Epidemiology Diagnosis And Chemotherpy Of Strangles In Equines
Material type: Book ; Format:
Publisher: 2010 Dissertation note: Strangles is an infectious malady of equidae characterized by upper respiratory tract infection, dysponea, anorexia, regional suppurative lymphadenitis and causes high morbidity and low mortality. Considering the significance and utilization of equines in our country and the substantial losses rendered by Strangles, the present project was designed to study epidemiology, diagnosis and chemotherapy of strangles in Lahore and Sargodha districts of the Punjab province in Pakistan.
The present study comprised of five phases. In phase-I, epidemiology of the disease including prevalence, variations in SeM, SzPSe and Se18.9 proteins and mortality rate were studied in Lahore and Sargodha districts. For epidemiology, nasal swabs and pus samples from the affected lymph nodes of 500 equines (nr=250 horses, rutz250 mules) suspected for strangles were collected and cultured for identification of S. equl. The collected samples were processed at Medicine and Microbiology Laboratories of the University of Veterinary and Animal Sciences, Lhore, Pakistan and Gluck equine research center, Department of Veterinary Science, University of Kentucky, USA. Out of 250 horses and 250 mules, 113(45.2%) horses and 99 (3 9.6%) mules tested positive for S. equi. on the basis of culture. Number of S. equl isolates were significantly higher (P<0.05) in pus samples taken from sub-mandibular lymph nodes as compared to nasal discharge samples. The difference was significant (P<0.05) among mules of different age groups. The highest prevalence of strangles
was recorded in horses and mules less than 2 year of age as compared to those having age more than 2 years.
In the present study, prevalence of strangles round the year in horses and mules were also calculated and it was found to be the highest during the months of
February, March, April and May while few cases were seen during the months of January, June and July and no cases were observed during others months. The significant difference was observed (p<O.O5) among the prevalence levels of strangles in different months of the year. Similarly when compared the prevalence of strangles in different seasons of Pakistan i.e. summer, winter, spring and autumn. The highest prevalence rate was recorded during the spring season.
The prevalence on the basis of Polymerase chain reaction (PCR) of S. equi in horses and mules was also recorded. Out of 250 horses and 250 mules tested, 122(48.8%) horses and 113(45.2%) mules were positive for S. equi. When compared
the prevalence rate on the basis of PCR and culture of nasal and pus samples from affected submandibular lymph nodes it revealed that the sensitivity of Polymerase
chain reaction appears to be much greater than culture. The culture along with PCR is the best diagnostic technique for S. equi as PCR test does not differentiate between dead and live bacteria, hence a positive test may not correlate with active infection; therefore, a positive culture may be necessary to confirm the diagnosis.
In this phase of epidemiological study of disease, effect of selective pressure of allelic diversity in SeM of S. equi on immunoreactive proteins SzPSe and Se 18.9 was also studied. The aim of this study was to determine whether variations in SeM are accompanied by variations in the immunoreactive surface of exposed SzPSe and secreted Se18.9. Sequences of genes of 25 S. equi alleles isolated from different countries of the world over a period of 40 years were compared. Twenty different SeM alleles were identified including 6 not included in the data base (http:// pubmlst.org/szooepidemicus). Amino acid variation was also detected distal to the N- terminus of SeM. No variation was observed in SzPSe except for an Australian isolate which showed a deletion of one PEPK repeat. The Se 18.9 protein in all 25 isolates of S. equi did not exhibit any variation. Interestingly, only 2 SNP loci were detected in Se 18.9 compared to 93 and 49 in SeM and SzPSe respectively. The greater frequency of mutation in SzPSe compared to Se18.9 may be related to a high rate of recombination of SzPSe and the inclusion of exogenous DNA sequence based on the atypical GC percentage of its central hyper variable region.
In horses the mortality rate was recorded as 1.64% whereas the mortality rate in mules having less than 5 years of age was found to be 0.88%. No significant difference (P>0.05) in mortality rate among horses and mules of different age groups affected with strangles was observed.
