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    Special Focus: Development and Application of Plant Transformation Techniques
    Development and application of plant transformation techniques
    YE Xing-guo
    2015, 14(3): 411-413.  DOI: 10.1016/S2095-3119(14)60945-X
    Abstract ( )   PDF in ScienceDirect  
    Overexpression of a modified AM79 aroA gene in transgenic maize confers high tolerance to glyphosate
    REN Zhen-jing, CAO Gao-yi, ZHANG Yu-wen, LIU Yan, LIU Yun-jun
    2015, 14(3): 414-422.  DOI: 10.1016/S2095-3119(14)60920-5
    Abstract ( )   PDF in ScienceDirect  
    It has previously been shown that a bacterial 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) encoding gene AM79 aroA can be a candidate gene to develop glyphosate-tolerant transgenic crops (Cao et al. 2012). In this study, AM79 aroA was redesigned using the plant biased codons and eliminating the motifs which would lead to the instability of mRNA, to create a synthetic gene that would be expressed highly in plant cells. The redesigned and artificially synthesized gene, named as mAM79, was cloned into plant expression vector pM3301UbiSpAM79, where mAM79 is fused with signal peptide sequence of pea rib-1,5-bisphospate carboxylase (rbcS) small subunit and controlled by ubiquitin promoter. The plasmid was transformed into maize (Zea mays) immature embryos using Agrobacterium-mediated transformation method. Total 74 regenerated plants were obtained and PCR analysis showed that these transgenic plants had the integration of mAM79. Southern blot analysis was performed on the genomic DNA from four transgenic lines, and the result showed that one or two copies of mAM79 were integrated into maize genome. RT-PCR analysis result indicated that mAM79 was highly transcribed in transgenic maize plants. When sprayed with glyphosate, transgenic maize line AM85 and AM72 could tolerate 4-fold of commercial usage of glyphosate; however, all the non-transgenic maize plants were killed by glyphosate. The results in this study confirmed that mAM79 could be used to develop glyphosate-tolerant maize, and the obtained transgenic maize lines could be used for the breeding of glyphosate-tolerant maize.
    Development of lepidopteran pest-resistant transgenic japonica rice harboring a synthetic cry2A* gene
    JIN Yong-mei, MA Rui, YU Zhi-jing, WANG Ling, JIANG Wen-zhu, LIN Xiu-feng
    2015, 14(3): 423-429.  DOI: 10.1016/S2095-3119(14)60897-2
    Abstract ( )   PDF in ScienceDirect  
    A synthetic cry2A* gene encoding Bacillus thuringiensis (Bt) δ-endotoxin that resistance to lepidopteran pest was transformed into japonica rice variety Jijing 88, which is the most widely cultivated variety in Jilin Province, Northeast China, by Agrobacterium-mediated transformation. A total of 106 independent transformants overexpressing cry2A* gene driven by ubiquitin (Ubi) promoter was produced. Three single-copy homozygous transgenic lines were finally selected based on the results of PCR analysis, segregation ratio of Basta resistance, and Southern hybridization analyses. RT-PCR and enzyme linked immune sorbent assay (ELISA) revealed that cry2A* transcripts and protein were highly expressed in these lines. The high level of Cry2A* protein expression resulted in high resistance to rice striped stem borer as evidenced by insect feeding bioassays. Our results demonstrate that cry2A* transgenic japonica rice confers resistance to the rice striped stem borer in the laboratory conditions.
