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排序方式: 共有379条查询结果,搜索用时 15 毫秒
71.
Benjamin U. Akpoilih Bamidele O. Omitoyin Emmanuel K. Ajani 《Journal Of Applied Aquaculture》2017,29(2):126-151
The effect of microbial phytase on phosphorus utilization in juvenile Clarias gariepinus (initial fish body weight 11.55 ± 0.2 g) was tested on two different diets based on oil-extracted soya bean (Experiment 1) and roasted soya bean meal (Experiment 2) using a 5 × 5 experimental design for 84 days. The basal isonitrogenous and isocaloric diets for oil-extracted and roasted soya bean were formulated to replace fish meal at 25% (S1E), 50% (S2E), 75% (S3E), 100% (S4E); and 25% (S1), 50% (S2), 75% (S3), 100% (S4), respectively. Each treatment was replicated four times. Microbial phytase was supplemented in each replicate at 250 FTU/g (P1), 500 FTU/g (P2), 750 FTU/g (P3), and 1,000 FTU/g (P4). Basal controls, which included a fish meal-based diet (S0), were not supplemented with phytase (P0). The result in Experiment 1 showed that there was a significant increase in whole-body protein and reduction in fat with phytase compared to a diet without phytase (P < 0.05). Serum total protein declined significantly with phytase supplementation (P < 0.05). Serum phosphorus and glucose were higher with phytase supplementation compared to control (P < 0.05). Bone minerals declined significantly with increasing level of soya bean compared to fish meal diet (P < 0.05). In Experiment 2, serum phosphorus was improved with phytase compared to control with no phytase (P > 0.05). A significant reduction in whole-body protein and increase in fat was observed for fish fed phytase diets compared to diets with no phytase, regardless of soya bean level (P < 0.05); however, ash content was improved with phytase (250 FTU/g) compared to control (P < 0.05). Phytase supplementation improved bone phosphorus (250 FTU/g), calcium (250 FTU/g), magnesium (250–500 FTU/g), and zinc (250–1,000 FTU/g) compared to control (P < 0.05). In conclusion, the research has demonstrated that improved bone phosphorus (P) and growth could be achieved with the supplementation of dietary phytase. 相似文献
72.
Marília Hauser Carolina R.C. Doria Roberto V. Santos Aurea García‐Vasquez Marc Pouilly Christophe Pcheyran Emmanuel Ponzevera Gislene Torrente‐Vilara Sylvain Brail Jacques Panfili Audrey Darnaude Jean‐Franois Renno Carmen García‐Dvila Jesus Nuez Franck Ferraton Gladys Vargas Fabrice Duponchelle 《水产资源保护:海洋与淡水生态系统》2019,29(3):397-408
73.
Natalino da Costa Sousa Mrcia Valria Silva do Couto Higo Andrade Abe Peterson Emmanuel Guimares Paixo Carlos Alberto Martins Cordeiro Emilly Monteiro Lopes Jonathan Stuart Ready Gabriel Fernandes Alves Jesus Mauricio Latera Martins Jos Luiz Pereira Mourio Paulo Csar Falanghe Carneiro Alexandre Nizio Maria Rodrigo Yudi Fujimoto 《Aquaculture Research》2019,50(12):3720-3728
Intensive fish farming has resulted in an increased concern for disease outbreaks. Probiotic use is one of the strategies being developed to improve fish health and productivity. Measures of probiotic colonization, growth performance, haematological characteristics and parasite load were used to evaluate the effect of diets supplemented with Enterococcus faecium on growth and health of Arapaima gigas juveniles. A completely randomized design with four treatments (diet with E. faecium at 1 × 106 CFU/g and 1 × 108 CFU/g, control diet and diet with the culture medium MRS) and three replicates was used. Ninety‐six Arapaima juveniles were distributed in 12 cages fed with the specified diet for 68 days. Colonization of the intestinal tract by lactic acid bacteria reduced the total number of heterotrophic bacteria in fish fed with probiotics compared to controls. Fish fed a supplemented diet containing 1 × 108 CFU/g presented higher values of weight gain, survival and fish growth uniformity, and lower values of feed conversion ratio. The prevalence of Trichodina sp. could have affected the survival of fish in the control group. Reduction in parasite load and an increase in haematocrit, the number of erythrocytes, thrombocytes, neutrophils and monocytes were also observed in fish fed the diet containing 1 × 108 CFU/g. Enterococcus faecium presented a probiotic effect in A. gigas juveniles and can be recommended for use at a concentration of 1 × 108 CFU/g to modify the gut microbiota, improve growth performance and haematology and reduce parasitic load. 相似文献
74.
