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1.
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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The Mexican cichlid Cichlasoma beani is currently exploited regionally as food and can be commercialized in the aquarium trade. Natural populations of C. beani may already be negatively affected by anthropogenic alteration of the areas in which it is distributed. The aim of the present study was to examine the effect on growth, survival, and condition of C. beani cultured in three stocking densities: three (D3), six (D6), and nine (D9) fish per each 40 L tank. At the end of a 6‐wk trial the fish cultured in D3 were longer, heavier, and grew faster than the rest of the treatments but their survival was the lowest compared to D6 and D9. The mortalities were caused by a strong aggressive behavior in D3.  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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Drought is ubiquitous in rainfed cropping systems and often limits maize yields. The sensitivity of transpiration response early in progressive soil drying is a trait with potential to improve crop drought resistance. Simulation studies demonstrated that increased sensitivity to drying soil leading to restricted transpiration rates results in conservation of soil water during vegetative stages for possible use during grain filling. In contrast to other crops, there have been no studies characterizing genotypic variability for this trait in maize. Experiments in controlled environments were conducted to characterize the fraction of transpirable soil water (FTSW) threshold on drying soil for 36 hybrids selected for variation in the field for drought resistance, regions of adaptation and stay green. While FTSW thresholds varied among hybrids from 0.60 to 0.33, these thresholds were not uniformly associated with level of drought resistance in the field. Nevertheless, this study demonstrated a high FTSW threshold corresponded with drought resistance observed in some modern maize germplasm (hybrids #7, 17, 24, 27 and 32). This knowledge can enable breeding work seeking to exploit this adaptive trait to improved drought tolerance in low threshold FTSW germplasm.  相似文献   
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Activities associated with timber harvesting have occurred within floodplain forests in the southern United States for nearly two hundred years. However, it is only in the last ten years that any information has become available about the effects of harvesting on the ecological functions of this valuable resource. Hydrology is the driving influence behind all ecological processes in floodplains, and timber harvesting alone usually has little long-term effect on hydroperiod. However, logging roads, built in association with harvest sites, can sometimes alter hydroperiod to the extent that vegetation productivity is raised or lowered. There is no evidence that harvesting followed by natural regeneration represents a threat to ground or surface water quality on flood plain sites, as long as “best management practices” are followed. Harvested floodplains may increase or have little effect on decomposition rates of surface organic matter. The nature of the effect seems to be controlled by site wetness. Data from recently harvested sites (i.e. within the last ten years) suggest that vegetation productivity is maintained at levels similar to those observed prior to harvests. During the early stages of stand development, tree species composition is heavily influenced by harvest method. Similarly, amphibian populations (monitored as bioindicators of ecosystem recovery) seem to rebound rapidly following harvests, although species composition may be different from that of unharvested stands.  相似文献   
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We studied diurnal changes in water conduction during soil dehydration in 37-month-old seedlings of one Virginia pine (Pinus virginiana Mill.) and two loblolly pine (P. taeda L.) sources, one from North Carolina (NC) and the other from the "Lost Pines" areas of Texas (TX), in an environmentally controlled growth chamber. For seedlings of similar biomass, the TX source had higher values of transpiration, needle conductance, and plant hydraulic conductivity under well-watered conditions than the NC source. Under dry soil conditions, the TX source had lower values of water conduction than the NC source. The Virginia pine source responded similarly to the TX source under both well-watered and dry soil conditions. For all three pine sources, gradients between soil and needle water potentials were greatest when the seedlings were moderately stressed. The TX and Virginia pine sources had higher gradients and lower daytime needle water potentials under moderate stress conditions than the NC source. Predawn needle water potentials did not differ among the pine sources. We conclude that the TX and Virginia pine sources have decreased daytime needle water potentials and increased water potential gradients during the daytime under moderate stress conditions, but with no disruption of recovery at predawn. The greater rates of transpiration and water conduction by the TX source compared with the NC source under well-watered conditions suggest a means by which growth can be maximized prior to the onset of drought, thereby enhancing survival of loblolly pines in drought-prone environments.  相似文献   
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The study compared response to prostaglandin F2α (PG), synchrony of ovulation and pregnancy per AI (P/AI) in a 5‐ vs a 7‐day Ovsynch + PRID protocol and investigated whether the initial GnRH affects P/AI in lactating dairy cows. Two hundred and seventy‐six cows (500 inseminations) were assigned to one of four timed‐AI (TAI) protocols: (i) PRID‐7G; 100 μg GnRH im, and a progesterone‐releasing intravaginal device (PRID) for 7 days. At PRID removal, PG (500 μg of cloprostenol) was given im. Cows received the second GnRH treatment at 60 h after PRID removal and TAI 12 h later. (ii) PRID‐5G; as PRID‐7G except the duration of PRID, treatment was 5 days and PG was given twice (12 h apart). (iii) PRID‐7NoG; as PRID‐7G except the initial GnRH, treatment was omitted. (iv) PRID‐5NoG; as PRID‐7NoG except the duration of PRID, treatment was 5 days. Response to treatments and pregnancy status at 32 and 60 days after TAI was determined by ultrasonography. The percentage of cows ovulating before TAI was greatest in PRID‐7G (17.1%), and the percentage of cows that did not have luteal regression was greatest in PRID‐5G (9.5%). The overall P/AI at 32 and 60 days did not differ among TAI protocols. However, during resynchronization, cows subjected to the 5‐day protocols had greater (p < 0.05) P/AI (45.3% vs 33.6%) than cows subjected to the 7‐day protocols. Pregnancy loss between 32 and 60 days tended (p = 0.10) to be greater in cows that did not receive initial GnRH (14.8%) compared to those that received GnRH (8.2%). In conclusion, the PRID‐5G protocol resulted in fewer cows responding to PG, but P/AI did not differ among TAI protocols. A 5‐day protocol resulted in more P/AI in resynchronized cows, and cows that did not receive initial GnRH tended to experience more pregnancy losses.  相似文献   
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