    Enhanced resistance to Botrytis cinerea and Rhizoctonia solani in transgenic broccoli with a Trichoderma viride endochitinase gene
    YU Ya, ZHANG Lei, LIAN Wei-ran, XU Feng-feng, LI Shuang-tao, XIANG Juan, ZHANG Guo-zhen, HU Zan-min, ZHAO Bing, REN Shu-xin, GUO Yang-dong
    2015, 14(3): 430-437.  DOI: 10.1016/S2095-3119(14)60919-9
    Abstract ( )   PDF in ScienceDirect  
    A endochitinase gene (Tch) from the fungus Trichoderma viride was introduced into broccoli (Brassica oleracea var. italica) by Agrobacterium-mediated transformation. Sixty-eight putative transformants were obtained and the presence of the Tch gene was confirmed by both PCR and Southern blot analysis. RT-PCR analysis showed an accumulation of the transcript encoding the endochitinase protein in the transgenic plants. Using real-time quantitative PCR, the expression profiling of endochitinase gene was analyzed. Primary transformants and selfed progeny were examined for expression of the endochitinase using a fluorometric assay and for their resistance to the pathogenic fungi Botrytis cinerea and Rhizoctonia solani. The endochitinase activities in T0 in vitro plants, T0 mature plants and T1 mature plants were correlated with leaf lesions, and the transgenic line T618 had high endochitinse activities of 102.68, 114.53 and 120.27 nmol L–1 MU min–1 mg–1 protein in the three kinds of plants, respectively. The endochitinase activity showed a positive correlation with the resistance to the pathogens. Most transgenic T0 broccoli had increased resistance to the pathogens of B. cinerea and R. solani in leaf assays and this resistance was confirmed to be inheritable. These findings suggested that expression of the Tch gene from T. viride could enhance resistance to pathogenic fungi in Brassica species.
    Current status and trends of wheat genetic transformation studies in China
    HE Yi, WANG Qiong, ZENG Jian, SUN Tao, YANG Guang-xiao, HE Guang-yuan
    2015, 14(3): 438-452.  DOI: 10.1016/S2095-3119(14)60934-5
    Abstract ( )   PDF in ScienceDirect  
    More than 20 years have passed since the first report on successful genetic transformation of wheat. With the establishment and improvement of transformation platform, great progresses have been made on wheat genetic transformation both on its fundamental and applied studies in China, especially driven by the National Major Project for Transgenic Organism Breeding, China, initiated in 2008. In this review, wheat genetic transformation platform improvement and transgenic research progresses including new techniques applied and functional studies of wheat quality, yield and stress tolerant related genes and biosafety assessment are summarized. The existing problems and the trends in wheat transformation with traditional methods combined with genomic studies and genome editing technology are also discussed.
    Constructing the barley model for genetic transformation in Triticeae
    Lü Bo, WU Jia-jie, FU Dao-lin
    2015, 14(3): 453-468.  DOI: 10.1016/S2095-3119(14)60935-7
    Abstract ( )   PDF in ScienceDirect  
    Barley (Hordeum vulgare L.) is one of the oldest domesticated crops, showing dramatic adaptation to various climate and environmental conditions. As a major cereal crop, barley ranks the 4th after wheat, maize and rice in terms of planting area and production all over the world. Due to its diploid nature, the cultivated barley is considered as an ideal model to study the polyploid wheat and other Triticeae species. Here, we reviewed the development, optimization, and application of transgenic approaches in barley. The most efficient and robust genetic transformation has been built on the Agrobacterium-mediated transfer in conjunction with the immature embryo-based regeneration. We then discussed future considerations of using more practical technologies in barley transformation, such as the T-DNA/transposon tagging and the genome editing. As a cereal crop amenable to genetic transformation, barley will serve as the most valuable carrier for global functional genomics in Triticeae and is becoming the most practical model for generating value-added products.
    Current status of genetic transformation technology developed in cucumber (Cucumis sativus L.)
    WANG Shun-li, Seong Sub Ku, YE Xing-guo, HE Cong-fen, Suk Yoon Kwon, Pil Son Choi
    2015, 14(3): 469-482.  DOI: 10.1016/S2095-3119(14)60899-6
    Abstract ( )   PDF in ScienceDirect  
    Genetic transformation is an important technique for functional genomics study and genetic improvement of plants. Until now, Agrobacterium-mediated transformation methods using cotyledon as explants has been the major approach for cucumber, and its frequency has been up to 23%. For example, significantly enhancement of the transformation efficiency of this plant species was achieved from the cotyledon explants of the cultivar Poinsett 76 infected by Agrobacterium strains EHA105 with efficient positive selection system in lots of experiments. This review is to summarize some key factors influencing cucumber regeneration and genetic transformation, including target genes, selection systems and the ways of transgene introduction, and then to put forward some strategies for the increasing of cucumber transformation efficiency. In the future, it is high possible for cucumber to be potential bioreactor to produce vaccine and biomaterials for human beings.
