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101.
本试验的目的是为了研究日粮中维生素A的含量对猪肉中脂肪酸组成的影响。采用128只杜洛克×(大白×长白)阉割公猪,随机分组,每个圈里4只猪。对照组16个圈中猪日粮的维生素A为基础水平(7500IU/kg),处理组16个圈中猪日粮的维生素A含量丰富(100,000IU/kg)。在平均体重达125.9kg时进行屠宰。结果未发现维生素A水平对生长性能、胴体性状及肌内脂肪的影响。 相似文献
102.
Serotypes,phage types and virulence genes of shiga-producing Escherichia coli isolated from sheep in Spain 总被引:3,自引:0,他引:3
Rey J Blanco JE Blanco M Mora A Dahbi G Alonso JM Hermoso M Hermoso J Alonso MP Usera MA González EA Bernárdez MI Blanco J 《Veterinary microbiology》2003,94(1):47-56
PROBLEM ADDRESSED: Shiga toxin-producing Escherichia coli (STEC), have emerged as food poisoning pathogens which can cause severe diseases in humans. OBJECTIVE: The aim of this study was to determinate the serotypes and virulence genes of STEC strains isolated from sheep in Spain, with the purpose of determining whether sheep represent a potential source of STEC pathogenic for humans. METHODS AND APPROACH: Faecal swabs obtained from 697 healthy lambs on 35 flocks in Spain during the years 2000 and 2001 were examined for STEC using phenotypic (Vero cells) and genotypic (PCR) methods. RESULTS: STEC O157:H7 strains were isolated from seven (1%) animals in six flocks, whereas non-O157 STEC strains were isolated from 246 (35%) lambs in 33 flocks. A total of 253 ovine STEC strains were identified in this study. PCR showed that 110 (43%) strains carried stx(1) genes, 10 (4%) possessed stx(2) genes and 133 (53%) both stx(1) and stx(2). Enterohaemolysin (ehxA) and intimin (eae) virulence genes were detected in 120 (47%) and in 9 (4%) of the STEC strains. STEC strains belonged to 22 O serogroups and 44 O:H serotypes. However, 70% were of one of these six serogroups (O6, O91, O117, O128, O146, O166) and 71% belonged to only nine serotypes (O6:H10, O76:H19, O91:H-, O117:H-, O128:H-, O128:H2, O146:H21, O157:H7, O166:H28). A total of 10 new O:H serotypes not previously reported in STEC strains were found in this study. Seven strains of serotype O157:H7 possessed intimin type gamma1, and two strains of serotype O156:H- had the new intimin zeta. STEC O157:H7 strains were phage types 54 (four strains), 34 (two strains) and 14 (one strain). CONCLUSIONS: This study confirms that healthy sheep are a major reservoir of STEC pathogenic for humans. However, because the eae gene is present only in a very small proportion of ovine non-O157 STEC, most ovine strains may be less pathogenic. 相似文献
103.
L. M. Rey Susanne K. Whitaker Gretchen Stephens 《Journal Of Agricultural & Food Information》2013,14(3):253-270
This article discusses the Veterinary Medical Libraries Section (VMLS) of the Medical Library Association (MLA), its impacts on both librarianship and veterinary medicine during its 40-year history, how it achieved those impacts, relationships, selected projects, and organizational changes through the years. A listing of publications about veterinary librarianship and VMLS products is available on the VMLS website (Veterinary Medical Libraries Section, 2014). 相似文献
104.
‘Samantha’ roses (Rosa hybrida L.) potted in sand or soil mixture were grown under natural or HPS supplementary irradiation and fertilized with 0.05, 0.25, 0.5, 2.5 or 5.0 ppm Cu in each irrigation. Foliar and root Cu contents increased relative to the Cu level in solution while leaf and root Fe contents were reduce with higher concentration of Cu applied. Growing medium influenced the pattern of foliar content response to Cu concentration. In sand, the effect of Cu level in solution was evident from the beginning of the experiment whereas in soil mixture the effect was observed only after six months. Plant growth and flower production was reduced only in plants grown in sand and fertilized with 2.5 and 5.0 ppm Cu. No Cu deficiency symptoms were observed even though leaf content in plants grown in soil mixture was as low as 2.2 ppm. High Cu level in solution induced Fe deficiency symptoms, especially in plants grown in sand. Supplementary irradiation did not influence the effect of Cu fertilization level on foliar content or flower production. Most of the Cu applied was retained in the upper 5 cm layer of soil mixture reducing its availability for plant uptake. 相似文献
105.
