Severe Growth Depression Research Articles

Pathogenicity and virus shedding ability of fowl adenovirus serotype 4 to ducks

Fowl adenovirus serotype 4 (FAdV-4) is the pathogen causing hepatitis-hydropericardium syndrome (HHS) in broilers. Since June 2015, it has emerged as one of the leading causes of economic losses in the poultry industry in China. Although most studies on FAdV-4 have focused on its pathogenicity to broilers, limited studies have been performed on other natural hosts such as ducks and geese. In this study, we assessed the pathogenicity of FAdV-4 to ducks of different ages through intramuscular injection and found that infected ducks showed severe growth depression. The infected ducks also suffered from extensive organ damage and had histopathological changes in the liver, spleen, and kidney. Although the virus infection caused lymphocyte necrosis of immune organs and the development of the bursa of Fabricius (bursa) was inhibited, the humoral immune response of infected ducks to FAdV-4 remained strong. The infected ducks also had high viral load in tissues and shed virus after the challenge. Overall, our research demonstrates that FAdV-4 can infect ducks and adversely affect the productivity of animals. And the viruses shed by infected ducks can pose a potential risk to the same or other poultry flocks.

Glycyrrhiza glabra (Linn.) and Lavandula officinalis (L.) cell suspension cultures-based biotransformation of β-artemether

The biotransformation of β-artemether (1) by cell suspension cultures of Glycyrrhiza glabra and Lavandula officinalis is reported here for the first time. The major biotransformed product appeared as a grayish-blue color spot on thin-layer chromatography (TLC) with transparent crystal-like texture. Based on its infrared (IR) and (1)H nuclear magnetic resonance (NMR) spectra, the product was characterized as a tetrahydrofuran (THF)-acetate derivative (2). The highest conversion efficiencies of 57 and 60% were obtained when 8-9-day-old cell suspensions of G. glabra and L. officinalis were respectively fed with 4-7mg of compound 1 in 40ml of medium per culture and the cells were harvested after 2-5days of incubation. The addition of compound 1 at the beginning of the culture cycle caused severe growth depression in a dose-dependent manner, resulting in poor bioconversion efficiency of ~25% at 2-5mg/culture dose only.

Effects of EDTA, Sheep Manure Extract, and Their Application Time on Cd Uptake by Helianthus annuus from a Calcareous Mine Soil

Sunflower (Helianthus annuus L.), a potential phytoextraction plant, can accumulate high concentrations of Cd from metal-contaminated soils. Helianthus annuus was grown in a mine calcareous soil treated with increasing concentrations of EDTA (0, 0.5 and 2 g EDTA kg−1 soil) or sheep manure extract (0, 0.5 and 2 g SME kg−1 soil) 30 or 10 days before sowing (T1, T2) and 10 or 30 days after sowing (T3, T4). The EDTA application before seed germination reduced sunflower seedling emergence and dry weight. Cadmium concentrations in harvested shoots increased with EDTA concentration but the actual amount of phytoextracted Cd decreased at high EDTA concentrations, due to severe growth depression. Although application time of SME had no significant effect on shoot dry weight, it had significant effect on Cd uptake by Helianthus annuus. Applying 0.5 or 2 g SME kg−1 at T3 or T4 increased the DTPA-extractable Cd in soil and the metal concentrations accumulated in shoots and roots of sunflower. The results showed that the most efficient treatment for Cd phytoextraction by sunflower is application of 0.5 g SME per kg soil at 30 days after sowing. However, the removal efficiency of Cd from soil was very low (0.15%).

The effect of application time of mobilising agents on growth and phytoextraction of lead by Brassica napus from a calcareous mine soil

