title: Circannual variations of the bleeding time in the rat.
abstract: This study was carried out to determine the annual fluctuations of the tail bleeding time in the rat. Bleeding time was determined by transection of the tail of pentobarbital-anesthetized rats. Over a 6-year period, monthly measurement of the tail bleeding time revealed highly reproducible circannual fluctuations. Bleeding times were shortened in the summer (414 +/- 18 s in July), being almost half that observed during the winter span (886 +/- 32 s in January). The difference between these two time points was highly significant (p < 0.001). This study reports for the first time circannual variations of the bleeding time in the rat.
authors.affiliation: Sanofi Recherche, Haemobiology Research Department, Toulouse, France.
authors.forename: A
authors.initials: A
authors.lastname: Bernat
authors.forename: J P
authors.initials: JP
authors.lastname: Maffrand
authors.forename: J M
authors.initials: JM
authors.lastname: Herbert
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001760:Bleeding Time; D008297:Male; D010507:Periodicity; D051381:Rats; D017207:Rats, Sprague-Dawley / Q000097:blood*; D012621:Seasons