by Elizabeth A. Tomlin
At recent dairy resiliency workshops held by CCE CNY Dairy & Field Crop specialists and PRO-Dairy, Dr. Roger G. Ellis, DVM, of the NYS Department of Agriculture and Markets, presented updated information on a multi-drug resistant disease emerging in Northeast cattle.
“Salmonella Dublin is most commonly seen as a severe respiratory disease in calves,” Ellis reported. “This is in contrast to most Salmonella that cause gastro-intestinal disease.”
Salmonella Dublin has recently been recognized in the Northeast and the Animal Health Diagnostic Center at Cornell University has seen several farms with high rates of illness and death in the Northeastern states, including New York.
“This has mainly been out in Western New York, mainly been associated in situations where calves are co-mingled,” Ellis said. “They look like a viral pneumonia and you’ve got high death loss in calves.”
It is reported that the disease rapidly kills calves within a few days of showing signs of illness and on newly infected farms, has killed all calves in specific groups. Ellis reported on a veal operation that had lost 50 to 60 calves. “It was devastating.”
Although the disease primarily strikes young stock from one week to 6 months old, Ellis stated that even though adult cows may not show signs of illness, they can be carriers, harboring dormant bacteria and repeatedly infecting entire herds — especially when they are placed under stressful conditions, which causes the bacteria to emerge and shed by the carrier in their manure and milk. The stress may result from poor management, overcrowded conditions, poor diet, poor air quality, poor hygiene, transportation, or be caused by a co-existing infection.
Outbreaks may cause septicemia, fever, abortions, coughing, labored breathing and diarrhea. Pneumonia resulting in an unusual number of deaths in herds should be investigated promptly for this disease. Illnesses resulting from Salmonella Dublin can be extremely difficult to treat and may be fatal. Once contaminated, it is difficult to clean the bacteria from the housing and environment.
The disease, which is not species specific, poses serious threat to people, companion animals and other livestock if exposed, causing severe illness and possible death.
Animal caretakers showing symptoms of fever, delirium, vomiting or diarrhea should notify a physician. Young children, the elderly, and pregnant women are the most susceptible, as are people with suppressed or weakened immune systems.
As the bacteria are shed in raw milk, it is advisable to only drink pasteurized milk.
“The key to it is you don’t want to get it!” Ellis recommends using a new bulk tank test to detect if there are any “carriers” on your farm.
“There is a test, which can be used on bulk milk from farms to determine if carriers are present in the herd,” said Ellis. “You should consider testing your herd and be sure that cattle and herds where you obtain cattle are negative.”
Tests should be done 3 months apart, 4 times a year, to establish that your farm does not have a carrier. “One sample is not enough! We need to do successive samples to be sure it is not present.”
He advises contacting your herd veterinarian or the Animal Health Diagnostic Center at Cornell University’s College of Veterinary Medicine for more information on this test.
Ellis advises herd managers to take preventative measures through surveillance on the farm and screening of any new animal brought onto the farm before they arrive.
Biosecurity practices are strongly recommended. This includes isolation of all cattle — whether returning to the farm or newly added, avoiding contact with manure at other farms and not wearing the same boots or clothes at any other facility that you wear at your own farm.
Control the spread of the disease by isolating sick calves, improving hygiene, pasteurizing milk and using better cattle movement management. Disinfect and re-bed cattle trailers after use.
More information may be found at the New York State Cattle Health Assurance Program website: http://nyschap.vet.cornell.edu or contact program coordinator Melanie Hemenway at 585-313-7541.
Ellis said that many people are not aware of Salmonella Dublin being in New York State. “We’re trying to do an educational thing to make everybody aware of it so that we hopefully can prevent it, be ahead of it and not get a lot more of it.”
Dr. Roger Ellis, a co-founder of ‘Veterinarians Without Borders,’ has over 30 years of international service experience. He works to improve livestock reproductive health and prevent diseases. He advises contacting your herd veterinarian for more information on this emerging, infectious disease.
by Elizabeth A. Tomlin