In phase-I! of the present study, carrier status of the horses and mules were
studied. Out of 122 horses found positive to PCR, 20 horses (10<2 years and 10 between 2 and 5 years of age) were selected and monitored for 12 weeks. Their nasal
swab samples were used for identification of bacteria through culture and PCR on weekly basis. Till the end of 3rd week all horses <2 years of age remained positive but at the end of 4th to 7th weeks there remained positive only 5, 2, 1 and zero horses out of 10, respectively on the basis of culture whereas through PCR at the end of the 4th week all horse <2 years of age were found positive, but at the end of 5th to 10th weeks there remained 7, 5, 4, 2, 1 and zero horses out of 10, respectively. While all the horses aging between 2 to 5 year, were positive up to the 1St week but at the end of 2nd to 8th week out of 10 there were 9, 7, 6, 3, 1, 1 and zero horses respectively positive on the basis of culture but through PCR, all horses were positive till 4th week but at the end of 5th to 9th week number was reduced to 9, 7, 6, 3, 2 and zero. Similarly, out of 113 mules, 20 mules (10<2 year and 10 between 2 and 5 years of old) were also monitored for 12 weeks to study their carrier status. After the end of 2nd week all mules <2 years of age were positive but at the end of 3rd to 6th weeks there remained 7, 3, 1 and zero mules out of 10, respectively on the basis of culture but through PCR at the end of the 5th week all mules <2 years of age were positive, but at the end of 6th to 10th weeks there remained 9, 7, 3, 2 and zero mules out of 10, respectively. While in 2 and 5 year old mules, all were positive up to the 2nd week but at the end of 3rd to 7th weeks there were 6, 4, 2, 1, 1 and zero mules out of 10, respectively on the basis of culture but through PCR, all mules were positive up to 5th week but at the end of 6th to 10th weeks there were 8, 5, 2, 1 and zero. Horses and mules were declared free of infection on the basis of three consecutive negative samples through culture and PCR.
From the result of present study, it may be concluded that sensitivity of Polymerase Chain Reaction appears to be much greater than culture for study of carrier status of equines. Moreover, recovered animals should be kept in quarantine period at least upto 9th week because the recovered horses and mules remain carrier for prolonged period of time and can act as source of infection for susceptible animals through periodic shedding of S equi. (comprising 10 horses and 10 mules) for in-vivo trials. Efficacy of the antibiotics was assessed weekly on the basis of negative nasal swab culture. Results of in-vitro antibiotic sensitivity revealed that in horses and mules, S equi was most sensitive to Procaine penicillin followed by ceftiofur Na, cephradine, erythromycin, ampicillin, tetracycline, chloramphenicol, sulfamethoxazole, trimethoprim + sulfdiazine and gentamycin whereas the result of in-vivo antibiotic trials revealed that horses and mules suffered from strangles without abscess formation were most sensitive to Procaine penicillin followed by ceftiofur Na, cephradine and erythromycin whereas animals which developed abscess showed no response. It is concluded from the result of present study that Procaine penicillin is most effective in-vitro and in-vivo antibiotic followed by ceftiofur Na and cephradine. These antibiotics might be used for the treatment of strangles infection.
Phase-V, comprised over in-vitro trials of disinfectants. Efficacy of disinfectants, like povidone iodine, 0.6% H2S04, dettol and bleach was assessed. Phenol Co-efficient Test was applied, to ascertain efficacy of these disinfectants, used
in, in-vitro trials. Among four disinfectants, povidone iodine was found to be the best one with a phenol coefficient of 1.25 that is greater than phenol i.e. 1.00 while 0.6%
H2S04 showed similar phenol coefficient as that of phenol. The phenol coefficient of dettol and bleach were observed as 0.5 and 0.75 respectively. Therefore it is recommended that S. equi is highly sensitive to povidone iodine and 0.6% H2S04.
