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191.
Five diets were formulated to provide an isoproteic daily dietary intake of 15 g kg?1 day?1, while maintaining daily starch intake ranging from 0 to 40 g kg?1 day?1. The 4‐week experiments started with initial mean weights of 4.7 and 4.4 g for Pangasius bocourti and P. hypophthalmus, respectively. The results clearly show the protein sparing action of starch in both species. Best protein retention was obtained with starch intake of 20 and 10 g kg?1 day?1 for P. bocourti and P. hypophthalmus, respectively, which was equivalent to 40 and 20% starch in the feed. Pangasius bocourti and P. hypophthalmus fingerlings attained maximal growth with starch intake of 30 and 10 g kg?1 day?1, equivalent to 60 and 20% starch in the feed. It was noted that body lipid accumulation was much higher in P. bocourti than in P. hypophthalmus, and that excess dietary starch intake depressed diet digestibility and growth. 相似文献
192.
Background
Dense genetic maps, together with the efficiency and accuracy of their construction, are integral to genetic studies and marker assisted selection for plant breeding. High-throughput multiplex markers that are robust and reproducible can contribute to both efficiency and accuracy. Multiplex markers are often dominant and so have low information content, this coupled with the pressure to find alternatives to radio-labelling, has led us to adapt the SSAP (sequence specific amplified polymorphism) marker method from a 33P labelling procedure to fluorescently tagged markers analysed from an automated ABI 3730 xl platform. This method is illustrated for multiplexed SSAP markers based on retrotransposon insertions of pea and is applicable for the rapid and efficient generation of markers from genomes where repetitive element sequence information is available for primer design. We cross-reference SSAP markers previously generated using the 33P manual PAGE system to fluorescent peaks, and use these high-throughput fluorescent SSAP markers for further genetic studies in Pisum. 相似文献193.
Emmanuelle Roque d'Orbcastel Jean-Paul Blancheton Thierry Boujard Yves Moutounet Alain Belaud 《Aquaculture (Amsterdam, Netherlands)》2008,274(1):72-79
European water legislation enforces increasingly restrictive measures with regards to reduction of water consumption and waste emission in order to minimise the potential environmental impact of the agro industry sector. Fish farms are particularly concerned, but legislation covering effluent discharge varies significantly from country to country. However, recommendations and directives from institutional, national or regional bodies suggest the enforcement of increasingly strict waste reduction measures and the development of waste treatment. Before treatment, it is necessary to evaluate waste production in terms of composition and quantity. The waste quantification methods used today for fish culture systems are either based on direct measurements of nutrient and suspended solid fluxes or on indirect evaluation based on the digestibility coefficients of the feed constituents. The objective of the present study is to evaluate the waste of a freshwater flow through farm using both approaches and to discuss their applicability, drawbacks and advantages from the viewpoints of fish farmers and control authorities. Waste production on the farm was monitored during several 24 hour cycles in order to characterise the effluents of the system. The predictions and measurements for the total nitrogen (TN) parameter were well correlated, but measured and predicted suspended solids (SS) and total phosphorus (TP) values presented a weaker correlation coefficient. The hydrobiological method gives details on the N and P forms of waste but this method is heavy and it is difficult to obtain representative samples and flow rate measurements. The nutritional method is the simplest to use, provided that feed data are available. 相似文献
194.
L. M. Ware E. Marx M. A. Lindsay C. H. Metzger Eugene W. Whitman W. B. Ward Henry R. Talmage A. C. Moreau H. A. Reiley Marx Koehnhe J. C. Campbell E. V. Hardenburg M. E. Gardner E. B. Tussing C. A. Henderson K. W. Lauer O. D. Burke C. N. Clayton H. L. Bailey G. S. Ralston E. W. Harbor 《American Journal of Potato Research》1943,20(6):169-169
195.
196.
L. M. Ware E. Marx M. A. Lindsay C. H. Metzger Eugene W. Whitman W. B. Ward Henry R. Talmage A. C. Moreau H. A. Reiley Marx Koehnhe J. C. Campbell E. V. Hardenburg M. E. Gardner E. B. Tussing C. A. Henderson K. W. Lauer O. D. Burke C. N. Clayton H. L. Bailey G. S. Ralston E. W. Harbor 《American Journal of Potato Research》1943,20(5):126-140
197.
