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891.
FC Varago VS Moutacas BC Carvalho RV Serapião F Vieira H Chiarini‐Garcia FZ Brandão LS Camargo M Henry MA Lagares 《Reproduction in domestic animals》2014,49(5):839-844
The aim of this work was to evaluate the efficiency of the cryoprotectants dimethylformamide and ethylene glycol for cryopreservation of ovine embryos using vitrification and conventional freezing. The recovered embryos were distributed randomly in three treatment groups: Gr. 1: conventional freezing (n = 44), Gr. 2: vitrification with ethylene glycol (n = 39) and Gr. 3: vitrification with dimethylformamide (n = 38). Quality of fresh embryos in control group as well as of frozen and vitrified embryos was examined by three methodologies: staining with propidium iodide and Hoechst 33258 and evaluation under fluorescent microscopy, evaluation of re‐expansion and hatching rates after culture, and determination of apoptotic index with TUNEL technique. It was established that re‐expansion rate in all treatment groups was similar. In the same time, hatching rates were higher in Gr. 1 (40.5%) and Gr. 2 (35.3%) in comparison with Gr. 3 (15.5%, p < 0.05). The number of dead cells in vitrified embryos of Gr. 2 and Gr. 3 was higher (42.6 ± 26.2 and 63.2 ± 34.65, respectively) in comparison with Gr. 1 (conventional freezing, 10.1 ± 8.5, p < 0.05). Embryos vitrified with dimethylformamide included the same quality of apoptotic cells that Gr. 1 (conventional freezing) and fresh embryos. In conclusion, the dimethylformamide and ethylene glycol used as cryoprotectant to vitrify ovine embryos, in the concentrations and exposition time tested in this work, were not as efficient as the conventional freezing for cryopreservation of ovine embryos Thus, the conventional freezing with ethylene glycol was the most efficient method to cryopreserve ovine embryos in comparison with vitrification. 相似文献
892.
Henry JФrgensen Trakarn Prapaspongsa Van Thi Khanh Vu Hanne Damgaard Poulsen 《畜牧与生物技术杂志(英文版)》2014,(2):199-207
Modern pig production contributes to many environmental problems that relate to manure, especially in areas with highly intensive production systems and in regions like Asia where the regulative control is not effective. Therefore, the objective of this study was to use three different pig diets varying in dietary protein, fibre and fat as representative for Danish (DK), Thai (TH) and Vietnamese (VN) pig production to develop and evaluate different approaches to predict/calculate excretion from growing pigs in comparison with the experimentally determined values. Nine female growing pigs were used in a digestibility and balance experiment. Excretion of dry matter (DM), nitrogen (N), phosphorus (P) and carbon (C) of the experimental diets were determined. Due to the highest dietary fibre content, VN had the lowest digestibility of N, P and C (73, 49, and 73%, respectively) compared with the DK and TH pig diets. From the known diet composition using standard table values on chemical and nutrient digestibly, high accuracy (bias) and low variation was found and the results could be used for prediction on chemical composition and excretion in faeces and urine in growing pigs. Calculation based on standard values regarding nutrient retention in the pig body as used in the Danish manure normative system (DMNS) showed likewise to be quite useful for quantifying the total excretion of N and P. Overall, the results demonstrate that simple models that require cheap and normally available information on dietary nutrients can give useful information on nutrient excretion in growing pigs. 相似文献
893.
Cheikh Mbow Michel M. Verstraete Bienvenu Sambou Amadou Tahirou Diaw Henry Neufeldt 《Journal of Forest Research》2014,19(3):340-347
This paper presents new allometric models for woody savanna of the dry Sudanian zone of the southern part of Senegal and contributes to the needs for accurate and precise carbon estimates through improved statistical models and methods. The results are based on statistical relationships between the total dry biomass and either tree diameter at breast height (DBH) or tree height for a set of 101 individuals of different sizes from 13 dominant species in 6 protected forests. The statistical regression (cubic order 3) generated for DBH (5–41.5 cm) and tree height (2.5–15.6 m) showed significant R 2 of 0.934 and 0.813, respectively. Using the same database, species-based models for the most represented genera (Acacia sp., Combretum sp. and Terminalia sp.) show more precision than the generic model. The model residual standard error and relative errors showed a good fit between observed and predicted data. Species-based models showed smaller errors compare to generic models outputs. 相似文献
894.
The carbohydrate content of Hordeum spotaneum lines collected from 23 diverse environments in Israel was investigated. The range in composition was sucrose: 0.83—1.15%; trisaccharides): 0.48—1.16% total free and combined fructose: 1.2—4.2%; pentosans: 4.2—9.9%; and fl→3), (1→4)-β-glucans: 4.5—13.2%. The high pentosan and β-glucan content in some lines would cause quality problems if found in malting barleys. 相似文献
895.
