動物的品種不同,其特徵亦會有所不同。以狗為例的話,金毛尋羊犬以及臘腸狗就是非常鮮明的例證。488Please respect copyright.PENANAHqCiLHCDAn488Please respect copyright.PENANAe9ykSbhKaG
488Please respect copyright.PENANAF7bk76rgkT
至於牛隻,農場飼養用的大致分為兩種,主力出產牛奶的乳牛(Dairy Cattle)和主力屠宰成肉類出售的肉用牛(Beef Cattle)。488Please respect copyright.PENANAZBS29NWGV3
488Please respect copyright.PENANAaWMjW5audH
各舉一例的話,前者品種例子為Holstein(荷斯坦),而後者則為較為廣泛認識的Angus(安格斯)。488Please respect copyright.PENANACsSpcm0kwc
488Please respect copyright.PENANA89O8Qig33f
牛天生會否長角,將視乎品種而定。大多數的乳牛品種天生均長有角,而食用牛多數的品種則天生無角。488Please respect copyright.PENANANyeFkdl1XL
488Please respect copyright.PENANAZvEQBFacr3
這裡讓農夫感到煩惱的是,乳牛隻會利用頭上的角互相攻擊對方甚至自己。488Please respect copyright.PENANAdwLSrywbVB
因此慣常的做法會麻醉牛隻然後再進行除角手術,以免牛隻受傷因而損失獲利,但這做法引起動物權益成員的關注及爭議,認為此舉會對牛隻帶來創傷。488Please respect copyright.PENANAFCBwO4ut1m
488Please respect copyright.PENANA08aMGgeNv1
(圖2)最為有效率及一勞永逸的解決辦法,自當然就是培育沒有長角的品種,一直傳遞下去。488Please respect copyright.PENANAUy75lWexqa
有科學家致力尋求發現,發現牛隻基因染色體1的某一段位置的重覆區域,將會導致乳牛品種不會長出牛角。488Please respect copyright.PENANAYE5A6EunbG488Please respect copyright.PENANATweXh6Emlz
488Please respect copyright.PENANAz3mOYOHlS8
(圖3)因此,他們嘗試抽取長角品種的皮膚細胞,利用CRISPR基因編輯技術在那段基因區域上加添重覆區域(Ref1),再經過一系列的工序,將已編輯的細胞人工培植到牛隻身上,觀察誕下的胎兒會否長出牛角。488Please respect copyright.PENANAC6HNplBiub488Please respect copyright.PENANAUHFX9HFFou
488Please respect copyright.PENANAR5fcayCcmi
(圖4)最終所誕下的牛隻的而且確沒有長角,但因器官衰竭等問題很快便與世長辭。488Please respect copyright.PENANAQPHbq15SSN488Please respect copyright.PENANANLLSk1C30x
488Please respect copyright.PENANAIXlYkjhmB0
488Please respect copyright.PENANAG2ByOKeEHO
這研究確實了CRISPR技術在牛隻的應用,但顯然仍有一系列的應用問題需要改善。在這實驗中,6隻人工培植受孕的牛隻中,只有一隻成功誕下嬰兒。488Please respect copyright.PENANAFngXn7oZei
488Please respect copyright.PENANAFngv2vaQHG
至於為何不重點培育沒有長角品種的乳牛,原因是牠的產奶量較其他有角品種的最少。488Please respect copyright.PENANAeq9Il6a55e
488Please respect copyright.PENANA1cNsXXhAtH
農父及科學家的最終目標,當然就是希望培植沒有長角而產奶量豐盛的牛隻。但這做法是否符合動物權益,這又會是一場永無休止的辯論。488Please respect copyright.PENANA7WBdPvREDy
488Please respect copyright.PENANAsewAc5skTq
488Please respect copyright.PENANAQ0IU3Yl2pj
如果想我快啲出文的話,請入去Penana網站科普專欄–薯不揀單俾一個like以及Bookmark,這對我非常之重要。488Please respect copyright.PENANAnwUWrboTx5
488Please respect copyright.PENANAbbl7sUfcDu
Link: https://www.penana.com/story/66244/%E7%A7%91%E6%99%AE%E5%B0%88%E6%AC%84-%E8%96%AF%E4%B8%8D%E6%8F%80%E5%96%AE/toc488Please respect copyright.PENANAZ4OfAQBUj4
488Please respect copyright.PENANAk21lcdUVVU
同時亦可以在Penana網站裡按「買一嚿/半嚿薯仔」,以課金的方式推動我繼續搜羅資料寫文,多謝。488Please respect copyright.PENANAW0Sjd7be8p
488Please respect copyright.PENANAwMzrkm6huR
Link:488Please respect copyright.PENANAum3XThHEeZ
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio488Please respect copyright.PENANAYB4FTcBxTr
488Please respect copyright.PENANAo9TFgS4g5l
488Please respect copyright.PENANACPAJHT543z
有興趣接收科學資訊的話,歡迎follow IG: potatopigtongue。488Please respect copyright.PENANA3I456taZsv
488Please respect copyright.PENANAK1LBM2Rc0W
Ref1:https://www.nature.com/articles/s41598-020-70531-y488Please respect copyright.PENANAPUAp6pdxRF