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Determination of Viable Salmonella Typhimurium Cells in Heat Treated Milk By PMA/Real-Time PCR Method
2017
Zülal Kesmen | Hakiye Aslan
Applying different technological processes during the production of food has a lethal effect on the bacteria but DNA of these bacterial strains may cause false positive results when detected by real time PCR technique because they preserve their existence for a certain period of time. To overcome this shortcoming of the real time PCR technique, a new method has been developed in recent years, based on the removal of dead cell DNA from the medium by treatment with Propodium Monoazide (PMA) before DNA extraction. In this study, real-time PCR method was combined with PMA application for the detection of live cells of Salmonella Typhimurium in heat treated milk samples. For this purpose, milk samples inoculated with S. Tyhimurium were heat treated at different temperatures (60, 65, 70 and 75°C) and times (15, 60, 300, 900 sec) and number of live bacteria was determined comparatively by direct real-time PCR, PMA/real-time PCR and conventional cultural method. As a result, unlike the direct real time PCR technique, PMA/real-time PCR method prevents to a certain extent of false positive results from dead cells at all tested temperatures and times but higher results were obtained from PMA/real-time PCR method when compared to conventional cultural results. Therefore, further studies should be carried out to optimize the conditions of the PMA application in order to eliminate the high positive results detected by the PMA / real-time PCR method
Mostrar más [+] Menos [-]Risk Adjusted Production Efficiency of Maize Farmers in Ethiopia: Implication for Improved Maize Varieties Adoption
2017
Sisay Diriba Lemessa | Molla Alemayehu Yismawu | Megersa Debela Daksa | Mulugeta Damie Watabaji
This study analyzes the technical efficiency and production risk of 862 maize farmers in major maize producing regions of Ethiopia. It employs the stochastic frontier approach (SFA) to estimate the level of technical efficiencies of stallholder farmers. The stochastic frontier approach (SFA) uses flexible risk properties to account for production risk. Thus, maize production variability is assessed from two perspectives, the production risk and the technical efficiency. The study also attempts to determine the socio-economic and farm characteristics that influence technical efficiency of maize production in the study area. The findings of the study showed the existence of both production risk and technical inefficiency in maize production process. Input variables (amounts per hectare) such as fertilizer and labor positively influence maize output. The findings also show that farms in the study area exhibit decreasing returns to scale. Fertilizer and ox plough days reduce output risk while labor and improved seed increase output risk. The mean technical efficiency for maize farms is 48 percent. This study concludes that production risk and technical inefficiency prevents the maize farmers from realizing their frontier output. The best factors that improve the efficiency of the maize farmers in the study area include: frequency of extension contact, access to credit and use of intercropping. It was also realized that altitude and terracing in maize farms had influence on farmer efficiency.
Mostrar más [+] Menos [-]Adıyaman İli Badem Üreticilerinin Zirai Mücadele Uygulamalarının Değerlendirilmesi
2017
Oktay Erdoğan | Ela Tohumcu | Mehmet Fırat Baran | Osman Gökdoğan
Bu çalışmanın amacı, 2016 yılında Adıyaman ilindeki badem üreticilerinin zirai mücadele uygulamalarında karşılaştığı sorunları belirlemektir. Bu amaçla, basit tesadüfi örnekleme yöntemine göre Kahta, Besni, Gölbaşı ve Merkez ilçelerinde, her ilçede tesadüfi olarak seçilen 6 köy olmak üzere toplam 24 köyde, 96 üreticiden anket yöntemi ile bilgiler temin edilmiş ve sonuçlar yüzde oran olarak değerlendirilmiştir. Badem üreticilerinin, eğitim seviyesinin yüksek, pek çoğunun tarım dışı gelire sahip olduğu ve gelir miktarının açlık sınırı seviyesinin üzerinde olduğu saptanmıştır. Badem üreticileri pestisit seçimi ve pestisit dozunu belirlemede ilaç bayilerinden ve Tarım İl Müdürlüğünden tavsiye almakta, marka ve etkili maddenin pestisit seçiminde önemli faktörler olduğu, aynı hastalık ve zararlıya karşı sürekli aynı pestisiti kullanmadıkları, hastalık ve zararlıyı görmeden ilaçlama yaptıkları, ilaçlamada önerilen dozu uyguladıkları, kullandıkları pestisitlerin üründe kalıntı bıraktığı, ilaçlama ile hasat arasındaki bekleme süresine dikkat ettikleri, ilaçlama sırasında koruyucu elbise ve maske kullandıkları, boş pestisit kutularını tarla veya yol kenarına atmadıkları, ilaçlama aletini temizledikleri, ancak ilaçlama aletini kalibrasyon yapmadan kullandıkları, pestisitleri karışım halinde uyguladıkları, kimyasal mücadele dışında kültürel mücadeleyi tercih ettikleri ve biyopestisit kavramını bilmedikleri belirlenmiştir.
