Influence of monochromatic light on quality traits, nutritional, fatty acid, and amino acid profiles of broiler chicken meat.

The role of monochromatic lights was investigated on meat quality in 1-d-old straight-run broiler chicks (n = 360), divided into 6 light sources with 6 replicates having 10 chicks in each replicate. Six light sources were described as incandescent bulbs (IBL, as a control) and light-emitting diode (LED) light colors as white light (WL), blue light, red light (RL), green light, and yellow light. Among LED groups, the RL increased the concentration of monounsaturated fatty acids (P < 0.001), saturated fatty acids (P < 0.001), and the saturated:polyunsaturated fatty acid ratio (P < 0.001), but reduced the concentration of polyunsaturated fatty acid, n-3 fatty acid, and n-6 fatty acid. The IBL increased the n-3 and sulfur-containing amino acids but reduced the n-6:n-3 nonessential amino acids. The WL improved the concentration of most of the essential amino acids (P < 0.01) and nonessential amino acids (P < 0.01) of breast meat. It can be extracted that the light produced by LED responded similar to the IBL light in influencing nutrient contents of meat. Moreover, LED is not decisive in improving fatty acid composition of meat. However, the role of IBL in reducing n-6:n-3 ratio and enhancing n-3 cannot be neglected. Among LED, WL is helpful in improving essential and nonessential amino acid contents of broiler meat.

Growth performance and hematological traits of broiler chickens reared under assorted monochromatic light sources.

A study was conducted to investigate the effect of different monochromatic lights on growth performance and hematological response of growing broiler chickens. A total of 360 one-day-old broiler chicks were randomly divided into 6 lighting treatments, which were replicated 6 times with 10 chicks in each replicate. Six light treatments include incandescent bulbs (as a control) and light-emitting diode white light, blue light, red light, green light, and yellow light (YL). The birds were provided with similar nutritional specifications and environmental management facilities, except for the lights throughout the experimental period. Growth performance was evaluated in terms of BW, BW gain, feed intake, and feed conversion ratio at weekly intervals. At the end of 5 wk, 2 birds from each replicate were randomly selected for blood collection to determine hematological response. The BW and feed intake was numerically higher in YL at 5 wk of age. But interestingly, this did not result in improved feed conversion ratio in YL; nevertheless, numerical values were lower in YL at 5 wk (P > 0.05). Red blood cells, blood platelet count, and percent hematocrit were numerically higher under YL, whereas white blood cell counts and percent hemoglobin remained unaffected due to light treatments. It was concluded that monochromatic light is a potential light source that might provide a beneficial effect on growth performance but is inconclusive for hematological measures of broilers.

First report on the phylogeny of bovine norovirus in Turkey.

Bovine norovirus (BoNoV) is an important cause of diarrhea in calves and has been reported in several countries. The aims of this study were to investigate for the first time the presence of norovirus in Turkish calves by real-time reverse transcription-polymerase chain reaction (qRT-PCR) and to determine the phylogeny of any circulating strains. Fecal samples from 70 diarrheic calves were collected and analysed by SYBR Green qRT-PCR. BoNoV was detected in fecal samples from six calves. The capsid gene was partially sequenced, and phylogenetic analysis was performed. This showed that the six Turkish BoNoVs clustered with the GIII-2 prototype.

The rat brain postsynaptic density fraction contains a homolog of the Drosophila discs-large tumor suppressor protein.

In CNS synapses, the synaptic junctional complex with associated postsynaptic density is presumed to contain proteins responsible for adhesion between pre- and postsynaptic membranes and for postsynaptic signal transduction. We have found that a prominent, brain-specific protein (PSD-95) enriched in the postsynaptic density fraction from rat brain is highly similar to the Drosophila lethal(1)discs-large-1 (dlg) tumor suppressor protein. The dlg protein is associated with septate junctions in developing flies and contains a guanylate kinase domain that is required for normal control of cell division. The sequence similarity between dlg and PSD-95 suggests that molecular mechanisms critical for growth control in developing organisms may also regulate synapse formation, stabilization, or function in the adult brain.

Heteromultimerization and NMDA receptor-clustering activity of Chapsyn-110, a member of the PSD-95 family of proteins.

