Note: Molecular identification of three entomopathogenic nematodes from turkey by PCR-RFLP of the ITS regions

Molecular identification methods are widely used for the classification of organisms worldwide. Entomopathogenic nematodes are the most often isolated insect parasitic nematodes in the tropical and subtropical regions. In our investigation, PCR-RFLP (Polymerase Chain Reaction — Restriction Fragment Length Polymorphism) of the ITS region (Internal Transcribed Spacer) on the ribosomal (r) DNA of three entomopathogenic nematodes isolated from Ankara, Turkey, was analyzed for identification. The ITS region of rDNA was amplified by PCR and then digested with the following nine restriction enzymes: Alu I, Dde I, Hae III, Hha I, Hind III, Hinf I, Hpa II, Rsa I and Sau 3AI. The amplified and restricted sequences of the ITS regions were separated by agarose gel electrophoresis and the RFLP patterns of these three species were shown in this study. According to our results, these species were identified asSteinernema feltiae, Steinernema carpocapsae andHeterorhabditis bacteriophora. http://www.phytoparasitica.org posting Nov. 4, 2005.     

Evaluating the curriculum of the veterinary school of Firat University, Turkey, in terms of professional and technical skills

A significant portion of the problems faced by veterinarians is related to communication. These problems are intensely experienced between veterinary practitioners and animal owners; yet no lectures or courses aiming to improve professional skills are available in the curriculum of veterinary schools in Turkey. In this study, all students currently enrolled at, and 1992 and 1998 graduates of, the Veterinary School of Firat University (VSFU), Turkey, were surveyed to evaluate the attitudes of veterinary students and graduates toward technical and professional skills. Data were collected from 581 students and 61 recent graduates via personal interviews with students and questionnaires mailed to graduates; information was obtained about participants' technical and professional skills. The overall response rate was 85%. The results show that learning about technical and professional skills is highly valued; competence and comfort in skill sets are associated with comfort in establishing communication with instructors. Positive correlations were also noted between feeling comfortable with and feeling competent in both skill sets. In conclusion, it appears to be essential to introduce courses addressing improvement of professional skills to the curriculum of veterinary schools in Turkey, given that a successful veterinarian profile requires feeling competent in and comfortable with both technical and professional skills.     

Investigations on the light and scanning electron microscopic structure of the lingual papillae in the angora goat (Capra hircus): II. Mechanical papillae

This study was conducted to examine the light microscopy (LM) and scanning electron microscopic (SEM) structures of mechanical papillae on the tongue in the Angora goat (Capra hircus). As study materials, the tongues of four adult female Angora goats were used. The samples were collected from the dorsal surfaces of the apex, body, root and torus of the tongue and the ventral surfaces of the lingual apex for light and scanning electron microscopic examinations. Three types of mechanical papillae were seen in Angora goat tongue: papilla filiformes, papilla lentiformes and papilla conicae.The filiform papillae were detected in the dorsal surface of the tongue from lingual apex to lingual torus, and in the ventro-lateral of the lingual apex and on both sides of the lingual torus. The morphological differences were observed in filiform papillae according to their location in the tongue. The lenticular papillae settled on the centre of the lingual torus. Two types of these papillae, irregular-round and pyramid-shaped were identified. The conical papillae were scattered all over the lingual torus, except for the central part and were also seen on the root of the tongue. In the light microscopic examination, it was found that mechanical papillae had a stratified squamous epithelium and a varying degree of keratin layer on epithelial surfaces. In this study, by examining the light and scanning electron microscopic structure of the mechanical papillae in the Angora goat tongue, their similarities and differences with other domestic and wild ruminant species were determined.     

