NEW YORK (CNN/Money) - Treasury prices were mixed Monday, with short and medium-term notes dipping ahead of auctions this week that will put $51 billion in new government debt on the market.

The benchmark 10-year note fell 5/32 of a point to 97-24/32 to yield 4.28 percent, up from 4.26 late Friday.

The five-year note lost 5/32 of a point to 100-2/32, yielding 3.99 percent, and the two-year note fell one tick, yielding 3.76.

The 30-year bond, up 3/32 of a point to 111-7/32 to yield 4.62 percent, down from 4.63, benefited as traders moved money into long range paper. Bond prices and yields move in opposite directions.

"The auctions will be a challenge to sell at current prices," Christopher Rupkey, senior financial economist at BTM, told Reuters.

Rupkey also said bonds could fall further if retail sales numbers, set to be released the morning of a $14 billion sale of ten-year notes, come in strong.

The Treasury is selling $22 billion of three-year notes Tuesday, $15 billion of five-year notes Wednesday and $14 billion of 10-year notes Thursday.

Also weighing on bonds was an employment report released Friday, which showed a gain of 274,000 jobs last month, up from a revised 146,000 gain in March. Economists surveyed by Briefing.com had forecast a 170,000 gain in April.

The hefty gain stoked talk of inflation and eased concerns that an economic slowdown would prompt the Federal Reserve to pause its monetary tightening campaign.

Inflation hurts bonds as it erodes the value of the fixed-income investment. However, rising interest rates generally help the dollar as they make dollar-denominated securities more attractive to foreign investors.

In currency trading, the dollar gained against the yen and hit a three-week high against the euro early Monday.

The euro bought $1.2843, up from $1.2824 late Friday, while the dollar bought ¥105.63, up from ¥104.99 in the previous session.

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