Chapsyn-110, a novel membrane-associated putative guanylate kinase (MAGUK) that binds directly to N-methyl-D-aspartate (NMDA) receptor and Shaker K+ channel subunits, is 70%-80% identical to, and shares an identical domain organization with, PSD-95/SAP90 and SAP97. In rat brain, chapsyn-110 protein shows a somatodendritic expression pattern that overlaps partly with PSD-95 but that contrasts with the axonal distribution of SAP97. Chapsyn-110 associates tightly with the postsynaptic density in brain, and mediates the clustering of both NMDA receptors and K+ channels in heterologous cells. Indeed, chapsyn-110 and PSD-95 can heteromultimerize with each other and are recruited into the same NMDA receptor and K+ channel clusters. Thus, chapsyn-110 and PSD-95 may interact at postsynaptic sites to form a multimeric scaffold for the clustering of receptors, ion channels, and associated signalling proteins.

The alpha subunit of type II Ca2+/calmodulin-dependent protein kinase is highly conserved in Drosophila.

A monoclonal antibody against rat brain type II Ca2+/calmodulin-dependent protein kinase (CaM kinase) precipitates three proteins from Drosophila heads with apparent molecular weights similar to those of the subunits of the rat brain kinase. Fly heads also contain a CaM kinase activity that becomes partially independent of Ca2+ after autophosphorylation, as does the rat brain kinase. We have isolated a Drosophila cDNA encoding an amino acid sequence that is 77% identical to the sequence of the rat alpha subunit. All known autophosphorylation sites are conserved, including the site that controls Ca(2+)-independent activity. The gene encoding the cDNA is located between 102E and F on the fourth chromosome. The protein product of this gene is expressed at much higher levels in the fly head than in the body. Thus, both the amino acid sequence and the tissue specificity of the mammalian kinase are highly conserved in Drosophila.

Developmental exposure to 3,4-methylenedioxymethamphetamine results in downregulation of neurogenesis in the adult mouse hippocampus.

3,4-Methylenedioxymethamphetamine (MDMA, ecstasy) is a powerful releaser of 5-HT and chronic use of this drug can cause depletion of monoamines. Recently, concerns about the risk of adult brain damage due to fetal exposure to MDMA have been raised. We investigated whether developmental MDMA exposure affected adult neurogenesis in C57 black/6 mice. MDMA (1.25 or 20 mg/kg, p.o.) or vehicle was administered daily to the mother from prenatal 6th day to postnatal 21st day. When the offspring were 11 weeks old, they were injected with 5-bromo-2'-deoxyuridine (BrdU) (120 mg/kg, i.p.) once a day for 4 days. After 24 h or 28 days, the animals were killed to count the BrdU-positive cells in the dentate gyrus. At 24 h after the last BrdU injection, the number of BrdU-positive cells in the offspring developmentally exposed to MDMA was significantly lower than that of the control group. At 28 days post-BrdU labeling, BrdU-positive cells in the dentate gyrus of female offspring with developmental exposure to high dose MDMA were significantly fewer compared with the control group. In addition, most BrdU-positive cells were co-labeled with the mature neuronal marker, neuronal nuclei, while a few BrdU-labeled cells were merged with an astrocyte marker. Our results suggest that developmental exposure to MDMA can result in decreases in the proliferation and survival of mature newborn cells in the adult dentate gyrus.

Nerve growth factor regulates gene expression by several distinct mechanisms.

To help elucidate the mechanisms by which nerve growth factor (NGF) regulates gene expression, we have identified and studied four genes (a-2, d-2, d-4, and d-5) that are positively regulated by NGF in PC12 cells, including one (d-2) which has previously been identified as a putative transcription factor (NGF I-A). Three of these genes, including d-2, were induced very rapidly at the transcriptional level, but the relative time courses of transcription and mRNA accumulation of each of these three genes were distinct. The fourth gene (d-4) displayed no apparent increase in transcription that corresponded to the increase in its mRNA, suggesting that NGF may regulate its expression at a posttranscriptional level. Thus, NGF positively regulates gene expression by more than one mechanism. These genes could also be distinguished on the basis of their response to cyclic AMP. The expression of d-2 and a-2 was increased by cholera toxin and further augmented by NGF; however, cholera toxin not only failed to increase the levels of d-5 and d-4 mRNA but also actually inhibited the NGF-dependent increase. The expression of each of these genes, including d-2 (NGF I-A), was also increased by fibroblast growth factor, epidermal growth factor (EGF), phorbol myristate acetate, and in some cases insulin, showing that the regulation of these genes is not unique to NGF. Because each of these genes was expressed in response to phorbol myristate acetate and EGF, their expression may be necessary but is certainly not sufficient for neurite formation. The protein kinase inhibitor K-252a prevented the NGF-associated, but not the acidic FGF-associated, induction of d-2 and d-5 gene expression, suggesting that these two growth factors may regulate gene expression via different cellular pathways. The study of the regulation of the expression of these and other NGF-inducible genes should valuable new information concerning how NGF and other growth factors cause neural differentiation.

