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91.
92.
Sara Bellezza Oddon Ilaria Biasato Arianna Imarisio Miha Pipan Dominik Dekleva Elena Colombino Maria Teresa Capucchio Marco Meneguz Stefania Bergagna Raffaella Barbero Marta Gariglio Sihem Dabbou Edoardo Fiorilla Laura Gasco Achille Schiavone 《Journal of animal physiology and animal nutrition》2021,105(Z1):10-18
The commercial broiler chicken strains are the result of successful selection programmes. Most of the problems related to welfare arise from the high growth rate and body weight. The use of environmental enrichments in intensive farming could have a positive effect on birds by increasing animal welfare. The aim of the study was to evaluate the effects of Hermetia illucens (HI) and Tenebrio molitor (TM) live larvae in the diets of broiler chickens on growth performance, carcass yield and health status. A total of 180 four-day-old male broiler chickens (Ross 308) were randomly allotted to 18 pens. Each pen was assigned to one of the three dietary treatments (6 replicates/treatment, 10 birds/replicate) as follows: (i) control diet (C): commercial feed (two feeding phases: starter [4–11 days] and grower [12–38 days]), (ii) HI: C + 5% of the expected daily feed intake (DFI) HI live larvae (calculated on dry matter [DM]) and (iii) TM: C + 5% of DFI TM live larvae (DM). At 39 days of age, birds were slaughtered. Growth performance parameters were overall not affected by dietary treatments, except for the grower phase feed conversion ratio (FCR) and the overall FCR being better in the TM broilers than the others (p < 0.01). No differences were observed for slaughtering performance and haematological and serum parameters, except for the spleen relative weight being higher (p < 0.01) in the birds administered with larvae when compared to the C group. Gut morphometric indexes and histopathological alterations were not influenced by insect larvae administration. In conclusion, the administration in limited quantities of HI and TM live larvae as environmental enrichment has no negative effects on broiler chicken growth performance and health status. A behavioural study could confirm that live insect larvae represent a novel natural environmental enrichment in broiler farming. 相似文献
93.
VP1蛋白是口蹄疫病毒(FMDV)的主要结构蛋白,可诱导机体产生中和抗体以及激发保护性免疫应答。为探究VP1基因密码子偏好性,筛选出其最佳体外表达系统,使用Visual Gene Developer、CodonW、GraphPad Prism等软件,对VP1基因进行密码子偏好性分析,同时将VP1基因密码子使用频率与大肠杆菌、毕赤酵母、昆虫杆状病毒和哺乳动物细胞表达系统作了比较。结果显示,VP1基因的CAI为0.21,ENC为55.43,GC3S为65.26%,表明该基因密码子使用偏好较弱并且密码子偏好以G/C碱基结尾。结合VP1基因与各表达系统密码子使用频率比值,发现其与昆虫杆状病毒表达系统频率比值差异最小且CAI最大,因此推断昆虫杆状病毒表达系统是FMDV VP1基因最适体外表达系统。本研究为FMDV亚单位疫苗研制等提供了技术基础。 相似文献
94.
I. Biasato M. De Marco L. Rotolo M. Renna C. Lussiana S. Dabbou M. T. Capucchio E. Biasibetti P. Costa F. Gai L. Pozzo D. Dezzutto S. Bergagna S. Martínez M. Tarantola L. Gasco A. Schiavone 《Journal of animal physiology and animal nutrition》2016,100(6):1104-1112
Insects are currently being considered as a novel protein source for animal feeds, because they contain a large amount of protein. The larvae of Tenebrio molitor (TM) have been shown to be an acceptable protein source for broiler chickens in terms of growth performance, but till now, no data on histological or intestinal morphometric features have been reported. This study has had the aim of evaluating the effects of dietary TM inclusion on the performance, welfare, intestinal morphology and histological features of free‐range chickens. A total of 140 medium‐growing hybrid female chickens were free‐range reared and randomly allotted to two dietary treatments: (i) a control group and (ii) a TM group, in which TM meal was included at 75 g/kg. Each group consisted of five pens as replicates, with 14 chicks per pen. Growth performance, haematological and serum parameters and welfare indicators were evaluated, and the animals were slaughtered at the age of 97 days. Two birds per pen (10 birds/treatment) were submitted to histological (liver, spleen, thymus, bursa of Fabricius, kidney, heart, glandular stomach and gut) and morphometric (duodenum, jejunum and ileum) investigations. The inclusion of TM did not affect the growth performance, haematological or serum parameters. The morphometric and histological features were not significantly affected either, thus suggesting no influence on nutrient metabolization, performance or animal health. Glandular stomach alterations (chronic flogosis with epithelial squamous metaplasia) were considered paraphysiological in relation to free‐range farming. The observed chronic intestinal flogosis, with concomitant activation of the lymphoid tissue, was probably due to previous parasitic infections, which are very frequently detected in free‐range chickens. In conclusion, the findings of this study show that yellow mealworm inclusion does not affect the welfare, productive performances or morphological features of free‐range chickens, thus confirming that TM can be used safely in poultry diets. 相似文献
95.
