Andrew Feltus, whose Pioneer Global High Yield Fund ranks second in its peer group this year, calls bonds of Cia. de Bebidas das Americas, Latin America's largest brewer, the "all-time best investment I've made."

The Brazilian beer company, known as AmBev, has generated a total return of more than 40 percent in less than two years.

"That company has made more money for our investors than any other," Feltus, 35, said in an interview at his office at Pioneer Investment Management Inc. in Boston. His other holdings include high-yield, high-risk bonds from Norwegian oil-services company Aker Kvaerner ASA and Russian energy provider OAO Gazprom.

Feltus's $155 million mutual fund invests in junk bonds in countries from the United States to Brazil to Russia. He spreads his risks, leading to a 7.9 percent return this year. Only the MainStay Global High Income Fund is performing better among 23 global debt funds tracked by Bloomberg. The MainStay fund is up 8.5 percent.

The MainStay fund has about four-fifths of its assets in debt sold by developing nations. Feltus's fund had 53 percent of its assets in U.S.-based bonds at the end of September; 17 percent in developed nations in Europe and Asia; and 30 percent in emerging markets such as Russia and Brazil. The developing-country bonds include both corporate and government-issued securities.

Bonds of lower-rated borrowers pay higher yields to compensate investors for the increased risk that the companies won't pay their debts. This year U.S. junk bonds returned 6.8 percent to investors, compared with 4.3 percent for investment-grade corporate debt and the 3.2 percent gain of Merrill Lynch & Co.'s U.S. Treasury and agency bond index. The Standard & Poor's 500-stock index is up 1.5 percent, including reinvested dividends.

Feltus, who graduated from Tufts University outside Boston and joined Pioneer a decade ago, makes investment decisions based on what he views as the countries and currencies with the most promise. He selects what to buy after a review with a team of credit analysts led by Michael Temple, 44.

Feltus plans to reduce his holdings to 50 to 70 securities from 100.

"Every high-yield company has something wrong," he said. "There's a reason they get a high yield. It could be a bad business, it could be a bad balance sheet." Some suffer from a "Zip code problem," meaning they're healthy companies that are valued at less than what they're worth because they're located in countries with political or economic problems, he said.

Emerging-market debt adds "spice in the form of higher-yielding securities to offset the stability of U.S. debt securities," said Brad Durham, managing director of EmergingPortfolio.com Fund Research in Cambridge, Mass.

Feltus said he was drawn to Sao Paulo-based AmBev because of its two-thirds market-share positions in Brazil and Argentina, South America's biggest economies, and a management team led by chief executive Carlos Brito. Belgium's Interbrew SA is buying AmBev to become the world's second-biggest brewer after Anheuser-Busch Cos. of St. Louis.

Feltus acquired AmBev bonds when they were trading as low as 74 cents on the dollar and had a yield of more than 16 percent. "For a high-yield investor, that's nirvana," Feltus said.

AmBev probably will be raised to investment-grade status by credit-rating companies, Feltus said. He has sold virtually all of the bonds because they have "pretty much run their course" and other Brazilian issuers offer higher yields.

Feltus owns bonds of Cia. Siderurgica Nacional, Latin America's third-largest steelmaker, and Cia. Vale do Rio Doce, the world's biggest producer of iron ore.

The Pioneer fund's largest holding is Aker Kvaerner, a builder of oil, gas and other industrial facilities. The Lysaker, Norway, company was formed in the 1990s through a series of mergers. At first, the pieces didn't fit, Temple said. The company then initiated restructuring steps, including the spinoff of a shipbuilding business.

Aker Kvaerner is benefiting this year from record oil prices and an increase in demand for processing equipment for the mining, chemical and paper industries.

Pioneer started buying Aker Kvaerner zero-coupon bonds, which don't pay annual interest, for the equivalent of 40 cents on the dollar 18 months ago, Temple said. The bonds now trade at about 72 cents. At the end of last month, Aker Kvaerner accounted for 3 percent of the Pioneer fund.

The fund enhanced its return by buying bonds issued in Norwegian kroner rather than the more-expensive dollar-denominated securities, Feltus said. The fund has 14 percent of its assets in non-U.S. currencies, he said.

Feltus's fund is sold through brokers and financial advisers, who charge an upfront sales fee equal to 4.5 percent of assets invested. In addition, the fund charges $7.50 for each $1,000 invested, compared with an average of $10.60 for similar funds, according to data compiled by Bloomberg.