Phytoremediation of heavy metal contaminated sites is often limited by the low-bioavailability of the contaminants. Complexing agents can help to improve this technique by enhancing heavy metal solubility. Pot experiments were conducted to determine the best time for the application of ethylene diamine tetraacetic acid (EDTA) and sheep manure extract (SME) for phytoremediation of a contaminated soil by Brassica napus. The plant was grown on a mine calcareous soil treated with increasing concentrations of EDTA or SME 30 and 10 days before sowing (T1 and T2) and 10 and 30 days after sowing (T3 and T4). Soil available Pb and lead concentrations in plant organs of Brassica napus increased with EDTA concentration. The EDTA application before seed germination significantly reduced rapeseed seedling emergence and dry weight. However, the actual amount of phytoextracted Pb by rapeseed did not decrease significantly, due to severe growth depression, at high EDTA concentrations when it had applied at a suitable time (T4). SME application after sowing increased plant dry weight and Pb concentration in the soil solution and enhanced the accumulated metal concentrations in shoots and roots. Comparing the effect of EDTA and SME on Pb phytoextraction, the study showed that SME is not more effective than EDTA. The efficiency of EDTA on Pb phytoextraction by Brassica napus depends on the time of application. The most efficient treatment for Pb phytoextraction by rapeseed was application of 2 g EDTA/kg soil at T4.

Phytoextraction of lead by Helianthus annuus: effect of mobilising agent application time

Pot experiments were conducted to determine the best time for application of (ethylenediaminetetraacetic acid) EDTA and sheep manure extract (SME) in phytoremediation of a contaminated soil by <I>Helianthus annuus</I>. The plant was grown in a mine calcareous soil treated with increasing concentrations of EDTA or SME in 30 and 10 days before sowing (T1 and T2) and 10 and 30 days after sowing (T3 and T4). The best time for EDTA application was T4. The EDTA application before seed germination significantly reduced sunflower seedling emergence and dry weight. Soil available Pb and lead concentrations in plant organs increased with EDTA concentration but the actual amount of phytoextracted Pb decreased at high EDTA concentrations significantly, due to severe growth depression. SME application after sowing can increase plant dry weight and Pb concentration in the soil solution, enhancing the accumulated metal concentrations in shoots and roots. However the results showed that the most efficient treatments for Pb phytoextraction by sunflower are applications of 0.5 and 2 g EDTA/kg soil at T3 and T4, respectively.

The Organization of High-Affinity Ammonium Uptake in Arabidopsis Roots Depends on the Spatial Arrangement and Biochemical Properties of AMT1-Type Transporters

The AMMONIUM TRANSPORTER (AMT) family comprises six isoforms in Arabidopsis thaliana. Here, we describe the complete functional organization of root-expressed AMTs for high-affinity ammonium uptake. High-affinity influx of (15)N-labeled ammonium in two transposon-tagged amt1;2 lines was reduced by 18 to 26% compared with wild-type plants. Enrichment of the AMT1;2 protein in the plasma membrane and localization of AMT1;2 promoter activity in the endodermis and root cortex indicated that AMT1;2 mediates the uptake of ammonium entering the root via the apoplasmic transport route. An amt1;1 amt1;2 amt1;3 amt2;1 quadruple mutant (qko) showed severe growth depression under ammonium supply and maintained only 5 to 10% of wild-type high-affinity ammonium uptake capacity. Transcriptional upregulation of AMT1;5 in nitrogen-deficient rhizodermal and root hair cells and the ability of AMT1;5 to transport ammonium in yeast suggested that AMT1;5 accounts for the remaining uptake capacity in qko. Triple and quadruple amt insertion lines revealed in vivo ammonium substrate affinities of 50, 234, 61, and 4.5 muM for AMT1;1, AMT1;2, AMT1;3, and AMT1;5, respectively, but no ammonium influx activity for AMT2;1. These data suggest that two principle means of achieving effective ammonium uptake in Arabidopsis roots are the spatial arrangement of AMT1-type ammonium transporters and the distribution of their transport capacities at different substrate affinities.

Enhanced Phytoextraction: II. Effect of EDTA and Citric Acid on Heavy Metal Uptake by Helianthus annuus from a Calcareous Soil

