Topic:Prophylaxis
Prophylaxis in horses refers to the preventive measures and strategies implemented to protect equine health by reducing the risk of disease occurrence. These measures can include vaccinations, parasite control, nutrition management, and biosecurity practices. Vaccinations help to stimulate the horse's immune system to protect against specific infectious diseases. Parasite control programs aim to minimize the impact of internal and external parasites through strategic deworming and environmental management. Nutrition management ensures that horses receive balanced diets that support their overall health and immune function. Biosecurity practices involve procedures to prevent the introduction and spread of infectious agents within equine populations. This page gathers peer-reviewed research studies and scholarly articles that explore various prophylactic approaches, their implementation, and their effectiveness in maintaining equine health.
Evaluation of a commercially available hyperimmune plasma product for prevention of naturally acquired pneumonia caused by Rhodococcus equi in foals. To determine efficacy of a commercially available hyperimmune plasma product for prevention of naturally acquired pneumonia caused by Rhodococcus equi in foals. Methods: Randomized clinical trial. Methods: 165 foals. Methods: Foals were randomly assigned to 1 of 2 groups (hyperimmune plasma or nontreated controls). Foals with failure of passive transfer (FPT) of immunity were treated with hyperimmune plasma and evaluated as a third group. Foals that received plasma were given 950 ml between 1 and 10 days of age and between 30 and 50 days of age. A tracheobronchial aspirate was obtained from fo...
Evaluation of equine breeding farm management and preventative health practices as risk factors for development of Rhodococcus equi pneumonia in foals. To determine whether foal management practices, environmental management, and preventative health practices are risk factors for development of Rhodococcus equi pneumonia in foals. Methods: Prospective matched case-control study. Methods: 2,764 foals on 64 equine breeding farms with 9,991 horses. Methods: During 1997, participating veterinarians completed paired data collection forms for comparison; 1 for an affected farm (containing > or = 1 foal with pneumonia caused by R equi) and 1 for a control farm. Information collected pertained to stabling facilities, environmental management, foal hu...
Use of an active intra-abdominal drain in 67 horses. To describe the insertion technique, efficacy, and complications associated with the use of an active (closed-suction) abdominal drain in horses. Methods: Retrospective study. Animals-Sixty-seven horses with abdominal contamination treated by abdominal lavage and use of a closed-suction abdominal drain. Methods: Medical records of horses (1989-1996) that had a closed-suction abdominal drain were reviewed. Follow-up information was obtained by telephone interviews with owners. Results: Sixty-eight closed-suction abdominal drains were used in 67 horses that had abdominal contamination, peritonit...
The effect of aging on immune responses. Although vaccine manufacturers make no specific recommendations regarding the vaccination of older horses and ponies, the similarities in age-induced immunologic changes between human beings and equids suggests that similar vaccination recommendations should be followed. The need for vaccination of the older horse depends, of course, on the relative risk of exposure for the individual horse. Particular care should be taken when using attenuated vaccine products because these live agents may pose a unique risk to the older individual. Immunization with inactivated agent vaccines is likely to be...
Equid herpesvirus (EHV-1) live vaccine strain C147: efficacy against respiratory diseases following EHV types 1 and 4 challenges. The temperature sensitive and host range mutant clone 147 of equine herpesvirus 1 (EHV-1) was assessed for its ability to protect conventional, susceptible adult horses against respiratory infection by EHV-1 and equine herpesvirus 4 (EHV-4). Intranasal (IN) vaccination with 5.2 log(10) TCID(50) did not cause adverse clinical reactions although a limited virus shedding and viraemia (leukocytes) was observed in 11 of 15 and 10 of 15 vaccinated horses respectively. All 15 vaccinated horses showed a significant seroresponse to both EHV-1 and EHV-4 for virus neutralising (VN) antibody. None of 14 c...
Survival of foals with experimentally induced Rhodococcus equi infection given either hyperimmune plasma containing R. equi antibody or normal equine plasma. The purpose of this study was to determine if colostrum-deprived foals with experimentally induced Rhodococcus equi pneumonia have a decreased severity of the disease and decreased mortality rate when given hyperimmune (HI) R. equi antibody plasma (R. equi titer at least 100 % and virulence-associated protein A [VapA] at least 10000) prophylactically versus when given normal equine plasma (R. equi titer less than 20 % and VapA less than 160). Sixteen colostrum-deprived foals (R. equi titer less than 5 %) each received normal equine plasma in the first 24 hours of life (R. equi titer less than ...
