Effect of threonine and potassium carbonate on broiler chicken performance,immunity, carcass traits,and small intestine morphology

Tropical Animal Health and Production - This study aimed to investigate the interactive effect of dietary threonine (i.e., 100, 110, and 120%) and low and high dietary potassium (i.e., 0.85 and...     

Pomegranate Growth Affected by Arbuscular Mycorrhizae,Phosphorus Fertilizer,and Irrigation Water Salinity

Pomegranate (Punica granatum L.) symbiosis with arbuscular mycorrhizae fungi (AMF) is a strategy in saline soils. In this study, two AMF (+AMF and –AMF), two phosphorus (P) fertilizer (+ P and –P), and three irrigation salinity (1, 4, and 8 dS m^?1) treatments were studied. The highest salinity level decreased the root colonization by hyphae. Plant growth parameters including shoot dry weight, leaf surface area, and plant height were negatively affected by salinity. However, the growth parameters improved in AMF treatments. Salinity decreased the shoot P concentration and increased the shoot chlorine (Cl). The root and shoot sodium (Na) concentrations were the greatest in unfertilized and P-fertilized treatments, respectively. AMF treatment improved the root and shoot P concentration and reduced the negative effect of salinity on shoot Cl concentrations. In conclusion, the effects of AMF symbiosis on growth and tissue elements concentration depend on irrigation water salinity and P fertilization.     

Changes in recovery of native and applied phosphorus with time as affected by soil properties in some calcareous soils

In an attempt to investigate variations in availability of native and applied phosphorus (P) with time, twenty five calcareous soil samples were treated with 0, 50 and 500 mg P kg^?1 soil and incubated at 80–90% of field capacity moisture content in an open door glasshouse for a period of one year. Soil samples were taken out at certain intervals for P extraction with Olsen extractant under moist condition. Results indicated that following wetting the mean value of native Olsen-P decreased initially and then increased gradually with time of incubation. Generally, the short term (24 h) recoveries were not correlated with long term ones. The recovery of added P with time was described properly by the following new proposed model: R = 100/(1 + kt^b), where R is percent recovery at time t, and k and b are empirical parameters. The values of k constant at 50 and 500 mg P kg^?1 were in the ranges of 0.40 to 1.22 (0.84 ± 0.25, on average) and 0.04 to 0.52 (0.23 ± 0.14, on average), respectively. The corresponding respective values of b constant also ranged from 0.05 to 0.32 (0.15 ± 0.06, on average) and 0.12 to 0.92 (0.46 ± 0.23, on average).     

Effects of feeding regimen of dietary Aspergillus oryzae on the growth performance,intestinal morphometry and blood profile of Nile tilapia (Oreochromis niloticus)

The current study was conducted to evaluate the feeding regimen of Aspergillus oryzae (ASP) on the growth, intestinal histomorphology and blood profile of Nile tilapia (Oreochromis niloticus). Four different ASP‐feeding regimens were evaluated, including feeding the basal diet continuously (control), feeding ASP (1 g/kg) continuously (ASPC), feeding ASP for 1 day and the next day without (ASPF1) or feeding ASP for 1 day and the two next days without (ASPF2). After 60 days, the final weight, weight gain, SGR, feed intake, protein efficiency, protein gain, body protein content, haematocrit, haemoglobin, and RBC and WBC values were increased significantly (p < 0.05) with lower glutamic‐pyruvate transaminase in ASPC group compared to the control without no difference (p > 0.05) with ASPF1‐feeding regimen. Interestingly, glutamyl oxaloacetic transaminase was significantly reduced in all feeding regimens compared to the control (p < 0.05). Protease, lipase and villi length were significantly (p < 0.05) improved in all feeding regimens compared to the control, while amylase activity increased only in ASPC group. Thus, the obtained results indicated that all ASP‐feeding regimens resulted in quite similar outcomes with respect to growth, digestive enzyme activity and intestinal histomorphology.     

Potato protoplasts in crop improvement

Clonal populations regenerated from single-leaf cell protoplasts of the potato cultivar ;Russet Burbank' display a high frequency of variation for several horticultural and disease resistance characters. Observations over a period of three tuber generations suggest stable changes in tuber shape, yield, and maturity date, in photo-period requirements for flowering, and in plant morphology. Enhanced resistance to early blight (Alternaria solani) and late blight (Phytophthora infestans) diseases also regularly occurs within regenerated populations. These findings are discussed in the context of possible application to varietal improvement, particularly as they pertain to asexually propagated plants.     