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Studies On Cyanide Toxicity In Ruminants
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Publisher: 2011 Dissertation note: The present study was conducted with the objectives to: (a) determine the cyanogenic potential of various livestock fodder and grasses, (b) determine CN? content in blood of ruminants feeding cyanogenic plants, (c) develop a simple, reliable and inexpensive assay for the determination of CN? in blood, (d) evaluate the efficacy of various antidotes against CN? toxicity in a rabbit model, (e) find out the effect of CN? on hematological and biochemical profile, (f) study the postmortem and histopathological changes associated with CN? toxicity in various organs and (g) study alterations in tissue oxygenation and metabolic variables during acute CN? toxicity in pigs. For this purpose a total of 500 samples of various plants being used as fodder to livestock were collected from the field and analyzed for CN? content spectrophotometerically. To develop a simple picrate method for CN? estimation in blood, two goats were infused with KCN at 0.6mg/kg for 1 hours. Blood samples were collected at intervals and were subjected to the general method. Standard curve was developed using standard solutions of various concentrations of CN?. Additionally 6 rabbits were also given CN? orally for 40 days and blood samples were collected for CN? estimation. Later on, this method was successfully used to determine CN? levels from 500 blood samples of cattle, buffaloes, sheep and goats (n=125 each) feeding cyanogenic plants which were collected from the field. For antidotal studies forty two rabbits were randomly divided into seven groups viz. A, B, C, D, E, F and G each comprising of six animals. Rabbits in group A were given feed only and served as negative control, while the rabbits in group B received feed plus oral solution of potassium cyanide (KCN) and were positive control. Animals in group C were given feed, KCN and intraperitoneal (IP) injection of garlic extract. Rabbits in group D were treated with feed, KCN and IP injection of sodium thiosulfate (STS). Members in group E received feed, KCN and IP injection of both garlic extract and sodium nitrite (SNT). Animals in group F were treated with feed, KCN and IP injection of both STS and SNT whereas the rabbits in group G were given feed, KCN and hydroxocobalamin IP. The treatments were given to respective groups for a period of 40 days. At the end of 40 days, serum and fresh urine samples were drawn from each rabbit to study biochemical panel. Subsequently the rabbits were euthanized for postmortem and histopathological changes in various organs. For hematological and growth rate studies 12 rabbits were divided into two groups of six viz. A and B. Rabbits in group A were given feed only while members in group B were treated with feed and oral KCN at 3mg/kg for 40 days. The animals were weighed after every 10 days. Feed consumption rate, feed efficiency and weight gain for the members of each group were recorded. Blood samples were also collected for hematological studies at 0, 10, 20, 30 and 40 days. To study tissue oxygen and metabolic variables during acute CN? toxicity, 26 piglets were anesthetized. The non-invasive monitors were used to measured oxygen saturation, heart rate and rhythm and cerebral response to sedation. The invasive monitors were placed to measured beat to beat variability of the arterial blood pressure, pulmonary artery pressures. Mixed venous oxygen saturation (SvO2) and cardiac output were continuously monitored. Regional brain O2 (cerebral cortex) and skeletal muscle O2 saturation (rSO2) were also measured via sensors. After getting baseline metabolic and hemodynamic measurements that included arterial and venous blood gas analysis, lactates and cyanide levels, all pigs were started on an infusion of NaCN (0.55 mg/kg/hr). The infusion continued until the occurrence of sustained apnea (?3 minutes). A non-significant difference was found in the CN? content of Sorghum bicolor and S. sudanese, while a significant difference was observed between the CN? content of Jumbo grass (S. bicolor x S. Sudanese hybrid) and S. halepense. Jumbo grass and S. halepense were found to have significantly higher CN? concentrations than S. bicolor or S. Sudanese. Maize has significantly lower CN? content compared to S. bicolor, S. sudanese, Jumbo grass, or S. halepense. A gradual increase in CN? content with increasing height of plants was also observed. Highest CN? levels were observed at heights of 91-100 cm in sorghum varieties. At greater heights, a gradual decrease in CN? content was seen in all plant species, with the lowest levels at heights of 200 cm or above. No CN? was detected in maize at heights over 131 cm. In picrate method, the calibration curve was linear (R2=0.99) in the range of 0.3-120 mg CN?/L. In standard CN? solutions a color change in picrate paper from yellow to brown was observed at a concentration of 3 mg CN?/L and above. This method was sufficiently sensitive to quantify the low concentrations (0.3mg CN?