THE INFLUENCE OF GENOTYPE AND DIETARY SALT LEVELS ON THE FAECAL CHARACTERISTICS OF ISA BROWN AND HARCO BLACK LAYERS

Abstract

This experiment was performed to unravel the effects of genotype and dietary salt levels on the faecal parameters of two breeds of laying birds. Four experimental diets designated as: T1 (control diet with 0.25% salt), T2 (0.50% salt), T3 (0.75% salt) and T4 (1. 00% salts) were fed to Isa Brown and Harco Black breeds of birds. The birds were fed with these diets for a period of twenty weeks. Faecal samples were collected and analyzed for total faecal output, faecal dry matter, faecal volume, faecal density, faecal consistency and faecal moisture content during the last week of the experiment to ascertain the effect of varying dietary salt on the faecal parameters of the birds. The result showed that faecal volume and faecal density were significantly different (P < 0.05) between breeds and among the different dietary treatments. The Harco Black breed had a higher faecal volume (34.88+0.85ml) than the Isa Brown breed (33.25+0.49ml) while faecal density was lower in Harco Black (1.44+0.03g/ml) than in the Isa Brown breed (1.51+0.02g/ml). The highest faecal volume (35,75+1.44ml) and lowest faecal density (1.410.05ml) were recorded in birds fed I. 00% dietary salt. Percentage faecal moisture, faecal dry matter and faecal consistency were statistically similar between breeds but total faecal output was significantly different between Harco Black (1386.38+52.85g) and Isa Brown (1485.00+54.62g) breeds. The diet with 1.00% salt was consistently higher in total faecal output (1562.75+30.45g) and percentage faecal moisture (75.50+3.43) and lower in faecal dry matter (24,50+3.43%) and faecal consistence (1 _50+0.29) than in all the other three diets. The best combination of breed and salt level that would ensure maximum management and physiological benefits to the birds in terms of faecal volume, consistency, density and output could be achieved at 0.75% salt level for both the Isa Brown and Harco Black laying chickens. It could be concluded within the limit of this study that the Isa Brown breed had a higher faecal output than the Harco black breed. Also for litter management and physiological considerations, these two breeds of laying chickens could be fed diets with maximum inclusion of 0.75% dietary salt.