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11.
The inheritance of resistance to dry root rot of chickpea caused by Rhizoctonia bataticola was studied. Parental F1 and F2 populations of two resistant and two susceptible parents, along with 49 F1 progenies of one of the resistant × susceptible crosses were rested for their reaction to dry root rot using the blotting-paper technique. All F, plants of the resistant × susceptible crosses were resistant; the F2 generation fitted a 3 resistant: 1 susceptible ratio indicating monogenic inheritance, with resistance dominant over susceptibility. F3 family segregation data confirmed the results. No segregation occurred among the progeny of resistant × resistant and susceptible × susceptible crosses.  相似文献   
12.
The objective of this study was to evaluate the coefficient of total tract apparent digestibility (CTTAD) of dietary nutrients, endogenous fat loss (EFL), dietary metabolizable energy (ME) content, coefficient of true digestibility (CTD) of fat and faecal parameters of dogs. A total of 16 puppies and 8 adult dogs were distributed according to a double Latin square experimental design. A basal diet was formulated, to which increasing levels (60, 120 and 180 g/kg) of poultry offal fat oil were added. EFL was estimated using hyperbolic and linear regression as a function of LW/day and dry matter (DM) intake, respectively, and the CTD of fat was calculated. The CTTAD of acid-hydrolysis ether extract (AHEE) and ME content increased as dietary poultry offal fat level increased both in adult dogs and in puppies (p < .05). The CTTAD of DM and crude protein were higher in adult dogs than in puppies. EFL was estimated by hyperbolic regression as y = 98.1094 − 13.6202/x and y = 99.1280 − 26.1366/x, where y = CTTAD of AHEE (%) and x = AHEE intake/kg BW, for adult dogs and puppies, respectively, which yielded EFL values of 138 and 262 mg AHEE per kg BW per day for adult dogs and puppies respectively. The EFL estimated by linear regression was 7.89 g and 8.97 g/kg DM intake for adult dogs and puppies respectively. The CTD estimated by both methodologies was higher in puppies than in adults (p < .05). Lower faecal DM and score, and higher ammonia production were obtained in puppies than adult dogs (p < .05). The results indicate good fat utilization and that fat digestibility is underestimated, as the CTTAD of AHEE does not take into account EFL, particularly at low-fat inclusion levels and in growing dogs, which have greater EFL than adult dogs.  相似文献   
13.
Biofloc technology based 45-day indoor growth trial was conducted to evaluate the effect of carbohydrate (CHO), molasses supplementation on two developmental stages viz, juvenile (J) and sub-adult (SA) of Penaeus monodon in zero-water exchange system. P. monodon juveniles (1.56 ± 0.04 g) and sub-adults (14.32 ± 0.22 g) were stocked in fibre-reinforced plastic tanks (1,000 L) with soil base. Carbohydrate supplementation significantly reduced (p < 0.05) the total ammonia nitrogen (TAN), nitrite-N (NO2-N) and nitrate-N (NO3-N) over the time periods in sub-adult group. However, no significant difference in TAN and NO2-N was observed in juvenile-based treatments. Supplementation of carbohydrate significantly increased (p < 0.05) the water and soil total heterotrophic bacterial (THB) count in both juvenile and sub-adults. Despite increase in total Vibrio count (TVC), lower TVC/THB % was noticed in the water column of J + CHO (0.82) and SA + CHO (0.73) compared to control groups, J ? CHO (1.48) and SA ? CHO (1.21). Supplementation of carbohydrate increased the final body weight in J + CHO (6.51 ± 0.44 g) and SA + CHO (22.52 ± 0.98 g) compared with respective controls, J ? CHO (5.05 ± 0.45 g) and SA ? CHO (20.00 ± 0.33 g). Similarly, significantly lower (p < 0.05) feed conversion ratio and better protein efficiency ratio were recorded in carbohydrate-supplemented juvenile and sub-adults treatment groups. The present study demonstrates that supplementation of carbohydrate reduced the nitrogenous metabolites and significantly enhanced the growth performance of juvenile and sub-adult of P. monodon.  相似文献   
14.
15.
Stimulation of carotenogenesis in carotenoid producing red yeasts, algae, or bacteria for enhanced carotenoid production has been achieved by mevalonic acid addition. Recently, carotenoid‐enriched feed was produced by Phaffia rhodozyma fermentation of inexpensive animal feeds. Because mevalonate improves carotenoid yield in P. rhodozyma in synthetic medium, this study tested whether a similar enhancement was possible in biobased substrates. Four concentrations, 0, 0.02, 0.04, and 0.1% of mevalonate as a precursor of P. rhodozyma production of astaxanthin and β‐carotene were evaluated in five substrates: defatted rice bran, full fat rice bran, wheat bran, corn whole stillage, and synthetic media. Additionally, four concentrations, 0, 0.05, 0.1, and 0.5% of apple pomace and tomato pomace were also evaluated as precursors of carotenogenesis in P. rhodozyma fermentation of corn whole stillage and rice bran. Mevalonic acid, tomato pomace, and apple pomace enhanced carotenoid yields in all substrates in that order. However, the optimal concentration of precursor and the percent increase of carotenoid yield in each substrate were variable, potentially indicating substrate influence on carotenoid stimulation. Among animal feed substrates, mevalonic acid in corn whole stillage resulted in the best astaxanthin yield of 220 μg/g and β‐carotene of 904 μg/g. Tomato pomace resulted in 29% astaxanthin and β‐carotene enhancement in corn whole stillage, and apple pomace increased β‐carotene production by 26% in whole stillage. The use of expensive mevalonate is offset by the inexpensive process of producing carotenoid‐enriched DDGS. Optimization of tomato or apple pomace addition may further enhance the carotenoid yields.  相似文献   
16.
