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91.

Background

The pathogenic mechanism of equine recurrent uveitis (ERU) is still poorly defined and many variations between experimental animal models and spontaneous disease exist.

Objectives

The aim of our study was to investigate if Th17 cell-mediated response plays role in the pathogenesis of the used experimental model in horses and to reveal its pathological findings.

Methods

Experimental uveitis was induced in 6 healthy horses. The concentrations of retinal autoantigen CRALBP and IL-17 were measured using ELISA in aqueous humor and vitreous body of the 12 inflamed eyes as well as in 12 control non-inflamed eyes taken from 6 horses in slaughter house. After centrifugation of the two eye media, smears were prepared and cytological investigation was performed. Tissue specimens were taken from all eye globes and were submitted to histopathological investigation.

Results

CRALBP and IL-17 concentrations were significantly elevated in eye media of horses with experimental uveitis in comparison with controls. Cytological and histopathological findings corresponded to the changes characteristic of chronic immune-mediated inflammation with mononuclear cell infiltration of uvea, choroid, retina, and eye media as well as severe retinal destruction.

Conclusions

Our study demonstrated the involvement of the retinal autoantigen CRALBP as well as IL-17 in the pathogenesis of experimental uveitis in horses. These findings suggests that this experimental uveitis in horses may serve as a suitable animal model for investigation of IL-17- mediated immune response during spontaneous autoimmune uveitis in horses as well as in humans.
  相似文献   
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Plasma concentrations of PAG‐1 are used for pregnancy diagnosis and as a marker of placental/foetal well‐being, while those of PAG‐2 may be an indicator of abortion risk in Neospora caninum‐infected cows. Studies have shown that N. caninum infection modifies PAG‐1 and PAG‐2 patterns in maternal blood plasma. However, no prior work has examined the effects of N. caninum infection on concentrations of PAGs in foetal fluids. In this study, PAG‐1, PAG‐2 and pH levels were determined in the amniotic and allantoic fluids of foetuses collected at 152 days of gestation from control uninfected dams and from dams experimentally infected with N. caninum on Day 110 of gestation. Foetal fluids from infected foetuses had significantly higher PAG‐2 concentrations (p = 0.026) and pH values (p = 0.02) than fluids from non‐infected foetuses. In infected foetuses, significantly higher concentrations of PAG‐1 (p < 0.001) and PAG‐2 (p < 0.001) were detected in fluid samples showing antibodies against N. caninum than those without antibodies. Moreover, pH values were significantly higher (p = 0.011) in foetal fluid samples with antibodies than in samples from non‐infected foetuses. In conclusion, this is the first report on the effect of N. caninum infection on PAG levels in foetal fluids. Our results indicate that following the experimental infection of dams with N. caninum on Day 110 of gestation, foetal fluids collected from the infected foetuses of these dams featured higher PAG‐1 and PAG‐2 levels and pH values than fluids from non‐infected controls, provided that the samples tested showed the presence of antibodies. The clinical implications of these findings are that following infection with N. caninum, most cows will experience some level of placental damage and that this injury correlates with foetal fluid PAG levels and pH.  相似文献   
94.
OBJECTIVE: To investigate renal function in clinically normal dogs when awake and during anesthesia with medetomidine; xylazine, ketamine, and halothane (XKH) combination; or propofol. ANIMALS: 10 adult female Beagles. PROCEDURES: At intervals of 15 days, dogs were administered medetomidine (0.05 mg/kg, IV); XKH combination (xylazine [1 mg/kg, IV], ketamine [5 mg/kg, IV], and halothane [1% end-tidal concentration]); or propofol (6 mg/kg, IV) to induce anesthesia or no treatment. Glomerular filtration rate was assessed on the basis of renal uptake (RU; determined via renal scintigraphy) and plasma clearance (CL) of technetium 99m-labeled diethylenetriamine pentaacetic acid ((99m)Tc-DTPA). RESULTS: In awake dogs, mean +/- SEM RU was 9.7 +/- 0.4% and CL was 3.86 +/- 0.23 mL/min/ kg. Renal uptake and CL of (99m)Tc-DTPA were not significantly modified by administration of XKH (RU, 11.4 +/- 0.9%; CL, 4.6 +/- 0.32 mL/min/kg) or propofol (RU, 9.7 +/- 0.3%; CL, 3.78 +/- 0.37 mL/min/kg). Half-life elimination time of plasma (99m)Tc-DTPA decreased significantly in XKH-anesthetized dogs, compared with the value in awake dogs (14.4 minutes and 28.9 minutes, respectively). However, glomerular filtration rate was significantly decreased by administration of medetomidine (RU, 3.9 +/- 0.1%), and the time to maximum kidney activity was significantly increased (867 +/- 56 seconds vs 181 +/- 11 seconds without anesthesia). CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that anesthesia with propofol or an XKH combination did not alter renal function in healthy Beagles, but anesthesia with medetomidine decreased early RU of (99m)Tc-DTPA.  相似文献   
