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101.
ABSTRACT

1. The aim of this study was to determine the nutritional status of backyard chickens reared under 4 different agro-climatic conditions (tropical, humid subtropical, cool-temperate and semi-arid) of India during different seasons of the year and to compare their nutritional status with those reared under confined feeding system (CFS). In each season, 15 adult and 15 grower chickens were slaughtered for collecting content of crop and gizzard to assess the nutritional status from different agro-climatic conditions.

2. The dry matter content of crop and gizzard was higher (P < 0.01) in chickens reared under backyard conditions compared to those reared under CFS.

3. Higher (P < 0.01) crop and gizzard contents were recorded during winter compared to the rainy season. The proportion of grains in the crop during summer and winter season was higher compared to rainy season. Further, there were more insects present in the crop during the rainy season and winter compared to summer.

4. The proportion of insects was higher in chickens reared in humid, subtropical and cool temperate regions compared to semi-arid conditions. The consumption of grasses was higher in cool-temperate regions as compared to those reared under other areas.

5. Crude protein (CP), Ca, P and gross energy (GE) content of the crop were higher in chickens reared under CFS compared to those reared in backyard systems and CP in the crop contents was lower in backyard chickens reared in humid subtropical and semi-arid regions compared to other areas. Similarly, lower (P < 0.01) Ca levels were seen in crop and gizzard contents from birds reared in semi-arid Rajasthan, and P and GE were lower in tropical wet and dry Telangana (TWT) compared to the chickens reared in the backyard conditions in other regions.

