Effect of Topical 1% Cyclopentolate Hydrochloride on Tear Production, Intraocular Pressure, and Pupil Size in Healthy Turkman Horses.

This study was performed to evaluate the effect of topical 1% cyclopentolate hydrochloride on tear production (STT), intraocular pressure (IOP), and vertical pupil diameter (VPD) in healthy Turkman horses. Forty eyes of 20 clinically normal horses were used for this study, which were randomly assigned to two groups. Before instillation of 1% cyclopentolate, the baseline STT, IOP, and VPD of each group were recorded. Then, one drop of cyclopentolate was instilled randomly into one eye of each animal, and the contralateral eye served as control. Measurements were repeated at 20 minutes, 60 minutes, 90 minutes, 120 minutes, 12 hours, and 24 hours, and every 24 hours up to 120 hours post drug instillation in all animals. There was no significant effect on STT over the time course measured in both the treated and untreated eyes of the treatment groups after unilateral instillation of 1% cyclopentolate when compared to baseline values. A significant increase in the IOP was observed after 20 minutes, which persisted for more than 90 minutes; then, the IOP insignificantly decreased below the baseline values after 120 minutes. Maximum VPD was recognized at 12 hours post instillation in treated eyes (15.8 ± 2.3 mm), which was significantly different in comparison to the baseline (P = .07). Cyclopentolate could be considered as a long term and potent cycloplegic drug in horses when taking into account the possible side effect of atropine.

Strip meniscometry in dogs, cats, and rabbits.

OBJECTIVE: The purpose of this study was to establish the normal values of strip meniscometry (SM) as a lacrimal function test and to compare the results with Schirmer tear test I (STT I) in dogs, cats, and rabbits. ANIMALS STUDIED: Sixty healthy adult dogs from twelve different breeds (120 eyes), twenty adult healthy domestic shorthair cats (40 eyes) and eighteen adult healthy New Zealand white rabbits (36 eyes) were used in this study. PROCEDURES: Lacrimal function was tested by SM tube in all animals. After 24 h at the same time of day, tear production was measured using STT I. RESULTS: Mean SM and STT I values for all of the dogs, cats, and rabbits were 9.66 ± 2.15 mm/5 s and 15.10 ± 3.06 mm/min; 10.50 ± 0.7 mm/5 s and 11.00 ± 1.41 mm/min; 4.72 ± 1.20 mm/5 s and 4.22 ± 2.47 mm/min, respectively. There was a correlation (r = 0.281; P = 0.018) between SM and STT I values in dogs, but no correlation was observed in cats and rabbits (P = 0.61, P = 0.06). No correlation was found between age of animals and obtained SM values in each species (P > 0.29). Sex had no effect on SM values in each species (P > 0.08). CONCLUSIONS: The result of this study provided the normal clinical values of strip meniscometry as lacrimal function test in three species.

Measurement of tear production and intraocular pressure in ducks and geese.

OBJECTIVES: The purpose of this study was to establish a reference value of tear production and intraocular pressure in clinically normal ducks and geese. ANIMAL STUDIED: The study population consisted of forty-eight ducks (24 males and 24 females) and fifty-two geese (26 males and 26 females). PROCEDURES: Birds were gently physically restrained in dorsoventral position without any pressure to the head and neck. Tear secretion and intraocular pressure were measured using 5-mm-wide Schirmer tear test strips and TonoVet® rebound tonometer, respectively. RESULTS: Overall mean ± 2SD STT and IOP values of all eyes were 6.2 ± 2.2 mm/min and 10.2 ± 2.2 mmHg, respectively, for the ducks; 5.5 ± 2.6 mm/min and 9.1 ± 2.0 mmHg, respectively, for the geese. There was no statistically significant difference in IOP between left eye and right eye or between males and females in ducks (P = 0.56, P = 0.63) and geese (P = 0.23, P = 0.22). Analysis of variance revealed that there were no significant differences in the STT and IOP between the breeds in ducks (P = 0.49, P = 0.68) and geese (P = 0.14, P = 0.26). CONCLUSIONS: Results of this study may be beneficial for the diagnosis and therapeutic monitoring of ducks and geese affected with Keratoconjunctivitis sicca, glaucoma, and uveitis.

MEASUREMENT OF INTRAOCULAR PRESSURE IN THE DOMESTIC PIGEON (COLUMBIA LIVIA).

The purpose of this study was to establish intraocular pressure values in clinically normal pigeons. One hundred (52 male and 48 female) healthy pigeons ( Columbia livia ) of six different breeds, ranging in age from 20 to 51 mo were used in the study. Pigeons were gently physically restrained in a dorsoventral position without any pressure or extension to the head and neck. A rebound tonometer with a disposable probe was held horizontally and 4-5 mm from the central corneal surface. Calibration of the device was set to "P." Overall, the mean ± SD intraocular pressure values of all eyes were 6.1 ± 0.9 mmHg (ranging from 3 to 9 mmHg). Mean ± SD values for left and right eyes were 6.1 ± 1.0 and 6.0 ± 1.2 mmHg, respectively. There was no statistically significant difference in IOP between the left eye and right eye or between males and females (P = 0.49; P = 0.74). Analysis of variance revealed that there were no significant differences in the IOP between the breeds (P = 0.22).

Twenty-four-Hour Measurement of Intraocular Pressure in Guinea Pigs (Cavia porcellus).