/L) of CN? found in ruminant blood. In goats infused with KCN, the CN? concentration in blood was time-dependent and continued rising during infusion, gradually declining after infusion ceased after 1 h. Blood CN? levels showed a time-dependent increase in all experimental rabbits with the maximum concentration (1.34 mg/L) at day 40. The highest blood CN? concentrations were found in cattle, followed by goats and buffalo, with the lowest in sheep. When blood CN? levels of these species were compared statistically, a non-significant difference was observed. A non-significant difference was found between males and females. No relationship was observed between blood CN? levels and age of the animal for any species. Buffalo, cattle, sheep, and goats allowed to graze showed significantly higher blood CN? levels than animals kept in a stall feeding system. Animals grazing on jumbo grass were found to have significantly higher blood CN? levels than those fed S. bicolor or S. sudanese with a non-significant difference found between animals fed S. bicolor or S. sudanese. No CN? was detected in blood samples of animals fed maize. Hydroxocobalamine was found to be a significantly more effective CN? antidote than garlic, STS, SNT plus garlic extract, or SNT and STS, either alone or in combination. A combination of SNT and garlic extract was the second most effective CN? antidote. The efficacy of garlic alone was significantly higher than STS or SNT in combination with STS. The efficacy of combined SNT and STS was superior to STS alone in treating rabbits with CN? toxicity. No rabbits in any group demonstrated gross deviation from the normal organ structure. The activities of serum ALT, AST, ALP, and LDH enzymes, as well as serum bilirubin, were significantly increased in CN? treated rabbits compared to controls. Severe hepatocyte vacuolation and degeneration were present in liver of rabbits in the CN? treated group. Liver of rabbits in the control group showed normal morphological patterns. The concentrations of serum urea, uric acid and creatinine were significantly higher in CN? treated rabbits than in control group. Urinary thiocyanate levels were also significantly higher in the CN? group than in controls. Kidneys of rabbits in the CN? group demonstrated severe glomerular and tubular necrosis and congestion. Pyknotic nuclei were present in tubular epithelial cells, whereas a normal histological pattern was observed in kidneys of rabbits in control group. Serum T3 and T4 levels were significantly lower in the CN? group compared to controls. A non-significant difference in blood glucose levels was recorded between rabbits in control and CN? treated groups, and histological examination of pancreas revealed no microscopic lesions. No significant differences were observed in serum cholesterol levels of CN? and control group rabbits. The serum albumin and total protein concentration in CN? treated rabbits were significantly lower than in the control group. Heart of rabbits in both CN? and control group did not show histopathological changes under microscopic examination. The erythrocyte count, the hemoglobin concentration, packed cell volume and mean corpuscular hemoglobin were all found to be significantly lower in blood of CN? treated rabbits than control group. The mean corpuscular hemoglobin concentration was significantly higher in the CN? group rabbits than control group animals. On the other hand, the difference in leukocyte count, differential leukocyte count and platelets were non-significant. The difference in total and daily feed consumption between CN? and control group rabbits was non-significant, whereas the feed efficiency of rabbits in the control group was significantly higher than for rabbits in CN? fed group. The net weight gain of rabbits in the control group was significantly higher than in the CN? fed group. Cyanide infusion to pigs resulted in toxic levels of blood CN? accompanied by lactic acidosis. In addition, there was a progressive increase in cardiac output, Venous oxygen saturation, heart rate, elevation of central venous pressure and pulmonary artery blood pressure. Skeletal muscle rSO2 progressively and significantly decreased with increasing lactate and CN? levels. However, there was no significant change in brain rSO2.
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Epidemiology And Prophylaxis Of Babesiosis In Felidae
Material type: Book ; Format:
; Literary form:
Publisher: 2011 Dissertation note: Abstract
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Epidemiological, Haematological & Serological Studies Of Leptospirosis In Dogs And Human At High Risk In And Around Lahore City
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Publisher: 2013 Dissertation note: Leptospirosis is an important zoonosis of global importance capable of causing significant subclinical and clinical syndromes both in humans and animals. The disease is characterized by fever, vomiting, diarrhea, myalgia and other signs consistent with renal and hepatic disease. Considering the significance and the substantial losses rendered by Leptospirosis, the present project was designed to study epidemiology and haematology in dogs and humans at high risk in Lahore district and its peri-urban areas.
The study was accomplished in 4 phases. In phase-I, sero-prevalence both in dogs and human was studied including case fatality rate and associated risk factors through cross a sectional study. For this purpose, blood samples were collected from dogs attended at the Pet Centre of University of Veterinary and Animal Sciences, Lahore and other private clinics situated in and around Lahore area through systematic random sampling technique over a period of one year (1st Dec. 2010 to 30th Nov.2011). Blood samples from every fifth un vaccinated dog were collected, but if the dog was vaccinated then the sample was collected from the next unvaccinated one. In this phase 100 sera samples from human volunteers which were at maximum risk (veterinarian, pet and livestock owners, para-vet staff) were also collected. All samples were screened out by using ELISA kits like Canine Leptospira IgG ELISA Kit Catalog no. BG-CAN11485, NovaTein Biosciences, Woburn, MA, USA and Serion Elisa Plate, Virion/Serion GmbH, Wurzburg, Germany for dogs and humans respectively at the Medicine Laboratory and University Diagnostic Laboratory, University of Veterinary and Animal Sciences, Lahore.
