Sam Houston Race Park has issued a policy on equine herpesvirus that goes into effect March 6 and will be in place until further notice, according to a memo issued by the track Monday. This policy has been developed in collaboration with the Oklahoma Horse Racing Commission in order to safeguard the welfare of horses participating at Oklahoma racetracks. Skin biopsies were harvested from 16 foals within 24 h of birth and fibroblast cultures were established, expanded and cryopreserved. Vet. 189 Description RHINOMUNE� is prepared by growing an attenuated strain of EHV-1 on an equine cell line and is packaged in freeze-dried form. Gluck Equine Research Center. Any individual that is found to be responsible for a horse entering the enclosure of a racetrack that does not conform to these conditions will be ejected from the grounds and will not be allowed to participate in the race meeting.
Bosh examined the influence of farm management and veterinary practices on reproductive efficiency. Cattle infected during pregnancy may abort. The specific immunizations needed by a particular horse or horses depend upon several factors: environment, age, use, exposure risk, geographic location, and general management. Our data suggest that IgG isotype responses to EHV-1 are more diverse under field conditions than is revealed by experimental studies and that the current modified-live virus (MLV) vaccine induces a more restricted IgG isotype response than does natural exposure to EHV-1. On average, mares fail to produce a live foal in two out of seven years. Additionally, the virus load of nasal shedding and viremia were reduced by vaccination. Only 31% of mares experienced no drift, i.e., foaling on the same day or earlier in the subsequent year.
These observations suggest a more aggressive approach to breeding maiden, barren, and early foaling mares at the beginning of the season, including judicious breeding on foal heat, would have a beneficial impact on reproductive performance. None of the licensed vaccines are labelled to protect against the neurological form of the disease (13). Eastern/Western Equine Encephalomyelitis- These diseases are caused by closely related viruses that survive in the wild bird population and then are transmitted to other animals via mosquitoes. Of increasing impact on performance as it applies to Kentucky is the trend toward increasing book size (the number of mares covered by a stallion during the breeding season). Figures published by the Jockey Club indicate the average book size for Kentucky stallions in 1995 was 35, whereas in 2005 it had risen to 58—compared to a national average of 17. These early vaccines worked on simple principles. Breeding costs comprising veterinary and vanning charges represent a very small percentage of the overall annual cost, which includes the stud fee, maintenance of the mare, and annual mare capital cost (depreciation).
Yet it is the breeding cost that has the greatest impact on reproductive performance. VP2 is the principal serotype specific antigen of AHSV, and the majority of neutralising epitopes are located on VP2 –. Neibergs. Ab4 ΔORF1/2 infected ponies showed significantly shortened primary fevers, and reduced nasal viral shedding, despite the fact that both viruses show similar in vitro growth kinetics. Timing – strictly speaking, timing is a factor of immunity rather than the vaccine itself. Finally, if your horse is exceptionally sensitive, ask your vet whether it would be advisable to administer a dose of a non-steroidal anti-inflammatory medication such as flunixin meglumine (Banamine?) prior to vaccination to minimize side effects. Identical aa residues are bolded.
However, each of these EHV-1 gene products is capable of eliciting both B- and T-cell responses; thus, the role of distinct immune functions conferring protection is not clearly defined. Respiratory disease due to EHV was widely diagnosed among several breeds of horses throughout France and three cases of Coital Exanthema (EHV-3) were diagnosed in the United Kingdom among non-Thoroughbreds. The outbreaks of Equine Infectious Anemia (EIA) reported from Italy and Ireland in June continue to be investigated and further cases have been diagnosed. The origin in both countries is considered to be the administration of an infected equine biological product. R., Meyer, A. 41-46. West Nile Virus (WNV) infection was diagnosed for the first time in Argentina during February and March.
