four months of the dry season immediately after supplementation ceased all previously supplemented groups grew significantly more rapidly than the controls (at leastP<0·05), indicating a substantial carry over effect of the supplements. Over this period the mean gain of the groups previously given sesame cake exceeded that of those that had received cottonseed (217 cf. 158 g/d;P<0·01). The economic benefits of these responses were substantial.
Comparacion de torta de sesamo y de semilla de algodon como fuente suplementaria de proteina para terneros destetos N'Dama en Gambia
Resumen Se ha demonstrado el potencial para incrementar la productividad del ganado N'Dama, como resquesta a peque?as cantidades de insumos suplementarios de proteína, bajo condiciones de villorrio en Gambia. Se utilizaron terneros destetos N'Dama par comparar la torta de sésamo y de semilla de algodón como fuente de proteína suplementaria durate la estaicón lluviosa y principio de la seca del a?o 1987. Se les dió a los animales 0, 40, 80 o 160 g de proteína cruda/día en éstas formas durante cuatro meses. La suplementación incrementó significativamente la tasa de crecimiento, de 169 g/día en controles a 272 y 271 g/día en aquellos que recibieron torta de sésamo y de algodón respectivamente; no hubo diferenca estadística entre los grupos suplementados. Durate los cuatro meses de la estación seca inmediatamente después de que la suplementación fue suspendida, todos los grupos que habían sido suplementados crecieron sgnificativamente más rápido que los controls (P<0·05), indicando un efecto compensatorio en los suplementados. Durante ese período la media de crecimento de los grupos que recibieron torta de sésamo excedió a aquella de los que habían recibido torta de algodón (217 cf. 158 g/d;P<0·01). Los beneficios económicos de estos resultados fueron substanciales.

Comparaison entre le tourteau de sesame et la graine de coton comme sources complementaires de proteines pour les taurillons N'Dama sevres en Gambie
Résumé Le potentiel de réponse à de petites quantités supplémentaires de sous-produits proteiniques pour accroitre la productivité de bétail N'Dama, s'est révélé manifeste, dans les conditions d'élevage villageois en Gambie. De jeunes taureaux N'Dama ont été utilisés pour comparer le tourteau de sésame et la graine de coton en tant que source de complémentation protéinique pendant la saison sèche et le début de la saison humide au cours de l'année 1987. Ils ont re?u respectivement 0, 40, 80 ou 160 g de proteines brutes par jour sus ces deux formes pendat quatre mois. Cette supplémentation a accru de fa?on significative le taux de croissance, de 169 g/jour pour les témoins jusqu'à des moyennes de 272 et 271g/jour respectivement pour ceux qui ont re?u du tourteau de sésame et de la graine de coton. Quant aux groupes complémentés, il n'ont révélé aucune différence significative. Pendat les quatre mois de la saison sèche et immédiatement après l'arrêt de la supplémentation, tous les lots ayant fait précédemment l'objet d'une distribution complémentaire ont eu une croissance significativement plus rapide que les animaux témoins, du moins pourP<0,05, ce qui indique un effet important de report des suppléments. Durant cette période, le gain moyen des lots qui ont re?u le tourteau de sésame a dépassé celui des lots auxquels on a donné de la graine de coton, soit 217 g/jour contre 158 g/jour pourP<0,01. Les profits économiques de ces réponses ont été appréciables.
  相似文献   
99.
In a previous study we found a positive correlation between early weaning in calves and morphological parameters which were indicative of ruminal development, i.e. the length and width of the papillae. The objective of the present study was to determine to what extent this observation could be reflected by modulations of absorptive and secretory functions of the rumen mucosa. For this purpose the short-circuit currents (Isc) as a measure of electrogenic net ion fluxes and the transepithelial conductances (G(T)) as a measure of the overall tissue permeability were measured in vitro applying the Ussing-chamber technique. Simultaneously, the unidirectional flux rates of sodium and chloride across rumen wall epithelia were determined in the absence of electrochemical gradients. Under these conditions, significant positive net flux rates (Jnet) clearly indicate active mechanisms for electrolyte absorption. For the experiments 12 male Holstein calves 7 d of age were assigned to three groups of 4 animals each: milk group (I, slaughtered after 6 weeks of age), late weaning group (II, slaughtered after 9 weeks of age) and early weaning group (II, weaned after 6 weeks of age and slaughtered after 9 weeks of age). Whereas G(T) values remained unaffected by different age and feeding, Isc values were significantly affected by early weaning but were not influenced by age. Irrespective of weaning time active absorption of Na+ tended to be higher by about 60% in 9 weeks old animals. Active absorption of chloride was significantly increased in milk fed 9 weeke old calves and this effect was further stimulated by early weaning. In conclusion, the data show an increasing active Na+ absorption with age in calf rumen that could not be influenced by early weaning. Similarly, active Cl- absorption was initially increased during postnatal development and this effect could be stimulated further by early weaning.  相似文献   
100.
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