To study overall prevalence of Leptospirosis in dogs a total of 429 dogs were examined and it was found that out of 429 blood samples 155 were found positive for Leptospira antibodies. Thus an overall prevalence of Leptospira was recorded as 36.13%. Prevalence of Leptospirosis in dogs during different months of the year was also recorded. The months of September, October and June showed ere the highest prevalence and recorded as 50%, 48.57% and 45% respectively. Although, a few cases were seen during the months of December, January and February while moderate number of cases was recorded during the rest months of the year. There was a significant difference (p<0.05) in the prevalence of Leptospirosis during the different months of the year. Out of these 429, 93 pups and 336 adults were examined for Leptospirosis and found that 26 pups and 129 adults were positive i.e. a prevalence rate of 27.95% (26/93) and 38.39% (129/336) for Leptospirosis was recorded in pups and adult dogs respectively and this difference was non-significant (p>0.05). In this study a prevalence rate of 38.49% (102/265) and 32.31% (53/164) for Leptospirosis was recorded in male and female dogs respectively and this difference between the sexes was also non-significant(p>0.05). According to the results of this study a sero-prevalence of 21.24% (24/113) in winter, 35.82% (24/63) in spring, 40.34% (71/176) in summer and 49.32% (36/73) were recorded in fall season and this difference was significant (p<0.05). The highest prevalence rate was observed in fall and summer seasons of the year during higher rain fall seasons of the year.
To study overall prevalence of Leptospirosis in humans, a total of 100 blood samples were examined through random sampling technique during the whole study period and overall prevalence rate of 44.00% was observed in human population. Different risk factors like different months of the year, age, sex and season were also studied and that the highest prevalence of Leptospira in humans was observed in the months of March, April and August i.e. 66.66%, 66.66% and 60.0% respectively. No significant difference (p>0.05) in the sero-prevalence of Leptospirosis in human during the different months of the year was observed. Sex-wise prevalence rate of 48.71% (38/78) and 27.27% (06/22) for Leptospirosis was recorded in male and female respectively and this difference was significant (p<0.05). The results of this research project revealed a prevalence rate of 47.29% (35/74) and 34.61% (09/26) for Leptospirosis in adults and young ones respectively and this difference was again non-significant (p>0.05). According to the results of this study a sero-prevalence of 41.93% (13/31) in summer, 40.00% (06/15) in fall and 25.92% (07/27) in winter, while 66.66% (18/27) was recorded in spring season of the year and this difference was significant (p<0.05) and the highest prevalence rate was observed in spring.
In phase-II, the effect of Leptospirosis on various blood parameters were determined in both dogs and human. The results of present study revealed a significant difference (P<0.05) between the Hemoglobin (Hb), Erythrocytic sedimentation rate (ESR), Packed cell volume (PCV), Total Leukocytic count (TLC), Neutrophils, Eosinophils and Monocytes of healthy and Leptospira affected dogs, while a non-significant difference was observed (P >0.05)among values of lymphocytes. It showed that values of Hb forthe diseased dogs were lower than healthy ones while ESR, PCV, TLC, Neutrophils, Eosinophils and Monocytes, were more than in normal dogs. Likewise, in humans all the studied parameters were significantly (P <0.05) different between infected and healthy ones. The values of Hb concentration in diseased humans were lower than the healthy ones while ESR, PCV, TLC, Neutrophils, Eosinophils, Basophils, and Monocytes were higher than in healthy people. A negligible change was observed in the percentage count of lymphocytes.
In phase-III, the comparative efficacy of commercially available vaccines against Leptospira was studied. Two commercially available vaccines, Vaccine #1 with protection against two serotypes of Leptospira (Canicola, Icterohaemorragiae) and vaccine #2with protection against four serovars of Leptospira i.e Canicola, Icterohaemorrhagiae, Grippotyphosa and Pomona were compared After six months it was observed through ELISA screening that the vaccine #2 provided better overall protection compared to the vaccine #1 to the pups as well as adult dogs against the Leptospirosis but this difference was non-significant (p>0.05).
