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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine effects of atracurium on intraocular pressure (IOP), eye position, and arterial blood pressure in eucapnic and hypocapnic dogs anesthetized with isoflurane.

Animals—16 dogs.

Procedure—Ventilation during anesthesia was controlled to maintain PaCO2 at 38 to 44 mm Hg in group-I dogs (n = 8) and 26 to 32 mm Hg in group-II dogs (8). Baseline measurements for IOP, systolic, diastolic, and mean arterial blood pressure, central venous pressure (CVP), and heart rate (HR) were recorded. Responses to peroneal nerve stimulation were monitored by use of a force-displacement transducer. Atracurium (0.2 mg/kg) was administered IV and measurements were repeated at 1, 2, 3, and 5 minutes and at 5-minute intervals thereafter for 60 minutes.

Results—Atracurium did not affect IOP, HR, or CVP. Group II had higher CVP than group I, but IOP was not different. There was no immediate effect of atracurium on arterial blood pressure. Arterial blood pressure increased gradually over time in both groups. Thirty seconds after administration of atracurium, the eye rotated from a ventromedial position to a central position and remained centrally positioned until 100% recovery of a train-of-four twitch response. The time to 100% recovery was 53.1 ± 5.3 minutes for group I and 46.3 ± 9.2 minutes for group II.

Conclusions and Clinical Relevance—Atracurium did not affect IOP or arterial blood pressure in isoflurane- anesthetized dogs. Hyperventilation did not affect IOP or the duration of effect of atracurium. (Am J Vet Res 2004;65:179–182)

Full access
in American Journal of Veterinary Research

SUMMARY

Protein concentration was determined, using the Bradford technique, in tears from cats with normal corneas and from cats with corneal sequestrum. Tears from the former group contained 5.81 ± 2.29 mg of protein/ml; those from corneal sequestrum-affected cats contained 6.21 ± 2.21 mg/ml. Difference between the 2 values was not significant. Molecular weight determination was made, using 4 to 20% sodium dodecyl sulfate-polyacrylamide gels. Molecular mass of proteins ranged from 263 to 14 kDa. There was no detectable difference in the band patterns for the 2 groups.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To measure ocular effects (blood-aqueous barrier breakdown and intraocular pressure [IOP]) following aqueocentesis performed with needles of various sizes in dogs.

Animals—28 healthy adult dogs.

Procedures—24 dogs underwent unilateral aqueocentesis (24 treated eyes and 24 contra-lateral untreated eyes); 25-, 27-, or 30-gauge needles were used in 3 treatment groups (n = 8/group). Four dogs were untreated controls. Aqueocentesis was performed during sedation and topical anesthesia. Anterior chamber fluorophotometry was performed before and after aqueocentesis on day 1. On days 2 through 5, sedation and fluorophotometry were repeated. Intraocular pressure was measured with a rebound tonometer at multiple time points.

Results—Aqueocentesis resulted in blood-aqueous barrier breakdown detected via fluorophotometry in all treated eyes, with barrier reestablishment by day 5. On day 2, the contralateral untreated eyes of all 3 groups also had significantly increased fluorescence. Use of a 25-gauge needle resulted in a significant increase in treated eyes' anterior chamber fluorescence on days 3 and 5 as well as a significant increase in IOP 20 minutes following aqueocentesis, compared with the other treatment groups.

Conclusions and Clinical Relevance—Aqueocentesis performed with a 25-gauge needle resulted in the greatest degree of blood-aqueous barrier breakdown and a brief state of intraocular hypertension. Use of a 27- or 30-gauge needle is recommended for aqueous paracentesis. A consensual ocular reaction appeared to occur in dogs following unilateral traumatic blood-aqueous barrier breakdown and may be of clinical importance.

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in American Journal of Veterinary Research

Summary

Conjunctival swab specimens from healthy pigs were cultured to determine normal microbial population. Four commercial swine operations were selected for study. Pigs of 4 age groups were tested: nursing pigs, nursery pigs, feeder pigs, and sows. Swab specimens were taken from the conjunctival sac of each pig. Bacterial, fungal, and mycoplasmal growth was determined separately. Chlamydia sp was detected by use of an elisa. Bacteria were recovered from 98% of specimens evaluated. α-Streptococcus sp (89%) was the most commonly recovered organism, followed by Staphylococcus epidermidis (39%) and Staphylococcus sp (39%). Mycoplasma sp was not detected in any of the specimens. Chlamydia sp was identified in 28% of all specimens evaluated. These results are similar to reports of normal conjunctival flora in other domestic animals.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate lactoferrin and lysozyme content in various ocular glands of bison and cattle and in tears of bison.

Sample Population—Tissues of ocular glands obtained from 15 bison and 15 cattle and tears collected from 38 bison.

Procedure—Immunohistochemical analysis was used to detect lysozyme and lactoferrin in formalin-fixed, paraffin-embedded sections of the ocular glands. Protein gel electrophoresis was used to analyze ocular glands and pooled bison tears by use of a tris-glycine gel and SDS-PAGE. Western blotting was used to detect lactoferrin and lysozyme.

Results—Immunohistochemical staining for lactoferrin was evident in the lacrimal gland and gland of the third eyelid in cattle and bison and the deep gland of the third eyelid (Harder's gland) in cattle. Equivocal staining for lactoferrin was seen for the Harder's gland in bison. An 80-kd band (lactoferrin) was detected via electrophoresis and western blots in the lacrimal gland and gland of the third eyelid in cattle and bison, Harder's glands of cattle, and bison tears. An inconsistent band was seen in Harder's glands of bison. Lysozyme was not detected in the lacrimal gland of cattle or bison with the use of immunohistochemical analysis or western blots. Western blots of bison tears did not reveal lysozyme.

Conclusion and Clinical Relevance—Distribution of lactoferrin and a lack of lysozyme are similar in the lacrimal gland of cattle and bison. Differences in other tear components may be responsible for variability in the susceptibility to infectious corneal diseases that exists between bison and cattle. (Am J Vet Res 2003;64:104–108)

Full access
in American Journal of Veterinary Research

Objective

To establish ocular characteristics, determine nature and prevalence of ocular lesions, and identify representative bacterial flora from the conjunctiva of North American bison (Bison bison).

Design

Prospective study.

Animals

63 bison; 45 males and 18 females.

Procedure

Ophthalmic examinations were performed on 1 group of 38 bison in December 1997 and on a second group of 25 in March 1998. Eyes were examined with a penlight, magnification loop, and indirect ophthalmoscope. Two culture swabs were used to obtain samples from the inferior conjunctival sac. One swab was submitted for isolation of bacteria and the second was submitted for isolation of Mycoplasma organisms.

Results

15 ocular abnormalities were observed in 13 of the 63 bison. These included minor ocular discharge in 5 animals, 1 eyelid laceration, 1 periocular Demodex spp infection, 6 corneal abnormalities, 1 anterior synechia, and 1 cataract. Seventeen species of bacteria were isolated from the 63 swabs submitted for culture. The most prevalent bacteria were of the genus Bacillus (74.6%). Mycoplasma organisms were not observed.

Conclusions and Clinical Relevance

Corneal abnormalities were the most frequently identified ocular lesions in bison. Bacterial flora of the conjunctiva and ocular characteristics were similar to those reported for cattle. (J Am Vet Med Assoc 1999;215:1142–1144)

Free access
in Journal of the American Veterinary Medical Association