Sequence changes preceding a Shine-Dalgarno region influence trpE mRNA translation and decay.

In studies with a trpE promoter-strength measuring system we observed that constructs containing the Escherichia coli trp promoter and its adjacent transcribed region yielded lower levels of trpE protein than were expected. To analyze this observation we introduced mutational changes in the nucleotide sequence preceding the trpE Shine-Dalgarno region and examined their effects on trpE mRNA synthesis, translation and decay. We found that certain deletion, insertion and substitution mutations in the pre-Shine-Dalgarno region caused a two- to fivefold increase in trpE enzyme activity. These increases were accompanied by increases in steady-state levels of trpE mRNA. Pulse-chase analyses of trpE mRNA degradation revealed that the observed steady-state trpE mRNA levels correlated with changes in trpE mRNA stability. These findings are interpreted in terms of alternative models in which the primary effect of mutational changes that elevate trpE expression is to increase trpE mRNA translation, versus increasing trpE mRNA stability.

Development of a trpE promoter-strength measuring system and its use in comparison of the trpEDCBA, trpR and aroH promoters.

An expression system was developed for measuring in vivo promoter strength at the single copy level and this system was used to compare the trp, aroH and trpR promoters. This system employs trpE enzyme activity as a measure of promoter strength and lacZ expression for internal copy number reference. Promoter-containing fragments are inserted into a cloning vector and subsequently recombined on to phage lambda by genetic exchange. Single lysogens are then prepared and used in promoter-strength analyses. The strength of several promoters was determined using this system. Among the promoters tested, the Escherichia coli trpEDCBA promoter was the strongest; it was four times more active than the lacUV5 promoter and about ten times stronger than the trpR and aroH promoters. To validate measurement of trpE enzyme activity as an indicator of promoter strength, trpE enzyme activity was compared with the level of trpE mRNA. There was excellent correspondence between the two, suggesting that with this system trpE enzyme activity accurately reflects promoter strength. We also examined a homologous promoter-strength measuring system in which the promoter-cloning plasmid lacked a 104 base-pair DNA spacer that was present immediately downstream from the promoter-cloning site in our preferred system. We found that the spacer was essential; the transcribed region accompanying a cloned promoter apparently affected trpE translational efficiency and/or trpE mRNA stability.

Reconstruction of the anterior cruciate ligament by semitendinosus tenodesis.

Rupture of the anterior cruciate ligament constitutes a major disability in young athletes and those patients with persistent disabling instability who have failed to respond to conservative treatment. A new method of reconstruction by means of semitendinsous tenodesis was used in five patients with satisfactory end results after an average follow-up of 21.4 months. Limited clinical experience indicates that with this method less anteroposterior instability persists than with other methods.

Antigenic and genomic relatedness of turkey-origin coronaviruses, bovine coronaviruses, and infectious bronchitis virus of chickens.

In earlier studies in our laboratory, we found that bovine coronavirus (BCV) was pathogenic for 1-day-old turkey poults. This finding prompted us to study the antigenic and genomic relatedness of turkey origin coronaviruses (TOCVs) to BCV. A one-step reverse transcription (RT)-polymerase chain reaction (PCR) targeting a 730-base pair fragment of the nucleocapsid (N) gene of BCV and a nested PCR targeting a 407-base pair fragment of the N gene were used in an attempt to detect TOCV from North Carolina, Indiana, and a prototype turkey coronavirus (TCV) obtained from the American Type Culture Collection. Both the one-step RT-PCR and the nested PCR amplified cell culture-passaged isolates of calf diarrhea strains of BCV but none of the 15 tested TOCVs or transmissible gastroenteritis coronavirus of swine. TOCVs also did not cross-react in a BCV antigen-capture (AC) enzyme-linked immunosorbent assay (ELISA) system with monoclonal antibodies (MAbs) against N, spike glycoprotein, and hemagglutinin esterase glycoprotein proteins of BCV as coating antibodies. The same TOCVs could be detected with primers designed from the genome of infectious bronchitis virus (IBV) of chickens. These primers amplified a 1082-base pair region spanning portions of the membrane glycoprotein (M) and N protein genes of IBV and TCV. The TOCVs also cross-reacted in an AC-ELISA with MAbs against the M and subunit 2 of spike glycoprotein of IBV.

Experimental bovine coronavirus in turkey poults and young chickens.

