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BACKGROUND

Aerial treatments for invasive species management are now common, but we are unaware of any work published in the scientific literature quantifying how the interplay of numerous factors affects flight time and therefore operational costs. Here, we analyse aerial treatment data collected from two ant-eradication programmes, quantifying how the relationships between flight time and area are influenced by numerous aircraft/delivery system/bait/flight speed combinations.

RESULTS

For bait dispersal by helicopters, and when swath widths are equivalent, side-mounted Isolair was significantly more efficient than the simultaneous use of two underslung buckets, and use of two buckets was slightly but not significantly more efficient than one bucket. In this scenario, delivery by Isolair was, on average, 39.8% and 31.5% more efficient than the use of one or two buckets, respectively. However, when the swath width used with Isolair was halved to 10 m and flight speed was increased slightly, flight time was significantly greater compared to the other configurations. For bait dispersed by drone, flights conducted using an upgraded Flight Management System (FMS) and greater flight speed but smaller swath width were significantly more efficient than flights using the older FMS and lower flight speed. Over 10 and 50 ha the helicopter was 2.87 and 4.82 times more time efficient than the drone.

CONCLUSION

We encourage practitioners to publish data from their aerial treatments, and to try new methods, to accelerate improvements in efficiency and reduce the costs of aerial treatments. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
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AIMS: To record the prevalence of gross abnormalities of the reproductive tract in culled New Zealand dairy cows, to determine how accurately farmers classify the pregnancy status of their animals and to establish if this was influenced by method of pregnancy diagnosis. METHODS: The reproductive tracts from 1134 cull dairy cows were examined after slaughter and evisceration for the presence of gross abnormalities, ovarian activity and pregnancy at a commercial abattoir. The farmers that had submitted these animals for slaughter were surveyed for information about the farm and herd from which each cow was derived and to establish whether the farmer believed each cow to be pregnant or not. The method that had been used to determine pregnancy status was recorded for each animal. RESULTS: Gross abnormalities were evident in 5.7% of reproductive tracts. Ovarian activity (presence of follicles 5 mm diameter and/or a corpus luteum) was apparent in 88% of non-pregnant cows. Pregnancy was detected in 39% of cows, of which 2.3% carried twins. The pregnancy status evident at slaughter varied from that reported by farmers in 7.0% of the 954 cows for which farmers were able to provide information. Of the cows that had been examined by palpation or ultrasound per rectum prior to slaughter, 10.3% that were recorded as non-pregnant by farmers were pregnant, and 3.2% of those recorded as pregnant were not. Of the cows that had not been examined, 3.8% of those recorded as nonpregnant by farmers were pregnant while 10.4% of those recorded as pregnant were not. There was no apparent association between gross genital tract abnormalities or ovarian activity and the misclassification of pregnancy status. Amongst cows that were pregnant at slaughter the foetus was significantly smaller in cows that had been recorded as 'not pregnant' after palpation or ultrasound examination than in cows that had been recorded as 'not pregnant' on the basis of farmer observation only. CONCLUSIONS: The prevalence of gross abnormalities of the reproductive tract was comparable to that reported in similar studies overseas. Farmer observation as a method of pregnancy detection overestimates pregnancy rate. Pregnancy status may be misclassified or misrecorded following palpation or ultrasound examination of cattle per rectum. Accurate classification of pregnancy status is dependent on the method and timing of pregnancy diagnosis and on minimising errors of diagnosis, cow identification and recording.  相似文献   
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含莫纳可林K红曲降低鸡蛋胆固醇效果的研究   总被引:1,自引:0,他引:1  
48只68周龄的海兰褐蛋鸡分成三组,按0.5%和10%比例分别添加含0.4%莫纳可林K红曲于各组日粮内,饲喂22d,观测其对鸡蛋胆固醇变化的影响。结果表明,投药后5—6d,10%添加组和5%添加组蛋黄胆固醇开始下降;15—22d的胆固醇含量与1~5d相比,10%添加组和5%添加组分别下降了9.02%和5.10%,而对照组升高了5.22%。  相似文献   
6.
氧氟沙星药物的研究进展   总被引:2,自引:0,他引:2  
通过对氧氟沙星药物近十年来的检测方法、药代动力学、药效学、耐药性及抗菌后效应、联合应用及毒理学、残留及残留的检测方法等六个方面的大量研究资料进行综述,详细介绍并论述了氧氟沙星药物在这些方面的最新研究成果,对氧氟沙星药物及其他喹诺酮类药物的进一步研究、开发和应用具有指导意义。  相似文献   
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Objective Correlation of immunophenotype with history, anatomical and morphological features of lymphoid neoplasia in the koala.
