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481.
The effects of sodium selenite (SS) and selenium yeast (SY) alone and in combination (MS) on the selenium (Se) content, antioxidant enzyme activities (AEA), total antioxidant capacity (TAC), and oxidative stability of chicken breast meat were investigated. The results showed that the highest (p < 0.05) glutathione peroxidase (GSH-Px) activity was found in the SS-supplemented chicken breast meat; however, SY and MS treatments significantly increased (p < 0.05) the Se content and the activities of catalase (CAT), total superoxide dismutase (T-SOD), and TAC, but decreased (p < 0.05) the malondialdehyde (MDA) content at 42 days of age. Twelve days of storage at 4 °C decreased (p < 0.05) the activity of the GSH-Px, but CAT, T-SOD, and TAC remained stable. SY decreased the lipid oxidation more effectively in chicken breast meat. It was concluded that SY and MS are more effective than SS in increasing the AEA, TAC, and oxidative stability of chicken breast meat.  相似文献   
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484.

The first objective of the present study was to evaluate if the antibodies induced by the live LaSota and killed Newcastle disease (sub-genotype VIIi) vaccines protect the chickens against exposure with pathogenic avian avulavirus-1 (AAvV-1) of chicken and/or pigeon origins. The second objective was to study the effect of vaccines on stressed birds (dexamethasone, aflatoxin, and heat stressed) with respect to antibody production and protection against pathogenic AAvV-1 challenge. Sixty-one-day-old Hubbard chickens were divided into six groups (gA–gF) with ten animals each. All the groups received LaSota (105 EID50, 0.1 ml per chick) on days 7 and 27 via eye drop and one intramuscular injection of a killed vaccine (sub-genotype VIIi) (107.5 EID50, 1 ml) on day 18, except the control birds received the PBS only. Moreover, group gC-DEX received dexamethasone intramuscularly at a dose rate of 1-mg/kg body weight daily; gD-AFLA had received aflatoxin as oral gavage at a dose rate of 30 ppb daily, and gE-HEAT was kept under heat stressed (38 °C) till challenged. All the groups were challenged with AAvV-1 strain of chicken origin of sub-genotype VIIi, except the group gA-pigeon was challenged with pigeon-origin strain (sub-genotype VIm). The result showed that the gA-pigeon and gB-chicken vaccinate showed 100% and 80% protection. The immunosuppressive birds produced low pre-challenge HI titer, and protection was observed at 40%, 50%, and 70% in gC-DEX, gD-AFLA, and gE-HEAT, respectively. Our findings suggest the stress factors such as aflatoxin in the feed and dexamethasone are immunosuppressive in nature and suppress the immune response and its associated protective role during infection.

