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Four mares fed a low fiber, high soluble carbohydrate diet were used in a crossover design to evaluate the effects of dietary sodium bicarbonate (NaHCO3) supplementation during daily low-intensity submaximal working conditions. Mares were fed the diet at 1.7 times the maintenance energy requirement for mature horses at work. The horses tolerated the diet well and had no clinical abnormalities. Resting venous blood bicarbonate (HCO3), standard HCO3, and base excess (BE) concentrations significantly (P less than 0.05) increased with NaHCO3 supplementation, but no significant changes in resting venous blood pH or carbon dioxide tension (PCO2) were recorded. Venous blood HCO3, standard HCO3, BE, hemoglobin, and heart rate were significantly (P less than 0.05) increased and plasma lactate concentration was significantly (P less than 0.05) decreased in the control horses and in the horses given the NaHCO3 supplement during low-intensity submaximal exercise. There were no significant changes in venous blood pH, PCO2, or plasma protein concentration with exercise. Venous blood HCO3, standard HCO3, and BE concentrations were significantly (P less than 0.05) greater during submaximal exercise in horses given the NaHCO3 supplement. There were no significant differences in plasma lactate or total protein concentrations, blood pH, PCO2, or hemoglobin concentration between the 2 groups during exercise.  相似文献   
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Immunization against cholecystokinin decreases appetite in lambs.   总被引:1,自引:0,他引:1  
The effects of immunization against cholecystokinin (CCK) on feed intake, weight gain, and carcass characteristics were studied in sheep. Nine wether lambs at 10 wk of age were immunized with a conjugate of sulphated CCK octapeptide and human serum globulin or against human globulin alone. All CCK-immunized lambs produced antibodies, and the average titer 5 wk after the primary immunization was calculated to be sufficient to bind normal circulating levels of CCK. Mean daily feed intakes and BW were similar in the CCK-immunized and the control-immunized groups at the start of treatment, but after immunization, feed intake, appetite, and BW gain were decreased in the CCK-immunized animals. There was no effect on carcass composition or organ growth relative to body growth. It is concluded that the immunization procedure used in this study may have potentiated the actions of CCK rather than neutralizing its action as an appetite regulator.  相似文献   
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Resistance of gram-negative bacteria to gentamicin has become an increasingly common problem among clinical isolates from human beings. Susceptibility of isolates from horses to gentamicin and amikacin was evaluated for the period from July, 1983 to June, 1985. All isolates of Escherichia coli, and species of Enterobacter, Klebsiella, Proteus, and Pseudomonas examined were susceptible to amikacin, except 2 of the 46 Pseudomonas isolates. In contrast, 13 to 50% of isolates were resistant to gentamicin. Escherichia coli, and Klebsiella, Proteus, and Enterobacter species isolates were highly significantly more susceptible to amikacin (P less than 0.01) than to gentamicin. Pseudomonas spp (P = 0.13) were not significantly different in susceptibility to the 2 drugs. There was significant variation among genera in their susceptibility to gentamicin (P = 0.002), primarily because of the frequency of resistance in isolates of Klebsiella spp and Proteus spp, compared with the other 3 organisms (E coli, Enterobacter spp, and Pseudomonas spp). There was no significant difference of susceptibility to amikacin among the genera studied (P = 0.06).  相似文献   
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AIM: To assess the benefit of inducing emesis in dogs that have ingested rodenticide bait containing brodifacoum (BDF), by determining the amount of BDF in bait recovered from the vomitus relative to the estimated amount consumed.

METHODS: Between 2014 and 2015 samples of vomitus from seven dogs that ingested rodenticide baits containing BDF were submitted by veterinarians in New Zealand. All seven dogs had been given apomorphine by the veterinarian and vomited within 1 hour of ingesting the bait. Some or all of the bait particles were retrieved from each sample and were analysed for concentrations of BDF using HPLC. Based on estimations of the mass of bait consumed, the concentration of BDF stated on the product label, and the estimated mass of bait in the vomitus of each dog, the amount of BDF in the vomited bait was calculated as a percentage of the amount ingested.