Mostrar más [+] Menos [-]Determination of Nosema Disease in Colonies of Kırşehir Province
2017
Mithat Büyük | Rahşan İvgin Tunca | Atilla Taşkın
The aim of the study was to determine the prevalence of Nosema disease caused by Nosema ceranae and Nosema apis in bee colonies in Kırşehir. A hundred worker honey bee samples were collected from each of 51 beekeepers in 31 locations in 5 provinces of Kırşehir (Centrium, Mucur, Akpınar, Boztepe and Kaman) in July 2014. A total 5100 samples were used in this study. The microscopic examinations of the study suggested that there was existence of Nosema spores in Centrium, Mucur, Akpınar and Boztepe with 25%, 23.07%, 12.5% and 60%, respectively; whereas no spores were detected in Kaman province. It was found a positive correlation between humidity and numbers of nosema spores. Molecular analyses showed that N. ceranae is only Nosema type in studied all positive samples.
Mostrar más [+] Menos [-]The General Effects of Dioxins on Livestock Feeding
2017
Süleyman Çalışlar | Mesut Karaman
Dioxins is one of the chemicals groups that cause liver toxicity, live weight reduction, immune suppression, reproductive impairments, eggshell thinning, birth defects, cancers and death in animals. The 2,3,7,8- tetrachlorodibenzo-p-dioxin (TCDD) is the most poisonous environmental chemical and many studies were showed high dosage of TCDD affects all animal group. Also TCDD increase cancer risk in human so this chemical described as carcinogenic by International Agency for Research on Cancer. Dioxins are stored in animal foods such as meat, milk, eggs and fish, because they are soluble in oil and remain in these products for many years. Dioxins can dissolve in fat and high stability therefore it can be infected to meat, milk, egg, and fish and store there for long time as a result people could be contained with dioxin during daily life. Animal feed additives such as organic acids, pH modifiers, starch, sugar, vegetable oil, fat, fruit and by-products of plant, kaolinite, rendering products, pelleting aids cause dioxin contamination. The maximum dioxin content in plant-origin feedstuffs and their by-products is 0.75 ng toxic equivalent/kg body weight. In this rewiew, the effects of dioxins on livestock feeding was examined.
Mostrar más [+] Menos [-]Modelling Chemical Preservation of Plantain Hybrid Fruits
2017
Ogueri Nwaiwu | Martin Itumoh
New plantain hybrids plants have been developed but not much has been done on the post-harvest keeping quality of the fruits and how they are affected by microbial colonization. Hence fruits from a tetraploid hybrid PITA 2 (TMPx 548-9) obtained by crossing plantain varieties Obino l’Ewai and Calcutta 4 (AA) and two local triploid (AAB) plantain landraces Agbagba and Obino l’Ewai were subjected to various concentrations of acetic, sorbic and propionic acid to determine the impact of chemical concentration, chemical type and plantain variety on ripening and weight loss of plantain fruits. Analysis of titratable acidity, moisture content and total soluble solids showed that there were no significant differences between fruits of hybrid and local varieties. The longest time to ripening from harvest (24 days) was achieved with fruits of Agbagba treated with 3% propionic acid. However, fruits of PITA 2 hybrid treated with propionic and sorbic acid at 3% showed the longest green life which indicated that the chemicals may work better at higher concentrations. The Obino l’Ewai cultivar had the highest weight loss for all chemical types used. Modelling data obtained showed that plantain variety had the most significant effect on ripening and indicates that ripening of the fruits may depend on the plantain variety. It appears that weight loss of fruits from the plantain hybrid and local cultivars was not affected by the plantain variety, chemical type. The chemicals at higher concentrations may have an effect on ripening of the fruits and will need further investigation.
Mostrar más [+] Menos [-]Doğanın Mirası: Anıt Ağaçlar
2017
Zöhre Polat
Anıt ağaçlar, doğanın mirasıdır. Anıt ağaçlar; “Yaş, çap ve boy itibariyle kendi türünün alışılmış ölçüleri üzerinde boyutlara sahip olan, yöre folklorunda, kültür ve tarihinde özel yeri bulunan, geçmiş ile günümüz, günümüz ile gelecek arasında iletişim sağlayabilecek uzunlukta doğal ömre sahip olan ağaçlardır”. Günümüzde bu ağaçların tescili, korunması ve geleceğe taşınması ile ilgili birçok araştırma yürütülmektedir. Anıt ağaçlarla ilgili ülkelerin farklı planlama ve yönetim stratejileri vardır. Bu çalışmanın amaçları; (1) Türkiye’de ağaçları anıtlaştıran özellikleri sunarak, araştırma örnekleriyle tescilleri hakkında bilgi sunmak, (2) Türkiye’de anıt ağaçların tescili, korunması ve yönetimi ile ilgili öneriler sunmaktır.
