By Sherry Bunting, Farmshine, May 3, 2024
WASHINGTON – The recent USDA federal order requiring testing before transport of any lactating dairy cow from any state to any other state, effective April 29, took many in the industry by surprise after it appeared there was a lull in new cases of highly pathogenic avian influenza (HPAI) in dairy herds. Some wonder why, given the fact that cattle recover and the one and only human case in a dairy worker was a mild conjunctivitis that resolved on its own.
Stemming the spread is important, officials say, because of potential transmission from dairy cows to poultry, since it is lethal in poultry. Additionally, they explain that researchers need to understand what is an evolving in this novel situation blamed for a syndrome that began in Texas in February marked primarily by reduced feed intake, marked drop in herd level milk production, thick or colostrum-like milk in affected cows, and dry tacky manure.
On April 25, USDA Animal and Plant Health Inspection Service (APHIS) updated the number of herds with HPAI detections to 36 in 9 states: Texas (12), New Mexico (8), Michigan (6), Kansas (4), Idaho (2), Ohio (1), North Carolina (1), South Dakota (1), and Colorado (1).
The federal order includes mandatory reporting of HPAI, and the required pre-movement testing pertains only to lactating dairy cows.
Pennsylvania State Veterinarian Alex Hamberg says the next few weeks will tell us if H5N1 is more widespread in dairies via the federal surveillance now underway through the pre-movement testing of all lactating dairy cows crossing borders from any state to any other state.
The only exception is for interstate shipment of cows directly from the farm to a federally-inspected slaughter plant.
Any lactating cows shipped across state lines to an auction (even a slaughter-only auction) at a sale barn must have official identification, a certified veterinary inspection (CVI) and an HPAI-negative milk sample test from a qualified lab within 7 days of transport.
Lactating dairy cows can move to sale barns within the same state, with just owner/shipper statement and back tags. After the sale, they are permitted to go from the sale barn to an out of state federally-inspected slaughter plant if they proceed there directly without any stops to unload any commingled animals from that trailer to a non-slaughter premises.
Farmers and cattle dealers have questions about what is needed to ship cull dairy cows to livestock auctions, where packer buyers come from several states.
Hamberg gave examples.
“If you are going to a sale barn within your state, you don’t need the extra testing, but this would limit the sale to buyers within your state – unless that buyer takes the animal(s) directly from the auction, to slaughter,” he said.
“Dairy cows (from Pennsylvania dairy farms) can go to a sale barn in Pennsylvania, and then go across state lines to a slaughter plant in New Jersey with just an owner-shipper statement and back tags — as long as they leave as a group, get on the trailer as a group, and don’t get off that trailer until they are at an FSIS inspected slaughter plant.”
During the call Hamberg noted that Pennsylvania raised its testing age for non-lactating dairy cattle from 12 months to 18 months via nasal swab. These animals require testing only when coming into Pennsylvania from states that have had an HPAI detection.
Lactating dairy cow testing is only through milk samples. These milk samples must be collected by a licensed veterinarian or a designee at the farm, if the veterinarian is comfortable signing for that sample via a valid client-patient relationship (VCPR).
USDA APHIS will pay for the cost of all pre-movement and suspected illness testing for HPAI H5N1, but the costs of taking the samples and sending them to a qualified lab are not covered.
Both Hamberg and Jeff Warner,director of the Pennsylvania Department of Agriculture Bureau of Food Safety and Laboratory Services,emphasized the effectiveness of pasteurization to inactivate the virus in milk. Hamberg noted that PCR testing has a tendency to pick up dead strands of virus so that can be confusing, but pasteurized milk is safe.
Warner said there is no ban on raw milk sales from permitted farms at this time because there have been no HPAI detections in Pennsylvania; however, all permit holders have been notified by mail and email to be mindful of the signs of HPAI, and as all dairy farms are expected to do with any sick cow, withdraw that milk from sale.
“We have no cases in Pennsylvania to-date. We have done some testing, and so far, no detections. Let’s keep that trend going,” said Hamberg.
Producers asked: What happens when there is a positive test?
“If a test comes back positive,” said Dr. Ernest Hovingh, Penn State extension veterinarian andresident director of the Penn State Animal Diagnostic Laboratory System (PADLS),“we notify the national veterinary lab system and the state department of agriculture, and then Alex (the state vet) springs into action.”
“Our quarantine response says cattle can’t leave the farm without permission, but if cattle need to go to slaughter or somewhere else, we would do a risk assessment for permitting,” said Hamberg.
“We also would use 30-day increment permits for milk movement to processing, so you could move milk from this point to this processor, but while doing it, you follow these biosecurity rules like being the last stop on the truck and having additional cleaning for trucks leaving the farm, and having enhanced biosecurity plans in place,” he explained.
Hamberg has much experience with quarantine response for HPAI in Pennsylvania’s poultry industry, which this year surpassed dairy for the first time as the largest cash receipts ag sector in the Commonwealth. He noted the risk of spread from dairy cows to poultry is a big concern, since HPAI is deadly to poultry.
At the same time, he said, “we are seeing nationally a 20% drop in herd level milk production (in dairy herds where HPAI has been detected). That hurts. Dairy is tough enough, and losing 20% of your milk, that stinks, so we don’t want to compound that loss. We want to move milk in a safe way to get your milk to processing” — if HPAI is detected on a Pennsylvania dairy farm.
“This is not a big scary thing. We have steps we can do — even if we get a positive case,” said Hamberg.
Hovingh noted that having Pennsylvania dairy heifers raised out west is now a high-risk practice.“Your animals would be going west to a potentially infected state, and they would return at over (18 months of age) and be subject to state rules for testing” — if they come back from a state with HPAI detections.
USDA’s final rule on mandatory electronic identification was published in the May 1 Federal Register, Hamberg noted. In 180 days, the rule requires E-ID for all sexually intact cattle over 18 months of age, as well as bison and all cattle in exhibition (show) and rodeo.
With the HPAI pre-movement testing for interstate movement of lactating dairy cows and the mandatory E-ID at the same time, crossing state lines for shows and sales now requires additional documentation.
According to Dr. Hovingh, the state PADLS system promises a 3-day turnaround on pre-movement testing, which has to be done within 7 days of interstate transport. “But we think we can do same day turnaround, depending on volumes submitted.”
He urged producers planning herd dispersal sales to give a heads up as they prepare to “get their ducks in a row” so cattle can move on to buyers from other states on sale day.
Hovingh said now is the time for Pennsylvania dairy farmers to get their biosecurity plans in place, so they have that box checked in the event of an HPAI detection and quarantine in the state. Approved biosecurity plans would be required for those 30-day milk movement permits that are part of the state’s response.
It’s also important for farmers suspecting HPAI, to report it.“We’ll come out and test,” said Hamberg. “Our concern is that if cattle transmit it to poultry, those flocks are depopulatedand controlareas are set up. Following through is essential for both our dairy and poultry industries.”
Hovingh said species segregation is important on farms with both dairy cows and poultry, and biosecurity is essential for personnel tending both. The new twist is clean clothes and a shower go beyond clean boots to keep from exposing poultry to any raw milk on clothing, hands, etc.
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