The objective of this study was to measure intraocular pressure (IOP) in intact, healthy guinea pigs (15 male, 15 female) every 2 h for a 24-h period. First, IOP was measured by using rebound tonometry (RBT). After a 1-min rest period, 0.5% proparacaine ophthalmic solution, a topical anesthetic, was applied to both eyes; 4 min after anesthetic instillation, IOP was measured by using applanation tonometry (APT). The IOP was lower during the light period (0700 to 1900) than during the dark phase (2000 to 0600). The lowest IOP by both RBT and APT (3.68 and 13.37 mm Hg, respectively) occurred at 0700, whereas maximal IOP occurred at 2300 for RBT (8.12 mm Hg) but at 2100 for APT (20.62 mm Hg). No significant differences in IOP between the left and right eyes or between RBT and APT were noted. In addition, daily variations in the IOP of guinea pigs seem to be independent of sex and body weight. The results of this study may be beneficial in the diagnosis and observation of glaucoma in guinea pigs.

Measurement of Tear Production and Intraocular Pressure in Healthy Captive Helmeted Guinea Fowl ( Numida meleagris ).

We establish reference values of tear production by the phenol red thread test (PRTT) and intraocular pressure (IOP) by rebound tonometry in helmeted guinea fowl ( Numida meleagris ). Aqueous tear production and IOP were measured in 44 (22 males, 22 females) clinically normal captive helmeted guinea fowl. Birds were gently physically restrained in the sitting position without any pressure to the head or neck. In each bird, aqueous tear production was measured by placing phenol red threads in the superior conjunctival fornix, and IOP was measured by using a Tonovet rebound tonometer. Overall mean ± standard deviation (SD) values of PRTT and IOP of all eyes were 16.5 ± 1.3 mm/15 s (ranging from 14-18 mm/15 s) and 9.1 ± 0.9 mm Hg (ranging from 7-10 mm Hg), respectively. No significant differences were found in IOP or PRTT between males and females (P = .76; P = .83, respectively) or between the left and right eyes (P = .34 and .66, respectively) in the guinea fowl. Results of this study may be beneficial for the diagnosis and therapy of keratoconjunctivitis sicca, glaucoma, and uveitis in helmeted guinea fowl.

Seroprevalence and Risk Factors of Ehrlichia canis Infection among Companion Dogs of Mashhad, North East of Iran, 2009-2010.

BACKGROUND: The aims of this study were to determine the seroprevalence of canine ehrlichiosis and risk factors of this disease in companion dogs' population of Mashhad, North East of Iran. Canine Monocytic Ehrlichiosis (CME) is a zoonotic disease transmitted by ticks, Rhipicephalus sanguineus, and caused by an obligate intracellular bacterium, Ehrlichia canis. METHODS: During September 2009 until November 2010, 250 companion dogs from Mashhad, North-East of Iran, were examined for serum antibody detection against E. canis by means of immunofluorescence assay test (IFAT) and factors associated with a positive antibody response. RESULTS: There was a very low prevalence of anti-E. canis antibodies (0.8%, 2/250) among studied dogs. The antibody titers for two seropositive dogs were 1:80 and 1:160, respectively. One (0.4%) of seropositive dogs was infested with, R. sanguineus. In blood smears from one of infested dogs (0.4%), typical morulae of E. canis was observed in lymphocytes. The results confirm that the lowest occurrence of reactive dogs indoors probably related to low tick infestion. CONCLUSION: This is the first report that describes serological evidences of canine monocytic ehrlichiosis in North-East of Iran. Results suggested that E. canis infection in owned pet dogs from North of Khorasan was not endemic from 2009 to 2010. Additional molecular studies are necessary to confirm E. canis infection and to identify the local strains of the organism.

MEASUREMENT OF INTRAOCULAR PRESSURE USING TONOVET® IN EUROPEAN POND TURTLE (EMYS ORBICULARIS).

Twenty-two captive adult European pond turtles (12 males and 10 females) were unrestrained without sedation while intraocular pressure (IOP) was measured by means of a Tonovet®. Mean±SD IOP values between 8 and 10 am for all turtles were 5.42±0.96 mm Hg (range, 3-9 mm Hg). IOP between the right and left eye and between males and females was not significantly different. There was no correlation between IOP and body weight or body length of animals.

Effects of short-term oral administration of trimethoprim-sulfamethoxazole on tear production in clinically normal Syrian hamsters.

OBJECTIVE: To determine effects of 14 days of oral administration of trimethoprim-sulfamethoxazole on aqueous tear production in clinically normal Syrian hamsters. ANIMAL STUDIED: Fifteen healthy adult Syrian hamsters. PROCEDURE: Baseline phenol red thread test (PRTT) values were recorded 1 day prior to treatment. Eight hamsters in treated group received 15 mg/kg trimethoprim-sulfamethoxazole orally twice a day for 14 days. The remaining seven hamsters were used as untreated controls and received a placebo. All ophthalmic tests were performed without chemical restraint. PRTT values were evaluated in both eyes of all Syrian hamsters using a commercial PRTT strip of a single lot number. RESULTS: The mean ± SD baseline PRTT values for treatment group and control group were 7.25 ± 1.3 mm/15 s and 5.42 ± 1.13 mm/15 s, respectively. After 14 days of drug administration, the mean ± SD PRTT values for treatment group and control group were 5.62 ± 1.5 and 5.64 ± 0.74, respectively. Significant decreases in the PRTT values, compared with baseline values, were observed in the treatment group on day 15 (P = 0.042). CONCLUSIONS: Trimethoprim-sulfamethoxazole decreased tear production in the hamster in this study.