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51.

Fungal toxins in feed are leading issue in poultry industry causing a detrimental effect on the performance and health of poultry. The study was carried out to determine the incidence and concentration of the aflatoxins and their major producer Aspergillus flavus in home mix layer poultry feed in respect of seasonal variation throughout the year. A total of (n?= 204) home mix poultry layer feed samples were analyzed for the isolation of fungi. The isolates were initially screened through colony morphology and microscopic examination. However, aflatoxin concentration was determined by ELISA. Revealed results indicated that, the highest percentage of A. flavus was found during the months of June to August 50/54 (92.5%) followed by September to November 43/65 (66.1%), March to May 21/40 (52.5%), and December to February 18/45 (40%). As a whole, the incidence was recorded 132/204 (64.7%). Moreover, of the 132 samples, 41 (31%) were exceeded in respect of aflatoxin contamination from the legal limit (20 μg/kg) imposed by Food Drug Association (FDA). Statistically, the growth of A. flavus and aflatoxin production was found significantly different in respect of seasonal variation. As highest total viable fungal count (9.9?×?104 CFU/g) and aflatoxin level (72.27 μg/kg) were recorded during the months of June to August and lowest in December to February. Consequently, instantaneous essential control measures are demanded regarding appropriate storage and adequate drying in post-harvesting season. Along with surveillance plans and austere regulations for monitoring the aflatoxin contents for the wellbeing of consumers.

