Türkiye’de Güney Anadolu Kırmızısı (GAK) Sığır Irkında DGAT1 K232A Polimorfizminin Tespiti

Öz

Türkiye'deki yerli sığır ırkları arasında Güney Anadolu Kırmızısı (GAK), yüksek süt verimi ve Akdeniz ile Güneydoğu Anadolu bölgelerinin sıcak iklimlerine güçlü adaptasyonuyla öne çıkmaktadır. Bu ırk, büyük vücut yapısı, yandan bakıldığında dikdörtgen vücut şekli ve yüksek süt verimi ile karakterize edilir ve ayrıca sıcak iklim koşullarına uyum sağlama yeteneğiyle de dikkat çekmektedir. Ek olarak, kene ve kan parazitleri gibi dış parazitlere karşı direnci nedeniyle yerel halk tarafından sıklıkla tercih edilmektedir. Yetersiz bakım ve beslenme koşullarında bile yetiştirilebilme yeteneği, ırkın pratik önemini daha da artırmaktadır. GAK sığırları ayrıca yetersiz beslenme ve yönetim koşullarında bile gelişebilme yetenekleriyle bilinmektedir. Tüy renkleri koyu kahverengiden tarçın rengine kadar değişmekte olup, laktasyon başına yaklaşık 1875 ila 4675 litre süt üretmektedirler. Süt üretimini etkileyen genetik faktörler, hayvan yetiştirme programlarında kritik bir rol oynamaktadır. Bu faktörlerden biri, süt yağının ana bileşeni olan trigliserit sentezinin son adımını katalize eden bir enzimi kodlayan Diasilgliserol O-açiltransferaz 1 (DGAT1) genidir. DGAT1 genindeki K232A polimorfizmi, süt verimi ve yağ içeriğindeki varyasyonlarla ilişkilendirilmiştir ve bu da onu süt verimi özelliklerinin seçimi için güçlü bir aday gen haline getirmektedir. Bu çalışma, Güneydoğu Türkiye'de yetiştirilen 96 GAK sığırında DGAT1 genindeki K232A polimorfizminin varlığını araştırmayı amaçlamıştır. Bulguların, bu yerli ırkın genetik yapısının daha iyi anlaşılmasına katkıda bulunması ve süt verimliliğini artırmaya odaklanan gelecekteki ıslah ve iyileştirme programları için bilimsel bir temel sağlaması beklenmektedir.

Anahtar Kelimeler

• DGAT1
• K232A polimorfizmi
• Süt verimi
• Güney Anadolu Kırmızısı

Etik Beyan

Bu çalışma, Harran Üniversitesi Hayvan Deneyleri Yerel Etik Kurulu'nun 24.12.2018 tarihli ve 2018/008/03 sayılı etik kurul onayı alınarak yürütülmüştür.

Detection of the DGAT1 K232A Polymorphism in the South Anatolian Red (SAR) Cattle Breed in Türkiye

Öz

Among the native cattle breeds in Türkiye, the South Anatolian Red (SAR) stands out due to its high milk yield and strong adaptability to the hot climates of the Mediterranean and Southeastern Anatolia regions. This breed is characterized by a large body size, a rectangular body shape when viewed from the side and high milk production, and also attracts attention with its ability to adapt to hot climate conditions. Additionally, it is frequently preferred by locals due to its resistance to external parasites such as ticks and blood parasites. Its ability to be raised even under inadequate care and feeding conditions further enhances the breed's practical importance. GAK cattle are also known for their ability to thrive under poor feeding and management conditions. Their coat color ranges from dark brown to cinnamon, and they produce approximately 1875 to 4675 liters of milk per lactation. Genetic factors influencing milk production play a critical role in animal breeding programs. One such factor is the Diacylglycerol O-acyltransferase 1 (DGAT1) gene, which encodes an enzyme that catalyzes the final step in triglyceride synthesis, the main component of milk fat. The K232A polymorphism within the DGAT1 gene has been associated with variations in milk yield and fat content, making it a strong candidate gene for dairy trait selection. This study aimed to investigate the presence of the K232A polymorphism in the DGAT1 gene in 96 SAR cattle raised in Southeastern Türkiye. The findings are expected to contribute to a better understanding of the genetic structure of this native breed and provide a scientific basis for future breeding and improvement programs focused on enhancing milk productivity.

Anahtar Kelimeler

• DGAT1
• milk yield
• K232A polymorphism
• South Anatolian red

Etik Beyan

This study was conducted with permission from the Local Ethics Committee for Animal Experiments of the Harran University, under the document dated 24.12.2018 with Decision no: 2018/008/03

Kaynakça

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