Recently, evaluation of the serum levels of anterior pituitary hormones (thyroid stimulating hormone, follicle stimulating hormone, luteinizing hormone, and prolactin) and detection of electrolyte imbalances (hyponatremia, hypochloremia, hypokalemia) have been proposed as useful adjuncts to enhance the presumptive diagnosis of PAS in ruminants with neurological signs [11,14]. The gene discussed is PRL; the disease is Hyponatremia.