    Plant regeneration and genetic transformation in switchgrass-A review
    Paul Merrick, Shuizhang Fei
    2015, 14(3): 483-493.  DOI: 10.1016/S2095-3119(14)60921-7
    Abstract ( )   PDF in ScienceDirect  
    Switchgrass is native to the tallgrass prairie of North America. It is self-incompatible and has varied ploidy levels from diploid (2x) to dodecaploid (12x) with tetraploid and octoploid being the most common. The high yielding potential and the ability to grow well in marginal lands make switchgrass an ideal species as a dedicated biomass producer for lignocellulosic ethanol production. Genetic transformation is an important tool for studying gene function and for germplasm improvement in switchgrass, the genome of which has been sequenced recently. This paper intends to provide a comprehensive review on plant regeneration and genetic transformation in switchgrass. We first reviewed the effect of explants, basal medium and plant growth regulators on plant regeneration in switchgrass, which is a prerequisite for genetic transformation. We then reviewed the progresses on genetic transformation with either the biolistic or Agrobacterium-mediated method in switchgrass, and discussed various techniques employed to improve the transformation efficiency. Finally we reviewed the recent progresses on the use of genetic transformation in improving biomass quality such as the reduction of lignin, and in increasing biomass yield in switchgrass. We also provided a future perspective on the use of new genome editing technologies in switchgrass and its potential impact on regulatory processes.
    Special Focus: Direct-Fed Microbial - Animal Nutrition and Reproduction Responses
    Direct-fed microbial: Animal nutrition and reproduction responses
    Abdelfattah Z M Salem, Nicolas DiLorenzo
    2015, 14(3): 494-496.  DOI: 10.1016/S2095-3119(14)60956-4
    Abstract ( )   PDF in ScienceDirect  
    Effect of a bacterial inoculum and additive on dry matter in situ degradability of sugarcane silage
    José A Reyes-Gutiérrez, Oziel D Monta?ez-Valdez, Ramón Rodríguez-Macias, Mario Ruíz-López, Eduardo Salcedo-Pérez, Cándido E Guerra-Medina
    2015, 14(3): 497-502.  DOI: 10.1016/S2095-3119(14)60826-1
    Abstract ( )   PDF in ScienceDirect  
    The objective of this study was to evaluate the effect of adding a bacterial inoculum and a handmade additive to sugarcane silage (SCS) on the in situ digestibility of dry matter (DM). The treatments were: T1) sugarcane silage (SCS) and T2) sugarcane silage with 1% inoculum and 1% additive (SCS+). The bacterial inoculum consisted of 10.0% molasses, 1.0% yogurt, 5.0% chicken manure, 0.5% urea, and 83.0% water, and the additive was formulated with 1.0% urea, 0.1% ammonium sulfate, and 0.25% phosphorus. In situ dry matter digestibility (DMD) was determined using the nylon bag technique with four cows equipped with ruminal fistulas. Cows were fed with ensiled sugarcane supplemented with 1 kg of commercial concentrate. 5 g of ground sample for each sugarcane treatment were weighted in nylon bags and incubated for 4, 8, 12, 24, 48, and 72 h in a completely randomized design with six replicates. The DMD (%) was higher (P<0.05) for SCS+ for all incubation times when compared with SCS. There were no differences in ruminal pH between the treatments for all the incubation times. The data suggested that the sugarcane silage with bacterial inoculum and additive could be an alternative for providing forage for ruminants during the season of low growth and quality grass.