High biomass producing plant species, such as Helianthus annuus, have potential for removing large amounts of trace metals by harvesting the aboveground biomass if sufficient metal concentrations in their biomass can be achieved. However, the low bioavailability of heavy metals in soils and the limited translocation of heavy metals to the shoots by most high biomass producing plant species limit the efficiency of the phytoextraction process. Amendment of a contaminated soil with ethylene diamine tetraacetic acid (EDTA) or citric acid increases soluble heavy metal concentrations, potentially rendering them more available for plant uptake. This article discusses the effects of EDTA and citric acid on the uptake of heavy metals and translocation to aboveground harvestable plant parts in Helianthus annuus. EDTA was included in the research for comparison purposes in our quest for less persistent alternatives, suitable for enhanced phytoextraction. Plants were grown in a calcareous soil moderately contaminated with Cu, Pb, Zn, and Cd and treated with increasing concentrations of EDTA (0.1, 1, 3, 5, 7, and 10 mmol kg−1 soil) or citric acid (0.01, 0.05, 0.25, 0.442, and 0.5 mol kg−1 soil). Heavy metal concentrations in harvested shoots increased with EDTA concentration but the actual amount of phytoextracted heavy metals decreased at high EDTA concentrations, due to severe growth depression. Helianthus annuus suffered heavy metal stress due to the significantly increased bioavailable metal fraction in the soil. The rapid mineralization of citric acid and the high buffering capacity of the soil made citric acid inefficient in increasing the phytoextracted amounts of heavy metals. Treatments that did not exceed the buffering capacity of the soil (<0.442 mol kg−1 soil) did not result in any significant increase in shoot heavy metal concentrations. Treatments with high concentrations resulted in a dissolution of the carbonates and compaction of the soil. These physicochemical changes caused growth depression of Helianthus annuus. EDTA and citric acid added before sowing of Helianthus annuus did not appear to be efficient amendments when phytoextraction of heavy metals from calcareous soils is considered.

Enhancement of enteropathogenic Escherichia coli pathogenicity in young turkeys by concurrent turkey coronavirus infection.

In a previous study, turkey coronavirus (TCV) and enteropathogenic Escherichia coli (EPEC) were shown to synergistically interact in young turkeys coinfected with these agents. In that study, inapparent or mild disease was observed in turkeys inoculated with only TCV or EPEC, whereas severe growth depression and high mortality were observed in dually inoculated turkeys. The purpose of the present study was to further evaluate the pathogenesis of combined TCV/EPEC infection in young turkeys and determine the role of these agents in the observed synergistic interaction. Experiments were conducted to determine 1) effect of EPEC dose, with and without concurrent TCV infection, and 2) effect of TCV exposure, before and after EPEC exposure, on development of clinical disease. Additionally, the effect of combined infection on TCV and EPEC shedding was determined. No clinical sign of disease and no attaching and effacing (AE) lesions characteristic of EPEC were observed in turkeys inoculated with only EPEC isolate R98/5, even when turkeys were inoculated with 10(10) colony forming units (CFU) EPEC (high dose exposure). Only mild growth depression was observed in turkeys inoculated with only TCV; however, turkeys inoculated with both TCV and 10(4) CFU EPEC (low dose exposure) developed severe disease characterized by high mortality, marked growth depression, and AE lesions. Inoculation of turkeys with TCV 7 days prior to EPEC inoculation produced more severe disease (numerically greater mortality, significantly lower survival probability [P < 0.05], increased frequency of AE lesions) than that observed in turkeys inoculated with EPEC prior to TCV or simultaneously inoculated with these agents. Coinfection of turkeys with TCV and EPEC resulted in significantly increased (P < 0.05) shedding of EPEC, but not TCV, in intestinal contents of turkeys. These findings indicate that TCV infection predisposes young turkeys to secondary EPEC infection and potentiates the expression of EPEC pathogenicity in young turkeys.

Effect of native arbuscular mycorrhizal fungi and Glomus mosseae on acclimatization and development of micropropagated Citrus limon (L.) Burm

SummaryArbuscular mycorrhizal fungi (AMF) have been successfully used to improve acclimatization, survival and growth of many micropropagated fruit species. In this work we tested the influence of the AM fungus Glomus mosseae (BEG 116) and that of a Sicilian native mixture of Glomus species, on the survival and growth of micropropagated lemon plants (Citrus limon (L.) Burm. ‘Zagara Bianca’) during the weaning phase to a final age of 16 months. Plantlets were obtained from embryogenic callus derived from style and stigma cultures. The native AM fungal mixture was obtained from the rhizosphere soil of a citrus grove (Sicily, Italy) and was found to be more infective than G. mosseae alone. It significantly increased plant height, root and shoot weight, leaf area, P content and shoot/root ratio at the end of the weaning phase, i.e. 17 weeks after in vivo transferring and inoculation. A severe growth depression was observed in plants inoculated with G. mosseae. During the early weaning phase, plant survival was reduced only by the native AMF mix inoculum that may still have been too rich in soil-borne pathogens; at the end of the experiment (69 weeks) plant survival was reduced by all the treatments except for the native AMF mix inoculum. A rhizosphere effect other than mycorrhizal was detected in the rhizosphere control inoculated with the sievate of the native AMF inoculum, in particular on root development. To our knowledge, this is the first report on mycorrhization of micropropagated citrus plants.

