NEW YORK (AP) ¿ Shares of blood analysis systems company Abaxis Inc. fell Tuesday after a SunTrust Robinson Humphrey analyst downgraded the stock, pointing to weak sales of Abaxis' Piccolo xpress testing device. Analyst Jonathan Block said sales of Piccolo systems "dropped precipitously" this year after Abaxis instituted a new sales strategy, and the company will probably need to close some large deals to reach Wall Street's expectations. If that does not happen, the stock price could drop, he said. Block cut his rating on shares of the Union City, Calif., company to "Neutral" from "Buy," and trimmed his fiscal 2010 and 2011 profit estimates. He now expects the company to earn 70 cents per share for the year ending in March, down from 71 cents per share, and 90 cents per share the following year, down from 92 cents per share. On average, Thomson Reuters says analysts expect 71 cents per share in 2010 and 89 cents per share in 2011. In morning trading, Abaxis stock slid $1.18, or 4.6 percent, to $24.41. Block said Abaxis' new veterinary products are selling well, and so are its chemistry analyzer products. However he said the stock price will not rise further until sales of the medical products improve. Abaxis shares have climbed 62 percent over the last year, and peaked at $29.80 on Sept. 17.