    The effects of fermentation and adsorption using lactic acid bacteria culture broth on the feed quality of rice straw
    LIU Jing-jing, LIU Xiao-ping, REN Ji-wei, ZHAO Hong-yan, YUAN Xu-feng, WANG Xiao-fen, Abdelfattah Z M Salem, CUI Zong-jun
    2015, 14(3): 503-513.  DOI: 10.1016/S2095-3119(14)60831-5
    Abstract ( )   PDF in ScienceDirect  
    To improve the nutritional value and the palatability of air-dried rice straw, culture broth of the lactic acid bacteria community SFC-2 was used to examine the effects of two different treatments, fermentation and adsorption. Air-dried and chopped rice straw was treated with either fermentation for 30 d after adding 1.5 L nutrient solution (50 mL inocula L–1, 1.2×1012 CFU mL–1 inocula) kg–1 straw dry matter, or spraying a large amount of culture broth (1.5 L kg–1 straw dry matter, 1.5×1011 CFU mL–1 culture broth) on the straw and allowing it to adsorb for 30 min. The feed quality and aerobic stability of the resulting forage were examined. Both treatments improved the feed quality of rice straw, and adsorption was better than fermentation for preserving nutrients and improving digestibility, as evidenced by higher dry matter (DM) and crude protein (CP) concentrations, lower neutral detergent fiber (NDF), acid detergent fiber (ADF) and NH3-N concentrations, as well as higher lactic acid production and in vitro digestibility of DM (IVDMD). The aerobic stability of the adsorbed straw and the fermented straw was 392 and 480 h, respectively. After being exposed to air, chemical components and microbial community of the fermented straw were more stable than the adsorbed straw.
    Feeding of yeast (Candida spp.) improves in vitro ruminal fermentation of fibrous substrates
    Yo , ra Marrero, Yamicela Castillo, Oscar Ruiz, Eduviges Burrola, Claudio Angulo
    2015, 14(3): 514-519.  DOI: 10.1016/S2095-3119(14)60830-3
    Abstract ( )   PDF in ScienceDirect  
    In vitro gas production technique (IVGPT) was used with the objective of determining the inclusion effect of live cells of two strains of Candida yeast on in vitro ruminal fermentation of two fibrous substrates. In order to achieve this, two experiments were performed: A) using oat straw (Avena sativa) as substrate; B) using alfalfa hay (Medicabo sativa) as substrate, comparing the effect of two different strains of Candida genre, both isolated from the rumen, on the mentioned substrates. Levica 25 (Candida tropicalis) yeast belongs to the culture collection of the Institute of Animal Science, Cuba, and Levazoot 15 (Candida norvegensis) yeast is part of the collection of the Faculty of Zootechnology and Ecology of the Autonomous University of Chihuahua, Mexico. Both strains demonstrated their potential in activating the ruminal fermentation. They stimulated (P<0.0001) the ruminal fermentation of the substrates under study. However, the Levazoot strain stimulated the dry matter (DM) fermentation of alfalfa in 21.43%, more than Levica 25. It is concluded that there is an influence of yeast strain and diet on the rumen environment and, therefore, it is important to select the appropriate strain in every production condition.
    The effect of Saccharomyces cerevisiae on digestion and mortality in the volcano rabbit (Romerolagus diazi)
    Rogelio Campos-Morales, Germán D Mendoza, Javier Ojeda, Fern , o X Plata, José A Martínez
    2015, 14(3): 520-525.  DOI: 10.1016/S2095-3119(14)60828-5
    Abstract ( )   PDF in ScienceDirect  
    An experiment was conducted to evaluate whether supplementation with a probiotic could enhance digestion and reduce mortality in the volcano rabbit in captivity. Two enclosures at Chapultepec Zoo, Mexico (114 individuals) were used in a crossover design (two periods of 60 days) with the following treatments: control group and supplementation with Saccharomyces cerevisiae (2×108 CFU/exhibit/day). Supplementation with the probiotic negatively affected (P<0.01) the digestibility of dry matter, organic matter, neutral detergent fiber (NDF) and energy. Mortality increased (P<0.04) following supplementation with the probiotic (4.26% vs. 8.89%), primarily in the juvenile rabbits. The results indicate that yeast supplementation in the volcano rabbit negatively affects digestion and mortality in captivity.