J. García-Alonso A. Nappa G.M. Somoza A. Rey D. Vizziano 《Fish physiology and biochemistry》2003,28(1-4):337-338
The main steroids produced by three stages ovarian fragments (post-vitellogenic PV, oocytes in GV migration phase Mtg and mature oocytes M) of white croaker were compared. In Mtg and M stages 17,20β-dihydroxy-4-pregnen-3-one (17,20βP), 17,21-dihydroxy-4-pregnene-3,20-dione (17,21P) and 17,20β,21-trihydroxy-4-pregnen-3-one (20β-S) were synthesised. The specific synthesis of 20βS in Mtg oocytes suggests a MIS role for this steroid. 相似文献
106.
Yada Chutimanitsakun Alfonso Cuesta‐Marcos Shiaoman Chao Ann Corey Tanya Filichkin Scott Fisk Mathias Kolding Brigid Meints Yee‐Ling Ong Juan Ignacio Rey Andrew S. Ross Patrick M. Hayes 《Plant Breeding》2013,132(6):563-570
Barley (Hordeum vulgare) is an important component of heart‐healthy whole grain diets because it contains β‐glucan. All current US barley varieties with high β‐glucan are spring habit and have waxy starch. Winter varieties have agronomic advantages but require low‐temperature tolerance (LTT). Vernalization sensitivity (VS) is associated with higher levels of LTT. To rapidly develop fall‐sown varieties with LTT and higher grain β‐glucan, we therefore used marker‐assisted selection (MAS) at the WX and VRN‐H2 loci. The MAS‐derived lines, together with unrelated non‐waxy germplasm developed via phenotypic selection (PS), were used for a genome‐wide association scan (GWAS). The panel was phenotyped for grain β‐glucan, LTT and VS. It was genotyped with 3072 single‐nucleotide polymorphisms (SNPs) and allele‐specific primers. Marker‐assisted selection fixed target alleles at both loci but only one of the target phenotypes (higher β‐glucan percentage) was achieved. Variation for VS and LTT is attributable to (i) incomplete information about VRN‐H1 at the outset of the project and (ii) unexpected allelic variation at VRN‐H3 with a large effect on VS and LTT. 相似文献
107.
The relationship between groundwater and landscape in representative areas of the Spanish plateaux is discussed, with special attention given to the Douro River basin. The study focusses on the transference of water and matter that is conditioned by groundwater flow systems, and also on water bodies, wet meadows, marshes, saline soils under their influence.These factors are of great importance in semiarid areas. Using photointerpretation, interviews, vegetation plots, water samples from wells and springs and soil samples, and the results of data processing (principal component analysis, shared information) we find that hydrological processes are the main controlling factor in the ecological function and variation of uncultivated lowlands. These processes include the alternation of recharge and discharge areas, the geochemical evolution of groundwater and the independent flows of the regional system.The landscapes in recharge and discharge areas are compared, as well as the influence of the evolutionary stage of the groundwater in the latter areas (glycophyte or halophyte vegetation). After observing the ecological importance of these aquifer discharges systems, the causes of their accelerated transformation are analyzed. 相似文献
108.
109.
F. Rey J. M. Hallebeek & A. C. Beynen 《Journal of animal physiology and animal nutrition》2001,85(7-8):251-254
The question addressed was whether apparent crude fibre digestibility in ponies would change after lowering protein intake from adequate to borderline deficient. Four adult ponies were fed a low- and high-protein diet according to a cross-over design. The diets consisted of grass hay and concentrates and provided either 1.5 or 3.6 g digestible crude protein/kg0.75 per day. The two whole rations provided 2.4 g crude fibre/kg body weight per day. Apparent crude fibre digestibility was not affected by protein intake (low-protein diet: 42.9 ± 4.03%; high-protein diet: 38.1 ± 1.14%, means ± SE, n =4). The low-protein diet caused a significant increase in the ratio of faecal: urinary nitrogen. It is suggested that, when the low-protein diet was fed, sufficient urea flew from the blood into the intestine and ammonia released in the hindgut was conserved so that microbial growth, and thus fibre fermentation, was maintained. 相似文献
110.
Encouraged by the success of the global smallpox eradication certified in 1980, the global poliomyelitis eradication program was launched in 1988 by the World Health Organization (WHO). In addition to routine polio immunization included in the Expanded Program of Immunization (EPI), two major activities were planned: mass polio vaccination campaigns and surveillance of all cases of acute flaccid paralysis. In 2000, the disease had been eliminated from most countries in the world. However, as of 2002, the community acceptance of vaccination was endangered in some countries by rumors about assumed adverse effects of oral polio vaccine. The rejection of polio immunization provided a worrying resurgence of polio in Northern Nigeria, followed by re-infection of 21 countries, whereas resurgence of the disease also was observed in Northern India. Supplementary vaccination activities were resumed, additional resources were mobilized and, in 2007, most re-infected countries became polio-free again. Today, polio remains endemic in only four countries. The goal of global polio eradication has now been set at 2010, but doubts have been expressed about the feasibility of its achievement. 相似文献