title: Determination of Schirmer tear test-1 values in clinically normal alpacas (Vicugña pacos) in North America.
abstract: OBJECTIVE
  To determine the normal reference range for Schirmer tear test-1 (STT-1) values in eyes of healthy alpacas (Vicugña pacos).
  
  
  METHODS
  Complete ophthalmic examinations were performed on forty healthy alpacas (80 eyes). STT-1 values were obtained in both eyes of all alpacas using a commercial STT strip of a single lot number. Data were analyzed, using a doubly repeated measures ANOVA design, Student's paired t-test, and Pearson correlation test, with P ≤ 0.05 considered significant.
  
  
  RESULTS
  The STT-1 values ± standard deviation (SD) were 20.80 ± 4.01 mm/min OD, 20.00 ± 4.13 mm/min OS, and 20.88 ± 4.04 mm/min OU (range 15.50-30.50 mm/min). No significant differences in STT-1 were found between OD and OS. STT-1 was not significantly affected by breed. Schirmer tear test-1 values were significantly increased by 3.45 mm/min for every 10 year increase in age.
  
  
  CONCLUSIONS
  This study provides a reference range of STT-1 in the healthy alpaca which can assist veterinarians in diagnosing potential keratoconjunctivitis sicca, tear film abnormalities, as well as ocular surface diseases in alpacas.
authors.affiliation: Eye Care for Animals, 1021 E. 3300 S., Salt Lake City, UT, 84106, USA.
authors.forename: Jessica E
authors.identifier: http://orcid.org/0000-0002-0731-717X
authors.initials: JE
authors.lastname: McDonald
authors.affiliation: Eye Care for Animals, 1021 E. 3300 S., Salt Lake City, UT, 84106, USA.
authors.forename: Amy M
authors.initials: AM
authors.lastname: Knollinger
authors.affiliation: Eye Care for Animals, 12419 Metric Blvd, Austin, TX, 78758, USA.
authors.forename: Darryl D
authors.initials: DD
authors.lastname: Dees
authors.affiliation: Eye Care for Animals, 1021 E. 3300 S., Salt Lake City, UT, 84106, USA.
authors.forename: Nicole E
authors.initials: NE
authors.lastname: MacLaren
mesh_terms: D000818:Animals; D002161:Camelids, New World / Q000502:physiology*; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D008297:Male; D012016:Reference Values; D013666:Tears / Q000502:physiology*
keywords: Schirmer tear test; alpaca; camelids; keratoconjunctivitis sicca; tear film; tear production