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11.
Shaukat Ali Bhatti Kamran Nazir Muhammad Jamil Basra Muhammad Sajjad Khan Muhammad Sarwar Muhammad Ashraf Iqbal Mughal 《Tropical animal health and production》2013,45(4):923-930
The objective of present study was to evaluate the growth potential of Sahiwal calves for veal production on whole milk or whole milk and milk replacer combined in a ratio of 50:50 (MMR). For this purpose, 48 Sahiwal calves (both male and female) were assigned to four dietary treatments having 12 animals/treatment. Calves in the treatments A and B were offered whole milk at 15 or 20 % of their body weight (BW), respectively, up to day 84 adjusted on weekly basis. The calves in treatments C and D received the same amount of milk as in treatments A and B until day 21, respectively, after which 50 % of the milk offered was replaced with a blend of chickpea (Cicer arietinum) flour and vegetable (corn) oil mixed in water (MR) until day 84. The constituted MR had 3.1, 2.8, and 14.3 %, CP, EE, and DM, respectively. The growth and intake data were analyzed using repeated measures analysis, with MIXED Procedures of SAS in a 2?×?2 factorial design. The two factors were feeding level and feeding source. Calves offered whole milk grew faster (P?<?0.05) and had greater weaning weights (P?<?0.05) than those offered MMR (606.4?±?18.1 vs 331.3?±?18.1 g/day and 70.4?±?1.5 vs 47.8?±?1.5 kg, respectively). Greatest daily BW gain (656?±?26 g/day) and weaning weight (74.6?±?2.1 kg) were observed in calves given treatment B while the lowest production cost/kg of BW gain (≈US$3.6?±?0.2) was observed in calves given treatment A. The daily BW gain of calves fed milk ad libitum was 716?±?40 and 836?±?40 g/day, during 5–8 and 9–12 weeks, respectively. The number of days calves exhibited scours was higher in calves offered MMR than those offered whole milk. Replacement of 50 % milk with a blend of chickpea flour and vegetable oil, as an alternative to milk replacer, did not support growth equivalent to whole milk and was not effective in reducing feeding cost during the weaning period. Sahiwal calves may have promise for being raised for veal production under tropical environments. 相似文献
12.
Pathogenicity of Lecanicillium muscarium, against Eretmocerus sp. nr. furuhashii (Hymenoptera: Aphelinidae), was investigated under laboratory conditions to determine if the fungal infection of the whitefly
host can effect the survival, longevity and fecundity of female parasitoid. The results indicated that the number of parasitized
larvae surviving a L. muscarium treatment after 6 days of oviposition decreased with increasing concentrations of L. muscarium and in later stages of development (12 days post oviposition) were not affected by fungal application. There were no significant
differences on adult parasitoid survivorship after 7 days among all treatments. Maximum survivorship (73.33%) was observed
for control and it was minimum (60%) at 1 × 108 conidia/ml. L. muscarium showed a non significant effect on longevity and next offsprings of female parasitoids. The percentage emergence of parasitoids
from the whitefly nymphs produced by the females emerged from treated pupae was almost similar. Maximum emergence (69.77%)
was observed at 1 × 106 conidia/ml and it was lowest (61.02%) at conidial concentration of 1 × 108 conidia/ml. Maximum longevity of adult Eretmocerus sp. emerging from whitefly nymphs when treated after 12 days of postoviposition was observed for 1 × 105 conidia/ml having a mean value of 5 days whereas the lowest longevity was 4.9 days observed at 1 × 108 conidia/ml. The results mentioned above indicate that the interaction among biocontrol agents is positive to a greater extent
with minimum risk hazards. 相似文献
13.
Two new hetrofunctional triazine based UV absorbers (1a, 2a) were theoretically and experimentally synthesized at our previous work. In the current investigation, these absorbers were applied to woven cotton fabric via the exhaust method of dyeing, that increase the ultraviolet protection factor of fabric by keeping the quantity of finishing chemicals low to combat with the environmental problem. Therefore, a statistical tool central composite rotatable design (CCRD) of response surface methodology (RSM) was selected for process modeling. The CCRD was applied to study the effect of three process variables (salt, alkali and temperature) on the two responses (exhaustion and fixation percentage) and for the evaluation of the interactive effects of the three process variables. The results show that the applied quadratic model was highly significant and fit to the experimental data for both the UV absorbers (1a and 2a). The values of optimized parameters for CCRD, in cotton finishing with newly synthesized UV absorbers (1a and 2a) were respectively as follows; temperature of 61.91 oC, dose of salt 34.28 g/l and dose of alkali 19.82 g/l. Under these conditions, 77.56 (±3) and 76.08 (±3) exhaustion and 81.12 (±3) and 79.23 (±3) fixation percentage obtained for UV absorbers 1a and 2a respectively. The ultraviolet protection factor (UPF) of treated cotton fabric under optimized conditions appeared in very good range. The results reveal that the applied statistical design economically and effectively predicts the optimized conditions of finishing of cotton by keeping the number of experiments low than the one factor at a time method, that ultimately reduce water pollution and wastage of resources. 相似文献
14.
