Growth performance, haemo-biochemical parameters and meat quality characteristics of male Japanese quails fed a Lippia javanica-based diet
A total of 105 male Japanese quails (153.2 ± 10.21 g) (Cortunix cortunix japonica) were reared in an environmentally controlled house to investigate the effect of inclusion of Lippia javanica leaf meal on growth performance, haematological and serum biochemical parameters, and carcass and meat quality characteristics. The quails were randomly allocated to 15 pens, with each pen holding 7 quails. Pens were then randomly allocated to the following experimental diets: 1) commercial grower diet without antibiotics [NegCon]; 2) commercial grower diet with antibiotics, coxistac and olaquindox [PosCon]; and 3) commercial grower diet without antibiotics in which L. javanica was included at the rate of 25 g/kg [Ljav25]. Experimental diets and fresh water were offered ad libitum. Weekly feed intake and body weights were recorded to calculate feed conversion efficiency (FCE). At 9 weeks of age, quails were slaughtered at a local poultry abattoir for assessment of blood parameters, carcass and meat quality characteristics. Repeated measures analysis showed no significant week × diet interaction effect on average weekly feed intake (AWFI), average weekly weight gain (AWG) and FCE. Diet had no significant influence on AWFI, AWG, FCE, and haematological parameters. There was no dietary effect on overall FI, overall WG and overall FCE. Alanine transaminase (ALT) was the only serum biochemical parameter influenced by diet. Quails offered Ljav25 had higher ALT content (56.83 u/L) than those offered PosCon (18.0 u/L). Diets had no significant impact on carcass characteristics and internal organs, except for gizzard weights. Immediately after slaughter, diets caused no effect on meat quality parameters, except meat lightness (L*), whereas at 24 h post slaughter, diets had significant impact on meat yellowness (b*). No dietary variation was observed for peak positive force (PPF) values of quail meat. NegCon diet promoted the least cooking losses (16.51%) when compared to PosCon and Ljav25 diets, which significantly did not differ. It was concluded that inclusion of L. javanica in quail diets at 25 g/kg feed promoted similar growth performance, health status, and carcass and meat quality traits as the commercial grower diet containing antibiotics. Lippia javanica leaf meal, therefore, has potential as an alternative to antibiotic growth promoters in Japanese quails.
Keywords: Antibiotics, health, Lippia javanica, physiological response, quails