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81.
Bertram HC Yde CC Zhang X Kristensen NB 《Journal of agricultural and food chemistry》2011,59(23):12499-12505
NMR-based metabolomics was applied on urine samples from 32 cows that were fed four levels of crude protein (124, 135, 151, and 166 g/kg DM, respectively) in a crossover design with the aim of identifying urinary metabolites related to nitrogen intake and nitrogen efficiency. Principal component analysis (PCA) on selected regions of the obtained (1)H NMR spectra revealed an effect of crude protein intake on NMR signals in the 0.5-3.0 and 5.0-10.0 ppm regions. Partial least-squares (PLS) regressions confirmed a correlation between the NMR metabolite profile and both nitrogen intake and efficiency. The NMR signals that correlated with nitrogen intake and efficiency included urea, hippurate, phenylacetylglutamine, and p-cresol sulfate, which all contributed to the prediction of nitrogen intake and efficiency. Thus, it was not possible to identify a single metabolite that could be used as a marker to predict nitrogen efficiency, and it can be concluded that a wide-ranging urinary metabolite profile is needed to evaluate nitrogen efficiency in ruminants. 相似文献
82.
83.
Cayetano Herrera Mark Williams Joao Encarnação Núria Roura-Pascual Bastian Faulhaber José Antonio Jurado-Rivera Mar Leza 《Pest management science》2023,79(3):1225-1233
BACKGROUND
The yellow-legged hornet (Vespa velutina) is native to Southeast Asia and is an invasive alien species of concern in many countries. More effective management of populations of V. velutina could be achieved through more widespread and intensive monitoring in the field, however current methods are labor intensive and costly. To address this issue, we have assessed the performance of an optical sensor combined with a machine learning model to classify V. velutina and native wasps/hornets and bees. Our aim is to use the results of the present work as a step towards the development of a monitoring solution for V. velutina in the field.RESULTS
We recorded a total 935 flights from three bee species: Apis mellifera, Bombus terrestris and Osmia bicornis; and four wasp/hornet species: Polistes dominula, Vespula germanica, Vespa crabro and V. velutina. The machine learning model achieved an average accuracy for species classification of 80.1 ± 13.9% and 74.5 ± 7.0% for V. velutina. V. crabro had the highest level of misclassification, confused mainly with V. velutina and P. dominula. These results were obtained using a 14-value peak and valley feature derived from the wingbeat power spectral density.CONCLUSION
This study demonstrates that the wingbeat recordings from a flying insect sensor can be used with machine learning methods to differentiate V. velutina from six other Hymenoptera species in the laboratory and this knowledge could be used to help develop a tool for use in integrated invasive alien species management programs. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献84.
Objective To assess the toxicity to insects of drug residues excreted in cattle faeces following treatment with deltamethrin.
Design Bioassays were performed on one species of dung-breeding fly ( Musca vetustissima ) and two species of dung beetle ( Onthophagus binodis and Euoniticellus fulvus ).
Animals Cattle on properties near Kangaroo Valley, Canberra and Gundagai were treated with pour-on formulations of deltamethrin. Untreated animals acted as controls.
Procedures Faeces from treated and untreated cattle were inoculated with newly emerged fly larvae or fed to adults of two species of dung beetle. Percentage survival and duration of development provided measures of the toxicity of deltamethrin residues in faeces.
Results Residues of deltamethrin were excreted in concentrations sufficient to inhibit survival of larvae of M vetustissima for 1 to 2 weeks after treatment. Peak concentrations of 0.4mg deltamethrin/kg dry weight of faeces occurred 3 days after treatment and were sufficient to kill adult beetles for at least twice this period. With one of two formulations tested, there was evidence of a reduction in dung beetle fecundity and an increase in the duration of juvenile development. A model of the effect of deltamethrin on the breeding success of dung beetles in the field suggests that a single treatment, applied when most of the population is in a non-parous condition, may cause up to 75% reduction in beetle acitivity by the end of the season. Multiple treatments at 10 or 21 day intervals may drive local populations towards extinction.