Effect of salinity and nitrogen on growth,sodium, potassium accumulation,and osmotic adjustment of halophyte Suaeda aegyptiaca (Hasselq.) Zoh

Suaeda aegyptiaca is an important native annual halophyte in salt-affected soils around coastal areas of the Persian Gulf. In order to study the effects of different levels of saturation paste soil salinity (10, 20, 40, 60, and 80 dS m^?1) and nitrogen supply (25, 50, and 75 mg kg^?1 N as urea) on growth and physiological characteristic of S. aegyptiaca, a greenhouse factorial experiment in completely randomized design was conducted with three replications. Salinity treatments were established after early growth of plants and nitrogen was applied in two steps. Results showed that increasing salinity up to 20 dS m^?1 led to increase in dry weight (DW) of plants and this decreased by increasing salinity. Also, DW of plants was significantly increased by application of 75 mg kg^?1 nitrogen. Increasing salinity significantly decreased plant height, chlorophyll index, and total nitrogen content; while proline content and total soluble solids (TSS) were significantly increased. The electrolyte leakage (EL) and sodium concentration were increased under salinity stress. However, further increase in salinity decreased these two parameters. By increasing the nitrogen levels, relative water content (RWC), chlorophyll index, proline, and total nitrogen contents were increased, whereas EL was decreased.     

Particular Distribution of Enterobacter cloacae Strains Isolated from Urinary Tract Infection within Clonal Complexes

Background:

Based on biochemical properties, Enterobacter cloacae represents a large complex of at least 13 variant species, subspecies, and genotypes that progressively identified as the most species causing hospital-acquired infections. The aim of this study was to determine the relevance between phylogenetically related strains within the E. cloacae complex and the frequency of urinary tract infection caused by them.

Methods:

A 268-bp fragment was obtained from hsp60 gene for 50 clinical E. cloacae isolates from urine cultures of inpatients that admitted to six hospitals in Tehran, Iran during December 2012 to November 2013. The 107 nucleotide sequences were analyzed and the evolutionary distances of sequences were computed and neighbor-joining tree was calculated.

Results:

It showed that all of the genetic clusters have not an equal involvement in pathogenesis of urinary tract infections. Three superior clusters were found, together representing more than two third (80%) of the isolates (cluster VI with 25 members; clusters III and VIII with 9 and 6 members, respectively) and some genetic clusters were absent (IV, X, XII, and xiii), some of which are supposed to be associated with plants and no human infection has been reported.

Conclusions:

This study, for the first time, reports the unequal contribution of E. cloacae complex subspecies and clusters in urinary tract infections in Iran and together with studies from other countries suggest that the subspecies of E.hormaechei subsp. Oharae is the most prevalent E. cloacae complex subspecies regardless of country under study. Key Words: Enterobacter cloacae complex, Urinary tract infection, hsp60     

Isolation and characterization of potassium solubilizing bacteria in some Iranian soils

The ability of a few soil bacteria to transform unavailable forms of potassium (K) to an available form is an important feature in plant growth-promoting bacteria for increasing plant yields of high-K-demand crops. In this research, isolation, screening, and characterization of six isolates of K solubilizing bacteria (KSB) from some Iranian soils were carried out. The ability of all isolates were tested in three treatments including acid-leached soil, biotite, and muscovite by analyzing the soluble K content after 5 days of incubation at 28 ± 2°C. Identification and phylogenetic analyses were also carried out by morphological, biochemical, and 16S rDNA analyses. Among the six efficient isolates, five isolates belonged to Bacillus megaterium (JK3, JK4, JK5, JK6, and JK7), while isolate JK2 belonged to Arthrobacter sp. The soluble K contents in all isolated-treatments were significantly (p < 0.01) higher than the contents in nonbacteria treatment. Herein, isolate JK2 had lower potential for K solubilization (910 mg kg^?1) compared with other isolates in acid-leached soils. The six bacterial strains showed higher solubilized K in biotite treatment than other two treatments. Overall, it can be concluded that the isolates belong to B. megaterium are the most efficient KSB under in vitro condition.