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51.
M. L. Macpherson S. Giguère M. A. Pozor E. Runcan T. W. Vickroy S. A. Benson M. H. T. Troedsson J. N. Hatzel J. Larson E. vanden Berg A. A. Kelleman L. C. Sanchez M. M. LeBlanc 《Journal of veterinary pharmacology and therapeutics》2017,40(6):656-662
Eleven pregnant pony mares (D270‐326) were administered ceftiofur sodium intramuscularly at 2.2 mg/kg (n = 6) or 4.4 mg/kg (n = 5), once daily. Plasma was obtained prior to ceftiofur administration and at 0.5, 1, 2, 4, 8, 12, and 24 hr after administration. Eight pony mares were re‐enrolled in the study at least 3 days from expected foaling to ensure steady‐state concentrations of drug at the time of foaling. Mares were administered ceftiofur sodium (4.4 mg/kg, IM) daily until foaling. Parturition was induced using oxytocin 1 hr after ceftiofur sodium administration. Allantoic and amniotic fluid, plasma, and colostrum samples were collected at time of foaling. Serial foal plasma samples were obtained. Placental tissues were collected. Desfuroylceftiofur acetamide (DCA) concentrations were measured in samples by high‐performance liquid chromatography (HPLC). Mean (±SD) peak serum concentrations of DCA were 3.97 ± 0.50 μg/ml (low dose) and 7.45 ± 1.05 μg/ml (high dose). Terminal half‐life was significantly (p = .014) shorter after administration of the low dose (2.91 ± 0.59 hr) than after administration of the high dose (4.10 ± 0.72 hr). The mean serum concentration of DCA from mares at time of foaling was 7.96 ± 1.39 μg/ml. The mean DCA concentration in colostrum was 1.39 ± 0.70 μg/ml. DCA concentrations in allantoic fluid, amniotic fluid, placental tissues, and foal plasma were below the limit of quantification (<0.1 μg/ml) and below the minimum inhibitory concentration of ceftiofur against relevant pathogens. These results infer incomplete passage of DCA across fetal membranes after administration of ceftiofur sodium to normal pony mares. 相似文献
52.
A successful method for low temperature preservation of bull semen was modified for use with boar semen. Observations were made on the effects of varying cooling rate, equilibration time, freezing rate, glycerol concentration, method of glycerol addition, packaging containers, extender pH and tonicity. Observations indicate that boar semen should be cooled and frozen at a slower rate than bull semen. Within the ranges or methods examined, the other factors had little effect on recovery of motility after freezing. 相似文献
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54.
A biometrical study of female porcine reproductive tracts recovered after slaughter was carried out. Sizes and weights of the various areas from one hundred eighty-seven sow tracts, eighty-one pre-puberal gilts and thirty-two puberal gilts were recorded. A table of abnormalities observed in examination of the sow tracts is also presented. 相似文献
55.
Alkaline phosphatase activity was recorded in forty ejaculates of the sperm rich fraction of boar semen as 9,790 ± 5,250 Klein-Babson-Read units per 100 ml. of seminal plasma. Acid phosphatase activity in the same ejaculates was 681 ± 304 Babson-Read units per 100 ml. of seminal plasma. No alkaline phosphatase activity was detected in the seminal plasma of vasectomized boars.
The pH of the sperm rich fractions was 7.69 ± 0.33 and the osmotic pressure was 313.56 ± 7.98 milliosmols.
相似文献56.
A mature male alpaca with acute lameness of the left handlimb was diagnosed as having a rupture of the cranial cruciate ligament. Repair was achieved using a combination of surgical techniques. A patellar ligament autograft was passed under the cranial meniscal ligament, through the joint and over the femoral condyle, and anchored using a screw and washer. Two nylon sutures were passed through a hole made in the tibial crest, and secured under the screw. The alpaca was confined in a stall for 3 months. Exercise was then increased progressively for 3 months. One year after surgery the alpaca is sound and has resumed breeding activity. 相似文献
57.
MA Beswick N Choi CN Harmer AD Hopkins M McPartlin DS Wright 《Science (New York, N.Y.)》1998,281(5382):1500-1501
Thermolysis of the heterobimetallic phosphinidene complex [Sb(PCy)3]2- Li6.6HNMe2 (Cy = C6H11) at 303 to 313 kelvin gives Zintl compounds containing (Sb7)3- anions. The complex thus constitutes a stable molecular single-source precursor to Zintl compounds and provides a potential low-temperature route to photoactive alkali metal antimonates. The new chemical reaction involved, which is driven thermodynamically by the formation of P-P bonds, has implications in the low-temperature synthesis of other technologically important materials (such as gallium arsenide). 相似文献
58.
While ‘solutions’ to challenges of water supply in the Pacific may seem obvious to hydrologists, engineers and planners, their implementation may not be straightforward. Water is embedded in cultural, religious and political contexts, and what seems obvious to planners may seem neither obvious, nor acceptable, to citizens. However, these contexts change continuously, and opportunities arise for changes in narratives around ownership, supply and management of water. Citizens' beliefs about the state's ‘rights’ will vary with societal context, and will shape the ways in which ownership and management of water is worked out in specific locations. This paper outlines thinking and discourses around ownership and management of fresh water in Samoa, and the constraints which culture has imposed on water supply over time. Water discourses have shifted from questions about ownership of specific sources to general discussions about conservation and management of natural resources. This shift has resulted, in part, from the ways in which government has managed the process and, in part, from growing public awareness of water within the larger environmental context. The paper focuses on Samoan material, but some of the generic issues have wider significance in the Pacific because similar variables combine in similar ways. 相似文献
59.
60.
A micro-method is described by which as little as 10gamma of specific precipitate nitrogen may be determined with a fair degree of accuracy. The error in repeated determinations is about +/- 2gamma. 相似文献