Effect of incorporation of ground Prosopis juliflora pods in layer diet on weight gain,egg production,and natural antibody titer in KALRO genetically improved indigenous chicken

Tropical Animal Health and Production - The potential of using Prosopis juliflora pods was evaluated as a partial replacement of energy source layer’s diets. The main objective of the...     

Trichinella: differing effects of antigens from encapsulated and non-encapsulated species on in vitro nitric oxide production

Trichinellosis is a cosmopolitan zoonotic disease affecting a wide variety of animals, including man. Non-encapsulated and encapsulated species diverge with respect to their developmental strategies. Little is known at the molecular level about parasite-derived mediators responsible for host muscle cell transformation occurring during trichinellosis. In this context, host-parasite relationships in Trichinella-infected animals could be related to different host-immune and cell mediators, e.g. nitric oxide (NO). Here, we investigate the stimulatory/inhibitory role of L1 antigens from four encapsulated (T. spiralis, T. britovi, T. nelsoni and T. nativa) and one non-encapsulated (T. pseudospiralis) Trichinella species on NO production from rat macrophages in vitro. Our results demonstrate that encapsulated and non-encapsulated Trichinella species differ in their capacity to stimulate the secretion of NO from host macrophages. Biological significance of these differences should be further assessed in the available experimental models.     

Purification and characterization of a 45-kDa concealed antigen from the midgut membranes of Ornithodoros erraticus that induces lethal anti-tick immune responses in pigs

Ornithodoros erraticus is an argasid tick that can transmit severe diseases such as human relapsing fever and African swine fever. In the search for a vaccine against this parasite, a crude extract of tick midgut membranes (GME) was obtained that in pigs and mice induced a protective response able to kill up to 80% of the nymphs in the first 72 h post-feeding and to reduce the fecundity of females by more than 50%. To identify the protective antigens, the GME was subjected to successive biochemical fractionations and the resulting simpler protein fractions were inoculated in pigs. A 45-kDa antigen, the so-called Oe45, was detected, purified and demonstrated to be responsible for the protection induced by the GME. Oe45 seems to be a membrane protein that is presumably expressed on the luminal membrane of midgut epithelial cells. Oe45 consists of at least two differently charged bands (cationic and neutral), which show antigenic cross-reactivity. The possibility that these bands might be different isoforms of the same protein is discussed. Although Oe45 is constitutively expressed at low levels throughout the trophogonic cycle, its expression is up-regulated by the ingestion of blood, as suggested by the higher levels observed between 6 and 72 h post-feeding.     

Genome sequencing analysis of Brazilian chicken anemia virus isolates that lack MSB-1 cell culture tropism

Specific amino acid (aa) substitutions in VP1, VP2 and VP3 genes were reported as a distinctive feature of the American CIA-1 strain, characterized as having a variable rate of growth and tropism for different MSB-1 cell sublines [Renshaw RW, Soiné C, Weinkle T, O'Connell PH, Ohashi K, Watson S, et al. A hypervariable region in VP1 of chicken anemia virus mediates rate of spread and cell tropism in tissue culture. J Virol 1996;70(12):8872-8]. DNA sequencing of 878 nucleotides from twelve Brazilian CAV, eight of which tested for in vitro isolation in three different sources of MDCC-MSB1 cell line and identified as lacking capacity to propagate in any of these cells, were compared to sequence data available for CAV strains propagated or not in cell culture. Alignment of the deduced aa resulted in a lack of singled out amino acid substitutions in the partial genomic sequences of Brazilian isolates that would entirely contrast them to viruses propagated in MSB-1 cells, indicating that the combined VP1, VP2 and VP3 substitutions observed may not entirely account as sole determinants of CAV isolation and propagation in MDCC-MSB-1 cells.     

Cloning and expression of chicken anemia virus VP3 protein in Escherichia coli

Purification of chicken anemia virus (CAV) VP3 protein, expressed in a prokaryotic expression system as histidine-tagged fusion protein is demonstrated in the present study. CAV particle was obtained from infected liver of chicken and DNA was extracted. The VP3 protein gene was amplified from the extracted DNA by polymerase chain reaction (PCR) and cloned. The recombinant expression construct (pTrc-VP3) was identified by PCR and sequencing analysis. Expression of VP3 protein with a molecular mass of approximately 21kDa was confirmed by Western blotting analysis with CAV-specific antibodies. The in vitro expressed VP3 protein was purified to near homogeneity by elution from the gel, as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The purified VP3 protein was recognized by CAV antibodies in a Western blotting assay. This finding indicates that recombinant VP3 expressed in the pTrcHis2 vector system can be used as antigen to detect anti-CAV antibodies.     

Effects of carvedilol treatment in dogs with chronic mitral valvular disease

BACKGROUND: Stimulation of the sympathetic nervous system occurs during the development of heart failure in dogs with chronic mitral valvular disease (CMVD). HYPOTHESIS: The use of beta-blockers to modulate the activation of the sympathetic nervous system would be useful in dogs with CMVD. ANIMALS: Group A included 13 dogs who received the conventional treatment (digoxin, benazepril, a reduced sodium diet, and codeine, and a diuretic when indicated), and group B included 12 dogs who received the protocol above plus carvedilol (0.3 mg/kg q12h). METHODS: Blinded, placebo, controlled study. RESULTS: The main echodopplercardiographic variables, heart rate, biochemical data, functional classification (FC) (New York Heart Association) and quality of life score (functional evaluation of cardiac health questionnaire) were assessed at baseline (TO) and after 3 months (T1). Only group B showed improvement in score of quality of life (13.8 +/- 8.8 versus 6.0 +/- 6.3; P < .001), in FC (2.4 - 0.9 versus 1.8 +/- 0.7; P = .032) and a reduction in systolic blood pressure (151.2 +/- 18.3 versus 124.5 +/- 23.4; P = .021). Two deaths from group A and 1 from B were related to CMVD. CONCLUSION: The studied dose of carvedilol in this group did not improve the sympathetic activation and echocardiographic variables over 3 months of chronic oral treatment. However, the results suggested a beneficial effect on the quality of life score, functional classification, and a reduction on systolic blood pressure.     

