Effects of replacing inorganic trace minerals with organic trace minerals on the production performance, blood profiles, and antioxidant status of broiler breeders.

This study was conducted to investigate the effects of replacing inorganic trace minerals (ITMs) with organic trace minerals (OTMs) on the production performance, blood profile, and antioxidative status of broiler breeders. A total of 600 healthy broiler breeder hens, aged 40 wk, were randomly divided into 5 treatments with 4 replicates in each treatment, and fed for 10 wk. Experimental treatments were: (1) commercial levels of inorganic minerals (COM); (2) L-ITM (50% of the COM, except for Se); (3) VL-OTM (37.5% of the COM, except for Se); (4) L-OTM (equivalent to L-ITM); and (5) OTM (62.5% of the COM, except for Se). The laying rate was 9.56% higher, feed-to-egg ratio was 7.83% lower, and rate of qualified eggs was 18.33% higher (P < 0.05) for L-OTM compared to L-ITM despite equal mineral levels. The fertility with COM was significantly higher (P < 0.05) than L-ITM, VL-OTM, or L-OTM treatments. OTM and COM treatments both had increased serum LH and P4. The relatively higher mineral levels fed in COM and OTM treatments increased blood total protein (P < 0.05). In addition, activities of serum GSH-Px, Mn-SOD, and T-SOD were higher (P < 0.01), while malondialdehyde (MDA) content was lower (P < 0.05), for COM and OTM birds as compared to L-ITM and VL-OTM. The serum T-SOD of L-OTM birds was significantly higher (9.81%; P < 0.01) than that of L-ITM birds. Higher (P < 0.05) activities of liver GSH-Px and T-SOD, and lower MDA concentrations (P < 0.01) were measured in the COM, L-OTM, and OTM treatments than the L-ITM treatment. Collectively, total replacement of high levels of ITMs by lower levels of OTMs in broiler breeder diets was beneficial for productive performance under the conditions of this study.

Effects of copper-loaded chitosan nanoparticles on growth and immunity in broilers.

Effects of dietary copper-loaded chitosan nanoparticle (CNP-Cu) supplementation on growth performance, hematological and immunological characteristics, and the cecal microbiota in broilers were investigated. Three hundred healthy Avian × Avian (1-d-old) broilers were randomly assigned into 5 dietary groups (20 birds per replicate with 3 replicates per group). Birds were fed with 0 (the control group), 50, 100, 150 mg/kg of CNP-Cu and 50 mg/kg chlorotetracycline (CTC, a positive control group) for 42 d. Results indicated that supplemental CNP-Cu could improve growth performance, affect the immune system, enhance protein synthesis, and be beneficial to cecal microbiota of Avian broilers, especially the dietary supplementation with 100 mg/kg of CNP-Cu. Supplementation with 100 mg/kg of CNP-Cu increased the average daily gain(P < 0.05) and the contents of IgA (P < 0.01), IgG (P < 0.01), IgM (P < 0.01), complement C3 (P < 0.05), and complement C4 (P < 0.05). Thymus, spleen, and bursa of Fabricus indexes and the populations of Lactobacillus and Bifidobacterium in cecal digesta were increased (P < 0.05) by 100 mg/kg of CNP-Cu supplementation, and the population of coliforms was decreased (P < 0.05). Dietary supplementation with 100 mg/kg of CNP-Cu increased (P < 0.05) concentrations of serum total protein and albumin, and decreased (P < 0.05) the content of urea nitrogen in serum. Effects of dietary supplementation with 100 mg/kg of CNP-Cu were similar to 50 mg/kg of CTC supplementation. These results may indicate that CNP-Cu could be a new substitute for CTC in dietary supplementation.

BCR-ABL oncogenic transformation of NIH 3T3 fibroblasts requires the IL-3 receptor.

Oncogenic transformation of hematopoietic cells by the Bcr-Abl oncoprotein directly involves the activation Jak2 tyrosine kinase and the Stat5 transcription factor. Both proteins are normally linked to the interleukin (IL)-3/granulocyte-macrophage colony-stimulating factor receptors for growth and survival. Since fibroblastic cells are not targets of BCR-ABL-induced oncogenesis, we determined whether forced expression of the IL-3 receptor would allow oncogenic transformation of NIH 3T3 fibroblasts known to be resistant to transformation by BCR-ABL. NIH 3T3 cells transduced with the human IL-3 receptor alpha and beta chains were highly susceptible to oncogenic transformation by expression of BCR-ABL. Forced expression of both receptor chains but not either one alone allowed efficient foci formation of NIH 3T3 cells expressing BCR-ABL (triple positive cells), and these cells formed colonies in soft agar, whereas BCR-ABL+ NIH 3T3 cells lacking IL-3 receptor expression did not. Signaling studies indicate that the BCR-ABL/IL-3 receptor+ NIH 3T3 cells utilize the Gab2/PI-3 kinase pathway activated by Jak2, and the Stat5 pathway activated separately by Bcr-Abl, whereas BCR-ABL+ NIH 3T3 cells lacking the IL-3 receptor do not utilize the Jak2 pathway, but still maintain activation of Stat5. The Bcr-Abl kinase inhibitor imatinib mesylate (1 microM) and two Jak2 kinase inhibitors strongly inhibited agar colony formation and the activation of Gab2 caused by Jak2. All of these findings indicate that Bcr-Abl oncoprotein requires the IL-3 receptor/Jak2/Stat5 pathways for oncogenic transformation of NIH 3T3 fibroblasts.

