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Öğe Analyzes of aflatoxin B1 and zearalenone in corn silage by high performance thin layer chromatography (HPTLC)-fluorodensitometric method(KAFKAS UNIV, VETERINER FAKULTESI DERGISI, 2012) Aydin, Hasan; Oguz, HalisIn this study development of experimented and verified method available for routine analyzes of aflatoxin B-1 (AFB(1)) and zearalenone (ZON) contamination in corn silage by High Performance Thin Layer Chromatography (HPTLC)-Fluorodensitometric method; and determination of contamination in corn silage samples collected from all of the Central Anatolia provinces by this method were aimed. The validation of both methods used in AFB(1) and ZON analyses was performed by the parameters of specificity, linearity, recovery, sensitivity and precision. In the mycotoxin analyses, the limits of sensitivity were determined 2 ppb for AFB(1) and 12 ppb for ZON. The recovery was 74% AFB(1) and 81% for ZON in corn silage. Chloroform + methanol + water development solution was used for AFB(1) analyses; and HPTLC plates were used instead of TLC plates in ZON analyses. A total of 260 corn silage samples which were the crops of the year 2007 were collected in the dairy cattle and sheep enterprises in the provinces of Aksaray, Ankara, Cankiri, Eskisehir, Karaman, Kayseri, Kirikkale, Kirsehir, Konya, Nevsehir, Nigde, Sivas and Yozgat in Central Anatolia-Turkey between the dates of March 1 and May 31, 2008; and AFB(1) and ZON levels in collected corn silage samples were analyzed. The tested and verified methods whose effectiveness was experimented on the silage samples were determined in laboratories for routine analyses. The result of toxicological analyzes, AFB(1) and ZON contamination were not detected in any of the silage samples.Öğe Heavy metal levels in farmed and wild fishes of aegean sea and assessment of potential risks to human health(KAFKAS UNIV, VETERINER FAKULTESI DERGISI, 2016) Yipel, Mustafa; Turk, Erdinc; Tekeli, Ibrahim Ozan; Oguz, HalisThe aim of this study was to determine the levels of Ag, Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in wild seabream (Sparus aurata), blotched picarel (Spicara maena), pandora (Pagellus erythrinus) fished from the Aegean Sea and the farmed seabream (Sparus aurata), and to assess the risks depending on their consumption by humans. A total of 40 fishes were collected and the metal levels were determined using ICP-OES. The metal levels were determined to be Ag (Nd), Al (3.20-8.87), Co (0.01-0.01), Cr (0.02-0.51), Cu (0.96-1.28), Fe (0.23-4.30), Mn (0.15-0.39), Ni (0.13-0.22), Pb (0.00-0.10) and Zn (6.18-7.30) (mg kg(-1) w.w.) in the study. No Ag or Cd were found in the samples. The heavy metal levels were below the national and international legal limits. The target hazard quotient (THQ) and total target hazard quotient (TTHQ) method was used to determine the possible risks of the heavy metals on human health. THQ and TTHQ values were all less than 1 and it was concluded that they do not pose any risks in terms of human health.Öğe In Vitro Activity of Toxin Binders on Aflatoxin B1 in Poultry Gastrointestinal Medium(UNIV AGRICULTURE, FAC VETERINARY SCIENCE, 2018) Yalcin, Nihayet Fadime; Avci, Tulay; Isik, Mehmet Kursat; Oguz, HalisThe purpose of this study was to determine the effectiveness of organic, inorganic and mixed toxin binders (TB) commonly used in poultry feeds to bind aflatoxin B1 (AFB1) in in vitro conditions. A total of 20 TBs, which were commonly used in the poultry industry, were divided into three groups as organic, inorganic and mix according to their contents. For each TB was used in in vitro poultry mediums both at pH 3 and 6.8 to represent proventriculus and intestine of poultry, respectively. Control groups were prepared from standard AFB1 and its dilutions; and the treatment groups were prepared from TBs (10mg) and standard AFB1 and its dilutions. After mixing and incubation periods, the samples (8 control, 6 organic, 6 inorganic and 8 mix) were analyzed in 4 replicates (2 for pH 3 and 2 for 6.8) by the method of Vicam aflatest method in HPLC-FLD after extraction and filtration processes. The binding capacity of inorganic TBs was found to be the highest, 98 and 93% at pH 3.0 and 6.8 while the organic TBs were the lowest, 40 and 45% at pH 3.0 and 6.8 respectively. Likewise, the binding capacity of mix TBs to AFB1 was found 96 and 88% at pH 3.0 and 6.8 in in