(Reuters) - Morgan Stanley (>> Morgan Stanley) lost money more frequently in trading during the second quarter than it did in the previous or year-ago periods.

The investment bank lost money in 15 of the 64 trading days for the quarter ended June 30, or 23 percent of the time, according to a 10-Q filing with the U.S. Securities and Exchange Commission.

That compares with four days of losses, or 6 percent of the trading days, in the March 31 quarter, and eight days of losses, or 13 percent of the trading days for the year-ago period.

The bank's sales and trading net revenue fell 35 percent to $2.25 billion in the second quarter from $3.44 billion in the year-ago period.

Morgan Stanley also said its net exposure to five troubled euro zone nations spiked 73 percent in the second quarter, reiterating an earlier disclosure on July 19.

Morgan Stanley increased its holdings of stocks, bonds and derivatives backed by banks, governments and other counterparties in Greece, Ireland, Italy, Portugal and Spain, while also reducing hedges against the risk that those exposures might turn into losses.

Meanwhile, the investment bank significantly reduced its exposure to France by building up a large short position against the country's sovereign debt.

Morgan Stanley's shift in exposures is notable because the bank's stock and bond prices came under pressure last fall over concerns about its exposure to Europe, particularly France.

The bank began disclosing its exposure to euro zone countries in October in response to the market reaction, and its ongoing disclosure of French exposure is unusual: Even Jefferies Group Inc (>> Jefferies Group, Inc.), which cut its European assets by 75 percent in a matter of days last fall in response to market pressures, did not feel compelled to include France among the countries whose stocks and bond exposures it detailed.

At June 30, the bank had $5.41 billion worth of assets related to those five countries, a 35 percent increase from three months earlier. After factoring in reduced hedges, the bank had $4.18 billion in net exposure to those nations, up 73 percent from its $2.41 billion in exposure at March 31.

Morgan Stanley's euro assets represent 0.7 percent of its $748.52 billion in total assets at June 30, and 7.5 percent of its $71.64 billion in total equity.

Morgan Stanley also significantly reduced its exposure to France, flipping to a net short position against the country's sovereign bonds.

The bank held $2.74 billion in exposure to French stocks, bonds and derivative counterparties as of June 30, less than half of what it had at March 31. After credit default swap hedging, Morgan Stanley had $1.35 billion in exposure to France, down 67 percent from three months ago.

The driver of that change was a $1.95 billion net short position against French sovereign bonds Morgan Stanley held at June 30, compared with a $542 million long exposure on March 31.

Morgan Stanley shares closed at $14.14 on Monday, up 3 percent for the day and down 7 percent the year to date.

(Reporting By Lauren Tara LaCapra; Editing by Steve Orlofsky)

Stocks treated in this article : Jefferies Group, Inc., Morgan Stanley