6. Based on the results, the nutrient intake for birds utilising the scavenging feed resource base (SFRB) in the TWT region was below the requirements of backyard chickens from the other regions selected in the present study. GE and CP were critically deficient in the SFRB of the TWT region. Therefore, evolving location-specific supplementary diets using locally available feed resources to meet nutrient requirement of backyard chickens is required for optimising production potential.  相似文献   
102.
The effects of Nano-clay content on delamination factor during drilling operation on fiber-reinforced composites are optimized through Response Surface Methodology (RSM). Drilling is one of the basic operations on assembly section in many industries. In present work, the experiments are conducted by Box-Behnken Design (BBD) by RSM techniques, which is used to study influential factor on drilling process parameters such as cutting speed, feed rate, size of drill and Nano-clay. The analysis of variance (ANOVA) techniques are employed to evaluation of impact of process parameters on delamination. Developed regression models analyze the interaction properties of process parameters. In addition, the Gray Relational Analysis (GRA) is used to identify the best level of factors for both responses (Entry and Exit condition) to make quality of hole on composites. The experimental result shows that, the feed rate is the most significant factor among the other parameters. The delamination factor is decreased with addition of Nano-clay content at a certain percentile. Furthermore, of Nano-clay content, delamination factor may be increased. The proper propagation of filler content produces a high bonding between the fiber and matrix materials. Hence, the delamination factor may be decreased.  相似文献   
103.
A study was undertaken to determine the free-living culturable diazotrophic bacteria of paddy soils from a long-term fertilizer management experiment. Long-term application of different fertilizers significantly affected the population of free-living diazotrophs. Out of 165 distinct bacterial morphotypes observed during the isolation process, only 32 were positive for both acetylene reduction assay (ARA), and nifH gene screening. The ARA activity of the isolates ranged from 1.8 to 2,844.7 nmol ethylene h?1 mg protein?1. The 16S rRNA analysis identified the isolates to be members of 13 different genera viz. Bacillus, Pseudomonas, Paenibacillus, Serratia, Ochrobactrum, Lysinibacillus, Burkholderia, Brevundimonas, Herbaspirillum, Novosphingobium, Sphingomonas, Xanthomonas, and Azorhizobium. Though partial nifH gene sequencing of diazotrophic isolates showed good consistency with that of 16S rRNA-based identification, some nifH sequences were similar to a variety of uncultured nitrogen-fixing bacteria. The diversity of free-living diazotrophic bacteria and the wide distribution of nifH sequences indicate the potential contribution of these microorganisms to nitrogen input to paddy fields.  相似文献   
104.
Infection with gastrointestinal nematodes (GIN), particularly Haemonchus contortus, is the biggest constraint to profitable goat production in the United States (US). Due to widespread prevalence of anthelmintic resistance in goat GIN, alternative, non-chemical control methodologies are needed to increase profitability of small ruminant industries. A study was designed to test the efficacy of a high condensed tannin (CT) legume, sericea lespedeza [SL, Lespedeza cuneata (Dum.-Cours. G. Don)] against GIN of goats fed in confinement. The goats were given a trickle infection of 500 H. contortus larvae/animal three times per week during the trial to simulate natural infection. Twenty Boer bucks (6-8 months old) were fed bermudagrass [BG, Cynodon dactylon (L.) Pers.] hay plus concentrate for 5 weeks in confinement and then 10 animals were switched to SL hay for an additional 7 weeks. Throughout the trial, feces and blood were collected weekly from individual animals to determine fecal egg count (FEC) and blood packed cell volume (PCV). Fecal cultures were made weekly from pooled samples to determine treatment effects on GIN larval development. All goats were slaughtered at the end of the trial, with adult worms in the abomasum and small intestine of each goat recovered, counted, and identified to species. Feeding SL hay to goats significantly (P<0.01) reduced FEC and increased PCV compared with BG hay. In addition, a lower percentage of ova in feces from SL-fed goats developed into infective (L3) larvae. There was a direct effect of SL hay on adult worms, with significantly (P<0.01) lower numbers of both abomasal (H. contortus, Teladorsagia circumcincta) and small intestinal (Trichostrongylus colubriformis) nematodes compared with goats fed BG hay. Feeding SL hay to goats is an effective means of controlling parasitic nematodes and may be a potential supplement/replacement for chemical anthelmintics.  相似文献   
105.
Falandysz  J.  Brzostowski  A.  Kawano  M.  Kannan  K.  Puzyn  T.  Lipka  K. 《Water, air, and soil pollution》2003,148(1-4):127-137
Fourteen species of wild growing mushrooms and surface (0–10 cm) soils were collected near Lake Wdzydze in the northern part of Poland in 1996–1997 to understand the status of mercury pollution. Concentrations of mercury in mushrooms varied between 100±30 and 2400±1900 ng g-1 dry matter in caps and 60±1 and 1300±1500 ng g-1 dry matter in stalks. Concentrations of mercury in underlying soil were between 30±1 and 140±120 ng g-1 dry matter (between 36±18 and 63±100 ng g-1 depending on the soil type). Bioconcentration factors (BCF: concentrations in mushroom/concentrationin soil) of total mercury were between 2.3±1.1 and 90±110 for caps, and between 2.1±1.0 and 53±56 for stalks. Scaly tooth (Sarcodon imbricatum) contained the greatest concentrations of mercury in the flesh. However, there was no significant relationship (p >: 0.05) between mercury content in the fruiting bodies of this speciesto soil mercury concentrations. A significant (p < 0.01) positive relationship between mercury content in caps to underlying soil was noted for European cow bolete (Suillus bovinus), while a negative relationship between mercury content in caps and stalks to underlying soil was observed for Sandy knight-cap (Tricholomaflavovirens), Shaggy scale-head (Pholiota squaroso-adiposa),Gypsy mushroom (Rozites caperata) and Pine spike cap (Chroogomphus rutilus).  相似文献   
106.
Grazing animals recycle a large fraction of ingested C and N within a pasture ecosystem, but the redistribution of C and N via animal excreta is often heterogeneous, being highest in stock camping areas, i.e., near shade and watering sources. This non-uniform distribution of animal excreta may modify soil physical and chemical attributes, and likely affect microbial community eco-physiology and soil N cycling. We determined microbial population size, activity, N mineralization, and nitrification in areas of a pasture with different intensity of animal excretal deposits (i.e., stock camping, open grazing and non-grazing areas). The pasture was cropped with coastal bermudagrass (Cynodon dactylon L.) and subjected to grazing by cattle for 4 y. Soil microbial biomass, activity and N transformations were significantly higher at 0-5 cm than at 5-15 cm soil depth, and the impacts of heterogeneous distribution of animal excreta were more pronounced in the uppermost soil layer. Microbial biomass, activity and potential net N mineralization were greater in stock camping areas and were significantly correlated (r2≈0.50, P<0.05) with the associated changes in total soil C and N. However, gross N mineralization and nitrification potential tended to be lower in stock camping areas than in the open grazing areas. The lower gross N mineralization, combined with greater net N mineralization in stock camping areas, implied that microbial N immobilization was lower in those areas than in the other areas. This negative association between microbial N immobilization and soil C is inconsistent with a bulk of publications showing that microbial N immobilization was positively related to the amount of soil C. We hypothesized that the negative correlation was due to microbial direct utilization of soluble organic N and/or changes in microbial community composition towards active fungi dominance in stock camping areas.  相似文献   
107.
108.
Six sorghum (Sorghum vulqaris Pers.,) varieties representing male and female lines and hybrids were examined for their response to Fe‐stress, and their ability to absorb and transport Fe in the absence and presence of phosphate or CaCO,. It was found that the variety 2077‐A (male sterile female line) and the variety CSH‐5 (hybrid of 2077‐A r CS‐3541) showed distinct mechanism to tolerate and recover completely from chlorosis induced by Fe‐stress in 10 days. Furthermore, these 2 varieties were able to reduce the pH from 6.4 to 3.8 in about 9 days, and this was increased to about 6.2 in another 6 days, which period corresponded with the onset of chlorosis and subsequent recovery. The variety 2219‐A (male‐sterile female line) was also able to withstand Fe‐stress, although the chlorosis appeared only mild throughout. This variety also reduced pH from 6.4 to 4.5, but only after 14 days in the presence of CaCO3 (8 mg/1), and this time corresponded to the period of complete recovery from chlorosis.