Production and biocontrol efficacy of culture filtrates containing cuticle degrading enzymes from three isolates of Isaria fumosorosea against diamondback moth (Plutella xylostella) was observed during this study. This fungus when cultured in liquid medium having different carbon sources showed maximum
biomass production when 1% chitin was added as carbon source. These isolates when grown in liquid culture conditions having
1% chitin as source produced cuticular degrading enzymes (proteases (Pr1 and Pr2), chitinases, chitosanase, and lipase) in
a sequential manner and the production of these enzymes differed from control. Biocontrol assays with P. xylostella showed that the culture filtrates of I. fumosorosea were potent antifeedants because reduction in the feeding rate and body weight of the larvae was observed. Similarly, reduction
in rates of successful pupation, adult emergence was observed when the culture filtrates were applied topically. At the end
of the test period, the lowest ST50 value (1.57 ± 0.20 days) was recorded for insect groups treated with culture filtrates from isolate IF28.2 when compared
to the control. In view of the need for safer and environmentally friendly pest management tools, the present study can help
in the development of enzyme-based biopesticides against P. xylostella. 相似文献
15.
Savannas worldwide are vital for both socioeconomic and biodiversity values. In these ecosystems, management decisions are based on the perception that wildlife and livestock compete for food, yet there are virtually no experimental data to support this assumption. We examined the effects of wild African ungulates on cattle performance, food intake, and diet quality. Wild ungulates depressed cattle food intake and performance during the dry season (competition) but enhanced cattle diet quality and performance during the wet season (facilitation). These results extend our understanding of the context-dependent-competition-facilitation balance, in general, and are critical for better understanding and managing wildlife-livestock coexistence in human-occupied savanna landscapes. 相似文献
16.
The effects of four host plants (Agave sisalana, Ag. americana var. marginata, Ananas comosus Baili and An. comosus Smooth Cayenne) on the biology of the mealybug Dysmicoccus neobrevipes Beardsley were studied in the laboratory at 26 ± 1 °C, 75-90% RH and 14:10 (L:D) photoperiod. The development, survivorship, longevity, reproduction and life table parameters of D. neobrevipes differed among the host plants. The shortest developmental period (from the first instar nymph to adult) was recorded on An. comosus Smooth Cayenne (22.4 days for females and 21.3 days for males), whereas the longest was recorded on An. comosus Baili (25.6 days for females and 24.7 days for males). The highest survivorship was found on An. comosus Baili (98% for both females and males) and the lowest was on Ag. americana var. marginata (39.6% for females and 50% for males). Meanwhile the sex ratio and fecundity were highest and the pre-lay period was shortest on Ag. sisalana. The longest longevity of females was 62.5 days on An. comosus Baili, whereas the other host plants did not differ significantly with grand mean longevities of 51.0 days for females, while the longest and shortest longevities of males were 4.6 days and 2.3 days on Ag. americana var. marginata and Ag. sisalana, respectively. Values for net reproductive rate, intrinsic rate of increase and finite rate of increase were highest on Ag. sisalana, whereas the mean generation time was shortest on An. comosus Smooth Cayenne. The results indicated that Ag. sisalana is the most suitable host for D. neobrevipes among the four tested plants. When reared on Ag. sisalana, D. neobrevipes had a short developmental period (females 22.7 days and males 23.8 days), high reproduction (418 nymphs/female) and a high intrinsic rate of increase (0.106). Results of this study indicated that host plant can largely influence the population dynamics of D. neobrevipes, and our findings are useful in understanding the roles of host plants in integrated management of this pest, including exploitation of these host plants in push-pull control. 相似文献
17.
Bhatti SA Ahmed MF Wynn PC McGill D Sarwar M Afzal M Ullah E Khan MA Khan MS Bush R Warriach HM Khan A 《Tropical animal health and production》2012,44(4):819-826
The objective was to study the growth potential of Sahiwal calves given milk or milk replacer with or without concentrates. For this purpose, forty-eight Sahiwal calves were divided into four groups of 12 animals each with equal sex ratio. In each group, the calves were offered either milk or a milk replacer (MR) at a rate of 10% of their body weight adjusted weekly. In addition to this, calves were fed either a starter ration plus Egyptian clover hay (SR + H) or hay only (H) until the end of trial. The milk or MR was withdrawn gradually from day 56 until animals were weaned completely by day 84. Calves offered milk grew faster than those offered MR (357 ± 9 vs. 162 ± 9 g/day; p < 0.05) and displayed higher weaning weights (51.6 ± 0.8 vs. 35.2 ± 0.8 kg; p < 0.05). The calves offered SR + H grew faster (311 ± 9 vs. 208 ± 9 g/day; p < 0.05) and displayed higher weaning weights (48.7 ± 0.8 vs. 38.1 ± 0.8 kg; p < 0.05) than those fed H alone. Calves offered milk plus SR + H showed the highest growth rate and weaning weights (401 ± 13 g/day and 56.3 ± 1 kg, respectively). The lowest growth rate and weaning weights were observed in calves offered MR and H only (115 ± 13 g/day and 30.3 ± 1 kg, respectively). Calves offered the MR had higher number of scour days than those offered milk (13.5 vs. 3.3). The feeding of whole milk in combination with the starter ration and hay resulted in superior growth rates, higher weaning weights, and healthier calves than the other feeding regimens. 相似文献
18.