Transgenic GFP as a molecular marker for approaches to quantify pollination mechanism and gene flow in Arabidopsis thaliana.

Arabidopsis thaliana is commonly regarded as a self-pollinated plant. We observed that the stigma in each flower of A. thaliana cannot be pollinated by its own pollen in the early phases of the flowering process, when the anthers had dehisced but the filaments were still too short for the pollen to be deposited on the stigma. In the later stages, after elongation of the filaments, self-pollination can occur. After artificial pollination of the flower of a wild plant with GFP transgenic pollen grains in earlier stages of flowering, GFP expressed within epidermal cells was detected in some of the offspring (26.1-57.1 %). Wind-mediated pollen dispersal was poor but is likely to exist in natural habitats, while insects were observed visiting flowers of A. thaliana in natural and experimental populations. We constructed an experimental population consisting of 28 GFP transgenic plants and 240 wild plants and examined gene flow in the population. The result was that the distance of gene flow was limited to 0.5 m. 22 offspring with expressed GFP were found in 28,299 filial individuals examined, which suggested a relatively low outcrossing rate (0.74%). We conclude that outcrossing in populations of A. thaliana is mainly due to insect pollination. The data on gene flow could be useful to assess the ecological hazards of experimental transgene combinations.

Associations between single nucleotide polymorphisms in candidate genes and growth rate in Arctic charr (Salvelinus alpinus L.).

We tested for associations between single nucleotide polymorphisms (SNPs) in five candidate genes allied with the growth hormone axis and the age-specific growth rate of Arctic charr (Salvelinus alpinus L.: Salmonidae). Two large full sib families (N=217 and 95) were created by backcrossing males that were hybrids between two phenotypically divergent populations from Labrador, Canada and from Nauyuk Lake, Canada to females that were from Nauyuk Lake. Measures of individual growth rate (wet weight and fork length) were made three times during a 420-day period after the juveniles were transferred from 4 to 11 degrees C. We then identified SNP markers in 10 proposed candidate genes known to be related to the growth hormone axis. Comparative alignments of amino-acid sequences and nucleotide sequences from other fish species were used to design PCR primers that would amplify 0.5-3 kb DNA regions of the candidate genes. All the individuals in the two backcross families were genotyped for these SNP markers using either polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) or bidirectional amplification of specific alleles (Bi-PASA) approaches. A significant association between a particular SNP allele and early growth was found for the locus containing the growth hormone-releasing hormone and pituitary adenylate cyclase-activating polypeptide genes (GHRH/PACAP2, P=0.00001). We argue that using comparative sequence information to design PCR primers for candidate genes is an efficient method for locating quantitative triat loci in nonmodel organisms.

[Screening and study of RAPD markers tightly linked to wheat powdery mildew resistance gene Pm2].

The random amplified polymorphic DNA (RAPD) analysis was made in Pm2 near-isogenic lines (NILs) with 265 random primers. Seventeen out of the 256 tested primers amplified the polymorphic DNA in the NILs. Five of them showed the same discriminating results in more than four replications. The polymorphic bands were assigned to be OPM08(1600), OPI04(1700), OPH19(1100) and OPE09(900), respectively. Using these five polymorphic primers to detect 14 resistant materials with Pm2 and 9 susceptible materials without Pm2, only OPI04(1700) was amplified in 12 of the 14 resistant materials and absent in all of the 9 susceptible materials. Further RAPD analysis of (Chancellor x Ulka/8*Cc) F2 plants by primer OPI04 indicated that the genetic distance of OPI04(1700) to Pm2 was 12.2 +/- 3.3 cM.

Active-site-directed specific competitive inhibitors of phospholipase A2: novel transition-state analogues.

More than 100 amphiphilic phosphoesters, possible tetrahedral transition-state analogues capable of coordinating to the calcium ion at the active site of phospholipase A2, were designed, synthesized, and tested as inhibitors for the hydrolysis of 1,2-dimyristoyl-sn-glycero-3-phosphomethanol vesicles in the scooting mode. This assay system permits the study of structurally diverse inhibitors with phospholipase A2S from different sources, and it is not perturbed by factors that change the quality of the interface. As a prototype, 1-hexadecyl-3-trifluoroethylglycero-2-phosphomethanol (MJ33) was investigated in detail. Only the (S)-(+) analogue of MJ33 is inhibitory, and it is as effective as the sn-2 phosphonate or the sn-2 amide analogues of sn-3 phospholipids. The inhibitory potencies of the various phosphoesters depended strongly on the stereochemical and structural features, and the mole fractions of inhibitors required for 50% inhibition, X1(50), ranged from more than 1 to less than 0.001 mole fraction. The affinity of certain inhibitors for enzymes from different sources differed by more than 200-fold. The inhibitors protected the catalytic site residue His-48 from alkylation in the presence of calcium but not barium as expected if the formation of the EI complex is supported only by calcium. The equilibrium dissociation constant for the inhibitor bound to the enzyme at the interface was correlated with the XI(50) values, which were different if the inhibition was monitored in the pseudo-zero-order or the first-order region of the progress curve. These results show that the inhibitors described here interfered only with the catalytic turnover by phospholipase A2's bound to the interface, their binding to the enzyme occurred through calcium, and the inhibitors did not have any effect on the dissociation of the enzyme bound to the interface.