Animal Breeding and Genetics
Staff
Research Topics
The aim of animal breeding and genetics is to investigate invisible genetic events using statistical and molecular genetics analysis. Then we can understand the genetic structure of a population and the genetic features of an animal, which is useful for designing an optimum breeding program. In particular, we are interested in genetic analysis of reproductive traits in Japanese Black cattle, the genetic diversity in the animal population and theory of QTL (Quantitative traits locus) analysis. Through our research activity, young scientists are encouraged to acquire the necessary knowledge and techniques to pursue scientific careers in quantitative genetics in the post-genome era.
Genetic parameters for calf mortality in Japanese Black cattle
The Japanese Black cattle is the predominant beef breed in Japan. In Japan, calves are sold at action, so, the death of calves is an economic loss for the reproductive farm. In spite of the economic importance of calf mortality, studies of the genetic parameters of calf mortality are few. Because, calf mortality is not a continuous trait such as body weight, but a threshold trait, classified only as live or dead. However, in recent years, the genetic parameters of threshold traits can be analyzed. Therefore, we investigate the genetic parameters of calf mortality in Japanese Black cattle. |
Genetic parameters for reproduction traits in Japanese Black cattle
In recent years, Japanese Black cattle have been selected mainly for their meat quality, especially the degree of (intramuscular) marbling. In practice, genetic improvement for meat quality is very high. On the other hand, fertility performance is falling. Therefore, it is very important for genetic improvement of fertility performance to investigate the genetic parameters for reproduction traits and the genetic correlation between reproduction traits and carcass traits in Japanese Black cattle. Moreover, we investigate the genes responsible for reproduction traits with another institute. |
Genetic diversity in Japanese Black cattle
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As mentioned above, genetic improvement for meat quality in Japanese Black is very high. A small number of elite sires with high estimated breeding values for meat quality have been intensively used. As a result, the effective population size of the breed has decreased during recent decades. Therefore, the increase of the effective population size to maintain the high levels of genetic diversity is important for maintaining future breeding options in this breed, since genetic diversity is essential for maintaining selection response to increase productivity and to adapt to economic and environmental changes. Therefore, we investigated the genetic diversity of Japanese Black cattle using genetic markers. |
Publication List
- Ibi,T., Kahi, A. K., and Hirooka, H., (2015) Genetic parameters of postnatal mortality and birth weight in Japanese Black calves. Animal Science Journal, 86, 25-30.
- Sasaki, S., Ibi, T., Matsuhashi, T., Takeda, K., Ikeda, S., Sugimoto, M., and Sugimoto, Y., (2015) Genetic variants in the upstream region of activin receptor IIA are associated with female fertility in Japanese Black cattle. BMC Genetics , 16, 123-136.
- Takahiro NISHIMAKI, Takayuki IBI, SIQINTUYA, Naohiko KOBAYASHI, Tamako MATSUHASHI, Takayuki AKIYAMA, Emi YOSHIDA, Kazumi IMAI, Mayu MATSUI, Keiichi UEMURA, Hisayoshi ETO, Naoto WATANABE, Tatsuo FUJITA, Yosuke SAITO, Tomohiko KOMATSU, Hiroshi HOSHIBA, Hideyuki MANNEN, Shinji SASAZAKI and Tetsuo KUNIEDA.(2016).Allelic frequencies and association with carcass traits of six genes in local subpopulations of Japanese Black cattle.Animal Science Journal 87, 469–476
- Sasaki S, Ibi T, Akiyama T, Fukushima M, Sugimoto Y.(2016) .Loss of maternal ANNEXIN A10 via a 34-kb deleted-type copy number variation is associated with embryonic mortality in Japanese Black cattle.BMC Genomics 17: 968
- Paul RC, Okuda Y, Nguyen TB, Le TNA, Ibi T, Kawamoto Y, Nozawa K, Kunieda T.（2019）.Genotype distribution and allele frequencies of the genes associated with reproductive traits and hereditary disorders in Japanese native horses. J. Anim Genet. 47, 29-36.
- S. Sasaki T. Ibi.(2021). A genome‐wide association study reveals a quantitative trait locus for calf mortality on chromosome 9 in Japanese Black cattle. Animal GeneticsVolume 52, Issue 2 p. 214-216