[目的]分析不同温度、pH及培养基对长毛拟青霉[Paecilomyces penicillatus(H?hn)]菌株SP053生长特性的影响,为SP053菌株的大规模发酵及微生物农药的研制与开发提供理论依据.[方法]以SP053菌株为试验材料,采用常规的固体培养方法,分别测试该菌株在6个温度梯度(17、20、23、26、29和32℃)、5个pH(5、6、7、8和9)和3种不同培养基[马铃薯葡萄糖琼脂培养基(PDA)、萨氏培养基(SDAY)和察氏琼脂培养基(Czapek)]等培养条件下的孢子萌发率、菌落生长速率和产孢量.[结果]温度、pH和培养基类型对SP053菌株的生长特性具有明显影响.高温(32℃)和低温(17℃)均不利于SP053菌株生长,23~29℃为该菌株的最适生长温区,在26℃下的孢子萌发率(94.50%)、菌落直径(47.5 mm)和产孢量(4.450×109个孢子/皿)均最高.在26℃下,SP053菌株在PDA和Czapek培养基上生长较快、产孢量较多,培养15 d的菌落直径分别为47.7和46.3 mm,产孢量分别为5.357×109和2.570×109个孢子/皿.pH在7~8时SP053菌株的生长、萌发和产孢效果最佳.[结论]SP053菌株在26℃下、pH为7~8的PDA培养基上的生长和产孢效果最佳. 相似文献
19.
Can ZHANG Zhen-fang SHAO Yue-ye HAN Xing-min WANG Ze-qing WANG Peter Dennis Musa Bao-li QIU Shaukat Ali 《农业科学学报》2018,17(2):389-396
The present study reports the sublethal effects of the entomopathogenic fungus, Aschersonia aleyrodis(Webber) on Bemisia tabaci(Gennadius)(Homoptera: Aleyrodidae). A fungal suspension of A. aleyrodis isolate Aa005 containing 1×107 conidia mL~(–1) was sprayed against B. tabaci on eggplant leaves under greenhouse conditions. The effects of fungal application on survival as well as life table parameters of the whitefly were observed at different post inoculation periods. The results indicated that A. aleyrodis can significantly affect the survival of 1st, 2nd, and 3rd nymphal instars of B. tabaci. Developmental periods of different instar nymphs were not affected by fungal application. A. aleyrodis spores persisted well and significantly affected the survivorship of young instar nymphs of B. tabaci at different post incubation periods. Life table results suggested that A. aleyrodis has no impact on general fecundity and longevity of B. tabaci. When the pathogen was exposed to the open environment and maintained for a relatively longer period, a reduction in the reproductive rate and intrinsic rate of increase was caused by the fungal spores, though the sublethal effects were not as good as the control treatment. The results suggest that the ability of spores to suppress an increase in whitefly population persists well after incubation of spores to the external environment(up to 9 days). 相似文献
20.
Tall fescue (Festuca arundinacea Schreb.) is a cool-season turfgrass used on fairways in golf courses. The object of this study was to develop a more efficient,
reliable, and repeatable approach in transforming the grass using Agrobacterium (EHA105), where β-glucuronidase gene (uidA) was used as a reporter and hygromycin phosphotransferase gene (hyg) as a selectable marker. An effective expression of transgene
was observed in transforming 2-month-old calli derived from mature seeds (cv. Bingo) cultured on MS medium supplemented with
9 mg·L−1 2, 4-D. A two-step solid medium selection with increasing hygromycin concentration (from 30 to 50 mg·L−1) was used to obtain resistant calli. Transgenic plants have been produced from many independent transformed calli. The presence
of functional β-glucuronidase gene (uidA) was detected in hygromycin-resistant calli. Transgenic plants were regenerated and PCR and Southern blot confirmed transgene
integration in the tall fescue genome.
Biography: QIAN Hai-feng (1973–), male, Ph.D., associate professor in Zhejiang University of Technology. 相似文献