95.
A 4.5-month-old, male domestic shorthair was presented with bilateral femoral fractures after falling from a low height. Radiographs revealed reduced radio-opacity and thin cortices of all long bones. A presumptive diagnosis of osteodystrophy, secondary to osteogenesis imperfecta, was made on postmortem examination.  相似文献   
96.
REASONS FOR PERFORMING STUDY: Lameness has often been suggested to result in altered movement of the back, but there are no detailed studies describing such a relationship in quantitative terms. OBJECTIVES: To quantify the effect of induced subtle forelimb lameness on thoracolumbar kinematics in the horse. METHODS: Kinematics of 6 riding horses was measured at walk and at trot on a treadmill before and after the induction of reversible forelimb lameness grade 2 (AAEP scale 1-5). Ground reaction forces (GRF) for individual limbs were calculated from kinematics. RESULTS: The horses significantly unloaded the painful limb by 11.5% at trot, while unloading at walk was not significant. The overall flexion-extension range of back motion decreased on average by 0.2 degrees at walk and increased by 3.3 degrees at trot (P<0.05). Changes in angular motion patterns of vertebral joints were noted only at trot, with an increase in flexion of 0.9 degrees at T10 (i.e. angle between T6, T10 and T13) during the stance phase of the sound diagonal and an increase in extension of the thoracolumbar area during stance of the lame diagonal (0.7degrees at T13, 0.8 degres at T17, 0.5 degres at L1, 0.4 degrees at L3 and 0.3 degrees at L5) (P<0.05). Lameness further caused a lateral bending of the cranial thoracic vertebral column towards the lame side (1.3 degrees at T10 and 0.9 degrees at T13) (P<0.05) during stance of the lame diagonal. CONCLUSIONS: Both range of motion and vertebral angular motion patterns are affected by subtle forelimb lameness. At walk, the effect is minimal, at trot the horses increased the vertebral range of motion and changed the pattern of thoracolumbar motion in the sagittal and horizontal planes, presumably in an attempt to move the centre of gravity away from the lame side and reduce the force on the affected limb. POTENTIAL RELEVANCE: Subtle forelimb lameness affects thoracolumbar kinematics. Future studies should aim at elucidating whether the altered movement patterns lead to back and/or neck dysfunction in the case of chronic lameness.  相似文献   
97.
A field trial was conducted to study Mycoplasma hyopneumoniae (Mh) infection dynamics by nested polymerase chain reaction (nPCR) and serology in pigs of a farm affected by enzootic pneumonia (EP). Moreover, correlation of Mh detection at different respiratory tract sites with presence of EP gross and microscopic lung lesions was assessed. These parameters were studied and compared between vaccinated (two doses at 1 and 3 weeks of age versus one dose at 6 weeks of age) and non-vaccinated pigs. Animals were monitored from birth to slaughter by nPCR from nasal swabs and by serology. From 3 to 22 weeks of age, an average of three pigs per treatment and per batch were necropsied (n = 302). The remaining pigs were sent to the slaughter (n = 103). Nasal, bronchial and tonsillar swabs were taken from the necropsied/slaughtered pigs; gross and microscopic EP-suggestive lung lesions were also assessed. Single and double vaccination resulted in earlier seroconversion and higher percentage of Mh seropositive pigs compared to control group. At slaughter, double vaccinated pigs showed lower percentage of EP-compatible gross lung lesions and lower Mh prevalence at upper respiratory tract sites (nasal cavity and tonsil) than control pigs.  相似文献   
98.
99.
Chorioptes sp. mite infestation is increasingly recognized as a cause of skin disease in New World camelids and there is a need for an effective treatment protocol to eliminate herd infestation. In this field trial, eprinomectin applied topically at the rate of 0.5 mg kg(-1) weekly for 10 weeks was found to be ineffective in a herd of 12 llamas and 16 alpacas.  相似文献   
100.
An orbital sialocele developed in a dog following enucleation for protracted glaucoma. This eye had historically been treated for keratoconjunctivitis sicca by parotid duct transposition approximately 5 years previously, and the duct was ligated distally at the time of enucleation. One month following enucleation, the dog presented with a fluctuant conical-shaped swelling ventrolateral to the orbital socket. Surgical exploration revealed a dilated, fibrotic distal portion of the previously transposed parotid duct, and saliva, within the enucleated orbit. The distal portion of the duct and saliva-containing tissues from within the orbit were excised. The remaining proximal normal portion of the parotid duct was re-routed into the oral cavity. Clinicopathologic and histologic examination of the excised orbital contents and dilated portion of duct revealed a sterile sample of saliva and moderate chronic periductal fibrosis. At a 6-month re-evaluation there was no evidence of recurrence of the sialocele, and the parotid duct was functional.  相似文献   
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