HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Moore, L. A. Search for Related Content PubMed Articles by Moore, L. A.

Some Ocular Changes and Deficiency Manifestations in Mature Cows Fed a Ration Deficient in Vitamin A^*

Dairy Department, Michigan Agricultural Experiment Station, East Lansing

ABSTRACT

1. Mature cows on a vitamin A deficient ration failed to develop blindness due to constriction of the optic nerve' such as has been reported in calves.
   
2. A definite papilledema failed to develop in two cows out of six in these experiments. Once the papilledema develops it takes considerable time for it to recede.
   
3. Mature cows did develop nyctalopia, incoordination, and an edema of the legs on the A deficient ration.
   
4. The tapetum nigrum and lucidum developed a mottled appearance.
   
5. When the plasma carotene values receded to a 0.2 to 0.5 microgram level deficiency symptoms usually followed in a short period of time.
   
6. The fat of a Guernsey cow which died with symptoms of vitamin A deficiency showed the presence of a pigment which was most likely carotene since it was epiphasic between petroleum ether and 92 per cent methyl alcohol.
   

^* Journal Article 532 (n. s.).

¹ Now at the University of Maryland.