Carotenoid-enriched distillers dried grain with solubles (DDGS) developed as a value-added animal feed to provide carotenoids from mono and mixed culture (Mx) fermentation of red yeasts Phaffia rhodozyma (PR) and Sporobolomyces roseus (SR) were evaluated for their nutritional composition and compared to the control (C) DDGS. Apart from providing carotenoids, all three fermentation treatments reduced fiber with best reduction of 77% in PR, enhanced crude fat with highest of 81% in Mx, and reduced protein, amino acids and nitrogen by 50% in PR. DDGS fiber reduction by 77% was achieved by P. rhodozyma in the absence of any pretreatment. Qualitative and quantitative differences in fatty acid profiles were seen among the treatments. Vaccenic acid, a monounsaturated fatty acid produced in SR and Mx fermentation, was absent in C and PR. All these nutritional modifications are highly desirable in different DDGS-based animal feeds and can be explored to obtain tailor-made feeds/feed blends for specific animal diets.  相似文献   
17.
Following the prevalent agronomic practice of applying N fertilizer in two splits at optimum levels recommended for maximum yield viz. 120 kg N ha, to two wheat (Triticum aestlvum L.) cultivars, which differ in in vivo nitrate reductase (NR) activity, it was observed that the activity is high in the first formed leaf blades and declines in the successively formed ones. Enhancement in the activity subsequent to incubation of excised leaf blades in NO3 suggests that the substrate (NO 3) is limiting and that the leaf blades, particularly the upper ones, have the potential to reduce additional amounts of NO3 . High NR cultivar has greater potential than the low NR cultivar. The studies suggest that it may be possible to increase the NO3 moles reduced and thus enhance the reduced N content in case the nitrogen is available at later stages of growth.  相似文献   
18.
An epidemiological investigation was done in brackish water culture systems in three coastal districts of West Bengal. A total of 198 farms were randomly surveyed with a structured questionnaire. The data showed that there was a significant difference in outbreak of white spot disease (WSD) (p < 0.01), shell-associated problems (p < 0.01), and gill-associated problems (p < 0.05) among the culture systems. Among all systems, stunted and uneven growth and white fecal disease (only in shrimp monoculture) were the dominant emerging disorders. WSD remained the most prevalent disease. Some farms tested (polymerase chain reaction [PCR]) positive for WSD, but the animals were apparently healthy. Chlorination, use of PCR screening, application of immunostimulants, and strict bio-security measures play major roles in containing disease outbreaks.  相似文献   
19.
The heteropteran bug, Helopeltis theivora is a polyphagous pest attacking the foliage crop tea and several other crops grown in the old world tropics. Application of synthetic insecticides, especially organophosphate was so far an effective and economic means of conventional management of the pest. Severe selection (bottlenecking) of H. theivora population by exposure to LC80 dose of an organophosphate insecticide, monocrotophos resulted in 105 fold increase in tolerance level in the third generation. The total activity of general esterases (GE) and cytochrome P450 mono-oxygenases (CYP450) analogously increased in insecticide-selected F2 generation by 16.4 and 9.5 fold, respectively. Such enhanced enzyme activity could be related to the higher tolerance levels of the selected bug. Electropherogram of GE and CYP450 of the insecticide-selected generations indicated a change in isozyme profile with their elevated expressions. Induced isozymes in insecticide selected generations were only partially inhibited, when blocked by the insecticide. These findings imply that different groups (zones) of isozymes of the detoxifying enzymes are involved in imparting higher tolerance in insecticide-selected generations. Isozyme profiles of defence enzymes can be used as indices for identifying tolerance level in the field population of H. theivora, enabling tea planters to carry out rapid monitoring of the tolerance status of the pest populations, thereby providing a ready clue to choose an effective insecticide for pest management.  相似文献   
20.
The novel pyrene based dye sensor was designed and synthesized through the reaction between pyrene-1-carboxaldehyde and 4-phenylthiosemicarbazide. This dye sensor showed selectivity and sensitivity binding properties toward F? ion with showing absorption and emission changes in DMSO. These optical properties were investigated by using UV-vis spectrometer and emission spectrophotometer. In addition, electron distributions and HOMO/LUMO values of this dye sensor were simulated and calculated with theoretical calculations of Material Studio 4.3.  相似文献   
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