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111.
112.
《The Journal of Applied Poultry Research》2008,17(2):202-210
The use of subtherapeutic levels of antibiotics in poultry feed improves performance and morbidity in broiler chickens. However, consumer pressure related to the potential development of antibiotic-resistant bacteria has resulted in the development of nonantibiotic feed additives that may also improve broiler performance. Essential oils, organic acids, and phytogenic compounds enhance production of gastric secretions, stimulate blood circulation, and reduce levels of pathogenic bacteria. The objective of the current study was to assess the use of Biostrong 505+ and Biostrong 510 as natural growth promoters in broiler chickens. Assessment was based on the performance and carcass quality of broilers fed either a maximum-yield or a least-cost commercial broiler diet. The maximum-yield diet improved broiler performance and carcass quality. Biostrong 505+ can be used to improve feed conversion and breast yield when incorporated into diets devoid of antibiotics. This improvement in feed conversion and breast yield was accentuated when Biostrong 505+ was used in conjunction with a maximum-yield diet. Biostrong 510 improved feed conversion when used in poultry diets containing antibiotics. 相似文献
113.
Kelly C. Nunes Cinthia Eyng Paula T. M. Pintro Rodrigo G. Garcia Alice E. Murakami Ana C. P. Vital Ricardo V. Nunes Patricia O. Nesello 《Journal of animal physiology and animal nutrition》2019,103(1):64-71
The aim of this study was to evaluate dietary supplementation of different levels of dehydrated bocaiuva pulp (DBP) on the productive performance of laying quails, and on lipid oxidation, and quality in their eggs. A total of 120 quails were distributed in a completely randomized design with six treatments (0%, 0.1%, 0.2%, 0.3%, 0.4% and 0.5% of DBP), five replicates and four birds per experimental unit. To evaluate lipid oxidation, the eggs were collected on five consecutive days at the end of the trial and distributed in a completely randomized experimental design in a 6 × 5 factorial scheme (eggs from quails fed different levels of DBP × evaluated fresh and after 7, 14, 21 and 28 days). The antioxidant potential of diets was improved (p < 0.05) when the DBP was added estimated as 2,2'‐azinobis‐3‐ethylbenzothiazolin‐6‐sulfonic acid (ABTS) free radical scavenging capacity. No effect (p > 0.05) was observed on feed intake, hen‐day egg production and feed conversion (kg/kg and kg/dz). There were no changes (p > 0.05) in the egg weight, Haugh unit, yolk index or eggshell percentage. Although no difference was observed (p > 0.05), when comparing each level with the control, a negative linear effect (p < 0.05) on specific gravity was observed. In addition, only the treatment with 0.5% pulp exhibited lower (p < 0.05) eggshell thickness compared with the control (0%). Thiobarbituric acid reactive substances (TBARS) analysis showed that as the dietary pulp level was increased, malondialdehyde content decreased linearly (p < 0.05) in the egg yolks, regardless of the storage period. Inclusion of DBP in the diets had no effect (p > 0.05) on the concentration of conjugated dienes in the eggs. The diets containing DBP showed a potential antioxidant effect, reducing the degree of lipid oxidation in egg yolk. However, no beneficial effects were observed on performance and egg quality. 相似文献
114.
Kirtland’s warblers (Dendroica kirtlandii) persist in a naturally patchy environment of young, regenerating jack pine forests (i.e., 5–23 years old) created after
wildfires and human logging activities. We examined how changing landscape structure from 26 years of forest management and
wildfire disturbances influenced population size and spatial dispersion of male Kirtland’s warblers within their restricted
breeding range in northern Lower Michigan, USA. The male Kirtland’s warbler population was six times larger in 2004 (1,322)
compared to 1979 (205); the change was nonlinear with 1987 and 1994 identified as significant points of change. In 1987, the
population trend began increasing after a slowly declining trend prior to 1987, and the rate of increase appeared to slow
after 1994. Total amount of suitable habitat and the relative area of wildfire-regenerated habitat were the most important
factors explaining population trend. Suitable habitat increased 149% primarily due to increasing plantations from forest management.
The relative amount and location of wildfire-regenerated habitat modified the distribution of males among various habitat
types, and the spatial variation in their abundance across the primary breeding range. These findings indicate that the Kirtland’s
warbler male population shifted its use of habitat types temporally and spatially as the population increased and as the relative
availability of habitats changed through time. We demonstrate that researchers and managers need to consider not only habitat
quality, but the temporal and the spatial context of habitat availability and population levels when making habitat restoration
decisions. 相似文献
115.
