Sheep Industry News March 2023

Animal Health Committee Discusses Response Strategies for Producers

ESTABLISH A RELATIONSHIP Washington veterinarian Jill Swannack gave her view as a prac titioner, recommending that sheep producers find a veterinarian or two now, and throw some business their way. “Reach out before you need them,” she recommended, to estab lish a client relationship, even scheduling a flock visit before any problems arise. “Get these relationships established now, before there’s an emergency.” Ron Phillips of the Animal Health Institute explained the com plex process for drug development and approval for food animals in the United States. Food animal drug products take much longer to gain approval than those for companion-animals, Phillips said, taking up to a decade and $100 million in costs for a new food animal drug to get to the approval stage. The animal health market has boomed in recent years, rising from $9.9 billion in 2016 to $13.8 billion in 2021, Phillips said, but 63 percent of the product market is companion animals – not food animals – even though there are 400 million companion animals and 10 billion food-producing animals. While drugs for human use are regulated by a single agency – the Food and Drug Administration – animal health product devel opment and approval is subject to review and regulation by three agencies, including the FDA, Environmental Protection Agency and U.S. Department of Agriculture. Animal health drugs must be proven to be both safe and effec tive, which is achieved through a complicated three-stage develop ment process by the companies providing data packets to regula tory agencies. Those data packets must establish that the animal health drug is safe for both humans and the target animals, as well as provide for environmental and product safety. In addition, studies must prove its effectiveness in the target ani mal, Phillips said. Phillips suggested that there needs to be greater global harmonization of regulatory data requirements, since much research and development of these drugs takes place in Europe or Australia, but those results are not accepted by regulatory officials in the United States. It’s also important to maintain existing animal health products on the market, Phillips pointed out, citing the movement of antimi crobials to veterinary prescription only status.

CAT URBIGKIT The Shepherd B

y the time Cache Valley Fever is detected in your flock, it’s generally too late to do anything about it, Dr. Reid Red den of Texas A&M AgriLife told members of the Animal Health Committee meeting in Fort Worth, noting that the virus can be devastating to a lamb crop. “Most of the damage has been done by the time you know there’s a problem,” Redden said. CVF was first detected in the Cache Valley of Utah in the mid 1950s, but has become more widespread. The virus is similar to Blue Tongue and Rift Valley fever and is transmitted by mosquitos. The timing of the infection is a determining factor in the severity of the disease, Redden explained. CVF often appears in a January lambing scenario with the birth of malformed lambs – but the infection occurred weeks before. If the ewe is infected prior to 28 days of pregnancy, it will result in embryonic death. If infection occurs between day 28 and day 35, then the fetus is likely to have severe abnormalities in the central nervous system. If infection occurs between days 35 and 45, the lambs are likely to be born weak, perhaps will less severe malfor mations. Signs of CVF include abortions, dystocia, weak lambs and still births. Dystocia (difficult births) is a major issue in a flock infected with CVF, Redden said, noting it can be very difficult to get the lambs out and in some cases the humane action is to put down the ewe. Congenital defects in the fetal lamb include poor muscle development, twisted backs, rigid legs and shortened jaws, Redden said. Sheep that are most susceptible to CVF are naive sheep such as ewe lambs, Western ewes and sheep grazing in new wetlands. With no treatment or vaccine, prevention during the mosquito season is important, Redden said, such as avoiding wet pastures or delaying breeding until after a hard frost eliminates most of the mosquito threat. Redden’s presentation was one of several important animal health updates to the group, and many sheep producers partici pated in a discussion about a shortage of small ruminant veterinar ians and the challenges that poses as antibiotics are switched to prescription-only availability.

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