Cattle Age Prediction by Leukocytes Telomere Quantification

Abstract

Telomeres at the end of chromosomes consist of tandem repeats of (TTAGGG)n DNA sequence and associated proteins. Telomeres have the essential functions in chromosome stability and genome integrity and are hence related to cell senescence and cancer. This study was carried out to quantify the amount of telomeric DNA and establish age prediction equations by using the quantity of telomeric DNA for cattle. Analysis of the telomere quantity of the lymphocytes was performed at different age, across breeds and between different sexes of cattle. We quantified the amount of telomeric DNA by the Q-FISH technique using the telomeric DNA probe in 460 cattle at age of 1~166 months in Korean Cattle and Holstein breeds. In results, we found that the amount of telomeric DNA decreased gradually with age. The amount of telomeric DNA of Korean Cattle was significantly higher than that of Holstein breed (P<0.01). In addition, the amount of telomeric DNA in male was significantly higher than that in female (P<0.01). Using the relationship between age and the amount of telomeric DNA in cattle, age predicting equations were established as a result of regression analysis. Because sex and breeds influenced telomeric DNA quantity, the age prediction equations were estimated separately in Korean Cattle females and Holstein females. The regression equations were Ŷ = 38.102X 0.8379) in Holstein females, where the X was quantity of telomeric DNA and Y was predicted age in months. These equations predicted the age of cattle with high significance and accuracy and have high R square values. Thus, it could be possible to scientifically predict the age using the above equations for Korean Cattle and Holstein females.

Inheritance and Heritability of Telomere Length in Chicken

“…닭은 상대적으로 긴 텔로미어 길이와 분포의 다양성으로 인해 텔 로미어 연구에 무척 흥미있는 소재이지만, 지금까지 이들에 대한 텔로미어 연구는 매우 제한적으로 이루어지고 있다 (Sohn and Cho, 2010 커짐을 나타내었다. 이러한 양상은 사람 (Zeichner et al, 1999) 을 비롯한 마우스 (Kotrschal et al, 2007), 개 (Brummendorf et al, 2002), 소 (Choi et al, 2010), 돼지 등 거의 모든 동물에서 연령이 증가함에 따라 텔로미어 길이가 짧아진다. 닭의 경우에도 화이트레그혼종과 한국재래닭의 백 혈구 세포를 대상으로 연령에 따른 텔로미어 함량을 Q-FISH 방법으로 분석한 결과, 10주령 때 2.93%, 30주령 때 1.99%, 60주령 때 1.44% 및 80주령 때 1.29%로 연령이 증가함에 따 라 텔로미어 함량이 유의적으로 감소한다는 결과를 제시하 고 있다 (Kim et al, 2011).…”