Orhan Karaca

Five Ovine Mitochondrial Lineages Identified From Sheep Breeds of the Near East

Archaeozoological evidence indicates that sheep were first domesticated in the Fertile Crescent. To search for DNA sequence diversity arising from previously undetected domestication events, this survey examined nine breeds of sheep from modern-day Turkey and Israel. A total of 2027 bp of mitochondrial DNA (mtDNA) sequence from 197 sheep revealed a total of 85 haplotypes and a high level of genetic diversity. Six individuals carried three haplotypes, which clustered separately from the known ovine mtDNA lineages A, B, and C. Analysis of genetic distance, mismatch distribution, and comparisons with wild sheep confirmed that these represent two additional mtDNA lineages denoted D and E. The two haplogroup E sequences were found to link the previously identified groups A and C. The single haplogroup D sequence branched with the eastern mouflon (Ovis orientalis), urial (O. vignei), and argali (O. ammon) sheep. High sequence diversity (K = 1.86%, haplogroup D and O. orientalis) indicates that the wild progenitor of this domestic lineage remains unresolved. The identification in this study of evidence for additional domestication events adds to the emerging view that sheep were recruited from wild populations multiple times in the same way as for other livestock species such as goat, cattle, and pig.

Genetic diversity in nine native Turkish sheep breeds based on microsatellite analysis

The genetic variability of 204 sheep from nine breeds (Awassi, Çine Çaparı, Karakaş, Karya, Karayaka, Morkaraman, Norduz, Sakız and Tuj) growing in four different regions (western, northern, eastern and south-eastern Anatolia) was assessed using 18 microsatellite loci. High mean number of alleles, allelic richness and factorial correspondence analysis showed the degree of admixture between native sheep breeds of Turkey. The Karya and Çine Çaparı breeds were observed as the most distinct of the breeds, and possible introgressions were detected in other breeds. It was found that 8.9% of genetic variation resulted from the difference between the populations. 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 numbers.

Bayesian inference of genetic parameters for ultrasound scanning traits of Kivircik lambs.

Ultrasound scanning traits have been adapted in selection programs in many countries to improve carcass traits for lean meat production. As the genetic parameters of the traits interested are important for breeding programs, the estimation of these parameters was aimed at the present investigation. The estimated parameters were direct and maternal heritability as well as genetic correlations between the studied traits. The traits were backfat thickness (BFT), skin+backfat thickness (SBFT), eye muscle depth (MD) and live weights at the day of scanning (LW). The breed investigated was Kivircik, which has a high quality of meat. Six different multi-trait animal models were fitted to determine the most suitable model for the data using Bayesian approach. Based on deviance information criterion, a model that includes direct additive genetic effects, maternal additive genetic effects, direct maternal genetic covariance and maternal permanent environmental effects revealed to be the most appropriate for the data, and therefore, inferences were built on the results of that model. The direct heritability estimates for BFT, SBFT, MD and LW were 0.26, 0.26, 0.23 and 0.09, whereas the maternal heritability estimates were 0.27, 0.27, 0.24 and 0.20, respectively. Negative genetic correlations were obtained between direct and maternal effects for BFT, SBFT and MD. Both direct and maternal genetic correlations between traits were favorable, whereas BFT-MD and SBFT-MD had negligible direct genetic correlation. The highest direct and maternal genetic correlations were between BFT and SBFT (0.39) and between MD and LW (0.48), respectively. Our results, in general, indicated that maternal effects should be accounted for in estimation of genetic parameters of ultrasound scanning traits in Kivircik lambs, and SBFT can be used as a selection criterion to improve BFT.