Riou E Havea P McCarthy O Watkinson P Singh H 《Journal of agricultural and food chemistry》2011,59(24):13156-13164
The effect of added CaCl(2) on heat-induced changes in whey protein (WP) solutions prepared from whey protein isolate (WP1), acid whey protein concentrate (WP2), and cheese whey protein concentrate (WP3) was investigated. The loss of native-like, proteins, aggregation, and gel firmness of WP were maximum at certain levels of added CaCl(2). These levels were different for different WP products. The effect of added CaCl(2) on these changes appeared to be related to the initial calcium concentrations of these solutions. The higher the calcium content of the product, the less available sites for added CaCl(2) to bind. It was considered that addition of CaCl(2) changed the types of protein interactions that formed the protein aggregates during heating. Added calcium caused dramatic decreases in fracture stress of WP gels due to the formation of large protein aggregates. 相似文献
198.
ABSTRACT: Babesia divergens is a tick-transmitted apicomplexan parasite for which asexual multiplication in its vertebrate hosts is restricted to erythrocytes. Current knowledge of invasion of these target cells is limited. An efficient in vitro invasion assay was set up to gain access to this information. Parasites prepared from infected RBC, lysed by electroporation, and mixed with bovine RBC in a selected synthetic medium (RPMI 1640 supplemented with calcium) were able to establish subsequent cultures with parasitemia ranging from 6 to 14%. Free parasites remaining in the invasion medium could be eliminated by Percoll gradient and culture could be pursued with the freshly invaded erythrocytes. In this way, the invasion time window could be shortened to obtain a synchronised start of the culture or to study the kinetics of invasion. With this assay we demonstrate that 1) erythrocyte invasion by B. divergens is a rapid process since 70% of the invasion-competent parasites invaded the RBC in less than 45 s; 2) all invasion-competent parasites achieved invasion within 10 min of contact; 3) one erythrocyte could be invaded concomitantly by two merozoites; 4) despite a synchronous start, the parasite population evolved heterogeneously resulting in a progressive loss of synchronisation. Western blot analysis of proteins collected from invasion medium were performed with sera from animals experimentally infected with B. divergens and highlighted several proteins. The dose-dependent, inhibitory effects of these sera on B. divergens invasion suggest that these proteins might be involved in the invasion process. Further investigations are required for their characterisation. 相似文献
199.
Roy J Bédard C Moreau M 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(3):277-282
A blinded randomized study was conducted on 24 cats to confirm the presence of bacterial and/or fungal secondary infections associated with otoacariasis and to verify the efficacy of Oridermyl, an acaricidal/antibiotic/antifungal/anti-inflammatory ointment, for treatment of the primary infestation and secondary infections. Sixteen cats were treated once daily for 10 d; 4 cats were not treated and 4 were treated with a placebo ointment. On Days 0 and 10, ears were swabbed for counts of bacteria and yeasts, for bacterial culture and sensitivity, and examined for determination of the degree of clinical otitis. Auricular secretions were removed for mite counts on Day 10, except for 8 treated cats that were done on Day 30. There was a high number of bacteria and yeasts in most cats and Oridermyl treatment significantly decreased those numbers. Staphylococci were the most frequently isolated bacteria. No live ear mites were found in cats treated with Oridermyl or the placebo ointment. 相似文献
200.
A process was developed to produce a germ‐enriched fraction from hull‐less barley using a Fitzpatrick comminuting mill (FitzMilling) followed by sieving. Hulled and hull‐less barleys contain 1.5–2.5% oil and, like wheat kernels, which contain wheat germ oil, much of the oil in barley kernels is in the germ fraction. A process that combined FitzMilling and sieving produced a germ‐enriched fraction with an oil content of ≈15% and a yield of ≈1.1%. For comparison, this is higher than the levels of oil in most samples of commercial wheat germ. Experimental conditions were also described to produce a germ‐enriched fraction with a higher yield (2.16%), but it would have lower oil content (10.24%). Germination and compositional analysis studies suggested that FitzMilling hull‐less barley for 2 min or longer reduced germination rates to 1% or less, which was interpreted to mean that almost the entire viable germ was removed. In contrast, FitzMilling conventional hulled barley for 4 min had no effect on germination, and milling for 6 and 8 min resulted in germination rates of 36 and 12%, respectively. The oil extracted from germ‐enriched fractions was rich in free phytosterols (≈1%), phytosterol esters (3–7%), and free fatty acids (2–10%). These germ‐enriched fractions and the extracted oil they contain may have value as nutraceuticals or premium edible oils. 相似文献