小火蚁是中国大陆新发现的重要外来入侵害虫, 目前对该虫的传入来源和在我国的适生区范围尚不明确?为明确我国小火蚁适生区范围, 有效防控该虫在我国的扩散和蔓延, 本研究通过该虫全球已有的分布数据, 采用最大熵模型对其适生区进行了预测?研究表明, 最大熵模型预测小火蚁适生区精度较高?预测结果显示, 我国小火蚁的潜在适生区主要分布于南方, 其中, 高适生区分布在台湾?海南?云南南部边境?广西西南局部?福建西南部?广东南部及其沿海地区?预测结果与该物种现有地理范围的生态条件一致?年降水量对小火蚁的适生性影响最大, 理论年降水量为2 040 mm时小火蚁分布的概率最高?随着全球气候变暖, 未来我国小火蚁的适生区有向北扩大的趋势, 但主要适生区还是以南方为主? 相似文献
96.
97.
Nickolas G. Kavallieratos Maria C. Boukouvala Artemis Phoebe A. Pappa Angelo Canale Giovanni Benelli 《Pest management science》2023,79(12):5230-5236
BACKGROUND
Sublethal effects of insecticides may negatively affect several biological and behavioral traits of insects. The lethal effects of pirimiphos-methyl and chlorfenapyr have been previously showed on Trogoderma granarium, but little knowledge is available about their sublethal effects at low concentrations on both sexes. Herein, the sublethal effects of pirimiphos-methyl and chlorfenapyr on the mobility of T. granarium males and females were investigated.RESULTS
Lethal concentration (LC) values of pirimiphos-methyl and chlorfenapyr were lower for T. granarium females than males. LC values on males were LC10 = 0.000788 and 0.00139 mg active ingredient (a.i.) cm−2, LC30 = 0.00350 and 0.00535 mg a.i. cm−2, and LC50 = 0.00986 and 0.0136 mg a.i. cm−2 for pirimiphos-methyl and chlorfenapyr respectively. LC on females were LC10 = 0.000704 and 0.00110 mg a.i. cm−2, LC30 = 0.00323 and 0.00428 mg a.i. cm−2, and LC50 = 0.00925 and 0.0110 mg a.i. cm−2 for pirimiphos-methyl and chlorfenapyr respectively. The walking duration of beetles exposed to LC30 of pirimiphos-methyl was significantly lower than the individuals exposed to LC10 and LC30 of both insecticides and control ones. Pirimiphos-methyl LC30-exposed males remained more time on their back (101.7 s) than females (46.9 s), while the latter stayed immobile longer than males (381.7 s versus 371.9 s). The highest speed was recorded for control beetles (14.17 mm s−1 females vs. 12.44 mm s−1 males), while the lowest speed was observed in pirimiphos-methyl LC30-treated males (8.36 mm s−1) and females (9.66 mm s−1).CONCLUSIONS
Overall, males and females exposed to low concentrations of pirimiphos-methyl and chlorfenapyr showed reduced motility. This knowledge can be exploited further to unlock behavioral effects of insecticides for effective pest management programs in warehouses. © 2023 Society of Chemical Industry. 相似文献98.
99.
为筛选出对葡萄害虫诱集效果好的粘虫板,选用黄色、蓝色、白色、紫色、绿色、红色、黑色和荧光色8种颜色的粘虫板对葡萄园内昆虫进行诱集试验。结果表明,共诱到昆虫7目18科22种,主要害虫有蓟马、蚜虫和叶蝉,其中蓟马数量占到昆虫总量的88.96%,天敌昆虫主要有寄生蜂、捕食性瓢虫、食蚜蝇和东亚小花蝽。紫板、蓝板和白板对蓟马的诱集效果强,黄板、荧光板和绿板次之,红板和黑板效果差;黄板对蚜虫诱集效果强,绿板和荧光板次之,黄板与其他色板之间差异显著;黄板、荧光板和绿板对叶蝉的诱集效果好,3种色板与蓝板之间差异不显著、与其他色板差异显著。白板、蓝板和黄板诱集到的天敌数量最多,占所有颜色粘虫板诱集天敌总量的69%左右。试验期间诱集到的昆虫益害比为0.036,各色板的益害比依次为黑色>荧光色>绿色>红色>黄色>白色>蓝色>紫色,其中紫板的益害比最低,仅为0.011。结合各色板的诱虫效果和益害比进行综合分析,建议选用紫板对蓟马进行诱杀,适时适量选择性使用黄板对蚜虫、叶蝉等进行诱杀。 相似文献
100.
在大数据时代,海量的数据资源是推动经济发展和社会进步的基石,丰富、透明、完善的农业大数据资源是加快农业信息化建设步伐的前提,先进、有序、完备的农业病虫害监测预警体系是服务绿色农业发展的支撑。该研究试图在研究国内外农业病虫害监测预警体系的基础上,在农业专家的指导下,进行大数据时代农业病虫害监测预警体系构建。山东农业病虫害监测预警体系的建设应主动适应大数据时代的发展需求,分步构建病虫害监测预警体系,分层划分病虫害数据中心工作,合理布局病虫害数据采集站点,科学制定病虫害监测预警任务,共建共享病虫害监测数据信息,有效加强病虫害联合监测预警,努力研发病虫害智能识别终端,为发展现代高效农业提供坚实的保障。 相似文献