Mostrar más [+] Menos [-]Approximate Mathematical Modeling of Osmotic Dehydration of Cone-Shaped Fruits and Vegetables in Hypertonic Solutions
2017
Mohammad Sirousazar
Water loss kinetics in osmotic dehydration of cone-shaped fruits and vegetables was modeled on the basis of diffusion mechanism, using the Fick’s second law. The model was developed by taking into account the influences of the fruit geometrical characteristics, initial water content of fruit, water diffusion coefficient in fruit, and the water concentration in hypertonic solution. Based on the obtained model, it was shown that the water diffusion coefficient and the initial water concentration of fruit have direct effects on the dehydration rate and also inverse influence on the dehydration duration. The geometrical parameters of fruit and water concentration in hypertonic solution showed direct effect on the dehydration duration as well as inverse effect on the dehydration rate. The presented model seems to be useful tool to predict the dehydration kinetics of cone-shaped fruit during osmotic dehydration process and to optimize the process prior to perform the experiments.
Mostrar más [+] Menos [-]Altlık Materyalinin Etlik Piliçlerin Refah ve Performansı Üzerine Etkisi
2017
Serpil Gençoğlan | Cafer Gençoğlan
Bu çalışmanın amacı, altlık materyalinin kalitesi, çeşitleri ve bu materyalin etlik piliçlerin refah ve performansı üzerine etkilerini incelemektir. Etlik piliç yetiştiriciliğinde en uygun yetiştirme sistemi yerde yetiştiricilik olduğundan altlık materyali büyük önem kazanmaktadır. Etlik piliç üretiminde sağlanan gelişmeye bağlı olarak altlığa olan talep de artış göstermektedir. Altlık materyali olarak genelde saman, kaba odun yongası ve hızar talaşı yaygın olarak kullanılmaktadır. Bunlarla birlikte altlık materyali olarak buğday, arpa, çavdar, yulaf, ayçiçeği, çeltik, fındık, mısır, soya, fıstık, pamuk, şekerkamışı gibi malzemeler saf veya karıştırılarak kullanılmaktadır. Altlığın kalitesini altlığın nemi, pH'si, amonyum nitrat içeriği, kekleşme düzeyi ve su tutma kapasitesi belirlemektedir. İdeal altlığın nem oranı %20–25, pH değeri 8–10 arasında olmalı ve amonyak miktarı ise 25 ppm’i geçmemelidir. Altlık kalınlığı, altlığın türüne göre 2-10 cm arasında değişmekte, parça büyüklüğü de 0.6 cm’yi geçmemelidir. Altlık neminin artması pH düzeyini, NH3 konsantrasyonunu ve kekleşmeyi arttırır. Altlık materyalinin türü etlik piliçlerin performansı, refahı, sağlığı, davranışı ve ürün kalitesi üzerine etkili olmaktadır. Ayrıca bu materyallerin karkas kusurları, ayak-bacak problemleri, göğüste su toplanması, yaşama gücünde düşme, altlık nemi nedeniyle mikroorganizma gelişiminde artış, kümeslerde gaz ve toz oluşumunun artması gibi olumsuz etkileri bulunmaktadır. Bu olumsuz etkiler entansif işletmelerde büyük ekonomik kayıplara neden olmaktadır. Bu nedenle etlik piliç yetiştiriciliğinde altlık materyalinin kalitesi ve çeşidi çok önemlidir.
Mostrar más [+] Menos [-]Determination of Some Physicochemical and Microbiological Properties of Rosehip Marmalades
2017
Ayşe Özbey | Nilgün Öncül | Kader Tokatlı | Metin Yıldırım | Zeliha Yıldırım
In this study, some physicochemical and microbiological properties and antioxidant capacity of 30 rosehip marmalades produced in Tokat province by industrial or regional methods were determined. pH, water activity, viscosity, total dry content, total soluble solids, total ash, total sugar content, total ascorbic acid content and Hunter values (L*, a* and b*) were carried out to determine the physicochemical properties of samples and the means were 4.12, 0.881, 2501.6 cP, 56.12%, 56.86, 0.935%, 50.24 g/L, 173.43 mg/100g, 30.89, 10.90 and 15.11, respectively. The count of S. aureus, total and fecal coliform was not detected in any samples. The total phenolic content and TEAC were performed to investigate antioxidant capacity and the average values were 921.62 mg GAE/100 g and 66.93 µmol trolox/g.
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