Photoperiodic effects on serum glucocorticoids and fur growth in mink Public Deposited

http://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/rn301460t

Descriptions

Attribute NameValues
Creator
Abstract or Summary
  • The relationship of glucocorticoid secretion to light-induced, early-winter priming of pelage in ranch mink was investigated. Sixteen Standard Dark, mature, female mink were exposed to natural light conditions of 45° North latitude beginning on December 13, 1977. A 2x4 cm area of the right hip of each animal was sheared permitting measurement of changes in fur growth. At biweekly intervals blood samples were obtained by cardiac puncture and the length and width of the vulva measured. On June 26, 1978 the remaining animals were assigned at random to two groups and an additional five animals were placed in each group (total, eight animals per group). Group I animals were housed in a light-control facility and subjected to 6 hours of artificial light daily from June 26 to November 27, 1978. Group 11 animals served as controls and were exposed to natural light conditions. Blood samples, fur and vulva measurements continued to be collected biweekly. Serum concentrations of total glucocorticoids were determined by competitive protein binding. Changes in the pelage of mink reared under natural light conditions were typical. The pelage of mink reared under reduced lighting was fully prime by October 30, as compared with the pelage of control animals which was prime by November 27 (time x light regime interaction, P<.01). A significant seasonal effect (P<.01) on serum total glucocorticoid levels in control mink revealed a pattern of three peaks over the 12-month period. The pattern of glucocorticoid secretion was not affected by exposure of mink to reduced lighting. Maximal concentrations of serum total glucocorticoids occurred on the same date (September 5) in both groups although levels were greater in the light-treated (44.5 + 10.4 ng/ml) than in the control mink (26.9 + 5.7 ng/ml). Fur growth was found to be positively correlated with serum total glucocorticoid concentrations in both light-treated and control animals during the period from June 26 to December 21, 1978 (overall r = .14, P<.05). Both the length and width of the vulva increased (P<.01) between February 21 and March 20 in animals reared under natural lighting. No changes were observed in the size of the vulva in control or light-treated mink during the remainder of the year. These data suggest that some light-induced factor acts alone or in concert with glucocorticoids to promote pelage changes in the mink.
Resource Type
Date Available
Date Copyright
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome) using ScandAll PRO 1.8.1 on a Fi-6670 in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces
Additional Information
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2013-09-12T17:35:48Z (GMT) No. of bitstreams: 1 WeissDeborahE1980.pdf: 204995 bytes, checksum: ac65c3dc8c3e5d88962f0118f4ce2245 (MD5)
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2013-09-11T19:24:12Z (GMT) No. of bitstreams: 1 WeissDeborahE1980.pdf: 204995 bytes, checksum: ac65c3dc8c3e5d88962f0118f4ce2245 (MD5)
  • description.provenance : Made available in DSpace on 2013-09-12T17:35:48Z (GMT). No. of bitstreams: 1 WeissDeborahE1980.pdf: 204995 bytes, checksum: ac65c3dc8c3e5d88962f0118f4ce2245 (MD5) Previous issue date: 1979-08-24
  • description.provenance : Submitted by Katy Davis (kdscannerosu@gmail.com) on 2013-09-11T17:45:28Z No. of bitstreams: 1 WeissDeborahE1980.pdf: 204995 bytes, checksum: ac65c3dc8c3e5d88962f0118f4ce2245 (MD5)

Relationships

Parents:

This work has no parents.

Last modified

Downloadable Content

Download PDF

Items