Marlies M. Gerdemann Andrea Machmüller Emmanuel Frossard Michael Kreuzer 《植物养料与土壤学杂志》1999,162(4):401-408
The objective of this study was to evaluate the extent to which altering pig nutrition for environmental reasons could affect the N fertilizing value of slurry. This was assessed by studying the nitrification of NH4-N and the N use efficiency of slurries obtained from growing pigs offered feeds either with commonly applied contents of crude protein (CP) and bacterially fermentable substrates (BFS) or reduced CP levels and/or elevated BFS levels. Soil/slurry mixtures were incubated for 16 weeks at 20°C using 0.2 g total slurry N addition per kg soil. In a 15 weeks lasting pot experiment with Lolium multiflorum, N derived from the same slurries was applied at two N doses with overall either 0.4 or 0.8 g total slurry N/kg soil. In the pot experiment the effect of slurry on plant growth and N uptake was compared with a mineral N fertilizer (NH4NO3) treatment and a non-fertilized control. Slurries obtained from pigs fed at reduced CP content had lower pH, total N content and proportion of NH4-N than slurries obtained from pigs fed at higher CP. Accordingly incubation of soil/slurry mixtures using slurries obtained from low CP feeds resulted in lower NO3-N concentration in the soil. Furthermore, a lower proportion of the added NH4-N was nitrified in treatments involving slurries derived from low CP feeds. Modifying the BFS content in feeds had minor effects both on slurry characteristics and on slurry NH4-N nitrification in soil. Although reduced CP and, to a lesser extent, elevated BFS altered the N release pattern to plants, slurry N use efficiency during the four cuts following the first fertilization ranged at a similar level of 32 to 33% for all types of slurry. This apparent use was significantly lower than that of the mineral N fertilizer which amounted to 72 to 75% of the added N. Nitrogen balance showed that less than 22% of the added mineral N fertilizer was lost from the soil/plant systems while from 32 to 47% of the N added with the slurries was lost independently of the type of slurry. So overall N utilization by crop and rate of slurry N recovery did not significantly differ which indicates that the investigated modifications of pig feeding appear to have no short term negative effect on the N fertilizing value of slurries. 相似文献
75.
76.
Ousmane Boukar Nouhoun Belko Siva Chamarthi Abou Togola Joseph Batieno Emmanuel Owusu Mohammed Haruna Sory Diallo Muhammed Lawan Umar Olusoji Olufajo Christian Fatokun 《Plant Breeding》2019,138(4):415-424
Cowpea, Vigna unguiculata (L.), is an important grain legume grown in the tropics where it constitutes a valuable source of protein in the diets of millions of people. Some abiotic and biotic stresses adversely affect its productivity. A review of the genetics, genomics and breeding of cowpea is presented in this article. Cowpea breeding programmes have studied intensively qualitative and quantitative genetics of the crop to better enhance its improvement. A number of initiatives including Tropical Legumes projects have contributed to the development of cowpea genomic resources. Recent progress in the development of consensus genetic map containing 37,372 SNPs mapped to 3,280 bins will strengthen cowpea trait discovery pipeline. Several informative markers associated with quantitative trait loci (QTL) related to desirable attributes of cowpea were generated. Cowpea genetic improvement activities aim at the development of drought tolerant, phosphorus use efficient, bacterial blight and virus resistant lines through exploiting available genetic resources as well as deployment of modern breeding tools that will enhance genetic gain when grown by sub‐Saharan Africa farmers. 相似文献
77.
78.
79.
Njoga Emmanuel Okechukwu Onunkwo Joseph I. Okoli Chinwe E. Ugwuoke Wilfred I. Nwanta John A. Chah Kennedy F. 《Tropical animal health and production》2018,50(4):897-902
Tropical Animal Health and Production - Imprudent administration of antimicrobial drugs in food-producing animals can facilitate the development and spread of antimicrobial-resistant organisms and... 相似文献
80.
Mathilde Bettembourg Audrey Dardou Alain Audebert Emilie Thomas Julien Frouin Emmanuel Guiderdoni Nourollah Ahmadi Christophe Perin Anne Dievart Brigitte Courtois 《Rice》2017,10(1):45