The DB2 calf strain of bovine coronavirus (BCV) was used to inoculate 1-day-old specific-pathogen-free (SPF) turkey poults in three trials. In all trials, the birds developed clinical signs of enteritis at 48-72 hr postinoculation. Birds euthanatized at 3, 5, and 7 days postinoculation (DPI) had flaccid, pale intestines with watery contents, and the ceca were markedly enlarged with frothy contents. Coronavirus particles were detected by immune electron microscopy with BCV antibodies from the intestinal contents of birds killed at 3, 5, 7, and 12 DPI. Body weights of inoculated poults killed at 3, 5, and 7 DPI were significantly reduced as compared with controls. Hemagglutinating antibodies were detected in sera of convalescent birds at 12 DPI. However, experimental inoculation of 1-day-old SPF chicks in two trials with the same virus resulted in no clinical signs or macroscopic or microscopic lesions. No coronaviruses were detected from intestinal contents, and there were no significant differences in body weights of inoculated and noninoculated control chicks.

Detection of transcripts of Marek's disease virus serotype 1 iCP4 homologue (MDV1 ICP4) by in situ hybridization.

Homologues of herpes simplex virus ICP4 are important genes for the activation of many herpesviruses. We detected transcripts of the Marek's disease virus serotype 1 homologue of ICP4 (MDV1 ICP4) by in situ hybridization (ISH). Using a digoxigenin-labeled-RNA (DIG-RNA) probe, MDV1 ICP4 transcripts were detected in c.a. 90% of MDV1-infected chicken embryo fibroblasts (CEF) cells when cytopathic effect was reached to 90% of the CEF cells and in 0.35% of MDCC-MSB-1 (MSB-1) cells, at a frequency similar to that for MD antigen-positive MSB-1 cells. Using the same in situ procedure, we detected abundant MDV1 ICP4 transcripts in the feather follicle epithelium (FFE) and some lymphoid cells in the liver, kidney and peripheral nerve of infected chickens. The subcellular localization of the transcripts appeared to vary: MSB-1 cells had them in the nucleus, infected CEF cells and FFE had them in the nucleus and cytoplasm, and lymphoid cells contained them in the cytoplasm. The MDV1 ICP4 transcripts were also detected in the FFE and lymphoid cells in the liver by reverse-transcriptase polymerase chain reaction (RT-PCR). Detection of MDV1 ICP4 transcripts by RT-PCR indicated the existance of MDV1 ICP4 transcripts-positive cells in these tissues. And these data suggested that DIG-RNA-ISH can detect MDV transcripts on paraffin sections and provide information about their subcellular localization.

Pathogenesis of Babesia caballi infection in experimental horses.

The present study was designed to investigate the role of cytokines in the pathogenesis of Babesia caballi in experimentally infected horses. The expression of cytokine mRNA was determined by using reverse transcription-polymerase chain reaction in two B. caballi-infected horses for 2 weeks after the infection. In one horse, there was up-regulation of interferon-gamma, tumor necrosis factor-alpha (TNF-alpha) and interleukin-2 mRNAs, while in the second horse, expression of only TNF-alpha mRNA was up-regulated. No change was observed in interleukin-4 mRNA in both of the horses. To know the relation between nitric oxide (NO) production and pathogenesis, NO production was assayed in three dexamethasone treated-B. caballi-infected horses. Production of NO in all 3 horses increased significantly before death, although the parasitemia level remained very low. Treatment with NO inhibitor resulted in the suppression of NO production and increased parasitemia level in a horse, which died of the infection. The pathological examination showed that the main cause of the death was dyspnoea and pulmonary edema. Histopathologically, diffuse global mesangial proliferative glomerulonephritis was also observed. These results suggested that NO may be a critical effector molecule of immune defense against parasite. TNF-alpha and NO might be contributing to the pathogenesis in B. caballi infection.

Metastatic intracavitary cardiac aortic body tumor in a dog.

A mobile right-ventricular mass dynamically occluding the right ostium atrioventriculare in the systolic phase was detected in a 3-year-old male Tosa dog by echocardiography. At necropsy, multiple tumor masses of various sizes were observed in the heart base right ventricular lumen, myocardium, lung and liver. Dysplasia of tricuspid valve characterized by irregular shape of leaflets, upward malposition of large papillary muscles, and shortened and stout chordae tendineae was also detected. Histopathologically, the tumor cells, arranged in sheets or nests, were polyhedral with lightly eosinophilic and finely granular cytoplasm, and contained a hyperchromatic round or oval nucleus. By Grimelius' silver stain, tumor cells had cytoplasmic positive granules. Ultrastructurally, tumor cells contained characteristic small membrane-limited granules. This is the first report of metastatic intracavitary cardiac aortic body tumor in a dog.

Retroviral sequence located in border region of short unique region and short terminal repeat of Md5 strain of Marek's disease virus type 1.