There appears to be no correlation between Fe uptake capacity and tolerance to Fe‐stress in these varieties. The presence of phosphate or CaCO3 in the absorption medium was found to increase Fe absorption and transport in a few varieties.  相似文献   
109.
It has been established that the plant leaves and other above‐ground parts are capable of absorbing chemicals and nutrients. However, there is great paucity of information regarding the mechanisms of ion uptake by leaves and their transport to other parts. Equally not well understood is the phenomenon of retranslocation of elements from one leaf to another during the different stages of plant growth. The results of investigations carried out in this area of foliar uptake and translocation in the last few years are described. In this review, the importance of future studies to investigate the mechanisms involved in foliar transport, the influence of plant growth substances, and the effectiveness of timely supply of specific nutrients during the grain development stage, is stressed.  相似文献   
110.
The effects of Zn‐stress on pH of the nutrient medium and the occurrence of Zn deficiency symptoms were examined in 12 cotton and 10 peanut cultivars widely grown in several parts of India. It was found that many of the cotton cultivars were able to reduce the pH, but however unable to recover from Zn deficiency. In contrast, all the peanut cultivars tested did not develop Zn‐chlorosis when subjected to Zn‐stress, although the pH reduction was less significant. The study with these crop cultivars revealed that Zn‐stress tolerance response was not related to pH changes in general. The mechanism by which the peanut cultivars made Zn available and thus averted the onset of Zn‐chlorosis was therefore not adaptive to the changes in pH. This feature appeared to be different from the pattern of correlative pH reduction and recovery from Fe‐chlorosis observed in several Fe‐stress tolerant crop cultivars.  相似文献   
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