Morphological evaluation of olive germplasm present in Tuscany region

Undesirable characteristic of rapeseed oil is a relatively high level of linolenic acid (18:3), which is easily oxidized leading to rancidity and a shortened shelf life of the oil. Previous attempts to reduce linolenic acid levels in rapeseed oil through breeding have been impaired by complex genetics and strong environmental sensitivity of this trait. Therefore, our objective was to develop molecular markers for low linolenic acid that could facilitate the breeding of low linolenic rapeseed. Bulked segregant analysis was employed to identify two RAPD markers associated with 18:3 in a doubled haploid population segregating for linolenic and erucic acid levels. Based on analysis of individual DH lines, the markers RM350 and RM574, representing two independent loci, accounted for a total of 39% of the genetic variability in this population. This marker RM350 alone accounted for 25% genetic variation for this trait with no evidence of recombination. Significant interlocus interaction found between the markers RM350 and RM574 suggested that epistasis was involved in the genetic control of 18:3 level in this population. Another marker designated as RM322, which was independent of the other two, was found significantly associated with the erucic acid level and oil content. RAPD markers identified in this study should be a useful tool for the early detection of low linolenic, or low or high erucic acid genotypes in rapeseed breeding programs based on doubled haploids. This revised version was published online in July 2006 with corrections to the Cover Date.     

Intraspecific breeding for reduced glucosinolate content in Ethiopian mustard (Brassica carinata A. Braun)

A total of six Ethiopian mustard ( Brassica carinata A. Braun) lines showing reduced levels of total glucosinolate content were developed through two different approaches. In the first case, eight lines with good agronomic performance under southern-Spanish conditions were first evaluated during two years for glucosinolate content, and a pedigree selection was then performed during three further generations. The line N2-142, with an average glucosinolate content of 82 μmoles g-1 seed, was developed from the original line C-49, with an average glucosinolate content of 115 μmoles g-1 seed. In the second case, chemical mutagenesis (EMS 1% v/v) was applied to seeds from the line C- 101, with an average glucosinolate content of 125 μmoles g- 1 seed. Five mutant lines showing an average glucosinolate content between 20 and 30 μmoles g-1 seed lower than the wild line C-101 were isolated in the M_3 or M_4 generation. The reduced glucosinolate content of these mutants was confirmed by developing and analysing the M_5 generation. Previous results in B. juncea suggest that a further reduction of total glucosinolate content might be achieved through genetic recombination between the different lines developed in this work. This revised version was published online in July 2006 with corrections to the Cover Date.     

Inheritance of the stay-green trait in tropical maize

Stay-green maize genotypes have been associated with tolerance to biotic and abiotic stresses, including tolerance to drought, and to stalk and root lodging, but there is limited information on its inheritance. Thus, this research was conducted to study the inheritance of the stay-green trait using both conventional analysis and QTL mapping of the Design III in a tropical maize population developed from two inbred lines genetically divergent for this trait. Two-hundred and fifty F₂ plants were genotyped with 177 microsatellite markers, and their backcrossed progenies to both parental inbreds were evaluated at three locations. Ten plants per plot were assessed 120 days after sowing and the plot means scores for stay-green, adjusted for days to silking emergence, were used for analysis. The additive variance was larger than the dominance variance, the genetic by location interaction variance presented a high magnitude, and the heritability coefficient on a plant-basis a low magnitude. Seventeen QTL were mapped, most of them were clustered on four chromosomes and accounted for by 73.08 % of the genetic variance. About half of the QTL interacted with location, and the average level of dominance was partial dominance. The additive effects were larger than the dominance effects; the latter were not unidirectional, so that heterosis could not be exploited in crosses. Procedures for marker-assisted selection to increase the level of stay-green are discussed and an approach is suggested for using both stable and non-stable QTL in a marker-assisted backcross program.     

Evidence of Migration and Endophytic Presence of Agrobacterium tumefaciens in Rose Plants

Agrobacterium tumefaciens was isolated from stem tumors of several rose cultivars showing that the bacterium is the causal agent of aerial galls in rose plants. No differences were observed in the characteristics of the Agrobacterium isolates from crown or aerial galls. Stem inoculation of ten rose cultivars showed that all of them were susceptible to A. tumefaciens but differences in the size of the resulting tumors were observed. The movement of A. tumefaciens in rose plants was demonstrated using two wild type strains and two antibiotic resistant mutants. Three months after inoculation, the inoculated strains were recovered in the roots, crown and below and above the inoculation site but low numbers of pathogenic Agrobacterium cells were isolated. New tumors appeared in 5% of the noninoculated wounds. A. tumefaciens was isolated from the stem at different distances from the tumor in naturally infected plants. In symptomless commercial plants, the isolation from the roots, crown and at different stem levels demonstrated the existence of systemic and latent infections in rose. Direct isolation using a nonselective and selective media with or without a previous enrichment step were efficient methods for isolating tumorigenic Agrobacterium from the different parts of rose plants.