RESULTS: For five dogs an estimation of the mass of bait ingested was provided by the submitting veterinarian. For these dogs the estimated percentage of BDF in the bait retrieved from the vomitus was between 10–77%. All dogs were well after discharge but only one dog returned for further testing. This dog had a normal prothrombin time 3 days after ingestion.

CONCLUSIONS AND CLINICAL RELEVANCE: The induction of emesis within 1 hour of ingestion can be a useful tool in reducing the exposure of dogs to a toxic dose of BDF. The BDF was not fully absorbed within 1 hour of ingestion suggesting that the early induction of emesis can remove bait containing BDF before it can be fully absorbed.  相似文献   

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Zoledronate is a bisphosphonate frequently used for the treatment of hypercalcaemia of malignancy and tumour-associated bone pain in dogs, however, there is a paucity of information regarding its use in veterinary medicine. The aim of this retrospective study was to report the tolerability of zoledronate in the palliative treatment of cancer-bearing dogs and secondarily to to assess the efficacy of zoledronate for the treatment of hypercalcaemia of malignancy. Thirty-seven dogs (22 with tumour-associated bone pain and 15 with hypercalcaemia of malignancy) that received 114 zoledronate infusions were included. Tolerability was assessed by the absence of post-zoledronate hypocalcaemia or other adverse events as defined by Veterinary Cooperative Oncology Group-Common Terminology Criteria for Adverse Events criteria. Efficacy was assessed by comparison of available ionized calcium levels before and after zoledronate administration in hypercalcaemic dogs. In 79% of zoledronate infusions, no adverse events were reported. The majority of adverse events which occurred in the other 21% of infusions could be attributed to concurrent chemotherapy or the underlying neoplastic disease. There was a small but significant increase in creatinine following treatment with zoledronate, however, none of the dogs developed clinically significant renal disease. In eight hypercalcaemic dogs with available ionized calcium following zoledronate administration, ionized calcium decreased rapidly within 7 days following treatment with zoledronate. Zoledronate is well-tolerated with few recorded adverse events, however, monitoring of serum creatinine is advised. Zoledronate seems to be effective in the treatment of hypercalcaemia of malignancy.  相似文献   
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Summary The development of the sclerotia (black scurf) ofRhizoctonia solani Kühn, on potato tubers is related to tuber maturity and the health of the root and stolon systems. Few sclerotia formed on tubers from untreated plants until the onset of plant senescence when, as the tubers matured and roots and stolons decayed, sclerotia developed both rapidly and extensively. Application of acid to haulms in early August led to an increase in black scurf on tubers, initially related to the increase in root and stolon infection, but especially after later harvests, to the degree of tuber maturity. Later in August, scurf increases were paralleled both by tuber changes and root and stolon infection. My mid-September, when acid application was to plants becoming senescent, there was little difference between patterns of infection found on treated and check plants.
Zusammenfassung In diesem Artikel wird der Fortlauf der Infektion durchRhizoctonia solani Kühn an Wurzeln. Stolonen und Knollen beschrieben. Ferner wird der Einfluss der Krautvernichtung und des zeitlichen Abstandes zwischen ihr und der Ernte auf diese Infektion untersucht. Pflanzknollen der Sorte Majestic wurden am Kronenende direkt vor dem Auspflanzen mit vier Isolaten vonR. solani (aus Sklerotien von Kartoffelknollen) inokuliert. An den ausgelesenen Knollen war keine Pockenkrankheit sichtbar. Das Kraut wurde an einem von fünf Daten gespritzt resp, nicht gespritzt und die Pflanzen nachher in Intervallen geerntet (Tabelle 1). Wurzel- und Stolonenteile wurden gewaschen, dann auf Leitungswasseragar, das 50 mg Neomycin und Chloramphenicol proliter enthielt, gebracht und vor der Beurteilung auf Rhizoctoniabefall w?hrend 48 Stunden bei Zimmertemperatur bebrütet. Die Pflanzknollen wurden gem?ss Tabelle 2 auf Sklerotienbefall beurteilt. Zur Reifesch?tzung wurde jede Knolle der L?nge nach geschnitten und der Prozentsatz des Periderms notiert, das mit einer Pinzette entfernt werden konnte, wenn man am Kronenende begann. Die Kontrollpflanzen hatten bis Mitte September bei nur beschr?nkter lokaler Infektion durchR. solani (Abb. 1 und 2) relativ gesunde Untergrundsysteme. In den folgenden drei Wochen reiften die Knollenperiderme. Wurzeln und Stolonen wurden weitgehend vom Pilz besiedelt. Folglich ?nderte sich die N?hrstoffversorgung des Pilzes, eine Situation, von der man weiss, dass sie die Entwicklung zur Sklerotienbildung f?rdert. Mitte September widerspiegelt sich die ?nderung in der Ern?hrung in einem Ansteigen der Anzahl von Knollen mit Pocken und in deren Ausdehnung auf den Knollen (Abb. 3 und 4). Krautvernichtung mit S?ure Anfang August führte zu einer Zunahme der Pockenkrankheit, was anf?nglich auf eine Zunahme der Wurzel- und Stoloneninfektion, sp?ter aber auf den Grad der Knollenreife (Abb. 5) in Beziehung stand.: Sp?ter, im August, wurden die Krankheitszunahmen mit Knollen?nderungen wie mit Wurzel- und Stoloneninfektion gleichlaufend. Die S?ureanwendung Mitte September geschah an alternden Pflanzen und ?nderte das an Kontrollpflanzen beobachtete Infektionsbild wenig.