Derivation and characterisation of a live equid herpes virus-1 (EHV-1) vaccine to protect against abortion and respiratory disease due to EHV-1. A German abortion isolate of EHV-1 (strain M8) was grown in equine dermal (ED) cells at a low multiplicity of infection in presence of 5-bromo-2-deoxy uridine. The resulting stock was dialysed, titrated and cloned by terminal dilution in ED cells grown in 96-well microtitration plates. Of 192 clones each originating from a single focus, clone 147 (C147) was found to be restricted for growth at and above temperatures of 38.5 degrees C. It was also restricted for growth at 37 degrees C in rabbit kidney (RK-13) cells which are widely used for the isolation and titration of EHV-1; hence clone 147 ...
Use of a high-molecular-weight carboxymethylcellulose in a tissue protective solution for prevention of postoperative abdominal adhesions in ponies. To evaluate efficacy and safety of IP administration of high-molecular-weight carboxymethylcellulose (HMW CMC) for the prevention of postoperative intra-abdominal adhesions in ponies. Methods: 10 ponies. Methods: A 1% solution of HMW CMC was instilled intra-abdominally prior to surgery in 5 ponies, whereas 5 control ponies did not receive HMW CMC. Postoperative adhesions were induced by use of a bowel-abrasion method comprising laparotomy, typhlotomy, and abrasion of jejunal serosa at multiple sites with placement of 3 sutures at each site. Day of surgery was day 0. After surgery, ponies were ...
Pharmacokinetics of imidocarb dipropionate in horses after intramuscular administration. The objective of this study was to determine the pharmacokinetic behaviour of imidocarb in horses following a single i.m. injection at the dose commonly administered to treat Babesia caballi infections or to prevent babesiosis. Eight horses were injected i.m. with a single dose of 2.4 mg imidocarb dipropionate/kg bwt and blood, faecal, urine and milk samples were collected. For imidocarb determination, a high-performance liquid chromatographic method (HPLC) was used after weak cation-exchange solid phase, or liquid-liquid, extraction procedures. Twelve hours after treatment, no detectable plas...
Survey of complications and antimicrobial use in equine patients at veterinary teaching hospitals that underwent surgery because of colic. To determine current practices regarding use of antimicrobials in equine patients undergoing surgery because of colic at veterinary teaching hospitals. Methods: Survey. Methods: Diplomates of the American College of Veterinary Surgeons performing equine surgery at veterinary teaching hospitals in the United States. Methods: A Web-based questionnaire was developed, and 85 surgeons were asked to participate. The first part of the survey requested demographic information and information about total number of colic surgeries performed at the hospital, number of colic surgeries performed by the res...
Effectiveness of a unique dihydropyridine (BAYTG 1000) for prevention of laminitis in horses. To determine whether a unique dihydropyridine (BAYTG 1000) would be beneficial in preventing laminitis in horses. Methods: 16 clinically normal adult horses. Methods: 8 pairs of horses were used in a controlled double-blind study, using sex- and age-matched horses randomly assigned to treatment or control groups. Horses were subjected to carbohydrate overload to induce laminitis. Treated horses were administered BAY TG 1000 (30 mg/kg, PO, q 24 h) for 3 days. Hoof wall surface temperature (HWST) and lameness were recorded at 4-hour intervals. The HWST was adjusted on the basis of time of onset ...
Duration of immunity induced by an adjuvanted and inactivated equine influenza, tetanus and equine herpesvirus 1 and 4 combination vaccine. An adjuvanted vaccine containing inactivated equine influenza, herpesvirus antigens, and tetanus toxoid was administered to young seronegative foals of 8 months of age by deep intramuscular injection in the neck (Group A). The first two vaccinations were given 4 weeks apart. The third was administered 6 months later. Another group of foals (Group B) was vaccinated according to the same scheme at the same time with monovalent equine herpes virus (EHV) vaccine (EHV1.4) vaccine. Antibody responses to the equine influenza (single radial haemolysis; SRH) and tetanus (ToBi ELISA) components of the v...