(B) Enlarged section of the analyzed part of the US genome region of wild-type virus (ILTV-A489) and of a gJ rescue mutant (ILTV-gJR) with relevant restriction sites. In the United States equine cases of WNV were reported by the end of June from Iowa, North Dakota, Wisconsin, and Wyoming with human cases reported in California, Mississippi, and Texas. Strangles is a respiratory disease caused by an abscess forming bacteria, Streptococcus equi. EP is considered to be a foreign animal disease in the U.S., but it occurs�in many other areas of the world. A: For young horses under the age of 5, it is recommended they have dental check-ups twice a year. Preventive measures can then be immediately implemented to restrict the spread of infection and mitigate serious disease and economic losses. Accepting that EVA has now become established within the Quarter Horse population, it will be necessary to introduce a preventive program of vaccination accompanied by appropriate monitoring to determine the extent of this infection within the population.
States with more persistent mosquito populations may require more aggressive vaccinations along with aggressive mosquito control techniques. The immunity generated in horses after vaccination is relatively short lived so unless a horse is constantly challenged its immunity wanes and it can be reinfected quite quickly. Administer the third dose at 10 to 12 months of age. The center made the recommendation, which was accepted, that shipment of semen from stallions on the farm be halted. On June 23 results revealed very high antibody titers to equine arteritis virus in the majority of the sera, and by June 26 the virus had been isolated from the semen of two stallions. These findings provided very strong circumstantial evidence of recent exposure to the virus, which was later confirmed by examination of paired sera from individual animals. The owner promptly informed clients that had recently received semen from the infected stallions as well as those who had moved the many donor and recipient mares on and off the farm.
Any animal can carry rabies, however, bats can live the longest with the disease before succumbing to its effects so they serve as the source of spread, especially here in Missouri with its multitude of caverns and caves and bat population. Following extensive communication and submission of numerous samples to the Gluck Center by farms that had recently received semen or mares from the index farm, it was confirmed that equine arteritis virus infection had become widely disseminated to farms both within the state and in six other states. With considerable historical information provided by the index farm, it was determined that infection was most likely introduced in late May, with four stallions becoming infected in early June, three of which began to “shed” virus in their semen. Serological examination of over 200 animals on the farm confirmed an extremely high prevalence of infection, with every mare, foal, and stallion on the farm found seropositive. A third of the yearling colts were also positive, with the yearling fillies being serologically negative. Transfection of each of the equine γ1–γ7 H chain expression vectors into CHO cells stably expressing a compatible mouse λ light (L) chain allowed expression of all seven subclasses. Similar marker vaccines based on gE-deleted PrV have been used to successfully eradicate Aujeszky’s disease from several countries including Germany and the United States (37, 49, 50).
However, the number of pregnant mares losing their pregnancies during early gestation was very high. The initial spread of infection was considered to have been through aerosol transmission from direct contact with animals in the acute stage of infection. This transmission was compounded by the high concentration of animals on the premise. Secondarily, it was thought to be spread by venereal transmission once stallions became semen “shedders” and carriers of equine arteritis virus. Vaccination of non-exposed yearlings using the modified live vaccine ARVAC® (Fort Dodge Animal Health) was undertaken on the farm, and other animals considered at risk on other farms involved in the disease occurrence also were vaccinated. Because of previous low demand, limited supplies of vaccine were available within the United States, and these supplies were quickly used up, creating an immediate lack of vaccine availability. The supplier, Fort Dodge, has undertaken to manufacture a large batch of vaccine, which should be available in October, in time to initiate a vaccination program prior to the onset of the 2007 breeding season.
Over the last two years there has been increasing evidence of equine arteritis virus infection within the Quarter Horse population when compared to the results of the National Animal Health Monitoring Survey (NAHMS) published in 1998. That survey indicated that the prevalence of infection within the breed was as low as 0.5%. At a meeting of Quarter Horse breeders, owners, trainers, and veterinarians, held at Ruidoso Downs in New Mexico August 17 coinciding with the annual sales, the feasibility of embarking on a vaccination program of stallions and possibly mares was addressed. Currently this proposal is under consideration. If there is agreement on a policy of vaccination, this policy will need to be implemented prior to the commencement of the 2007 breeding season. A recent study by Dr. Karin Bosh at the Maxwell H.
