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71.
Chicken embryo has long been an important experimental model in basic and applied science because of its clear development process,especially in the early development of chicken embryo chorioallantoic membrane stage,due to its abundant blood vessels,it is a natural immunodeficiency host and can be used as an ideal experimental model for pathology,pharmacology and oncology research.The authors briefly described the tissue structure of early stage of chicken embryo,the application of chick embryo chorioallantoic membrane model in tumor,angiogenesis,organ transplantation,burn and other diseases,and the application of anti-cancer drug screening based on the pathological model of chicken embryo.The advances in the application of chicken embryo and avian cell lines in virus reproduction,vaccine production,therapeutic protein production and monoclonal antibody production were reviewed.A variety of human viruses,avian viruses and mycoplasma can proliferate in chicken embryos and avian cell lines and be used in vaccine production.In this paper,the development and characteristics of commonly used avian fibroblasts and pluripotent stem cells were described,and the source of commercial avian cell lines and some susceptible viruses were summarized.Chicken embryo expression system can produce human glycosylates at specific sites of target proteins,reduce the allergic reaction of the target protein to human,and poultry eggs are cheap and easily available,so it can be used as a suitable donor for the production of human monoclonal antibodies and therapeutic proteins.In this paper,the recent progress in the application of chicken embryos and avian cell lines in the field of biomedicine was introduced,and the future application of chicken embryos as animal models was forecasted. 相似文献
72.
Survey radiographs have not accurately identified renal contour or location in nonhuman primates. Excretory urography using 786 to 1193 mg iodinelkg body weight resulted in dense opacification of the renal parenchyma and pelvis. Abdominal compression improved visu- alization of the renal pelvis. Interpretation of the nonhuman primate excretory urogram was compromised by several anatomic characteristics of this animal group. Superimposition of the kidneys on the lateral radiograph limited evaluation of the renal contour. Since the renal pelvis in most species of nonhuman primates does not possess diverticula (as in the dog and cat) or a caliceal system (as in the pig and man), the diagnosis of pyelonephritis or renal mass lesions was difficult. Severe irregularities in the renal contour, size of the renal pelvis, or areas of deficient concentrating ability were identifiable in nonhuman primate excretory urograms, but the diagnosis of small cysts was not possible in smaller nonhuman primates. The presence of a caliceal collecting system in the spider monkey (Ateles sp.) suggests this animal as a potential model for the evaluation of human renal disease. 相似文献
73.
《Veterinary parasitology》2015,207(1-2):49-55
Natural anti-parasitic compounds in plants such as condensed tannins (CT) have anthelmintic properties against a range of gastrointestinal nematodes, but for other helminths such effects are unexplored. The aim of this study was to assess the effects of CT from three different plant extracts in a model system employing the rat tapeworm, Hymenolepis diminuta, in its intermediate host, Tenebrio molitor. An in vitro study examined infectivity of H. diminuta cysticercoids (excystation success) isolated from infected beetles exposed to different concentrations of CT extracts from pine bark (PB) (Pinus sps), hazelnut pericarp (HN) (Corylus avellana) or white clover flowers (WC) (Trifolium repens), in comparison with the anthelmintic drug praziquantel (positive control). In the in vitro study, praziquantel and CT from all three plant extracts had dose-dependent inhibitory effects on cysticercoid excystation. The HN extract was most effective at inhibiting excystation, followed by PB and WC. An in vivo study was carried out on infected beetles (measured as cysticercoid establishment) fed different doses of PB, HN and praziquantel. There was a highly significant inhibitory effect of HN on cysticercoid development (p = 0.0002). Overall, CT showed a promising anti-cestodal effect against the metacestode stage of H. diminuta. 相似文献
74.
Comparison of milk production of dairy cows kept in cold and warm loose-housing systems 总被引:2,自引:0,他引:2
A retrospective cohort study was conducted to test whether the lactation curves of cows kept in cold loose-housing systems (CLHs) were the same as for cows in warm loose-housing systems (WLHs) in the Nordic countries. Approximately 40 000 test-day records from 5366 Ayrshire or Black and White cows kept on 38 CLHs and 166 WLHs in Finland during 1996 and 1997 were used. Analysis used a random-coefficient model (correcting for parity, breed and calving-year-season and the correlation-structure between test-days of the same cow and cows of the same herd). Cows in a CLH produced up to 1 l less milk per test-day, but this difference was not statistically significant. Surprisingly, the difference in milk yield was not affected by calving-year-season, parity or breed. 相似文献
75.
76.
