额河银鲫食性的初步研究

对额河银鲫的食性和年龄与生长关系进行了调查研究。结果表明：额河银鲫是一种杂食性鱼,它的主要食物组成是藻类、水生植物、原生动物、水生混虫、轮虫以及小鱼等。在食物成分上有性变化。在春季和夏季主要摄性食物而秋季主要摄食动物性食物。     

Carcass yields,muscle amino acid and fatty acid profiles,and antioxidant indices of broilers supplemented with synbiotic and/or organic acids

The objective of the current research was to explore the possible impacts of dietary supplementation with synbiotic and/or organic acids (OA) on the performance traits, carcass yields and muscle amino acid and fatty acid (FA) profiles of broilers. Randomly, a total of 160 day‐old chicks (Ross 308) were assigned into four equal groups (40 birds each), with each group subdivided into eight replicates (five birds/pen). The control group (CON) fed the basal diet with no supplements, while diets of the treated groups were supplemented with OA (Sodium butyrate 40%; 1 g/kg), synbiotic (comprised Bacillus subtilis, Saccharomyces cerivisiae, Streptococcus faecium, Mannan‐Oligosaccharides and β‐Glucan; 1 g/kg) and equal mix of OA and synbiotic (2 g/kg). Broilers fed the diets supplemented with synbiotic or synbiotic plus OA produced a significantly higher feed utilization efficiency (p = 0.021) and carcass yields (p = 0.038) than the CON and OA‐supplemented groups. The group fed the diet supplemented with the synbiotic showed lowered serum cholesterol (p = 0.049), triglycerides (p = 0.001) and very low density lipoprotein (p = 0.032) when compared with the CON group. Regarding the polyunsaturated FA (PUFA) of breast muscles, synbiotic‐supplemented birds had significantly lower n‐6:n‐3 ratio (p = 0.047), however, a greater hypocholesterolaemic to hypercholesterolaemic FA (H/H) ratio was reported when compared with the CON group (p = 0.002). Among the essential amino acids, the contents of leucine and methionine in the breast (p = 0.032 and 0.007 respectively) and thigh (p = 0.023 and 0.003 respectively) muscles were greater in the synbiotic‐supplemented birds compared with the CON group. In conclusion, the synbiotic‐supplemented diet improved the PUFA:SFA, n‐6:n‐3 and H/H ratios by altering the FA composition of broiler muscles, which are important with regards to human health.     

Alleviation of soil acidity improves the performance of oil palm progenies planted on an acid Ultisol

Abstract

Soil acidity is one of the main factors that limit profitable and sustained agricultural production. Oil palm (Elaeis guineensis Jacq.) is mainly planted in acidic soils. In the last years, there has been a stagnated yield and increases in disease incidence and severity worldwide that could be attributed in some extent to soil acidity. This study was conducted to determine the effects of soil acidity alleviation on oil palm seedlings. The effects of ground magnesium limestone or dolomite and magnesium carbonate (0, 1.1, 2.2, 3.3 and 4.4 t ha^?1) applied to an Ultisol dominated by kaolinite (pH in water 4.4) were evaluated on selected morphological, physiological and nutritional characteristics of hybrid (Deli dura × AVROS pisifera) and clonal (clone 366) oil palm progenies under nursery conditions for 8 months. Increasing rates of ground magnesium limestone and magnesium carbonate showed a significant effect on improving soil pH and lowering exchangeable aluminium. The hybrid oil palm showed significant either linear or quadratic trends for most of the parameters evaluated, indicating that the best responses for morphological and physiological traits were achieved from 2.5 to 4.23 t ha^?1 with ground magnesium limestone and 2.87 to 3.45 t ha^?1 with magnesium carbonate. Positive effects of increasing rates of ground magnesium limestone and magnesium carbonate were observed on nitrogen and magnesium uptake. Aluminium concentration in the third frond decreased significantly with increasing ground magnesium limestone rate. A significant reduction of manganese uptake was also observed with increasing rates of both ameliorants. The clonal oil palm progeny exhibited a better performance on un-amended treatment. This may be explained by the significant higher root growth of this progeny. Soil acidity alleviation improved the oil palm seedling growth. These results are important for the oil palm industry and could be applied in the nursery stage as well as extended to the immature stage.     

Folate deficiency is associated with nutritional anaemia in Lebanese women of childbearing age

OBJECTIVE: The objective of this study was to identify the determinants of anaemia in Lebanese women of childbearing age attending health centres in Lebanon. DESIGN: Cross-sectional study carried out between May and December 2003. Anthropometric measurements as well as sociodemographic, health and dietary intake data were collected using a questionnaire. Haemoglobin (Hb), plasma ferritin, plasma folate and vitamin B12 were assessed using standard laboratory methods. SETTING: Governmental health centres in Lebanon. SUBJECTS: Four hundred and seventy non-pregnant Lebanese women aged 15-45 years. RESULTS: Anaemia (Hb <12 g dl(-1)) and iron deficiency (ferritin <15 microg l(-1)) were prevalent in 16.0 and 27.2% of the study sample, respectively. Of the total sample, 7.7% had iron-deficiency anaemia. The percentage of women with either Hb or ferritin deficiency or both was 35.6%. Plasma folate and vitamin B12 deficiency was reported in 25.1 and 39.4%, respectively, and 12.6% of the women had both folate and vitamin B12 deficiencies. Of the anaemic group, 48.0% of the women had iron deficiency. The intake of iron was lower in iron-deficient than in non-deficient women and a positive relationship was shown between folate intake and its corresponding serum levels. Regression analysis showed that ferritin, plasma folate and family history of anaemia were significant determinants of the anaemia in the sample of women. CONCLUSIONS: Anaemia not related to iron deficiency was partly explained by plasma folate deficiency. Measures to control folate and iron deficiency should be considered.     