    Section 2: Fungi, enzymes and new developments in direct-fed microbials
    Direct-fed microbes: A tool for improving the utilization of low quality roughages in ruminants
    Mona M Y Elghandour, Abdelfattah Z M Salem, Jose S Martínez Castaneda, Luis M Camacho, Ahmed E Kholif, Juan C Vázquez Chagoyán
    2015, 14(3): 526-533.  DOI: 10.1016/S2095-3119(14)60834-0
    Abstract ( )   PDF in ScienceDirect  
    For many years, ruminant nutritionists and microbiologists have been interested in manipulating the microbial ecosystem of the rumen to improve production efficiency of different ruminant species. Removal and restriction of antibiotics subtherapeutic uses from ruminant diets has amplified interest in improving nutrient utilization and animal performance and search for more safe alternatives. Some bacterial and fungal microorganisms as a direct-fed microbial (DFM) can be the most suitable solutions. Microorganisms that are commonly used in DFM for ruminants may be classified mainly as lactic acid producing bacteria (LAB), lactic acid utilizing bacteria (LUB), or other microorganism’s species like Lactobacillus, Bifidobacterium, Enterococcus, Streptococcus, Bacillus, Propionibacterium, Megasphaera elsdenii and Prevotellabryantii, in addition to some fungal species of yeast such as Saccharomyces and Aspergillus. A definitive mode of action for bacterial or fungal DFM has not been established; although a variety of mechanisms have been suggested. Bacterial DFM potentially moderate rumen conditions, and improve weight gain and feed efficiency. Fungal DFM may reduce harmful oxygen from the rumen, prevent excess lactate production, increase feed digestibility, and alter rumen fermentation patterns. DFM may also compete with and inhibit the growth of pathogens, immune system modulation, and modulate microbial balance in the gastrointestinal tract. Improved dry matter intake, milk yield, fat corrected milk yield and milk fat content were obtained with DFM administration. However, the response to DFM is not constant; depending on dosages, feeding times and frequencies, and strains of DFM. Nonetheless, recent studies have supported the positive effects of DFM on ruminant performance.
    Biological treatments as a mean to improve feed utilization in agriculture animals-An overview
    Nahla A Abdel-Aziz, Abdelfattah Z M Salem, Mounir M El-Adawy, Luis M Camacho, Ahmed EKholif, Mona M Y Elghandour, Borhami E Borhami
    2015, 14(3): 534-543.  DOI: 10.1016/S2095-3119(14)60829-7
    Abstract ( )   PDF in ScienceDirect  
    As a result of agriculture practices, million tons of agriculture are produced as a secondary or by-products; however, with low nutritive values. Many methods are applied to improve the nutritive value and increase its utilization in ruminant’s nutrition. The biological treatments are the most common with more safe-treated products. In most cases, the biological treatments are paralleled with decreased crude fiber and fiber fractions content with increased crude protein content. Direct-fed microbial and exogenous enzymes to animal are other ways of biological methods for improving nutritive value of feeds. Here in this review, we will try to cover the biological treatments of by-products from different sides view with different types of animals and different animal end-products.
    Effects of exogenous enzymes, Lactobacillus acidophilus or their combination on feed performance response and carcass characteristics of rabbits fed sugarcane bagasse
    Nahla A Abdel-Aziz, Mounir El-Adawy, Maria A Mariezcurrena-Berasain, Abdelfattah Z M Salem, Jaime Olivares-Pérez, Ahmed E Kholif, Borhami E Borhami
    2015, 14(3): 544-549.  DOI: 10.1016/S2095-3119(14)60827-3
    Abstract ( )   PDF in ScienceDirect  
    The aim of this study was to evaluate the effect of Lactobacillus acidophilus (LAC), exogenous enzymes of ZAD® (exogenous enzyme preparation) or their combination on feed conversion, and dressing of rabbits fed different treatments of sugarcane bagasse (SCB). Five rations were allotted randomly to five groups of New-Zealand White (NZW) rabbits (n=10) with initial live body weight of (838±42.4) g and 5 weeks of age. Rabbits were fed on diets with different sources of fiber as follows, (i) a control diet composed of 100% berseem hay and 0% SCB, (ii) 50% berseem hay and 50% untreated SCB (USCB), (iii) 50% berseem hay and 50% SCB treated with L. acidophilus (LAC), (iv) 50% berseem hay and 50% SCB treated with ZAD® (ZAD), and (v) 50% berseem hay and 50% SCB treated with a combination of LAC+ZAD® (LZ). Treatments of SCB with L. acidophilus, ZAD® and LAC+ZAD® had the highest feed conversion ratio than both USCB and control. The dressing percentage of rabbits that fed the LAC and LZ diets was higher (P<0.05) compared with that in the other groups. Performance index (PI) for LAC group was improved (P<0.05) compared to that for the other groups; however, PI for USCB group was the lowest (P<0.05). It could be concluded that treating SCB with L. acidophilus, exogenous enzymes of ZAD® or their combination improved feed conversion and performance with more positive effects with L. acidophilus than the other treatments.