vitro conditions. It was concluded that the inorganic and mix TBs were found to be effective to bind AFB1 among the TBs and could be applied to reduce the negative effects of AFB1 in poultry feeds. The organic TBs were found to be not sufficient to bind AFB1. (C) 2017 PVJ. All rights reservedÖğe Investigation of mycotoxin residues in poultry feeds by LC MS/MS method(ANKARA UNIV PRESS, 2017) Yalcin, Nihayet Fadime; Isik, Mehmet Kursat; Avci, Tulay; Oguz, Halis; Yurduseven, TuncayIn this study, it was aimed to determine the levels of mycotoxin contamination in poultry feeds in Konya, Afyonkarahisar, Aksaray and Nigde which constitutes 26.2% of the poultry production in Turkey. For this purpose a total of 73 readyto- consume poultry feed samples from poultry farms in four provinces were collected. A general screening in feeds was performed in terms of mycotoxin presence and contamination levels. Samples were analyzed for aflatoxin B-1, ochratoxin A, zearalenone, T-2 toxin, HT-2 toxin, fumonisin and deoxynivalenol levels by LC-MS/MS multi-mycotoxin method. The levels of different mycotoxins in feeds obtained from poultry farms, the proportion of positive samples and the percentage of presence in the feeds were compared in terms of maximum residue limit (MRL). It was concluded that the feeds were found to be contaminated with low rates of mycotoxins, in terms of mycotoxin types and levels in the regions screened. However, the exceeded rates were found only 1% for aflatoxin B1 (>= 5 ppb) in poultry feeds according to communique on undesirable substances in animal feed (RG 2014/11) while other mycotoxins were below the MRL.Öğe Investigation of tetracycline residues in fish caught from surrounding fish farms in Muğla district(2016) Turk, Erdinc; Oguz, HalisAmaç: Su ürünlerindeki ilaç ve metabolitlerinin kalıntı analizleri Ulusal Kalıntı İzleme Planı kapsamında düzenli olarak yapılmaktadır. Fakat Türkiye'de bu kalıntıların sucul ortama etkilerine yönelik araştırmalar sınırlıdır. Bu çalışmada, Muğla bölgesindeki balık çiftliklerinin etrafından avlanan balıklarda tetrasiklin grubu antibiyotiklerin (oksitetrasiklin, tetrasiklin, klortetrasiklin, doksisiklin) kalıntılarının belirlenmesi amaçlandı. Gereç ve Yöntem: Analiz için 70 ayrı çiftlik etrafından toplanan 70 adet balık örneği kullanıldı. Balıklarda tetrasiklin kalıntıları LC MS/MS yöntemi ile analiz edildi. Seçicilik, doğ- rusallık, geri kazanım, duyarlılık ve kesinlik ölçütlerinde metot validasyonu yapıldı. Bulgular: Analizin geri kazanımları oksitetrasiklin için %100.5, tetrasiklin için %101.3, klortetrasiklin için %99 ve doksisilin için %100.5 olarak belirlendi. Analizlerin sonucunda balık örneklerinin hiçbirinde tetrasiklin grubu antibiyotikler tespit edilemedi. Öneri: Yapılan analizlerde balık örneklerinde hesaplanabilir limitlerde tetrasiklin kalıntısı bulunmaması çevre ve halk sağlığı açısından memnuniyet verici olarak kabul edilebilir.Öğe Meta analytic study on detoxification of aflatoxin in poultry feed: an update(2016) Oguz, HalisBu meta-analitik derlemede kanatlı yemlerindeki aflatoksinlerin etkisizleştirilmesi ile ilgili yem katkısı şeklinde kullanı- lan adsorbanlar ve biyolojik ürünlerle yapılan in vivo deneysel çalışmalar özetler halinde sunuldu. Bu amaçla 39 farklı ülkede gerçekleştirilen toplam 206 araştıma tarandı ve ulaşı- lan sonuçlar ana hatlarıyla verildi. Bu derleme ile ilgili konuda yapılan tüm çalışmalar ve sonuçlarının konu ile ilgilenen sektör ve bilim temsilcilerine ülkeler bazında toplu halde sunulması ve onların bütüncül bir değerlendirme yapmalarına imkan sağlanması amaçlandı. Üreticiler ve araştırıcılar için yeme aflatoksin bağlayıcı olarak katılan yem katkısının etkinliğini belirlemede en iyi yol, aflatoksin ve aflatoksin bağlayıcı madde grubunu karşılaştırılarak elde edilen sonuç- ların performans, biyokimyasal-hematolojik, immunolojik ve makroskobik-histopatolojik verilerin hepsinin "bir bütün olarak" ele alınması ve değerlendirilmesidir. Üreticiler ve araştırıcılar denemelerin bütününe ulaşıp koruyucu maddenin pratikte kullanılabilirliğini değerlendirmek için makale başlıklarını, ortak yazarları ve/veya makalenin materyal ve metodunu takip edebilirler. Pratikteki uygulamalar için aslında, deneysel koşullar altında olumlu etkiler gösteren yem katkılarından mucizeler beklemek yerine hasat ve depolama koşullarını optimize ederek aflatoksin kontaminasyonunu sı- nırlandırılmasına odaklanmak gerekir.