H. L. Ko D. C. Cowan R. J. Henry G. C. Graham A. B. Blakeney L. G. Lewin 《Euphytica》1994,80(3):179-189
Summary The genetic relationships between rice varieties were analysed by using the polymerase chain reaction (PCR), with arbitrary oligonucleotide primers in the random amplified polymorphic DNA (RAPD) method. PCR with 22 arbitrary primers applied to 37 varieties produced 144 useful markers, of which 67% were polymorphic. Thus, with selected primers sufficient polymorphism could be detected to allow identification of individual varieties. Visual examination of electrophoresis gels and analysis of banding patterns confirmed that commercial Australian and USA lines and their relatives were very closely related, with similarity indices of 88–97%. Three varieties originating from more distant geographical centres were easily distinguished, producing variety-specific amplification profiles and expressing a lower similarity index of 80% to all other varieties tested. PCR offers a potentially simple, rapid and reliable method for rice genotype identification and recognition of lines that could contribute genetic diversity to new commercial varieties.Abbreviations PCR
Polymerase Chain Reaction
- RAPD
Random Amplified Polymorphic DNA 相似文献
896.
A collection comprising 157 Aegilops geniculata accessionsoriginating from different ecogeographical regions was established atENSA-INRA, Montpellier. The accessions were studied for physiologicaltraits related to drought and heat stress and screened for resistance tobarley yellow dwarf virus (BYDV) and rusts. Some accessions were alsotested for resistance to Hessian fly and cereal cyst nematodes (CCN). The study allowed to distinguish different adaptive strategies to theclimatic constraints encountered by Aegilops populations in theirregion of origin. They led to significant differences in biomass and grainproduction and should be taken into account in the utilisation of Ae.geniculata germplasm in wheat breeding programs. Two accessions withresistance to BYDV were found. Both originated from South of France. Theinterest of Ae. geniculata as a source of rust resistance was confirmedand accessions with resistance to the three rusts were identified. Highresistance against populations of Heterodera avenae and H.latipons was found in accessions from Spain, Bulgaria, Jordan and Tunisia.Sources of resistance to Hessian fly were also identified. 相似文献
897.
J. De Buyser S. Hachemi-Rachedi M.-L. Lemee S. Sejourne J.-L. Marcotte Y. Henry 《Plant Breeding》1992,109(4):339-342
Genetic stocks of Triticum aestivum including the disomic, 8 ditelosomic and 3 nullisomic-tetrasomic ‘Chinese Spring’ wheat lines were employed to ascertain the chromosomal arm locations of the genes acting on the production of embryos from micro-spores and on the regeneration capacity (green and albina) of the microspore-derived embryos. All these aneuploid lines differed significantly from the parental line ‘Chinese Spring’ for embryo production. Our results confirmed or in most cases established that genes affecting embryo production are located on several chromosomal arms: IBS, 1BL, 3AS, 3AL, 5AS, SAL, 5BS, 5BL, 7DS, 7DL. Whereas most of the chromosomal arms stimulate the production of embryos from the microspores, IBS and 1BL reduce it. The results of plant production from microspore-derived embryos suggest that the genes increasing regeneration ability are located on CS5A chromosome and are likely associated to a gene increasing green plant frequency. On the contrary, the 1BL arm increases the albina frequency. 相似文献
898.
R. J. Henry 《Euphytica》1985,34(1):135-145
Summary Methods for assessing malting quality in barley breeding were evaluated for their precision, including variation between different batches, analysts and barley samples. The barley characters measured were grain moisture, ground grain moisture (two methods), grain weight, steep moisture, malt moisture (two methods), malt yield, malt nitrogen, malt soluble nitrogen, Kolbach index, malt diastatic power, malt -amylase, malt -glucanase, wort refractive index, hot water extract, extract yield, wort reducing sugars, wort total carbohydrates, wort -amino nitrogen and wort total nitrogen. The value of these measurements in barley breeding is discussed. 相似文献
899.
Henry Jørgensen Kirsten Jakobsen Bjørn O. Eggum 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(3):177-184
Abstract The influence of dietary protein, fat and mineral levels on crude fat and fatty acid digestibility was investigated in growing pigs. The experiment was a factorial design with two levels of protein (normal and high), two levels of dietary fat (3 and 15% of DM) and three levels of minerals (50, 100 and 150% of Danish Standard). Four litters, each of six female pigs, were used in the experiment. Increasing the dietary protein content resulted in a moderate but significant increase in the ileal digestibility of fatty acids. The increase was most pronounced for the saturated fatty acids. Addition of animal fat to the basal diet caused a substantial increase in ileal digestibility of all fatty acids except stearic acid (18:0). A variation in the dietary mineral content of ±50% of the Danish Standard had no significant influence on ileal digestibility of crude fat and fatty acids. Apparently, microbial hydrogenation occurred in the hind-gut, but the increase in stearic acid (18:0) excretion could not be explained solely by biohydrogenation of unsaturated fatty acids. The interactions between dietary protein and fat on the increase of faecal 18:0 showed that the dietary composition had a very complex effect on the microbial activity in the hind-gut. Consequently, determination of fatty acid digestibility should be performed at the terminal ileum, whereas crude fat (Stoldt) digestibility can be carried out on faecal material. 相似文献
900.