  相似文献   
52.
Tropical Animal Health and Production - Poor quality feed and lack of feed resource conservation in Pakistan are the major constraints influencing livestock production systems in the country. In...  相似文献   
53.
The core objective of the present investigation was to isolate and quantify antioxidants from mosambi (sweet orange) peel. In the proposed research, different solvents were used for the extraction of antioxidants from mosambi peel. Among these solvents, ethanol resulted in better antioxidant yield compared to aqueous extract. Ethanolic extract of mosambi peel showed higher total phenolic contents (19.3 ± 0.3 mg/g) as compared to aqueous extracts (18.2 ± 0.04 mg/g). Considering the safety health concern, aqueous extract of mosambi peel was incorporated in cookies at different concentrations of 1%, 2%, and 3%, and further subjected to physico-chemical and sensory attributes. Proximate composition (moisture, crude protein, crude fat, crude fiber, ash, and niitrogen-free extract (NFE) contents) of fortified cookies varied non-significantly. However, sensory evaluation rated aqueous extract of mosambi peel (2%) with better hedonic response. Mosambi peel antioxidants have a great potential to be used in various functional foods and the ability to improve storage stability.  相似文献   
54.
A four-year tillage experiment on maize was conducted in the high latitude region of Northeast of China. The main objective of this study was to investigate the effects of different field tillage practices on maize grain yield, soil physical properties, and soil water and temperature dynamics in Northeast of China. The tillage practices included moldboard plow tillage (MOT), rotary tillage (ROT), reduced tillage (RET), combined tillage (COT), and no tillage (NOT). The surface soil water content at depths of 0–20 cm was higher under NOT compared with other tillage practices, but not different at the deeper soil depths in 2011. The soil temperatures under NOT and RET were lower than those under moldboard plow tillage and ROT at depths of 5 and 15 cm, respectively, measured at 9:00 am in 2005. From the hourly dynamics of soil temperature, the differences among the tillage practices mainly appeared during the daytime (from 8:00 am to 7:00 pm). Among all the practices, the average daily soil temperature under ROT was the highest, while that under NOT was the lowest. MOT, ROT, and RET had higher soil accumulative infiltration compared with NOT and COT. The surface soil bulk density under NOT was higher than or equal to that under the other four tillage practices. The maize yields under NOT were the lowest among all the tillage practices for three years straight. Meanwhile, the yields under MOT were the highest, which were about 47%, 61%, and 38% higher than those under NOT. NOT practice is not recommended for use in spring-planted maize under the high latitude humid cool climate Mollisol region in Northeast of China.  相似文献   
55.
This study investigated whether the exogenous application of glycine betaine (GB) could alleviate the adverse effects of water deficit on sunflower. Two sunflower lines, Gulshan-98 and Suncross, were subjected to water deficit at the vegetative or the reproductive stages of plant growth. Three levels (0, 50 and 100 mmol l−1) of GB were applied as a pre-sowing seed treatment or as a foliar spray at the time of initiation of water deficit at the vegetative or reproductive stages. Foliar application of GB at the time of initiation of water deficit treatments showed a marginal increase in shoot biomass in drought-stressed plants. Exogenously supplied GB as a foliar spray also showed a positive role in reducing the effects of water deficit on net CO2 assimilation rate, transpiration rate and sub-stomatal CO2 concentration in both sunflower lines. Pre-sowing seed treatment with GB had no effects on the above-mentioned physiological and growth attributes in both normally irrigated and drought-stressed plants. Taken together, foliar application of GB increased net CO2 assimilation rate which in turn showed a slight increase in growth of water-stressed plants but this increase was not related to stomatal regulation.  相似文献   
56.
We identified clinical disorders of all 200 city-dwelling cart pulling male camels attending the Veterinary Teaching Hospital, University of Agriculture, Faisalabad, Pakistan during a 7-year period (1993–1999). Data were collected prospectively on a predesigned form and collated. Diagnoses of different diseases/disorders were based on clinical examination supplemented with relevant laboratory tests. A total of 463 entries of 34 different clinical diseases/disorders were recorded. Sarcoptic mange (35% of 200 camels) followed by anhidrosis (23%) and trypanosomosis (19%) were the three most frequently encountered disorders. The body system most often involved was the integument (31%) followed by gastrointestinal (21%), locomotory (12%), thermoregulatory (6%), blood (6%), urogenital (6%), lymphatic (3%), nervous (3%), respiratory (3%) and ocular (3%).  相似文献   
57.
To study the evolution of recombination rates in apes, we developed methodology to construct a fine-scale genetic map from high-throughput sequence data from 10 Western chimpanzees, Pan troglodytes verus. Compared to the human genetic map, broad-scale recombination rates tend to be conserved, but with exceptions, particularly in regions of chromosomal rearrangements and around the site of ancestral fusion in human chromosome 2. At fine scales, chimpanzee recombination is dominated by hotspots, which show no overlap with those of humans even though rates are similarly elevated around CpG islands and decreased within genes. The hotspot-specifying protein PRDM9 shows extensive variation among Western chimpanzees, and there is little evidence that any sequence motifs are enriched in hotspots. The contrasting locations of hotspots provide a natural experiment, which demonstrates the impact of recombination on base composition.  相似文献   
58.
The anti-tick efficacy of combined aqueous herbal extracts of Azadirachta indica leaves, Nicotiana tabacum leaves, Calotropis procera flowers and Trachyspermum ammi seeds was evaluated using adult immersion test, larval packet test and ear bag method. The extract exhibited lethal effects on egg laying (index of egg laying=0.371404±0.00435), hatching (22.35%) and total larval mortality at 50 mg ml(-1) and reduced tick intensity on the infested calves (18 detached out of 35 at 45% (w/w) suspension, topically applied). The herbal extract exerted dose- and time-dependent response against all the developmental stages of Rhipicephalus (Boophilus) microplus considered in this study, thus justified their use in the traditional system of Pakistan.  相似文献   
59.
Inoculation of Nicotiana benthamiana leaves with virulent and avirulent strains of Pseudomonas syringae pv. tabaci resulted in increasing changes in Fv/Fm, and NPQ over time. Images of these chlorophyll a fluorescence measurements revealed different changes in different zones of the leaf. For the virulent strain, the infiltrated zone and zone directly surrounding it showed decreased Fv/Fm, and NPQ before the appearance of visible symptoms, and these decreases corresponded with increasing bacterial populations and putative tabtoxin activity. Another distinct zone of reduced Fv/Fm and NPQ extended several centimetres from the lesion to the nearest leaf margin, but only very low bacterial populations and no putative tabtoxin activity were detected in this zone. For the avirulent strain, a hypersensitive response occurred, bacterial populations remained low, and there was little detectable putative tabtoxin activity. Decreased Fv/Fm and NPQ, but not , were observed in the infiltrated zone prior to the hypersensitive response, followed by decreased values in a zone directly surrounding it. Following that, no further changes were observed. These results demonstrate that in addition to detecting pre‐symptomatic impacts of bacteria, chlorophyll a fluorescence imaging can also show that there are highly distinct regions of affected tissue that can extend considerably beyond the area of bacterial colonization. This should be considered in selecting leaf tissues for examining the effects of pathogens on plants, such as altered host gene expression or protein levels.  相似文献   
60.

Background  

Genome analysis of soybean (Glycine max L.) has been complicated by its paleo-autopolyploid nature and conserved homeologous regions. Landmarks of expressed sequence tags (ESTs) located within a minimum tile path (MTP) of contiguous (contig) bacterial artificial chromosome (BAC) clones or radiation hybrid set can identify stress and defense related gene rich regions in the genome. A physical map of about 2,800 contigs and MTPs of 8,064 BAC clones encompass the soybean genome. That genome is being sequenced by whole genome shotgun methods so that reliable estimates of gene family size and gene locations will provide a useful tool for finishing. The aims here were to develop methods to anchor plant defense- and stress-related gene paralogues on the MTP derived from the soybean physical map, to identify gene rich regions and to correlate those with QTL for disease resistance.  相似文献   
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