Associated Press - June 29, 2009 7:45 PM ET

LINCOLN, Neb. (AP) - Nebraska agriculture officials say the results of the first week of testing for bovine tuberculosis have come back negative.

Some 1,700 head of cattle were tested during the week of June 15-21. An additional 3,300 head of cattle were tested last week. Those results are pending.

State and federal officials are hoping to stem the spread of the disease that was first reported in a herd of beef cattle in north-central Nebraska's Rock County earlier this month.

As of Sunday, 43 herds in 14 north-central and eastern Nebraska counties have been quarantined.

The disease typically spreads from one animal to another through the inhalation of bacteria. Experts say infected animals can transmit the disease to healthy ones within several feet.

On the Net:

Nebraska Department of Agriculture, http://www.agr.ne.gov

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