    Role of live microbial feed supplements with reference to anaerobic fungi in ruminant productivity: A review
    Anil K Puniya, Abdelfattah Z M Salem, Sanjay Kumar, Sumit S Dagar, Gareth W Griffith, Monica Puniya, Sreenivas R Ravella, Nikhil Kumar, Tejpal Dhewa, Ravinder Kumar
    2015, 14(3): 550-560.  DOI: 10.1016/S2095-3119(14)60837-6
    Abstract ( )   PDF in ScienceDirect  
    To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials (DFM) for improved animal performance in terms of growth or productivity. This becomes all the more essential in a situation, where a number of the residues of antibiotics and/or other growth stimulants reach in milk and meat with a number of associated potential risks for the consumers. Hence, in the absence of growth stimulants, a positive manipulation of the rumen microbial ecosystem to enhance the feedstuff utilization for improved production efficiency by ruminants has become of much interest to the researchers and entrepreneurs. A few genera of live microbes (i.e., bacteria, fungi and yeasts in different types of formulations from paste to powder) are infrequently used as DFM for the domestic ruminants. These DFM products are live microbial feed supplements containing naturally occurring microbes in the rumen. Among different DFM possibilities, anaerobic rumen fungi (ARF) based additives have been found to improve ruminant productivity consistently during feeding trials. Administration of ARF during the few trials conducted, led to the increased weight gain, milk production, and total tract digestibility of feed components in ruminants. Anaerobic fungi in the rumen display very strong cell-wall degrading cellulolytic and xylanolytic activities through rhizoid development, resulting in the physical disruption of feed structure paving the way for bacterial action. Significant improvements in the fiber digestibility were found to coincide with increases in ARF in the rumen indicating their role. Most of the researches based on DFM have indicated a positive response in nutrient digestion and methane reducing potential during in vivo and/or in vitro supplementation of ARF as DFM. Therefore, DFM especially ARF will gain popularity but it is necessary that all the strains are thoroughly studied for their beneficial properties to have a confirmed ‘generally regarded as safe’ status for ruminants.
    Prospective use of bacteriocinogenic Pediococcus pentosaceus as direct-fed microbial having methane reducing potential
    Sanjay Kumar, Sumit S Dagar, Seyed H Ebrahimi, Ravinder K Malik, Ramesh C Upadhyay, AnilK Puniya
    2015, 14(3): 561-566.  DOI: 10.1016/S2095-3119(14)60832-7
    Abstract ( )   PDF in ScienceDirect  
    Direct-fed microbials (DFM), generally regarded as safe status, are successfully used in improving rumen ecology, gastro-intestinal health, feed efficiency, milk production and growth rate in ruminants. On the other hand, methanogenesis in rumen, which accounts for a significant loss of ruminant energy and increased greenhouse gas in environment, is of great concern, therefore, use of DFM for improving productivity without compromising the animal health and ecological sustainability is encouraged. The present study was conducted to investigate the methane reducing potential of bacteriocinogenic strain Pediococcus pentosaceus-34. Since, the culture showed no hemolysis on blood agar and DNase activity, hence, it was considered to be avirulent in nature, a prerequisite for any DFM. The culture also showed tolerance to pH 5.0 for 24 h with 0.5% organic acid mixture, whereas when given a shock for 2 h at different pH and organic acids concentrations, it showed growth at pH 3.0 and 4.0 with 0.1 and 1.0% organic acids, respectively, as having good animal probiotics attributes. The total gas production was significantly (P<0.05) higher in live pedicoccal culture (LPC) and dead pedicoccal culture (DPC) both with wheat straw, when compared to the control. In sugarcane bagasse, gas production was significantly lower (P<0.05) with LPC compared to the control and DPC both. Methane was reduced by the inclusion of LPC in sugarcane bagasse (0.07 mL CH4 mg–1 dry matter digestibility) with no effect on other rumen fermentation parameters. However, with wheat straw and LPC total gas, in vitro dry matter digestibility, total volatile fatty acids increased significantly but no reduction in methane production was observed in comparison to the control. Therefore, further research is warranted in this direction, if the bacteriocinogenic strains can be used as DFM for ruminants to improve the ruminant productivity.
