Carlyle Plain Raised Bridle with Laced Reins
$105.00
| |
|
Devastating Loss of Foals in Kentucky
|
Most everyone has heard at least bits and pieces regarding the recent devastating loss of foals in Kentucky. Labelled as Mare Reproductive Loss Syndrome (MRLS), scientists have been feverishly working to identify the causal agent that has left 529 foals dead, approximately 6% of this year’s foal crop gone, and an estimated 25% of next year’s lost. Based on the latest reports from Kentucky, the leading theory attributes the eastern tent caterpillar as the likely source for the multitude of late-term abortions, stillborn foals or sickly foals, and early fetal losses (EFL).
Scientists of the University of Kentucky Gluck Equine Research Center were first made aware of the problem around the end of April and the beginning of May, with numerous reports the weekend of the Kentucky Derby. Within the first two weeks of May, an increasing number of reports began coming in from different farms in Kentucky regarding their own losses. Farm managers were finding multiple late-term aborted foals in the pastures or discovering that mares that were pregnant during an ultrasound at approximately 40 days were no longer pregnant during additional ultrasounds at 45 to 80 days. Also, during these subsequent ultrasounds, the fluid around the fetus was cloudy and abnormal. Usually, this observation was followed by the foal’s death and expulsion. The placentas associated with MRLS were thick and swollen, “consistent with red bag syndrome.”
In addition to the MRLS and EFL, breeding farms in Kentucky have reported an increase in eye problems, as well as a rise in cases of pericarditis. Unfortunately, researchers have not been able to determine a direct link between the late-term abortions and early fetal losses, and these other diagnoses.
Many farm managers and horse owners have tried to thwart the mysterious agent by giving feed supplements, such as MareGuard or Myco-Guard, to the mares. These products are intended to bind to the mycotoxins and prevent “them from entering the intestine or uterus by absorbing them ‘like a sponge.’” Although many of the breeders feel these products have assisted in preventing some of the abortions, others, including veterinarians, are not sure of their true effects.
Curiously, in 1980 and 1981, Kentucky breeding farms suffered a high number of abortions and losses of foals. Though the numbers were not as great as those experienced this year, they were still high enough to raise concern. Moreover, the cause for those losses was never identified. One distinct similarity between that period and this one has been the weather patterns - below normal temperatures in March, above normal temperatures in early April, followed by a hard freeze around the third week of April, and drought-like conditions. Scientists believe that all of these conditions potentially could have contributed to the production of some type of toxin.
Scientists, veterinarians, and even the farm managers have held to this theory that there is some toxin prevalent in the pastures, and early attention turned to the notion of endophyte fungus-infected fescue. They also have been studying mycotoxins, phylo-estrogens, and other substances that may be found in the pasture. Initial tests conducted on the pasture grasses, however, have been negative for any suspected mycotoxins. These findings, as well as several other commonalities among the farms, have led researchers to direct their attentions to the eastern tent caterpillar.
The eastern tent caterpillar feeds on wild cherry tree leaves, which can produce cyanide or a cyanide-like substance in the caterpillar's stomach. In the UK College of Agriculture's briefing of May 22, researchers note that "[v]isual correlations on several farms that have experienced MRLS show the presence of wild cherry trees in or near fields where affected mares were grazing." Though initial tests on the caterpillars were negative for cyanide, later tests have indicated high levels of zearalonene - an estrogenic mycotoxin shown to cause reproductive, cardiac, and eye problems - in the caterpillar's feces. Although uncertain of the direct link between the caterpillars and the horses, scientists suspect that the mares ingest the fecal matter that is dropped on the pasture grasses near the wild cherry trees. These caterpillars, along with the feces, also could be present in the hay produced from farms with wild cherry trees that grow near the fields. According to reports, there has been a very high number of eastern tent caterpillars in Kentucky this year, as well in 2000, which mimics the infestation in 1979 and 1980, and to a lesser extent, in 1981 - the same years Kentucky breeders witnessed a significant increase in aborted foals. Scientists hypothesize that these caterpillars may be linked to that event, as well.
Despite these dramatic coincidences and significant pieces of evidence which make this the leading theory, many scientists believe that there has not been sufficient proof to identify the eastern tent caterpillar as the definitive causal agent. According to the briefing of May 25 by the University of Kentucky College of Agriculture, scientists emphasize that “the current observations are preliminary, must be confirmed, and that further validation is absolutely essential. We have not yet met reasonable standards of scientific proof.” Unfortunately, the suspected agent is no longer available for examination and testing, since sightings of the eastern tent caterpillar moth were made as early as May 22. In an effort to gather as much information as possible, the UK College of Agriculture is conducting a survey among the many breeding farms in Kentucky with the hopes of gleaning data that will give them more answers to the puzzle. Scientists are also continuing to study the tissues from the aborted or stillborn foals as they examine other possibilities which include mycotoxins, fungal endophytes, chemical agents, and even the recently offered suggestion of hemlock.
In the meantime, the number of stillborn or aborted foals has declined, with the last one, to date, being submitted on May 22. Given this, University of Kentucky Extension Specialists for Pastures and Forages, Dr. Jimmy Henning and Dr. Garry Lacefield, feel that it should be safe to turn horses back out to pasture, but offer the following recommendations to horse breeders who have been or could be affected by the MRLS.- “Mow pastures to dislodge any larvae or caterpillar excrement from the leaves.”
- “Do not confine horses in small areas that are surrounded by wild cherry trees.”
- “Using temporary fencing to skirt off fence line areas next to high numbers of wild cherry trees may provide an extra level of safety.”
They do recommend that since it is possible that the eastern tent caterpillar could be present in “first cutting hay,” – specifically that which may have been near wild cherry trees - these bales should be removed from the fields. Also, hay fields that are “surrounded by cherry trees should be scouted for the presence of larvae or cocoons prior to cutting.” They do note, however, that “future cuttings from these fields are considered safe” since the caterpillars are no longer present.
Impact
Though the Thoroughbred has been hardest hit by this event, especially when one considers its dominance in Kentucky, it has not been the only breed. Others that have been affected include, but are not limited to, the Arabian, Quarter Horse, Standardbred, Paso Fino, Paint, Tennessee Walking Horse, Rocky Mountain Horse, Appaloosa, and Morgan. It has also been witnessed in some Warmbloods, ponies, and miniatures. Though to a much lesser extent, reports have also filtered in from other states, including Ohio, West Virginia, Pennsylvania, and Maryland.
Sadly, a considerable amount of damage has been done to the horse industry, not just emotional, but also financial. With the losses that have been experienced, the costs are estimated at over $200 million as one out of twenty of the expected 10,000 foals for this year's crop have died and, as noted at the beginning, almost a quarter of the 2002 foal crop has been lost. Since current law prevents the US Department of Agriculture from providing financial assistance, Kentucky Senators Jim Bunning and Mitch McConnell have made efforts to introduce legislature that will provide aid to those breeders hardest hit by this event.
MDhorse.com will continue to provide updates as they become available.
|
|
|
|
|
|
|
