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11.
Objective To evaluate the pre‐emptive analgesic effect of pre‐incisional epidural ketamine. Study Design A blinded, randomized experimental study. Animals Sixteen mixed breed mares, 7.6 ± 2.8 years old, weighing 352 ± 32 kg. Methods In a pilot study, an incision was made on one lateral thigh using a lidocaine block and no further analgesics, and it was verified that the nociceptive threshold was lower on the incised side than nonincised side (p ≤ 0.05), and that von Frey filaments evoked a pain response. The 16 animals were divided into group A (ketamine, n = 9) and B (saline, n = 7). An epidural catheter was inserted 24 hours before the trials. The thigh was shaved bilaterally, and the right side was blocked (incised side) using lidocaine. Twenty‐five minutes later, ketamine (A) or saline (B) was administered epidurally. Five minutes later, a 10‐cm skin incision was made on the right side, and then sutured. Nociceptive threshold was determined with von Frey filaments at 1, 3, and 5 cm around the incision at 15‐minute intervals for 2 hours, then at 4, 6, and 8 hours. Behavioral alterations, heart and respiratory rates were recorded. Nociceptive thresholds from these points were averaged to obtain mean values at each time, converted to a logarithmic scale, and submitted to a nonparametric analysis (Mann–Whitney and one‐way repeated measures anova test, p ≤ 0.05). Results After 8 hours, the global range score revealed reduced hyperalgesia (p < 0.01) around the incision in 92% (4.65–4.27) of evaluated intervals in group A (ketamine). There were no significant changes in behavior, heart and respiratory rates. Conclusions It was concluded that pre‐emptive epidural ketamine reduced post‐incisional pain in the horse, and that von Frey filaments were able to quantify cutaneous sensitivity after tissue damage. Clinical relevance Epidural ketamine injection can reduce post‐incisional sensitivity in the horse.  相似文献   
12.
A total of 17 microsatellite deoxyribonucleic acid loci used routinely for horse parentage control were used to evaluate genetic diversity among normal Arabian horses and severe combined immunodeficiency (SCID) carrier Arabian horses (ArS) and normal Arab-Barb horses and SCID carrier Arab-Barb horses (ArbeS). On the basis of the genotype of 186 horses, mean allelic diversity was estimated as 6.82, 5.53, and 6.7059 in normal Arabian horses, ArS, and for both groups of Arab-Barb horses, respectively. Five specific alleles were observed in ArS and ArbeS, with one common with ArS at HMS6, whereas five alleles common between ArS and ArbeS had a high frequency. Expected and observed heterozygosity showed great heterogeneity in the population studied and were similar or higher when compared with other studies on Arabian horses. Coefficient of gene differentiation Gst of Nei associated with Nei’s genetic distance and multivariate correspondence analysis indicated a possible differentiation between the studied populations when analyzed separately according to breed. Probability of assignment of a horse to a specific group was assessed using a full and partial Bayesian approach. In all, 80.6% of Arab horses and 78.2% of Arab-Barb horses were assigned properly with a partial Bayesian test, which provided better results than the full one. These findings will be useful for identification of SCID carrier horses by using the microsatellite deoxyribonucleic acid loci used routinely for horse parentage control in our laboratory.  相似文献   
13.
A survey of helminth parasites in stray dogs was carried out in the Zaria area. Out of 180 dogs examined 65.6 per cent (118/180) were found positive for Ancylostoma caninum, while Toxocara canis and Trichuris vulpis were detected in 41.1 per cent (74/180) and 13.9 per cent (25/180) respectively. Other helminth parasites found Taenia ovis 35 per cent (63/180) Taenia hydatigena 67.8 per cent (122/180), Echinococcus granulosus 0.006 per cent (1/180) and Dipylidium caninum 97.8 per cent (176/180).  相似文献   
14.