Türkiye Koyun Islahı Stratejisi

Turkiye’de ulusal anlamda bilim ve teknoloji politikalarinin olmayisi, izlenen politikalarin merkezsiz ve denetimsiz olmasina neden olmustur. Bu durum, Tarimsal Arastirma-Gelistirme (ARGE) alaninin bir bolumu olan Zootekni Alani’na da yansimistir. Bu baglamda sigir turunun gerek desteklemeler, gerekse AR-GE etkinliklerinde gerektiginden daha yuksek duzeyde one cikarildigi gozlemlenmektedir (kaldi ki, burada da desteklemelerin agirlikli olarak dev sigircilik isletmelerine yoneltildigi, kucuk ve orta olcekli isletmelerin ihmal edildigi bilinmektedir). Butun bunlarin sonucu olarak koyunda verimlilik artirilamadigi icin koyun sayisinin azalmasiyla kirmizi et ve koyun sutu uretimi ile deri sayisinda onemli dususler yasanmaktadir. Ulusal bilim ve teknoloji politikalari baglaminda Zootekni Alanindaki Ar-Ge etkinliklerinde koyunculuga onem verilmesi kacinilmaz bir zorunluluk olarak ortadadir

Hayvancılık Destekleme Politikalarına Çiftçilerin Yaklaşımlarının Bölgelerarası Karşılaştırmalı Analizi / A Regional Comparative Analysis of Farmers’ Approaches to Livestock Support Policies

OZET : Spermatogonial transplantasyon, verici bir hayvandan izole edilen spermatogonial hucrelerin bir dizi farkli yontemler kullanilarak testisleri germ hucrelerinden temizlenip infertil hale getirilmis olan alici hayvanin testislerine transfer edilmesi islemidir. Aktarilan spermatogonial hucreler kendilerini seminefer tuplerin bazal tabakasina konuslandirirlar ve spermatogenesisi baslatarak germ hucreleri tamamen bosaltilan alici hayvanin testisini yeni germ hucreleri ile doldurarak fertil bir testis meydana getirirler. Bu teknige iliskin calismalar spermatogonial kok hucrelerinin verici hayvanlardan izole edilmesi, kultur edilmesi, dondurularak saklanmasi, transplantasyon yapilmadan once alici testislerdeki spermatogonianin yok edilerek temizlenmesi, aktarilan hucrelerin alici testislerde varliginin belirlenmesi icin marker sistemlerinin gelistirilmesi ve spermatogonial transplantasyonun farkli turler arasinda uygulanisi seklinde siralanabilir. Bu teknigin ciftlik hayvanlarinda damizlik degeri belirleme zamanini azaltma, normal genetik degere sahip alici hayvanlari kisa bir sure icerisinde vericinin genetik degerine sahip germ hucresi ureten hayvanlara donusturebilme, transgenik ciftlik hayvanlari uretme gibi amaclarla yaygin olarak kullanilabilecegi ongorulmektedir. Spermatogonial transplantasyon teknigi spermatogenesis, spermatogonial kok hucreleri ve gamet-testis fonksiyonlari ve interaksiyonlarini arastirmada oldukca kullanisli bir yontemdir. Bu teknigin temel bilimden klinik uygulamalara, nesli tukenen turlerden hayvan islahina bircok alanda yararli uygulamalara yon verecegi ongorulmektedir. Anahtar kelimeler: Spermatogonial transplantasyon, testis, hayvan islahi Spermatogonial Transplantation and Its Utilization in Animal Breeding ABSTRACT : Spermatogonial transplantation is a technique which spermatogonial germ cells isolated from a donor animal are transplanted into the testes of recipient animal whose testes were depleted from germ cells. Transferred spermatogonial germ cells translocate themselves to the base of semineferous tubules, repopulate the germ-cell depleted testes of recipient animal by reinitiating spermatogenesis and restore the fertility. Isolation, culture and cryopreservation of spermatogonial stem cells from donor animals, depleting the germ cells of recipient testes prior to transplantation, developing marker systems to determine donor derived spermatogonia in the recipient testes and interspecies transplantation could be considered as the main topics of spermatogonial transplantation studies carried out so far. This technique is speculated to be used for various purposes such as decreasing the time needed to prove the genetic value of the livestock animals, converting the genetically average recipient animals into genetically superior germ cell producing animals in a short time and generating transgenic livestock. Spermatogonial transplantation is a useful technique to be used in investigating spermatogenesis, spermatogonial stem cells, gamete-testis functions and interactions. It is thought that this technique can be utilized in a variety of the areas such as basic science, clinical applications, endangered species and animal breeding. Key words: Spermatogonial transplantation, testis, animal breeding