Hamid Mahyou Bernard Tychon Marie Lang Riad Balaghi 《African Journal of Range and Forage Science》2018,35(1):1-12
The assessment of rangeland productivity in semi-extensively grazed arid rangelands is a prerequisite for livestock management in relation to sustainable use of pastoral resources. The objective of this study was to assess rangeland productivity based on normalised difference vegetation index (NDVI) images. Data on phytomass were measured on 61 field samples in arid rangelands of Morocco, covering various rangeland categories during autumn (November) and spring (April), i.e. when phytomass is at low and high levels, respectively, for two consecutive years (2008 and 2009). Dekadal EROS Moderate Resolution Imaging Spectroradiometer (eMODIS) NDVI data were linearly regressed to field measurements for these four periods. Results show that phytomass values were correlated with NDVI during spring, with R2 and RMSE values of 0.82 and 0.3 t ha?1, respectively. This study indicates there is a high potential for operational use of remotely sensed data to estimate rangeland phytomass of semi-extensively grazed rangelands. 相似文献
77.
78.
Bussières G Jacques C Lainay O Beauchamp G Leblond A Cadoré JL Desmaizières LM Cuvelliez SG Troncy E 《Research in veterinary science》2008,85(2):294-306
This study addresses development and validation of a composite multifactorial pain scale (CPS) in an experimental equine model of acute orthopaedic pain. Eighteen horses were allocated to control (sedation with/without epidural analgesia - mixture of morphine, ropivacaine, detomidine and ketamine) and experimental groups: amphotericin-B injection in the tarsocrural joint induced pain and analgesia was either i.v. phenylbutazone administered post-induction of synovitis, or pre-emptive epidural mixture, or a pre-emptive combination of the 2. Inter- and intra-observer reproducibility was good (0.8相似文献
79.
R. Roehe N.P. Shrestha W. Mekkawy E.M. Baxter P.W. Knap K.M. Smurthwaite S. Jarvis A.B. Lawrence S.A. Edwards 《Livestock Science》2009,121(2-3):173-181
Genetic parameters of piglet survival traits and birth weight were estimated on the first generation data of a selection experiment aimed at improving piglet survival using a multiple trait linear and threshold model. Data on 5293 piglets for survival at birth, at day one after birth and during the entire nursing period, as well as individual birth weight and litter size, were recorded in an outdoor production system. Genetic effects of piglet survival traits and birth weight were estimated based on threshold and Gaussian models, respectively, using a Bayesian approach. The statistical model included as fixed effects selection group, parity, gender, fostering, gestation length and month of farrowing and, alternatively, an adjustment for litter size. Direct genetic effects (i.e. the piglet's genetic potential) for piglet survival and birth weight were estimated separately, whereas maternal genetic and environmental effects could only be estimated for the given data structure in a combined litter effect. Posterior means of heritabilities for direct genetic effects of survival at birth, at first day after birth and the entire nursing period, as well as birth weight, were 0.08, 0.07, 0.08 and 0.20, respectively. Genetic correlations among survival traits were in the range of 0.29 to 0.40 and indicate that these traits were mainly attributable to different genetic effects. Genetic correlations between direct effects of survival traits and birth weight ranged between 0.18 and 0.23 and were reduced when weights of stillborn piglets were omitted in the analysis or the traits were adjusted for litter size. The magnitudes of direct genetic effects of survival traits are substantially higher than estimates in the literature, which may indicate that these traits have a higher genetic influence under outdoor conditions. The use of birth weight in the multiple trait estimation provided important information for the estimation of survival traits due to its favourable genetic correlations with survival, its high heritability and its high information content as a continuously measured trait. 相似文献
80.
Santiago Peralta Angela L. McCleary‐Wheeler Gerald E. Duhamel Kristiina Heikinheimo Jennifer K. Grenier 《Veterinary and comparative oncology》2019,17(3):439-445
Ameloblastoma is a locally aggressive odontogenic tumour that occurs in humans and dogs. Most ameloblastomas (AM) in humans harbour mutually‐exclusive driving mutations in BRAF, HRAS, KRAS, NRAS or FGFR2 that activate MAPK signalling, and in SMO that activates Hedgehog signalling. The remarkable clinical and histological similarities between canine acanthomatous ameloblastoma (CAA) and AM suggest they may harbour similar driving mutations. In this study, aimed at characterizing the mutational status of SMO, BRAF, HRAS, KRAS, NRAS and FGFR2 in CAA, we used RNA sequencing, Sanger sequencing and restriction fragment length polymorphism assays to demonstrate that 94% of CAA (n = 16) harbour a somatic HRAS p.Q61R mutation. The similarities in MAPK‐activating mutational profiles between CAA and AM implicate conserved molecular mechanisms of tumorigenesis, thus, qualifying the dog as a potentially useful model of disease. Given the relevance of RAS mutations in the pathogenesis of odontogenic tumours and other types of cancer, the results of this study are of comparative, translational, and veterinary value. 相似文献