    Effects of organic chromium supplementation to finishing lambs diet on growth performance, carcass characteristics and meat quality
    Laura Moreno-Camarena, Ignacio Domínguez-Vara, José Bórquez-Gastelum, Juan Sánchez-Torres, Juan Pinos-Rodríguez, Antonia Mariezcurrena-Berasain, Ernesto Morales-Almaráz, Abdelfattah Z M Salem
    2015, 14(3): 567-574.  DOI: 10.1016/S2095-3119(14)60835-2
    Abstract ( )   PDF in ScienceDirect  
    The objective of this study was to evaluate supplemental organic chromium (Cr) to finishing lambs on growth performance, carcass characteristics, and meat quality. Eighteen Suffolk lambs (age (4.5±0.2) mon; (25.8±3.6) kg body weight (BW)) were randomly assigned to three levels of supplemental organic Cr (0.0, 0.2 and 0.4 mg kg–1 dry matter (DM)) in a complete random design. Growth performance was evaluated for 70 d, and then lambs were slaughtered to study carcass characteristics and chemical composition of meat. Orthogonal contrasts were performed (contrast one-average level 0.2 ppm Cr vs. average level 0.4 ppm Cr; contrast two-level 0 vs. average levels (0.2+0.4) ppm Cr). Orthogonal polynomials were used to estimate the linear and quadratic effects of Cr concentrations. Growth and carcass performance were not affected by supplemental organic Cr. Muscle conformation and leg perimeter linearly increased (P<0.05) as organic Cr level increased in the diet. Kidney fat decreased linearly (P<0.05) as supplemental Cr increased. In Longissimus dorsi (LD), the ash content decreased linearly, and shear force (kg cm–2) increased (P<0.05) as organic Cr level increased in the diet. It is concluded that organic Cr did not affect growth performance, but it improved positively the muscle conformation, reduced kidney fat, whereas in LD there was an increment in shear force in finishing carcass lambs.
    Effects of feeding yeast (Saccharomyces cerevisiae), organic selenium and chromium mixed on growth performance and carcass traits of hair lambs
    Pedro A Hernández-García, Alejandro Lara-Bueno, Germán D Mendoza-Martínez, José R Bárcena-Gama, Fernando X Plata-Pérez, Rufino López-Ordaz, José A Martínez-García
    2015, 14(3): 575-582.  DOI: 10.1016/S2095-3119(14)60833-9
    Abstract ( )   PDF in ScienceDirect  
    Yeasts and organic minerals are used in diets to improve health, productive performance and some carcass characteristics of ruminants and non-ruminants. Thirty-two lambs (Pelibuey×Katahdin; BW=(30.55±1.67) kg; n=8) were used in a 56-d feeding experiment to study the effects of different levels of live yeast (Saccharomyces cerevisiae; yeast), selenium (Se) and chromium (Cr) mixed (Se-Cr), and a mixture of yeast-Se-Cr on growth performance and carcass traits. Animals were stratified by body weight (BW) and randomly assigned to one of four treatments: 1) control group (0.0 g kg–1 yeast); 2) yeast (1.50 g kg–1 dry matter intake (DMI) d–1); 3) Se-Cr premix (1.5 mg kg–1 DMI d–1 for each mineral); and 4) yeast-Se-Cr mixture. There were no treatment effects on final BW; whereas lambs fed Se-Cr or yeast-Se-Cr had higher (P<0.05) DMI than animals supplemented with only yeast. Average daily gain (ADG), gain:feed ratio, chop area, dorsal fat and carcass yield were similar (P>0.05) among treatment groups. In conclusion, supplementation with yeast, Se-Cr mixed or yeast-Se-Cr did not improve ADG, final BW, back fat content and carcass yield of growing of Pelibuey×Katahdin lambs. Supplementation with Se-Cr and yeast-Se-Cr increased DMI, and approximately 250 g ADG animal–1 d–1 was produced with no negative effects on growth and health of the animals.