The supra-long Scots pine tree-ring record for Finnish Lapland: Part 1, chronology construction and initial inferences

This paper reviews the development of the current ‘supra-long’ pine chronology for northern Finnish Lapland. In the forest-tundra ecotone region of northern Finnish Lapland over 250 samples from living Scots pines (Pinus sylvestris L.) and over 1700 samples of subfossil pines have been collected for dendrochronological studies. In addition, over 1400 subfossils have been sampled from the forested area of Finnish Lapland. The goal of the research was to build a more than 7000-year long continuous pine ring-width chronology. The construction of the chronology is now completed. The intensive phase of the data collection and chronology building lasted about 10 years, 1989 to 1999. The major part of the Finnish Lapland master curve was con structed several years ago, but it was extremely difficult to bridge the c. 300-year gap, prior to 165 bc between the ‘absolute’ younger part of the chronology and the “‘ oating’ older part. The crucial samples were identified and assembled in the chronology in early 1999, and there is now an unbroken pine chronology about 7500 years long constructed from the subfossil forest-limit pines of northern Finnish Lapland. The severe growth depression centred on 330 bc is likely to have been caused by increased wetness. A brief summary is presented of inferred tree-line changes from the location of the samples.

Diagnosis of nitrogen deficiency and toxicity of Eucalyptus globulus seedlings by foliar analysis

The relationship between shoot growth and foliar nitrogen (N) in E. globulus seedlings was studied in the glasshouse to determine standard values for N deficiency and toxicity diagnosis. Seedlings were grown for 9 weeks in yellow sand, at 10 rates of N, applied as ammonium sulphate, calcium nitrate or ammonium nitrate. Shoot dry weight (DW) increased linearly with N rate for all forms of N in the deficiency range. Seedlings continued to respond to higher rates of ammonium and ammonium nitrate than to nitrate. Maximum shoot DW for nitrate fed plants and ammonium nitrate fed plants were 51% and 84% respectively of ammonium fed plants. Total N concentration in the youngest fully expanded leaf (YFEL) ranged from 1.0% to 3.3% in deficient and adequate plants. The critical N concentration for deficiency diagnosis (corresponding to 90% maximum yield) in the YFEL, determined from these growth response curves averaged over all N forms, was 2.6% N. For ammonium nitrate fed plants, total N concentration in the YFEL for the severely deficient, deficient, adequate, and toxic ranges were 4.3%. High total N concentrations were associated with growth depression and toxicity symptoms, which differed with N form. For nitrate fed plants, a total N concentration above 3.3% in the YFEL was associated with severe growth depression, and leaf tip necrosis. The adequate concentration range for ammonium nitrate was similar to values found on a field trial with 7 month old E. globulus trees grown on an exforest site.

Interaction between telocentric nucleolus-organizing chromosomes of two Agropyron species and their cytoplasms in alloplasmic lines of common wheat.

Alloplasmic lines of common wheat (Triticum aestivum L. cultivars `Penjamo 62' and `Siete Cerros 66') with cytoplasms of two wheatgrass species (Agropyron glaucum and Ag. trichophorum) showed severe growth depression throughout their development and male sterility at maturity. Growth vigor of the alloplasmic lines was influenced more by cytoplasm donors than by nucleus donors, while male sterility was influenced more by nucleus donors. Short-arm telocentric, nucleolus-organizing chromosomes (telosomes) derived from Agropyron caused the restoration of growth vigor and male fertility of the alloplasmic lines in which cytoplasms and telosomes from the same Agropyron species were combined. The telosomes derived from Agropyron species different from the cytoplasm donors could also recover growth vigor and male fertility of the alloplasmic lines. The result indicates the presence of a common mechanism(s) which controls the nucleus-cytoplasmic incompatibility expressed in the alloplasmic lines with the two Agropyron cytoplasms. The Agropyron telosomes showed some dosage effects on growth vigor of the alloplasmic lines and affected fertility when added to the nuclear backgrounds of the two common wheat cultivars.

