RALEIGH, N.C. — N.C. State University is used to getting weird gifts. In 1987 someone donated 400 pairs of odd socks. Another time someone gave $100,000 worth of bugs. This year’s haul contains a gift that will keep on giving: $20,000 worth of bull semen.

Henry Black, a retired dairy farmer from Baldwin, Maine, figured that the university was the best repository for his gift — enough units of prime Jersey bull semen to impregnate 3,000 cows. He knew philanthropist William Kenan donated an entire herd of Jersey cattle to NCSU back in 1966.

“He was a family friend of my grandfather, and that figured in my decision,” said Black, whose Briarcliff Farm in Cumberland County has a reputation for fine Jerseys. “It just wouldn’t have been appreciated up here in Maine.”

So early this spring, Black loaded three heavy, barrel-like containers onto a Greyhound bus and paid the $300 fare to send the semen to Raleigh. Inside the steel containers, plastic straws filled with frozen bull semen were kept cold in liquid nitrogen.

In Raleigh, NCSU animal science professor John Wilk picked up the canisters from the bus station downtown.

“It’s a rather surprising and unusual gift,” said Wilk. But he wasn’t complaining.

The sperm will fit right into a goal of NCSU’s dairy research program to improve milk production in the Jersey breed through genetic selection.

The semen donated to NCSU is no ordinary stuff. The samples come from assorted bulls whose mothers or daughters were milk-producing stars. That means the semen should produce future female offspring that will yield lots of milk.

Already, about six high-milk-yielding cows at NCSU’s dairy research station have been impregnated with some of Black’s bull semen. Wilk said researchers hope studying the offspring sired by these bulls will increase understanding of how milk production is inherited.

That knowledge in turn may help researchers and dairy breeders figure out how to produce cows that yield even more milk.

Due to selective breeding of Jerseys for milk production, present-day Jerseys already yield approximately 1,875 gallons of milk per year, an average 375 to 500 gallons more than their ancestors.

Since the 1980s, dairy farmers nationwide have depended upon a handful of top dairy bulls for the frozen semen they need to artificially inseminate their Jerseys.

Currently, for example, only 68 bulls fertilize the majority of the nation’s 150,000 Jersey cows.