Randomized control trial to test the effect of a feed additive on Campylobacter contamination in commercial broiler flocks up to slaughter
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A. Huneau‐Salaün M. Guyard‐Nicodème G. Benzoni X. Gautier S. Quesne T. Poëzevara M. Chemaly 《Zoonoses and public health》2018,65(4):404-411
A randomized controlled trial (RCT) was carried to evaluate the effect of a feed additive on Campylobacter contamination of broilers reared in commercial conditions. Twenty‐four broiler flocks naturally contaminated with Campylobacter were enrolled in the RCT: 12 were assigned to a control group (C) fed with a conventional finishing feed from 4 weeks of age to slaughter (around 35 days), and the other group of 12 flocks (S) was fed with a finishing feed supplemented with 250 ppm of a patented feed additive (an ion‐exchanged clay compound) previously proven to reduce Campylobacter contamination in broiler caeca under experimental conditions. Enumeration of Campylobacter colonies in caeca (8 per flock) was carried out following ISO standards before feed distribution and at slaughter. Before treatment, the caecal Campylobacter load tended to be lower in C flocks (7.1 ± 1.9 log CFU/g, CI95% [6.6–7.5]) than in S flocks (7.7 ± 1.0 log UFC/g, CI95% [7.5–7.9]) (p = .05). At slaughter, the bacterial load was similar in the S (7.7 ± 1.0 log CFU/g, CI95% [7.5–7.9]) and C groups (7.5 ± 1.2 log CFU/g, CI95% [7.2–7.8]) (p = .73). Therefore, the feed additive had no significant effect on the caecal Campylobacter load at slaughter under the tested conditions. The logistical constraints inherent in field trials and the natural variability of Campylobacter contamination in naturally infected broiler flocks make it difficult to reproduce experimental results in in situ farm conditions. RCT testing of an intervention strategy in commercial situation is therefore a key step in evaluating pre‐harvest interventions against food‐borne pathogens. 相似文献
116.
Twenty doubled haploid broccoli lines from breeding material were evaluated for resistance to Peronospora parasitica at the seedling stage. All lines supported sporulation of the pathogen but to varying extents and intensities. Partial resistance of the more resistant lines,‘br8’and ‘br9′, reduced conidia production on cotyledons by 50-70% compared with the most susceptible lines. Inoculation of the two most resistant lines with 13 isolates of different geographical origins revealed that ‘br9′, showed a rather uniform level of resistance to all isolates while ‘br8’showed some isolate specificity Partial resistance was evaluated in six of the broccoli lines in a half diallel set of crosses. Disease assessment of seedlings showed that additive genetic effects explained 45.8% and 31.8% of the total variation of sporulation score and conidia production, respectively This suggests that recurrent selection for partial resistance to P. parasitica in early generation in breds or in populations of broccoli will be efficient to obtain cotyledon resistance. 相似文献
117.
118.
林海琳 《仲恺农业技术学院学报》1998,11(3):10-13
主要介绍饲料添加剂预混料中维生素鉴别方法的改进及其它简便方法,详细描述了操作过程、反应现象及须注意要点改进后的方法克服了用国标法鉴别预混料中多种维生素时常遇到的干扰大、反应现象不明显等难题,大大减少了误判、错判的现象,且具有准确、快速、实用性强等优点 相似文献
119.
益生素在欧鳗养殖中的应用试验 总被引:1,自引:1,他引:0
在欧鳗日粮中添加2‰益生素饲料添加剂,其增重率试验组比空白对照组高出9个百分点,饲料效率试验组比空白对照组高出7个百分点。 相似文献
120.
Aloysia triphylla essential oil as food additive for Rhamdia quelen – Stress and antioxidant parameters
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![点击此处可从《Aquaculture Nutrition》网站下载免费的PDF全文](/ch/ext_images/free.gif)
C.C. Zeppenfeld E.M.H. Saccol T.S. Pês J. Salbego G. Koakoski A.C. dos Santos B.M. Heinzmann M.A. da Cunha L.J.G. Barcellos M.A. Pavanato B.O. Caron B. Baldisserotto 《Aquaculture Nutrition》2017,23(6):1362-1367
We examined the effects of dietary supplementation for 21 days with different levels (0, 0.25 and 2.0 ml/kg) of the Aloysia triphylla essential oil (EOAT) on silver catfish (Rhamdia quelen). Cortisol levels were lower in fish fed EOAT at 2.0 ml/kg diet, and lactate levels were lower in those fed at both doses. Glucose, alanine aminotransferase, aspartate aminotransferase and triglyceride levels did not vary between groups. The biomarkers of oxidative stress, thiobarbituric acid‐reactive substances, lipid hydroperoxide, superoxide dismutase, catalase and non‐protein thiols, were lower in the brain, liver and muscle of fish fed EOAT at 2.0 ml EO/kg diet. Glutathione‐S‐transferase, reduced glutathione, plasma Na+, Cl?, and K+, and gill Na+/K+‐ATPase and H+‐ATPase did not vary between groups. Taken together, our results clearly indicate that the addition of EOAT at 2.0 ml/kg diet improves oxidative status and lowers the stress response in silver catfish. 相似文献