Gluck Equine Research Center examined the influence of management and veterinary factors on Thoroughbred broodmare reproductive efficiency. This article summarizes the development of an economic model as part of the study. Fortunately, the likelihood of this happening is very remote. For broodmare economics, a live foal is the critical production measure, because foals are the only source of production revenue. So, when we see what looks like flu in a horse that received an influenza vaccine last year, has the immunity from the vaccine worn off, or is the horse sick from a virus that we haven’t yet identified? There are many benefits from first cycle conception, including reduced breeding costs from eliminating repeated pre- and post-breeding veterinary treatments and reduced vanning costs. Earlier foaling dates may result in higher valued foals at sale due to greater weanling/yearling maturity and a reduced number of covers a stallion must make within the season.
Also, first-cycle conception minimizes the drift in a broodmare’s foaling date over time, which the study has shown to be a significant determinant of live foal rate. The conclusions reached were that rotavirus was a primary pathogen and was responsible for greater than 90% of outbreaks investigated. Costs were determined by defining best management practices through expert opinion from the panel of farm managers and veterinarians participating in the study. Breeding costs for broodmares conceived on the first cycle are $1,028 for barren broodmares, $902 for maiden broodmares, and $1,249 for foaling broodmares and include veterinary treatments and vanning costs. Costs increase $454 per cycle for each type of broodmare. The maintenance cost includes routine health and farrier costs plus a daily board rate of $26 per day for barren and maiden broodmares. Foaling broodmares have a board rate of $28 per day from March 29 to August 1 to account for the foal by the mare’s side.
Two additional major costs of breeding a broodmare are the stud fee and the annualized broodmare recovery cost. The stud fee is the largest production cost and is a highly correlated determinant of yearling value. Doll E.R., Bryans J.T., Immunization of young horses against viral rhinopneumonitis, Cornell Vet. The median stud fee of the broodmares in the study was $30,000 with a live foal guarantee. A broodmare is a capital asset, and depreciation cost recovery rules apply. The depreciation cost recovery period for young broodmares age 12 and under is seven years, and for broodmares over 12, the depreciation recovery period is three years. Depreciation represents the annualized capital cost of the broodmare.
The broodmare investment cost is held at $120,000 for all broodmare types, resulting in an annual capital cost of $17,143 for a young broodmare. Thompson about this vaccination. Although breeding costs are the lowest cost category, they produce the greatest marginal benefit, because these costs maximize reproduction efficiency. Breeders would be willing to invest in higher breeding costs if it increased the likelihood of a live foal. A broodmare’s annual cost will vary dependent on her quality. Higher quality broodmares have higher value and, therefore, a higher annual capital cost and will also be bred to higher quality stallions with higher stud fees. The annual breeding and maintenance costs are independent of broodmare quality and are the same for all broodmares regardless of quality.
Figure 1 illustrates the relative importance of breeding and maintenance costs in comparison to broodmare capital cost and stud fee. The graph clearly illustrates that as broodmare quality increases, the stud fees and broodmare capital costs dominate the cost structure of breeding broodmares. For foaling broodmares bred to a stallion with a stud fee of $1,000, the breeding and maintenance costs comprised 88% of the total costs to produce the live foal. For a foaling broodmare bred to a stallion with a stud fee of at least $70,000, the breeding and maintenance costs were less than 10% of the total production costs. By understanding how they work and how they?re made, you’ll be better equipped to make decisions about not only what diseases you’ll include in your horse’s vaccination, but also which vaccines to choose. Similar distributions were observed for maiden and barren broodmares. The level of stud fee/mare quality dictates opportunities for management to influence profitability through cost management practices.