Impact of a Turkish isolate and a plaque-purified variant of SpliNPV-B on larval stage development of Spodoptera littoralis (Lepidoptera: Noctuidae) Boisd

Baculoviruses can alter the development and physiological status of their insect hosts. In the present study, two Spodoptera littoralis nucleopolyhedroviruses (SpliNPV-TR1 and SpliNPV-M2) were examined in terms of their effect on the stage development of S. littoralis at two doses/concentrations by inoculation of neonates or third instars. Both isolates had an acute pathological effect on neonates. However, larval development was prolonged (6-36 h) by either infection when neonates were infected. When third-instar larvae were inoculated, no mortality occurred until insects moulted to later stages. When the isolates were compared, more mortality occurred in the fifth instar with SpliNPV-M2 than with SpliNPV-TR1, whereas less mortality occurred in the sixth instar with SpliNPV-M2 than with SpliNPV-TR1. However, none of the isolates demonstrated a dose effect. Larvae died at 108-198 h post-inoculation at all infections, and none of them pupated. Larval development was retarded (0-126 h) for each stage when third-instar larvae were inoculated. Consequently, SpliNPV-M2 would be a more effective control agent than SpliNPV-TR1 for control of S. littoralis since it kills larvae at earlier developmental stages.     

Effects of sodium selenite on some biochemical and hematological parameters of rainbow trout (Oncorhynchus mykiss Walbaum, 1792) exposed to Pb2+ and Cu2+

This study was carried out to understand the preventive effect of selenium (Se⁴⁺) on heavy metal stress induced by lead and copper in rainbow trout (Oncorhynchus mykiss). Variation in glutathione peroxidase (Se-GSH-Px) and superoxide dismutase (SOD) activity, and in malondialdehyde (MDA) levels in liver, spleen, heart, and brain tissues of rainbow trout after 72 h of exposure to Pb²⁺ and Cu²⁺ were investigated in the presence and absence of Se⁴⁺. In the presence of Se⁴⁺, Se-GSH-Px activity and SOD activity were found to be higher and MDA levels were lower compared with in its absence. Hematological parameters were also determined and it has been observed that total leukocyte count (WBC), mean cell volume (MCV), and mean cell hemoglobin (MCH) were increased and erythrocyte number (RBC), hemoglobin (Hb), and hematocrit value (Hct; P < 0.05) were decreased in fish exposed to heavy metals in the absence of selenium. Selenium presence recovered hematological parameters to normal levels. In the light of our findings, it could be stated that Pb²⁺ and Cu²⁺ lead to dramatic changes in biochemical and hematological parameters and selenium caused these parameters to converge to control levels when it was administered concurrently with these heavy metals.     

Training System Plays a Key Role on Fruit Quality and Phenolic Acids of Sweet Cherry

In the study, the effects of different training systems (Steep Leader: SL, Spanish Bush: SB and Vogel Central Leader: VCL) on quality properties and bioactive components of “0900 Ziraat” sweet cherry fruit (Prunus avium L.) were investigated. The size, color and firmness values of the fruit varied depending on training system. The largest fruit was obtained in the SB training system. The fruit on trees trained VCL and SB had higher firmness than the fruit of trees trained SL. The color values of the fruit of VCL were higher than the other systems, while the vitamin C content was lower. The lowest acidity and soluble solids content (SSC) were measured in fruit trees trained SL. The highest values for bioactive compounds as phenolics, flavonoids were measured in fruit of SL training system. In the sweet cherry fruit, the major phenolic acid was catechin. The catechin, rutin, caffeic acid, 4?hydroxybenzoic acid, 4?aminobenzoic acid and transferulic acid content of the fruit in the SL training system were higher than those of SB and VCL. As a result, it was revealed that there is an effect of the training system on fruit quality; SB training system had higher values in terms of fruit size, whereas in terms of bioactive compound content, SL training system had higher values.