A 246-base pair (bp) retroviral sequence, which was homologous to a long terminal repeat of avian erythroblastosis virus (AEV), was detected and cloned from Md5 strain (Md5) of Marek's disease virus type 1 (MDV1) by representational difference analysis (RDA). The retroviral sequence was thought to be located in the border region of short unique region (U(s) and short terminal repeat (TRs), but did not exist in the border region of U(s) and the inverted short repeat (IRs) of the Md5 genome. A cloned fragment of the US/TRs border region of the Md5 genome showed a construction of U-E'-R-U'-E-TRs with the regions designated as follows: E, expanded TRs reported by Jones et al. [Proc. Natl. Acad. Sci. U.S.A. 90, 3855, 1993]; E', a partial copy of the expanded TRs; R, the retroviral sequence detected in Md5 genome; U, TRs-end sequence of U(s); U', a partial copy of TRs-end sequence of U(s). The sequence unit indicated as E'-R-U' was thought to be heterogeneously repeated in the Md5 genome. Since this retroviral sequence reportedly did not exist in the original stock of Md5, the retroviral sequence is thought to be inserted in the Md5 genome without experimental co-infection of avian cells with retrovirus and MDV1. These results suggest that RDA could be useful for the detection of retroviral sequences in the herpesvirus genome.

Cytology of feather pulp lesions from Marek's disease (MD) virus-infected chickens and its application for diagnosis and prediction of MD.

Cytological changes of feather pulp lesions (FPL) sampled chronologically from the same specific-pathogen free chickens inoculated with Marek's disease virus serotype 1 (MDV) were examined, comparing with their histological changes. The birds having Marek's disease (MD) lymphomas or nerve lesions exhibited the characteristic lesion changes on the cytological smears of FPL; the initial non-suppurative inflammatory to the late lymphomatous FPL. The birds having neither the MD visceral lymphomas nor the nerve lesions manifested only non-suppurative inflammatory FPL on the cytological smears throughout the experimental periods. Histological evaluation of FPL sampled from the same birds confirmed as above mentioned cytological results. From these results, the cytological evaluation of FPL proved to be an effective diagnostic and prognostic tool in foreseeing MD incidence.

Transcriptional analysis of Marek's disease virus (MDV) genes in MDV-transformed lymphoblastoid cell lines without MDV-activated cells.

Spontaneously activated MDV is rarely included in MDV-transformed cells, while it may influence the results of transcriptional analysis. A population consisting of 10(3) MDV-transformed cells probably did not include spontaneously activated MDV, since the estimated frequency of MDV-transformed cells including activated MDV was below 0.01% according to limiting-dilution polymerase chain reaction (PCR) and the presence of the major early antigen pp38 in 6 transformed cell lines. Reverse transcriptase-PCR (RT-PCR) products corresponding to ICP27, pol, TK, US3, A41, gA, gB and UL50 genes were undetectable in 10(3) cells by Southern hybridization of the RT-PCR products. Transcripts of the VP16 and SORF2 genes were detected in the 10(3) cells of MSB-1, and the pp14 gene transcript was found in 10(3) cells of RPL-1 but not in 10(3) cells of HPRS-1, MOGA-2, MSB-1 or MTB-1. A transcript corresponding to the ICP4 sequence was detected as a 0.7 kbp RT-PCR product in 10(3) cells of these MDV cell lines but not in the retrovirus-transformed 1104B1 cell line. The transcript corresponding to the 0.7 kbp RT-PCR product suggested a splice by its size and sequence. Thus, transcriptional analysis of 10(3) MDV-transformed cells revealed that the transcript corresponding to the ICP4 sequence was a common transcript in latently infected MDV-transformed cells, while most of the genes did not transcribe in these cells.

Seroprevalence of bovine immunodeficiency virus in dairy and beef cattle herds in Korea.

Infection of bovine immunodeficiency virus (BIV), a lentivirus, is thought to sporadically occur throughout the world, but seroepidemiological surveys concerning the incidence of BIV are limited and have not been undertaken in Korea. A total of 266 sera from different twenty dairy (Holstein) and twenty-six Korean native beef (Hanwoo) farms of the south-western part of Korea was analyzed for the presence of anti-BIV antibodies by Western blotting. Thirty five percent and 33% of dairy and beef cattle, respectively, were BIV-seropositive. By nested polymerase chain reaction, it was confirmed that these seropositive cows had provirus in the peripheral blood mononuclear cells. To demonstrate the correlation with BIV and bovine leukemia virus (BLV) infection, these sera were also analyzed for anti-BLV antibodies by immunodiffusion test, resulting in high prevalence of BLV infection but relatively a few dual infections. We report herein the first serological detection of antibodies to BIV in Korea.