Conclusion Depending on the time and frequency of treatment, the effect of deltamethrin on insects in cattle faeces may range from negligible to catastrophic. 相似文献
Design Bioassays were performed on one species of dung-breeding fly ( Musca vetustissima ) and two species of dung beetle ( Onthophagus binodis and Euoniticellus fulvus ).
Animals Cattle on properties near Kangaroo Valley, Canberra and Gundagai were treated with pour-on formulations of deltamethrin. Untreated animals acted as controls.
Procedures Faeces from treated and untreated cattle were inoculated with newly emerged fly larvae or fed to adults of two species of dung beetle. Percentage survival and duration of development provided measures of the toxicity of deltamethrin residues in faeces.
Results Residues of deltamethrin were excreted in concentrations sufficient to inhibit survival of larvae of M vetustissima for 1 to 2 weeks after treatment. Peak concentrations of 0.4mg deltamethrin/kg dry weight of faeces occurred 3 days after treatment and were sufficient to kill adult beetles for at least twice this period. With one of two formulations tested, there was evidence of a reduction in dung beetle fecundity and an increase in the duration of juvenile development. A model of the effect of deltamethrin on the breeding success of dung beetles in the field suggests that a single treatment, applied when most of the population is in a non-parous condition, may cause up to 75% reduction in beetle acitivity by the end of the season. Multiple treatments at 10 or 21 day intervals may drive local populations towards extinction.
Conclusion Depending on the time and frequency of treatment, the effect of deltamethrin on insects in cattle faeces may range from negligible to catastrophic. 相似文献
85.
The system of rice intensification(SRI) is a production system that involves the adoption of certain changes in management practices for rice cultivation that create a better growing environment for the crop.This system was compared with conventional practices and assessed under organic and inorganic management.SRI practices showed significant response in root number,number of effective tillers per hill,days to flowering and harvest index.In addition,SRI was found effective in minimizing pest and disease in... 相似文献
86.
Identification of lactoferrin and glutamate receptor‐interacting protein 1 in bovine cervical mucus: A putative marker for oestrous detection 下载免费PDF全文
WY Lee MH Park KW Kim H Song KB Kim CS Lee NK Kim JK Park BC Yang KB Oh GS Im HJ Chung 《Reproduction in domestic animals》2017,52(1):16-23
Accurate detection of oestrus is important for artificial insemination. The aim of this study was to identify oestrous‐specific bovine cervical mucus proteins that could be used to determine the optimal time for artificial insemination. Non‐oestrous and controlled internal drug release (CIDR)‐induced oestrous‐stage mucus proteins were purified and subjected to surface‐enhanced laser desorption/ionization time‐of‐flight mass spectrometry, sodium dodecyl sulphate polyacrylamide gel electrophoresis and MALDI‐TOF/TOF. Among differentially expressed proteins, lactoferrin (LF) and glutamate receptor‐interacting protein 1 (GRIP1) showed a twofold increase during the CIDR‐induced oestrous stage compared to the levels in non‐oestrous stage in bovine cervical mucus. The RT‐PCR, Western blotting and immunohistochemistry results showed that LF and GRIP1 expression was significantly increased during the oestrous stage in the uterus. This study demonstrated that bovine LF and GRIP1 exist during the oestrous stage, but not during the non‐oestrous stage, suggesting that cervical mucus LF and GRIP1 are useful oestrous detection markers in cattle. 相似文献
87.
