The histology and histochemical aspects of gills of the flower fish, <Emphasis Type="Italic">Pseudophoxinus antalyae</Emphasis>

Branchial epithelium of Pseudophoxinus antalyae was lined by both a thick stratified epithelium lining gill arches, gill rakers and primary filaments and a thin epithelium lining the lamellae. Mucous, chloride and rodlet cells, interspersed between pavement cells, were present in the branchial epithelium. With histochemical procedures for the characterization of glycoconjugates, mucous cells showed a strong positive reaction with Periodic acid-Shiff and Alcian Blue at pH 2.5, although with Alcian Blue at pH 0.5 and pH 1.0 the reaction was much weaker. When the combined Alcian Blue (pH 2.5) – Periodic acid-Shiff reaction was performed, most mucous cells were stained purple, whereas by the combined Aldehyde Fuchsin/Alcian Blue (pH 2.5), most cells showed a positive reaction only to Aldehyde Fuchsin. Methylation/ Alcian Blue (pH 2.5) and Methylation/ Saponification/ Alcian Blue (pH 2.5) methods showed the presence of sulphated and carboxylated glycoconjugates in mucous cells. Mucous cells were also detected to stain all metachromatically with Toluidine Blue.     

Bioaccumulation, Detection and Analyses of Heavy Metal Pollution in Sultan Marsh and Its Environment

Sultan Marsh is one of the largest and most important wetlands in Turkey, Middle East and Europe, embodying saline and fresh water ecosystems, which provide a shelter for 426 bird species. The area has begun to contribute much to the tourism of Kayseri state and its environs. However, the sites in the vicinity of the sewerage – sludge and fertilizer plants are highly damaged due to pollution. As such, studies on the heavy metal status of water, sediment and plants were investigated. Phragmites australis, Ranunculus sphaerosphermus plants and samples of sediments were taken from 13 different stations of this Marsh. All sampling sites in the study area basin were generally more or less polluted when compared with the control sites. Cr concentrations in the roots of the plants were higher than in the sediment. The tissues of Phragmites australis accumulated heavy metals more than those of Ranunculus sphaerosphermus. The heavy metal accumulation in different parts of plants followed the sequence: root > stem > leaf. Both plants can be used as biological indicators while determining environmental pressures; however, Phragmites australis proved more appropriate for such studies.     

Effect of Melatonin Implantation to Sperm Donor Rams on Post-thaw Viability and Acrosomal Integrity of Sperm Cells in the Breeding and Non-breeding Season

The influence of melatonin administration to sperm donors on the freezability of ram semen and enzyme leakage through sperm cells during different steps of the cryopreservation process were evaluated in the breeding and non-breeding season. Melatonin implantation to rams in the breeding season improved post-thaw sperm viability and intact acrosome rates without influencing the motility rate (p   < 0.05). Likewise, the post-thaw alkaline phosphatase release through sperm cells was significantly lower in the melatonin-treated group in comparison with untreated controls (p   < 0.05). In the non-breeding season, melatonin administration enhanced intact acrosome rates (p   < 0.05) and reduced aspartate aminotransferase activity (p   < 0.05) post-thaw in the offseason ejaculates. Melatonin implantation twice in the breeding and non-breeding season did not produce any further improvement in the post-thaw sperm parameters in the non-breeding season ejaculates. It was concluded that melatonin administration to sperm donors improved freezability of ram semen collected from these rams and reduced enzyme leakage through sperm cells during cryopreservation.     

Identification and expression profiles of multiple genes in Nile tilapia in response to bacterial infections

To understand the molecular mechanisms involved in response of Nile tilapia (Oreochromis niloticus) to bacterial infection, suppression subtractive cDNA hybridization technique was used to identify upregulated genes in the posterior kidney of Nile tilapia at 6h post infection with Aeromonas hydrophila. A total of 31 unique expressed sequence tags (ESTs) were identified from 192 clones of the subtractive cDNA library. Quantitative PCR revealed that nine of the 31 ESTs were significantly (p<0.05) upregulated in Nile tilapia at 6h post infection with A. hydrophila at an injection dose of 10(5)CFU per fish (≈ 20% mortality). Of the nine upregulated genes, four were also significantly (p<0.05) induced in Nile tilapia at 6h post infection with A. hydrophila at an injection dose of 10(6)CFU per fish (≈ 60% mortality). Of the four genes induced by A. hydrophila at both injection doses, three were also significantly (p<0.05) upregulated in Nile tilapia at 6h post infection with Streptococcus iniae at doses of 10(6) and at 10(5)CFU per fish (≈ 70% and ≈ 30% mortality, respectively). The three genes induced by both bacteria included EST 2A05 (similar to adenylate kinase domain containing protein 1), EST 2G11 (unknown protein, shared similarity with Salmo salar IgH locus B genomic sequence with e value of 0.02), and EST 2H04 (unknown protein). Significant upregulation of these genes in Nile tilapia following bacterial infections suggested that they might play important roles in host response to infections of A. hydrophila and S. iniae.     

Seasonal and diurnal photosynthetic behaviour of fig (Ficus carica L.) under semi-arid climatic conditions

Abstract

Diurnal and seasonal variations in net photosynthetic (P_N) and transpiration (E) rates and water use efficiency (WUE) of the fig tree (Ficus carica L.) were investigated under semi-arid climatic conditions. The two types of leaves from southern and northern parts of trees experienced natural air temperature and irradiance conditions, but differ particularly in water use efficiency. The obtained data reveal that leaf temperature, because of decrease in stomatal conductance, is the major factor limiting the gas exchange capacity of fig trees grown under rain-fed conditions. Stomatal conductance is the major control mechanism, particularly in the northern parts of the trees; however, P_N was most probably decreased by both stomatal and non-stomatal resistance mechanisms such as photoinhibition under severe drought and high irradiance conditions in the southern parts of the trees.     

Crop water stress index for potato under furrow and drip irrigation systems

Summary This study was conducted to determine the crop water stress index (CWSI) for potato (Solanum tuberosum L.) grown under furrow and drip irrigation methods and subjected to three different irrigation levels (100, 50 and 0% replenishment of soil water depleted). The lower (non-stressed) and upper (stressed) baselines were determined empirically from measurements of canopy temperatures, ambient air temperatures and vapor pressure deficit values. Tuber yield decreased when mean CWSI prior to irrigation exceeded 0.68 in furrow and 0.81 in drip irrigation. The tuber yield was directly correlated with the seasonal CWSI values and the linear equations for furrow and drip irrigation methods, Y = −45.82 CWSI + 50.69 and Y = −52.65 CWSI + 58.44, respectively, can be used for yield prediction.     

Estimates of (co)variance components for direct and maternal effects on birth weight of Karayaka lambs

The purpose of this study was to estimate the genetic parameters for birth weight of Karayaka lambs by separating direct genetic, maternal genetic, and maternal permanent environmental effects. Records of 1013 Karayaka lambs born between 2005 and 2010 were analyzed. Six different animal models were examined, all including direct additive genetic variance and various combinations of genetic and environmental maternal effects. The most appropriate model was chosen based on log-likelihood ratio tests. Since model 1 had the smallest likelihood value, it was chosen as the best model in this study. Depending on the model, direct heritability varied from 0.37 to 0.55 and maternal heritability ranged from 0.08 to 0.20 for birth weight.