• Cryptocurrency and blockchain-related firms slide in premarket trading

• Bitcoin , the world's biggest cryptocurrency, slides 3.15% to $81,974.01 after climbing for three straight sessions

• Ether down 3.33% at $2,408.48

• Crypto exchange Coinbase Global declines 3.8%

• Crypto miners: Riot Platforms Inc , MARA Holdings , Hut 8 and Bit Digital down 3% to 5%

• BTC buyer Strategy slides 5.4%, among the biggest decliners

• BTC mining machine maker Canaan Inc down 3.4%

• ProShares Bitcoin Strategy ETF loses 3.2%

• iShares Bitcoin Trust ETF down 3.1%

• Bitcoin remains down over 6% YTD, while ether has fallen roughly 19.2%

(Reporting by Jayasree Prabhu)