Leptin is a small peptide hormone (16-kDa protein) that is mainly, but not exclusively, produced in adipose tissue. The circulating leptin concentration therefore directly reflects the amount of body fat.
is many evidences supporting the statement that changes in insulin secretion and glucose metabolism are the major mediators of leptin production by adipose tissue .
but not article this hormone affect on Hematological Parameters
Regarding the issue of LEPTIN, (adipose tissue hormone);
It may be considered as a "switch" for the initiation of the reproductive cycle that would indicate the 'efficiency' of body energy reserves.
It informs the endocrinological system (hypothalamus) of the brain so that a new cascade of hormonal release (mainly the LH) could occur in the bloodstream.
In our evidence-based studies, both leptin and IGF-I seem positively correlated with the LH in ewe-lambs. Further, leptin has a positive correlation with the BCS (Yildiz et al, 2008; Cenesiz et al., 2009). For details, please see the links below:
Article Tanniniferous Oak (Quercus hartwissiana) Leaves Do Not Affec...
Conference Paper Interrelationships Between Body Condition Score, Leptin and ...
Collectively, we may consider that leptin would be critically important for reproduction, especially for candidate mother animals with poor body conditions (BCS). Apparently, the higher the BCS the more the lambs (twins) are born (Yildiz, 2002; Ucar et al., 2005), as detailed below:
Article Effects of Sexually Activated Rams or Ewes on Pulsatile LH S...
Article Effect of Progestagen/PMSG Treatment for Oestrus Synchroniza...