TAYLORSVILLE, Miss. (AP) — Despite higher milk prices, hot temperatures and production costs are making it harder for Mississippi dairy farmers to turn a profit.

Milk prices hit a record last month in the United States, where consumers paid an average $3.80 a gallon, compared to $3.29 in January, according to the U.S. Department of Agriculture. It forecasts prices will remain high throughout the year.

Prices are likely to remain high worldwide until dairy farmers add more cows or shift production to powders, which are more easily traded than the liquid stuff.

International dairy product prices increased 46 percent between November 2006 and April 2007, with milk powder prices increasing even faster, according to the U.N. Food and Agriculture Organization.

Lamar Adams, the Walthall County director with the Mississippi State University Extension Service, said with extremely hot temperatures, milk production will decrease from the stressed cattle and dairy producers will have less milk available to take advantage of those record prices.

Adams said scattered rains in July helped farmers produce acceptable amounts of corn and hay used as feed for dairy cows.

‘‘Milk production has taken a nosedive because of heat stress on the cattle,’’ he said.

Adams said most dairy cattle in Mississippi are Holsteins, which are large-framed cattle, which start stressing when temperatures go over 70, but especially when daytime temperatures are over 90 degrees and nights are warm.

Adams said the cows first instinct is to stop eating when they get hot, and that results in decreased milk production.

In south Mississippi, Hurricane Katrina in 2005 took out many of the shade trees in pastures. Some farmers erected man-made shade structures to help. The few trees that remain may suffer and eventually die from the concentration of cattle underneath them.

Production costs continue to rise.

Farm economist Bill Herndon said feed, fuel and fertilizer costs have increased substantially in recent years. Mississippi producers still find themselves in need of assistance to continue in the business, Herndon said.

There is some help available.

The Legislature this year approved a no-interest loan program to assist qualified dairy producers with up to $20,000 for milk transportation costs.

The application process, overseen by Mississippi State, began on July 1 and will continue through May 2009.

The loan application requires proof that the farm produced in a calendar year 300,000 pounds of milk, which is the amount of milk produced by about 20 cows.

Herndon said farmers must provide evidence of the amount of milk shipped from the farm and the amount charged to their farm for shipping to a processing plant. Both figures are listed on monthly milk checks. This information can come from records between January 2006 and May 2009.

‘‘We know it is a busy time of year as producers work their cattle and put up feed for the winter, but we need to get applications in as soon as possible, Herndon said.

The maximum amount that can be paid out is $3.5 million.

As of Aug. 10, Herndon said dairy farmers have applied for about $500,000 under this no-interest loan program. He said farmers will need to request about twice that amount before bonds can be sold and money made available to farmers.