Indeed, recombinant canarypox virus based vaccines for the prevention of equine influenza, West Nile virus or equine herpesvirus infections have already been developed for use in horses, and for the prevention of the closely related BTV in sheep –. Assessing reproductive performance in the horse has long been a topic of interest. The Kentucky study examined how farm level management and veterinary practices influence Thoroughbred broodmare reproductive efficiency. The project developed annual breeding and production costs. Work is ongoing to model the multiyear broodmare investment period and to incorporate the broodmare’s reproduction efficiency over time as part of the profitability of a Thoroughbred broodmare investment. molecular mass 10 kDa), molecular mass of the CT-null UL49.5 is approx. MLN were removed 5 days after i.n.
L. intracellularis has been reported to infect several species, including the pig, hamster, rabbit, non-human primate, dog, guinea pig, rat, mouse, fox, white-tailed deer, ferret, and selected birds. L. intracellularis most commonly causes proliferative enteropathy in foals 3 to 7 months of age, with a higher incidence in those recently weaned. Older horses also can be affected. A wide range of clinical signs can be associated with the disease, including diarrhea, dehydration, lethargy, colic, progressive weight loss, rough hair coat, poor body condition, and pendulous abdomen (potbelly appearance). Fuchs and D.
Gross lesions caused by L. intracellularis usually involve the distal jejunum, ileum, and proximal colon, although any portion of the intestinal tract can be affected. Pathologic lesions range from multifocal to confluent regions of mucosal hyperplasia. These hyperplastic mucosal regions can form circumferential areas as well as coalescing prominent folds or rugae (corrugated appearance). The affected mucosal surface may demonstrate variable degrees of erosion and/or ulceration. Ulcerated lesions can oftentimes lead to intestinal perforation and peritonitis. If administered to young foals in this manner, a third dose of the modified live vaccine should be administered 2 to 4 weeks before the foal is weaned to optimize protection during that time of high risk of infection.
Variable numbers of small and curved bacteria are located within the apical cytoplasm of hyperplastic enterocytes and are readily discernible when silver stains (Warthinstarry and Steiner’s) are applied to affected tissues. Minimal to no inflammation involving mononuclear cells is associated with proliferative enteropathy unless concurrent ulceration is present. Few diagnostic techniques are available to diagnose proliferative enteropathy. Ultrasonographic evaluations of the intestinal tract may reveal segmental to diffuse thickening of intestinal loops, depending on the severity and stage of the disease process. Additional antemortem diagnostic procedures include serology via ELISA and immunoperoxidase monolayer antigen assay, immunohistochemistry and Polymerase Chain Reaction (PCR) testing of fecal smears, mucosal scraping, and/or biopsies. Postmortem diagnostics include close gross evaluation of the entire intestinal tract during necropsy, silver staining of intestinal segments examined histologically, and PCR testing on mucosal scrapings of affected/diseased intestinal segments. PCR testing of mucosal scrapings is considered the most sensitive and specific of all aforementioned diagnostic procedures.
L. intracellularis cannot be cultured using conventional media, although it can be cultured on cell cultures under microaerophilic conditions. The incidence of young equids acquiring an infection with L. intracellularis has increased over the past five years within Central Kentucky. A prominent feature of O-glycosylation sites is an increased frequency of proline residues, especially at positions −1 or +3 relative to the glycosylated residue (Wilson et al., 1991). Late transcripts (γ1 and γ2) of ILTV could be detected in cells infected for 6 and 16 h without any drugs. Seventy-four of the 354 submitted samples had positive PCR results (21%).
These positive PCR results were obtained from horses residing on 157 farms within six Kentucky counties. Twenty-six out of the 74 positive PCR results were accompanied by necropsy specimens that demonstrated characteristic histologic lesions suggestive of an infection with Lawsonia (Figure 2). The preferred location for L. intracellularis is within the apical cytoplasm of enterocytes. Using antimicrobials that have the ability to penetrate cellular membranes is strongly recommended. Reports concerning Lawsonia infections in horses consider an Erythromycin-Rifampin combination to be the preferred and most effective treatment regimen. Additional antimicrobials reported efficacious for treatment include chlortetracycline, penicillin, enrofloxacin, chloramphenicol, and ampicillin.