     

Identification of Corynebacterium pseudotuberculosis isolates from sheep and goats by PCR

The present study was carried out to estimate the prevalence of caseous lymphadenitis (CL) in sheep and goats slaughtered at the local abattoir in Elazig province located in the east of Turkey, between September and December 2000. A total of 2046 sheep and 2262 goat carcasses were examined during the study period and 118 abscessed lymph nodes, 89 from sheep and 29 from goats, were collected. Corynebacterium spp. strains were isolated from 81.4% of the abscesses, giving an overall prevalence of 2.2%. The prevalence was 3.5 and 1.1% in sheep and goats, respectively. PCR on DNA extracted from 96 suspicious isolates, using a pair of Corynebacterium pseudotuberculosis-specific primers, was positive for 93. Although cross-reaction with C. ulcerans, a human/bovine species, was observed, the PCR assay used in this study may successfully be applied for the diagnosis of CL in goats and sheep as an alternative to conventional methods, owing to its advantages of specificity and speed.     

The role of Pre-harvest Aminoethoxyvinylglycine (AVG) Treatments on Total Phenolics,Antioxidant Capacity and Fruit Quality Attributes of Sweet Cherry Cultivars

The present study was conducted to investigate the effects of pre-harvest aminoethoxyvinylglycine (AVG) treatments on fruit quality parameters and bioactive compounds of sweet cherry fruits (Prunus avium L. cvs. ’0900 Ziraat’, ‘Regina’ and ’Sweetheart’). Whole trees were sprayed once with an aqueous solution containing AVG (0, 100 and 200?mg L^?1) three weeks before the anticipated commercial harvest. Measurements were performed a week before anticipated harvest date, at anticipated harvest date and a week after anticipated harvest date. AVG treatments significantly maintained flesh firmness of all three sweet cherry cultivars. Harvest was delayed at least for a week through the keeping of flesh firmness with AVG treatments. The treatments slowed down the red skin color development in all three cultivars. The measurements performed over fruits collected at different ripening stages revealed that AVG resulted in decreased total phenolics and total anthocyanin and ultimately decreased antioxidant capacity in sweet cherry fruits. AVG treatments also decreased soluble solids content and increased titratable acidity of the fruits. This study revealed that pre-harvest AVG treatments were more effective in delaying sweet cherry fruit softening. The main advantage is to maintain the firmness of late-harvested fruit by retaining fruit quality attributes of sweet cherry fruit.     

Comparative biological activities of a plaque-purified variant and a Turkish native isolate of SpliNPV-B against Spodoptera littoralis (Lepidoptera: Noctuidae)

The noctuid moth Spodoptera littoralis (Boisduval) is an important pest of many cultivated plants worldwide and five different geographical Nucleopolyhedrovirus (NPV) strains of this pest have been isolated to date. Two of these, a plaque-purified variant of the S. littoralis NPV from Morocco (SpliNPV-M2) and a SpliNPV isolated from field-infected S. littoralis larvae found in Turkey (SpliNPV-TR1), were compared biologically in terms of infectiveness (median lethal dose, LD50) for third instars and in terms of virulence (median lethal time, LT50) for neonates and third-instar S. littoralis larvae. The LD50 values of SpliNPV-TR1 and SpliNPV-M2 were 20.73 and 185.21 occlusion bodies (OBs)/larva, respectively, with non-overlapping confidence limits indicating they were significantly different. Thus, SpliNPV-M2 was found to be significantly less infective (about nine times higher LD50) than SpliNPV-TR1. The LT50 values of neonates for SpliNPV-M2 and SpliNPV-TR1 were 37 and 43.9 h at a concentration of 10(6) OBs ml(-1), respectively. For these same isolates, the LT50 values at a concentration of 3 x 10(6) OBs ml(-1) were calculated as 35.6 and 41.7 h, respectively. The LT(50) values of third instars for SpliNPV-M2 and SpliNPV-TR1 were 147.4 and 160.5 h, respectively, at a dose of 3000 OBs/larva and 145.4 and 152.4 h, respectively, for the same isolates at a dose of 20,000 OBs/larva. On the other hand, Helicoverpa armigera (Hübner) and Agrotis ipsilon (Hufnagel) revealed a lack of lethality of the SpliNPV-TR1 isolate.