Methods Routine necropsies were performed on 51 koalas with suspected lymphoid neoplasia between 1986 and 1997 in New South Wales and Queensland. Immuno-phenotyping was by an immunoperoxidase method utilising species cross-reactive antibodies raised against human lymphocytes and an antibody raised against koala IgG. Cases were classified according to organs and tissues affected and the morphological features of neoplastic cells.
Results Twenty-six (51%) of the cases were of the T cell immunophenotype, 12 (24%) were of B cell immunopheno-type and 13 (25%) did not stain. The age and sex of koalas did not correlate with immunophenotype (P = 0.686 and P = 1.000, respectively). Thirty-two cases were leukaemic and 36 had multiple organ involvement, probably reflecting presenta tion of koalas at advanced stages of disease. Abdominal tissue involvement was most common (44 cases), followed by nodal (32), atypical (21) and cervicomediastinal (14). The T cell immunophenotype was over-represented among the leukaemic cases (P = 0.013). Generally, the T cell immunophenotype predominated except for many affected atypical tissues. Neoplastic cells were mostly of medium nuclear size with round to oval nuclei. No correlations were found for cell morphology, mitotic index and immunopheno-type.
Conclusion The prognostic value of an immunopheno-typic, anatomical and morphological basis for the classifica tion of lymphoid neoplasia in the koala currently is limited by the need to detect these neoplasms at an early age, the requirement for freshly fixed tissues and the restricted range of available cross-reacting antibodies.  相似文献   
9.
Objective To describe a case of diabetes mellitus in a koala (Phascolarctos cinereus).
Design A case report with controls.
Procedures We describe clinical and laboratory findings in a 6-year-old, free-living, female koala presented with traumatic injury and subsequently found to have polydipsia, hyperglycaemia and glucosuria. Over a 5 week period, serum biochemical analyses, haematological examinations, urinal-yses, measurement of serum insulin and fructosamine concentrations, necropsy, histopathological examination of a range of tissues and immunohistochemical examination of the pancreas for insulin-containing cells were done. For reference purposes, serum insulin and fructosamine concentrations were determined in four and two healthy koalas, respectively, and three healthy koalas pancreases were examined histo-logically and immunohistochemically.
Results The koala had persistent hyperglycaemia, hyperlipidaemia, hyponatraemia, hypochloraemia and glucosuria. Serum insulin concentration of the diabetic koala was only marginally smaller than that of healthy koalas, but all concentrations were smaller than reference concentrations in dogs and people. Fructosamine concentration did not allow the diabetic koala to be distinguished from healthy koalas and concentrations of all koala analytes were greater than expected for healthy dogs and people. Histopathological examination revealed extensive degeneration of pancreatic islet cells and fatty infiltration of hepatocytes. Immunoperoxidase staining revealed decreased or absent insulin in the b cells of the affected koala.
Conclusion Clinical signs, clinicopathological results and histopathological changes were consistent with diabetes mellitus. The pathogenesis of the condition could not be determined but may have been related to the administration of a parenteral corticosteroid preparation, the stress of capture or tissue damage and inflammation.  相似文献   
10.
A single dose of 5 x 10(8) bacilli of Pseudomonas pseudomallei by intratracheal injection resulted in acute (21 cases) or chronic (19 cases) melioidosis in 40 of 48 pigs. Fifteen (10 acute and 5 chronic) had been immunosuppressed by cyclophosphamide before inoculation. The major clinical signs were initial fever, marked neutrophilia and, in the acute cases, respiratory distress. There were no signs of the nasal and ocular discharge, paresis or diarrhoea seen in acute cases in south-east Asia. The cyclophosphamide treatment caused a significant decrease in the neutrophil count by 7 d after inoculation in all 15 immunosuppressed pigs, and all were culture positive at necropsy. Eight of the 33 non-treated pigs were culture negative at necropsy. Pigs overcoming the initial phase of infection had more abscess-like nodules that were bacteriologically sterile at necropsy than the pigs with acute cases of melioidosis. P. pseudomallei was isolated predominantly from the spleen, lungs and the injection site. Although only one strain was used in this study, it is likely that Australian strains of P. pseudomallei are not as virulent as the south-east Asian isolates.  相似文献   
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