Efficacy of a cold-adapted, intranasal, equine influenza vaccine: challenge trials. A randomised, controlled, double-blind, influenza virus, aerosol challenge of horses was undertaken to determine the efficacy of a cold-adapted, temperature sensitive, modified-live virus, intranasal, equine influenza vaccine. Ninety 11-month-old influenza-naïve foals were assigned randomly to 3 groups (20 vaccinates and 10 controls per group) and challenged 5 weeks, 6 and 12 months after a single vaccination. Challenges were performed on Day 0 in a plastic-lined chamber. Between Days 1 and 10, animals were examined daily for evidence of clinical signs of influenza. Nasal swabs for virus isol...
NO inhalation reduces pulmonary arterial pressure but not hemorrhage in maximally exercising horses. In horses, the exercise-induced elevation of pulmonary arterial pressure (Ppa) is thought to play a deterministic role in exercise-induced pulmonary hemorrhage (EIPH), and thus treatment designed to lower Ppa might reasonably be expected to reduce EIPH. Five Thoroughbred horses were run on a treadmill to volitional fatigue (incremental step test) under nitric oxide (NO; inhaled 80 ppm) and control (N(2), same flow rate as per NO run) conditions (2 wk between trials; order randomized) to test the hypothesis that NO inhalation would reduce maximal Ppa but that this reduction may not necessarily ...
Trypanosoma evansi control and horse mortality in the Brazilian Pantanal. The impact of three treatment strategies for Trypanosoma evansi control on horse mortality in the Brazilian Pantanal based on four size categories of cattle ranches is explored. The region's 49,000 horses are indispensable to traditional extensive cattle ranching and T. evansi kills horses. About 13% of these horses would be lost, annually, due to T. evansi if no control were undertaken. One preventive and two curative treatment strategies are financially justifiable in the Pantanal. The best available technology for the treatment of T. evansi from a horse mortality perspective is the preventi...
Evaluation of equine immunoglobulin specific for Rhodococcus equi virulence-associated proteins A and C for use in protecting foals against Rhodococcus equi-induced pneumonia. To determine whether purified equine immunoglobulin specific for Rhodococcus equi virulence-associated proteins A and C (VapA and VapC) can confer passive protection against R. equi-induced pneumonia in foals. Methods: Twenty-eight 3-week-old mixed-breed pony foals. Methods: 7 foals received IV injections of equine hyperimmune plasma (HIP) against whole-cell R. equi, and 7 received purified equine immunoglobulin specific for VapA and VapC 1 day prior to intrabronchial infection with R. equi strain 103+. Eleven foals were not treated prior to infection, and 3 control foals were neither treated ...
Intranasal immunogenicity of a Delta cya Delta crp-pabA mutant of Salmonella enterica serotype Typhimurium for the horse. The aim of this study was to investigate the intranasal immunogenicity for the horse of a Deltacya Deltacrp-pabA mutant (MGN-707) of Salmonella enterica serotype Typhimurium (S. typhimurium). MGN-707 caused no sign of disease, was not detected in feces and a single administration induced strong Salmonella-specific serum and nasal mucosal antibody responses. All ponies had made strong salmonella specific serum IgGa, IgGb, IgA and IgM antibody responses by day 25 after the first immunization. IgM responses to salmonella lipopolysaccharide (LPS) were short lived whereas salmonella specific serum ...
One percent sodium carboxymethylcellulose prevents experimentally induced abdominal adhesions in horses. To evaluate the efficacy of 1% sodium carboxymethylcellulose (SCMC) for prevention of experimentally induced abdominal adhesions in horses. Methods: Prospective, controlled, experimental study. Methods: Twelve healthy adult horses. Methods: The effect of 1% SCMC on adhesion formation was evaluated in 12 healthy horses by using an established model of serosal trauma to induce intraabdominal adhesions. After ventral median celiotomy, 2 separate areas of the jejunum were abraded, and three 2-0 chromic gut sutures were placed in each abraded area. Jejunal resection and end-to-end anastomosis was p...