Cytoplasmic diversity in alloplasmic common wheats with cytoplasms of Triticum and Aegilops revealed by photosynthetic and respiratory characteristics.

Photosynthetic and respiratory characteristics were surveyed to evaluate cytoplasmic diversities in alloplasmic common wheats in which a nuclear genome of common wheat (Triticum aestivum L. cv. Chinese Spring (CS)) was combined with cytoplasms of Triticum and Aegilops species. The photosynthetic capacity (PSC) was measured based on the 13CO2-assimilation rate by infrared absorption spectrophotometry. A significant variation was found in PSC. The alloplasmic line with a cytoplasm of T. monococcum ssp. boeoticum which is unique in causing severe growth depression and male sterility when combined with CS nuclei showed more than 30% higher PSC than the euplasmic CS. A negative correlation was found between PSC and growth vigor of the euplasmic and alloplasmic lines. Respiratory electron flows and the cytochrome c oxidase (COX) activity were measured polarographically by an oxygen electrode. The cytochrome path activity, the COX activity and the alternative path capacity showed significant variations among the lines, irrespective of plant tissues studied. The alloplasmic line with T. monococcum cytoplasm showed chracteristic respiration in the alloplasmic line: It significantly increased the alternative path capacity and the COX activity in roots and leaves of 2-week-old plants. Moreover, the COX activity in the roots was negatively correlated with growth vigor among the lines. The results suggested that the aberrantly high COX activity might be related to the growth depression of the alloplasmic CS with T. monococcum cytoplasm.

Reproduction of inclusion body hepatitis in conventionally raised chickens inoculated with a New Zealand isolate of avian adenovirus

Conventionally raised chickens were inoculated with a local isolate of serotype 8 of avian adenovirus by an oral or intraperitoneal route, or were exposed to the infection by contact. Fatal hepatitis, resembling inclusion body hepatitis, occurred in 30% and 45% of the birds inoculated by the oral and intraperitoneal routes respectively, and severe growth depression was recorded in survivors and in birds in contact. Birds which had maternally derived virus neutralising antibody titres of 64 or greater at the time of viral exposure did not succumb to fatal infection, but their growth rates were significantly depressed.

Eimeria mitis: Immunogenicity and Cross Immunity of Two Isolates

The ability of two isolates of Eimeria mitis to provide protection against homologous or heterologous challenge was examined. Based on weight gain and feed efficiency of male chickens, the B4 and C2 isolates protected against both homologous and heterologous challenge. The unprotected chickens suffered severe growth depression and impairment of feed utilization. Birds were inoculated with a series of increasing immunizing doses and became immune by the sixth dose. The C2 isolate (strain) appeared to be more immunogenic than the B4 isolate (strain).

Chronic toxicity and retention of dietary selenium fed to rats as D- or L-selenomethionine, selenite, or selenate

Groups of 8 male weanling Sprague-Dawley rats were fed for 6 weeks Torula yeast-based purified diets containing 2.5, 5.0, or 10.0 μg Se/g added as D-selenomethionine (D-SeMet), L-selenomethionine (L-SeMet), sodium selenite, or sodium selenate. All rats consuming diets containing 10.0 μg Se/g experienced severe growth depression and diet within 29 days, regardless of the form of Se fed, whereas rats fed 2.5 μg Se/g diet gave no evidence of depressed growth and survived the entire experimental period. Selenium fed as D-SeMet was retained in the tissues as strongly as L-SeMet. Skeletal muscle and heart Se concentrations were markedly greater when D- or L-SeMet were consumed than when selenite or selenate were consumed. Lesser differences due to the form of dietary Se fed were seen in the retention of Se in red blood cells, plasma, or liver. The increased deposition of Se in muscle tissues was not reflected by proportionate increases in either plasma or RBC Se, so monitoring plasma or whole blood Se may not indicate the degree of increased total Se body burden.

Incompatibility between lasalocid and chloramphenicol in broiler chicks after a long-term simultaneous administration.