BC Schimming CAE Baumam PFF Pinheiro R de Matteis RF Domeniconi 《Reproduction in domestic animals》2017,52(4):617-624
Aquaporins (AQPs) are channel proteins that facilitate the transepithelial and bidirectional movement of water. AQP9 is an aquaporin that is expressed in the mammalian epididymis. This water transport contributes to epididymal sperm concentration. This study aimed to examine the morphology of epididymal epithelium in piglets and boars, as well as the expression and immunolocalization of AQP9. The piglets presented an epididymal epithelium in differentiation with principal, basal and apical cells. The cellular population of the epididymal epithelium in boars consisted of principal, basal, apical, clear and narrow cells. The migratory cells known as halo cells were observed in the epididymis of both piglets and boars. AQP9 expression presented differences between piglets and boars. Moderate intensity of AQP9 immunoreaction was observed in the apical border of the epididymal epithelium of the caput and cauda regions in the piglet epididymis. A moderate‐to‐intense reaction for AQP9 was observed in the nuclei of epithelial cells of the three epididymal regions in the boar epididymis. The region of the cauda epididymis showed reactivity for AQP9 also in the apical border of the epithelium. It is believed that the AQP9 is already functional in piglets at only 1 week of age and is more active, playing a pivotal role in the caput and cauda regions of the epididymis. Moreover, the intense AQP9 expression in the apical border of epithelial cells in the cauda region of the boar epididymis suggests a higher performance of AQP9 in this region, where sperm complete their maturation process, stored and concentrated. 相似文献
88.
An attempt was made to determine plasma concentrations of, 13, 14‐dihydro‐15‐keto‐prostaglandin F2α (PGFM), cortisol and progesterone during periparturient period in yak. Plasma PGFM level showed an increasing trend beginning day 5 prior to parturition (0.48 ± 0.14 ng/ml) and increased steeply thereafter to reach a peak level (17.16 ± 1.31 ng/ml) on the day of parturition. The levels, then, declined sharply on day 1 postpartum to reach 1.20 ± 0.40 ng/ml and thereafter declined gradually over the days to reach 0.28 ± 0.09 ng/ml on day 20 postpartum and this level was maintained with fluctuation within narrow limits thereafter till conclusion of the blood sampling on day 90 post‐calving. The plasma progesterone concentration on days 7 and 6 before parturition was high (2.10 ± 0.10 and 2.12 ± 0.10 ng/ml, respectively). The level then decreased gradually and abrupt fall was observed 1–2 days before parturition and became basal on day of parturition (0.24 ± 0.04 ng/ml). This basal level was maintained till the end of the blood sampling on day 90 postpartum. Plasma cortisol level showed an increasing trend beginning day 2 prior to parturition (2.36 ± 0.65 ng/ml) and increased steeply thereafter to reach a peak level (26.65 ± 5.28 ng/ml) on the day of parturition. The levels, then, declined gradually over the days and touched 2.36 ± 0.25 ng/ml on day 3 postpartum and this level was maintained with fluctuation within narrow limits thereafter till day 7 post‐calving. 相似文献
89.
Bastian SF 《Journal of the American Veterinary Medical Association》2004,225(1):31-2; author reply 32
90.
Kwon OD Yim CY Jeong KS Park SC Jung KY McGregor JR Bastian NR Samlowski WE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(5):357-365
Nitric oxide (NO*) synthesis is induced within many tumors. The time course of NO* synthesis was evaluated during intra-peritoneal Meth A fibrosarcoma progression. While increasing macrophage recruitment into ascites was noted, inducible nitric oxide synthase (iNOS) antigen and function peaked between days 3-6 after tumor implantation. The capacity of cells to respond to LPS and IFNgamma stimulation was markedly depressed on day 9 and 11. Cellular proliferation correlated in an inverse fashion with levels of NO* synthesis. Electron paramagnetic resonance spectroscopy and nitrotyrosine immunostaining failed to show accumulation of characteristic target cell lesions induced by NO*. These findings lead us to conclude that NO* production was increasingly suppressed during Meth A tumor progression. Depression of NO* production did not correlate with levels of the inhibitory cytokines TGFbeta and IL-10, but could be partially overcome by addition of sepiapterin (a tetrahydrobiopterin prodrug). Thus, depletion of essential co-factors necessary for iNOS function may contribute to depressed NO* responses during cancer progression. 相似文献