Blood Volume of Geese Treated With Androgen and Estrogen ,

Hematological changes associated with egg production: estrogen dependence and repeatability

“…However, similar differential effects on estrogendependent reproductive traits have been documented here and in previous studies: tamoxifen treatment causes a robust decrease in egg size (Williams, 2000;Williams, 2001;Wagner and Williams, 2007), whereas exogenous estradiol does not increase egg size (Christians and Williams, 1999;Williams, 1999). Although previous studies have reported that estradiol treatment induces anemia (range -2 to -15%) in domestic fowl (Domm and Taber, 1946;Sturkie and Eiel, 1966), pilgrim geese (Hunsaker, 1968), Japanese quail (Nirmalan and Robinson, 1972;Nirmalan and Robinson, 1973;Garcia et al, 1984), rain quail (Deshmukh and Suryawanshi, 1982) and white-crowned sparrows (Kern et al, 1972), these studies all used non-breeding birds, which would have low baseline levels of endogenous estrogens. To our knowledge, our study is the first to assess effects of physiological levels of estradiol on hematological parameters in laying females specifically within the context of egg production.…”

Blood: Physical Characteristics, Formed Elements, Hemoglobin, and Coagulation

“…However, with continued estrogen administration erythropoiesis is not depressed in chickens (Gilbert, 1963). Although estrogen depressed erythrocyte volume in geese, androgen had no significant effect (Hunsaker, 1968). Some have reported levels of hemoglobin lower in laying than in nonlaying chickens but others have reported no difference (see Bell and Sturkie, 1965); however, no attempts have been made to relate these alleged differences to estrogen levels.…”

“…Although Hunsaker (1968) reported that estrogen depressed erythropoiesis in geese, androgen had little or no effect on red cell counts of normal male and females, and castrate male and female geese.…”