Two growth experiments were conducted to evaluate in broiler chicks the compatibility between lasalocid medication in the feed (at 90 or 125 ppm) and a long-term administration of chloramphenicol either via the feed (500 ppm) or via the drinking water (500 mg/liter). The simultaneous administration of lasalocid and chloramphenicol generally caused severe growth depression, decreased feed intake and impaired feed conversion. Several chicks showed evident symptoms of intoxication, such as ataxia, leg weakness and paralysis. The development and frequency of these symptoms were dependent on the dosage of lasalocid and on the duration of the simultaneous administration. Biochemical examinations (Experiment 2) revealed in the affected chicks significant changes in several parameters, in particular a markedly increased activity of creatine kinase and GOT in the plasma. It confirmed that the observed leg weakness and paralysis were caused by myodegeneration.

The Individual and Combined Effects of Citrinin and Ochratoxin A in Broiler Chicks

Citrinin (CTN) and ochratoxin A (OA) were fed alone and in combination to broilers from day of hatch until 3 weeks of age. Dietary concentrations of 300 micrograms CTN/g and 3.0 micrograms OA/g were used. Birds fed CTN had significantly (P less than or equal to 0.05) lower body weights than controls on days 14 and 21 and increased water consumption on days 7, 14, and 21. Birds fed OA had significantly lower body weights than controls on days 7, 14, and 21 and increased water consumption on day 14. Birds fed CTN and OA in combination had lower body weights than controls and increased water consumption during the experiment, but the alterations were intermediate in severity when compared with those in birds fed CTN or OA alone. Birds fed OA alone or combined with CTN had higher liver and kidney weights than controls, but birds fed CTN alone had only higher kidney weights. Birds fed both CTN and OA had concentrations of serum constituents similar to those in birds fed OA alone, except the levels of cholesterol and triglycerides were not significantly different from those in the controls. Histological evaluation of the kidney indicated no lesions in birds fed CTN alone, but birds fed OA, alone or in combination with CTN, had increased tubular casts and tubular hyperplasia compared with controls. These data suggest that there were no additive or synergistic toxic interactions when 300 micrograms CTN/g and 3.0 micrograms OA/g were fed simultaneously to broiler chicks for 3 weeks. However, the severe growth depression resulting from OA and the increased water consumption associated with CTN toxicosis were ameliorated when CTN and OA were fed in combination. These data may be useful in diagnosing field cases of mycotoxicosis where both CTN and OA are involved.

The Interaction of Dietary Vitamin A and Vitamin D Related to Skeletal Development in the Turkey Poult

Large white male turkey poults were fed diets with different levels of vitamins A and D to study the interaction of these vitamins with regard to skeletal development. Poults fed a basal diet deficient in both vitamins A and D developed severe lameness, growth depression, mortality and lesions consistent with rickets. Birds fed a diet containing the required level of viatmin D (900 ICU/kg, NRC estimated requirement) and a high level of vitamin A (400,000 IU/kg) also developed severe lameness, growth depression and a rachiticlike condition, characterized by thicker than normal proximal tibial epiphyseal plates and lower than normal bone mineral content. When fed a diet containing the required level of vitamin A (4,000 IU/kg, NRC estimated requirement) and a high level of vitamin D (900,000 ICU/kg), poults developed hypervitaminosis D as evidenced by mild growth depression and renal tubular mineralization. When poults were fed a diet containing high levels of both vitamins A and D growth rate and bone mineral content were similar to control poults fed a diet containing the required levels of vitamins A and D. In addition, lameness and renal tubular mineralization were not apparent in the poults fed a diet containing high levels of both vitamins A and D. It was concluded that there is an antagonistic interaction between vitamins A and D.

Interrelationship of growth and plasma amino acid concentration in the chick fed casein diets as influenced by dietary protein and amino acid levels.

Chicks fed a 20% casein-sucrose diet showed severe growth depression, but dietary supplementation with 0.7% arginine-HC1, 0.35% glycine and 0.35% DL-methionine improved the growth rate to almost that of chicks fed a practical diet. Chicks fed high protein diets containing 64% casein showed normal growth, irrespective of the supplementation with such amino acids. Plasma arginine concentration of growth-retarded chicks was significantly lower than that of normal chicks. Plasma threonine/arginine ratio was negatively correlated with the growth rate of the chicks, the ratio of normal chicks being 3-4 whereas that of growth-retarded chicks was about 24. No lysine-arginine antagonism occurred under high casein feeding.