    Antimicrobial ability and growth promoting effects of feed supplemented with probiotic bacterium isolated from gut microflora of Cirrhinus mrigala
    Anita Bhatnagar, Ritu Lamba
    2015, 14(3): 583-592.  DOI: 10.1016/S2095-3119(14)60836-4
    Abstract ( )   PDF in ScienceDirect  
    The present studies were conducted to isolate, select, identify and characterize gut bacteria as antimicrobial and growth promoting agent for the feed of economically important fish Cirrhinus mrigala. Intestinal microflora were isolated, counted, and identified, and their in vitro antibacterial properties were determined. The results have revealed that occurrence of Gram-negative rods was around 75% and of Gram-positive rods was 25%. Among the isolates Gram-positive were maintained in nutrient agar slants at 4°C. Of these, eight strains were replica-plated on agar seeded with Aeromonas hydrophila and only one strain CM2 (C. mrigala 2) exhibited antibacterial properties in vitro showing inhibition against fish pathogen by well diffusion assay. This isolated strain was identified as Bacillus cereus. This bacterium was mass cultured and incorporated in the pelleted diet (40% protein and 18 kJ g–1 gross energy) of C. mrigala to investigate its effect on growth performance, digestibility, nutrient retention and activities of digestive enzymes. The results of feeding trial revealed significantly (P<0.05) high growth performance in terms of specific growth rate, growth percent gain in body weight (BD) (272.4±1.5)%, high apparent protein digestibility ((79.9±0.30)%) and low food conversion ratio in the group of fishes fed on diet containing B. cereus in comparison to the fishes fed on diet without probiotics. The carcass composition also revealed high accumulation of proteins ((15.28±0.15) g 100 g–1) in fishes fed on diet containing probiotics. Intestinal enzyme activities of protease, amylase and cellulase were also significantly (P<0.05) high in the group of fishes fed on diet supplemented with probiotics indicating the extracellular enzyme production by B. cereus. These results indicate that probiotics stimulate the digestion through the supply of digestive enzyme and certain essential nutrients to animals. Also significantly (P<0.05) low excretion of metabolites, i.e., ammonia excretion and phosphate production (mg kg–1 BW d–1) was observed in the fishes fed with probiotic based diets. Thus, B. cereus appears to be a promising candidate for ptobiotic applications which can enhance growth performance and nutrient retention in C. mrigala.
    Short Communication
    Parallel coordinate plots of maize traits under different magnesium applications
    Jan Bocianowski, Piotr Szulc, Kamila Nowosad
    2015, 14(3): 593-597.  DOI: 10.1016/S2095-3119(14)60852-2
    Abstract ( )   PDF in ScienceDirect  
    The parallel coordinate plot is proposed as an efficient tool for visualization of 13 traits of “stay-green” maize (Zea mays L.) cultivar exposed to different methods of magnesium application. The field experiment was conducted in the Department of Agronomy, Poznań University of Life Sciences, on the fields of the Department of Teaching and Experimental Station in Swadzim in 2006–2008. Experiment was conducted as a single-factor experiment with seven applications of magnesium in a randomized complete block design with four replicates. The highest mean values of grain yield and 1 000-grain weight were obtained after application of variant T3 of magnesium (10 kg MgO ha–1 soil) in the all three years of study.
    The complete genome sequence of Citrus vein enation virus from China
    HUANG Ai-jun, SONG Zhen, CAO Meng-ji, CHEN Hong-ming, LI Zhong-an, ZHOU Chang-yong
    2015, 14(3): 598-601.  DOI: 10.1016/S2095-3119(14)60903-5
    Abstract ( )   PDF in ScienceDirect  
    The complete nucleotide sequence of an isolate of Citrus vein enation virus (CVEV-XZG) from China has been determined for the first time. The genome consisted of 5 983 nucleotides, coding for five open reading frames (ORFs), had a similar genomic organization features with Pea enation mosaic virus (PEMV). Nucleotide and deduced amino acid sequence identity of the five ORFs compared to isolate CVEV VE-1 range from 97.1 to 99.0% and 97.4 to 100.0%, these values compared to isolate PEMV-1 range from 45.2 to 51.6% and 31.1 to 45.2%. Phylogenetic analysis based on the complete genome sequence showed that the isolate CVEV-XZG had close relationship with Pea enation mosaic virus. The results supports CVEV may be a new member of genus Enamovirus. The full sequence of CVEV-XZG presented here may serve as a basis for future study of CVEV in China.