Résumé Cet article décrit l'évolution de la contamination, parRhizoctonia solani Kühn, des racines, stolons et tubercules de pommes de terre, et examine l'influence du défanage et de l'intervalle défanagerécolté sur une telle contamination. Des tubercules de la variété Majestic n'étant pas visuellement porteurs de sclérotes ont été inoculés à la couronne, juste avant la plantation, avec 4 souches deR. solani provenant de sclérotes sur tubercules de pommes de terre. Les tiges ont été ou n'ont pas été défanées à 5 dates différentes et on a récolté ensuite les tubercules à intervalles réguliers (tableau 1). Les fragments de racines et de stolons ont été lavés, placés sur une gelose à l'eau du robinet, contenant 50 mg de néomycin et de chloramphénicol par litre, et mis à incuber 48 heures à température ambiante avant notation de l'infection parR. solani. La notation des sclérotes sur tuberculesfils a été effectuée comme cela est indiqué dans le tableau 2. Comme estimation de la ‘maturité’ chaque tubercule a été coupé selon l'axe longitudinal et on a noté le pourcentage de périderme, en partant de la couronne qui a pu être enlevé avec des pinces. Les plantes témoins ont eu leurs systémes souterrains relativement sains jusqu'à la mi-septembre avec des contaminations locales parR. solani, limitées (figures 1 & 2). Les trois semaines suivantes, la maturité des tubercules a augmenté et les racines et stolons ont été fortement contaminés par le champignon. Le support nutritionnel du champignon a donc été altéré, cet élément connu permet de stimuler la maturité des sclérotes en cours de formation. Vers la mi-septembre, des changements nutritionnels se sont soldés par une augmentation du nombre de tubercules porteurs de sclérotes et par l'extension de ces derniers (figures 3 & 4). Le défanage aux colorants nitrés début ao?t a entrainé une augmentation des sclérotes, qui s'était manifestée initialement par une augmentation de la contamination des racines et stolons, et plus tard au niveau du degré de maturité du tubercule (figure 5). Plus tardivement en ao?t, l'augmentation des sclérotes allait de paire avec le changement de tubercule et avec la contamination des racines et stolons. Vers la mi-septembre, le défanage sur des plantes proches de la senescence a eu un léger effet sur la contamination des plantes témoins.
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