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485.
Tropical Animal Health and Production - Sirtuin 4 (SIRT4) belongs to the mitochondrial sirtuin class of NAD+-dependent protein deacylases. This gene plays an important role in the regulation of...  相似文献   
486.
Background: Haemonchosis is a major economic problem in goat production in humid, tropical and subtropical regions. The disease is caused by an abomasal nematode, Haemonchus contortus, which is highly pathogenic in small ruminants. The aim of this study was to identifying single-nucleotide polymorphisms(SNP) that were associated with fecal egg counts(FEC) and could be used as markers to identify resistance to H. contortus in goats.Results: Ten novel variants in the CI TA, ATP2 A3, HSPA8, STAT5 B, ESYT1, and SERPING1 genes were associated with FEC in goats with a nominal significance level of P 0.05. Two missense mutation in the exon region of the caprine CI TA gene resulted in replacement of arginine with cysteine at position 9473550(R9473550 C) and aspartic acid with glutamic acid at position 9473870(D9473870 E). Chinese goat breeds had significantly higher FEC than Bangladeshi goat breeds within their respective genotypes. Polymorphism information content(PIC), effective al ele number(Ne), and heterozygosity(He)were greatest for the STAT5 B_197_A G SNP locus in al goat breeds. Pairwise coefficients of linkage disequilibrium(D′, r~2)revealed complete LD(r~2= 1) between significant SNP polymorphisms in CI TA and SERPING1 and strong LD(r~2= 0.93 and0.98) between polymorphisms in HSPA8 and ATP2 A3, respectively. Correlation coefficient(r) between FEC and body weight(BW) was significantly positive(r = 0.56***, P 0.001) but that between FEC and packed cel volume(PCV) was negatively significant(r =-0.47**, P 0.01) in the total population of goats. On the other hand, correlation coefficient(r)between BW and PCV was not significant in total population of goats. Association analysis revealed that haplotypes within ATP2 A3, HSPA8, and SERPING1 were significantly associated with FEC. Quantitative real-time PCR revealed that the relative expression of m RNA was higher(P 0.001) for resistant, compared to susceptible, groups of goats for al candidate genes except CI TA.Conclusions: This study identified SNP markers that can potential y be used in marker-assisted selection programs to develop goat breeds that are resistant to H. contortus.  相似文献   
487.
This paper provides an overview of the issues in and approaches to measuring and enhancing the value of agricultural water in large irrigated river basins. It develops a framework and a set of indicators for valuing agricultural water by looking into various dimensions and underlying key factors that influence the value of water at micro, meso and macro levels. The indicators are applied to recent, primary- and secondary-level empirical data from the Indus basin Irrigation system of Pakistan. In addition, the paper compiles recent estimates of the value of agricultural water from 40 settings in 23 countries. Finally, the paper outlines measures for enhancing the value of agricultural water. The paper makes four main points: (1) The popular productivity indicators based on crop output do not capture the full range of benefits and costs associated with agricultural water use. (2) The value of agricultural water may not be as low as it is generally perceived or estimated when all major uses and direct and indirect benefits of water at various levels are properly accounted for. (3) The value of water varies across time and space, and the value to stakeholders at various scales (farmer, system manager, basin planner and national policy maker) could be quite different. For example, the estimate of agricultural water value in the upper Indus basin in Pakistan varies from US$0.04/m3 at the farm scale to US$0.22/m3 at the national scale. The farm-scale value is more relevant, e.g., for agricultural water charging policies, but for water-sector investments and allocation decisions, the national-scale value is important. The decision-making processes related to water sector investments, allocations, management, and charging/cost recovery schemes could be potentially misguided if key dimensions of water value that are related to water availability and use, benefits/costs, and temporal and spatial aspects are not properly accounted for in valuation. (4) Efforts should be directed not only at increasing the productivity of water in terms of mass of output per unit of water, but also the overall benefits or value of water at various levels for larger growth and poverty alleviation impacts, considering the sustainability of the systems.
Intizar HussainEmail:
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488.
In the present investigation, different strains of Plant growth-promoting rhizobacteria (PGPR), namely Bacillus megaterium, Pseudomonas fluorescens and Bacillus subtilis were evaluated for their growth-promoting effects on wheat as well as on soil properties under field conditions at two different sites having sandy loam and silt loam type of soils. PGPR strains were evaluated either singly or in consortia. Amongst all the treatments, wheat inoculated with consortia was found most effective as it increased grain yield up to 53% over control in silt loam soil, whereas, corresponding effects in sandy loam soil were less pronounced as an increase of 31% was observed in corresponding treatments, respectively. Enhanced effects on soil properties were also more intense in silt loam as there was an increase of 205% organic matter as against sandy loam soil where this value was 110%.  相似文献   
489.
Abstract

Implementation of proper management practices using biological approaches is important to maintain soil quality and cotton yield in sandy desert soils of Egypt. This experiment was conducted at the Agriculture Experimental farm, Kafer El-Sheikh governorate, Cotton Research Institute of Egypt during 2016–2017 seasons to study the effect of inoculation with bacterial strains of Bacillus circulance (BC) and Bacillus megatherium (BM) and their co-inoculation in combinations with 50% and 100% of recommended dose fertilization (RDF) on growth, yield, and fiber properties of Egyptian cotton Giza-94. Results showed that all important morphological attributes of cotton such as plant growth, number of fruit sympodial branches, number of bolls per plant, boll weight, lint cotton yield and fiber properties significantly increased with the increase rate of RDF, and inoculation of cotton seeds with the bacterial strains exerted additive effects. The highest increase of cotton yield was observed at the combined use of bacterial strains BC?+?BM with 50% RDF followed by BC?+?BM with 100% RDF treatment which attributed on the cotton yield increase by 33% and 15% compared to the respective control. The application of Bacillus strains as a biofertilizer could be an alternative option to reduce considerable amounts of chemical fertilizers input by enhancing nutrient use efficiency (NUE) and, thereby, improves cotton productivity.  相似文献   
490.
An investigation was conducted to determine the trace- mineral concentrations of forages in relation to requirements of ruminants grazing in natural pastures in the province of Punjab, Pakistan during two different seasons. Animals were closely followed during grazing and forages corresponding to those consumed by the animals were taken and analyzed for copper (Cu), iron (Fe), zinc (Zn), manganese (Mn), and cobalt (Co) concentrations. The data on the trace- mineral concentrations showed that most of these minerals varied greatly as a function of seasons and sampling periods. The forage Cu, Fe, and Zn concentrations were affected by seasonal changes but no influence of season was observed on the concentrations of forage Mn and Co concentration. Forage Zn and Co, during both seasons and at some sampling intervals, and forage Mn during summer were at marginal deficient levels, and in contrast, all other forage trace-minerals were within the required range for ruminants during both seasons. Based on these results, the supplementation of Zn, Co, and Mn would seem most important to support optimum livestock productivity.  相似文献   
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