In the last phase of this study the chemotherapy trial was conducted. Results found that the efficacy of Penicillin G was 70%, while in group B Amoxicillin produced 60% results and in group C Sarsaparilla proved to be 40% effective against this infection although this difference was non-significant (p>0.05). It is concluded that among therapeutic agents used to treat Leptospirosis in dogs, Penicillin G , Amoxicillin and Sarsaparilla are ranked in respective order of efficacies.
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Clinico-Epidemiological And Experimental Observations On Feline Lower Urinary Tract Disease Among Domesticated Cats
Material type: Book ; Literary form:
Publisher: 2015 Dissertation note: Idiopathic Feline Lower Urinary Tract Disease (iFLUTD) has been known as a major as well as important problem throughout the world especially the veterinary profession. Nicks of this problem also found in Pakistan, however the veterinarians are usually unable to properly diagnose this disease due to lack of knowledge as well as the ancillary diagnostic equipment availability for this disease. Present study was divided into two phases. Phase – 1 included clinico-epidemiological data. To this end, target of more than 502 domesticated client-owned cats of either sex, age, breed, etc showing signs of feline lower urinary tract disease (FLUTD) as per Buffington (1994) were examined accordingly from 3 different cities (Lahore, Faisalabad, and Islamabad) of Pakistan). All data collected was based on a predesigned proforma by using structured interview of the owners. Diagnosis was solely based on serum-cortisol levels, urinalysis, radiography and ultrasonography. Phase II involved experimental trial. The data obtained from whole of the study was then presented in tabulated form as frequencies and percentages. Treatment and outcome of the disease were also analyzed accordingly.
According to the present study conducted it is proved that iFLUTD is present among the cats in Pakistan. Its proper cognizance among the Pakistani veterinarians is still non-existent and is misdiagnosed as colic or constipation issues in cats. The present study was undertaken to bring iFLUTD into the reportive of small animal practitioners working in Pakistan. The present study debunked various previous notions like iFLUTD is associated with commercial diets and canned foods only if we talk about this region majority of cases were noticed that had home-cooked food given by the owner. Moreover, cases in Siamese breed are larger than Persian breed. It has been strongly associated with Indoor housing management. Additional work is still needed to explore untouched areas of epidemiology including factors other than those being studied in the previous literature. Academicians in veterinary pathology and veterinary medicine of Pakistani universities should embrace this malady in the Doctor of Veterinary Medicine (DVM) curricula.
According to the present study results it is concluded that two factors like stress and pain accelerate the sympathetic nervous system outflow compared to normal felines leading to the inflammatory response. Thus the stress factor must be reduced in the form of making hiding places for cats at home to reduced down the fear factor along with enhancing the feeling of owes for that particular place. Moreover, some more practices should be performed by the owner to reduce down the stress factor like playing with the pet, giving full attention, placing toys and other attractive things like yarn balls at the feline places (where they live/placed). There was no significant difference found between the groups based on the food with health score along with the therapeutic judgment. Hence, it is recommended that more experiments should be performed on larger scale to assess GAG therapy on increased number of felines and need of hour is to conduct more veterinary studies to get information and authenticity for its use against iFLUTD.
From this study conducted, I recommend to the owners that the cats must be provided with the indoor hiding places and play with their pets in order to reduce the stress factor that increases the risk of idiopathic lower urinary tract disease. Moreover, the trend of home-cooked diet should be reduced along with increase in water intake by the cat.
