Effects of active, inactive and compounded Saccharomyces cerevisiae on growth-related hormones and performance of Japanese quails (Coturnix Japonica)
The objective of this research was to determine the effects of active, inactive and compounded Saccharomyces cerevisiae (SC) as natural feed additives on growth performance, visceral organs weight, insulin, thyroxin and growth hormone of Japanese quails. One day old Japanese quails allocated in 4 treatments by 4 replicates and 12 birds per pen. The experimental diets consisted of a basal diet without additive (Control), 1 g/kg active SC (ASC) as a probiotic, 1 g/kg inactive SC (ISC) as a prebiotic and mixed of 0.5 g/kg active + 0.5 g/kg inactive SC (ASC+ISC) as a synbiotic added to the basal diet. At 42 days, growth performance values were calculated, then eight birds were weighted and slaughtered for visceral organs weight recording, and blood sampling were taken for analysis of serum hormones using ELISA technique. Consumption of each ASC and ISC caused elevation in feed intake and body weight and better feed conversion (p < 0.05). The dressing percentage in quails fed three types of each additive was increased (p < 0.05). Total viscera weight in males fed each additives was declined (p < 0.05). In females, the weight of total viscera fed ASC + ISC was higher than ASC fed group (p < 0.05). Consumption of ISC in males and ASC in females caused to depressing in proventriculus weight (p < 0.05). The gizzard weight in males fed ASC and ISC were decreased and in females fed ASC and ASC + ISC were elevated (p < 0.05). Females fed ASC have lighter intestines weight than control group (p < 0.05). The heart weight in males fed ASC and ISC and in females fed ISC were reduced (p < 0.05). In males fed ASC + ISC liver weight was lighter than other groups and in ASC and ISC fed groups lighter than control group (p < 0.05). In females fed ASC + ISC liver weight was reduced (p < 0.05). Consumption of ISC in males and ASC + ISC in females caused insulin elevation (p < 0.05). Growth hormone level was elevated by inclusion of ASC + ISC in basal diet of both genders (p < 0.05). It was concluded that consumption of S. cerevisiae in different form of activity could be used in quail's diet to improve growth performance values by increasing the feed intake and stimulating the insulin and growth hormone release and they also have implications in human health by organic meat and egg production.
Key words: Saccharomyces cerevisiae, hormone, growth performance, quail.