Characterization of protection from systemic infection and disease by use of a modified-live noncytopathic bovine viral diarrhea virus type 1 vaccine in experimentally infected calves

OBJECTIVE: To evaluate protection against systemic infection and clinical disease provided by use of a modified-live noncytopathic bovine viral diarrhea virus (BVDV) type 1 vaccine in calves challenged with NY-1 BVDV. ANIMALS: 10 calves, 5 to 7 months of age. PROCEDURES: Calves were allocated (n = 5/group) to be nonvaccinated or vaccinated SC on day 0 with BVDV type 1 (WRL strain). Calves in both groups were challenged intranasally with NY-1 BVDV on day 21. Calves' rectal temperatures and clinical signs of disease were recorded daily, total and differential WBC and platelet counts were performed, and serum neutralizing antibody titers against NY-1 BVDV were determined. Histologic examinations and immunohistochemical analyses to detect gross lesions and distribution of viral antigens, respectively, were performed. RESULTS: After challenge exposure to NY-1 BVDV, nonvaccinated calves developed high rectal temperatures, increased respiratory rates, viremia, leukopenia, lymphopenia, and infection of the thymus. Vaccinated calves did not develop high rectal temperatures or clinical signs of respiratory tract disease. Vaccinated calves appeared to be protected against systemic replication of virus in that they did not develop leukopenia, lymphopenia, viremia, or infection of target organs, and infectious virus was not detected in peripheral blood mononuclear cells or the thymus. CONCLUSIONS AND CLINICAL RELEVANCE: The modified-live BVDV vaccine protected calves against systemic infection and disease after experimental challenge exposure with NY-1 BVDV. The vaccine protected calves against infection and viremia and prevented infection of target lymphoid cells.     

The Clinical and Morphological Characteristics of the Uterus of the Goat during the Period of Involution

Two goats were slaughtered at zero, 24, 62 hours and five, seven, nine, 12, 15, 18, 21, 25, 28, 32 and 36 days after kidding in order to study the involutionary changes of the uterus.     

In vitro development of mouse pronuclear embryos to blastocysts in sequential media with and without co-culture of autologous cumulus cells

The objective of this study was to use mouse embryos as a model system to investigate the effect of co-culture of cumulus cells in Sydney IVF sequential media (Cook) on embryo development, based on the hypothesis that feeder cells in co-culture with a sequential medium could work synergistically to further improve in vitro culture conditions for mammalian preimplantation embryos. The culture systems described here were evaluated by the ability to consistently produce high blastocyst formation rates and high cell number per blastocyst. The role of embryo-to-cell contact was assessed by using Transwell inserts with transparent microporous membranes. Pronuclear embryos of ICR mice were cultured to blastocysts in Cook sequential media, with and without mouse primary cultures of cumulus cells, and with or without inserts. Blastocyst formation rates and cell numbers of in vitro developing embryos in the different culture systems were compared to each other, and to in vivo derived blastocysts. Blastocyst formation rates for Cook medium only was 27.8% (without inserts) and 32.9% (with inserts), whereas Cook-Cumulus cells in identical culture systems was significantly higher at 45.8% (without inserts, P<0.05) and 55.6% (with inserts, P<0.05). When the embryos are suspended above the bottom of the well, for Cook medium significantly lower blastocyst formation rates were observed at 4.2% compared to Cook-Cumulus cells at 17.5% (P<0.05). Mean cell numbers of blastocysts obtained in all co-culture systems were significantly higher (P<0.05) compared to those developing in culture medium only. Although the putative mechanism is as yet unexplained, the improved blastocyst formation rates and cell numbers in co-culture when there is direct contact between the embryo and the cell monolayer suggest that the close proximity between the feeder cells and embryos is in part responsible for these effects.     

Land degradation factors in arid irrigated areas: the case of Wafra in Kuwait

A large area in Wafra, south of Kuwait, was developed for crop production both in open fields and agriculture units. For more than a decade, farmers had been using groundwater and desalinated water for irrigating crops under both conditions. The study area occupied about 125 000 ha lying within the northwestern sandbelt. Land-use pattern, soil characteristics and vegetation attributes were studied to assess the extent of land degradation in the area. Land-use classes in the developed area showed a total area of about 9371 ha. About 35 per cent of this area was uncultivated due to sand encroachment and soil salinity build-up problems. Soil chemical and physical properties were described and determined at various depths in representative profiles. The soil belonged to the three categories: Typic Torripsamments, Typic Haplocalcids and Typic Aquisalids. The total vegetative cover was poor, covering about 18 per cent of the marginal areas and about 33 per cent of arable lands. Plant community type was altered from Rhanterium epapposum to Cyperus conglomeratus and Stipagrostis plumosa. Annual forbs dominated species composition. Results of the study indicated that land degradation occurred both in marginal and arable areas. To expand in the Wafra agricultural area and to increase productivity potential of the existing farms, implementation of irrigation and drainage systems as well as projects to combat sand encroachment are recommended. © 1998 John Wiley & Sons, Ltd.