The oesophagus is a muscular tube comprised of cervical and thoracic regions. Several studies have clarified the histological structure of the oesophagus. However, its histoarchitecture in relation to variable dietary habits of each species is still unclear. In the current study, 21 pigeons, cattle egrets and ducks, n = 7, each was used. Macroscopically, the oesophagus of cattle egrets either the cervical or thoracic parts was the longest among the pigeons and ducks. Histologically, the oesophagus comprised of four distinct tunicae: mucosa, propria submucosa, musculosa and adventitia or serosa. A great structural variation in these layers among the three investigated species was recorded. In the cervical oesophagus of pigeons, the superficial squamous cells showed perinuclear halo zone, the propria submucosa was characteristically lacked any gland. Moreover, its musculosa was very thick. On the other hand, the intraepithelial glands were characteristically distributed along the whole length of the cattle egret’s oesophagus. Interestingly, the cervical esophagus of the ducks showed submucosal associated lymphatic tissue; diffuse and nodular Ultrastructurally, the oesophageal glands showed secretory granules of variable electron densities, electron - lucent in the pigeons and ducks and electron - dense in the cattle egrets.  相似文献   
15.
The prevalence of Sarcocystis spp. infection was investigated in 605 sheep, 826 goats, 1080 cattle, 580 water buffaloes and 36 camels slaughtered from 1992 to 1996 in the Baghdad area (Iraq) using naked eye examination for macroscopic sarcocysts, and peptic digestion, muscle squash, squeezing methods and indirect fluorescent antibody test (IFAT) for microscopic types. The intestinal stages of the parasite were also studied in dogs experimentally fed with tissues containing microscopic cysts. The percentage prevalence of macroscopic cysts were 4.1, 33.6, 0.2, 15.6 and 0, and of the microscopic type, 97.0, 97.4, 97.8, 82.9 and 91.6 for the above-mentioned hosts, respectively. Among the different organs examined, macroscopic cysts were found to be highest in the oesophagus and the lowest in the heart. Peptic digestion method gave the highest rate (93.3%) followed by indirect fluorescent antibody test (IFAT) (88.6%), squeezing (81.3%), and muscle squash (81.2%). Each infected dog shed a total of about 150-200 million sporocysts. Histologically, developmental stages of the parasite were detected in the small intestinal mucosa of the dogs on Days 7 and 13 post-infection.  相似文献   
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17.
Risk factors associated with injuries in thoroughbred horses.   总被引:2,自引:0,他引:2  
A case-control study was conducted on Thoroughbred horses to identify factors associated with the risk of breakdown on racetracks. A total of 310 cases (breakdowns) were identified from the Horse Identification Department records kept by the chief examining veterinarian of New York Racing Association. For each case, two control horses were selected randomly from the Daily Racing Form Inc. records. Multiple logistic regression analysis was used to identify and quantify the risk of factors associated with breakdown, while simultaneously controlling for the effect of other putative factors. Factors associated with risk of breakdown were: track (horses raced on Saratoga racetrack were at a lesser risk of breakdown), track composition/condition (turf tracks had a lower risk compared to dirt), number of seasons in race, racing in a later race, number of starts per year, the total number of starts, season (summer had a higher risk than winter or spring) and age of the horse.  相似文献   
18.
An indexing system for hygiene variables associated with egg production was developed by use of data collected from chicken flocks in southern California. The data were analyzed by factor and regression analysis. On the basis of our findings, hygiene index in relation to egg production consists of ventilation system, cooling system, manure removal, and truck movement. Flocks kept under natural ventilation produced, on the average, 2% more hen-day eggs than flocks kept under artificial ventilation. Flocks placed in houses with roof sprinklers produced 3.3% more hen-day eggs, compared with flocks placed in houses with inside foggers and pad. Flocks kept under the system of frequent removal of manure produced 2% more hen-day eggs than flocks kept under the system for which the manure was removed less frequently. Flocks kept in farms that restricted trucks collecting dead birds from entering the premises produced 3.4% more hen-day eggs than those that allowed such trucks to enter the farm.  相似文献   
19.
Tropical Animal Health and Production - The main objective of this research was to evaluate the effects of chemical treatment and sonication (ultrasound) processing on the fiber composition and...  相似文献   
20.
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