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A Study On Postural Sway In Horses During Different Sedation Protocols Along With Clinico-Biochemical Evaluation In Clinical Cases
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Publisher: 2017 Dissertation note: 6.1. Observational study of postural sway using accelerometer in horses sedated with different sedative combinations
Balance is the ability to maintain center of gravity by a body within the base of support, whereas the phenomenon of continuous movement and improvement of the position of the center of gravity within the base of support is referred to as postural sway. Most of the living creatures including man, horse and other animals need to maintain their postural balance for their daily requirements, as most of them are either bipeds or quadrupeds. To attain this balance, co-ordination between sensory system, skeletal muscle system and the central nervous system is required. These systems are responsible for the pattern of walk in the horses, which is called as gait. Any abnormality in the nervous system results in an altered gait, which if assessed properly is a useful tool in diagnosing many ailments & disorders of the locomotor system. To assess these changes in the gait pattern, many methods have evolved over the years. The gait can be assessed by Kinematic or Kinetic Analysis. An accelerometer is a detecting element that measures acceleration. Accelerometers can measure: vibrations, shocks, tilt, impacts and motion of an object. An accelerometer by itself is only a sensing element, in order for it to be useful the sensor needs to be combined with other elements such as, power, logic, memory and a means to translate the output. An acceleration recorder incorporates all of these elements into one package.
There is a measurable difference in postural sway at stance between different sedation protocols. This study aims to document and quantify the postural sway of horses undergoing various sedation protocols, with the aim of identifying a sedation protocol that will reduce sway and improve the ease with which standing non-painful diagnostic imaging procedures (Radiography, Scintigraphy and MRI) can be carried out. The present study assessed the postural sway during sedation in horses and evaluated a sedation protocol with minimal sway in horses. Equine surgery depends heavily on various imaging procedures. Diagnostic imaging plays important roles-first, in diagnosing and localising a disease process; second, in assessing the surgical intervention to be applied; and third, in the follow-up evaluation of the patient. Many imaging techniques like Radiography, Ultrasonography, Scintigraphy, Magnetic Resonance Imaging and Computed Tomography are used at veterinary hospitals and clinics, the world over. In order to achieve good results for these diagnostic modalities, various drugs and their combinations have been used by scientists to achieve good standing sedation in horses (e.g., Acepromazine, Butorphanol, Detomidine, Ketamine, Romifidine, Xylazine, etc.). The reason for integrating sedations which use combinations with Ketamine in this study and its different effect on the musculature i.e. increasing the muscle tone, while the alpha2-agonists (Romifidine, Detomidine, Xylazine), all reduced the muscle tone. Potentially, increasing the muscle tone of a horse will reduce the sway, as the constant correction of postural position with reduced muscle tone may be avoided. Horses that are In-Patients and Out-Patients brought to the Large Animal Hospital, Dept. of Vet. Clinical Studies, EBVC, RDSVS, UoE, UK, and have the medical need for diagnostic imaging procedures, and that require sedation so that these procedures can be carried out safely, were included in the study. The measurements were recorded pre-sedation and post-sedation while the horse is being imaged. The horses were observed during Radiography, Ultrasonography, Scintigraphy and Magnetic Resonance Imaging, or some other minor/major surgical intervention, under the influence of standing sedation. The body sway was measured using a MicroStrain G-link wireless triaxial accelerometer. It was secured on the skin above the midline of the sacrum with adhesive tape. Both sway episodes as well as continuous postural adaptations was assessed from the sum vector of the three acceleration traces.
The results of current study showed no significant difference (p>0.05) in the mean values of postural sway between different drug groups. All drug combinations produced sedation in standing horses. However, pre-sedation mean values were significantly different from post-sedation mean values of postural sway. This shows that the subjects which were administered different combinations of sedatives exhibited variation in the postural control over time that is the readings of accelerometer either increased or decreased after sedation when compared to baseline (pre-sedation) values. The findings of current investigation also revealed a significant combined effect of drug groups and measurement time. Which means that the horses within groups, administered with different sedative combinations showed a change in postural sway values measured by accelerometer over time and these mean values either increased or decreased post-sedation. However, Post hoc Tukey’s test could not establish a significant difference (p<0.05) in the multiple comparision tests. Although post-sedation mean values of postural sway of group 2 (romifidine alone) and group 7 (detomidine alone) were different from pre-sedation values (p<0.1).
The mean values of accelerometer for group 1 (detomidine+butorphenol) and group 4 (xylazine alone) were decreased from pre-sedation values that means the horses in these groups were more stable and had better control over their stance when compared with pre-sedation values. In the current study, the mean values of accelerometer for group 2 (romifidine alone) and group 7 (detomidine alone) were increased from pre-sedation values that means the horses in these groups were less stable and had poor control over their stance. This showed that detomidine alone with a dose range of 3 to 9 μg/kg is insufficient for standing procedures.
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