Yerli koyun ırklarında bulunan genetik çeşitlilik

TÜBİTAK TBAG01.12.2004Bu çalışmada, Türk koyun ırklarında mevcut genetik çeşitlilik 5 mikrosatelit lokusu kullanılarak incelenmiştir. Devlet üretim çiftlikleri, üniversite üretim çiftlikleri ve yerel yetiştiricilerin elinde bulunan sürülerden yerli ve melez onbir Türk ırkı (Akkaraman, Morkaraman, Kıvırcık, İvesi, Dağlıç, Karayaka, Hemşin, Norduz, Kangal, Konya Merinosu, Türkgeldi) ile bireyleri Irak'tan getirilmiş yabancı bir ırkı (Hamdani) temsil eden toplam 423 birey bu çalışmada kullanılmıştır. Bazı ırklar icin birden fazla örnekleme yapılmıştır. Genetik varyasyonun ölçütlerinden beklenen heterozigotluk (HE) 0.686 ile 0.793 arasında, ortalama gözlenen allel sayıları (OAS) ise 5.8 ile 11.8 arasında değişmiştir. Türkiye üzerinde allel frekans dağılımları, evcilleşme merkezlerinden olmuş olabilecek göçlerle beklenen, dogudan batıya geçişli bir değişim göstermemiştir. FST indeksi Akkaraman, Karayaka ve Dağlıç'ta aynı ırkın farklı örneklemelerindeki farklılaşmayı ölçmek için kullanılmıştır ve yetiştirme çiftliğinden alınan Akkarman1'in diğer iki Akkaraman populasyonundan istatistiki önemle (P<0.001) farklı olduğu bulunmuştur. FIS indeksi ile ırklar Hardy-Weinberg (H-W) dengesi açısından test edilmiş, Akkaraman1, İvesi, Morkaraman ve Hemşin'de H-W'den sapma tespit edilmiştir. AMOVA analizi toplam genetik varyasyonun büyük bir kısmının (~% 95) ırk içi bireyleri arasında olduğunu göstermiştir. Parallel sonuçlar ırk ve bireyleri arası genetik ilişkinin incelendiği faktöriyel benzerlik analizi ve allel paylaşım uzaklığı ile de elde edilmiş ve genellikle, ırklar arası belirgin bir fark görülmemiştir. DA genetik uzaklığı ile çizilen komşu birleştirme ağacı ve temel öğeler analizi ise ırklar ve çeşitli örnekleri arası farklılaşmayı incelemek için kullanılmıştır. Özellikle ilk analiz çiftlik örneklerinin farklı olduğunu göstermiştir. Delaunay ağı ırklar arasında 4 adet (ikisi coğrafi bariyer ile paralel) genetik sınır belirlemiştir. Sonuçların hepsi Kıvırcık ırkının diğerlerinden çok farklı olduğu yönündedir. Mantel testi ve Darboğaz testi istatistiksel olarak anlamlı bir sonuç ortaya koymamıştır. Avrupa ırklarının çoğuna genetik olarak en yakın bulunan Kıvırcık örneği olmuştur. Türk ırklarında Avrupa ırklarından yüksek fakat çok da farklı olmayan bir genetik çeşitlilik belirlenmiştir. Bunda son yıllarda koyun sayısında, Türkiye’de, yaşanan hızlı düşüş etkili olmuş olabileceği düşünülmüştür.In this study the genetic diversity in Turkish native sheep breeds was investigated based on fıve microsatellite loci. In total, 423 individuals from 11 native and crossbred Turkish sheep breeds (Akkaraman, Morkaraman, Kıvırcık, İvesi, Dağlıç, Karayaka, Hemşin, Norduz, Kangal, Konya Merinosu, Türkgeldi) and one Iraqi breed (Hamdani) were analyzed by sampling from breeding farms and local breeders. For some of the breeds sampling was done more than once. Genetic variation within breeds was estimated by expected heterozygosity (HE), which ranged between 0.686 and 0.793 and by the mean number of observed alleles (MNA), it ranged between 5.8 and 11.8. The allele frequency distribution across Turkey showed no gradient from east to west, gradient was expected in accordance with the migrations from the domestication centers. The differentiation between different samples of Akkaraman, Dağlıç and Karayaka breeds was tested by FST index. Akkaraman1 sample from the breeding farm was significantly (P<0.001) different from the other two Akkaraman samples. Deviation from Hardy-Weinberg expectations observed for Akkaraman1, İvesi, Morkaraman and Hemşin breeds. AMOVA analysis revealed that most of the total genetic variation (~95%) was within the individuals of the breeds. In parallel to this observation, when factorial correspondence analysis and shared alleles distances were used to analyze the relationship between the breeds and their individuals, generally, there were no clear discriminations between the breeds. Moreover, neighbour joining tree constructed based on DA genetic distance, and principle component analysis were used to analyze among breed differentiation. The former one emphasized the genetic distinctness of the farm samples. Delaunay network drew 4 genetic boundaries (two of them being parallel to geographic boundaries) between the breeds. All the results indicated that Kıvırcık was the most differentiated breed. Finally, Mantel Test and Bottleneck analysis did not reveal a significant result. Kıvırcık breed, among all native Turkish breeds, was found to be the genetically closest to the European breeds based on the loci analyzed. The genetic variation in Turkish breeds was not much higher than that of European breeds, which might be a consequence of the recent sharp decrease in sheep number, in Turkey

MyoPS A Benchmark of Myocardial Pathology Segmentation Combining Three-Sequence Cardiac Magnetic Resonance Images

Assessment of myocardial viability is essential in diagnosis and treatment management of patients suffering from myocardial infarction, and classification of pathology on myocardium is the key to this assessment. This work defines a new task of medical image analysis, i.e., to perform myocardial pathology segmentation (MyoPS) combining three-sequence cardiac magnetic resonance (CMR) images, which was first proposed in the MyoPS challenge, in conjunction with MICCAI 2020. The challenge provided 45 paired and pre-aligned CMR images, allowing algorithms to combine the complementary information from the three CMR sequences for pathology segmentation. In this article, we provide details of the challenge, survey the works from fifteen participants and interpret their methods according to five aspects, i.e., preprocessing, data augmentation, learning strategy, model architecture and post-processing. In addition, we analyze the results with respect to different factors, in order to examine the key obstacles and explore potential of solutions, as well as to provide a benchmark for future research. We conclude that while promising results have been reported, the research is still in the early stage, and more in-depth exploration is needed before a successful application to the clinics. Note that MyoPS data and evaluation tool continue to be publicly available upon registration via its homepage (www.sdspeople.fudan.edu.cn/zhuangxiahai/0/myops20/)

Effect of dietary protein on the growth of mullet, Chelon labrosus, reared in sea cages

The purpose of the study was to obtain preliminary data on the effect of dietary protein on the growth of the thick-lipped grey mullet (Chelon labrosus) juveniles reared in net sea-cages. The juveniles (6.2 ± 0.61 g) were obtained from the wild and were stocked into net sea-cages at a stocking rate of 100 juveniles per cubic meter and fed with experimental diets including 25, 30, or 35% crude protein for 87 days. The highest mean weight and specific growth rate (SGR) were 39.5 g and 2.13% day-1, respectively, at protein levels of 30%. The diet also resulted in the most efficient feed conversion ratio of 1.61. © 2017 Archives of Polish Fisheries