Field studies on equine influenza vaccination regimes in thoroughbred foals and yearlings. The purpose of these studies was to examine the response of Thoroughbred foals and yearlings to different influenza vaccines and vaccination regimes. The horses' antibody levels against haemagglutinin, an established correlate of protection were measured by haemagglutination inhibition. The first study investigated the extent to which maternal antibodies interfered with the humoral response to a subunit vaccine. The findings suggest that repeat vaccination in the face of maternal antibodies may induce tolerance as defined by serological testing. The second study compared the immune response el...
Postexposure rabies prophylaxis protocol for domestic animals and epidemiologic characteristics of rabies vaccination failures in Texas: 1995-1999. To determine whether postexposure rabies prophylaxis (PEP) in domestic animals, as mandated by the state of Texas, has continued to be effective and to evaluate PEP and preexposure rabies vaccination failures from 1995 through 1999. Methods: Retrospective study. Methods: 830 unvaccinated domestic animals (621 dogs, 78 horses, 71 cats, and 60 cattle) that received PEP and 4 animals (3 dogs and 1 horse) that had preexposure rabies vaccination failure. Methods: Zoonotic incident case reports from 1995 through 1999 were reviewed for information regarding unvaccinated domestic animals that received...
Getah virus as an equine pathogen. Getah virus is a member of the genus Alphavirus in the family Togaviridae and has been frequently isolated from mosquitoes. Seroepizootiologic studies indicate that the virus is mosquito-borne and widespread, ranging from Eurasia to southeast and far eastern Asia, the Pacific islands, and Australasia. The natural host animal of the virus was not known until the first recognized occurrence of Getah virus infection among racehorses in two training centers in Japan in 1978. Outbreaks of clinical disease due to Getah virus infection occur infrequently, and only one outbreak has been reported outsi...
Distribution of immunoglobulin isotypes and subisotypes in equine guttural pouch (auditory tube diverticulum). To clarify the functions of the equine guttural pouch, the distribution of various immunoglobulin isotypes and subisotypes in the guttural pouch mucosa were examined in healthy horses. IgGa was present in the mucosa of guttural pouch, mucosal lymph nodules and submucosal lymph nodules. IgM was scattered in the mucosal lymph nodules and in the germinal centers of the submucosal lymph nodules. IgGc was recognized only in the submucosal lymph nodules. These immunoglobulin isotypes and subisotypes were found in lymphocytes and plasma cells. On the other hand, IgA was detected in glandular epitheli...
Equine viral arteritis. Equine viral arteritis (EVA) can cause prominent economic losses for the equine industry. The purpose of this review is to provide the pathologist some familiarity with the clinical history, lesions, pathogenesis, and diagnosis of EVA. EVA is caused by an arterivirus (equine arteritis virus, EAV), and the vascular system is the principal but not unique viral target. EVA has variable presentations, including interstitial pneumonia, panvasculitis with edema, thrombosis and hemorrhage, lymphoid necrosis, renal tubular necrosis, abortion, and inflammation of male accessory genital glands. EAV anti...
Equine vaccination. Equine infectious disease remains a constant and important threat to the health of domesticated horses. Vaccination plays a critical role in protecting against such disease, but at the present time the efficacy of some equine vaccination strategies is in doubt. The best strategy for resolving these concerns is an improved knowledge of the immunologic basis of successful vaccination, combined with the appropriate integration of effective vaccines into well-designed disease control policies.
Equine T-cell cytokines. Protection and pathology. The ultimate reason for better characterizing the immune response to infectious agents is the hope that this knowledge may lead to the development of better preventative or therapeutic measures. As more information becomes available, it becomes possible to incorporate these findings into the design of better vaccines and treatments. Likewise, attempts to either enhance or suppress specific helper T-cell responses may be required to control immunopathologic reactions. Although cytokine intervention in the clinical setting remains theoretic at this time, future manipulation based on the TH1/TH2 ...
Secondary immunodeficiencies of horses. FPT of immunoglobulin in foals is the commonest form of acquired immunodeficiency in horses. FPT predisposes foals to bacterial infections and septicemia and easily is preventable and treatable if breeding farms and veterinarians are attentive to optimum foaling management practices. Other forms of acquired immunodeficiencies are uncommon in horses, although immune function may be transiently suppressed by a wide variety of drugs, infections, or other conditions. As immunologic testing becomes more sophisticated and more readily available to equine practitioners, acquired immunodeficiencies ar...